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1. Field of the Invention
The invention relates generally to percussion bits. More specifically, the invention relates to a bit retention system that, in the event of bit breakage, retains the head of the bit for easier removal from the drilled hole.
2. Background Art
Percussion bit systems are often used in drilling or boring through the earth's surface. In a percussion bit system, a percussion hammer is used to drive the percussion bit into the ground using the reciprocating action of a piston to energize the bit.
FIG. 1 illustrates a conventional percussion bit assembly design 100 that does not include a bit retainer. The percussion bit assembly 100 comprises a hammer case 101 that connects to a lower end of a drill string (not shown) through a threaded pin connection 145. The lower end of the hammer case 101 is threadedly engaged with driver sub 102. A plurality of splines (not shown) disposed on the driver sub 102, engage a plurality of splines 115 disposed on the shank 112 of the hammer bit 110, and rotatatively drive the bit 110. The upper end of the hammer bit 110 includes a piston strike surface 148 and a foot valve, or blow tube, 147. The lower end of the hammer bit includes a head 111.
The hammer assembly includes a control tube 143 and an annular piston chamber 146. Pressurized air moves a piston 142 in a reciprocating motion inside the annular piston chamber 146. A check valve 144 is used to communicate between the control tube 143 and the drill string (not shown). The lower end of the piston 142 is adapted to strike the piston strike surface 148, thereby imparting kinetic energy to the bit 110.
Occasionally, the bit 110 may fail and crack across the shank 112 of the bit 110 during drilling. If this happens, the head 111 of the bit 110 is left in the hole and has to be retrieved later through a costly fishing operation. In fact, most conventional hammer bits comprise a fishing thread 140 formed into the head 111 of the bit 110 to facilitate retrieving a broken head 111 from a drilled hole.
A bit retainer 205, as shown in FIG. 2 can be used to retain the head 211 of a bit 210 to the hammer assembly. FIG. 2 shows a conventional bit retainer system 200 comprising a driver sub 202, a bit retainer 205, and a bit 210. U.S. Pat. No. 5,065,827 assigned to the assignee of the current invention, is an example of such a conventional bit retainer.
The driver sub 202 comprises a first outside diameter 233 and a second outside diameter 232, wherein the second outside diameter 232 is larger than the first outside diameter 233. An external shoulder 230 is formed by the two sections. The driver sub 202 is disposed around shank 212 of bit 210. A plurality of splines (not shown) on the inside diameter of the driver sub 202 engage a plurality of splines 215 on the outside diameter of the shank 212 and rotatively drive the bit 210.
A bit retainer 205 is disposed around the driver sub 202 and the bit 210. An internal shoulder 208 engages the bit retainer 205 with the driver sub 202. The pin end 203 of the driver sub 202 is threadedly connected with the hammer case 201. An upper shoulder 234 of the bit retainer 205 abuts the hammer case 201. The internal shoulder 208 between the bit retainer 205 and the driver sub 202 supports the axial load generated by tightening the driver sub 202 to the hammer case 201.
The bit retainer 205 further comprises a catch thread 207 on its lower end that, in the event that the bit 210 breaks in the shank 212 area, a retaining thread 213 on the bit 210 engages the catch thread 207. This prevents the head 211 of the bit 210 from separating from the percussion bit assembly.
The internal shoulder 208 provides an axial stop function and also serves as the primary load-carrying and torque-carrying mechanism. The inside diameter of the shoulder 208 must be slightly larger than the first outside diameter 233 of the driver sub 202 to allow the bit retainer 205 to pass over the driver sub 202 during assembly of the two components. The internal shoulder 208 must be large enough to support the axial load generated by the makeup of the system. The bit retainer 205 must have a greater diameter than that of the driver sub external shoulder 230 to allow the catch threads 207 at the lower end of the bit retainer 205 to pass over the shoulder 230 during assembly. The thickness of the bit retainer 205 must also be sufficient to support the axial load sustained when pulling a broken bit head out of the hole. In a conventional bit retainer, these considerations result in a system where the outside diameter of the bit retainer 205 is larger than the outside diameter of the drill string casing 201.
The drill bit 210 generates cuttings that are carried by drilling fluid past the bit retainer 205 and hammer case 201. The velocity of the drilling fluid and cuttings is greater around the bit retainer 205 than around the hammer case 201, because the bit retainer 205 is larger in diameter than the hammer case 201. This results in less flow area between the bit retainer 205 and the hole wall. The cuttings are abrasive and cause erosion of the bit retainer 205, limiting its useful life. Further, in sticky formations, the bit retainer 205 may impede cuttings from being removed from the bit 210 and carried further up the hole due to its larger diameter. It is therefore desirable to construct a system wherein the outside diameter of the bit retainer 205 is substantially similar to the outside diameter of the hammer case 201.
Typical dimensions for a conventional hammer and bit retainer are now provided to illustrate exemplary bits. No limitation on the scope of the invention is intended by any reference to any specific dimension. The major diameter 235 of the threaded pin end 203 of the driver sub 202 is approximately 6.250 in. for a 8¾ in. for a conventional hammer and bit retainer used in an 8¾ in. hole size. The bit retainer 205 must pass over this diameter as a clearance fit, so the designed inside diameter is approximately 6.310 in. It is customary to bevel sharp corners to prevent handling damage to parts and personnel, so a 45 degree by 0.070 in. chamfer is used. This brings the inside diameter of the shoulder 208 to 6.450 in. The mating shoulder 230 on the driver sub 202 is limited by the driver sub outside diameter 232, which is about 6.800 in. The shoulder 230 also has a 45 degree by 0.070 in. chamfer, so the actual driver sub shoulder 230 outside diameter is 6.660 in. The bit retainer shoulder 208 inside diameter and the driver sub shoulder 230 outside diameter define the contact area, which is 2.162 square inches. The yield strength of the bit retainer 205 is specified as 125,000 psi, and a commonly used design criteria for shoulder loading is 66% of yield strength. Therefore, the shoulder 208 is capable of sustaining about 178,365 lb. of load. Based on this load, and a thread lubricant friction coefficient of 0.080, the connection is limited to a makeup torque of about 11,000 ft.-lb. of torque. This value is about half that of the nearby connections in the hammer, and less that half the makeup torque of the connections in the drill string. As a result, the shoulder 208 is likely to crush when high torque is encountered during drilling.
The bit retainer 205 must pass over the driver sub outside diameter 232, so its minor diameter is 6.820 in. The channel 209 in the bit retainer inside diameter must be large enough to allow the bit retaining thread 213 to move freely in the channel 209 without contact. The major diameter 236 of the retaining thread 213 on the bit 210 is 6.984 in., so the channel inside diameter 237 is 7.00 in. The typical bit retainer outside diameter 238 is 7.625 in., which leaves a 5/16 in. wall thickness of the bit retainer 205 in the area of the channel 209.
The clearance between the bit retainer outside diameter and the wall of the 8¾ in. drilled hole is 0.562 in. per side, resulting in about 14.5 square inches of annular flow area. In deep hole drilling with this hole size, between 2400 and 4000 standard cubic feet per minute (SCFM) of fluid flow is typically used to operate the hammer and remove cuttings from the hole. Depending on the air flow rate and the abrasivity of the drilled cuttings, the life of a bit retainer may be limited to roughly fifty to two hundred operating hours due to the erosive action of the cuttings on the bit retainer. The outside diameter of the mating hammer case is 7.150 in., resulting in a hole wall clearance of 0.800 in. and an annular flow area of about 20 square inches. The air velocity past the hammer case is about 27% lower than air velocity past the bit retainer. As a result, hammer cases erode much less than bit retainers and have a longer useful life. It is, therefore, desirable to reduce the outside diameter of the bit retainer to thereby reduce air velocity and erosion. However, in reducing the outside diameter of a conventional bit retainer, either wall thickness or shoulder diameter must also be reduced. This reduction in either wall thickness or shoulder diameter reduces the strength and torque capability of the bit retainer. | {
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This invention generally relates to non-impact printing and, in particular, to high speed printing using a plurality of electrically controlled liquid ink jets.
In an ink jet printer, the print head structure may be a multiple nozzle type, with the nozzles aligned in a vertical line and supported on a print head carriage which is caused to be moved or driven in a horizontal direction for printing in a line manner. The ink droplet drive elements or transducers may be positioned in a circular configuration with ink passageways leading to the nozzles. Alternatively, the printer head structure may include a plurality of equally spaced horizontally aligned single nozzle print heads which are caused to be moved back and forth horizontally to print successive lines of dots making up the lines of characters. In this latter arrangement, the drive elements or transducers are individually supported along a line of printing.
There are a number of ways to generate an ink droplet. This invention is concerned with piezoelectric transducers as the drive elements. Heretofore, most such devices have been manufactured as single jets and then assembled into arrays. The single jets are operated to eject droplets on demand in contrast to creating droplets from a continuous jet where the piezoelectric device simply is used as a modulating drive means. Such continuous ink jet systems require special apparatus for deflecting the droplets and collecting the ink that is not destined for the printing medium. This invention is not concerned with continous ink jet systems.
The resolution of the printing system is generally measured in "dots per inch". In ink jet systems, a high resolution requires close spacing of the jets. Manufacturing single jet devices assembled into arrays is costly, particularly for heads containing a large number of jets. While print heads comprising arrays of single jets have been manufactured using standard piezoelectric crystals, they suffer from several disadvantages. Specifically, since piezoelectric crystals are brittle and must themselves be grown from crystals, they require careful handling in production. More importantly, these characteristics limit the minimum thickness and maximum size of the crystals. Another major factor in using piezoelectric crystals is that their dielectric breakdown limits the voltage that can safely be applied. As a result of these physical properties, the number of jets that can be assembled or placed in a given area is limited. Present constructions would require the stacking of several head assemblies.
Examples of prior ink jet print heads using piezoelectric crystals or like transducers are shown in U.S. Pat. Nos. 4,415,909 to Italiano et al, dated Nov. 15, 1983; 4,418,354 to Perduijn, dated Nov. 29, 1983 and 4,418,356 to Reece, dated Nov. 29, 1983.
Another form of ink printing device using a piezoelectric drive element is shown in U.S. Pat. No. 4,379,246 to Guntersdorfer, dated Apr. 5, 1983, wherein a piezoelectric drive element surrounds an ink channel of a writing jet in a mosaic printing device. The drive element is a winding formed by plies of thin synthetic foil having piezoelectric properties. In this apparatus, the foil is cut into individual pieces. U.S. Pat. No. 4,282,532 to Markham, dated Aug. 4, 1981, shows an ink jet apparatus using a thin film piezoelectric exciter for drop generation. However, the piezoelectric film is used in a continuous jet apparatus for modulation purposes.
It would be quite advantageous if multiple individual jets could be built on a common substrate with very close spacing, to yield a high dot per inch resolution capability not heretofore available. This invention is directed to satisfying this and other needs and solving problems with prior ink jet printing heads or the like. | {
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1. Field of the Invention
This invention relates to the field of chemical, biological agent and radiation sensors, and in particular, to such sensors embodied in surface acoustic wave devices.
2. Description of Related Art
Surface acoustic wave (SAW) devices are electronic components, embodied as filters, resonators, and delay lines exploiting surface acoustic waves in piezoelectric crystals. An interdigital transducer (IDT) converts an electronic signal into a surface acoustic wave which, propagating 100,000 times slower than electromagnetic waves, can deliver significant signal delays in the device. Signal filtering is performed by apodized IDT during electric to SAW signal conversion, or back conversion by another IDT. This is referred to as transversal filtering.
SAW devices can be used to detect intrinsic properties, and as such, are used as chemical, biological agent and radiation sensors and analyzers. As noted, a basic SAW device is a quartz crystal designed to support high-frequency acoustic oscillations. These oscillations are quite sensitive to surface effects. If the surface of a SAW device is provided with a coating which is attractive to a desired chemical or class of chemicals, for example, then such chemicals will tend to be adsorbed by the coating when in the presence of the SAW device. The difference between the fundamental frequency of the coated SAW device prior to adsorption of chemicals and after the adsorption of chemicals can be a reliable and accurate measure of the presence or concentration of the adsorbed chemical, although not both simultaneously. SAW devices with coatings which exhibit a preference for absorbing particular kinds of radiation, for example photo-conductivity or heating under the effects of ultra violet or infrared light, can be used as detectors for such radiation. The difference between the fundamental frequency before and after exposure to the radiation can produce a measurable shift in the fundamental frequency of the coated SAW device which can be a reliable and accurate measure of the presence or concentration of radiation, although not both simultaneously. SAW devices with coatings which adsorb and desorb (that is, release) chemicals or thermal energy, for example, as concentrations of the chemical or thermal energy rise and fall, can be used as continuous detectors.
Development of new chemical, biological agent and radiation sensors, and/or new methods of improving the sensitivity and detection limit of existing systems, are important areas of current research. The conventional method of measuring gas concentration using a SAW sensor is by measuring changes in only the fundamental frequency. For practical considerations, the majority of SAW gas sensors operate at frequencies below 300 MHz. The sensitivity of SAW devices is a function of the square of the operating frequency. Thus, although potentially more sensitive than other gas sensing methods, such as the use of infrared absorption spectra, these practical limitations restrict their actual sensitivity to many gases. In addition, the identification of a particular species from interfering gases by measuring a single parameter, that is frequency, is impossible. Attempts to solve this problem have conventionally been using an array of several sensors. However, in many cases false identification remains a problem.
Most publications and patents on SAW chemical sensors relate to the development of new polymer or conductive coatings for sensing particular gases of interest, or the use of sensor arrays to detect a particular gas of interest among interfering gases. However, their sensitivity relative to other methods such as those described above remains poor. U.S. Pat. No. 5,076,094 describes a method for identifying and quantifying absorbed chemical species by measuring changes in both the velocity and attenuation of the acoustic wave traveling through a thin film into which the chemical species is absorbed. | {
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U.S. Pat. 4,509,335 to Griffin et al has a valve controlling the amount of cooled air flowing from an evaporator into a fresh food compartment for controlling the ratio of air flow to the fresh food compartment and a freezer compartment. The valve is disposed at an outlet of a duct through which air flows from a fan after passing over the evaporator to the fresh food compartment and is manually adjustable by a user.
It has been found that the user cannot always satisfactorily obtain a desired position of the valve. Thus, it is desired to prevent a user from adjusting the valve while still having the capability of adjusting the ratio of the cooled air from the evaporator to the freezer and fresh food compartments. | {
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An example of a card connector of such a type can be found in Japanese Utility Model Publication No. 92-86970 and Japanese Utility Model Publication No. 93-75974. Both card connectors described in these publications have a cam member mounted in a rotational manner in the housing accommodating the card and a sliding lever linked to the cam member. In these card connectors, the cam members can be rotated by pushing the lever in an assigned direction, thus causing the ejection of the card inserted in the connector. In the second card connector, a spring is provided which at all times applies spring force to the lever in the direction opposite to the direction the lever is pushed to eject the card.
However, the above card connectors needed improvements because they had relatively complicated structure and were difficult to assemble. Therefore, the purpose of the present invention is to offer a card connector having less complicated structure and an easier assembly process. | {
"pile_set_name": "USPTO Backgrounds"
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This invention relates generally to an automated process and apparatus for the solvent separation of organic/inorganic substances. More particularly, the invention relates to an automated process and apparatus for the solvent extraction of molecular constituents of coal-derived material such as coal liquefaction process streams.
In processes such as the SRC-I process for the solvent refining of coal there is a need for the separation and characterization of coal-derived oils. While many procedures have been used over the past forty years to monitor coal conversion products, no standard procedure has evolved that is widely used to separate and characterize liquefied or solvent refined coal products. The problems with the prior procedures are that they lack reproducibility, give low or high material balance, are time consuming, and/or involve frequent subjective judgments.
The state of the prior art is described in the following prior art materials, which pertains to manual procedures, whereas the process and apparatus of this invention are automated.
ANALYTICAL CHEMISTRY, Volume 50, No. 9, August, 1978, page 1381+, Article Entitled "Solvent Extraction of Coal-Derived Products",
WILSONVILLE, ALA. ANALYTICAL PROCEDURES 34550-3, "Determination of Product Distribution by Soxhlet Extraction" and 34550-17, "Benzene Insolubles in Filtrate."
FUEL, Volume 58, July, 1979, pages 539-541, Article by Burke et al. Entitled "Liquid Column Fractionation; A Method of Solvent Fractionation of Coal Liquefaction and Petroleum Products." | {
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High moment materials are used in various layers in electronic devices. For example, magnetic recording head structures, such as write transducer poles and shields, may include conventional multilayers. The conventional layers in the multilayers may be formed by some combination of sputtering and/or plating. At least some of these layers may include high Bsat materials, such as high-Fe content alloys. Such materials often have a galvanic potential that is highly polarized in the negative direction and are thus subject to corrosion. These alloys may also be in contact with more noble materials. For example, a higher-Fe content Fe alloy having a more negative galvanic potential may be in contact with a lower-Fe content alloy having a less negative galvanic potential. Because of the galvanic coupling between these materials, the higher-Fe content alloy may be particularly susceptible to corrosion.
Various conventional mechanisms exist for reducing corrosion of such high moment layers in a device. For plating processes time limitations are typically set for loading and unloading/time before rinse of a substrate to limit exposure of the material to an environment in which the material(s) may corrode. However, corrosion may still occur. If the material is plated, conventional “hot loading” and “hot unloading” may be used. In conventional hot loading/unloading, a protective cathodic current passes through the deposition substrate as the substrate is loaded into/unloaded from the plating cell. However, this conventional method is only effective as long as the cathodic current is passing through the device. Further, this conventional method may be less effective during the unloading. Once removal of the substrate from the plating cell causes the circuit to break, protection due to the cathodic current is lost. Exposure to corrosion then intrinsically exists because the unprotected substrate remains in contact with acidic plating solution until rinse. The risk of corrosion is higher for plating operations where plating-to-rinse transfer times are greater. However, this risk can still be significant for lower transfer times achievable in automated plating tools. Consequently, materials in a device such as a magnetic recording transducer are subject to corrosion.
Accordingly, what is needed is a system and method for providing a transducer that may mitigate corrosion of high moment layers. | {
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The present invention relates to time-of-flight ranging or pulse-echo ranging systems, and more particularly to a method and apparatus for calibrating operation of the pulse-echo ranging system for level measurement applications.
Pulse-echo acoustic ranging systems, also known as time-of-flight ranging systems, are commonly used in level measurement applications. Pulse-echo acoustic ranging systems determine the distance to a reflector (i.e. reflective surface) by measuring how long after transmission of a burst of energy pulses the echo or reflected pulses are received. Such systems typically use ultrasonic pulses or pulse radar signals.
Pulse-echo acoustic ranging systems generally include a transducer and a signal processor. The transducer serves the dual role of transmitting and receiving the energy pulses. The signal processor is for detecting and calculating the distance or range of the object based on the transmit times of the transmitted and reflected energy pulses.
Since the transmitted energy pulses are converted into distance measurements, any timing errors arising in the circuitry of the device result in distance measurement errors which degrade the accuracy of the level measurements. In most cases, timing errors are a result of temperature drift and drift over time in the operating characteristics of the electronics in the device circuitry. Accordingly, it is necessary to calibrate time-of-flight ranging systems not only at installation, but on a periodic basis as well in order to insure accurate level measurements.
While there is a need to periodically calibrate, the time-of-flight ranging systems are not always easily accessible after installation. In addition, there is a cost involved with a technician conducting calibration tests on an ongoing basis.
Accordingly, there remains a need to provide a system and techniques which facilitate calibration of pulse-echo or time-of-flight ranging systems while overcoming these and other perceived shortcomings.
The present invention provides a calibration module and calibration techniques for a pulse-echo acoustic ranging or time-of-flight ranging systems.
In a first aspect, the present invention provides a time-of-flight ranging system comprising: (a) a transducer for emitting energy pulses and detecting reflected energy pulses; (b) a controller; (c) a transmitter operatively coupled to the controller, and the transducer having an input port coupled to the transmitter module and being responsive to a transmit pulse signal for emitting the energy pulses; (d) a receiver operatively coupled to the controller, and the transducer including an output coupled to the receiver for outputting a reflected pulse signal corresponding to a reflected energy pulse coupled by the transducer; (e) the receiver converting the reflected pulse signal for input by the controller and the controller including a component for determining time-of-flight measurements from the reflected pulse signal; (f) a calibration module having a loop-back component for bypassing the transducer and routing the transmit pulse signal to the receiver, and the controller including a calibration component for processing the output from the receiver.
In another aspect, the present invention provides a method for calibrating a time-of-flight ranging system, the time-of-flight ranging system includes a transducer for emitting energy pulses and detecting reflected energy pulses, a transmitter operatively coupled to a controller and the transducer being responsive to a transmit pulse signal for emitting the energy pulses, a receiver operatively coupled to the controller and having an input for receiving a reflected pulse signal corresponding to a reflected energy pulse from the transducer, the receiver converting the reflected pulse signal for input by the controller and the controller including a component for determining time-of-flight measurements associated with the reflected pulse signal, the calibration method comprises the steps of: (a) bypassing the transducer and looping back the transmit pulse signal to the receiver; (b) inputting an output signal generated by the receiver corresponding to the looped-back transmit pulse signal; (c) measuring characteristics associated with the output signal; (d) determining calibration parameters from the measured characteristics.
In a further aspect, the present provides a time-of-flight ranging system comprising: (a) emitter means for emitting energy pulses and detecting reflected energy pulses; (b) controller means; (c) transmitter means for transmitting a transmit pulse signal, the transmitter means being operatively coupled to the controller, and the emitter means having an input port coupled to the transmitter means and the emitter means being responsive to a transmit pulse signal for emitting the energy pulses; (d) receiver means for receiving a reflected pulse signal, the receiver means being operatively coupled to the controller means, and the emitter means including output means coupled to the receiver for outputting the reflected pulse signal corresponding to a reflected energy pulse coupled by the emitter means; (e) the receiver means including means for converting the reflected pulse signal for input by the controller means and the controller means including means for determining time-of-flight measurements from the reflected pulse signal; (f) means for bypassing the emitter means and routing the transmit pulse signal to the receiver means, and the controller means including calibration means for calibrating the output from the receiver.
Other aspects and features of the present invention will become apparent to those ordinarily skilled in the art upon review of the following description of specific embodiments of the invention in conjunction with the accompanying figures. | {
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1. Field of the Invention
The present invention relates to a particle sensor for detecting the solid particles contained in a fluid.
2. Description of Related Art
When solid particles are present in a fluid (a liquid or a gas), it is necessary in some cases to detect presence of those the solid particles. Detection of such solid particles is particularly important when the solid particles present in the fluid detrimentally affect the intended action of the fluid.
Lubricating oils (e.g. engine oils) are used in internal combustion engines of automobiles or heavy machinery in order to reduce the frictional resistance and abrasion of the rotating surfaces and sliding surfaces of the engines. Operation of such internal combustion engines generates solid particles (e.g. metal fine particles) caused by abrasion, and the solid particles are taken into the lubricating oils and accelerate the abrasion of the rotating surfaces and sliding surfaces. The solid particles, etc. present in the lubricating oils are ordinarily removed by the use of a filter, such as oil filter or the like. The condition of the lubricating oils can be monitored by detecting the solid particles present in the lubricating oils.
Hydraulic oils and flushing oils are used in power transmission mechanisms (e.g. transmission), oil hydraulic pipe systems (e.g. oil hydraulic servo valve), rolling, pressing, etc. It is important to control the condition of these oils by detecting the solid particles present in the oils and/or examining the viscosities of the oils.
It is also important to detect the particles suspended in the air or examine their concentration in the air in order to monitor the level of air pollution. Such detection includes detection of the particles suspended in the exhaust gas discharged from a plant, a factory or the like.
For such detection of solid particles present in a fluid, a particles sensor comprising a sensor element using a piezoelectric film is disclosed in Japanese Patent Application Laid-Open (Kokai) No. 7-301594. With this particle sensor, solid particles present in a fluid collide with the detecting section (having a piezoelectric film) of the sensor element or with the vibrating section (mounting the detecting section thereon) of the sensor element, thereby causing the vibrating section and the detecting section to vibrate. The piezoelectric film converts the vibration into electric signals, which are outputted by electrodes holding the piezoelectric film between them.
In detecting solid particles contained in a fluid by the use of a particle sensor such as mentioned above, the vibrating section of the sensor element of the particle sensor is vibrated not only when the solid particles in a fluid collide with the vibrating section but also when the flow of the fluid becomes turbulent as a result, electric signals are outputted from the detecting section of the sensor element. Moreover, electric noise signals may enter the particle sensor from outside.
No method has heretofore been established to clearly distinguish the above-mentioned three kinds of electric signals, i.e. (1) the electric signals caused by the collision of solid particles (the signals are hereinafter referred to as "particle signals"), (2) the electric signals caused by the turbulent flow of fluid (the signals are hereinafter referred to as "turbulent flow signals") and (3) the electric noise signals which may enter the particle sensor from outside (the signals are hereinafter referred to as "electric noise signals"). This is one reason that the detection of solid particles in fluid has been unreliable. | {
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Systems for generating electrical energy are seeing changes as a consequence of considerations relating to environmental policy. The classic energy supply mains with few large central power stations can be in the course of time superseded by a modern power supply mains with which numerous smaller energy suppliers are decentrally connected. The tasks to be solved by the operator of the modern power supply mains are as a result far more complex. The supply of renewable energy by energy suppliers, who utilize wind and solar energy, is in some cases plannable only to a limited extent and is subject to substantial fluctuations. In the immediate future a compound operation therefore may prevail in which compensation for failures of energy supplies of alternative energy suppliers is provided by energy supplies from conventional power stations.
In order to keep the supply of electrical energy delivered by the power stations in balance with the need for electrical energy and to help ensure stability and reliability of the power supply mains the energy suppliers and electricity users connected therewith can be continuously monitored. For that purpose the course of load of the power supply mains can be also monitored so as to determine time zones with higher loading. Based on the determined course of load, static electrical loads are switched off at critical time periods so that a load balance can be achieved over longer periods of time.
The connection and disconnection of loads is traditionally carried out by ripple control. In modern power supply mains, i.e. so-termed ‘smart grids’, ripple control is supplemented by ‘smart meters’, which allow detection of the state of the power supply mains close in time to numerous mains junctions. The communication of the decentral measuring units or ‘smart meters’ with a central station is possibly carried out by way of a network operating according to Internet protocols. A method for short-cyclic data detection and control of measuring points in an intelligent power supply mains, which uses smart metering or smart grid functions, is known, from, for example, WO 2012/055566 A2.
If a difference between the supply of and requirement for energy now arises, the regulating energy or regulating power made available by the energy suppliers is used in order to avoid collapse of the power supply mains in the case of increased need or an energy excess in the case of too-small demand. Compensation for the mentioned differences or fluctuations in the power supply mains is provided by means of the regulating energy.
The available regulating energy is divided into different categories. Regulating energy able to be called up within seconds is termed primary reserve. Regulating energy able to be called up within a minute is termed secondary reserve. Moreover, the regulating energy comprises reserve components which can be called up after quarter of an hour (minute reserve) or after hours (hour reserve).
In the case of overloading of the power supply mains, positive regulating energy or current is stored in the power supply mains. If there is an energy excess, negative regulating energy is taken from the power supply mains. Use of power stations capable of regulation is made for the required adaptations of output, such as rapid-response gas-turbine power stations or pumped-storage power stations. It can be disadvantageous even with fast-start power stations that supply always takes place with a significant delay. A primary reserve, which can be used virtually without delay, is hardly ever available. Moreover, energy from the primary reserve can be expensive.
The regulation of the power supply mains can be even more demanding by energy consumers, such as elevator installations, which draw larger amounts of energy from or feed such back to the power supply mains. Whereas connection or disconnection of apparatus with low energy consumption is usually uniformly distributed due to the high number or is plannable on the basis of experience this is not the case with elevator installations. Dynamic loads, such as elevator installations, can relatively strongly load the power supply mains selectively at any time of day or time of night. To the extent that, for example, a larger travel group enters different hotels at night time when the mains operator does not expect greater loads, several elevator installations can coincidentally be simultaneously actuated whereby a high loading is abruptly triggered. On the other hand, insofar as an energy excess is present and the elevator installations can feed additional energy back to the power supply mains, this equally should be absorbed by the regulation technology of the power supply mains. It is to be noted that primarily expensive primary reserves may be required to provide compensation for these processes.
The presence of larger energy consumers, such as elevator installations possibly with several individual elevator units, may require a high level of availability of the regulating capacities of the power supply mains. In particular, possibly expensive primary reserves may be provided. | {
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1. Field of the Invention
This invention relates to sporting sticks and more particularly relates to sporting sticks configured to impact a sporting implement.
2. Description of the Related Art
Hockey is a fast moving, competitive game. Hockey players use hockey sticks to control the puck or ball during the game. Players also use the sticks to shoot the puck during the game, as well as to knock the puck away from opposing players.
Hockey sticks generally include a handle portion and a blade portion. The handle portion is generally elongate and is specially configured to be held by the player during the game of hockey. The blade portion extends from a distal end of the handle portion and is shaped to allow a player to control and shoot the hockey puck with the blade.
In some embodiments, the hockey stick blade comprises a foam core that is surrounded by a hard outer layer. Often, the outer layer includes a composite material such as fiberglass or carbon fiber.
While playing hockey, a player often controls and shoots the puck with the blade. One particular type of shot is a “slap shot,” which is an extreme shot in which a player hits the puck with great force. A slap shot is the fastest of all hockey shots. Dury a slap shot, a player makes a sweeping motion with an accentuated backswing to shoot the puck. Another category of extreme shot is the “one-timer,” in which a player shoots a puck (usually from a teammate's pass) without taking the time to stop and control the puck. Usually, a one-timer is in the form of a slap shot. Slap shots and other one-timers typically impart high energy and speed into the puck, and thus the impact between the puck and the blade during one-timers can result in high forces in a “strike zone” of the blade where the puck and blade meet. During this contact, the composite outer layer of the blade may deform somewhat. However, the outer layer is supported by the foam core, and thus the impact force and corresponding deformation is distributed. In a typical foam-core hockey stick blade, the foam tends to breakdown after repeated impacts due to slap shots and other extreme shots. Such foam breakdown creates a void behind the composite layer in the strike zone. Because of this void, the composite layer is no longer supported by foam. Depending on the amount of force and repetition of extreme shots, the unsupported composite layer will break down and the blade will fail. Such blade failure is especially prevalent in very light, high performance hockey sticks. | {
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The present invention relates to an apparatus for mixing both liquid and gaseous substances, such as chemicals, into a medium formed of solid and liquid substance, especially to fiber suspensions being generated during processing of wood or other vegetable-originating substance. To this kind of suspensions typically belong the fiber suspensions of the pulp and paper industry, such as chemical pulp and mechanical pulp suspensions, as well as pulp suspensions of paper production.
For mixing chemicals and gases into fiber suspensions, dynamic mixers are used, which typically are provided with a rotating rotor for effecting the mixing, and static mixers. In the latter, some sort of throttling has been arranged in the flow channel, where the flow rate is increased and the static pressure is decreased. Chemical is introduced into a lower static pressure zone or it can be introduced upstream of the point of throttling. In a static mixer, by throttling the flow, i.e. decreasing the cross-sectional area, an increase in the flow rate is achieved and due to the throttling and the shape of the flow channel a higher turbulence is generated, whereby the introduced chemical will mix into the actual flowing medium. Static mixers are typically provided with, in addition to or alternatively to the throttling, flow barriers arranged in the flow channel for generating turbulence.
Fiber suspension is a demanding material flow in view of mixing, because in order to obtain a good mixing result the fiber network (fiber flocks) are to be decomposed. In the mixing, the turbulence is to be at a level that decomposes the fiber flocks into microflocks and individual fibers, whereby the bleaching chemical is made to be distributed in the vicinity of the individual fibers. Traditionally, with medium consistency fiber suspensions high-capacity fluidizing chemical mixers have been used, wherein the rotor of the mixers generates the turbulence required for the mixing. Although modern fluidizing chemical mixers are reasonably small, intensifying energy consumption creates needs to decrease the amount of energy used for mixing chemicals.
The operation of static mixers is based on utilizing the pressure loss taking place in the apparatus and/or dividing the suspension flow into partial flows and combining them in the flow direction so that the concentration differences upstream of the mixer will be equalized.
European patent 1469937 (WO 03/064018) describes an apparatus for admixing a gas or a liquid into a material flow. In this apparatus a tube with a circular cross section is provided with a chamber for the material flow. The chamber has an inlet part, the cross section of which later changes from circular to oval while the area remains unchanged and an outlet part, the cross section of which later changes from oval to circular while the area remains unchanged. Gas or liquid is fed into the material flow at the narrowest point of the apparatus, which is provided with e.g. small circular holes around the chamber. The change of the material flow from laminar to turbulent state takes place when the minimum height of the oval cross section is defined in a proper way. The gas or the liquid is added in the turbulent zone.
For adding steam into a fiber suspension, direct heat injection heaters are used. In those the steam is admixed directly into a flowing fiber suspension to be heated, whereby the heating takes place quickly. Although direct steam injection heaters are efficient, fiber suspensions with flocking matter tend to clog the heater, if the suspension is to flow through bends and turns. U.S. Pat. No. 6,361,025 describes a direct steam injection heater that is designed for viscose material flows, such as fiber suspension, and in which the steam is introduced into the suspension flowing axially through a tube. In the construction according to U.S. Pat. No. 6,361,025 steam feed takes place in a cylindrical perforated part mounted through the device. The number of open holes can be regulated by means of a cover located inside the cylindrical tube, by means of which the steam feed can be totally closed if needed and also the passing of pulp to the interior of the cover or further into the steam feed piping can be prevented. The perforated cylindrical pipe, referred to as a Mach-diffuser, is mounted transversely with respect to the axial flow of the suspension, whereby it divides the flow space into two parts. Small jets of steam are easily scattered in a viscose suspension and distributed before the steam has a possibility to combine into large bubbles which may generate pressure shocks as steam is suddenly condensed. The smaller the bubbles of the condensing steam, the smaller is the pressure shock caused for the piping. Condensing of a large steam bubble on the inner surface of the pipe causes a strong pressure shock and noise and strong mechanical vibration in the piping. The cover is preferably rotatable with respect to the longitudinal axis of the Mach-diffuser mounted transversely with respect to the flow of the suspension. When the cover is rotated open, holes are freed both from the upper and the lower side, wherethrough the steam flows into the by-passing pulp.
The direct steam injection heat exchanger of the above-mentioned US-patent is advantageous as a steam feeding device, because the steam is fed via several small holes into the by-flowing pulp. As long as the pressure drop across the small open steam holes is adequate, the flow of the steam into the suspension remains even. When the velocity of the steam is adequately high, even condensing of the steam is obtained due to high turbulence caused by the steam feed. The steam condenses evenly, as the condensing takes place near the feed point.
When the pressure loss generated in a static mixer is utilized for effecting the mixing, the mixing result often varies depending on the pressure loss. If a static mixer is based on dividing and combining partial flows, the mixing result is not proportional to the generated pressure loss. A possible problem in this type of devices may be clogging of the partial flow channels and clear deterioration of the mixing efficiency, in addition to an increased pressure loss.
Based on the above, when treating fiber suspensions, the static mixer should break the fiber network, preferably fluidize the through-flowing suspension to an adequate extent, and the mixing result should not be dependent on the generated pressure loss, and partial clogging of the device should not affect the mixing result. In the designing of a device for mixing fiber suspension attention is to be paid to the possibility of ensuring the functioning condition of the device even if the suspension has been thickened e.g. due a disturbance situation at the mill. This means that when the mixer is taken into use it will reach an adequate operational level at the same time as the chemical feed is initiated. If a pressure loss generated in the device is utilized for generating turbulence in static mixers, but it is still desired to limit the extent of the pressure loss, the chemical feed is to be as even as possible with respect to the flow cross-sectional area.
In addition to steam or other gas, it is necessary to introduce into the fiber suspension flow also one or more liquid chemicals, such as bleaching chemical, which has to be distributed and mixed efficiently into the fiber suspension in order to ensure adequately quick and efficient reactions between the suspension and the chemical. For instance the above described apparatus presented in U.S. Pat. No. 6,361,025 and manufactured by Hydro-Thermal Co. has been found an advantageous steam feeding apparatus. However, the mixing capability of static mixers to e.g. mix bleaching chemicals into a fiber suspension should be improved. | {
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1. Field of the Invention
The present application is related generally to a data processing system and in particular to a method and apparatus for a domain name server. More particularly, the present application is directed to a computer implemented method, apparatus, system, and computer usable program code for updating a domain name server (DNS) to return IP addresses for server interfaces that are reachable.
2. Description of the Related Art
Every computer on the Internet has a unique identifying number called an Internet Protocol (IP) address. An IP address is generally expressed as a decimal number, such as 216.27.62.139. Thus, every computer on the Internet can be identified and contacted using the unique IP address for the computer. However, it would be very difficult for human users to remember an IP address for every web site that a user wants to access. Therefore, humans use domain names.
A domain name is a human-readable host name to stand in for an IP address identifying a particular machine on the Internet. In other words, a domain name is an alphanumeric representation of a particular IP address. For example, “IBM.com” and “wikipedia.org” are domain names. The domain name “IBM.com” is easier for a human to remember than an IP address for one of the servers for International Business Machines, Inc. Moreover, an IP address for a particular machine might change quite frequently, while the domain name generally remains the same regardless of changes in the IP address.
A domain name server (DNS) is an Internet service that translates human readable domain names into IP addresses. When a client wants to access a web page on a server, the client contacts a domain name server to request an IP address corresponding to a given domain name. The domain name server generally responds by providing the IP address for the domain name or providing an IP address for another domain name server that might know the correct IP address.
The domain name server makes it possible to attach easy-to-remember domain names, such as “IBM.com” and “wikipedia.org”, to hard-to-remember IP addresses, (such as 207.142.131.206). Moreover, in any given Internet session, a user will typically require domain name server services dozens or even hundreds of times to obtain needed IP addresses. These domain name server queries take place transparently in client applications such as web browsers, mail clients, and other Internet applications.
A content server is a server providing content or services to a user. To access a content server, a client needs an IP address to access a network interface on the content server. A network interface is any hardware and/or software components providing a point of interconnection between a user or client terminal and another computer on a network, such as the Internet. Content servers are often multi-homed to improve reliability and availability of the content and services provided by the content server. A multi-homed server is a server that has multiple network interfaces, each with a different IP address associated with the interface. When a client wishes to access the content server using the content server's domain name, the domain name server is queried. This query is called a lookup. The domain name server then provides all the IP addresses for the content server to the client.
Typically, the client uses the first IP address that is provided by the domain name server to access the content server. The client expects that the first IP address is a reachable IP address. If the client cannot connect with the content server using the first IP address, the client does not attempt to connect using any other IP address for the content server. In other words, the client assumes the IP address provided by the domain name server can be used to reach a functional network interface on the content server. However, if the network interface corresponding to the IP address provided by the domain name server has failed for any reason, the IP address provided by the domain name server will not enable the client to access the content server.
Currently, domain name servers provide IP addresses for a given content server in random order, with the order varying with each lookup, in order to improve the probability that a reachable IP address will be provided to a client. However, this method can still result in the provision of unreachable IP addresses to clients in response to lookup queries. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
The present invention relates to a method of manufacturing heterojunction transistors with self-aligned contacts, and more particularly to a method of manufacturing mesa-type heterojunction bipolar transistors with self-aligned emitter and base metal contacts.
2. Discussion of the Background
A conventional method for manufacturing a vertical heterojunction bipolar transistor (HBT) is shown in FIGS. 1A-1C. In FIG. 1A, a n-type AlGaAs emitter layer 4, a p-type GaAs base layer 3 and a n-type GaAs collector layer 2 are formed on a semi-insulating substrate 1. Typically, all three layers are grown in one step by a method such as organometallic vapor phase epitaxy (OMVPE) or molecular beam epitaxy (MBE). A masking material 5 is deposited on emitter layer 4 and patterned using standard photolithographic techniques. The emitter layer 4 is then etched using masking layer 5 as a mask to provide the structure shown in FIG. 1B. Masking layer 5 is then removed and electrodes 6 and 7 are deposited using standard photolithographic techniques to provide the base and emitter contacts, respectively, as shown in FIG. 1C. The resulting device does not have self-aligned base and emitter contacts, and has a further disadvantage in that the emitter layer must be etched to expose the base layer. This can be a difficult process when very thin base layers (approximately 200 angstroms) are used or if it is desired to avoid the removal of any base material in order to optimize performance.
A second HBT according to the prior art is shown in FIG. 2. In manufacturing this structure, the base layer 3 is patterned after deposition, and then emitter layer 4 is grown by an overgrowth epitaxy technique to provide a planar surface. Regions 10 and 11 are formed by implantation of impurities such as Be, to provide a base contact via base electrode 6. Emitter contact 7 and collector contact 8 complete the structure. This device requires implantation to contact the base region and the base and emitter contacts are not self-aligned.
A prior art process having self-aligned features is disclosed in U.S. Pat. No. 4,731,340 to Chang et al. A photoresist layer is deposited on an AlGaAs layer used to form the emitter region. Apertures are etched through both the photoresist layer and the AlGaAs layer to expose the base region. Base metallization is deposited over the structure to provide self-aligned base metal contacts. The photoresist layer with the metal deposited thereon is subsequently removed to expose the emitter region. The emitter contact metal is defined by another photoresist mask and a subsequent metal deposition provides the emitter metal contact. While the process of '340 provides self-aligned base contacts, two separate photomasking and metal deposition steps are required as well as a complex combination of etching through both the photoresist layer and the AlGaAs layer. Moreover, the base contacts are aligned with the photoresist, and not the emitter layer.
A further method of forming an HBT according to the prior art is disclosed by Plumpton et al in U.S. Pat. No. 4,868,633. In FIGS. 5A and 6A-6C of '633, a pedestal comprised of layers 238, 240, 242 is selectively grown on a n+/n GaAs collector 234/236 on a GaAs substrate 132 masked by WSi:Zn layer 246. The growth of the layer pedestal avoids any deposition or growth on a WSi:Zn mask in one embodiment, or polycrystalline growth or deposition on a silicon dioxide mask in the second embodiment. The layer pedestal includes both base and emitter layers (or base and collector layers in the second embodiment) and does not require any penetration of the emitter layer (either by doping or etching) to contact the base, but the subsequently formed contacts must include photolithographic tolerances and hence be non-self-aligned as shown in FIG. 5A. This structure has a characteristic of self-aligned base metal in that the extrinsic base is WSi:Zn which has a significantly lower resistance than heavily doped GaAs and is thus significantly improved. However, a significant reduction of base-collector capacitance (or emitter-base capacitance in the second embodiment), largely determined by the approximate distance between the outside edges of the base metal 254 in FIG. 5A, which is also a characteristic of self-aligned base metal, is not achieved since this distance is increased by these photolithographic tolerances. This increase in capacitance lowers the performance of the transistor and the large number of process steps increases the complexity and cost. | {
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In order to catch fish, artificial fishing lures must first attract fish. Numerous prior art lures have been developed that have various features to attract fish. One such type of artificial lure is made of a soft and flexible plastic, allowing portions of the lure to wobble or vibrate as the lure is pulled through the water, thereby drawing attention to the lure. The more a lure moves, the more attention is drawn to the lure and, hopefully, the more fish are caught. However, different fish appear to be attracted to different types of movements. Accordingly, what are needed are new designs for fishing lures that allow the lures to move in a variety of different manners as the lures are pulled through the water. | {
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1. Technical Field of the Invention
The present invention relates to an electric motor suitable for various types of brushless motors for use in industries, home appliances and vehicles, and in particular, to an electric motor suitable for driving compressors for vehicles and suitable for use as servomotors for vehicles.
2. Related Art
Recently, electric motors using permanent magnets as magnetic poles tend to suffer from cogging torque due to the enhancement of magnetic performances.
In this regard, a technique of contriving the shape of magnetic poles is put into practice to reduce cogging torque. However, such a technique raises problems of involving a high-precision press technique and producing a lot of scraps.
A patent document JP-A-2011-050216 discloses a technique of reducing cogging torque and torque ripple by using a specific arrangement of the magnetic poles of a rotor with respect to the teeth of a stator. According to this technique, one magnetic pole is composed of two permanent magnets arranged in a V-shape. The two permanent magnets forming one magnetic pole are arranged in a range which is defined by the center lines of the respective second teeth leftward and rightward of the tooth confronting the center of the magnetic pole.
However, the technique disclosed in JP-A-2011-050216 has a main purpose of reducing torque ripple and thus exerts only a low effect of reducing cogging torque. Further, the technique is only applicable to a type of motors in which one magnetic pole is composed of two permanent magnets (V-shaped arrangement). | {
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1. Field of the Invention
The present invention relates to a counter control method in a microcomputer including a plurality of counters.
2. Description of the Prior Art
FIG. 4 is a block diagram illustrating the start/stop operation for counters included in a microcomputer of this type.
A clock signal (count pulse) transmitted on a signal line 1 from a clock generator (not shown) is input to one terminal of the switching means 4 and 5, which respectively control start/stop operations for the counters 2 and 3. Those counters 2 and 3 are adapted respectively to be different, for example, in their set counts and issue respectively onto signal lines 6 and 7, terminal count signals indicative of the ends of their countings up to the respective set counts.
FIG. 5 is a view of the address configuration of a register for illustrating a prior counter control system. This address configuration is based upon the like configuration of a control register described in the technical sheet of the 8/16 bit 1 chip microcomputer MSM66301 issued from Oki Electric Industry Co., Ltd. As the figure shows, the register has 8 bit information stored therein at its address (a). the bit 0 thereamong including switching information 4S allocated thereto for driving the switching means 4 which serves to start/stop the counter 2. In addition, the register has 8 bit information stored therein at its address (b) in the same manner, the bit 0 thereamong including switching information 5S for driving the switching means 5 which serves to start/stop the counter 3.
In succession, operation of this prior example will be described. The switching means 4 and 5 are closed once the switching information 4S and 5S of a logic level "1" are written in the register at the bits 0 of the respective addresses (a) and (b), for thereby starting the countings by the counters 2 and 3. They are opened once the switching information 4S and 5S of a logic level "0" is written in the register at the bits 0, for thereby stopping the countings by the counters 2 and 3. A central processing unit (operation control means) is assumed here to have a data bit length of 8 bits which are accessible all at one time.
When the central processing unit is needs to start both the counters 2 and 3, for example, using software, it writes data "xxxxxxxl" in the register at the address (a) of FIG. 5. As a result, the switching means 4 of FIG. 4 is closed to thereby start the counting by the counter 2. In succession, the central processing unit writes data "xxxxxxx1" in the same manner at the address (b). Thereupon, the switching means 5 is closed to thereby start the counting by the counter 3. The central processing unit is adapted in such a manner to twice write the data in the register at the addresses (a) and (b) for starting those two counters 2 and 3. That is, the central processing unit starts those two counters by accessing the register twice.
In the prior counter control system, as described above, the need of starting a plurality of counters produced during the associated processing requires a plurality of accesses for writing the information serving to start those counters in the register. In particular, when the object to be controlled requires a higher processing speed, it is needed to control a relative time difference between terminal count signals from the respective counters. Upon this control of the relative time difference, it is necessary to take into consideration not only a difference between the set counts of the counters 2 and 3 but a relative time difference between the first writing (writing of the information for starting the counter 2) and the second writing (that for starting the counter 3). The prior counter control system thus suffers from problems of, for example, complicating the control software to make demonstration of the real time property thereof (that to recognize the time when the central processing unit accesses the register within the whole very short processing time) difficult. So, in order to operate the control object at a very high processing speed, the time difference between the starts of the counters 2 and 3 is subtracted from the absolute time of the start of the counter 3. Hereby, the counters 2 and 3 are operated apparently so as to be simultaneously started. However, provided the event speed of the control object responsive to the terminal count signal is made very high, prior control software is unsatisfactory to operate that control object. | {
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Gas turbine engines are employed in a variety of applications, such as aircraft, and marine vessels, among others. The gas turbine engines generate a thrust from a fluid flow by first compressing an intake air within a compression unit. The compression unit utilizes a series of bladed discs or bladed rings for compressing the intake air. The compression unit supplies the compressed air to be mixed with a fuel mixture for combustion in a combustion unit. The resulting hot, high pressure gaseous mixture is expanded through a turbine portion to extract energy which drives the compressors and a propulsor such as a fan or propeller. Energy may also be extracted in the form of electrical power.
The bladed discs are a unitary construction having a disc (or a drum) and a number of blades spaced apart from each other. If the disc and the blade are integrated as a single piece, weight saving may be achieved. As a result, non-mechanical methods of joining the blades have been proposed, wherein the bladed discs are machined from a single forged piece. However, such methods suffer from manufacturing challenges due to less efficient utilization of expensive materials and expensive forging machinery.
Due to technical challenges associated with a high temperature environment, the bladed discs are required to be fabricated with dissimilar materials. However, there are technical challenges in joining two dissimilar materials. For example, joining of the dissimilar materials, i.e. a blade and disc alloys having different crystal structures, differences in thermal processing (i.e. heat treatment) requirements and difficulty in joining using a solid state or melting processes, such as a fusion welding. Further, the fusion welding may give unfavorable post weld mechanical properties due to a heat affected zone and mixing of alloys, increased grain size and lack of post weld homogenisation heat treatment. Furthermore, the dissimilar materials have different characteristics, i.e. weld induced residual stress or optimum material condition (e.g. aging) and hence there are always challenges in joining the dissimilar materials. Furthermore, the welding procedures of the dissimilar materials may require large and costly setups. Therefore, there is a need for an improved bladed disc that is fabricated from the dissimilar materials and further a method of manufacturing the same is proposed. | {
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1.1 Field of the Invention
The present invention relates generally to transgenic plants having insecticidal capabilities, and to DNA constructs utilized to transfer genes conferring insect resistance into plant genomes. More specifically, the present invention relates to a method of expressing insecticidal proteins in plants transformed with a B. thuringiensis δ-endotoxin encoding gene, resulting in effective control of susceptible target pests.
1.2 Description of Related Art
1.2.1 Methods of Controlling Insect Infestation in Plants
The Gram-positive soil bacterium B. thuringiensis is well known for its production of proteinaceous parasporal crystals, or δ-endotoxins, that are toxic to a variety of Lepidopteran, Coleopteran, and Dipteran larvae. B. thuringiensis produces crystal proteins during sporulation which are specifically toxic to certain species of insects. Many different strains of B. thuringiensis have been shown to produce insecticidal crystal proteins. Compositions comprising B. thuringiensis strains which produce proteins having insecticidal activity have been used commercially as environmentally-acceptable topical insecticides because of their toxicity to the specific target insect, and non-toxicity to plants and other non-targeted organisms.
δ-endotoxin crystals are toxic to insect larvae by ingestion. Solubilization of the crystal in the midgut of the insect releases the protoxin form of the δ-endotoxin which, in most instances, is subsequently processed to an active toxin by midgut protease. The activated toxins recognize and bind to the brush-border of the insect midgut epithelium through receptor proteins. Several putative crystal protein receptors have been isolated from certain insect larvae (Knight et al., 1995; Gill et al., 1995; Masson et al., 1995). The binding of active toxins is followed by intercalation and aggregation of toxin molecules to form pores within the midgut epithelium. This process leads to osmotic imbalance, swelling, lysis of the cells lining the midgut epithelium, and eventual larvae mortality.
1.2.2 Transgenic B. thuringiensis δ-Endotoxins as Biopesticides
Plant resistance and biological control are central tactics of control in the majority of insecticide improvement programs applied to the most diverse crops. With the advent of molecular genetic techniques, various δ-endotoxin genes have been isolated and their DNA sequences determined. These genes have been used to construct certain genetically engineered B. thuringiensis products that have been approved for commercial use Recent developments have seen new δ-endotoxin delivery systems developed, including plants that contain and express genetically engineered δ-endotoxin genes. Expression of B. thuringiensis δ-endotoxins in plants holds the potential for effective management of plant pests so long as certain problems can be overcome. These problems include the development of insect resistance to the particular Cry protein expressed in the plant, and development of morphologically abnormal plants because of the presence of the transgene.
Expression of B. thuringiensis δ-endotoxins in transgenic cotton, corn, and potatoes has proven to be an effective means of controlling agriculturally important insect pests (Perlak et al., 1990; Koziel et al., 1993; Perlak et al., 1993). Transgenic crops expressing B. thuringiensis δ-endotoxins enable growers to significantly reduce the application of costly, toxic, and sometimes ineffective topical chemical insecticides. Use of transgenes encoding B. thuringiensis δ-endotoxins is particularly advantageous when insertion of the transgene has no negative effect on the yield of desired product from the transformed plants. Yields from crop plants expressing certain B. thuringiensis δ-endotoxins such as Cry1A or Cry3A have been observed to be equivalent or better than otherwise similar non-transgenic commercial plant varieties. This indicates that expression of some B. thuringiensis δ-endotoxins does not have a significant negative impact on plant growth or development. This is not the case, however, for all B. thuringiensis δ-endotoxins that may be used to transform plants.
The use of topical B. thuringiensis-derived insecticides may also result in the development of insect strains resistant to the insecticides. Resistance to Cry1A B. thuringiensis δ-endotoxins applied as foliar sprays has evolved in at least one well documented instance (Shelton et al., 1993). It is expected that insects may similarly evolve resistance to B. thuringiensis δ-endotoxins expressed in transgenic plants. Such resistance, should it become widespread, would clearly limit the commercial value of corn, cotton, potato, and other germplasm containing genes encoding B. thuringiensis δ-endotoxins. One possible way to both increase the effectiveness of the insecticide against target pests and to reduce the development of insecticide-resistant pests would be to ensure that transgenic crops express high levels of B. thuringiensis δ-endotoxins (McGaughey and Whalon, 1993; Roush, 1994).
In addition to producing a transgenic plant which expresses B. thuringiensis δ-endotoxins at high levels, commercially viable B. thuringiensis genes must satisfy several additional criteria. For instance, expression of these genes in transgenic crop plants must not reduce the vigor, viability or fertility of the plants, nor may it affect the normal morphology of the plants. Such detrimental effects have two undesired results: they may interfere with the recovery and propagation of transgenic plants; they may also impede the development of mature plants, or confer unacceptable agronomic characteristics.
There remains a need for compositions and methods useful in producing transgenic plants which express B. thuringiensis δ-endotoxins at levels high enough to effectively control target plant insect pests as well as prevent the development of insecticide-resistant pest strains. A method resulting in higher levels of expression of the B. thuringiensis δ-endotoxins will also provide the advantages of more frequent attainment of commercially viable transformed plant lines and more effective protection from infestation for the entire growing season.
There also remains a need for a method of increasing the level of expression of B. thuringiensis δ-endotoxins which does not simultaneously result in plant morphological changes that interfere with optimal growth and development of desired plant tissues. For example, the method of potentiating expression of the B. thuringiensis δ-endotoxins in corn should not result in a corn plant which cannot optimally develop for cultivation. Achievement of these goals such as high expression levels as well as recovery of morphologically normal plants has been elusive, and their pursuit has been ongoing and an important aspect of the long term value of insecticidal plant products. | {
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This invention relates to starting circuits for electric motors having a main winding and a start winding and, more particularly, to a circuit which continuously monitors an average value of the magnitude of current in the main winding for switching electric power to the start winding.
A common form of electric motor is the induction motor which is manufactured in fractional horsepower capacities typically in the range of from one-quarter horsepower to one horsepower. Such motors are provided with two windings, one winding being the main winding and the other winding being a start winding, also known as a phase or auxilliary winding. The main winding continuously draws alternating current from a source of electric power throughout the operation of the motor. The start winding is required in addition to the main winding for generating a rotating torque field in order to initiate rotation of the motor shaft after which the start winding is disconnected from the source of power. In some motors, a capacitor may be included in series with the start winding, such motor being known as a split-phase motor or capacitor-start motor. In either case, the start winding must be energized for activation of the motor in the event of a stall or when initiating operation of the motor. The start winding is not to be energized during continuous operation of the motor to avoid burnout of the start winding. Also, there is no need for the start winding during continuous operation of the motor become rotation of the rotor in cooperation with the magnetic fields of the main winding induces the necessary rotating torque field for maintaining rotation of the rotor under load.
In order to disconnect the start winding from the source of power after rotation of the motor has commenced, various forms of circuitry have been employed. Some of these circuits take advantage of the relationship between main winding current and motor speed. The main winding current has a maximum value when the rotor is stationary, this value of current being referred to sometimes as a locked-rotor current. As the rotor begins to rotate, the current in the main winding begins to drop such that, at 75% of full speed of rotor rotation, the main winding current has dropped approximately 20% in magnitude. At full speed, the main winding current drops to a magnitude in the range of one-sixth to one-quarter of the locked-rotor current. One form of motor control circuit makes use of this relationship and operates with a threshold based on a testing of a specific model and size of motor. A relay responsive to the motor current is set to operate at the threshold to disconnect the start winding. Alternatively, an electronic switch set to the predetermined threshold has also been employed to disconnect the start winding. Methods of measuring the main winding current include the use of a sense resistor in series with the winding, as well as computerized circuitry which calculates peak value of the current based on measurements of the slope of the current waveform.
A problem arises in that the use of a fixed value of threshold is disadvantageous in that such threshold must be preset for each size and type of motor. In addition, such setting of the threshold presupposes that the operating voltage provided by a power supply will have its stated value. However, as is well known, the voltages of electric power sources, such as an incoming residential power line, may vary considerably depending on the loading of the line. Also, the characteristics of the motor itself may change in the event that the motor becomes heated. Also, computerized circuitry tends to be excessively costly.
A further disadvantage of the foregoing control circuitry lies in the fact that some of these circuits are designed to operate with initial values of current established when the motor is first activated. In the event of a stall due to a momentary overload, an operator must activate a switch to restart the motor. This is also true of starting circuits employing a timer. It is also noted that the circuitry employing a fixed value of threshold suffers from the disadvantage that it is not interchangeable among the various sizes and types of motors because of different requirements for specific settings of th values of threshold for the different motors. | {
"pile_set_name": "USPTO Backgrounds"
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The present invention relates to vehicle fairings. More specifically, the present invention relates to vehicle fairings for use with air conditioning units. Fairings help to improve the coefficient of drag for a vehicle and also can improve the aesthetic appeal of a vehicle. | {
"pile_set_name": "USPTO Backgrounds"
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This invention relates to a chair construction wherein the structural support members are encased by a soft cushioning layer of foamed plastic or the like.
In prior art open chairs or arm chairs the seating bowl typically consists of an approximately horizontal seating surface and a backrest, the latter being integral with the seating surface or separately supported adjacent thereto as an individual component and sometimes adjustable in height. In many arm chairs a headrest has also been disposed above the backrest, again either integral therewith or separately adjustable in height. The legs or foot supports of such chairs are found in many different forms according to both practical and stylistic or appearance considerations. Thus, for example, both open chairs and arm chairs with four conventional legs or with a central column support and radially extending feet are known, both with or without rollers or casters mounted on the ends of such legs or feet.
In the case of office furniture for desks or typewriter tables the central support column construction with a star-shaped foot configuration, typically having five projecting feet, has been widely adopted. The advantages of such a construction are that the seating surface can easily be adjusted as to height and/or tilt resiliency about a vertical axis, and because a five footed configuration offers a relatively large support base area and is less prone to tipping as when the occupant's center of gravity falls outside of the base area.
To increase the support base area the foot projections are often extended up to 10 centimeters or more beyond or outside of the peripheral area of the seating bowl. When such chairs are equipped with rollers or casters, however, a disadvantage arises in that the projecting ends of the feet often strike and damage other furniture, walls, etc. when the position of the chair is carelessly shifted or moved. Such lengthy feet must also be constructed in a very solid and sturdy manner in order to effectively transmit the weight of the occupant acting on the center support post or column out to the floor engaging rollers or casters at the extremities of the feet. Such foot constructions often involve bent metal stock shaped according to aesthetic considerations, either square or rectangular in cross-section with rounded edges. Despite such edge rounding, however, the rigid metal projections often injuriously strike the feet or ankles of the occupant. | {
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1. Field of the Invention
The present invention relates, in general, to photonic devices, and more particularly to improved laser devices and methods for fabricating them.
2. Description of the Background Art
One of the remaining problems in obtaining low-cost single lateral mode semiconductor lasers is controlling the lateral beam propagating in the laser cavity so that only a single lateral mode is allowed to operate over a wide range of currents and temperatures. One type of laser that has successfully solved this problem is the buried heterostructure laser; however, this success is at the expense of the need to regrow the semiconductor material after an initial patterning. Ridge lasers have eliminated the need for this regrowth; however, there are limitations placed on the width of the ridge as well as the depth to which the ridge can be etched while still allowing a single lateral mode behavior.
Semiconductor, or solid state, lasers are typically fabricated by growing the appropriate layered semiconductor material on a substrate through Metalorganic Chemical Vapor Deposition (MOCVD) or Molecular Beam Epitaxy (MBE) to form an active layer parallel to the substrate surface. The material is then processed with a variety of semiconductor processing tools to produce a laser cavity incorporating the active layer and incorporating metallic contacts attached to the semiconductor material. Laser mirror facets are typically formed at the ends of the laser cavity by cleaving the semiconductor material to define edges or ends of a laser optical cavity so that when a bias voltage is applied across the contacts, the resulting current flow through the active layer causes photons to be emitted out of the faceted edges of the active layer in a direction perpendicular to the current flow. Since the wafer is cleaved into bars to form the laser facets, conventional lithographical techniques on the wafer cannot be used to further process the lasers.
The problems encountered in semiconductor processing due to the need to cleave laser facets are overcome in U.S. Pat. No. 4,851,368, which discloses a process for forming the mirror facets of semiconductor lasers through etching, allowing lasers to be monolithically integrated with other photonic devices on the same substrate. This work was further extended and a process for fabricating a ridge laser process based on etched facets was disclosed in “Monolithic AlGaAs—GaAs Single Quantum-Well Ridge Lasers Fabricated with Dry-Etched Facets and Ridges”, IEEE Journal of Quantum Electronics, volume 28, No. 5, pages 1227-1231, May 1992. These processes were further improved upon in U.S. patent application Ser. No. 11/356,203 of Alex A. Behfar, filed Feb. 17, 2006, and entitled “High Reliability Etched-Facet Photonic Devices” in which high reliability etched-facet photonic devices are described. However, there is a need for a process for fabricating a photonic device such as a laser without the need for regrowth of the semiconductor material, while providing spatial lateral control of the laser output apart from the etch depth and width of the ridge, and such a laser is extremely desirable. | {
"pile_set_name": "USPTO Backgrounds"
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The semiconductor integrated circuit (IC) industry has experienced rapid growth. Technological advances in IC materials and design have produced generations of ICs where each generation has smaller and more complex circuits than the previous generation. However, these advances have increased the complexity of processing and manufacturing ICs and, for these advances to be realized, similar developments in IC processing and manufacturing are needed.
In the course of IC evolution, functional density (i.e., the number of interconnected devices per chip area) has generally increased while geometry size (i.e., the smallest component (or line) that can be created using a fabrication process) has decreased. This scaling down process generally provides benefits by increasing production efficiency and lowering associated costs. Such scaling-down also produces a relatively high power dissipation value, which may be addressed by using low power dissipation devices such as complementary metal-oxide-semiconductor (CMOS) devices. CMOS devices have typically been formed with a gate oxide and polysilicon gate electrode. There has been a desire to replace the gate oxide and polysilicon gate electrode with a high-k gate dielectric and metal gate electrode to improve device performance as feature sizes continue to decrease. However, it has been observed that multiple metal layers of the metal gate exhibit high gate resistance which can increase RC delay of the circuit and degrade device performance. | {
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The present invention relates generally to the field of children's toys. More particularly, the invention relates to a portable enclosure for toys and/or sand adapted for use by children or others in a manner that prevents spillage of the sand or toys without reducing the enjoyment to the user. The present invention further relates to a method of play that provides entertainment and enjoyment without the attendant mess associated with conventional play areas such as sand boxes.
Children of all ages love to play in the sand. Sand is a stimulating, creative and inventive tool. Sandboxes provide children with hours of fun and education. Unfortunately, while playing in traditional sandboxes, children get sand on themselves and the play area, which is very messy and difficult to clean-up. Also, conventional sand boxes are not freely portable without concern of spilling sand and/or toys therefrom.
Similarly, when using toys, such as interconnectable building blocks and the like, children typically scatter the toys throughout a room or other area. This, obviously, is unattractive, results in lost toy pieces, and can present a dangerous situation due to the chance that a child at play will stumble over a misplaced toy.
Also, conventional sand boxes are not suited for indoor use because they are unsightly and messy. Therefore, they are used outdoors which prevents use during inclement weather or at night. Furthermore, sand in conventional outdoor sandboxes is easily contaminated.
In light of the foregoing specifically noted deficiencies and others associated with conventional sand boxes and play areas, a need has been identified for a no-mess indoor enclosure adapted for holding sand and/or toys that facilitates play with the sand or toys without allowing same to escape or be removed from the enclosure. A need has also been identified for such an enclosure that is usable indoors or outdoors and that is easily portable from one location to another without fear that the contents will be spilled. Also, a need has been identified for such a no-mess indoor portable sandbox and toy enclosure that is highly aesthetically pleasing so that it enhances the surrounding area, and that is usable by multiple people simultaneously. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
A coin-operated vending machine of the type including a coin tray disposed adjacent the coin receiver.
2. Description of the Prior Art
A coin-operated vending machines typically include a switching device having a coin receiver and responsive to metallic coins inserted into the coin receiver for actuating a dispenser. Some machines include a coin tray disposed adjacent the coin receiver for storing coins for use in the machine. An example of such a machine is disclosed in U.S. Pat. No. 4,846,333 to Kissick.
Some coin-operated vending machines are used in open air environments, which can be very hostile, as in the winter in the northern United States. An example of such a machine is disclosed in U.S. Pat. No. 5,857,417 to Hart wherein a coin-operated machine dispenses air in a gasoline station. Such coin-operated vending machines are also used to dispense water in self serve car washes. Using coins in such cold environments to dispense water can be troublesome if the temperature is below freezing. | {
"pile_set_name": "USPTO Backgrounds"
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Field of the Invention
Embodiments of the present invention generally relate to methods and apparatus for operating a downhole tool.
Description of the Related Art
A wellbore is formed to access hydrocarbon bearing formations, e.g. crude oil and/or natural gas, by the use of drilling. Drilling is accomplished by utilizing a drill bit that is mounted on the end of a tubular string, such as a drill string. To drill within the wellbore to a predetermined depth, the drill string is often rotated by a top drive or rotary table on a surface platform or rig, and/or by a downhole motor mounted towards the lower end of the drill string. After drilling to a predetermined depth, the drill string and drill bit are removed and a section of casing is lowered into the wellbore. An annulus is thus formed between the string of casing and the formation. The casing string is temporarily hung from the surface of the well. The casing string is cemented into the wellbore by circulating cement into the annulus defined between the outer wall of the casing and the borehole. The combination of cement and casing strengthens the wellbore and facilitates the isolation of certain areas of the formation behind the casing for the production of hydrocarbons.
It is common to employ more than one string of casing in a wellbore. In this respect, the well is drilled to a first designated depth with a drill bit on a drill string. The drill string is removed. A first string of casing is then run into the wellbore and set in the drilled out portion of the wellbore, and cement is circulated into the annulus behind the casing string. Next, the well is drilled to a second designated depth, and a second string of casing or liner, is run into the drilled out portion of the wellbore. If the second string is a liner string, the liner is set at a depth such that the upper portion of the second string of casing overlaps the lower portion of the first string of casing. The liner string may then be fixed, or “hung” off of the existing casing by the use of slips which utilize slip members and cones to frictionally affix the new string of liner in the wellbore. The second casing or liner string is then cemented. This process is typically repeated with additional casing or liner strings until the well has been drilled to total depth. In this manner, wells are typically formed with two or more strings of casing/liner of an ever-decreasing diameter.
As more casing/liner strings are set in the wellbore, the casing/liner strings become progressively smaller in diameter to fit within the previous casing/liner string. In a drilling operation, the drill bit for drilling to the next predetermined depth must thus become progressively smaller as the diameter of each casing/liner string decreases. Therefore, multiple drill bits of different sizes are ordinarily necessary for drilling operations. As successively smaller diameter casing/liner strings are installed, the flow area for the production of oil and gas is reduced. Therefore, to increase the annulus for the cementing operation, and to increase the production flow area, it is often desirable to enlarge the borehole below the terminal end of the previously cased/lined borehole. By enlarging the borehole, a larger annulus is provided for subsequently installing and cementing a larger casing/liner string than would have been possible otherwise. Accordingly, by enlarging the borehole below the previously cased borehole, the bottom of the formation can be reached with comparatively larger diameter casing/liner, thereby providing more flow area for the production of oil and/or gas. Underreamers also lessen the equivalent circulation density (ECD) while drilling the borehole.
In order to accomplish drilling a wellbore larger than the bore of the casing/liner, a drill string with an underreamer and pilot bit may be employed. Underreamers may include a plurality of arms which may move between a retracted position and an extended position. The underreamer may be passed through the casing/liner, behind the pilot bit when the arms are retracted. After passing through the casing, the arms may be extended in order to enlarge the wellbore below the casing. | {
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As computers advance, integration of platforms and their components become a larger and more complex task. Designers of computer systems prefer platforms to be modular and upgradeable, so pieces of the platform may be updated without having to replace the whole system. In light of this industry model, basic input/output software (BIOS) used to initially boot a platform is typically stored on a FLASH device. Therefore, if a platform's configuration needs to be changed and the BIOS needs to be updated, a memory device is erased and updated with new code/software.
Previously, memory devices were not erased regularly, as it was not necessary to update the BIOS frequently. However, new usage models of a platform's BIOS has changed the frequency in which the BIOS is erased. Examples of the new usage models include, expanding the use of the BIOS into the operating system (OS) space and using the FLASH as a repository for configuration related data.
Although today's FLASH devices have the ability to be rewritten with a good level of reliability, FLASH devices are still susceptible to write-failure limitations. Moreover, the increase in the regularity that FLASH devices are updated exposes an inherent fragility that was not exhibited previously due to the static nature of a FLASH device's usage.
Upon manufacture and frequent flashing, a FLASH device may develop bad blocks, i.e. blocks that result in a read or write failure upon access. Bad blocks may cause failure in initialization of the platform or other configuration problems. Currently, bad blocks in a FLASH potentially cause the whole FLASH device to be scrapped and replaced, which is inefficient and expensive. | {
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Injection nozzles are known, both in the form of partially squeezable hole-type nozzles and in the form of annular gap nozzles. In the known gap nozzles, a needle, which is axially adjustable, is arranged concentrically in the nozzle housing, and, together with the concentric nozzle opening of the nozzle housing, defines a variable gap with respect to the injection mixing chamber. This gap can be altered by means of adjustable stops. The reaction components to be mixed flow from the nozzle opening or the annular gap into an injection mixing chamber in which they are mixed together. The energy required for injection mixing is substantially dependent on the rate of flow, the viscosity, the solubility and the metering ratio of the reaction components. In addition to the distance and the position of the injection nozzles relative to each other, the shape and, in particular, the cross-sectional area of the nozzle openings (or the cross-section of flow) have a great influence on the degree of mixing. The nozzle openings (or their cross-sectional areas) are adjusted manually depending upon the rate of flow and viscosity of the reaction components passing therethrough. Adjustment is usually carried out after a largely subjective judgment of the degree of mixing. Such adjustments can be conducted, for example, by axial adjustment and fixing of the nozzle needle.
It has proved helpful to use the hydraulic pressure which has built-up between the metering pump and injection nozzle as a measure of the mixing energy available for injection mixing purposes. The minimum pressure needed for mixing is dependent on the above-mentioned parameters. Such pressure normally lies between 50 and 150 bar, but can reach 350 bar or even more in some cases. Since deviations from the optimum operating pressure in the metering system impair the degree of mixing, a constant, securely adjusted metering rate and viscosity of the reaction components and also a constant, securely adjusted opening cross-sectional area of the associated injection nozzles are preferably adopted during injection mixing.
A significant disadvantage of this mode of operation is that it is not possible to effect significant change in the metered quantity of reaction components per unit time. This change may be desirable in order to adapt the metered quantity of the resulting multi-component reaction mixture optimally to the geometric conditions within the mold cavities during the mold filling process.
The object of the invention is to allow a significant change in the metered quantity of reaction components per unit time, adapted to the geometric conditions within the mold cavity, of multi-component reaction materials, which may be highly reactive, during a mold-filling process even when using injection mixers, without impairing the mixed product of the reaction mixture produced in the injection mixers. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
Exemplary embodiments of the present invention relate to a liquid crystal display (“LCD”) panel and a method of manufacturing the LCD panel. More particularly, exemplary embodiments of the present invention relate to an LCD panel used in a transflective-type LCD device and a method of manufacturing the LCD panel.
2. Description of the Related Art
Generally, a liquid crystal display (“LCD”) device may be classified as a transmissive-type LCD device, a reflective-type LCD device or a transflective-type LCD device. Due to high visibility and color reproducibility of the transmissive-type LCD device in an indoor space, the transmissive-type LCD device has been widely used. However, the visibility of the transmissive-type LCD device is decreased outdoors, and power consumption of the transmissive-type LCD device is high.
On the other hand, the reflective-type LCD device has high visibility outdoors and does not employ an internal light source, for example, a backlight, so that the reflective-type LCD has the benefit of having low power consumption. However, the visibility of the reflective-type LCD device is decreased in a dark environment, such as an indoor space.
Thus, a transflective-type LCD device has been developed, which has the merits of 75
both the transmissive-type LCD and the reflective-type LCD device. However, the transflective-type LCD has detriments in its optical structure and manufacturing aspects as compared with the transmissive-type LCD and the reflective-type LCD device. That is, a light path passing through a liquid crystal layer only once in a transmissive area of the display; however, in a reflective area of the display incident light is reflected against a reflective plate back to the liquid crystal layer so that the light path in this part of the display passes through the liquid crystal layer at least twice. Thus, a difference of phase delay exists in the two areas.
In order to solve the above problems, the transflective-type LCD is designed so that a cell gap of a liquid crystal layer corresponding to the transmissive area is twice as large as that of a liquid crystal layer corresponding to the reflective area by using a twisted nematic (“TN”) mode. However, a liquid crystal film structure, which is used to adjust a light path of a reflective area and a transmissive area and narrow viewing angle of the TN mode, and a rubbing direction of an initial liquid crystal have a low-TN mode that is a TN mode of which an initial twist angle is small, so that transmissivity may be low. In order to overcome the above disadvantages, a vertical alignment mode may be used. However, transmittance versus applied voltage curve (V-T curve) characteristics and reflectivity versus applied voltage curve (V-R curve) characteristics corresponding to the reflective area and the transmissive area may need to be adjusted.
When thin-film transistors (“TFTs”) that are independently employed in the reflective area and the transmissive area to adjust V-T curve characteristics and V-R curve characteristics of the reflective and the transmissive areas, an aperture ratio may be decreased and manufacturing costs may be increased. Moreover, when an insulation layer is formed in the reflective area to decrease an electric field for driving liquid crystal molecules, a difference of threshold voltage may be generated at low gradation. | {
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1. Field of the Invention
The present invention relates to a developing apparatus wherein a developer is conveyed while being agitated by screw-like agitating members having different numbers of threads, as well as an image formation apparatus using the developing apparatus.
2. Description of the Prior Art
In an image formation apparatus, using a developing apparatus which serves as a developer supply means, a developer is fed to an electrostatic latent image formed on an image bearing member to develop the electrostatic latent image. In a developing apparatus using a two-component developer comprising a carrier and a toner, it is desirable that the toner and the carrier be conveyed in a satisfactorily agitated state. In view of this point, there has been proposed a developing apparatus of a twin screw agitating type wherein the interior of a case is divided by a partition wall into a first space positioned on a toner supply side for the image bearing member and a second space into which is fed a replenishing toner, with screw-like agitating members being disposed in parallel within the spaces.
According to the developing apparatus of a twin screw agitating type, a developer is conveyed while being agitated by a first agitating member disposed in the first space and a second agitating member disposed in the second space and the developer thus conveyed is fed into the spaces from delivery portions formed at end portions of the agitating members, thus being circulated. In such a twin screw agitating type developing apparatus, a screw trace, which is caused by, for example, unevenness in the density of the screw pitch, is apt to occur at the time of development of an image having a high image ratio. Therefore, attempts have been made to agitate and convey a developer by using multiple-thread screws as the first and second agitating members.
With such multiple-thread screws as the first and second agitating members, there occurs a new problem although the occurrence of screw traces can he prevented. For attaining a satisfactory development in the twin screw agitating type developing apparatus, it is important that a sufficient developer be fed to the first space having the first agitating member. However, if the multiple-thread screws are used as agitating members, the area occupied by the screws in each space is large and the amount of developer loaded into the developing apparatus becomes smaller, resulting in decrease of the amount of developer fed to the first space positioned on the toner supply side.
If agitating members are screws having an identical number of threads and an identical pitch, it is theoretically possible to convey an identical amount of developer at an identical speed. However, if the screws have areas too large with respect to the aforementioned spaces, the developer becomes more bulky and the agitating members are buried in the developer. If such a state occurs, there is formed an area on which each of the agitating members cannot exhibit its conveying force. This causes a difference in the developer conveying speed as compared with the case where the agitating members are not buried. As a result, the developer circulating balance is lost and the developer stays in the end portions of the spaces.
Even at the same conveying speed, if agitating members have different numbers of threads, i.e., different numbers of blades, the screw having a larger number of threads conveys less developer. For example, if the second agitating member has a smaller number of threads and the first agitating member has a larger number of threads, the developer will stay in the vicinity of a developer delivery portion for delivery of developer from the second space having the second agitating member to the first space having the first agitating member. If the delivery portion with the developer thus staying therein overlaps an image forming area, a larger amount of developer than necessary is fed into the first space and the developer may leak out of the apparatus from near a portion opposed to the image bearing member.
A certain developing apparatus is provided with a toner concentration detecting means for detecting and outputting a toner concentration in a developer. However, if the way in which the developer stays within a space changes, a greater output difference results, disabling to accurately detect a toner concentration.
It is an object of the present invention to provide a developing apparatus and an image formation apparatus in which the occurrence of screw pitch traces and unsatisfactory development caused by an insufficient amount of developer fed are extremely diminished
It is another object of the present invention to provide a developing apparatus and an image formation apparatus capable of preventing leakage of a developer to the exterior of the apparatus.
It is a further object of the present invention to provide a developing apparatus and an image forming apparatus capable of detecting a toner concentration accurately even if there is a change in the way of staying of a developer.
For achieving the above-mentioned objects, the present invention provides a developing apparatus comprising: a case divided into a first space located at a developer supply side for supplying the developer to an image bearing member and a second space for receiving a replenishing toner; a first and a second agitating member arranged in the first and the second spaces in such a manner that the first and the second agitating members are positioned parallel to each other and are driven to rotate to agitate and convey the developer,
wherein the first agitating member arranged in the first space is a screw member having n threads (nxe2x89xa72), and the second agitating member arranged in the second space is a screw member having (nxe2x88x92x) threads (xxe2x89xa70). Since the second agitating member has a smaller number of threads than the first agitating member, the volume thereof in the second space decreases and the bulk (height) of the developer is prevented from becoming larger.
The developing apparatus may further comprise: a first delivery portion for feeding the developer from the first space into the second space; and a second delivery portion for feeding the developer from the second space into the first space, which secondary delivery portion is positioned outside an image formation area of the image bearing member. According to this construction, the position where the developer is delivered from the second space to the first space lies exteriorly of the image forming area of the image bearing member, with no delivery of the developer within the image forming area.
For diminishing the developer conveying capacity of the second agitating member, a non-screw portion may be formed at a portion of the second agitating member located at a predetermined interval in the convey direction of the developer conveyed by the second agitating member, thereby suppressing the convey force.
Likewise, for diminishing the developer conveying capacity of the second agitating member, rotation speed V1 of the first agitating member is set greater than rotation speed V2 of the second agitating member. This relation can be established by rotating the first and second agitating members each individually with use of different drive sources for rotation or, in case of using a single drive source for rotation, with use of gears having a different number of teeth or pulleys different in speed change ratio in an integrally rotatable manner with the first and second agitating members. As a result, the amount of developer conveyed per unit time by the second agitating member is kept smaller than that by the first agitating member.
Further, for diminishing the developer conveying capacity of the second agitating member, it is preferable to narrow the screw pitch of the second agitating member. This is also effective because the amount of developer conveyed per unit time decreases.
In the case where the developing apparatus includes toner concentration detecting means to detect and output the concentration of toner contained in the developer, the toner concentration detecting means having a detection surface which faces the interior of the second space, it is preferable that the toner concentration detecting means be disposed closer to the first delivery portion than to the second delivery portion with respect to the center of the image forming area. According to this construction, even if the way of staying of the developer changes on the second delivery portion side, this can be made less influential on the toner concentration detecting means.
According to another aspect of the present invention, there is provided an image forming apparatus having an image bearing member and developer supply means for supplying a developer to an electrostatic latent image formed on the image bearing member to develop the electrostatic latent image, wherein a developing apparatus is used as the developer supply means, the developing apparatus having a screw member of n threads (nxe2x89xa72) as a first agitating member disposed within a first space and a screw member of (nxe2x88x92x) threads (xxe2x89xa70) as a second agitating member disposed within a second space to receive the supply of a replenishing toner. According to this construction, since the number of threads of the second agitating member is smaller than that of the first agitating member, the volume of the second agitating member in the second space decreases.
In case of using as the developer supply means a developing apparatus having a first delivery portion for feeding the developer from the first space to the second space and a second delivery portion for feeding the developer from the second space to the first space, the second delivery portion being positioned on an outer side with respect to an image forming area of the image bearing member, the position where the developer is delivered from the second space to the first space lies exteriorly of the image forming area of the image bearing member, with no delivery of the developer within the image forming area.
In case of using a developing apparatus as the developing supply means, the developing apparatus having non-screw portion at a portion of the second agitating member which portion is positioned in a predetermined section in the direction of conveyance of the developer conveyed by the second agitating member, the developer conveying capacity of the second agitating member is kept low by the non-screw portion.
In case of using as the developer supply means a developing apparatus wherein if the rotational speed of the first agitating member is V1 and that of the second agitating member is V2, there is established a relation of V1 greater than V2, the developer conveying capacity of the second agitating member decreases.
In case of using as the developer supply means a developing apparatus wherein the screw pitch of the second agitating member is set narrow, the amount of the developer fed per unit time decreases.
Further, as the developer supply means there may be used a developing apparatus including a toner concentration detecting means for detecting and outputting the concentration of toner contained in the developer, the toner concentration detecting means having a detection surface which faces the interior of the second space and being disposed closer to the first delivery portion rather than the second delivery portion with respect to the center of the image forming area. In this case, even if the way of staying of the developer changes on the second delivery portion side, this can be made less influential on the toner concentration detecting means. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
The present invention relates to a method for smelting reduction of iron ore, and particularly to a method wherein carbonaceous material is used as both of fuel and a reducing agent and the iron ore which is being smelted and reduced in a basic oxygen furnace and an apparatus therefor.
2. Description of the Related Arts
Smelting reduction method has recently been developed as a substitution for a blast furnace iron-making method, to overcome some disadvantages in that the blast furnace iron-making method requires not only an expensive construction cost but also a vast construction site.
In a prior art smelting reduction method, iron ore is prereduced by means of an exhaust gas, and then the pre-reduced iron ore is charged together with carbonaceous material and flux into a smelting reduction furnace. Furthermore, oxygen gas and stirring gas are blown into the smelting reduction furnace. Thus, the carbonaceous materials is smelted thanks to the precharged molten metal and, at the same time, C contained in the carbonaceous material is oxidated by the oxygen gas. Through the heat produced by this oxidation, the ore is smelted and reduced by means of C contained in the carbonaceous materials. CO gas generating in the molten metal is post-combusted, by the oxygen gas excessively blown, into CO.sub.2 gas. The sensible heat of this CO.sub.2 gas is transferred to slag and iron particles in the slag covering the surface of the molten metal, and then, to the molten metal.
In this way, the iron ore is reduced to the molten metal. In this process, in order to lighten the load of reduction process in a smelting reduction furnace, iron ore is prereduced, for example, at a reduction degree of 60 to 75% before the iron ore is charged into the smelting reduction furnace as disclosed in a Japanese Examined Patent Publication No. 434 06/86. Resultantly, an exhaust gas from the smelting reduction furnace becomes a low oxidated gas which is highly reductive and a large amount of the exhaust gas is forced to be required.
If iron ore before being charged into the smelting reduction furnace is prereduced at a ratio of at least 30% for the purpose of the lightening the load of reduction process of smelting reduction furnace, an oxidation degree(hereinafter referreto as "OD") of the exhaust gas from the smelting reduction furnace, where the OD is represented by the formula of "(H.sub.2 O+CO.sub.2)/(H.sub.2 +H.sub.2 O+CO+CO.sub.2)" is required to be lowered. Resultantly the amount of the exhaust gas is necessarily increased, as shown, for example, in the Japanese Examined Patent Publication No. 43406/86. This increase of the exhaust gas, naturally, increases the production cost. Consequently, to obtain the high prereduction ratio of the iron ore, the exhaust gas having a low OD as explained above is required, and still the retention time of the iron orestaying in the prereduction furnace has to become longer than that in the smelting reduction furnace. Therefore, it becomes difficult to control the balancing of cycles of charge of the prereduced iron ore and discharge of the produced molten metal. This necessarily results in restricting control range strictly in the smelting reduction furnace.
Furthermore, in order to raise a melting speed of iron ore and to obtain the speed-up of reduction of the iron ore, a method of post-combusting CO gas in the smelting reduction furnace and making use of the heat generated therefrom has conventionally been employed, wherein O.sub.2 gas for post-combustion is introduced through tuyeres placed at upper wall of the smelting reduction furnace. However, in the conventional method, although the temperature of the exhaust gas can be elevated when the ratio of the post-conbustion is raised, the sensible heat transfer to the molten metal is not sufficient. This results in being forced to discharge high temperature exhaust gas. This method has a difficulty in that such a high temperature gas will attack the inner refractory wall of the smelting reduction furnace.
Therefore, it has been hitherto a generally conceived that the OD of the exhaust gas cannot be raised so much. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Field of the Invention
The present invention relates in general to magnetic resonance tomography (MRT) as used in the medical field for the examination of patients. This invention relates in particular to a process for avoiding peripheral interference signals in spin-echo images such as e.g. the ambiguity artifact.
2. Description of the Prior Art
MRT is based on the physical phenomenon of nuclear spin resonance and has been successfully implemented in the medical field and in biophysics for more than 15 years. In this examination method, the object is exposed to a strong, constant magnetic field. The nuclear spins of the atoms in the object, which were previously randomly oriented, are thereby aligned. Radio-frequency energy can now excite these “ordered” spins to a specific oscillation. This oscillation creates in MRT the actual measurement signal, which is detected by means of suitable receiving coils. By the use of non-homogeneous magnetic fields, created by gradient coils, the measurement object in each area of interest—also called FOV (field of view)—can be encoded in all three spatial directions, which in general is called “spatial encoding.”
The recording of the data in MRT occurs in k-space (frequency domain). The MRT image in the image domain is linked with the MRT data in k-space by Fourier transformation. The spatial encoding of the object, which spans k-space, takes place by means of the gradients in all three spatial directions. In this process a differentiation is made between the slice selection (determines the exposure slice in the object, normally the z axis), the frequency encoding (determines a direction in the slice, normally the x axis), and the phase encoding (determines the second dimension within the slice, normally the y axis).
Thus, a slice e.g. in the z direction is first selectively excited by a slice selection gradient Gs or Gz. The encoding of the location information in the slice takes place by combined phase and frequency encoding by means of both of the previously mentioned orthogonal gradient fields Gr and Gp, which are created in the example of a slice excited in the z direction by the aforementioned gradient coils in the x and y directions.
One known form for recording the data in an MRT measurement (scan) is shown in FIGS. 2A and 2B. The sequence used is a spin-echo sequence. In this sequence, the magnetization of the spins is flipped in the x-y plane by a 90° excitation impulse (with defined amplitude and bandwidth). Over time, the result is a dephasing of the magnetization components, which together form the transverse magnetization in the x-y plane Mxy. After a certain period of time (e.g. ½ TE, TE is the echo time), a 180° pulse (also with defined amplitude and bandwidth) is emitted in the x-y plane so that the dephased magnetization components are mirrored without changing the precession direction and precession speed of the individual magnetization components. After another period of time (½ TE), the magnetization components point in the same direction again, i.e. the result is a regeneration of the transverse magnetization, called “rephrasing,” which is appropriately read-out. The complete regeneration of the transverse magnetization is called the spin-echo.
In order to measure an entire slice of the object to be examined, the imaging sequence is repeated N times with different values of the phase-encoding gradient GP or Gy, whereby the frequency of the magnetic resonance signal (spin-echo signal) is scanned, digitized, and stored with each sequence repetition by the Δt-clocked ADC (analog digital converter) N times in equidistant time increments Δt in the presence of the selection gradients GR or GX. In this manner, a numerical matrix is created line by line as per FIG. 2b (matrix in k-space or k matrix) with N×N data points (a symmetrical matrix with N×N points is only one example; asymmetrical matrices also can be created). An MR image of the observed slice with a resolution of N×N pixels can be reconstructed directly from this data record via a Fourier transformation.
The scanning of the k matrix (k matrices when recording several slices) for spin-echo sequences with diagnostically usable image quality typically requires several minutes of measurement time, which represents a problem for many clinical applications. For example, patients might not be able to remain immobile for the required period of time. For examinations in the thorax or the pelvic area, body movement is generally unavoidable (heart and breathing movement, peristalsis). One way to accelerate spin-echo sequences was published in 1986 as the turbo-spin-echo sequence (TSE sequence) also known by the acronym RARE (Rapid Acquisition with Relaxation Enhancement) (J. Hennig et al. Magn. Reson, Med. 3, 823–833, 1986). In this imaging procedure, which is much faster compared to the conventional aforementioned spin-echo procedure, several (multiple) echoes are created after a 90° excitation pulse, and each of these echoes is individually phase-encoded. A pulse sequence is shown in FIG. 3A for the case when seven echoes are created. The phase-encoding gradient corresponding to the Fourier line to be selected must be switched before and after each echo. In this manner, a linear scanning of the k matrix as shown in FIG. 3B takes place after a single RF excitation pulse (90°). The necessary total measurement time is shortened in this example by a factor of 7. The signal progression in FIG. 3a is shown in an idealized manner. In reality, the later echoes have increasingly smaller amplitudes due to the T2 decay of the transverse magnetization.
An even faster imaging sequence is a combination of RARE with the Half-Fourier technique, which was introduced in 1994 as the so-called HASTE sequence (Half Fourier Acquired Single Shot Turbo Spin Echo) (B. Kiefer et al., J. Magn. Reson. Imaging, 4(P), 86, 1994). HASTE uses the same basic technique as RARE, but only half of the k matrix is scanned. The other half of the k matrix is reconstructed mathematically by means of the Half-Fourier algorithm. This takes advantage of the fact that the data points of the k matrix are arranged mirror-symmetrical to the center point of the k matrix. For this reason, it is sufficient to measure only the data points of a k-matrix half and to mathematically complete the raw data matrix by mirroring with respect to the center point (and complex conjugation). In this manner, the measurement time can be reduced by half. The reduction of the recording time, however, degrades the signal-to-noise ratio (SNR) by a factor of √2.
A general problem with spin-echo sequences (SE sequences) is that the resonance condition during the radio-frequency excitation by the RF pulse is determined not only in the FOV (field of view, characterized by homogeneity of the basic field as well as linearity of the gradient fields) but also in the non-homogeneous border area of the FOV. Due to the actual inhomogeneity of the basic field and the nonlinearity of the gradient fields in the border area of the MRT device, the principle of a unique reversible assignment of each spatial point to one specific magnetic field strength is violated. This means that a generally interfering image from the inhomogeneity area in the form of an artifact superimposes the image of actual measurement field. This unwanted artifact is known as a “double-entendre artifact” and occurs in a pronounced form in particular in spin-echo sequences as a result of the spin refocusing. The “double-entendre artifact” becomes the more pronounced the shorter the extent of the basic field magnet in the z-direction. Thus, future MRT systems will tend toward shorter magnets, intensify this problem, and it will no longer be solvable with the previous measures for suppressing this artifact.
Prior strategies for reducing this type of artifact are hardware measures and pulse-sequence modifications.
Hardware measures for the RF system include determining the spatial positions with field double entendres outside the useful volume for the given magnet and gradient design. The design of the RF coils is subject to the restriction of sufficiently minimizing its sensitivity for these critical spatial positions so that a significant artifact formation is prevented. RF field distributions, however, are not always able to be appropriately designed. As an unwanted side effect, RF field inhomogeneities that impair the image quality are also created within the useful volume.
The main focuses for the design of future MR devices are shorter magnets, spaciousness, and the largest possible patient accessibility (e.g. for surgical intervention). With this type of magnetic field geometry, the necessary reversible unique correspondence between space and field are violated such that the previous hardware measures fail. For shorter magnets with a large diameter, a suitable RF coil design thus is not possible.
Pulse sequence modifications (new approaches to sequence formation) often represent the only practical solution if the direct avoidance of the drawback (here the non-monotonous magnetic field progression) reaches theoretical or technological limits or requires disproportionately high effort, which would compromise the economic efficiency of the product.
A possible form of the pulse sequence modification according to U.S. Pat. No. 6,486,668 is to bring about an artifact suppression by emitting additional so-called preparation pulses. A disadvantage of this approach is the clear reduction in the time efficiency as well as the simultaneous creation of other image quality problems in the form of parasite spin-echo signal components due to the preparation pulses.
Another form of pulse sequence modification is implemented in U.S. Patent Application Publication No. 2002/0101237, wherein artifact suppression takes place by switching the polarity switch of the selection gradients between the RF excitation pulse and the RF refocusing pulse. In contrast to conventional slice excitation of an SE sequence, the slice selection gradient, which is switched during the slice excitation by the (90°-) RF pulse, compared to the slice selection gradient, which is switched during the (180°-) refocusing pulse, is inverted as to its algebraic sign or its polarity. This causes selection of the (90°-) RF pulse as well as the (180°-) refocusing pulse to occur in the spatial domain in different non-overlapping areas. In this manner, no interfering echo signals are created. This procedure, however, has the disadvantage that it places increased technical demands on the exact temporal synchronization of RF pulses and gradient pulses as well as on the system shimming. Moreover, the simultaneous representation of different chemical components (e.g. fat and water) is only possible with a notable signal loss. | {
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1. Field of the Invention
The invention relates to currency dispensing and deposit-accepting rotary cash drawer means used as a part of automatic banking equipment in which the cash drawer rotor has a pocket which receives a requested amount of currency from a stored currency supply at "home" position, delivers the currency to an "open" position for removal, can accept deposits in the "open" position, and then moves to a "dump" position to dump the deposits into a safe or protected compartment in the banking unit, or to dump currency which may not have been removed while the rotor was at the "open" position. More particularly, the invention relates to an improved, simplified, readily adjusted and inexpensive drive, operating and control mechanism for the cash drawer rotor.
2. Description of the Prior Art
The prior construction of U.S. Pat. No. 3,880,320, of which the operating and control mechanism of the invention is an improvement, involves a direct drive motor for rotating the drawer rotor in one direction, a friction drive motor for rotating the rotor in the other direction, a pivotal motor mount plate carrying the two drive motors, and means for pivotally moving the motor mount plate between positions for engaging one or the other drive motors with the rotor. A ratchet wheel prevents rotary movement of the rotor in one direction at certain times, and separate lock pin means locks the rotor in "home" position.
It has been discovered that this prior operating and control mechanism is difficult to adjust and maintain in adjustment. Further difficulties have been encountered in controlling and coordinating the operation of the two motors. Further, the drive construction has a high cost because of the use of two drive motors of different types and kinds.
Thus, a need has developed for a rotary cash drawer operating and control mechanism for the rotary cash drawer means of a banking unit currency dispenser and depository which eliminates the difficulties that have been encountered in the operation and use of prior devices. | {
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Referring to FIG. 10, the diameter ϕ d of a hole to be drilled into a workpiece by a conventional drill bit is determined by the diameter ϕ D of the drill bit, or more specifically, the diameter ϕ d is defined by the cutting edge(s) of the drill bit. Since drill bits of a certain size can only be used to drill holes of a specific diameter, one who has drilling needs must prepare and store a large number of drill bits of various sizes. In addition, it is well known in the art that a twist drill bit as shown in FIG. 10 produces continuous and wide drilling chips during operation, especially when drilling mild steel, aluminum, aluminum alloys, or stainless steel. Such continuous chips do not break easily, tend to be stuck in the chip removing grooves, and have high thermal conductivity such that the main shaft of the controller, e.g., a machine tool, is subjected to a huge cutting load which is typically as high as 60% of the load capacity of the main shaft, and which has significant adverse effects on not only the main shaft, but also the rigidity, cutting precision, and service life of the machine tool. Should the chips get stuck and make it impossible to keep on drilling, the drilling operation must be suspended until the chips are removed.
FIG. 11 shows a conventional disposable drill bit whose disposable blades are provided with chip breaking grooves. When the material being drilled is soft, however, the chip breaking grooves may have problem breaking the drilling chips, and the chips may eventually get stuck and cause overheating. To cool the drill bit, it is typically required to inject a cutting fluid at the drill bit, but if the hole being drilled is so deep that the chips produced hinder the cutting fluid from flowing into the hole and reaching the cutting edges at the distal end of the drill bit, the temperature of the cutting edges will continue rising. This explains why a conventional drilling operation must be conducted intermittently to allow chip removal and heat dissipation. Such intermittent operation nevertheless results in low work efficiency and high processing cost.
Both drill bits described above are configured for continuous cutting and generate large, continuous chips which tend to get stuck and raise overheating issues. Moreover, a twist drill bit as well as a disposable drill bit has limitations on drilling depth, for the greater the drilling depth, the more difficult it is to discharge the chips produced. If the chips are trapped in the drill bit flutes, further drilling will be obstructed. | {
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The present invention relates to a novel nickel-base superalloy and, more particularly, to a gas turbine and a gas turbine nozzle which are formed of such a superalloy and, further, a combined power generating system employing such a gas turbine and a steam turbine.
Cobalt-base alloys have been widely used as materials of industrial gas turbine nozzles (stationary blades) because of their favorable corrosion-resistance and weldability. However, because the combustion temperature (the temperature at the inlet of a gas turbine) has recently been increased in order to improve thermal efficiency, there is an increasing need for an alloy having great high-temperature strength and thermal-fatigue resistance to replace cobalt-base alloys. Nickel-base superalloys, which are used for blades (buckets), have greater high-temperature strength and thermal-fatigue resistance than cobalt-base alloys. However, because conventional nickel-base superalloys have poor weldability, they are not very suitable materials for gas turbine nozzles, which require welding, for example, repair welding.
Nickel-base superalloys for gas turbine nozzles are disclosed in JP-A-60-10064 and U.S. Pat. No. 4,039,330, and an improved nickel-base superalloy for gas turbine nozzles in U.S. Pat. No. 4,810,467.
Although the above conventional art improves weldability of nickel-base superalloys, it provides no improvement in high-temperature strength, particularly, high-temperature strength over a long term, which is essential to increase the tolerable temperature and durability of the gas turbine nozzles. | {
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This invention relates to a device for placement between an object and a fixed supporting surface to which the object is mounted, and more particularly to such a device which provides adjustment of the position of the object relative to the fixed supporting surface. In machinery installations, it is common to provide a power source that drives a driven machine. For example, a motor or engine is often mounted adjacent a piece of equipment, such as a pump, gear reducer or the like adapted to be driven thereby. The motor and the driven device are often mounted to the same support plate fixed relative to the supporting surface, for example, a foundation, pad, or floor. In most cases, the height between the motor output shaft and motor mounting structure is different than the height between the input shaft of the driven device and its mounting structure. Placing steel shims between the fixed support plate and the motor and/or the driven device to align the motor output shaft and the input shaft of the driven device customarily accommodates this difference in height. U.S. Pat. No. 5,080,319 to Nielson discloses a mounting device placed between the motor mount and the support plate to make adjustments to this height difference.
However, prior art pumps, such as shown in FIG. 1, are manufactured with several sizes of casings 118, for example, three sizes such as 9-inch, 11-inch and 13-inch casings. When a casing size is increased and the load is also increased, a larger motor may be required. When this happens, this creates a problem. Though the casings can be readily changed, the motor mounts typically do not align with the mounting holes in the support plate for the old motor. Additionally, the height difference may be more significant and requires more than the adjustments provided by prior art devices. This typically requires the installation of a new pump skid to accommodate the new motor size and height difference between pump and motor shafts.
Thus, there exists a need to increase the versatility of a pump skid to accommodate changes to different motors when a pump casing is changed and/or the pump load is increased. | {
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1. Technical Field
The present invention relates to an inkjet printer having a choke unit for closing the ink path at a position on the ink path between the ink cartridge and the printhead.
2. Related Art
Ink ejection problems can result from air bubbles in the ink path flowing into the printhead. Inkjet printers may therefore have a bubble trap disposed to the ink path to capture any air bubbles. Such inkjet printers perform a choke cleaning operation to purge the bubbles in the bubble trap from the printhead side when the air bubbles in the bubble trap are expected to reach a preset size.
This choke cleaning operation closes the ink path at a position upstream from the bubble trap by means of a choke unit. The nozzle face of the printhead is then covered by a cap, the inside of the cap is then depressurized by a suction means, and negative pressure is produced in the ink path. The choke unit is then opened in this negative pressure state, and the bubbles in the bubble trap are discharged in a burst with ink from the ink nozzles.
An inkjet printer that performs this choke cleaning operation is described in JP-A-2003-301964.
The choke unit of the inkjet printer described in JP-A-2003-301964 has a disc disposed inside the ink path, and an electromagnet on the outside of the ink path. The disc has a support member made from a magnetic material, and moves between a closed position choking the ink path closed, and an open position where the ink path is open. To choke the ink path closed, the electromagnet is driven to attract the support member by the force of magnetic attraction and move the disc from the open position to the closed position.
Because magnetic force is inversely proportional to the distance squared, it is not easy to increase the stroke of the disc that opens and closes the ink path or to increase the magnetic force applied to the disc when using a configuration that moves a disc located inside the ink path by means of magnetic force from outside the ink path. The flow path of the ink path must therefore be narrow in the area around the choke unit, and flow resistance therefore increases in this area. Because pressure loss increases when the flow resistance increases, controlling the amount of ink in the ink droplets ejected from the printhead with good precision becomes difficult. | {
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Progress in understanding complex biological systems depends on characterizing the underlying interactions of biomolecules, in particular proteins. While the DNA sequencing of an increasing number of organisms has identified their open reading frames (ORF), the possibilities to study the behaviour of the corresponding proteins in the living cell and to characterize multi-protein interactions in vivo and in vitro are limited. Most strategies that aim at realizing this objective are based on the construction of a fusion protein that, upon changes in the environment of the coupled protein, elicits a physical, physiological or chemical response. Examples include the yeast-two hybrid system, split-ubiquitin and green fluorescent protein (GFP) fusion proteins. However, all these techniques have various limitations or disadvantages.
German Patent Application No: 199 03 895 A (Kai Johnsson) describes an ELISA assay for the detection of O6-alkylguanine-DNA alkyltransferase (AGT). The mutagenic and carcinogenic effects of electrophiles such as N-methyl-N-nitrosourea are mainly due to the O6-alkylation of guanine in DNA. To protect themselves against DNA-alkylation, mammals and bacteria possess a protein, O6-alkylguanine-DNA alkyltransferases (AGT) which repairs these lesions [Pegg et al., 1995]. AGT transfers the alkyl group in a SN2 reaction to one of its own cysteines, resulting in an irreversibly alkylated enzyme. As overexpression of AGT in tumour cells enables them to acquire drug resistance, particularly to alkylating drugs such as procarbazine, dacarbazine, temozolomide and bis-2-chloroethyl-N-nitrosourea, inhibitors of AGT have been proposed for use as sensitisers in chemotherapy [Pegg et al., 1995]. DE 199 03 895 A discloses an assay for measuring levels of AGT which relies on the reaction between biotinylated O6-alkylguanine-derivatives and AGT which leads to biotinylation of the AGT. This in turn allows the separation of the AGT on a streptavidin coated plate and its detection, e.g. in an ELISA assay. The assay is suggested for monitoring the level of AGT in tumour tissue, adjusting treatment using AGT inhibitors as sensitisers in chemotherapy and for use in screening for AGT inhibitors.
Damoiseaux, Keppler and Johnsson (ChemBiochem., 4: 285-287, 2001) discloses the modified O6-alkylated guanine derivatives incorporated into oligodeoxyribonucleotides for use as of chemical probes for labelling AGT, again to facilitate detecting the levels of this enzyme in cancer cells to aid in research and in chemotherapy. Two types of variant AGT substrates and an assay for AGT in which it is labelled with biotin (the same as that described in DE 199 03 895 A) are disclosed. In addition, the use of these O6-alkylated derivatives in the directed evolution of the AGT is suggested. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
This invention relates to a process and apparatus for extracting hydrocarbons from oil shale by low temperature hydrogenating distillation.
2. Description of the Prior Art
Considerable crude oil reserves are stored in oil sands and oil shales. The extraction of crude oil from these reserves involves, amongst other things, high costs for the separation of the oil from the sand or shale. Attempts have therefore been made to make the technical processes required for this more favorable with regard to the course of the process, the material used and energy consumption.
A known process for extracting crude oil from oil sand or oil shale discloses subjecting this sand or shale to a low temperature hydrogenating distillation process in a reactor. At increased temperature and under pressure the initial feed material is affected by hydrogen and steam, which hydrogen and steam are at least partially recovered when the fluid distillation mixture is separated into gaseous and liquid products. Considerable amounts of energy are necessary for the entire duration of the process (U.S. Pat. No. 3,617,472). | {
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1. Field of the Invention
This invention pertains to shower heads and more particularly to shower heads designed to produce a wide, conical water spray pattern during low or high water pressure conditions.
2. Description of the Related Art
A wide variety of shower heads that provide pulsating or non-pulsating streams of water are known in the art. Most shower heads are also adjustable which provide a wide variety of flow patterns. Unfortunately, when the water pressure is relatively low (below 30 P.S.I.) the size of the spray pattern is destroyed.
Some shower heads design to create large spray patterns are relatively large structures comprised of large flat, circular structures with perforations or large bulbous structures with internal impellers or rotators that rotate or wobble when water flows through them. Unfortunately, many homeowners find large shower heads visibly distracting. | {
"pile_set_name": "USPTO Backgrounds"
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Aluminium may be produced by electrolytic reactions in electrolytic smelting pots, using the Hall-Héroult process. The process produces raw gas in the form of hot, particle-laden raw gas, which is cleaned in a gas cleaning unit before being discharged to the atmosphere. A duct system is usually used for channeling the hot, particle-laden raw gas from the smelting pots to the gas cleaning unit.
A typical gas cleaning unit may comprise a dry scrubber and a dust filter, e.g. a fabric filter that may be of the bag filter type. A consideration of such systems is that energy-consuming fans are often necessary in connection with raw gas treatment systems in order to actively draw the raw gas through the gas cleaning unit. Such is the case since the raw gas collecting ducts and the raw gas cleaning unit may introduce flow resistance in flue gas collection and cleaning systems.
Still another consideration is that raw gas treatment systems may require that the raw gas is cooled before entering the raw gas cleaning system. This requirement may be dictated by, for example, the temperature sensitivity of any downstream equipment, or by the temperature dependency of the cleaning efficiency of the gas cleaning unit. It is known to cool hot raw gas produced by aluminium smelting pots by mixing cool ambient air into the raw gas ducts upstream of a gas cleaning unit. Gas/air mixing is relatively simple, but for high gas temperatures the volume of ambient air required to provide adequate cooling becomes substantial, and so does the increase in cooled raw gas volume. Hence, as the volume of raw gas is increased, there must also be a corresponding increase in the size of the gas cleaning unit, the downstream fans that pull the gas through the gas cleaning unit, and the plant energy consumption. The energy consumption of an aluminium production plant may be substantial and it is desirable to find areas where the energy consumption may be lowered. | {
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It is desirable to convert analog signals to digital form, typically because a physical variable is in analog form and processing of it is more practical if it is in a digital form such as a stream of values representing samples of the analog signal. Analog to digital converters are well known and are frequently implemented with a first sample and-hold or track-and-hold stage that converts a continuously-variable analog signal to a sequence of stable analog levels followed by a second quantization stage that converts these stable analog signals to digital form.
Many architectures and electronic circuits are known for converting analog to digital signals, but practical limitations of the electronic devices used to implement these systems limit sampling rate, accuracy and consume power. It is known that these considerations need to be traded off, so that, for example, sampling rate can be increased at a cost in decreased resolution and increased power consumption.
It is known to combine a pair of analog to digital converters that operate in alternation, so that the effective sampling rate of the pair is twice that of the individual converters and this is often referred to as a “ping-pong” architecture. It is known to generalize this principle to use large numbers of subconverters operating in rotation to implement converters operating at very high speeds. These are sometimes known as interleaved, or N-path, architectures.
In interleaved architectures it is necessary that each sample-and-hold stage of each subconverter path be capable of sampling the input signal at the bandwidth of the overall desired system, rather than at the lower bandwidth for which a lower-speed converter would typically be designed. This difficulty reduces the practical speed advantage available by using interleaved architectures. It is also known that when signals to be sampled have spectra that are not “white” (where, as is now to those of skill in the art, “white” means that the signal does not have correlation between samples) the correlation between consecutive samples reduces the effective information rate of the ensemble of samplers. Still another problem exists in that sample-and-hold circuits are difficult to implement in some technologies, such as with bipolar transistors.
It is desired to have a means of combining multiple subconverters to form a conversion system with a higher effective sampling rate than the sampling rate of the subconverters that does not suffer from the sampling difficulties of conventional interleaved systems. | {
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Acne is a common skin disease, typically affecting 60 percent of the population at any time. Most of the acne is seen in adolescents; however there can be a second recurrence of acne in people in their late twenties and early thirties, mostly in women.
Acne is a systemic inflammatory disease, and may be exacerbated in puberty due to the release of hormones, as well as a pro-inflammatory diet. Dermatologists classify the primary event in acne as the formation of the microcomedo, i.e., the clogging of a follicle with what is believed to be non-inflamed lesions caused by retention hyperkeratosis. However, the hyperkeratinization of the follicle is not the primary event, but the result of the release of pro-inflammatory cytokines (such as interleukin-1) in the follicular wall, resulting in increased cohesion of the cells and a clogged pore. There also may be activation of the pro-inflammatory transcription factor NFκB secondary to oxidative stress in the follicle. In addition, fatty acids within the follicle may be pro-inflammatory and may mimic active messengers similar to the pro-inflammatory platelet-activating factor.
Another causative event is the stretching of the follicular wall, caused by the impaction of exfoliated keratinocytes. This stretching can release phospholipids from the cell walls, which are broken down into pro-inflammatory fatty acid messengers. Arachidonic acid also plays a part in the inflammation as well.
Dermatologists typically use a grading system to categorize the various stages of the acne lesion. Grade One, the microcomedone, can appear as whiteheads or blackheads. Grade Two is a papule, i.e., a small pink inflamed bump. Grade Three is a pustule lesion with more visible inflammation than papule. Grade Four is a nodule or large painful solid lesion that extends deep into the skin. Grade Five is an inflamed lesion, very large and painful. It should be noted that as the follicle becomes impacted, it is often secondarily infected with propionibacteria. | {
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Organic protective coatings represent the most versatile and economical technology available for protection of metals against atmospheric corrosion. Corrosion inhibitive primer coatings are solid composites, comprising finely divided, usually multi-component, inorganic pigment phases dispersed in continuous organic polymer phases, which provide strong adherence to the protected metal substrates.
Although the physical characteristics of primers are reinforced by the dispersed inorganic pigment phases, they nevertheless remain permeable to O.sub.2, H.sub.2 O and air-borne pollutants. As a consequence, thin organic coatings do not prevent atmospheric corrosion of metals, unless they are specifically formulated with active corrosion inhibitor constituents, included in the pigment phase.
Contrary to appearances, a metal substrate protective primer, in equilibrium with its environment is a dynamic medium which accommodates several concurrently occurring physical and chemical processes, in which water, always present due to the resin phase's permeability, plays a critical role.
Water content affects the physical integrity of organic coatings in several ways. Most importantly, in this specific sense, it dissolves all soluble components (inclusive of pigments) to saturation concentrations and supports in situ diffusional transport processes of dissolved constituents. Water accumulates preferentially at metal-coating interfaces, causing loss of interfacial adhesion and more specifically supporting the electrochemical processes of metal corrosion. Paradoxically, in actively pigmented organic coatings water supports the inhibition of metal substrates' atmospheric corrosion, as well, by in situ solubilization of active pigments. Corrosion inhibitor pigment constituents of protective primers can be regarded as built in reservoirs of corrosion inhibitive species.
Commercially available chemically active corrosion inhibitor pigments used for Fe, Al, or Cu protection, belong exclusively to only a few classes of inorganic compounds, such as chromates, phosphates or polyphophates, molybdates, borates, silicates and phosphites of Zn, Ca, Sr, Ba, Al, Mg, Pb, Cr, Fe, or various combinations of these anionic and cationic species. Chromates and some of the latter cationic species, particularly Ba, Pb and Cr are known to be toxic. Transition metal derivatives of hydrogen cyanamide, particularly ZnNCN are also known for pigment grade application, limited, however, to special mirror backing coatings intended for Ag protection.
Generally, the active inhibitor species are the anionic constituents. Cations present, however, determine important physical properties of pigments such as solubility. Chromates, and specifically SrCrO.sub.4, are the standard of the industry, being the most versatile, applicable on all metal substrates such as Fe and specifically Al alloys and being highly effective, although toxic, pigment grade corrosion inhibitors. It is the redox activity of chromate species, accountable for their inhibitive efficiency which provides interference with corrosion processes in both, anodic and cathodic environments.
In contrast with chromates, all other active corrosion inhibitive pigments, more specifically, the anionic constituents of phosphates, molybdates, silicates, borates, phosphites and cyanamides are "redox inactive" under usual metal corrosion conditions. The consequences of "redox inactive" inhibitive mechanisms are significant. It can be generally stated that non-chromate based corrosion inhibitor pigments are less effective and qualitatively inferior, but non-toxic alternatives of chromates. As a consequence, for aircraft coatings used for aluminum protection and for coil coatings, where top corrosion inhibitive performances are required, SrCrO.sub.4 has no equally effective non-chromate alternatives. Development of effective and non-toxic alternative to chromates remains one of the major objectives of contemporary corrosion inhibitor chemistry.
As is well known, there is a large arsenal of organic corrosion inhibitors employed in industrial practice, limited, however, to gas phase and liquid medium applications. Logically, it would be expected, that the same arsenal would be appropriate for paint and coating applications as well, which, paradoxically, is not the case. The apparent contradiction is understandable by considering that in paint and coatings related applications, in addition to corrosion inhibitive efficiency, "pigment grade" qualities are required, as well.
Besides general quality requirements, "pigment grade" quality is defined by an additional, quite limiting set of parameters. Most important of these are non-volatility, solid consistency, specific gravity of 2.5-5.0, effective but limited solubility in water, virtual insolubility in organic solvents, absence of deleterious effects on coating's mechanical properties and, notably, no interference with curing processes. It will be apparent in this sense, that coatings related applications are not compatible with physical properties such as volatility, excessive solubility in water or organic media, which are however, critical requirements of gas phase or liquid medium related applications of organic corrosion inhibitors, respectively.
Various organic compounds with --SH functionality, such as thiols, derivatives of dithiocarbonic, dithiocarbamic and dithiophosphoric acids, are known to exhibit corrosion inhibitive activity. For example, diverse thio-organic compounds, such as N-containing heterocyclic mercapto derivatives, i.e, 2-mercaptobenzothiazole (MBT), are well known corrosion inhibitors employed practically exclusively in dissolved form, as a functional component of aqueous, polar organic or hydrocarbon based liquid systems. Typical applications of organic corrosion inhibitors in water, polar organic solvents or hydrocarbons include heat exchangers, anti-freeze systems, steam condensers or hydraulic oils, metal cutting liquids, and lubricants. Water soluble related Na or K salts (for example Na-MBT) or "thio" compounds in their more hydrocarbon soluble acidic form (such as MBT) are preferred in the former or the latter applications, respectively.
U.S. Pat. No. 4,329,381 shows the use of toxic Pb and Zn salts of selected five or six membered nitrogen-containing heterocyclic mercapto derivatives, notably Zn(MBT).sub.2, as corrosion inhibitor components of organic coatings, more specifically by incorporating such compounds as finely divided, distinct solid component phases into paint or coating systems, more specifically for protection of Fe.
A significant limitation of this concept is that technical grade Zn(MBT).sub.2, when produced according to the procedures described in the '381 patent contains high amounts of unreacted MBT. Thus, when formulated as a finely divided, distinct low specific gravity component in paint systems, these ingredients interfere with and inhibit the curing process of oil alkyd resin based coatings. This is a significant limitation, because it is estimated that about 60% of all primers intended for metal protection are oil alkyd resin based.
Two known procedures for synthesis of MBT derivatives and specifically of Zn(MBT).sub.2 are described in the '381 patent:
A. Conversion into Zn(MBT).sub.2 of aqueous mixed suspension containing ZnO (or alternatively, basic zinc carbonate) and MBT performed with extensive agitation and heating at approximately 100.degree. C., in the presence of catalytic amounts of acetic acid, according to: EQU xZnO+2xMBT.fwdarw.(1-x)Zn(MBT).sub.2 +2xMBT+xZnO+(1-x)H.sub.2 O(1)
B. By double decomposition or precipitation, using aqueous solutions of NaMBT and zinc salts according to: EQU 2NaMBT+Zn(X).sub.2 +H.sub.2 O.fwdarw.(1-x)Zn(MBT).sub.2 +2xMBT+xZn(OH).sub.2 +2NaX (2)
where x>0, X=Cl(-), NO.sub.3 (-), etc.
As will be demonstrated in Comparative Example 1, neither procedure is suitable as disclosed, because of inability to yield reasonably pure Zn(MBT).sub.2 necessary for paint applications, but rather a mixture containing quite high amounts of unreacted MBT and ZnO is produced. Notably, this is true as to all commercially available technical grade Zn(MBT).sub.2 of diverse origin. For example, the commercial product offered by the Bayer Corporation under the trade name Vulkacit ZM contains in excess of 13% of free MBT.
It is important to observe that unreacted MBT content in technical grade Zn(MBT).sub.2 has significant adverse consequences with respect to suitability of such products in paint-coating applications. Specifically, if added as a finely divided distinct solid component into paint systems, technical grade Zn(MBT).sub.2 inhibits the curing process of oil alkyd resin based coatings. Conversely, as it was also discovered that Zn(MBT).sub.2 purified by solvent extraction does not display any cure inhibitive activity even at considerably higher concentrations in medium oil alkyds. (See Comparative Example 1).
As for the chemical mechanism which causes the curing inhibition, free MBT reacting with Co(II) or Pb(II) species (the active constituents of driers typically used in oil alkyd paint formulations), is hypothesized. Consequently, with respect to interference with curing processes, similar behavior should be considered typical for all thio-organic compound families with --SH functional groups, as well as for related zinc salts of technical grade.
Quantitative determination of unreacted MBT content of Zn(MBT).sub.2 can be conveniently carried out gravimetrically, by repeated extraction in acetone, or it can be estimated by IR spectroscopy. Intense absorption bands situated at 1496 and 1425 cm(-1) of the related spectrum, are characteristic for MBT. (See Comparative Example 1)
An additional limitation of the concept of the '381 patent relates to the fact that the specific gravity of Zn(MBT).sub.2 (1.5-1.7), and generally that of other mercapto derivatives, is quite low in comparison with such values typical for other components of a paint system's dispersed inorganic phase, which range from 2.5 to 5.0, or with density values of cured coatings of about 2.0. Notably, also, the zinc and lead salts of mercapto derivatives form ordinary mixtures with other components of the dispersed pigment phase.
As is known, shelf-stable paint systems' dispersed solid phases, usually multi-component ordinary mixtures of the constituents of the same, tend to segregate by "flooding", if they contain components with appreciably different specific gravities. Due to convective processes related to solvent evaporation, flooding occurs during the curing of freshly applied coatings, resulting in predominant accumulation, at the coating-air interface, of the dispersed solid phase's low specific gravity components and ultimately, in an anisotropic composition, and consequently, a reduced protective capacity of the resultant coatings. These phenomena are well known with respect to paint applications colored by organic pigments.
Since low specific gravity values are typical for zinc salts formed by relatively "bulky" organic moieties, such as Zn(MBT).sub.2, segregation by flooding has relevance to the application of such compounds as paint additives and constitutes a considerable shortcoming thereof.
There are essentially three different structural states in which two (or more) microcrystalline or amorphous component phases of distinctively different chemical composition can co-exist as constituents of multi-phase and finely divided solid systems: ordinary physical mixtures, micro-composites and solid solutions.
Solid solutions, although formed spontaneously, are not commonly found in multi-phased solid systems. In some cases, however, distinct combinations of three or more anionic and cationic constituents, which ordinarily form two or more solid phases of distinct chemical composition, in special conditions form unified solid phases of complex chemical composition. Such unified phases are characterized by uniform distribution at molecular level of all constituent ionic species.
Ordinary mixtures of finely divided (and normally polydispersed) solid phases of different chemical composition are constituted of distinct and separable microparticles of the distinct component phases, mixed and uniformly distributed in the system. Ordinary mixtures can be prepared by simple mechanical procedures. However, they are often formed spontaneously in chemical processes as well, such as during concurrent or subsequent formation by precipitation of two or more solid phases in aqueous systems.
Conversely, micro-composite (multi-phase and finely divided) solid systems are constituted of microparticles, containing distinctly identifiable, but physically inseparable component phases of different chemical composition which form common interfaces and are held together by chemical forces. In some cases composite microparticles possess a structural configuration of a coating-core type, often formed in some heterogenous chemical processes, such as described in my U.S. Pat. No. 5,176,894, wherein a finely divided suspension of an essentially insoluble solid reactant is reacted with a dissolved component reactant of a liquid phase and consequently is converted into a finely divided suspension of a solid reaction product, which is insoluble in the reaction medium. During the course of the reaction the suspended solid phase consists of composite micro-particles of a coating-core configuration, in which both solid component phases, i.e., the reaction product coating and the reactant core are simultaneously present, separated and bound together by an interface which in many cases is of a generally spherical shape, but also may consist of other configurations such as lamina, etc. This mechanism, obviously, implies the reagent species' continuous diffusion through the coating phase toward the reactant core and generally, the reaction is diffusionally impeded. Thus, by preventing completion of the reaction, the solid product's micro-composite structure is preserved.
Notably, there are also numerous examples known to the art regarding preparation of microcomposite multi-phase solid systems by, in comparison, a quite different process and mechanism. Known as "particle encapsulation" procedures, widely used in the pigment manufacturing industry, are the formation by precipitation of chemically inert coatings of diverse chemical composition on the surfaces of finely divided solids in aqueous suspension.
The microcomposite structures of multi-phase solids prepared in aqueous processes, commonly are preserved throughout typical pigment manufacturing operations, which include filtration, dehydration and grinding. Pertinent experimental data are presented in Comparative Examples 2.1 and 2.2.
Another significant limitation of the concept of patent '894 is, that zinc salts of thio-compounds, such as Zn(MBT).sub.2, in ordinary mixtures with zinc phosphate, the inhibitor pigment specified in the patent, do not form synergistic systems and do not display synergistically enhanced corrosion inhibition performance.
In view of all of these considerations, a need has existed for improved corrosion inhibitor systems. | {
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The present invention relates to the fabrication of integrated circuits. More particularly, the invention provides a technique, including a method and apparatus, for modifying the profile of high-aspect-ratio trenches on a substrate to fill those trenches with void-free dielectric material.
Semiconductor device geometries continue to decrease in size, providing more devices per fabricated wafer and faster devices. Currently, some devices are being fabricated with less than 0.25 xcexcm spacing between features; in some cases there is as little as 0.18 xcexcm spacing between device features. The space between features often takes the form of a trench.
If the height of the features remains constant, reducing the spacing between features increases the aspect ratio of trenches between the features. The aspect ratio of a trench is the ratio of the height of a trench to the width of a trench. For example, a trench that is 2 xcexcm deep and has a 1 xcexcm gap has an aspect ratio of 2:1. Two examples of such trenches that frequently have high aspect ratios are isolation trenches and the trenches formed by adjacent conductive traces on a substrate. Isolation trenches are formed in a substrate between features, such as transistors, and conductive traces are typically formed by patterning a layer of metal or other conductor.
Material, such as doped or undoped silicon oxide glass, is often deposited in the trenches. The deposited material may serve several purposes, including protecting the substrate or conductive lines from physical or chemical damage, electrically insulating one side of the trench from the other, and providing a surface to build subsequent features on. One way to deposit trench-filling material is by chemical vapor deposition (CVD), where gases react or are decomposed to form a film, or layer, on the substrate.
FIGS. 1(a) through 1(c) illustrate that a void may form as a trench with a narrow gap is filled. In conventional CVD processes the gap may become pinched off as material accumulates on the upper edges of the trench as the trench fills. This forms an overhang 4 that may eventually merge, leaving behind a void 5 in the deposited material. Such a void may cause yield or reliability problems.
One method for keeping a gap open so that a trench may be filled is to use a plasma process that sputter etches some of the deposited material away as a layer is being formed. Using a plasma etch during deposition keeps gaps open because the rate of plasma sputter etching is dependant on the surface angle of the material being etched, and is higher at the corners of the trenches.
FIG. 2 shows that the rate of etching 6 in a plasma sputtering system varies as the surface angle, or angle from the horizontal plane of the substrate. In the example shown in FIG. 2, the maximum etching rate 7 occurs at 45 degrees to the horizontal, which represents the etching rate at a corner, or edge, of a trench. FIG. 2 shows that the etching rate at a corner of a trench is about 4 times greater than at a horizontal surface (also known as the xe2x80x9cfieldxe2x80x9d) for the conditions represented in FIG. 2. The difference between the angular etching rate and the deposition rate 8 in a deposition/etch process allows formation of a facet 9, rather than an overhang, at the edge of a trench, as shown in FIG. 3. It is generally desired, after an initial thin layer of material has been deposited, that the etching rate equal the deposition rate at the trench corners, resulting in no net deposition or etching in this region. Balancing the rate of deposition with the rate of etching should keep the trench open without exposing the underlying corner.
Simply filling a trench by plasma etching during a deposition process appears to be an attractive way to fill a narrow, high-aspect ratio trench in a void-free manner; however, the solution is not that simple. First, etching a layer as it is being deposited reduces the net deposition rate, thus increasing process time and associated cost. Second, the difference between keeping the gaps open and etching into the material forming the edge of the trench can be slight. Etching into the material forming the edge of the trench is undesirable because it erodes the edge, which can affect device performance and because it can contaminate the processing chamber and substrate. Sealing, or lining, the edge of the narrowly spaced gaps so that the trench edge won""t be exposed by the plasma etching is difficult and tricky. Only a very thin lining layer can be deposited before the gap starts pinching shut. A thin lining layer does not provide much margin for error when etching to keep the trench open. It is especially difficult to uniformly process large wafers because it is generally more difficult to maintain the required process control over a larger area.
It is typical for a process to have some variation, or xe2x80x9crun-outxe2x80x9d, across the surface of the wafer, and it is challenging to fill narrow trenches in a gap-free manner as the size of typical wafers continues to increase. The combined effects of shrinking device geometries and increasing wafer size makes it even more important to understand the gap-filling process so that additional process controls may be applied. Conventional deposition methods have not addressed the subtle nature of some parameters that affect the gap-filling process. Thus, it is desirable to provide a deposition process with greater control over the process parameters to fill narrow gaps in an efficient, void-free manner.
The present invention recognizes that it is possible to modify the profile of a trench during a deposition process to fill that trench in a gap fill manner. The trench profile modification can lower the aspect ratio of the trench, thus making it easier to efficiently fill the trench in a gap-free manner. The trench may be etched into a silicon substrate, such as the type of trench used for shallow-trench isolation (STI), may be formed by a patterned metallization layer, or may be another type of trench.
The trench profile is modified during a deposition process in a high-density plasma CVD (HDP-CVD) system. The HDP-CVD system was modified in various ways to provide additional control over the deposition process, particularly with respect to how the plasma heats a substrate. It was determined that the profile of a trench may be modified by the heating the backside of the substrate, by controlling the thermal coupling between the substrate and a supporting structure, by altering the configuration of the plasma, or by a combination of these methods. These methods and combinations of methods provides degrees of process control that allow the efficient deposition of void-free material in narrow gaps.
In a specific embodiment, the backside of a substrate is heated during the deposition process while the front side of the substrate is heated by the plasma formed in the HDP-CVD system chamber. Heating the backside of the substrate changes the temperature profile of the wafer, resulting in a hotter wafer surface, which alters the deposition characteristics. In another embodiment, the substrate is not chucked to the wafer support structure. By not chucking the substrate, less heat is transferred from the surface of the substrate to the wafer support structure, and the surface of the wafer, which is heated by the plasma, becomes hotter than it would if the substrate were chucked. Thus, not chucking the substrate also alters the deposition characteristics.
In another embodiment, the amount of radio frequency (RF) power provided to a top coil relative to the amount of RF power provided to a side coil is adjusted to control the plasma characteristics. The surface of the substrate is heated by the plasma, so controlling the plasma characteristics may also be used to control the surface temperature of the substrate and hence the deposition characteristics.
These and other embodiments of the present invention, as well as its advantages and features are described in more detail in conjunction with the text below and attached figures. | {
"pile_set_name": "USPTO Backgrounds"
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This application claims the benefit of U.S. Provisional Application No. 60/174,961, filed on Jan. 7, 2000. The present invention relates generally to customer communication services. More particularly, the invention is a system and method for managing and integrating multimedia customer and customer-client interactions.
Customer communication services have traditionally involved using call center technology to allow customers to contact a service agent via a telephone or for allowing agents, such as telemarketers, to contact customers. A call center is a central place where customer and other telephone calls are handled by a service organization, usually with some amount of computer automation. Typically, a call center has the ability to handle a considerable volume of calls at the same time, to screen calls and forward them to someone qualified to handle them, and to log calls. Call centers are used by mail-order catalog organizations, telemarketing companies, computer product help desks, and any large organization that uses multiple telephones to sell or service products and services.
Some companies have a network of geographically distributed call centers for serving customer's needs. Such distributed call centers often provide redundancy and decentralization.
In a call center, agents handle telephone communications with callers. Each agent is typically assigned to a telephone connected to a central switch, which is in turn connected to a public switched telephone network (PSTN). The central switch may be one of several types such as an telephony switching apparatus (TSA), private branch exchange (PBX), or PSTN. If the call center consists of just a central switch and the telephones connected to it, the routing capabilities are limited. There may also be limits in the range of computer processes that may be performed.
To achieve greater computerization of call centers, advances have been made in the use of computers to manage telephone calls, known as computer telephone integration (CTI). CTI is used to describe the computerized services of call centers such as those that direct a phone call to the right department at a business that is being called. It is also sometimes used to describe the ability to use a personal computer to initiate and manage phone calls. CTI applications provide the ability to do one or more of the following: Authenticate callers. Using one of several standard methods, the telephone number of the caller can be screened against a database, Recognize a voice, either for authentication or for system commands, such as digit recognition, Determine how to process a call (for example, by forwarding it to the appropriate person or department) using live, recorded voice, or touch-tone entered input, Provide interactive voice response (IVR) to callers, Match the number of a caller with a customer record and display it for reference when talking to the caller, Manage voice or video conferences, Collect and display pending live calls or messages that have been left by callers, Receive fax messages and route them to appropriate fax machines, Pre-dial callers for outbound calling such as telemarketing, Initiate a smart agent application to provide help with the caller's request based on call input.
When calls are received at a CTI call center, they are placed into a queue until an agent is available to take the call. In the CTI call center, typically an agent using a telephone station connected to the central switch also has access to a computer terminal. The central switch may consist of hardware and software that control a call from the time it arrives until the service agent answers it. The central switch provides the interface with the customer (allowing the customer to hear messages and music, etc.) and may also perform other functions such as gathering information about the call and the customer before routing the call to an available service agent. The Telephony Switching Apparatus (TSA) software routes the call to a knowledgeable and available service agent using knowledge obtained about the caller and the caller's needs.
In addition to using the medium of voice, other media are used to attempt to efficiently handle the large volume of customer contacts processed by a call center and to improve caller customer service. Other media include chat, voice mail messages, electronic mail, facsimile messages and video messages. The agent's computer terminal may be used to access databases of stored data and information about the call and caller may also be displayed on the computer screen for the agent. The computer terminal may be interconnected by a network to a server, which contains the CTI software.
However, many of these other media are not integrated into the call center processing. There is often no way to track the performance of the call center for some or all of the media. Usually, the call center system does not capture and process these different communication media seamlessly and simultaneously. The result is that the service agent does not have an integrated communication interface with the caller which can result in a slower and less than satisfactory processing of the call. | {
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The present invention refers to a method of sterilizing a package material. More precisely the invention refers to a method of sterilizing a package material having a plastic surface by means of hydrogen peroxide in gaseous phase being supplied to the previously heated plastic surface.
Sterile containers which are ready to be filled can be obtained in various ways. One method of sterilization implies that the plastic containers are sealed directly in connection with the manufacturing procedure, e.g. when blow moulded. Due to the collapse of the container at a subsequent lowering of the temperature the sealing in this case results in considerable problems. The container must therefore be stored at an elevated temperature since the volume of air enclosed in the container will decrease if the temperature is decreased. Such a storage is both cumbersome and costly. In order to avoid this, among other materials hydrogen peroxide is nowadays utilized in a liquid or gaseous phase, the inside of the containers then being sterilized.
Hydrogen peroxide is a very potent but not especially stable oxidant, and an advantage is that only plain water is formed as by-product. However, the half-life of hydrogen peroxide is very long, and the sterilizing agent has thus to be removed after it has been allowed to exert its effect.
Hydrogen peroxide is supposed to exert its antimicrobial activity through its powerful oxidizing effect by acting on components in the cytoplasmic membrane of the microorganisms. In the sterilizing procedure hydrogen peroxide is used as a water solution which is sprayed into a container. When the container is subsequently heated the hydrogen peroxide is gasified and can be ventilated away after having exerted its effect.
According to an alternative sterilizing procedure a container is in a first step subjected to hydrogen peroxide in gaseous phase, which is allowed to condensate on the inside of the container. By this procedure a homogeneous coating of hydrogen peroxide is obtained, which completely covers the package material. In a subsequent step the condensated gas is again gasified and is finally ventilated away. By this procedure an acceptable death rate of micro-organisms for commercial sterilization can be achieved.
When for example plastic containers are sterilized these are in practice coated with a commercial standard solution, called xe2x80x9cOxonia Aktivxe2x80x9d, which among other things contains hydrogen peroxide and peracetic acid. The solution is allowed to act for some minutes, and the containers are then rinsed with clean sterile water. Such a procedure is both complicated and time consuming.
A further problem is that with certain plastics in the package material, above all polyester, residues of hydrogen peroxide are obtained which are adsorbed on the inside of the container as a result of spraying, coating or condensation. They can afterwards have a negative influence on the filling material, for example by changing the colour. The authorities have established limit values which must not be exceeded for residues of hydrogen peroxide.
It is rather unusual to treat such a package material as a polyester aseptically since this type of material mostly is used for soft drinks and the like. However, there exists a great interest from the market for an aseptic bottle of polyethylene terephtalate (PET).
In order to minimize the risk of residual product formation the hydrogen peroxide can be ventilated away, e.g. at the elevated temperature or by sterile air being blown into the container. Such a procedure is costly and it would thus be desirable if shorter ventilation times could be used, which would result in a lower cost per container.
The purpose of the invention is to eliminate or reduce the drawbacks mentioned above which arise during a sterilization by means of hydrogen peroxide according to the state of the art.
In order to achieve this purpose the method according to the invention has obtained the characterizing features of claim 1.
A sterilizing process with a condensation of hydrogen peroxide comprises four phases of different time intervals: a heating phase, a gassing phase, a holding phase, and a ventilation phase.
During the heating phase the container is heated to a suitable temperature. The heating phase is not necessary. However, it reduces the amount of condensate which later on has to be ventilated away.
During the gassing phase gaseous hydrogen peroxide is injected into the previously heated container and over the surface which is to be exposed to the treatment, onto which the gas condensates, and a condensate in the form of droplets is formed. The gas used is a mixture of air and a gasified solution of hydrogen peroxide. The solution of hydrogen peroxide is supplied as a commercial grade which consists of about 65% water and about 35% hydrogen peroxide. However, other concentrations can of course be used in dependence of other parameters.
During the holding phase the condensate is allowed to exhibit its effect, and during the ventilation phase the container is ventilated, the condensate again being transformed into gaseous phase and removed from the container. In this connection hot air is used which has been prefiltered and sterilized by means of filtration.
Experiments were performed with the purpose of achieving an equally effective sterilization as that which allows the hydrogen peroxide used to exert its effect in the form of a condensated gas. In these experiments the hydrogen peroxide was according to the invention allowed to remain in the gaseous phase during the entire sterilization procedure.
In comparison with the sterilization by means of condensation described above the method according to the invention implies briefly that the containers are sterilized with gasified hydrogen peroxide, the containers first being heated to a temperature which is higher than the dew point of the gas used. The containers are then blown to dryness with hot sterile air.
During the sterilization procedure the containers are thus for a certain period of time exposed to gaseous hydrogen peroxide of a specific temperature, dew point and flow rate. Apart from the hydrogen peroxide concentration these parameters are important in order to achieve an effective killing. In this connection the dew point is the temperature the gaseous hydrogen peroxide must be cooled to in order to obtain a condensation, a water solution of hydrogen peroxide being separated. This temperature is dependent on the hydrogen peroxide content in the gas. The dew point is adjusted to be used in an existing sterilizing equipment.
Preliminary experiments have shown that the amount of residual hydrogen peroxide per unit area varied after contact with different types of package material. Certain problems were obtained with polyester as a package material, and thus the experiments were concentrated on such a material by using bottles of polyethylene terephftalate. However, other types of containers which are ready to be filled were also studied. | {
"pile_set_name": "USPTO Backgrounds"
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1. Technical Field
This invention relates to the field of voice response systems and more particularly to a method and system for voice data entry recognition in a voice response system.
2. Description of the Related Art
In data information systems in which forms are employed with which a user can supply data to the system, often a field, or series of fields can be completed by the user. In such data information systems, users can supply data for each field in the form. However, data fields can be restricted with regard to the data which can be supplied therein. For instance, in a data information system for collecting user contact information, a form can restrict data supplied in the city and state fields to those cities or states which are available (have associated data) in the data information system. As an example, while Miami, Fla. might be an available city and state pair in the system, the data information system might not have any information about the city and state pair Sunny Ga. making Sunny Ga. unavailable in the system.
In visually interactive data information systems employing visual interfaces, data to be supplied in a field in a form can be restricted through the use of a corresponding list box. In a list box, users can be presented with a predefined list of data entries acceptable for input in a corresponding field. Still, the use of a list box in an audibly interactive data information system employing an audio user interface can prove tedious at best. First, in an audio user interface, for each list box corresponding to a field in a form, the audio user interface must audibly playback the acceptable data entries in the list box until the user selects one of the acceptable data entries. As an alternative, the user can memorize each available data entry in the list box prior to audibly supplying an available data entry.
Second, unlike the case of a visual user interface, in an audio user interface, the problem of data entry availability can be compounded with the problem of speech recognition. In particular, in the case of a visual user interface, the user can select an available data entry with a mouse-click or by typing the acceptable data entry. In either case, the user-supplied data entry is unmistakable. In contrast, in the case of an audio user interface, in addition to surmounting the data availability process, the user-supplied data must surmount recognition problems associated with the speech recognition process. More specifically, anything that is to be audibly supplied to a field in a form through an audio user interface not only must be considered an available entry from the perspective of the data information system, but also must be considered a speech recognizable entry from the perspective of the speech recognition engine.
For example, in a voice response system, each word supplied as a voice response must exist in a speech recognition grammar in order to successfully undergo a speech-to-text conversion process. If a user utters a word not contained in the speech recognition grammar, an Out of Grammar (hereinafter xe2x80x9cOOGxe2x80x9d) condition can arise. Typically, a voice response system can respond to an OOG condition by xe2x80x9cthrowingxe2x80x9d an OOG exception. When an OOG exception is thrown, a voice response system can only inform the user that the voice response provided to the voice response system was not understood (because it was not located in the speech recognition grammar).
The circumstance in which a user interacts with a voice response system for providing information regarding particular cities is an example of this problem. When prompted by the voice response system to provide the name of a city for which the voice response system can provide information, a user can utter, xe2x80x9cSunnyxe2x80x9d as in Sunny Ga. Preferably, if the voice response system does not contain information Sunny Ga. the user should be notified, xe2x80x9cThere is no information on Sunny, Ga.xe2x80x9d. However, if Georgia is not included in the speech recognition grammar, when the user utters Sunny Ga., the voice response system will throw an OOG exception and the data information system will respond with, xe2x80x9cI did not understand what you said.xe2x80x9d Consequently, the voice response system cannot indicate to the user that Sunny Ga. is not an available city/state pair in the data store of the voice response system because the voice response system never successfully speech recognized the user voice input xe2x80x9cSunny Ga.xe2x80x9d in the first place. Thus, there exists a need for a voice response system in which words not contained in the data stores of the voice response system are nonetheless recognized by the voice response system so that the voice response system can report the same to the user.
The present invention is a voice response system in which words not contained in the data stores of the voice response system are nonetheless recognized by the voice response system so that the voice response system can report xe2x80x9cNo information on . . .xe2x80x9d rather than reporting an OOG exception. The present invention solves the problem of the OOG condition by overloading the speech recognition grammar with word data entries which may or may not exist in the voice response system data stores. In consequence, voice responses which a user might speak are at least recognizable and xe2x80x9cactionablexe2x80x9d by the voice response system, even though the voice response may not be an available response in the data store. In the above-described example, a user can provide the voice response, xe2x80x9cSunny Ga.xe2x80x9d and receive in return from the voice response system, xe2x80x9cThere is no information on Sunny Ga.xe2x80x9d In contrast, a user can provide the voice response, xe2x80x9cIskabibblexe2x80x9d which correctly can cause an OOG condition. In response, the user can receive from the voice response system, xe2x80x9cI did not understand what you saidxe2x80x9d. Hence, the present invention alleviates the OOG condition which would otherwise create a bad usability problem.
A method for voice data entry availability in a voice response system can include establishing a data set of words relating to a data information system; including the data set of words in a speech grammar for use with a speech recognition engine; and including a subset of the data set in a data store, wherein the subset has words used by the data information system, and the subset does not have words in the data set which are not used by the data information system. Subsequently, speech queries can be received which specify data. The speech queries can be received through an audio user interface to the data information system. Speech-to-text conversion can be performed on the speech queries using the speech recognition engine.
If the specified data is in the data set and if the specified data also is in the subset, the speech queries can be processed with the specified data. However, if the specified data is in the data set, but the specified data is not in the subset, the specified data is reported not to be in the subset. Finally, if the specified data is not in the data set, it is reported that the specified data cannot be speech-to-text converted. Furthermore, the speech query is not processed.
In the preferred embodiment, the step of reporting that the specified data cannot be speech-to-text converted can include throwing an Out-Of-Grammar (OOG) exception. Additionally, the step of receiving speech queries through an audio user interface to the data information system can include receiving speech queries in the voice response system telephonically. Specifically, the speech queries can originate through a telephone handset. Subsequently, the speech queries can be transmitted no through a telephone data network and received in the voice response system through a telephone data network interface in the voice response system. Finally, the speech queries can be communicated from the telephone data network interface to the audio user interface.
Alternatively, the speech queries can originate in a kiosk, through a personal digital assistant, a personal computer, or any other suitable platform for providing audio input to a computer speech recognition system. Notably, the audio user interface can be a Voice Browser to a Web-enabled data information system, wherein the Voice Browser enables voice operation of the Web-enabled data information system.
A method for voice data entry availability in a voice response system can also include receiving speech input specifying data in an audio user interface to a data information system for processing data in a data store. The speech input can be received through an audio user interface to the data information system. Subsequently, speech-to-text conversion of the speech input can be performed using a speech recognition engine with reference to a corresponding speech grammar. In particular, the speech grammar can contain a data set of words relating to the data information system. Notably, the data store can contain a subset of the data set, the subset having words which can be processed by the data information system, the subset not having words which cannot be processed by the data information system.
If the specified data is included in the speech grammar and if the specified data is in the data store, the speech data in the speech query can be processed. However, if the specified data is not in the data store, it can be reported that the specified data cannot be processed. Finally, if the specified data is not included in the speech grammar, an Out-Of-Grammar (OOG) condition can be reported. Additionally, the speech data in the speech query is not processed.
In the preferred embodiment, the step of reporting an OOG condition can include throwing an OOG exception. Additionally, the step of receiving speech input in an audio user interface to the data information system can include receiving speech input in the voice response system telephonically. Specifically, the speech input can originate through a telephone handset. Subsequently, the speech input can be transmitted through a telephone data network and the speech input can be received in the voice response system through a telephone data network interface in the voice response system. Finally, the speech input can be communicated from the telephone data network interface to the audio user interface. Notably, the audio user interface can be a Voice Browser to a Web-enabled data information system, the Voice Browser enabling voice operation of the Web-enabled data information system. | {
"pile_set_name": "USPTO Backgrounds"
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The invention relates in general to hypodermic syringes for medical injection and more particularly to syringes which are limited to a single use, thereby preventing the spread of disease by drug offenders, and others, through the sharing of syringes. The invention relates also to devices for the protection of medical workers, and others, from accidental syringe needle scratches. | {
"pile_set_name": "USPTO Backgrounds"
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1. Technical Field
The present invention relates to a control apparatus that controls pump torque so as to raise engine speed from low engine speed to target engine speed quickly in a construction machine such as an excavator.
2. Description of the Related Art
A related art of the present invention is explained with reference to an excavator as an example.
The engine speed during no load of an engine mounted on the excavator is usually set according to an operation applied to an engine speed setting device called acceleration potentiometer, selection of a work mode, and the like. When there are a plurality of determination elements, a lower value is selected. By use of the set engine speed as a target engine speed, a fuel injection quantity in the engine is controlled.
On the other hand, in an excavator with an auto-deceleration function, there is performed an auto-deceleration control for reducing engine speed to set engine speed, i.e., deceleration engine speed, when a predetermined deceleration condition (e.g., a fixed time elapses after lever operation is stopped) is met. When the deceleration condition is not met, for example, when a lever operation is performed, performed is a return-from-deceleration control for raising the engine speed to target engine speed.
In this case, if an actuator is operated during a return from deceleration, the engine speed is not smoothly raised because of a pump load and the engine speed is delayed in reaching the target engine speed. As a solution to this problem, Japanese Patent Application Laid-open No. H5-312082 discloses a technique for reducing an engine load and quickening a rise of engine speed by minimizing pump torque, which is absorption torque of a hydraulic pump, during the start of an engine; however, minimizing the pump torque in this way makes it impossible to substantially perform an actuator operation, i.e., excavator work until the engine speed completely rises. This problem can occur not only during the return from deceleration but also during raising of the engine speed from low engine speed to target engine speed including engine start. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
The present invention relates to absorbent composites comprising a fibrous material and a relatively large quantity of a particulate, water-swellable, generally water-insoluble absorbent material.
2. Description of the Related Art
Absorbent composites suitable for use in absorbent products such as diapers, training pants, feminine care products, adult incontinence products, and the like are known. As a general rule, the absorbent composites comprise a matrix of fibers. The fiber matrixes tend to have a relatively low specific absorption capacity. Accordingly, absorbent products requiring a relatively high absorbent capacity, and employing such a fiber matrix, tend to be relatively thick and bulky. In an attempt to increase the absorbent capacity of such fiber matrixes, absorbent materials, known in the art as superabsorbents, have been introduced into the fiber matrixes. As a general rule, the fiber of the matrix and the absorbent material are combined in an airstream and deposited on a porous forming surface. Such structures are generally lofty and soft.
In an attempt to produce thinner absorbent composites and products, higher concentrations of absorbent material have been added to the fibers in an attempt to maintain absorption capacity of the absorbent composites while reducing their overall bulk. Unfortunately, the amount of absorbent material that can be contained within a fibrous matrix, due to fiber entrapment, is limited. When this limit is exceeded, the absorbent material present in the fiber matrix tends to migrate out of the fiber matrix during manufacture and transport of the absorbent product. When this occurs, the absorbent material may contact the skin of a user. This is undesirable.
Various methods have been suggested to overcome the problem of containing absorbent material within a fibrous matrix. For example, European Patent 0 085 729 published Nov. 6, 1985, describes a process wherein a fusion adhesive is used to adhere particles of an absorbent material to a substrate. European Patent Application 0 301 772 published Feb. 1, 1989, describes a particle-bonded, nonwoven fibrous web containing liquid-absorbent polymer particles distributed therein and attached to the fibers by the use of an adhesive binder. European Patent Application 0 255 654 describes a process employing a resin binder to adhere absorbent polymer particles in a cellulose fiber web. Lesniak et al. U.S. Pat. No. 4,826,880 issued May 2, 1989, describes absorbent products containing hydrates of particulate absorbent polymers.
The use of adhesive binders, thermoplastic resins, and the like may be sufficient to adhere particles of absorbent material in a fibrous web but may undesirably affect the flexibility of the web and may prove to be too costly or complicated for use in disposable absorbent products. | {
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The present invention pertains to the field of flame detection, and is particularly adapted to prevent false alarms generated by modulated and time varying sources of background radiation such as the sun, welders, hot objects and artificial lights. Flame detectors are presently available which are solar blind to steady sunlight but will not function properly if the sunlight incident on the detector is modulated, or time varying as when an object passes between the sun and the sensor in the sensor's field of view. Modulation of reflected sunlight by ocean waves and ripple is known to cause false alarms at offshore oil platforms with existing flame detection equipment.
Conventional flame detectors also have difficulties in detecting big fires since the high optical intensity emitted by the big fire causes saturation of the electronics following the optical detector. It is known that big fires have a larger proportion of the flicker occurring at higher frequencies than small fires.
U.S. Pat. No. 4,639,598, Kern et al., and U.S. Pat. No. 3,931,521, Cinzori, disclose use of two detectors, one operating at far infrared (7 to 25 microns) and the other at near infrared (0.8 to 1.1 microns) wavelengths. This approach suffers due to several reasons, including a) reduced sensitivity due to lower infrared emission by fires in the far infrared wavelength range as compared to strong CO.sub.2 emission at 4.3 microns from hydrocarbon fires, b) reduced sensitivity of thermal detectors available for the far infrared wavelength range compared to photoconductive detectors for shorter wavelengths, and c) necessity to look at spurious signals in the near infrared, caused by a large number of sources unrelated to fires, and also in the far infrared due to sources strongly emitting such as human or animal presence, both resulting in overburdening of the processor. | {
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Referring to FIG. 1, a driving circuit board 1 and a piezoelectric element 2 of a conventional micro piezoelectric pump are electrically connected to one another by means of two wires 1a.The two ends of each of the wires 1a are soldered to the driving circuit board 1 and the piezoelectric element 2, respectively. When it is desirable that conventional micro piezoelectric pumps be further miniaturized, the wires 1 a are a hindrance to further miniaturization of micro piezoelectric pumps.
The inventor of the present invention found room for improvement in the conventional micro piezoelectric pumps, and thus the inventor devised a wiring structure capable of substituting for the two wires between a driving circuit board and a piezoelectric element and thereby conducive to further miniaturization of micro piezoelectric pumps. | {
"pile_set_name": "USPTO Backgrounds"
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Multi-function machines have been recently developed. These machines commonly include the capability to print a digitally formatted document which is downloaded from a host computer. As is known in the art, the print function of the multi-function machine is realized by utilizing a laser and a polygon mirror to write information on a photoreceptor. The photoreceptor is subsequently placed in contact with a piece of paper which acquires the image written on the photoreceptor.
Prior art multi-function machines also commonly include the capability to digitally copy a document. As is known in the art, the digital copying aspect of these machines is realized through a Charge Coupled Device (CCD) which acquires a digital data representation of an image. The digital image data is then conveyed to the printer portion of the machine which yields a printed document.
Prior art multi-function machines may also include a capability to send and receive facsimile data. Received facsimile data is usually printed in accordance with the printer aspect of the multi-function machine. A document to be sent by facsimile is typically scanned and encoded by the CCD element of the multi-function machine.
Recently, a multi-function machine has been developed which has the capability of combining one or more individual functions. For instance, image data from a computer may be combined with a scanned image to produce a printed image. This device directly prints any merged image data. No capability is provided for routing the merged image data to other data processing devices. | {
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In most modern multi-programmed data processing or computer systems, various tasks or user applications contend for processing time to execute on a central processing unit (CPU) or similar processing device. Activity in even the most highly multi-tasking environment tends to be bursty, having periods of latency or inactivity followed by periods of intense processing activity. Accordingly, it is useful to analyze the utilization of CPUs and other similar data processing system devices for a variety of reasons. For example, high processor utilization during periods in which few or no user tasks are scheduled may be an indicia of a virus program or of some correctable fault in task scheduling resulting in thrashing or other inefficient system behavior. In theory, CPU utilization may be determined by accumulating CPU idle time across a sampling interval to determine the percentage of time the processor is inactive. To accomplish this, a list of tasks or threads is maintained by the OS which are ready-to-run, i.e., not waiting for some event to resume execution. When this ready-to-run list is empty, no tasks are being executed and the processor is idle. Accordingly, a CPU-independent timer is read and the processor is essentially deactivated. This is accomplished by putting the processor in a predefined processor performance state such as the C2 or C3 states defined by the well known Advanced Configuration and Power Interface Specification, Revision 2.0, Jul. 27, 2000 (ACPI). In the C2 state clock signals are removed from the functional units of the processor while its memory subsystem remains active and “snoopable” by other devices. In a C3 state, the clock signal is also removed from this memory portion of the data processing system and a so-called “deep sleep” state is entered. When a new task is added to the ready-to-run list, the processor is placed in an active state (such as the CO ACPI state) and the timer is read again. The difference between the first and second timer reads (multiplied by the timer's period) then represents the CPU's idle time. The accumulation of this time across a sampling interval is then used to determine the CPU utilization (what percentage of the CPU's time is spent idle). Unfortunately, this measure of CPU utilization is difficult to calculate outside of the OS through a supported application programming interface (API). This is because the API is generally unaware of the ready-to-run task list which is known only to the OS. | {
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Exemplary aspects of the present invention relate to image display control methods, image display control apparatus, and image display control programs adapted to display a large-screen image and/or high-resolution image by arranging plural image projection units and projecting partial images from the projection units.
The size of a display provided by a related art single display unit and the resolution of the display have limitations. Related art methods and apparatus for arranging and using plural image display control units to achieve a large screen exceeding the limitation or a display of high resolution exceeding the limitation are available. At this time, a method of how to make unnoticeable the boundaries between the displays provided by the individual display units to provide one natural display as a whole is a problem to be addressed and/or solved.
Related art methods of making unnoticeable the boundaries are roughly classified into two major categories: combining method and overlapping method. The feature of the composite method is that any point on the whole displayed image is displayed by any one display unit. The feature of the overlapping method is that regions capable of being displayed by the individual display units are made to overlap with each other and that a display on such overlapping regions is superimposingly provided by the plural display units.
One example of the composite method is a method using a mechanical combination. This method includes mechanically bonding together flat-panel display units (e.g., liquid crystal display units) themselves at their edges. This has the advantage that once the units have been bonded, the state is maintained stably. However, it is difficult to create a display device having bondable edges.
Another composite method uses image projection units. Images projected by image projection units are apparently combined on the surface of the display. This makes it unnecessary to bond together display units themselves and hence the apparatus has a relatively large number of degrees of freedom. However, the composite state produces error due to mechanical or electrical aging of the apparatus because mechanical bonding is not used. Furthermore, the errors greatly affect the display quality. It is difficult to maintain good state of display.
One example of the overlapping method is a method of using plural image projection units. A part of an image projected from one image projection unit is superimposed on a part of an image projected from the other image projection unit.
In particular, one output is gradually reduced in an overlapping region while the other output is gradually increased at the same time. Thus, boundary regions are connected smoothly. This overlapped state produces error due to mechanical or electrical aging of the apparatus in the same way as the composite method. However, in the overlapping method, error affects the quality of display to a lesser extent than in the composite method. However, it is difficult to control the display in the overlapping region.
These are described in further detail below with reference to the drawings.
FIG. 21 is a schematic of a related art composite method using plural (four, in this example) image projection units (such as projectors) PJ1, PJ2, PJ3, and PJ4. As shown in this FIG. 21, the image projection units PJ1, PJ2, PJ3, and PJ4 are arranged such that their respective display regions A1, A2, A3, and A4 can be displayed without overlap or gap. However, the display provided by each of the image projection units PJ1, PJ2, PJ3, and PJ4 easily deforms into an irregular quadrilateral having no right angles due to slight installation error or aging. Therefore, it is difficult to precisely arrange their display regions A1, A2, A3, and A4 in this way and to maintain the arrangement.
FIG. 22 is a schematic of a case in which the four image projection units PJ1, PJ2, PJ3, and PJ4 display the individually displayable display regions A1, A2, A3, and A4 such that there are overlapping regions Z in parts of the regions A1-A4. In this related art method, a display can be provided either by the composite method or by the composite method.
FIGS. 23A-23D show a method of providing a display by the composite method of FIG. 22. To simplify the explanation, only the three image projection units PJ1, PJ2, and PJ3 are taken into account. Also, only processing on one line is herein considered. It is assumed that the three image projection units PJ1, PJ2, and PJ3 already know what regions of the displayable display regions of the image projection units overlap with each other.
Specific related art methods for knowing the overlapping regions include methods described, for example, in JP-A-H8-294073 and JP-A-2002-238064, respectively. The method described in JP-A-H8-294073 permits the user to have a clear view of both ends of each overlapping region. The method lets the user indicate the overlapping regions, whereby the method knows them. The method described in JP-A-2002-238064 knows overlapping regions using an entry made by a camera.
FIGS. 23A-23C indicate the values of weights about displays provided by the three image projection units PJ1, PJ2, and PJ3 on some line. As shown in the figure, each weight has two values, “1” and “0”. They can be quite easily implemented in software or by a circuit. Here, the weight “1” means the output value itself is responsive to some input. Also, the weight “0” means a black output. P1, P3, P4, and P6 in the figure indicate the end points of the overlapping regions. P2 and P5 indicate image division positions to carry out a composition in this example. One specific example of implementation of the method of FIG. 23 is described in JP-A-2002-277958. The sum of these weights is a constant value of“1” over the whole display region as shown in FIG. 23D.
FIGS. 24A-24D show the image projection unit PJ2 located in the center of FIGS. 23A-23D has shifted ΔX in the direction of the arrow X. At this time, summation of the weights of the displays shown in FIGS. 24A-24C, respectively, produces portions of weight 0 (i.e., black portions that provide no display) and portions of weight 2 (i.e., very bright portions because of superimposition of displays) as shown in FIG. 24D. These can be quite easily discerned visually. The quality of display deteriorates greatly.
FIGS. 23A-23D and 24A-24D assume only processing on same line. Where a two-dimensional way of thinking is introduced, more difficult circumstances will exist.
FIGS. 25A-25C illustrate this. As shown in FIG. 25A, a case in which display regions A1 and A2 of two image projection units PJ1 and PJ2 overlap with each other at an angle is disclosed. It is assumed that the display region A1 of the image projection unit (referred to as the image projection unit PJ1) displaying the left side of FIGS. 25A-25C is a region in gray color of FIG. 25A and that the display region A2 of the image projection unit (referred to as the image projection unit PJ2) displaying the right side of FIGS. 25A-25C is a region in gray color of FIG. 25B.
As shown in FIG. 25C, the display regions A1 and A2 of the both image projection units PJ1 and PJ2 overlap with each other, producing a portion (portion al in gray color) of excessive brightness. Also, a portion (black portion a2) that is displayed by none of the image projection units PJ1 and PJ2 exists. This is a phenomenon that cannot be avoided in the case where the minimum unit of display of the image projection units has a finite size and the displays of image projection units overlap at an angle.
FIGS. 26A-26D show a method of achieving a display provided by the overlapping method. FIGS. 26A-26C show the values of weights on some line of the displays provided by the three image projection units PJ1, PJ2, and PJ3.
As shown in FIGS. 26A-26D, one weight gradually decreases in the overlapping region, while the other increases gradually. Summation of the weights produces a constant value over the whole display region as shown in FIG. 26D.
FIGS. 27A-27D show a circumstance in which the image projection unit PJ2 located in the center of FIG. 26 has produced a positional deviation in the same way as in FIGS. 24A-24D. At this time, summation of the weights of the displays shown in FIGS. 24A-24C produces unevenness as shown in FIG. 27D. This indicates that deterioration of the display quality due to a positional deviation is smaller, as can be seen by comparison with FIGS. 24A-24D showing an example of the composite method. That is, concave portions of the weights are displayed slightly darkly. Conversely, convex portions are displayed slightly brightly. This indicates the superiority of the overlapping method over the composite method in which black and bright lines are noticed clearly as to positional deviation of image projection units.
However, it is not so straightforward to connect images in the overlapping regions smoothly, because a nonlinear relation exists between the input to each image projection unit and the display output (output brightness) due to gamma correction to adjust the nonlinear characteristics of the human perception.
FIG. 28 is a schematic of the aforementioned nonlinear relation between the input and output. In particular, the human perception has logarithmic characteristics. Where a proportional relation is created between the input and the output brightness, it follows that variations in the output brightness are felt to be greater at small inputs while variations in the output brightness are felt to be smaller at large inputs. As a result, as shown in FIG. 29, it is not felt that twice of the value of the output brightness when the input value is 127, for example, is a value close to the output brightness when the input value is 255. Therefore, in a normal display device, the correspondence between the input and output brightness is often set to a function inverse to a function as shown in FIG. 28 such that the value of the brightness perceived by a human approaches the input value. Specifically, the function of FIG. 28 is upwardly convex. As a function inverse to this function of FIG. 28, a downwardly convex relation is often set.
The effects of the nonlinearity are particularly shown in FIGS. 30A and 30B. As shown in FIG. 30A, it is assumed that an input value to be displayed (i.e., output value) is constant. In this case, if the sum of input values to the respective image projection units in the overlapping region is made constant, the sum of the output values decreases in the overlapping region as shown in FIG. 30B, for the following reason. As described previously, a downwardly convex nonlinear relation exists between the input value and output value as an inverse function to the function of FIG. 28.
FIGS. 31A and 31B illustrate a method of correcting this and making constant the output value over the overlapping region. To make constant the output value as shown in FIG. 31B, it is necessary to gradually nonlinearly increase or reduce the input to each image projection unit in the overlapping region as shown in FIG. 31A. The nonlinearity depends on the function shown in FIG. 28. The function varies depending on the value of the gamma adjustment or the nonlinearity of other component. Furthermore, the nonlinearity changes depending on user's change of settings or varies due to aging characteristics. Accordingly, in order to control the sum of the output values to a desired value, it is necessary to perform nonlinear processing including many parameters. | {
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The present invention relates to improvements to the treatment of wastewater using activated sludge processes. It relates more particularly to a process and to a plant for controlling the retention time of the sludge undergoing clarification in a process for the treatment of wastewater by activated sludge comprising a recirculation of the activated sludge from the clarification stage to the aeration stage.
It is known that in such activated sludge processes, the recirculation of the sludge is a significant component in the overall operation of purification plants. The role of the secondary clarifiers consists in separating the sludge from the treated water, and to do this a sludge-concentrating stage is essential in the structure. This concentrating phase requires a retention time imposed on the sludge in the clarifier, and, if this retention time is not controlled, the process drifts towards malfunction logic.
Too long a retention time firstly results in anoxia conditions, with an immediate effect of potential denitrification and the appearance of froth on the surface of the clarifiers. Secondly, the sludge comes into anaerobic conditions, the repercussions of which are often disastrous on the water system and the treatment of the sludge since the development of filamentous microorganisms is favoured, which causes, over the entire plant, foaming problems and problems of poor flock settling (a rise in the Mohlman index). The risk of sludge egress is t hen increased in the event of a hydraulic surge. In addition, anaerobic conditions are completely incompatible with biological dephosphatizing processes, and in this case the release of phosphorous into the clarifier results in the discharges being immediately off-specification. These events are thus characteristic of a major malfunction of the water system. In parallel, and from a direct economic standpoint, the sludge treatment is not optimized when the flock-settling properties are poor, whatever the treatment system involved. The operating times of the equipment of the sludge treatment system are lengthened, the solids contents are reduced and, immediately, the volumes of sludge extracted are increased for the same mass of treated dry matter.
In the clarification stage, the retention time of the sludge must therefore remain limited, with the risk of causing malfunctions in the water treatment. This limit is about 2 hours in the case of activated sludge processes operating with prolonged aeration. It is less in the case of moderate or high load conditions.
On the other hand, too short or variable a retention time for sludge under clarification may also be a limiting factor in the case of sludge treatment systems. This is because it gives rise to a sludge concentration not suitable for certain thickening and dehydrating structures when the sludge is extracted from the recirculation line. This is generally the case for small-sized and medium-sized plants equipped with structures for thickening by draining. The dilution of the sludge entering this type of equipment results in insufficient capture rates or in the need for excessive dosing with flocculating polymer, resulting in risks of blockage. variations in load on these conditioning apparatuses often result in malfunctions, such as creep or blockage, which are connected with the modifications in the operating conditions predefined during the initial set-up operations. The minimum permitted concentration on the draining screens or tables is about 6 g/l. The variations in loads withstood by this type of equipment are about 10 to 20%. These conditions on the concentration, which corresponds to the concentration encountered in the sludge well, are directly connected with a constraint on the minimum retention time in the clarification stage. This minimum retention time itself depends on the sludge settleability properties.
Maintaining and controlling a mean retention time of the sludge undergoing clarification are therefore of prime importance for ensuring quality, reliability and economy of the treatment. This is indeed the technical problem that the present invention aims to solve.
In the technology of water treatment with regard to the activated-sludge recirculation function, two types of recirculation in a purification plant may be identified:
recirculation which returns the sludge from the clarifier into the aeration basin: the objective is to recycle part of the biological sludge so as not to impoverish the purifying mass of the aeration basin;
recirculation of mixed liquors which exist in the plants having an anoxia basin and an aeration basin; they recover the sludge from the aeration basin rich in nitrates in order to bring it into the anoxia region so that the denitrification can reduce the contents of the discharges.
The process forming the subject-matter of the present invention relates to the recirculation of activated sludge from the clarifier into the aeration basin. Given that the various arrangements for the activated sludge to be recirculated from the clarifier into the aeration basin form part of the conventional technical knowledge of those skilled in the art in the water treatment field, they will not be described. The reader may refer for this purpose to Mxc3xa9mento Technique de l""Eau, Ninth Edition (1989).
The general principle of managing the recirculation of activated sludge in water treatment will now be explained.
The objectives of management suitable for sludge recirculation must satisfy the criteria below:
to prevent the sludge in the clarifier from undergoing anaerobiosis in order to reduce any risk of malfunction;
to adapt the operating mode of the plant to the conditions encountered in operation (sludge masses in the system, sludge-settling properties, rain showers, etc.), so as in particular to prevent sludge bed egress;
to manage the distribution of the total mass of sludge between the biological basin and the clarifier in order to make the biological treatment reliable.
Reference is made to FIG. 1 of the appended drawings, which is a diagram illustrating the construction of the sludge flow balance and in this diagram the aeration basin is represented by 1 and the clarifier by 2.
The amount of recirculation of the sludge from the clarifier 2 into the aeration basin 1 is by definition the ratio of the rate of recirculation to the throughput of the plant:
xcfx84rec=Qr/Qt
where xcfx84rec denotes the rate of recirculation (0 less than xcfx84rec less than 1)
Qr denotes the rate of recirculation (m3/h) and
Qt denotes the throughput (m3/h).
This amount of recirculation is defined by the conditions encountered on the site. There must be an overall balance between the sludge flows into and out of the clarifier:
(Qt+Qr)xc3x97Cas=Qrxc3x97Cr
where Cas is the sludge concentration (g/l) in the aeration basin and
Cr is the sludge concentration (g/l) in the recirculation line.
The storage term is neglected here, just like the treated-water discharge outflow.
This equation is used to calculate the degree of recirculation xcfx84rec:
xe2x80x83xcfx84rec=Qr/Qt=Cas/(Crxe2x88x92Cas)
Cas is an operational parameter that can be measured directly in the aeration basin. As regards Cr, this must be controlled so as to meet the requirements on the retention time of the sludge in the clarifier since it has been seen, empirically, that the sludge retention time is linked to the Mohlman index, representative of the sludge-settling and thickening properties, and to the sludge concentrations in the aeration basin and in the recirculation line. The following correlation has been established between these variables:
RT/60=(CrMI/1000)3xe2x88x92(CasMI/1000)3
where RT is the retention time (in minutes) of the sludge undergoing clarification and
MI is the Mohlman index (ml/g).
This formula is the reference relationship for the automated recirculation management logic tool. It is based on a formula of the same type published by ATV (ATV Standard, A 131. (1991); xe2x80x9cDimensioning of single-stage activated sludge plants upwards from 5 000 total inhabitants and population equivalentsxe2x80x9d Abwassertechnische Vereinigung e.V., St. Augustin): C r = 1000 RT / 60 3 MI
If the measurement of the Mohlman index is not representative of the fact of the lack of sludge settling, a settling index Is may be defined for safety protection, and then used in these formulae.
Is is the undiluted settling index (ml/g).
In practice, the maximum permitted retention time of the sludge undergoing clarification is only dependent on the mass charge of the plant. As an indication, it is about 120 minutes for a low charge. It may be reduced to 40 minutes for high charges.
For a given charge, since the settling index and the sludge concentration in the aeration basin are operating parameters, it is thus possible to define a setpoint for the sludge concentration in the recirculation line which overall satisfies, with respect to the maximum permitted retention time in the clarifier, the constraint associated with making the water treatment reliable.
The amount of recirculation defined will thus be a function of the sludge concentration in the aeration basin and, indirectly, of the sludge settling index and of the mass charge of the plant, that is to say of the operating conditions encountered on the site. This amount of recirculation can therefore be expressed as:
xcfx84rec=Qr/Qt=Cas/(Cr,setxe2x88x92Cas)
where
Cr,set=1000/MI(RTmax/60+(CasMI/1000)3)⅓;
Cr,set is the setpoint for the sludge concentration (g/l) in the recirculation line; and
RTmax is the maximum permitted retention time (in minutes) of the sludge undergoing clarification.
In fact, to be rigorous it would be necessary to complete the balance equation with the flow of extracted sludge into the sludge treatment system. This quantity may sometimes be predominant for the outflows in small plants:
(Qt+Qr)xc3x97Cas=(Qr+Qext)xc3x97Cr,set
where Qext is the extraction flow rate (m3/h).
The calculated rate of recirculation is then:
Qr=[(Qtxc3x97Cas)xe2x88x92(Qextxc3x97Cr,set)]/(Cr,setxe2x88x92Cas).
The management methods known at the present time for recirculating sludge in the field of water treatment by activated sludge will now be explained.
In general, two management methods are used:
the recirculated flow rate is constant and represents from 100 to 150% of the intended daily wastewater throughput of the plant. Above a limiting throughput threshold, the recirculation equipment may have to be forced;
the rate of recirculation is slaved in a proportional manner to the incoming flow rate.
In order to proportion the rates of recirculation, the operation of the equipment is continuous at a fixed rate, or syncopated by slaving to a clock or to a cyclic metering device. In large plants, specific regulations exist which use a combination of sensors for the throughput, the rate of recirculation, the weight of sludge in the aeration basin and in the recirculation line, the height of the sludge blanket and the output turbidity.
A well-managed recirculation favours good quality of the sludge and clarification of the water. The sludge must not be stored in the clarifier in order to prevent fermentation. The operating periods must always be longer than the rotation time of the scraper bridge of the clarifier or at least managed on the basis of non-harmonic frequencies.
If the sludge concentration is adapted and if the recirculation is well managed, the sludge blanket is not visible and cannot be detected with the Secchi disc: the sludge blanket is at most 1 m in depth.
These management methods according to the prior art have the following drawbacks:
1xe2x80x94The conventional recirculation management methodsxe2x80x94fixed or slaved flow ratexe2x80x94remain dependent on the definition of an average amount of recirculation and therefore on a control setting tied to the operating conditions. Too often, the actual amounts of recirculation are defined when designing and commissioning the plants. They are only rarely re-adjusted, with the exception of periods of malfunction (a typical example: a leak in the sludge bed is observed and the immediate reaction is to increase the recirculation. Unfortunately, this operating reaction occurs too late). One of the essential management rules might be to re-update the amounts of recirculation when a Mohlman index and/or sludge concentration measurement is made in the aeration basin and to modify the settings as a consequence. Apart from this main defect, managing the recirculation on the basis of a fixed flow rate has the drawback of not being good in taking account of the hydraulic events encountered. Peak management is rarely modified according to the daily regimes (working days or weekends) and the various seasonal regimes are treated in the same way (summer periods, rainy periods, temporary activities (grape harvesting, etc.)), and the forced operations actuated by rainy weather are blind to the history and to the environment of the event (sudden or uniform, short or persistent rainfall).
2xe2x80x94The management method slaved to the flow rate seems to be more suitable in this field. However, from a rigorous standpoint, it appears that the dynamics of sludge transfer in the aeration basin/clarifier system have not been taken into account hitherto. This is because the response of the system is slow and damped by buffer effects, and the reaction to a rapid event cannot be simply controlled by an action proportional to the excitation.
3xe2x80x94Finally, the method of controlling the recirculation equipment is ordinarily syncopated, and the modifications to the settings often result in a phase lag in the syncopating frequencies with the rotation time of the scraper bridge of the clarifier. The non-harmonic frequencies as they are known are no longer respected and the recirculated sludge always comes from the same regions of the bottom of the clarifier. This is because the scraper has a mainly destructuring action, since the relative compactness of the sludge blanket limits homogeneous recovery of the sludge by suction towards the sludge well. Passage of the scraper locally fluidifies the sludge blanket and encourages the recovery of freshly destructured sludge upon activating the recirculation pumps. For harmonic frequencies (15 minutes operation, 15 minutes stoppage for a bridge rotation time of 30 minutes for example), sludge recovery is effective only over part of the clarifier.
Unsuitable management of the sludge recirculation runs the risks mentioned below:
a)xe2x80x94Excessive Recirculation:
The risks run by excessive recirculation are too high a velocity in the internal xe2x80x9cskirtxe2x80x9d of the settler (xe2x80x9ccliffordxe2x80x9d) acting as a distributor of the flux to be treated (impeded settling) and an imbalance at the water/sludge interface: the rate of sludge pumping will be much higher than the particle settling velocity, thus creating a hydraulic short-circuit. In addition, excessively high rates of recirculation reduce the sludge concentrations in the recirculation line, which may place a limit on the feed for the sludge treatment system.
b)xe2x80x94Insufficient Recirculation:
The risks run as a consequence of insufficient recirculation are linked with possible uncontrolled denitrification and to the sludge moving to anaerobic conditions in the clarifier (release of phosphorus, promotion of the development of filamentous microorganisms and of foam, etc.). The clarifier is periodically converted into a sludge storer and thickener.
c)xe2x80x94Syncopated Recirculation with a Non-harmonic Frequency:
The risks are identical to those of insufficient recirculation, but in a less pronounced manner, by the creation of regions or unrecovered pockets of sludge, the retention time of which is long.
In the case of clarifiers with sucked bridges, the rate of recirculation must never be
less than the rate of depriming of the siphon
such that there is an imbalance in the load losses on the suction tubes (this depends intimately on the distribution of the sludge concentrations on the bottom).
Given the fact that the existing strategies for managing the recirculation of activated sludge are not satisfactory, the objective of the present invention is to provide a process for the automated management of this recirculation, for the purpose of controlling the retention time of the sludge undergoing secondary clarification in activated-sludge processes. Its primary objective is to limit the retention time of the sludge in the clarifier to below a maximum limit, for the purpose of making the water treatment reliable. Its secondary objective is to facilitate the management of sludge treatment systems using, for example, draining equipment, by maintaining a constant concentration in the recirculation line.
Consequently, the subject of the present invention is a process for controlling the retention time of the sludge undergoing clarification in a process for treating wastewater by activated sludge comprising a recirculation of the activated sludge from the clarification stage into the biological basins, characterized in that the rate of sludge recirculation (Qr) is varied so as to maintain a constant recirculated sludge concentration (Cr) while at the same time guaranteeing a retention time (RT) of the sludge undergoing clarification of less than a critical value (RTmax).
According to one method of implementing the invention, the rate of sludge recirculation (Qr) is varied according to a signal representative of the throughput (Qt) of water passing through the plant, so as to limit the retention time of the sludge in the clarification stage.
According to another method of implementation, when the validity of the signal representative of the throughput of water passing through the plant is not recognized, the recirculation of the sludge is controlled according to the fall-back method of managing the water treatment plant.
According to another method of implementing the process according to the invention, the rate of sludge recirculation (Qr) is varied according to a signal representative of the sludge concentration (Cr) in the recirculation line, obtained from a sensor positioned in the recirculation line, this signal being delivered to an automated logic tool which varies the rate of recirculation (Qr) according to the variation in the signal received, so as to keep the sludge concentration (Cr) in the recirculation line constant; in the event of doubt about the representativeness of the said signal, the sludge recirculation is controlled automatically according to a slaved management method whose objective is to limit the retention time of the sludge in the clarification stage, the said slaved management method being managed on the basis of the analysis of the values of the sludge concentration (Cas) in the biological basin and on the basis of the throughput (Qt) of water passing through the plant.
According to another characteristic of the process according to the invention defined above, the volume of settled sludge is periodically measured so as to evaluate the sludge settling index (Is) and the sludge concentration in the biological basin and to determine the setpoint values for the management controller.
According to the present invention, the automated logic tool for managing the sludge recirculation is designed so as:
to periodically update the average amount of sludge recirculation (xcfx84rec) so as to adapt it to the conditions of the treatment plant, on the basis of the value of the sludge concentration (Cas) in the aeration basin and on the basis of the re-updated settling index (Is);
to respond instantly to the hydraulic events and manage the reaction delays according to the response time of the clarifier/aeration basin system by being based on the variation in the throughput (Qt); and
keeping the sludge concentration (Cr) in the recirculation line constant.
The invention also relates to apparatuses for implementing the process defined above.
According to a first embodiment, this apparatus comprises:
sensors making it possible, respectively, to measure the throughput (Qt);
means ensuring modulated control of the said rate of activated sludge recirculation (Qr);
means for measuring the volume of the sludge that has settled and for evaluating the settling index (Is) and the sludge concentration (Cas) in the biological basin;
a controller ensuring automated management of the recirculation, which comprises two main modules served by a common signal-input stage:
a first module providing the interface between the user and the controller and making it possible to display a concentration setpoint (Cr);
a second module forming the unit for controlling the recirculation flow rates and comprising:
a control logic tool for controlling the retention time of the sludge in the clarifier on the basis of the throughput (Qt), in order to calculate a signal for controlling the rate of recirculation (Qr);
a module for managing the safety actions of the logic tool for managing the recirculation means; and
a stage involving the parameterization, reception, processing, analysis and validation of the signals coming from the sensors and logic indicators of the operation of the equipment in order to supply the said modules.
According to a second embodiment, this apparatus comprises:
sensors making it possible, respectively, to measure:
the sludge concentration (Cr) in the line for recirculating the activated sludge from the clarifier into the aeration basin;
the sludge concentration (Cas) in the aeration basin; and
the throughput (Qt);
means ensuring modulated control of the said rate of activated sludge recirculation (Qr);
means making it possible to measure the volume of the sludge that has settled and to evaluate the settling index (Is);
a controller ensuring automated management of the recirculation, which comprises three main modules served by a common signal-input stage:
a first module providing the interface between the user and the controller and making it possible to display a concentration setpoint (Cr);
a second module forming the unit for controlling the recirculation rates and which comprises:
a control logic tool ensuring control and regulation of the rate of recirculation (Qr) on the basis of the measurement of the sludge concentration (Cr) in order to keep the recirculation concentration constant;
a control logic tool ensuring control of the retention time of the sludge in the clarifier on the basis of measurements of the sludge concentration (Cas) in the aeration basin and of the throughput (Qt), in order to calculate a signal for controlling the rate of recirculation (Qr);
a module for managing the safety actions of the logic tool for managing the recirculation means; and
a third module for calculating the mass of sludge present in the clarifier/biological basin system for the purpose of fixing and setting the rate of extraction of the sludge; and
a stage involving the parameterization, reception, processing, analysis and validation of the signals coming from the sensors and logic indicators of the operation of the equipment in order to supply the said modules.
As will have been understood, the process forming the subject-matter of the present invention allows the rate of recirculation to be varied so as to maintain a constant concentration of recirculated sludge, while at the same time guaranteeing a retention time of less than the critical value. One of its functions furthermore makes it possible to evaluate the total mass of sludge present in the system, so as to assist the management of the extractions. Finally, the safety detection provided by the controller prevents any possible drift in the quality of the sludge or in the components providing the recirculation function, and informs when exceptional maintenance operations are to be carried out.
The process forming the subject-matter of the invention makes it possible in particular to eliminate the risk of filamentous bacteria appearing from the sole fact of managing the secondary clarifiers. Thus, it makes the water treatment system reliable and makes it possible to optimize the performance of the sludge system by maintaining the quality of the sludge. Finally, the constancy of the extraction concentration and the possibility of renewing the predefined settings or of operating the equipment at any time make it possible to assist the operations relating to thickening by draining. The advantage of applying this automated management may be expressed in terms of operating costs:
Improvement in or maintenance of sludge quality, manifested by a low Mohlman index (increase in the capacity and reduction in the operating time of the sludge treatment equipment, improvement in the solids content and reduction in the volumes and in the costs of extracting the sludge produced, reactant metering, reduction in returns to the top, etc.).
Assistance in sludge treatment and elimination of draining malfunctions (organization of operating labour).
Conformity of the discharges (Water Agency Agreements and Premiums).
Prevention of malfunctions, especially under extreme operating conditions and during rain showers (organization of labour and elimination of malfunction handling costs).
Visual appearance of the clarifier.
Further features and advantages of the present invention will become apparent from reading the description given below with reference to the appended drawings which illustrate various methods of implementation and embodiments. In the drawings: | {
"pile_set_name": "USPTO Backgrounds"
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Sometimes, a user of a computer participating in a wireless network needs to newly add a device such as a printer to the wireless network. In such a situation, the following user operations are required. First, the user operates the user's computer to change setting for wireless communications to an initial state so as to enable the user's computer to temporarily establish a wireless connection with the printer. After the temporal wireless connection is established, the user further operates the computer to send predetermined setting data for wireless communications to the printer. Next, the user operates the printer so as to apply the predetermined setting data transmitted from the computer to the printer, so that a proper wireless connection can be established between the computer and the printer. An example of such a wireless communication system is disclosed in Japanese Patent Provisional Publication No. 2003-143156.
The above mentioned setting method for newly adding a device to the wireless network requires the user to operate the device to adjust setting for wireless communications in accordance with the setting data of the user's computer in addition to requiring the user to operate the user's computer to change the setting to an initial state. Such user operations are very troublesome for the user. If the user is not familiar with wireless networks, such user operations are very difficult for the user. | {
"pile_set_name": "USPTO Backgrounds"
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To test a material with the eddy current method, a coil is moved into proximity with a test piece, the coil inducing eddy currents in the test piece by producing magnetic alternating fields. Such induced eddy currents produce a secondary field in the coil or in a respective sensor coil. The signals appearing during a scanning cycle at the output of the coil or sensor coil are converted into a sequence of digital values corresponding to complex numbers.
During the testing of materials with the eddy current method, very often disturbing effects will appear, generating higher and/or different signal levels than those generated by the defects present in the material being tested. Such disturbance effects are caused, e.g., by the lifting of the coil from the test piece, by ferritic influx in the material, etc. In order to detect the flaws, these interfering signals must be separated from those signals caused by the defects in the material For this separation one can use the amplitudes and the phase positions of the complex values. Many times, however, it is not possible to definitely assign the flaw signals and disturbance signals to certain amplitude and phase ranges.
In a multifrequency testing apparatus, one uses linear algorithms to distinguish the flaw signals from the disturbance signals (i.e., these signals attributable to field variations produced by phenomena other than flaws in the material). Thereby stationary independent data measured at different measuring frequencies are combined by matrix operations in order to generate zero points in the directions of the disturbance producing the disturbance field to be suppressed. Flaw signals are indicated only when the phase of the disturbance signals falls within a predetermined range. As the amplitude of the disturbance signal increases, so do the phase angles relative to the direction of the disturbance. If the size of the defect influences not only the amplitude but also the phase position, this will result in losses unfavorably affecting the determination of the defect size. These losses will appear independent therefrom whether or not a disturbance signal is coinciding with a flaw signal. | {
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The new cultivar was discovered as a result of a planned breeding program directed by the inventor, Akiko Kitahara, a citizen of Japan. The seed parent is the unpatented variety of Phlox subulata ‘Mont Blanc’ and the pollen parent is an unnamed, unpatented variety of Phlox stolonifera. The cross resulting in ‘PPPHL07301’ was made Apr. 19, 2006. The new variety was discovered Sep. 20, 2007, by the inventor in a non-commercial nursery in Higashiomi Shiga, Japan.
Asexual reproduction of the new cultivar ‘PPPHL07301’ by vegetative cuttings was first performed Sep. 25, 2007 at a non-commercial nursery in Higashiomi Shiga, Japan. Multiple generations have since been produced and have shown that the unique features of this cultivar are stable and reproduced true to type in successive generations. The new cultivar was first sold and made available to the public in April 2011. | {
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A number of patents and publications are cited herein in order to more fully describe and disclose the invention and the state of the art to which the invention pertains. Each of these references is incorporated herein by reference in its entirety into the present disclosure, to the same extent as if each individual reference was specifically and individually indicated to be incorporated by reference.
Throughout this specification, including the claims which follow, unless the context requires otherwise, the word “comprise,” and variations such as “comprises” and “comprising,” will be understood to imply the inclusion of a stated integer or step or group of integers or steps but not the exclusion of any other integer or step or group of integers or steps.
It must be noted that, as used in the specification and the appended claims, the singular forms “a,” “an,” and “the” include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to “a pharmaceutical carrier” includes mixtures of two or more such carriers, and the like.
Ranges are often expressed herein as from “about” one particular value, and/or to “about” another particular value. When such a range is expressed, another embodiment includes from the one particular value and/or to the other particular value. Similarly, when values are expressed as approximations, by the use of the antecedent “about,” it will be understood that the particular value forms another embodiment.
This disclosure includes information that may be useful in understanding the present invention. It is not an admission that any of the information provided herein is prior art or relevant to the presently claimed invention, or that any publication specifically or implicitly referenced is prior art.
Checkpoint Kinase 1 (CHK1)
Progression through the cell division cycle is a tightly regulated process and is monitored at several positions known as cell cycle checkpoints (see, e.g., Weinert and Hartwell, 1989; Bartek and Lukas, 2003). These checkpoints are found in all four stages of the cell cycle; G1, S (DNA replication), G2 and M (Mitosis) and they ensure that key events which control the fidelity of DNA replication and cell division are completed correctly. Cell cycle checkpoints are activated by a number of stimuli, including DNA damage and DNA errors caused by defective replication. When this occurs, the cell cycle will arrest, allowing time for either DNA repair to occur or, if the damage is too severe, for activation of cellular processes leading to controlled cell death.
All cancers, by definition, have some form of aberrant cell division cycle. Frequently, the cancer cells possess one or more defective cell cycle checkpoints, or harbour defects in a particular DNA repair pathway. These cells are therefore often more dependent on the remaining cell cycle checkpoints and repair pathways, compared to non-cancerous cells (where all checkpoints and DNA repair pathways are intact). The response of cancer cells to DNA damage is frequently a critical determinant of whether they continue to proliferate or activate cell death processes and die. For example, tumour cells that contain a mutant form(s) of the tumour suppressor p53 are defective in the G1 DNA damage checkpoint. Thus inhibitors of the G2 or S-phase checkpoints are expected to further impair the ability of the tumour cell to repair damaged DNA.
Many known cancer treatments cause DNA damage by either physically modifying the cell's DNA or disrupting vital cellular processes that can affect the fidelity of DNA replication and cell division, such as DNA metabolism, DNA synthesis, DNA transcription and microtubule spindle formation. Such treatments include for example, radiotherapy, which causes DNA strand breaks, and a variety of chemotherapeutic agents including topoisomerase inhibitors, antimetabolites, DNA-alkylating agents, and platinum-containing cytotoxic drugs. A significant limitation to these genotoxic treatments is drug resistance. One of the most important mechanisms leading to this resistance is attributed to activation of cell cycle checkpoints, giving the tumour cell time to repair damaged DNA. By abrogating a particular cell cycle checkpoint, or inhibiting a particular form of DNA repair, it may therefore be possible to circumvent tumour cell resistance to the genotoxic agents and augment tumour cell death induced by DNA damage, thus increasing the therapeutic index of these cancer treatments.
CHK1 is a serine/threonine kinase involved in regulating cell cycle checkpoint signals that are activated in response to DNA damage and errors in DNA caused by defective replication (see, e.g., Bartek and Lukas, 2003). CHK1 transduces these signals through phosphorylation of substrates involved in a number of cellular activities including cell cycle arrest and DNA repair. Two key substrates of CHK1 are the Cdc25A and Cdc25C phosphatases that dephosphorylate CDK1 leading to its activation, which is a requirement for exit from G2 into mitosis (M phase) (see, e.g., Sanchez et al., 1997). Phosphorylation of Cdc25C and the related Cdc25A by CHK1 blocks their ability to activate CDK1, thus preventing the cell from exiting G2 into M phase. The role of CHK1 in the DNA damage-induced G2 cell cycle checkpoint has been demonstrated in a number of studies where CHK1 function has been knocked out (see, e.g., Liu et al., 2000; Zhao et al., 2002; Zachos et al., 2003).
The reliance of the DNA damage-induced G2 checkpoint upon CHK1 provides one example of a therapeutic strategy for cancer treatment, involving targeted inhibition of CHK1. Upon DNA damage, the p53 tumour suppressor protein is stabilised and activated to give a p53-dependent G1 arrest, leading to apoptosis or DNA repair (Balaint and Vousden, 2001). Over half of all cancers are functionally defective for p53, which can make them resistant to genotoxic cancer treatments such as ionising radiation (IR) and certain forms of chemotherapy (see, e.g., Greenblatt et al., 1994; Carson and Lois, 1995). These p53 deficient cells fail to arrest at the G1 checkpoint or undergo apoptosis or DNA repair, and consequently may be more reliant on the G2 checkpoint for viability and replication fidelity. Therefore abrogation of the G2 checkpoint through inhibition of the CHK1 kinase function may selectively sensitise p53 deficient cancer cells to genotoxic cancer therapies, and this has been demonstrated (see, e.g., Wang et al., 1996; Dixon and Norbury, 2002).
In addition, CHK1 has also been shown to be involved in S phase cell cycle checkpoints and DNA repair by homologous recombination. Thus, inhibition of CHK1 kinase in those cancers that are reliant on these processes after DNA damage, may provide additional therapeutic strategies for the treatment of cancers using CHK1 inhibitors (see, e.g., Sorensen et al., 2005). Recent data using CHK1 selective siRNA supports the selective inhibition of CHK1 as a relevant therapeutic approach, and suggests that combined inhibition with certain other checkpoint kinases provides no additional benefit and may be non-productive (see, e.g., Xiao et al., 2006). Small-molecule selective inhibitors of CHK1 kinase function from various chemical classes have been described (see, e.g., Tao and Lin, 2006). | {
"pile_set_name": "USPTO Backgrounds"
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Window blind units constructed of wooden slats effectively provide both aesthetic qualities and light-control utility for home or commercial installations. Such window blind unit construction includes a plurality of wooden slats vertically aligned with each other, with mechanisms for raising and lowering the blind units and arranging the angle of the slats.
In addition to having a plurality of slats, a window blind unit commonly has a bottom rail parallel with the last slat and into which spaced pull cords enter and are anchored. The bottom rail generally is thicker, and therefore heavier, than the slats to thereby provide weight and direction to the slats in maintaining the blind unit in place. The top of a window blind unit typically houses respective mechanisms for raising and lowering the slats and bottom rail and for adjusting the angle of the slats. Housing construction usually is a metal enclosure which, many times, is covered with a valance that blends with the style, color, etc. of the slats and bottom rail. If the blind unit is mounted within a window casing, the valance generally is of one piece construction and is the width of the slats and bottom rail. If the blind unit is mounted to extend laterally outside of the window casing, then the valance is provided with three panels (two lateral, one front) whose adjoining corners can be mitred to produce a meeting, non-overlapping joint. In that construction the two lateral panels protrude outwardly from the wall around the window casing while the front panel extends between the lateral panels as recognized in valance design.
As is apparent from the above description, the production of bottom rails and valances can be quite labor intensive. Such intensiveness is due in part at least to the fact that both the bottom rail and the valance must be prepared with adequate precision so that pull cords have properly placed openings in the bottom rail and that valance panels are properly angled at their meeting sites and correctly sized so that they can be effectively applied at the top of window blind units. Accordingly, a primary object of the present invention is to provide a machine for efficiently forming a bottom rail and a valance for a window blind unit.
Another object of the present invention is to provide such a machine wherein the bottom rail is cut to size and in which a bored portion and an accompanying drilled portion is provided for entry and anchoring of pull cords.
Yet another object of the present invention is to provide such a machine wherein valance components are cut to size and angled at appropriate lateral edges for generally precise meeting at perpendicular edges.
These and other objects of the present invention will become apparent throughout the description thereof which now follows. | {
"pile_set_name": "USPTO Backgrounds"
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In the field of microwave and millimeter wave energy transmission, such as commercial automotive radar systems (e.g. DE/Delphi's 77 GHz Forward Looking Radar), a myriad of microwave or millimeter wave components are involved, including millimeter integrated circuits (MMICs), diodes, printed circuits, antennas, and possibly waveguide components such as voltage-controlled oscillators (VCOs) and isolators. Most of the components utilized are typically mounted on planar microstrip transmission line circuits since this method is extremely low cost. However some components, such as antennas, may be more preferably compatible with waveguide transmission lines instead of microstrip transmission lines. Therefore, when microstrip transmission lines are used in conjunction with waveguide transmission lines, there is a need for an effective way to transfer transmitted wave energy between the microstrip transmission line and the waveguide transmission line without serious return loss and insertion loss degradation.
One method of designing microstrip to waveguide transitions is to use probes to couple energy to and from the waveguide. However, at very high frequencies (such as 77 GHz) probes are very tiny and difficult to handle in a high volume manufacturing environment. Manufacturing tolerance errors can cause serious return loss and insertion loss degradation.
For example, one prior art coupling technique is known as a probe launch. A circuit board (e.g., a DUROID.TM. board) is cut back so that a tab having a microstrip transmission line which runs to the end of the tab, is inserted into the waveguide. The typical circuit board ground plane is cut away below the microstrip transmission line protruding into the waveguide so that the insulator portion of the board supports the "stick out" tab portion of the microstrip transmission line as a probe. The cutaway circuit board is placed into a waveguide opening, thereby creating a probe launch into the waveguide. However, the difficulty with such an approach is the ability to manufacture and assemble the components in a high volume manufacturing environment. It is somewhat difficult to cut the circuit board to make the microstrip probe and then slip the cut board into the waveguide structure such that there is good contact between the ground of the circuit board and the waveguide wall. Also, it should be noted that the waveguide opening where the circuit board is inserted must be carefully controlled so that the probe does not short circuit against the waveguide wall. As such, those skilled in the art can appreciate that the whole manufacturing and assembly procedure involved with providing a mechanically and electrically stable microstrip probe end launch is not straightforward.
Another similar probe launch technique also involves a microstrip transmission line on a circuit board (e.g. a DUROID.TM. board), where at an end point along the microstrip transmission line there are a series of vias in a rectangular pattern around the end point and through the circuit board and connecting with the typical circuit board ground plane. The rectangular pattern of vias conduct all the way to the ground plane. A waveguide back short then connects with the vias at the ground plane and waveguide walls are formed perpendicular to the duroid board at the end point so that a microstrip to waveguide transition is formed. This approach allows such end launching to be formed in the middle of a board rather than at the end as described previously with the cut board and "stick out" tab probe. This approach also requires having a sizeable opening in the waveguide which can produce unwanted leakage radiation. While this latter approach may be somewhat simpler to accomplish than the former cut board approach, similar manufacturing control problems as previously described still exist.
There is therefore still a need for an efficient, cost effective method and apparatus for coupling microwave or millimeter wave frequency range energy from a microstrip transmission line to a waveguide transmission line. The present invention provides such a microstrip to waveguide transition whose simple assembly makes it ideal for high volume manufacturing. | {
"pile_set_name": "USPTO Backgrounds"
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The present invention is directed generally to coupling assemblies for coupling a wristworn device to a strap, and in particular, to a sleeve that is designed to fit over a spring bar, conventional or otherwise, and facilitate the removal and attachment of the strap to the wristworn device. In a preferred embodiment, the wristworn device is a wristwatch but as will be understood from the disclosure herein, the invention is not so limiting.
Constructions that attempt to facilitate a user's ability to couple and decouple the wristwatch to/from the strap are well known. For example, one known solution has spring bars where a pin is radially fixed on one of the two axially movable spring-loaded pins and the radial pin protrudes through a slot of the tube of the spring bar. The watchband/strap has a longitudinal slot allowing the radial pin of the spring bar to protrude and allow for manual movement within the longitudinal slot of the strap until the strap can be disassembled from the watchcase. Some other prior art constructions are described in U.S. Pat. Nos. 1,194,484; 2,870,511; 2,901,806; 3,824,783; 4,285,450; 4,564,308; 5,483,505 and 6,647,593. However, all of the foregoing constructions have perceived deficiencies.
It is thus believed that further advances to the state of the art are both desirable and achievable. In particular, it is desirable to provide users with an ability to more easily couple and decouple a strap to and from a wearable device, such as wristwatch by way of example. Accordingly, constructions and methodologies for attachment in accordance with the present invention are set forth herein. | {
"pile_set_name": "USPTO Backgrounds"
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This invention relates to a crankshaft assembly composed of a pair of crankshafts each having a crank arm formed with an opening for a crankpin to be force fitted and secured therein and a crank web disposed in a position diametrically opposed to that of the crank arm and an intermediate crank arm formed at opposite end portions thereof with the crankpins each force fitted and secured in one of the openings at the crank arms, and more particularly it is concerned with a crankshaft assembly of the type described which is suitable for use with a two-cylinder, two-cycle internal combustion engine wherein fuel-air mixture is supplied from a carburetor to a crankcase and pressure is applied thereto.
In a crankshaft assembly of the type described of the prior art, the assembling of the parts is performed as follows. A crankpin formed at one end of the intermediate crank arm is force fitted and secured in an opening formed in the crank arm of one crankshaft to provide a sub-assembly, and a crankpin formed at an opposite end of the intermediate crank arm of the sub-assembly is force fitted and secured in an opening formed in the crank arm of the other crankshaft, to provide a complete assembly.
In producing the crankshaft assembly of the aforesaid type, it has hitherto been usual practice to insert, when the operation of assembling the parts is performed, a plate-like jig in a clearance between the crank web of the crankshaft and the intermediate crank arm of the sub-assembly so that the jig will bear pressure which is applied to the other crankpin to force fit same in the opening formed in the crank arm of the other crankshaft, to thereby prevent excessive pressure from being applied to the crankshaft of the sub-assembly. In the internal combustion engine of the type described hereinabove, it is necessary to minimize the dead space in the crankcase to improve engine efficiency by increasing the primary compression pressure of the fuel-air mixture. To this end, the clearance between the crankshaft and the intermediate crank arm is made as small as possible. This makes it imperative to use a jig of a small thickness for insertion in the clearance of a small size. Thus, the crankshaft assembly of the type described of the prior art has had the problem that the jig itself might undergo deformation when a crankpin force fitting operation is performed, resulting in the crankshaft and intermediate crank arm being out of alignment with each other and adversely affecting the crankshaft sub-assembly. | {
"pile_set_name": "USPTO Backgrounds"
} |
Although many electrolyzers are based on an alkaline (KOH) electrolyte, another option is to use a proton exchange membrane (PEM) as the electrolyte. In PEM electrolysis, water is supplied to the anode and is split into oxygen, protons and electrons by applying a DC voltage. Protons pass through the polymer electrolyte membrane and combine with electrons at the cathode to form hydrogen; thus oxygen is produced at the anode, and hydrogen is produced at the cathode as illustrated in a schematic diagram in FIG. 1. It is important that the hydrogen and oxygen, which evolve at the surfaces of the respective electrodes, are kept separate and do not mix.
The electrolysis process is essentially the reverse of the process in a PEM fuel cell. A PEM electrolyzer cell can be very similar in structure to a PEM fuel cell, with a polymer membrane sandwiched between a pair of porous electrodes and flow field plates. FIG. 2A shows a simplified diagram of an electrolyzer unit cell, and FIG. 2B shows a simplified diagram of a fuel cell unit cell. The materials used in a PEM electrolyzer are generally different because the carbon materials commonly used as catalyst supports, gas diffusion layers and flow field plates in fuel cells cannot be used on the oxygen side of a PEM electrolyzer due to corrosion. Metallic components (for example, tantalum, niobium, titanium, or stainless steel plated with such metals) are often used instead for porous layers and flow field plates in PEM electrolyzers. The catalyst is typically platinum or a platinum alloy, and is designed to operate in the presence of liquid water.
Multiple electrolyzer cells can be connected either in series or in parallel (to get the desired output at a reasonable stack voltage) to form an electrolyzer stack. In addition to one or more electrolyzer stacks comprising end plates, bus plates and manifolds, and other system components, an electrolyzer system will typically comprise a power supply, a voltage regulator, water purification and supply equipment including a circulation pump, water-gas separators for hydrogen and optionally oxygen, a thermal management system, controls and instrumentation, and equipment for storage and subsequent dispensing of the product gas(es).
A fuel cell system can be combined with an electrolyzer system, so that a renewable energy source can be used to power an electrolyzer to generate hydrogen and oxygen which can be stored, and then subsequently used as reactants for a fuel cell to produce electric power. Such a combined electrolyzer/fuel cell system is illustrated in FIG. 3A. Efforts are presently underway to develop a unitized stack that could serve as both fuel cell and electrolyzer. Such a device has been referred to as a “reversible fuel cell” or a “unitized regenerative fuel cell” (URFC). A PEM URFC stack delivers power when operated as a fuel cell using hydrogen as the fuel, and either air or oxygen as the oxidant, and generates hydrogen and oxygen when operated as an electrolysis cell. A URFC system is illustrated in FIG. 3B.
Design of the individual cells and cell components for a URFC should address the distinctly different operating conditions occurring during each mode of operation. For example, the oxygen/air electrode potential is quite different in one mode versus the other. In the exothermic fuel cell mode, humidified, gaseous reactants are generally required along with rapid removal of the heat and water produced, while in the electrolysis mode, liquid water is required as the reactant at one electrode, with rapid removal of the product oxygen at the anode and hydrogen at the cathode. The balance of plant supporting the PEM URFC is designed to handle product water in the fuel cell mode, maintain the thermal balance within the fuel cell (cooling plates are typically used to remove excess heat when the fuel cell is producing power), deliver clean reactants, and produce regulated power. Balance of plant issues for URFC include design of the thermal management system (because operation in the electrolysis mode is slightly endothermic), and collection of the product hydrogen and optionally oxygen.
In a PEM electrolyzer the issues associated with liquid reactant supply and gaseous product removal are somewhat different to those in a PEM fuel cell, where hydrogen and a gaseous oxidant (for example, air) are typically supplied to the anode and cathode respectively, and water is produced at the cathode. In PEM fuel cells the gaseous reactants are generally supplied to the electrodes via channels formed in the flow field plates. A typical reactant fluid flow field plate has at least one channel through which a reactant stream flows. The fluid flow field is typically integrated with the separator plate by locating a plurality of open-faced channels on one or both faces of the separator plate. The open-faced channels face an electrode, where the reactants are electrochemically converted. In a single cell arrangement, separator plates are provided on each of the anode and cathode sides. In a stack, bipolar plates are generally used between adjacent cells; these bipolar plates generally have flow fields on both sides of the plate. The plates act as current collectors and provide structural support for the electrodes.
The flow field used at both the anode and the cathode can have an important influence on fuel cell performance, and much work has been done on the optimization of flow field designs for PEM fuel cells. Conventionally the reactant flow channels in fuel cell flow fields have a constant cross-section along their length. However, U.S. Pat. No. 6,686,082 (which is hereby incorporated by reference herein in its entirety) describes fuel cell embodiments in which the fuel flow channels have a cross-sectional area that decreases linearly in the flow direction. For fuel cells operating on air as the oxidant, as the air flows along the cathode flow channel(s), the oxygen content in the air stream tends to be depleted and the air pressure tends to drop, resulting in reduced performance in the fuel cell. U.S. Pat. No. 7,838,169 (which is hereby incorporated by reference herein in its entirety) describes improved cathode flow field channels that can be used to achieve substantially constant oxygen availability along the channel.
Less work appears to have been done on studying the effect of flow field design on the performance of PEM electrolyzers, although it has been reported that electrolyzer operation is generally less sensitive to changes in flow field design than fuel cell operation.
It has been reported (Hwang, C. M., et al. Abst. #1405 Honolulu PRiME 2012, The Electrochemical Society) that in a PEM URFC, a preferred flow field design for operation in the fuel cell mode does not work so well in electrolysis mode, particularly at higher current densities (where the rate of hydrogen and oxygen production is greater). The study notes that serpentine flow fields are popular for PEM fuel cells because gas flow in a serpentine flow field has a higher velocity and greater shear force providing efficient removal of product water in the channels. Contrary to this, in electrolysis mode the longer serpentine flow field channels can be disadvantageous because product gases (hydrogen and oxygen) can tend to accumulate in the channels and hinder the supply of water to the electrode, and limit the rate of electrochemical oxidation of reactant water.
Although flow fields that are preferred for fuel cells are not necessarily the same as those that are preferred for electrolyzers, the Applicants have discovered that flow fields where the channel cross-sectional area varies along the length of the channel, particularly at the oxygen electrode, can offer advantages in electrolyzers, as well as in URFCs that can operate in both fuel cell and electrolyzer modes. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
The present invention relates to an oven controlled crystal oscillator for high stability, using a thermostat (hereunder, “highly stable oscillator”), and particularly relates to a highly stable oscillator which is effective in heat utilization.
2. Description of the Related Art
In this kind of crystal oscillator, the operating temperature of the crystal resonator is maintained constant by an oven controlled using a thermostat so as to increase the frequency stability. For example, it has been used for base stations for optical communication. Recently, miniaturization has spread even to industrial crystal oscillators, requiring corresponding miniaturization.
FIG. 7 is diagrams for explaining an example of a conventional crystal oscillator, FIG. 7A being a fragmentary vertical sectional view of a highly stable oscillator, and FIG. 7B being a conceptual diagram showing a procedure for inserting a crystal resonator into a thermostat.
As shown in FIG. 7A, this highly stable oscillator comprises a crystal resonator 2, an oven controlled by a thermostat (hereunder, “thermostat”) 3 which accommodates the crystal resonator 2, and oscillating elements 4 and temperature control elements 5, which are all mounted on a first circuit board 1a and a second circuit board 1b. The first circuit board 1a is supported by metallic pins 7a serving as external terminals which are insulated from and pierce a metallic base 6. The second circuit board 1b is supported by metallic pins 7b placed on the first circuit board 1a. In addition, thermostat 3 is supported by a leg 7c with the second circuit board 1b.
As shown in FIG. 7B, the crystal resonator 2 is sealed in a resonator container 9 composed of a metallic case out of which is led a pair of lead wires 8 for, for example, an AT cut or an SC cut crystal piece. The thermostat 3 comprises a heating coil 11 coiled around the periphery of a thermostat mainframe (metallic cylinder) 10 which accommodates the crystal resonator 2 therein. Alternatively, the heating coil 11 may be coiled directly around the resonator container 9 of the crystal resonator 2. The thermostat 3 is arranged in the center of one principal plane of the second circuit board 1b and adhered to the second circuit board 1b by an adhesive 12.
Particularly in the case where the crystal resonator 2 is vacuum sealed, the temperature of the crystal piece is determined by the radiant heat from the resonator container 9. Therefore the heat capacity is reduced compared to the case where a gas is additionally sealed in. On the other hand, if the thermostat mainframe 10 is used, the heat capacity is increased by the thermostat mainframe 10 itself. Therefore there is no oversensitive response with respect to rapid temperature variations, enabling prevention of momentary fluctuations in the oscillating frequency, and an increase in the stability. However, the starting characteristics of the crystal resonator are reduced. Moreover, in the case where the heating coil is coiled directly around the resonator container 9, then for example if the subsequently sealed crystal resonator 2 has some defect, the heating coil 11 and the like must also be discarded. However, if the thermostat mainframe 10 is used, only the defective crystal resonator 2 need be exchanged, which is economically convenient.
The oscillating elements 4 constitute an oscillation circuit together with the crystal resonator 2, and are arranged on the other principal plane of the second circuit board 1b. The temperature control elements 5 also contain at least a thermistor 5a as the temperature sensitive element, and together with a transistor constitutes a temperature control circuit which controls the temperature of the thermostat 3. The members except for the thermistor 5a are arranged on the outside surface of the first circuit board 1a. The temperature control circuit detects the temperature inside the thermostat 3 by joining the thermistor 5a to the thermostat 3 for example. Then, based on the detected temperature, the power to be supplied to the heating coil 11 is controlled to maintain the temperature inside the thermostat 3 constant. The first and the second circuit boards 1a and 1b, the crystal resonator 2 and the like are covered with a metallic cover 17.
According to such a construction, the operating temperature of the crystal resonator 2 can be kept constant by the thermostat 3, enabling prevention of frequency fluctuations of the oscillation frequency due to temperature variations. In other words, fluctuations in the oscillating frequency based on the frequency temperature characteristics of the crystal resonator 2 can be prevented. Moreover, since the second circuit board 1b mounted with the oscillating elements 4 is arranged on the thermostat 3, frequency fluctuations due to the temperature characteristic of the circuit element itself can be prevented.
Therefore, such a crystal oscillator is employed particularly for industrial crystal oscillators where, by increasing the frequency stability, for example the frequency deviation can be made 0.05 ppm or less.
Moreover, in the conventional crystal oscillator as shown in FIG. 7A, the second circuit board 1b is mounted with the oscillating elements 4 and electrically connected to the first circuit board 1a by the metallic pins 7b, and the metallic pins 7a of the first circuit board 1a are led out as the external terminals. Therefore, the metallic pins 7b of the second circuit board 1b are not led out directly to the outside, enabling prevention of heat release to the outside.
However, in the conventional highly stable oscillator having the above construction, the second circuit board 1b is jointed onto the thermostat 3 by the adhesive 12. Accordingly, the heat from the heating coil 11 of the thermostat 3 is blocked by this adhesive 12, so that the thermal efficiency with respect to the oscillating elements 4 on the second circuit board 1b is impaired. The general adhesive 12 is poor in pyroconductivity.
Moreover, even if a thermo-conductive adhesive 12 is applied, it is difficult to control the thickness of the adhesive 12, thus generating an uneven coating, so that the heat distribution of the second circuit board 1b becomes unstable. Furthermore, after the metallic cover 17 is covered over the thermostat 3, convection occurs inside the cover 17, which generates temperature variations in the oscillating elements 4 on the second circuit board 1b. Particularly, together with the thermo-sensor (thermistor 5a), for example a voltage variable capacitative element as the highly temperature dependent highly heat sensitive element is directly affected, so that its characteristics are reduced. Furthermore, the thermostat 3 is manufactured by coiling the heating coil 11 around the thermostat mainframe 10. Hence manufacturing costs are increased. | {
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This invention relates to a one-piece fishing lure and more particularly to an artificial fishing lure including a unitary piece of sheet stock having sections thereof angularly related relative to each other in a new and novel manner.
It is an object of the present invention to provide an artificial fishing lure which exhibits a new and novel action as it is moved through water.
It is another object of the present invention to provide a fishing lure having a one-piece body which has sections thereof angularly relative to each other in a new and novel manner.
Yet another object of the present invention is to provide a fishing lure comprising a one-piece body of sheet stock having a central sheet section integrally mounting, along one lateral edge thereof, longitudinally disposed front and rear flanges which extend transversely to the plane of the central sheet section and which are disposed on the same side of the plane of the central sheet section.
Still another object of the present invention is to provide a one-piece fishing lure of the type described including a central sheet section mounting, along one lateral edge thereof, longitudinally disposed flanges disposed at different angles relative to the plane of the central sheet section.
Other objects and advantages of the present invention will become apparent to those of ordinary skill in the art as the description thereof proceeds. | {
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1. Field of the Invention
The present invention relates to a four-wheel drive device capable of optionally setting the torque distribution ratio to the front wheels and the rear wheels.
2. Related Art Statement
Hitherto, it has been possible to drive a front-wheel drive vehicle straight ahead on a road more safely than a rear-wheel drive vehicle. However, a front-wheel drive vehicle cannot be made to easily turn a corner since a driver must continue to maintain the tire in a position which enables the vehicle to completely turn the corner against the urge of the tire to return to the original straight ahead position. On the contrary, it is possible to make the rear-wheel drive vehicle easily turn a corner. However, it has a problem in that the vehicle of this type easily slips on a slippery road.
Accordingly, there has been disclosed a four-wheel drive device capable of distributing the driving force to the front wheels and the rear wheels so that the vehicle is operated by the driving force thus distributed. However, the four-wheel drive device encounters a problem in that the vehicle is brought to a braking state due to the difference in rotational speed between the front wheels and the rear wheels when the vehicle is rapidly turned at low speed on a road having a large friction coefficient, that is, a tight-corner braking phenomenon is undesirably generated.
In order to overcome the above-described problem, a central differential gear device is provided so as to absorb the difference in the rotational between the front wheels and the rear wheels. That is, in the above-described four-wheel drive device, the rotation of the engine is first devided by the central differential gear device so as to be transmitted to a differential gear device for the front wheels and that for the rear wheels via the propeller shaft.
However, in the conventional four-wheel drive device, torque transmitted from the transmission portion thereof is enlarged by a reduction device before it is transmitted to the transfer portion.
That is, the output shaft of the transmission portion is connected to the input shaft of the transfer portion via the reduction gear so that the torque transmitted from the transmission portion is supplied to the central differential gear device after its level has been changed by the reduction gear.
In this case, the strength of the above-described differential gear device connected to the reduction gear is determined depending upon the level of the torque obtainable from the reduction gear. Therefore, the size of the central differential gear device must be enlarged so as to correspond to a large-capacity engine. As a result, a problem arises in that the size and the weight of the transfer portion cannot be reduced.
Accordingly, an object of the present invention is to provide a four-wheel drive device capable of enlarging the torque transmitted from a transmission and reducing the size and the weight of the transfer portion. | {
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The present invention relates to the measurement of gas or liquid flow, and more particularly, but not exclusively, to a flow meter apparatus, for measurement of substance (say gas or liquid) flow through a conduit.
The measurement of liquid or gas flow under pressure in enclosed pipes has historically been performed through the use of mechanical flow meters.
Typically, in the mechanical flow meters, a first mechanism has moving parts which move upon interaction with a gas or a fluid flowing through a pipe, and the movement of the parts is mechanically transmitted to moving parts of a second mechanism used to register the amount of water or gas flowing through the pipe.
For example, piston meters, also known as rotary piston or semi-positive displacement meters, operate on the principle of a piston rotating within a chamber of known volume. For each rotation, an amount of water passes through the piston chamber. As the piston rotates, a needle dial and an odometer type display are advanced.
A turbine flow meter translates the mechanical action of the turbine rotating in a liquid flow around an axis into a user-readable rate of flow.
The turbine's wheel is set in the path of a fluid stream. The flowing fluid impinges the wheel's blades, imparting a force to the blades surfaces and setting the wheel in motion. When a steady rotation speed is reached, the rotation speed is proportional to fluid velocity.
Turbine flow meters are used for the measurement of both gas and liquid flow.
With turbine meters, the flow direction is generally straight through the meter, allowing for higher flow rates and less pressure loss than displacement-type meters.
Turbine meters have become the meters of choice for large commercial users, fire protection, and as master meters for water distribution systems.
A woltmann meter comprises a rotor with helical blades inserted axially in the flow, much like a ducted fan. Woltmann meters may be considered a type of turbine flow meter. Woltmann meters are commonly referred to as helix meters, and are popular at larger sizes.
A nutating disk meter is probably the most commonly used meter for measuring water supply.
With a nutating disk meter, the substance, most commonly water, enters in one side of the meter and strikes a nutating disk, which is eccentrically mounted. The disk must then nutate about the vertical axis, since the bottom and the top of the disk remain in contact with a mounting chamber. A partition separates the inlet and outlet chambers. As the disk nutates, it gives direct indication of the volume of the liquid that has passed through the meter as volumetric flow is indicated by a gearing and register arrangement, which is connected to the disk.
Some mechanical flow meters are rather pressure-based.
Pressure-based flow meters typically rely on Bernoulli's principle, either by measuring the differential pressure within a constriction, or by measuring static and stagnation pressures to derive the dynamic pressure.
For example, a Venturi meter constricts the flow in some fashion, and pressure sensors measure the differential pressure before and within the constriction. This method is widely used to measure flow rate in the transmission of gas through pipelines, and has been used since Roman Empire times.
Optical flow meters use light to determine flow rate.
In one example, small particles which accompany natural and industrial gases pass through two laser beams focused in a pipe by illuminating optics. Laser light is scattered when a particle crosses the first beam. The detecting optics collects scattered light on a photo detector, which then generates a pulse signal. If the same particle crosses the second beam, the detecting optics collect scattered light on a second photo detector, which converts the incoming light into a second electrical pulse. By measuring the time interval between the two pulses, the gas velocity may be calculated.
Another currently used flow meter is a magnetic flow meter in which a magnetic field is applied to a metering tube, which results in a potential difference proportional to the flow velocity perpendicular to the flux lines. The physical principle at work is Faraday's law of electromagnetic induction. The magnetic flow meter requires a conducting fluid, e.g. water, and an electrical insulating pipe surface, e.g. a rubber lined nonmagnetic steel tube.
Ultrasonic flow meters measure the difference of transit time of ultrasonic pulses propagating in and against flow direction. This time difference is a measure for the average velocity of the fluid along the path of the ultrasonic beam. By using the absolute transit times both the averaged fluid velocity and the speed of sound can be calculated, as known in the art. | {
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Foodstuff grinders utilize one or more blades and a perforated screen to comminute a feed material, that is, to reduce the size of pieces making up the feed material. The apparatus forces the feed material against the screen with sufficient force to cause portions of the material to enter the screen openings. The blades of the apparatus are driven across the screen openings periodically to cut off that portion of the material having entered the respective screen opening. This relatively small piece of material may then be displaced through the screen opening as the apparatus presses additional feed material against the perforated screen. The severed pieces of material are eventually ejected from an outlet end of the respective screen opening.
Most foodstuff grinders use either a flat plate screen with a substantially planar cutting surface, or a drum-shaped screen having a generally frustoconical inside surface making up the cutting surface. In flat-plate grinders, the blades usually extend generally transversely to an axis extending perpendicularly through a center point of the grinding plate. The transverse extending blades are connected to a drive shaft and pass over the screen openings of the flat plate to provide the desired cutting action as the drive shaft rotates about the perpendicular center axis of the plate. Grinders that have a frustoconical screen employ an auger that rotates about the longitudinal axis of the screen. The outside edge of the auger acts as a blade that passes over the screen openings periodically as the auger rotates.
In addition to grinding or further comminuting a feed material, some grinders are capable of separating out pieces of hard material that are included in the feed material. Pieces of bone, connective tissue, and sinew, are commonly included in a mass of comminuted meat that is to be further ground or sized through a grinding device. Pieces of this type of hard material that are too big to pass through the grinder screen openings are forced into a separate outlet of the grinder. However, small pieces of hard material are commonly chipped off or otherwise separated from larger pieces as the larger pieces are pressed against the grinder screen and as the blades continually move over the screen openings. Some of these chipped or otherwise separated pieces of hard material may be small enough to pass through the screen openings, and thus some pieces of hard material may be included with the meat at the grinding device output. This inclusion of small hard pieces of material in the final comminuted meat product is highly undesirable. | {
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A wide variety of intracorporeal medical devices have been developed for medical use, for example, intravascular use. Some of these devices include guidewires, catheters, medical device delivery systems (e.g., for stents, grafts, replacement valves, etc.), and the like. These devices are manufactured by any one of a variety of different manufacturing methods and may be used according to any one of a variety of methods. Of the known medical devices and methods, each has certain advantages and disadvantages. There is an ongoing need to provide alternative medical devices as well as alternative methods for manufacturing and using medical devices. | {
"pile_set_name": "USPTO Backgrounds"
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Spinal pathologies and disorders such as scoliosis and other curvature abnormalities, kyphosis, degenerative disc disease, disc herniation, osteoporosis, spondylolisthesis, stenosis, tumor, and fracture may result from factors including trauma, disease and degenerative conditions caused by injury and aging. Spinal disorders typically result in symptoms including deformity, pain, nerve damage, and partial or complete loss of mobility.
Non-surgical treatments, such as medication, rehabilitation and exercise can be effective, however, may fail to relieve the symptoms associated with these disorders. Surgical treatment of these spinal disorders includes fusion, fixation, corpectomy, discectomy, laminectomy and implantable prosthetics. For example, fusion and fixation treatments may be performed that employ implants to restore the mechanical support function of vertebrae. Surgical instruments are employed, for example, to prepare tissue surfaces for disposal of the implants. Surgical instruments are also employed to engage implants for disposal with the tissue surfaces at a surgical site. This disclosure describes an improvement over these prior technologies. | {
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1. Field of the Invention
The present disclosure relates generally to memory fault testing, and more specifically to a system and method for identifying address-swap faults in multiport memories.
2. Description of the Related Art
An address “mis-decode” fault occurs when an address applied to a memory accesses a different memory location, that is, a location that is not the addressed location. An address-swap occurs when a first address ends up accessing a location of a second address, and the second address ends up accessing a location of the first address. Address mis-decode faults occur due to various defects on the address bus, such as stuck-at faults, shorts and opens. Address-swap faults occur, however, when there is an inversion fault, or when two bits of an address bus are swapped due to a design implementation error or because of faulty wiring. Defects such as shorts and opens can result in inversion faults. An inversion fault occurs when defects in a circuit result in a logic net flipping to the opposite value (e.g., actual value on a logic net is logic “1” but is flipped or inverted to a logic “0” and vice-versa).
Bit-swap faults and inversion faults were not considered an interesting class of faults for logic circuits because they are implicitly detected by conventional and existing test routines employing common fault models such as the stuck-at fault model. Bit-swap and inversion faults are undetectable for single-port memories. Such faults were considered inconsequential for single-port memories since as long as a data value is correctly stored using an address value (even if at a different location) and is correctly read out using the same address value, the single-port memory operates as intended. Bit-swap and inversion faults, however, may cause chip failure for multiport memory devices and further may be undetectable. In the case of multiport memory devices, a fault at one port causes read and/or write errors at other ports and vice-versa. Conventional test procedures or routines were unable to detect such address-swap faults in multiport memory devices. | {
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A significant amount of effort has been focused on improving user experience with respect to visual displays in the home environment. For example, a significant amount of research and advancement has occurred with respect to visual quality of traditional displays (e.g., such as televisions and computer monitors), and also with respect to opportunistically leveraging other displays that happened to be in the environment (e.g. “stitching” multiple displays together to make a larger display, moving visual content across multiple displays, etc.). Enhancing an audio experience of the user, however, has lagged behind.
Referring to audio systems in general, while the electronics that generate sounds can have a relatively strong effect on soundscapes and the listening experience, room design and environmental acoustics strongly impact perceived audio quality. One technique for enhancing audio quality output by an audio system is to customize the design of a room in which the audio system will be utilized. This frequently occurs in movie theaters, auditoriums, and the like. Other types of rooms, however, such as classrooms, living rooms, etc., are typically not designed to take into consideration acoustic properties.
An exemplary approach used in connection with some audio systems is to attempt to model acoustic properties of a room utilizing a calibration signal and corresponding microphone. Typically, a user will arrange a set of speakers in a room and locate herself in a position where she will typically be listening to audio output by the audio system. The user is additionally provided with a microphone, and the audio system outputs a calibration signal when the user is at the location where she typically will listen to the audio produced by the audio system. The calibration signal typically includes sounds in all frequency bands supported by the audio system. Audio captured by the microphone is subsequently analyzed to compute a frequency response for the audio system (based upon the location of the microphone). An equalizer of the audio system is then updated based upon the computed frequency response, thereby taking into consideration impact of the environment on audio output by the audio system.
There are several deficiencies associated with this approach. First, the calibration is static—that is, if furniture is rearranged in the room that includes the audio system, the equalizer will no longer be properly calibrated. Second, the equalizer is not calibrated for all positions in the room. Thus, if the user positions herself in a position in the room that is different from her position when the equalizer was calibrated, the listener will be provided with sub-optimal audio. | {
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The present invention relates to a silver halide emulsion containing silver halide tabular grains having a high silver chloride content (hereinafter referred to as a high silver chloride tabular grains) and having {111} planes as principal planes. Further, the present invention relates to both a color photographic light-sensitive material and an image formation method, using the emulsion. Particularly, the present invention relates to a monodisperse, high-speed, and hard gradation (high contrast) emulsion that is excellent in grain shape stability; and to both a color photographic light-sensitive material and an image formation method (particularly, an image formation method that utilizes of a high illumination intensity and short time exposure), using the emulsion.
As a method for forming tabular silver halide emulsion grains having {111} major planes, for example, U.S. Pat. Nos. 4,400,463, 5,185,239, and 5,176,991, JP-A-63-213836 (the term xe2x80x9cJP-Axe2x80x9d as used herein means an xe2x80x9cunexamined published Japanese patent applicationxe2x80x9d), and U.S. Pat. Nos. 5,176,992 and 5,691,128, disclose a method of forming grains in the presence of crystal habit-controlling agents, i.e. amino azaindenes, triaminopyrimidines, hydroxyaminoazines, thioureas, xanthonoides, and pyridinium salts, respectively.
It is well known in the art that high silver chloride grains originally have a characteristic that selectively {100} planes are apt to come out, and consequently the grains that are ordinarily formed are cubic. In the foregoing patents/publications, with utilizing a crystal habit-controlling agent, tabular grains are formed so that originally unstable {111} planes come out on the grain surface. Therefore, the moment desorption of the crystal habit-controlling agent from the grain surface is occurred, high silver chloride {111} tabular grains are redissolved, and {100} planes arise on the grain surface, so that it is difficult to maintain the grain shape. Further, it is difficult to expect to attain high sensitivity by spectral and chemical sensitization, without desorption of the crystal habit-controlling agent from the grains.
U.S. Pat. No. 5,691,128 discloses that the strength of adsorption of a crystal habit-controlling agent is controlled by pH-regulation, and exchange adsorption is made between a sensitizing dye and the crystal habit-controlling agent, thereby achieving compatibility between stabilization of the grain shape and enhancement of sensitivity.
Further, U.S. Pat. No. 5,272,052 discloses that composite grains composed of host grains and epitaxial portions (epitaxies) can be formed by epitaxially growing silver bromide selectively at the apexes (corners) of a grains by means of adsorption of a crystal habit-controlling agent, which is then replaced on the tabular grain surface by exchange adsorption of a photographically useful compound.
However, these epitaxial grains were also insufficient for a practical use, because during or after the spectral and chemical sensitization, these grains momentarily changed the adsorption state of dyes and the grain shapes, when they were in a condition where a crystal habit-controlling agent had been desorbed from the grains. Especially, the halogen composition of the epitaxial portion was unstable.
An object of the present invention is to provide a silver halide emulsion that is excellent in grain shape stability of {111} tabular grains, and that is a monodisperse, high-speed, and high contrast emulsion, and moreover that is able to concurrently improve both high illumination intensity reciprocity law failure and latent-image stability after exposure to light. Further, another object of the present invention is to provide a high-speed, and high contrast color photographic light-sensitive material that is able to concurrently improve both high illumination intensity reciprocity law failure and latent-image stability after exposure to light. Further, another object of the present invention is to provide an image formation method that is able to exert photographic characteristics of the above-described emulsion or light-sensitive material even when they are subjected to a rapid processing by means of a scanning exposure and so on.
Other and further objects, features, and advantages of the invention will appear more fully from the following description, taken in connection with the accompanying drawings. | {
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In some wireless communication systems, it may be useful to determine positions of wireless communication devices. Some techniques for determining positions of wireless communication devices involve determining distances between communication devices, and using distance measurements to calculate positions of the devices. A distance between two device can be determined by transmitting a signal from one device to another, determining the time it took for the signal to travel between the two devices (time of flight), and then calculating the distance between the two devices based on the time of flight. | {
"pile_set_name": "USPTO Backgrounds"
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I. Field
The present disclosure relates generally to communication, and more specifically to techniques for allocating resources in a wireless communication system.
II. Background
Wireless communication systems are widely deployed to provide various communication services such as voice, video, packet data, messaging, broadcast, etc. These systems may be multiple-access systems capable of supporting multiple users by sharing the available system resources. Examples of such multiple-access systems include Code Division Multiple Access (CDMA) systems, Time Division Multiple Access (TDMA) systems, Frequency Division Multiple Access (FDMA) systems, Orthogonal FDMA (OFDMA) systems, and Single-Carrier FDMA (SC-FDMA) systems.
A wireless communication system may include a number of Node Bs that can support communication for a number of user equipments (UEs). A UE may communicate with a Node B via the downlink and uplink. The downlink (or forward link) refers to the communication link from the Node B to the UE, and the uplink (or reverse link) refers to the communication link from the UE to the Node B.
A UE may be intermittently active and may operate in (i) an active state to actively exchange data with a Node B or (ii) an inactive state when there is no data to send or receive. The UE may transition from the inactive state to the active state whenever there is data to send and may be assigned resources for a high-speed channel to send the data. However, the state transition may incur signaling overhead and may also delay transmission of data. It is desirable to reduce the amount of signaling in order to improve system efficiency and reduce delay. | {
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Methods according to the present invention are generally useful for studying kinase activity in situ and for screening molecules that modulate kinase activities in situ.
Optimal drug design largely depends upon drug specificity in the complex context of a living cell. Anti-tumor chemotherapeutic drugs, for example, ideally destroy malignant cells while having a minimal damaging effect on healthy cells. However, most chemotherapeutic drugs have limited specificity and are toxic to both normal and malignant cells. Examples of such side-effects on healthy cells include direct myocardial damage, heart rhythm disturbances, pericarditis, pulmonary fibrosis, hemorrhage, nausea, vomiting, dyspnea, alopecia, peripheral and central neuropathies, pain, nephropathies, stomatitis, diarrhea, fever, immunosuppression, and changes in the state of consciousness. Therefore, cytotoxic side-effects of these chemotherapeutics greatly limit their efficacy.
Many cytostatic drugs, including those used in chemotherapy, function by inducing programmed cell death (apoptosis). However, since many tumor cells arise because of failure to respond to natural cues for apoptosis, they tend to be resistant to chemotherapeutic drugs that aim at triggering apoptotic cues. Therefore, a key strategy of the pharmaceutical industry for treating tumor cell growth is to pre-sensitize cells to apoptotic cues. A means for doing this is to block the protein kinases that inhibit apoptosis, thereby either directly inducing cell death or sensitizing cells to other anti-tumor drugs. Such kinases include the survival kinases AKT, IKK, ERK, Raf-1, PI 3-kinase, PDK-1 and others. Up-regulation of these kinases blocks apoptosis, and is often associated with tumors in humans and other mammals, further suggesting that identification and inhibition of these kinases will be of therapeutic benefit, (e.g., by enhancing the apoptosis-inducing effects of current anti-tumor therapeutics). There is also much interest in finding molecules that inhibit kinases that control other cell functions such as inflammation signaling, cell growth, and cell metabolism. Such inhibitors need to be highly selective in targeting specific kinases in situ.
Presently, most kinase activity measurements are carried out on recombinant proteins, produced and purified from insect cells or from mammalian cells in culture. In vitro assays such as radiometric assays or in-plate binding assays with read-outs are then used to measure the activity of these purified kinases. These in vitro assays are performed under conditions that only marginally reproduce the context of a live cell and are likely to have only marginal biological relevance. Therefore, even when a drug molecule is identified based on its in vitro specificity for a particular kinase, the in situ or in vivo specificity of the molecule remains extremely difficult to assess. Drugs developed using in vitro assays often turn out to have little or no effect in vivo or to have highly toxic side effects such as those mentioned above.
Realizing the importance of examining biological activities inside cells, the pharmaceutical industry is moving towards cell-based screens. However, developing a whole cell screening assay that monitors kinase activity, e.g., in response to an inhibitory molecule, is particularly difficult because of the large number of different kinases within the cell and because of the structural similarities of the catalytic regions of many of these kinases. One approach has been to look at fixed cell imaging of activated kinases. However, this approach only measures whether a kinase has been phosphorylated by an upstream activator kinase. Other approaches rely on a reporting system that is hard to duplicate for multiple kinases, such as the use of fluorescence resonance energy transfer (FRET) technology, which examines an isolated protein-protein interaction that is regulated by a kinase. Because these assays evaluate only a single kinase at a time, they have limited utility for purpose of drug discovery. Further, reporter systems such as FRET are not easily amenable to high-throughput or multiplexing approaches often needed in today""s drug discovery programs.
There is, therefore, a need for an in situ kinase assay that determines kinase specificity within a living cell. In particular, an assay is needed that provides information on multiple protein kinases simultaneously, and that provides real-time determination of kinase specificity.
The present invention provides kinase assays that are cell-based, and that allow for the discovery of compounds capable of modulating kinase activity in situ. It is an object of the invention to provide methods that can be adapted to assay the activities of different kinases in a cell with relative ease. It is a further object of the invention to provide methods that can screen a candidate molecule, e.g., a small molecule, peptide or drug candidate, regarding its ability to modulate multiple kinases simultaneously. The invention also provides compounds and molecules identified through these methods.
In a preferred embodiment, these and other objects of the invention are accomplished by providing assays based on a cellular signaling event between a signaling enzyme and its substrate. One example of such a signaling event is the binding between the signaling enzyme ubiquitin E3 (E3) ligase, and its substrate. After the binding, the E3 substrate is subject to transubiquitination and targeted by the degradation pathway. Another example of a signaling event on which the invention may be based is part of a peptide translocation pathway. Specifically, the signaling event can be the binding of a transporting protein to a traffic signaling domain of its substrate. After binding takes place, the substrate is eventually transported from a first subcellular area to a second area.
According to the invention, either the signaling enzyme or its substrate is altered so that their interaction is regulated by a kinase of interest. A label is associated with the signaling substrate so that the kinase activity of interest is monitored through the expression of the label as the signaling pathway now targets both the substrate and the label, for example, by degrading or transporting the substrate and the label. Because the signaling pathway takes place in a living cell, monitoring of the kinase activity through the label expression is carried out in situ. When a cell is exposed to a candidate molecule, changes in the expression of the label are indicative of whether the candidate molecule modulates the kinase activity of interest. Because the assay is conducted in live cells, results from the assay provide reliable and relevant information on biological functions and drug specificity.
According to one aspect of the invention, a signaling substrate is altered. In one embodiment, the kinase recognition domain of signaling substrate is modified. For example, an adapter module, e.g., a consensus recognition motif for a kinase of interest, is incorporated into a wild type kinase recognition domain. Alternatively, random mutagenesis can be performed on the wild type kinase recognition domain to produce specificity for the kinase of interest, which can be verified through subsequent screening. Through one or both of the above methods of modification, binding between the altered signaling substrate and the signaling enzyme becomes regulated by the kinase of interest. Using recombinant DNA technologies, an adapter module can be easily incorporated into a peptide. Because the consensus recognition motifs for many kinases are known, methods of the invention generally provide assay systems that can be routinely modified to test large numbers of kinases. These kinases include, but are not limited to, survival kinases implicated in apoptosis, thereby allowing discovery of drugs such as those that can be used in anti-tumor therapies. In an embodiment, a signaling substrate is altered such that its enzyme binding region is flanked by two sequestering motifs that interact with each other. The interaction between the sequestering motifs prevents the signaling substrate from being recognized or bound by the signaling enzyme. The interaction between the sequestering motifs is regulated by a kinase of interest. As a result, binding between the altered signaling substrate and the signaling enzyme is also regulated by the kinase of interest.
In an exemplary method, a candidate molecule is exposed to a cell that expresses a phosphorylation substrate having a kinase recognition domain. The kinase recognition domain is altered to be recognized by a kinase of interest that does not recognize the substrate in its unaltered state. A detectable label is associated with the phosphorylation substrate. This method of the invention further includes determining whether the candidate molecule causes a change in the expression of the label in order to identify a molecule that is capable of modulating the activity of the kinase of interest in situ.
In one embodiment of the invention, the phosphorylation substrate is also the substrate for an E3 ligase. In its unaltered state, binding of the phosphorylation substrate to the E3 ligase is regulated by a wild type kinase, and after the binding takes place, the substrate is eventually degraded by the proteosome. Methods of the invention provide various ways of altering the phosphorylation substrate so that binding between E3 and the substrate, and the ensuing ubiquitin-mediated degradation of the substrate are preserved and regulated by at least one kinase of interest that normally does not regulate the E3 binding event. A label is associated with the substrate, allowing monitoring of E3 binding and providing a readout as a consequence of the cell""s exposure to a candidate molecule.
In another embodiment of the invention, the phosphorylation substrate is also the substrate for a transporting protein that causes the substrate to be translocated from a first subcellular area to a second are. In its unaltered state, the phosphorylation substrate""s binding with the transporting protein is regulated by a wild type kinase, e.g., through an allosteric modification that affects the structural conformation of the phosphorylation substrate. The modification may change the accessibility by a transporting protein to different traffic signaling regions on the substrate. Binding of the transporting protein to a different signaling region results in translocation of the substrate to a different subcellular area, such as mitochondria, endoplasmic reticulum (ER) or the extracellular space. Methods of the invention provide various ways of altering the phosphorylation substrate such that binding between the transporting protein and the substrate, and the ensuing translocation of the substrate, are preserved and regulated by at least one kinase of interest that normally does not regulate the binding event. A label is similarly associated with the substrate for allowing monitoring the signaling event and any modulation of the signaling event due to cellular exposure to a candidate molecule.
In another embodiment according to the first aspect of the invention, a candidate molecule is exposed to a cell that expresses a signaling substrate whose enzyme binding region is flanked on both sides by two sequestering motifs. When the pair of sequestering motif interact with each other, they prevent the enzyme binding region from binding with the signaling enzyme, for example, because of conformational changes to the substrate. The interaction between the sequestering motifs is regulated by a phosphorylation event that a kinase of interest is responsible for. A detectable label is associated with the signaling substrate and by determining whether the candidate molecule changes the expression of the label in the cell, a molecule capable of modulating the activity of the kinase of interest in situ can be identified. Examples of the signaling substrate include those for an E3 ligase involved in a ubiquitin-mediated degradation pathway, and those for a transporting protein involved in a peptide translocation pathway.
According to another aspect of the invention, the signaling enzyme is altered. In one embodiment, an adapter module, whose ability to recognize and bind to its ligand is regulated by a kinase of interest, is incorporated into the signaling enzyme. Through the adapter module, the altered signaling enzyme becomes capable of recognizing and binding the ligand of the adapter module, subject to regulation by the kinase of interest. In another embodiment, random mutagenesis is performed on a portion of the signaling enzyme, preferably the substrate-binding portion, so that the mutant enzyme recognizes and binds a phosphorylation substrate having a particular phosphorylation state.
In one embodiment, a candidate molecule is exposed to a cell that expresses a signaling enzyme that is altered to bind a phosphorylation substrate for a kinase of interest that, in its unaltered state, the signaling enzyme does not bind. A detectable label is associated with the phosphorylation substrate. Further, binding between the altered signaling enzyme and the substrate is regulated by a kinase. This method of the invention further includes determining whether the candidate molecule causes a change in the expression of the label in order to identify a molecule that is capable of modulating the kinase activity in situ. Examples of the signaling enzyme include an E3 ligase involved in a ubiquitin-mediated degradation pathway, and a transporting protein involved in a peptide translocation pathway.
According to another aspect of the invention, assays according to any of the above-described embodiments of the invention are multiplexed to study multiple kinases by using differentiable labels that are each associated with a different kinase substrate. For example, multiple phosphorylation substrates may each be mutated to contain a kinase recognition domain for a different kinase, each substrate associated with a differentiable label. Examples of such labels include GFP and its variants, which fluoresce at differentiable wavelengths. Expressing these multiple kinase substrates in one of the cell-based assay systems described above allows monitoring of kinase regulation of a signaling event and any modulation thereof by a candidate molecule to which the cell is exposed. An application of the multiplexed embodiment is the screening for a molecule for specificity for multiple kinases in the same signaling pathway.
The invention also provides molecules identified through one of the methods described wherein the molecule is capable of modulating a kinase activity in situ. The invention also provides fusion proteins useful for the methods described, isolated genetic molecules encoding the fusion proteins, vectors capable of expressing the genetic molecules, and cells transfected with at least one of such vectors. | {
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1. Field of the Invention
This invention relates to the recovery of nitramines from aluminized energetic materials. This invention is particularly useful for recovering nitramines from aluminized energetic materials such as solid propellants, explosives, and pyrotechnics.
2. Description of the Related Art
Energetic materials have found widespread use, perhaps no more extensively than in military applications, where energetic materials are used to make composite propellants for ballistic missiles and explosive compositions for munitions and ordnances. An example of a propellant commonly found in rocket motors and missiles is Class 1.1 solid propellants. Like most other energetic materials used in military applications, Class 1.1 solid propellants are formed from a composition comprising a combination of one or more of the following: polymeric binders, plasticizers, ballistic additives, chemical stabilizers, curing agents and catalysts, metal powders, and inorganic and/or organic oxidizers.
Demilitarization in the United States and abroad has created a need for an economical, reliable, non-hazardous, and environmentally friendly method for disposing of the stockpile of surplus tactical missiles and explosives existing worldwide. Additionally, a growing number of larger rocket motors, such as intercontinental ballistic missiles (ICBMs), are being and will have to be demilitarized due to international treaties, such as the START treaties. The disposal of such energetic materials is the subject of various publications and U.S. patents, including U.S. Pat. No. 4,231,822 to Roth and U.S. Pat. No. 4,661,179 to Hunter et al. However, these U.S. patents focus on disposing of explosive materials by xe2x80x9cdesensitizingxe2x80x9d or xe2x80x9cdestroyingxe2x80x9d the materials.
The degradation of energetic materials into an unusable state is not the most economical alternative of disposal, since many energetic materials are both expensive and reusable. For example, one class of organic oxidizer that has found wide acceptance in the rocket propulsion, explosive, and pyrotechnic arts comprises nitramines. Common nitramines include, for example, cyclotetramethylenetetranitramine (also known as HMX and 1,3,5,7-tetranitro-1,3,5,7-tetraaza-cyclooctane), cyclotrimethylenetrinitramine (also known as RDX and 1,3,5-trinitro-1,3,5-triaza-cyclohexane), TEX (4,10-dinitro-2,6,8,12-tetraoxa-4,10-diazatetracyclo-[5.5.0.05,903,11]-dodecane), HNIW (also known as CL-20) (2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazatetracyclo [5.5.0.05,903,11]-dodecane), and combinations thereof. Nitramines are commonly among the most expensive and highly energetic ingredients of conventional energetic compositions. Further, nitramines are sometimes present in energetic compositions in relatively high concentrations, such as on the order of up to about 50% by weight of solid rocket motor propellants and up to about 98% by weight of explosives. These factors make the successful and efficient recovery of nitramines in high yields for subsequent re-use highly desirable.
A method for the extraction and recovery of nitramine oxidizers from solid propellants is disclosed in U.S. Pat. No. 5,284,995 to Melvin, which discloses the use of a liquid ammonia extraction agent for extracting the nitramines HMX and RDX from rocket motor solid propellants. The use of liquid ammonia in nitramine recovery techniques introduces several complexities and expenses, especially in a closed system, including high capital expenditures required as outlay to obtain equipment capable of operating at the high-pressures (5 to 40 Kpsi) at which liquid ammonia is handled. The presence of liquid ammonia also creates other problems, such as worker safety issues, since contact between the ammonia and human skin can cause severe chemical burns to the handler. Additionally, liquid ammonia is combustible, and presents a severe inhalation hazard if not handled correctly. Another disadvantage of the U.S. Pat. No. 5,284,995 process is that subjecting energetic materials, such as Class 1.1 propellants containing nitramine oxidizers, to the pressurized environments described in the ""995 patent increases the risk of accidental detonation, as well as the accompanying catastrophic consequences that an accidental detonation or explosion often has on human life and property. Yet another disadvantage of the process of U.S. Pat. No. 5,284,995 is that nitramines are dissolved in liquid ammonia, requiring recrystallization of the nitramines. However, the recrystallized nitramines have different particle sizes than the nitramine particles found in the propellant. Also, if recrystallization is not performed under the right conditions, the polymorph of the nitramine changes during recrystallization.
Another method for recovering ingredients from a pyrotechnic material is disclosed in U.S. Pat. No. 4,098,627 to Tompa et al., in which the pyrotechnic containing a cured polymeric binder is decomposed under mild conditions. The method involves heating the pyrotechnic material to a temperature of from about 50xc2x0 C. to about 160xc2x0 C. in a liquid medium comprising an active hydrogen-containing compound capable of cleaving the chemical bonds contained in the polymer. Representative liquid media include mineral acids such as hydrochloric acid, sulfuric acid, phosphoric acid, nitric acid and perchloric acid, as well as primary amines, secondary amines, ammonia, and water. The process is expedited by modifying the liquid medium via the addition of an organic solvent. Organic solvents reportedly suitable in the process are toluene, xylene, dioxane, and tetrahydrofuran. The organic solvent functions either to swell the organic polymeric binder present in the pyrotechnic material or to dissolve filler material present in the pyrotechnic material. The decomposition technique is carried out at 80xc2x0 to 120xc2x0 C. In practice, however, these organic solvents raise a host of ecological and safety concerns, including flammability, VOC emissions, environmentally sound and cost-effective waste disposal, and handling expenses. Additionally, U.S. Pat. No. 4,389,265 to Tompa et al. reports that the use of mineral acids and water in the manner prescribed by the ""627 patent produces low yields of about 36%. Indeed, example 5 of the ""627 patent reports that under the basic conditions of its process RDX may be destroyed.
Two additional approaches for reclaiming nitramines from propellants having polymeric binders are disclosed in U.S. Pat. No. 4,389,265 to Tompa et al. The first approach utilizes a solution of 2-aminoethanol in a mixture of an aromatic solvent and an alcohol to dissolve the propellant binder. The 2-aminoethanol breaks down or dissolves the polymeric binder. Examples of aromatic solvents suitable for the first approach include benzene, toluene, xylene, ethylbenzene, and diethylbenzene. Examples of alcohols suitable for the first approach include ethanol, 1-propanol, 2-propanol, and mixtures thereof. The second approach is performed with a solution of a mineral acid other than nitric acid, an organic solvent, and water. For the second approach, examples of suitable mineral acids are hydrochloric, sulfuric and phosphoric acid; examples of organic solvents are acetone, methylethylketone, tetrahydrofuran, and mixtures thereof. The mineral acid and organic solvent combine to break down or dissolve the polymeric binder. After dissolution of the pyrotechnic binder is completed in the 2-aminoethanol or the mineral acid process, the nitramine and metals, if present, are removed by filtration and the nitramine is extracted in acetone. Although relatively high yields are reported in U.S. Pat. No. 4,389,265, the presence of aromatic and organic solvents raises ecological and safety concerns over such issues as flammability, volatile emissions, and waste disposal. Also, the nitramine is recovered with aluminum fuel particulates. Consequently, separation of the aluminum requires dissolving, filtering, and recrystallizing of the nitramine. As mentioned above, recrystallization can cause the polymorph and size of the nitramine particles to change.
U.S. Pat. No. 6,063,960 discloses the recovery of nitroamines and reformulation of by-products. The ""960 patent generally focuses on non-aluminized propellants, with the exception of its mention of VTG-5A and WAY, both of which are aluminized propellants. According to the ""960 patent, the propellants are treated with 60-70% nitric acid in a preferred ratio of nitric acid solution to feed of 1.0:1.0 l/kg. This feed ratio calculates to a weight ratio of less than 1.5:1. Although these conditions are adequate to recover nitramines from non-aluminized propellants containing conventional binders, in the case of an aluminized propellant a substantial proportion of aluminum would not be dissolved under these conditions. Accordingly, in the event that an aluminized propellant were treated by the ""960 process, separation of the aluminum would require additional steps of dissolving, filtering, and recrystallizing of the nitramine.
Thus, it would be a significant improvement in the art to develop a method in which nitramines are recovered from aluminized energetic materials without recrystallizing the nitramines and in which there is no need for the use of either liquid ammonia under increased pressure or hazardous organic solvents that are volatile and/or flammable.
It is, therefore, an object of the present invention to fulfill a long-felt need in the art by providing a nitramine-recovery process capable of achieving the above-discussed improvements in the recovery of nitramines from aluminized energetic materials, especially aluminized propellants, without relying upon either the use of liquid ammonia under increased pressures or the application of hazardous solvents.
In accordance with the principles of this invention, the above and other objects are attained by a nitramine-recovery process in which a nitramine-containing aluminized energetic material is treated with aqueous nitric acid having a nitric acid concentration of not more than 55% by weight. This low concentration nitric acid, when used in appropriate ratios relative to the aluminized energetic material to be treated, has the effect of digesting by solvation and/or solvolysis most, if not all, conventional ingredients other than nitramines commonly found in aluminized energetic materials. As referred to herein, the term solvation means the dissolving of a solid into a solvent without chemical reaction. As also referred to herein, the term solvolysis means the dissolving of a solid into a solvent via chemical reaction between the solid and solvent.
At least one mineral acid other than nitric acid is added to the digestion process in order to facilitate digestion of the aluminum. It is also preferred to delay the addition of the mineral acid until sufficient time has passed for the aqueous nitric acid to digest most, if not substantially all, of the binder of the energetic material. The time needed for digesting the binder will depend upon several factors, including the amount of binder in the energetic material, the concentration and amount of aqueous nitric acid, and process conditions, such as temperature. Suitable mineral acids include hydrochloric acid, perchloric acid, sulfuric acid, phosphoric acid, hydrobromic acid, hydroiodic acid. Hydrochloric acid is currently preferred because of its high rate of aluminum digestion. Representative concentrations of mineral acid for use in the aluminum digestion range, for example, from about 1 part by weight to about 5 parts by weight based on 100 parts by weight of the aqueous nitric acid. Such concentrations are usually sufficient to digest at least 99 weight percent of the aluminum. Aqueous nitric acid is preferably not selected as the mineral acid for aluminum digestion. Nitric acid is relatively oxidizing compared to other mineral acids, and will oxide the surface of the aluminum to form aluminum oxide, thereby slowing the rate at which the aluminum is digested.
The nitramines remain substantially insoluble (i.e., are neither solvated nor solvolyzed) in the low concentration nitric acid and mineral acid, and can be separated from the aqueous nitric acid, mineral acid, and digested ingredients in an efficient manner and without incurring great expense.
The recovered nitramines according to the presently preferred embodiment are suitable for recycling into an energetic material, including a solid propellant grain, explosive material, and pyrotechnics (known in the art as PEP materials).
There are several advantages that can be derived from the inventive process. For example, nitramine yields associated with embodiments of the present invention have been found to be much higher than most conventional processes. In particular, nitramine yields are routinely on the order of 90% by weight or greater according to embodiments of the inventive process. Further, the process can be performed, and preferably is performed, free of organic solvents, thus avoiding the ecological and safety concerns and waste disposal and handling expenses of conventional processes. Furthermore, the digested ingredients separated from the nitramine can be recovered and reused as feed stock for commercial blasting agents, thus further reducing the waste disposal concerns and improving the efficiency of the process. The process also does not require volatile digestion agents or high pressurizes that increase the risk of un intentional detonation of the energetic material.
The recovery method of this invention is particularly useful for recovering nitramines from aluminized energetic materials such as solid propellants, explosives, and pyrotechnics, and is especially useful for the recovery of nitramines from aluminized solid rocket motor propellants. While not wishing to be bound by any theory, it is believed that unlike many conventional methods, in which nitramines are typically dissolved in order to separate the nitramines from aluminum and/or other ingredients, in the present invention the aluminum reacts with aqueous nitric acid to form aluminum nitrate Al(NO3)3.9H2O, which is soluble in the aqueous nitric acid and the mineral acid is easily separated from the substantially insoluble nitramine. Additionally, unlike other inorganic acids that react with aluminum to rapidly generate large amounts of hydrogen gas and high temperatures, nitric acid has been found to undergo a much more sedate reaction with aluminum. The reaction of nitric acid with aluminum generates hydrogen gas and heat at manageable rates so as to permit the hydrogen gas and heat to be removed from the digestion vessel. By adding a mineral acid, other than nitric acid, aluminum removal is facilitated and accelerated. | {
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The present invention relates generally to the field of shared computer communications and computer conferencing. In particular, one embodiment of a conferencing system according to the present invention facilitates the conferencing of two or more persons, each with a computer at one or more locations with a shared visual display and additional communication capabilities such as video, shared drawing, audio, text chat, etc., and facilitates the recording and later playback of the communications.
Existing conferencing systems can be described as either video conferencing systems or “whiteboard” systems. In a video conferencing system, a snap-shot of the conference presentation is taken at regular intervals, such as thirty times per second. Given that the image on a computer display is not changing nearly that often, video conferencing wastes large amounts of bandwidth. In a whiteboard system, the presenter at the conference draws within a whiteboard application or imports the output of another program into the whiteboard program for manipulation. When the presenter is ready to present a snap-shot, the presenter presses a “send” button and the whiteboard program updates all the attendees' displays with the image created by the presenter. This type of system, while requiring less bandwidth than video conferencing, is clumsy to use, lacks real-time responses, and limits the presenter to the tools provided with the whiteboard program.
Existing shared-display or shared-image systems rely on interception and communication of display or graphics system commands or depend on-conferees' having similar hardware and software platforms. These systems lack flexibility and performance if the network connections are unreliable or have narrow bandwidth, or they require uniform hardware or software installations.
Existing systems that provide single or multiple data stream handling of a nature different than shared-image conferencing depend on wide bandwidth network connections or on all participants having similar platforms. | {
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In the case of converting light from an emitting medium to light containing a component having a longer wavelength light ray, there is generally used a color conversion layer (fluorescent medium layer) which absorbs light (for example, light in a blue range) from the fluorescent medium and emits fluorescence having a longer wavelength.
At this time, the color conversion cannot be effectively attained since the light from the emitting medium is not sufficiently absorbed by the color conversion layer and the fluorescence therefrom is hindered from being taken outside because of self-absorption of the fluorescent medium in the color conversion layer.
Incidentally, a structure wherein light-scattering particles are dispersed into a color conversion layer has been investigated. As a result, it is disclosed that the lifetime of a color conversion filter is improved (see, for example, Japanese Patent Application Laid-open No. 2002-216962).
However, more efficient color conversion cannot be attained only by dispersing light-scattering particles into a color converting layer.
A fluorescent material in a color conversion layer may interact with light-scattering particles to cause extinction of fluorescence, or the color conversion efficiency thereof may be lowered with the passage of time by light from an emitting medium.
Accordingly, it has been desired to make clear a physical range in which color conversion can be more efficiently attained and thus develop a color conversion layer which exhibits only a small deterioration with the passage of time. | {
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The present invention relates to a force plate comprising a plate-shaped carrier which, when arranged vertically, has an upper carrier section at the top in the vertical direction and a lower carrier section at the bottom in the vertical direction, wherein at least one first end carrier section is provided and is connected, at one side, to the upper carrier section via a vertical rod and, at another side, to the lower carrier section via a horizontally arranged spring element that is provided with strain gauges.
DE 28 13 769 A1, which corresponds to U.S. Pat. No. 4,125,168, discloses a force plate which, together with a second force plate, forms an electronic balance. The known force plate comprises a plate-shaped carrier which is arranged vertically and has an upper carrier section at the top and a lower carrier section at the bottom, wherein, at least at one end side of the force plate, a first end carrier section is provided and is connected, at one side, to the upper carrier section by a vertical rod and, at another side, to the lower carrier section via a horizontally arranged spring element that is provided with strain gauges.
A disadvantage of the known force plate is that further horizontal bending webs or bending rods are provided above and below, arranged parallel to the horizontally arranged spring element that is provided with strain gauges. These bending webs/rods also connect the end carrier section to a further carrier section and are intended to eliminate the effect of disruptive shear forces on the spring element. This results in a force plate which is relatively complex and therefore difficult to produce.
DE 25 43 354 A1, which corresponds to U.S. Pat. No. 3,951,221, discloses a force plate, the upper carrier section of which is connected via a vertical rod to a horizontal spring element that is provided with a strain gauge. | {
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Currently available mirror and television devices typically include a television mounted to the back of a mirror. This arrangement is a convenient space saving device as it embeds a television in the existing space occupied by a mirror. Although available, these devices typically suffer from either poor transmissivity or reflectivity.
The transmissivity and reflectivity of a mirror are roughly inversely related. That is, a mirror with high transmissivity generally has low reflectivity, and a mirror with high reflectivity generally has low transmissivity. As a result, a mirror with high transmissivity will allow more light from a television located behind the mirror to pass through the mirror, resulting in better viewing of the image displayed on the television. However, such a mirror will also have a relatively low reflectivity, resulting in a lower quality reflection in the mirror.
In addition to the presenting the difficulty of balancing television image quality with the reflection quality, current mirror/television combinations do not provide additional sources of illumination, such as back lighting. This results in the need for separate light fixtures in addition to the mirror/television combination, which can cause additional installation costs and unsightly clutter. | {
"pile_set_name": "USPTO Backgrounds"
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Field
The disclosure relates generally to a buck voltage regulator and, more particularly, to a buck voltage converter operating in pulse frequency modulation (PFM) mode thereof.
Description of the Related Art
Voltage regulation is important where circuits are sensitive to transients, noise and other types of disturbances. The control of the regulated voltage over variations in both semiconductor process variation, and temperature is key to many applications. Additionally, the noise generation from switching noise emissions from inductors can impact sensitive circuitry and lead to system level issues in real systems, and applications. Electromagnetic interference (EMI) is a growing concern in electronic components and systems.
EMI is a concern in voltage converter circuitry for buck, boost, and buck-boost converters, and more particularly for circuitry operating in pulse frequency modulation (PFM) mode. The PFM mode of operation is commonly used in “sleep mode” in direct current-to-direct current (DC-to-DC) converters. Buck converters can operate in two modes, known as pulse frequency modulation (PFM) mode, and pulse width modulation (PWM) mode. The PFM mode is typically used for low load currents. In a buck converter output driver stage, there is typically a p-channel metal oxide semiconductor (PMOS) transistor pull-up device, and an n-channel metal oxide semiconductor (NMOS) transistor pull-down device. In PFM mode of operation, the buck converter turns on the PMOS transistor when the output voltage falls below the digital-to-analog converter (DAC) voltage. In the buck converter, the PMOS transistor is then turned off when the current in the inductor coil reaches a threshold value (e.g., the “sleep current limit”). The NMOS is turned on when the PMOS is turned off. The NMOS is then turned off when the current in the coil is fully discharged. PFM is not typically used for large currents as the current limit is normally set low to maximize efficiency.
FIG. 1 shows a circuit schematic block diagram of a buck control system for pulse frequency mode (PFM) sleep mode. The buck 100 is composed of a power supply VDD 101, and ground VSS 102. The output driver stage comprises a PMOS pull-up transistor 105 and NMOS pull-down transistor 110. The PMOS transistor 105 has a gate driver 115 and the NMOS transistor 110 has a gate driver 120. The gate drivers are driven by a control logic block 125 which receives signals Vunder 126 and Ilimit 127. The output stage of the PMOS transistor 105 and the NMOS transistor 110 provides current to inductor Lout 150, with the current sensed by sense circuit 130. The sense circuit 130 provides a feedback signal line 132 for the Ilimit signal flag 127, based on a current limit reference Ilimitref provided by current source 135. Voltage LX 140 connected at the input to inductor Lout 150, connected to output capacitor 155 and output signal Vout 160. The output of the pass devices 105 and 110 are connected directly to the LX node 140. The sense block detects the current flowing through the LX; this outputs a scaled replica of this output current to the reference current source 135. If the sensed current is higher than the reference current, the voltage at node 132 will fly high and be detected by the control block 125. The output signal Vout 160 is connected to the feedback loop 165 configured to provide the signal Vfb 171 to comparator 170. A digital-to-analog converter (DAC) 175 is configured to provide a signal Vdac 173 to the comparator 170. When the output voltage falls below the DAC voltage 173 the Vunder signal 126 is raised. This turns on the PMOS transistor 105 which charges up the current in the inductor coil 150: When the inductor coil current reaches the current limit, the Ilimit flag 127 is raised. This turns off the PMOS transistor 105 and turns on the NMOS transistor 110. Once the inductor coil current reaches zero, the NMOS transistor 110 turns off, and the output goes high-impedance. The cycle is started again once the output voltage again falls below the DAC voltage 173.
FIG. 2 shows the timing diagram 200 for the signals for this mode of operation. The feedback voltage Vfb 210 and digital-to-analog converter output voltage Vdac 220 are overlaid in the timing diagram 200. The comparator output signal Vunder 230 is shown below highlighting the transistions associated with the comparator input signals. FIG. 2 shows the p-channel MOS (PMOS) gate signal Pgate 240, n-channel MOS (NMOS) gate signal Ngate 250 as well as the current limit signal Ilimit 260 and inductor coil current Icoil 270.
The feedback voltage Vfb 171 is equal to the output voltage of the buck converter 160. As this falls below the digital-to-analog converter (DAC) voltage Vdac 173 the under-voltage signal Vunder 126 turns on. This leads to the turn on of the PMOS gate (active low), which causes the inductor coil current to increase. Once this reaches the current limit, the PMOS 105 turns off and the NMOS 110 turns on. The inductor coil current then discharges. Once this is fully discharged, the NMOS 110 is turned off. The output voltage 160 then discharges with the applied load until the feedback voltage Vfb 171 once again falls below the DAC voltage Vdac 173.
As the load increases so the frequency with which the buck converter switches also increases. The frequency of the buck converter can vary from very low frequencies (less than 1 Hz) up to the maximum frequency of the buck converter, determined by minimum on time and minimum off time. This can be typically around 5 MHz.
The change in current in the coil of the buck tends to emit noise which is picked up by surrounding circuits. This noise can be the source of issues within real systems and applications. Electromagnetic interference (EMI) can lead to both soft failures and hard failure. Soft failures can include timing impact, false signals, and system disturbs. Hard failure can be damage to internal devices or components that are destructive.
U. S. Patent Application 2014011 1174 to Shtargot et al describes a switching regulator with a split inductor for reduction of electromagnetic interference (EMI).
U.S Patent Application 20130051089 to Pan et al., describes a frequency jittering control circuit for a PFM power supply includes a pulse frequency modulator to generate a frequency jittering control signal to switch a power switch to generate an output voltage. The frequency jittering control circuit jitters an input signal or an on-time or off-time of the pulse frequency modulator to jitter the switching frequency of the power switch to thereby improve EMI issue.
U.S. Pat. No. 7,893,663 to Ng, describes a method and apparatus for active power factor correction with sensing the line voltage. This utilizes a power factor correction apparatus which uses Pulse Frequency Modulation (PFM) to control an AC/DC converter. The switching frequency varies with the line voltage such that the converter emulates a resistive load. By using PFM control, EMI is spread over a range rather than concentrated at a few frequencies.
U.S. Pat. No. 6,204,649 to Roman describes using a switching regulator for reducing electromagnetic interference (EMI) includes a PWM controller which incorporates a varying frequency oscillator for controlling the operating frequency of the switching regulator.
In these prior art embodiments, the solution to establish a switching regulator with reduced EMI utilized various alternative solutions. | {
"pile_set_name": "USPTO Backgrounds"
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Garments that are worn for formal occasions may be rented as rental attire. Garments of this type are subjected to high material stresses on account of numerous care treatments. In particular, repeated final processing by dry cleaning results in high material stresses. As a result, after a short time these garments can no longer be worn at formal occasions because they have a used, worn-out appearance.
The referenced garments may be men's suits, which include pants, vests, sport coats, or blazers. Such garments may also be dress suits for women or girls.
For this reason, for several years there has been a need by ready-to-wear manufacturers and service providers in the rental attire industry for garments that withstand the stresses of commercial laundries under the conditions of DIN/ISO Standard “Commercial Laundering and Finishing Processes for Testing Work Clothes” (DIN ISO 15797:2004).
In order to withstand the treatment in commercial laundries with as little damage as possible, the garments must have very good washing resistance at temperatures of up to 95° C. The garments must also be able to withstand extreme drying conditions of up to 150° C. in a tunnel finisher under high numbers of operating cycles. Up to 50 cycles may be performed.
The garments known from the prior art are seldom, if ever, washable. At best, the known garments may be laundered at 30° C. in a gentle wash cycle in a home appliance, although loss of shape must be accepted. For this reason rental attire is usually dry cleaned, i.e., chemically cleaned, which is expensive, harmful to the environment, and effective only to a limited extent. In addition, complex drying and pressing operations are necessary to restore the shape of the garment. Furthermore, the known garments have only a limited lifetime, and their care is also very costly. | {
"pile_set_name": "USPTO Backgrounds"
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This invention relates to an engine starter motor for starting an engine and particularly to an engine starter motor having a speed reduction gear between a unidirectional clutch and a pinion gear.
An engine starter motor is known, in which the rotational speed of an electric motor is reduced by one or two stages, an electric motor unit is reduced in size and weight, and in which an unidirectional (over-running) clutch is mounted to a speed-reduced pinion shaft. In the engine starter motor of this structure, the effect of the inertia moment of the electric motor on the unidirectional clutch increases by the square of the speed reduction ratio as it increases. Therefore, a disadvantageously large capacity unidirectional clutch is required for an engine starter motor having no speed-reduction mechanism, in which the rotation of the armature rotary shaft is directly transmited to the unidirectional clutch.
Therefore, there has been proposed an engine starter motor such as disclosed in Japanese Patent Laid-Open No. 52-73315 in which an over-running clutch is disposed on an armature rotary shaft as well as an engine starter motor such as disclosed in Japanese Patent Laid-Open No. 60-2895 in which an over-running clutch is disposed on an idle shaft in order to eliminate the above-discussed disadvantages of the conventional design.
FIG. 1 illustrates the engine starter motor disclosed in Japanese Patent Laid-Open No. 52-73315, in which reference numeral 1 indicates a d.c. motor, 2 indicates an armature of the d.c. motor 1, and 3 indicates an armature rotary shaft. An over-running (unidirectional) clutch 4 is mounted to the armature rotary shaft 3, and a clutch outer member 5 of the over-running clutch 4 is secured to the armature rotary shaft 3 by splines 6 and a clutch inner member 9 having a pinion gear 8 of a speed reduction gear 7 is mounted on the armature rotary shaft 3 rotatable relative to it. Rollers 10 are interposed between the clutch outer member 5 and the clutch inner member 9, and 11 indicates a cover. Reference numeral 12 indicates a larger gear which is in mesh with the pinion gear 8 and which has a pinion shaft 13 centrally engaged through helical splines 14 on the pinion shaft 13. A front end portion of the pinion shaft 13 has mounted thereon a pinion 16 which is enagageable with an engine ring gear 15, and a rear end portion of the pinion shaft 13 has mounted thereto a stopper 17 for positioning the forward position of the pinion shaft 13 and a return spring 18 disposed between the stopper 17 and the large gear 12. A lever 19 transmits a drive force from a plunger 20 of the solenoid.
In the engine starter motor with the above structure, when the plunger 20 is actuated by an electromagnetic attraction, the lever 19 rotates in the clockwise direction as viewed in the figure, the pinion shaft 13 is driven in the forward direction against the spring action of the return spring 18 to cause the pinion 16 to mesh with the engine ring gear 15. Also, the rotation of the armature rotary shaft 3 is transmitted through the unidirectional clutch 4, the smaller gear 8, the larger gear 12, the splines 14 and the pinion shaft 13 to the engine ring gear 15 to start the engine. The torque applied to the unidirectional clutch 4 is the maximum torque generated by the electric motor 1, and the torque at the pinion gear 16 is equal to the torque generated by the electric motor 1 multiplied by the speed reduction ratio between the small gear 8 and the large gear 12. Also, while the effect of the inertia moment of the rotating armature 2 only directly acts on the uni-directional clutch 4 which is directly connected to the armature 2, it acts on the pinion 16 as increased by a factor of the square of the speed reduction ratio.
After the engine is started and the plunger 20 is released, the action of the return spring 18 causes the shift lever 19, the pinion shaft 13 and the pinion 16 to return to their original positions, whereby the operation of the engine starter motor is stopped.
FIG. 2 illustrates an engine starter motor disclosed in Japanese Patent Laid-Open No. 60-2895. In the FIGURE, an idle shaft 21 is disposed on an axis different from those of an armature rotary shaft 3 and a pinion shaft 13, and the unidirectional clutch 4 is rotatably supported on this idle shaft 21. On the outer circumference of the clutch outer member 5 of the unidirectional clutch 4, a speed reducing gear 5a is formed so that it engages a gear 3a formed in the armature rotary shaft 3. Also, a small gear 8 integral with the clutch inner member 9 is in engagement with a large gear 12 formed on a tube 22, thereby forming a speed-reduction gear 7, and the tube 22 and the pinion shaft 13 are spline-engaged to each other through helical splines 14. Reference numerals 23, 24 indicate a housing and a center bearing support, respectively, for supporting the armature rotary shaft 3, the idle shaft 21 and the pinion shaft 13.
Reference numberal 25 indicates a solenoid switch, 26 indicates a plunger of the solenoid switch 25, 27 indicates a rod constructed to move together with the plunger 26, 28 indicates a movable contact, 29 indicates stationary contacts one of which is connected to a battery (not shown) and the other of which is connnected to a d.c. motor 1. Reference numeral 30 indicates a ball interposed between the rod 27 and the pinion shaft 13. In the figure, the same reference numerals used also in FIG. 1 indicate identical or corresponding components, so that their explanation is omitted.
In the engine starter motor as above constructed, the starting operation is achieved in a manner similar to that of the starter shown in FIG. 1, and the transmission torque of the unidirectional clutch 4 equals to the torque of the d.c. motor 1 multiplied by the speed-reduction ratio between the gear 3a and the speed reducing gear 5a, and further even though the effect of the inertia moment of the d.c. motor 1 acting on the unidirectional clutch 4 is increased by a factor of the square of the speed-reduction ratio, this effect is smaller than that where the unidirectional clutch 4 is mounted on the pinion shaft 13.
In the conventional engine starter motor, it has been attempted to reduce the effect of the speed-reduction ratio of the unidirectional clutch 4 and to use the unidirectional clutch 4 in common with the engine starter having no speed reduction gear.
However, since the pinion shaft 13 of the conventional engine starter is engaged with the speed-reduction gear components by the helical splines, a return force is generated on the pinion shaft 13 when the pinion 16 is driven by the engine immediately after the engine is started or when the engine starter motor cannot quickly follow the change in rotation of the engine. That is, when a drag torque which causes the unidirectional clutch 4 to rotate in the idling direction is considered as to the pinion shaft 13, this drag torque is increased by an amount corresponding to the speed-reduction ratio between the unidirectional clutch 4 and the pinion shaft 13. As shown in FIG. 3, the return force F can be expressed by: EQU F=tan (.theta.-.rho.)T/r.sub.H
where,
T: drag torque PA0 r.sub.H : mean diameter of the helical splines 14 PA0 .theta.: twist angle of the helical splines 14 PA0 N: drag PA0 .tau.: friction angle of the helical splines 14. PA0 .alpha.: angle defined between the frictional surfaces of the clutch outer an inner members PA0 .gamma.: angle of direction of a spring force with respect to a tangent at the point of contact of the roller to a frictional surface of clutch inner member PA0 n: number of rollers PA0 r: outer diameter of the clutch inner member PA0 .mu.: friction coefficient of the roller contacting surfaces.
Accordingly, when a unidirectional clutch similar to that of an engine starter with no speed reduction mechanism is used as in the above conventional engine starter, the drag torque as considered from the pinion shaft 13 is increased by an amount corresponding to the speed-reduction ratio and the return force F is also increased accordingly. Therefore, the return force F exceeds the electromagnetic attractive force on the plunger 20 or 26, causing the pinion 16 to return and disengage from the ring gear 15, and if the engine starter motor is being energized at this time and plunger 20 or 26 is being electromagnetically actuated, the pinion 16 is again driven into mesh with the engine ring gear 15. Even when the pinion 16 did not completely disengage from the engine ring gear 15, the pinion 16 moves fiercely, resulting in large mechanical impacts which may destroy or damage the ring gear 15 and other components and generate noise. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field
The present disclosure relates to processors. More particularly, this invention is directed toward a processing of an interrupt collecting and reporting.
2. Description of Related Technology
During a processor's operation, an interrupt may be received at the processor. An interrupt is a signal originated by a hardware or a software entity, which alerts the processor to an event that needs the processor's immediate attention. In response, the processor suspends current operation, saves the state of the operation, and executes an interrupt handler program. After the interrupt handler finishes attending to the interrupt, the processor resumes execution of the interrupted operation.
The interrupt may be received as a change in a level of a signal or a change of an edge of a signal on a wire. The disadvantage of such a solution is a potentially large implementation costs, as a wire is required for each of the hardware or the software entity. Furthermore, generated plurality of interrupts may be written into a wide register with bits for all possible interrupts, or into a tree of such registers; consequently, the processor needs to spend resources and time to search through the wide register or the tree of such registers to determine hardware or a software entity that originated the interrupt.
In another method a software entity, e.g., a kernel, programs a “vector number” into each of the hardware or the software entities originating interrupt(s), and the hardware or the software entity signals via a message, e.g., a Direct Memory Access (DMA) write, when an interrupt occurs. The disadvantage of such a method is an implementation cost because each of the hardware or the software entities needs to store an interrupt number for each vector number, and the programming software entity needs to configure this information. Furthermore, level sensitive interrupts are generally not supported.
Accordingly, there is a need in the art for interrupt collecting an reporting, providing a solution to the above identified problems, as well as additional advantages. | {
"pile_set_name": "USPTO Backgrounds"
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The expression “payment card” is used to designate any bank card with a delayed or immediate debit, any credit card, etc., issued by a bank or a specialised establishment.
The safety of deals made with payment cards is today based on two points: the checking of the signature genuineness as written by the buyer on the invoice, a handwritten or electronic signature, and the checking of the card validity by questioning the establishment who issued the card in order to obtain permission to accept this card.
This double checking is always made by the supplier when he can physically have the payment card. Checking the handwritten or electronic signature is easy, the same applying to the prior authorisation request. There are also card-reading payment terminals that are adapted to execute automatically such checking.
The buyer types on the keyboard of such terminal the secret code for his card, also called PIN code (Personal Identification Number). The electronic circuits then compare the secret code typed by the buyer with the code registered on the card in a cryptic manner and they validate the current deal if they coincide. Also, starting from the data read on the card, the terminal is able to question through a telecommunication network, a management server for payment cards who confirms that the card is valid and not imposed with interdiction. This checking as to the card validity may be made on line by calling the server at the time of the deal, or off line through the regular downloading of lists of forbidden cards (black lists) and/or true card lists (white lists). It should be noted that the use of cards with electronic circuits enables a direct checking of the card genuineness.
Consulting the management servers to find out the status of a payment card and the use of a secret code known only by the card owner considerably reduce the possibility of frauds.
It is not however so when the buyer and the seller are distant one from the other and it is then no more possible to use, to check the card, a payment terminal that reads cards.
As, in order to execute a deal when the buyer and the seller are away from each other, for example when buying by mail, or if a booking is made by phone, or when a deal is executed on the Web, the seller only asks for the card number and the validity date of the buyer's payment card.
Communicating this information alone is sufficient to validate an invoice that the supplier then sends to his bank for payment.
The simplicity of the present mechanism for payment by card for deals executed away is the source of many frauds, as any person knowing the number of a payment card and its validity date may use this information in an illegal manner to buy goods or services and this, as long as the actual card owner is not aware of the misuse caused to him and does not stop payments at the card issuing institution. Also, such system allows improper refusals by dishonest buyers who refuse to have their account debited under the false excuse that the deals were executed unknown to them. This is particularly true for electronic deals executed over Internet, as on such an open communication network, it is rather easy to collect information there exchanged. Such lack of safety is today a strong brake for the Internet trading.
Many tries have been made to eliminate this inconvenience and make the distant deals safer, especially the electronic deals.
Among such tries, there should be mentioned the SET type systems that consist in coding the information exchanged on Internet. With such systems, the bank card numbers are no more openly communicated, and cannot therefore be intercepted. The implementation of such systems is however impaired by the availability for most people of means specifically provided for the safety of deals, such as card readers for computers, coding means in computers or in readers, and standardising the protocols selected by various operators. Also, if numbers can no more be directly intercepted during the communication between the buyer and the Web site, they may still be intercepted on the Web site where the card numbers are stored in a clear manner and they may be intercepted on the computer of the person from spying resident programmes adapted to record information typed by the person on his keyboard.
Another way consists in using a temporary payment card or one with a limited use. Such a card is generally made by the financial institution of the buyer, on his request. This card, the life of which is generally limited for one deal or a given sum of money, is mainly using the same ISO formats as the buyer's main payment card (Visa, Mastercard, etc.)
This solution thus requires the transmission to the buyers, in a secure way, of temporary card numbers. The solution that is generally chosen by the banks consists in using coded SSDL-type connections between the computers of the buyers and the bank servers. This method still has fraud risks, as the methods developed by the cheaters on Internet are more and more performing.
The purpose of this invention is therefore to offer an alternative for transmitting in a confidential way to users the identification data of temporary cards, such as numbers and validity dates, an alternative that should be together safe and easy to operate. | {
"pile_set_name": "USPTO Backgrounds"
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This invention relates to a light-sensitive silver halide color photographic material excellent in tone reproducibility and giving sharp printed images, more particularly to a light-sensitive silver halice color photographic material having high sensitivity, excellent in tone reproducibility and background whiteness, and also giving sharp printed images.
For preventing red saturation phenomenon that delicate light and shade cannot be reproduced at a high density portion of red, as disclosed in Japanese Unexamined Patent Publication No. 68754/1989, there has been known a technique in which a silver halide emulsion in a layer containing a dye-forming coupler is spectrally sensitized to a certain wavelength region, and further spectrally sensitized within a limited range to a wavelength region to which a silver halide emulsion in a layer containing another dye-forming coupler is spectrally sensitized. Further, as disclosed in Japanese Unexamined Patent Publication No. 91657/1986, there has been known a technique in which a dye-forming coupler is contained in a silver halide emulsion spectrally sensitized to a certain wavelength region, and further, a dye of a hue which does not substantially contribute to formation of a hue of said dye-forming coupler is added to have a gradation at a specific density region. However, in these techniques, it is extremely difficult to control contrast without deterioration of color reproducibility, and also sharpness of images has not been discussed at all. | {
"pile_set_name": "USPTO Backgrounds"
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1. Technical Field
The invention relates generally to an apparatus and method for tracking surgical supplies and, more specifically, to counting and accounting for all disposable surgical sponges used in a surgical procedure.
2. Related Art
During surgical procedures, absorbent sponges are employed to soak up blood and other fluids in and around the incision site. In a study entitled “The Retained Surgical Sponge” (Kaiser, et al., The Retained Surgical Sponge, Annals of Surgery, vol. 224, No. 1, pp. 79–84), surgical sponges were found to have been left inside a patient following surgery in 67 of 9729 (0.7%) medical malpractice insurance claims reviewed. In those 67 cases, the mistake was attributed to an incorrect sponge count in seventy-six percent (76%) of the cases studied, and attributed to the fact that no count was performed in ten percent (10%) of the cases studied. Typically, a sponge left inside a patient is presumed to indicate that substandard and negligent care has taken place. Clearly, it is in both a patient's and the health care providers' best interest to account for every surgical sponge used in any particular surgical procedure.
As explained in U.S. Pat. No. 5,923,001 entitled Automatic Surgical Sponge Counter and Blood Loss Determination System, sponge counts are an essential step in operating room procedure. Sponge counts are a difficult procedure for a number of reasons. For example, the handling of soiled sponges carries the risk of transmission of blood borne diseases such as hepatitis B virus (HBV) and human immunodeficiency virus (HIV). Therefore, used sponges are handled with gloves and/or instruments and the handling is kept to a minimum. Another difficulty is that the counting process is typically tedious, time-consuming and frustrating.
Sponge counts are typically performed multiple times during a surgical procedure, both at the beginning and throughout the procedure as sponges are added, before closure of a deep incision or body cavity, and during personnel breaks and shift changes. Thus, within all the activity of an operating room, maintaining an accurate sponge is difficult, as evidenced by the error rate mentioned in the Keiter article, quoted above.
There do exist products to make the procedure both simpler and more reliable. For example, various systems facilitate the hand-counting of surgical sponges by arranging the sponges into visually inspectible groups or arrangements (see U.S. Pat. Nos. 3,948,390, 4,364,490, 4,784,267, 4,832,198, 4,925,048 and 5,658,077). These systems are problematic because surgeons and anesthesiologists often determine blood loss by means of visual inspection or a manual weighing of soiled sponges and so soiled sponges are typically kept in one area of an operating room during a surgical procedure, thus creating the possibility that groupings are co-mingled or counted twice. In addition, operating room workers are often too rushed, fatigued and/or distracted to accurately count a large number of soiled sponges lumped together in one or more groups. This method also depends upon the accuracy of an initial count and, if the number of sponges in the original package is mislabeled by the manufacturer, then a missing sponge may be missed during a final count.
A second solution to the surgical sponge tracking problem is the inclusion of a radiopaque thread in the sponges. A radiopaque thread can be identified and located if a sponge is accidentally left inside a patient. Thus, if a patient develops a problem such as an abscess, a bowel obstruction, or internal pain at any time following an operation, a sponge that has been left in the body can be detected by x-ray. Companies that market sponges with radiopaque threads include Johnson & Johnson, Inc. of New Brunswick, N.J., Medline Industries of Mundelein, Ill. and the Kendall Company of Mansfield, Mass.
A third solution to the sponge problem is the inclusion of a radio frequency identification (RFID) tag in each sponge (see U.S. Pat. No. 5,923,001). The RFID tag enables a patient to be scanned to detect the presence of a sponge within a body cavity, but RFID tags may cost several times what a typical surgical sponge costs and are also bulky, impairing the usefulness of the sponge.
Another solution to the sponge problem is a device that counts sponges as they are dropped, one-by-one, into an opening, or “entry gate,” of the device (see U.S. Pat. No. 5,629,498). This solution is restricted by the accuracy of the original count and the precision of operating room assistants as they separate sponges from one another and drop them into the entry gate, one-by-one.
A final, exemplary solution involves attaching a magnetic resonance device, or marker tag, to each sponge, which are then scanned by appropriate equipment (see U.S. Pat. Nos. 5,057,095 and 5,664,582). The problem with this solution is that both the marker tags and the scanning equipment are expensive and do not necessarily work well in an operating room environment. As acknowledged in the '582 patent, the scanner must be essentially parallel to the marker tag inside a wadded up sponge. If the marker tag is bent or folded, a signal from the tag may be difficult to identify. In addition, the scanning equipment may give false counts if the operating room contains objects, other than the marker, that also generate or respond to magnetic energy.
Many other problems and disadvantages of the prior art will become apparent to one skilled in the art after comparing such prior art with the present invention as described herein. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Technical Field
The present invention relates to an implant and to a method of securing an implant to a bone. More particularly, the present invention relates to an implant for securing to bone with bone cement, and to a method of securing an implant to a bone with bone cement.
2. Description of the Prior Art
Implants are often secured to bone with a material such as polymethylmethacrylate (PMMA), hereinafter referred to as "bone cement" or simply "cement". The cement bonds between a surface of the implant and a surface of the bone to secure the implant to the bone.
Often the bone cement is applied as a slab, for example between adjoining flat surfaces of a patellar implant and a patella. There may be defects in the cement such as an air bubble, an impurity or unreacted PMMA powder. It is known for slabs of bone cement to crack. With bone cement as with many materials a crack often initiates at the site of a defect. Or, a slab of bone cement could fail and crack from other causes such as stress or trauma. If bone cement is present in a continuous mass such as a slab, a crack propagates through the slab, resulting in complete failure of the cement system.
Another concern with bone cement is the maximum force (such as torque) which can be transferred, through the cement, between the implant and the bone. In the case of a slab, the maximum torque is related to the adhesive interfacial shear stress between the cement and the implant. | {
"pile_set_name": "USPTO Backgrounds"
} |
The invention relates to an internal combustion engine comprising an engine unit support elastically suspended in a crankcase and an oil pump driven by the crankshaft of the engine. | {
"pile_set_name": "USPTO Backgrounds"
} |
Through the Swedish patent SE 532 372, which corresponds to EP 2 145 057, a similar arrangement is previously known.
This previously known arrangement is to a springy attachment arrangement, adapted to be able to be firmly fastened to a first construction, such as a fixed or bearing construction, such as a frame work, and in such a firmly fastened position be able to hold a second construction, such as a side related and/or subordinated construction, such as a false ceiling built of cross bars and gypsum board, where the arrangement has a first partial portion interactable with the first construction and a second partial portion interactable with the second construction.
The embodiments shown in the document comprise torque transmission connection means between the two partial portions which to a certain degree are sensitive in the transmission between the two portions which may imply difficulties in the transmission of torque between the portions. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Field of the Invention
This invention relates to magnetic recording media and more particularly, to an improvement in magnetic recording layer media such as used for video tape recorders.
2. Description of the Prior Art
In recent years, there have been introduced onto the market video tape recorders of the long-time picture recording type. The recorders of this type are characterized by a magnetic head of narrow width which provide high recording density of the magnetic recording tape, thus imposing a great load on the magnetic tape.
Also, home video tape recorders have now come into wide use, and small-size, portable video tape recorders are increasing in number. The recording and reproducing system of these apparatus is a so-called helical capstan system using rotary magnetic heads by which a still picture can be reproduced. In the helical capstan system, when a pause mechanism is operated on recording or a still picture is reproduced, the magnetic head alone is allowed to rotate without feeding the magnetic tape, so that the magnetic tape is repeatedly scanned on the same portion. The portable video tape recorder of the just-mentioned type is often used under high temperature and high humidity conditions or at very low temperature in the open. Known magnetic recording tapes are rather unsatisfactory for use under these environmental or climatic conditions for still picture-reproducing or long-time reproducing purposes. Typical known magnetic recording tapes for the video tape recorder are obtained by applying onto a support such as polyester film or the like, magnetic paints which comprise magnetic powders, binders, carbon black and lubricants such as choresterin butyrate, silicone, graphite and molybdenum disulfide. When these tapes are subjected to long-time reproduction or still picture reproduction under high or low temperature conditions, there are encountered problems such as blooming and exudation of the lubricant used, head clogging, and abrasions produced on the tape coupled with rather poor magnetic characteristics. | {
"pile_set_name": "USPTO Backgrounds"
} |
Various information recording techniques have been developed following the increase in volume of information processing in recent years. Particularly, the areal recording density of HDDs using the magnetic recording technique has been increasing at an annual rate of about 100%. Recently, the information recording capacity exceeding 60 GB has been required per 2.5-inch magnetic disk adapted for use in a HDD or the like. In order to satisfy such a requirement, it is necessary to realize an information recording density exceeding 100 Gbits/inch2. In order to achieve the high recording density in a magnetic disk for use in a HDD or the like, it is necessary to reduce the size of magnetic crystal grains forming a magnetic recording layer serving to record information signals, and further, to reduce the thickness of the layer. However, in the case of conventionally commercialized magnetic disks of the in-plane magnetic recording type (also called the longitudinal magnetic recording type or the horizontal magnetic recording type), as a result of the advance in size reduction of magnetic crystal grains, there has been the occurrence of a thermal fluctuation phenomenon where the thermal stability of recorded signals is degraded due to superparamagnetism so that the recorded signals are lost. This has been an impeding factor for the increase in recording density of the magnetic disks.
In order to solve this impeding factor, magnetic recording media of the perpendicular magnetic recording type have been proposed in recent years. In the case of the perpendicular magnetic recording type, as is different from the case of the in-plane magnetic recording type, the easy magnetization axis of a magnetic recording layer is adjusted so as to be oriented in a direction perpendicular to the surface of a substrate. As compared with the in-plane recording type, the perpendicular magnetic recording type can suppress the thermal fluctuation phenomenon and thus is suitable for increasing the recording density. As such a perpendicular magnetic recording medium, there is known a so-called two-layer perpendicular magnetic recording disk comprising, over a substrate, a soft magnetic underlayer made of a soft magnetic substance and a perpendicular magnetic recording layer made of a hard magnetic substance, as is described in, for example, JP-A-2002-74648.
In the meantime, a conventional magnetic disk has a protective layer and a lubricating layer on a magnetic recording layer formed over a substrate, for the purpose of ensuring the durability and reliability of the magnetic disk. Particularly, the lubricating layer used at the outermost surface is required to have various properties such as long-term stability, chemical substance resistance, friction properties, and heat resistance.
In order to satisfy such a requirement, perfluoropolyether-based lubricants having hydroxyl groups in molecules have often been used conventionally as lubricants for magnetic disks. For example, according to JP-A-S62-66417 (Patent Document 1) or the like, there is known a magnetic recording medium or the like coated with a perfluoroalkylpolyether lubricant having a structure of HOCH2CF2O(C2F4O)p(CF2O)qCH2OH. It is known that when hydroxyl groups are present in molecules of a lubricant, the adhesion properties of the lubricant to a protective layer can be obtained by the interaction between the protective layer and the hydroxyl groups.
Patent Document 1: JP-A-S62-66417 | {
"pile_set_name": "USPTO Backgrounds"
} |
The present invention relates to a portable power working machine such as a chain saw, a power cutter, a hedge trimmer, etc., which is provided with an internal combustion engine as a driving power source for driving the working components thereof, and in particular, to a portable power working machine which is designed to prevent as much as possible an air cleaner attached to an air intake system of an internal combustion engine from being clogged with dust.
A conventional portable power working machine, such as a chain saw, is generally constructed such that a small air-cooled internal combustion engine acting as a driving power source for driving the working components, such as a saw chain, is mounted in a main housing, that a cooling fan driven by the internal combustion engine is disposed on one side of the main housing, and that a carburetor chamber housing therein an air cleaner and a carburetor is disposed on an upper rear side of the internal combustion engine.
In the operation of the portable power working machine as described above, dust that includes Sawdust of relatively large size, powder of cut material and sand-like dust is inevitably generated. When dust of those kinds is allowed to enter together with air into the air intake system of the internal combustion engine, and to collect on the filter element of the air cleaner, the clogging of the filter results, thus giving rise to an irregularity of the engine as well as a deterioration of performance of the engine due to an insufficiency in the flow rate of intake air. Accordingly, it is required in the operation of the portable power working machine to frequently clean the air cleaner, etc., which is a task that is quite troublesome for the operator.
The present invention has been made to solve the aforementioned problems. In particular, it is an object of the present invention to provide a portable power working machine which is capable of preventing as much as possible an air cleaner of the air intake system of a small air-cooled internal combustion engine acting as a driving power source for working components from being clogged with dust, thereby relieving an operator from the task of frequently cleaning the air cleaner.
With a view to attaining the aforementioned object, there is provided, in accordance with the present invention, a portable power working machine comprising a small air-cooled internal combustion engine received in a main housing, a cooling fan which is adapted to be driven by the internal combustion engine and disposed on one side of the main housing, and an air cleaner disposed in the air-intake system of the internal combustion engine; wherein the power working machine is featured in that part of air introduced into the main housing by means of the cooling fan is allowed to be sucked again by the cooling fan so as to be recirculated.
In a preferred embodiment, a carburetor chamber housing therein the air cleaner and a carburetor is placed in the air-intake system of the internal combustion engine, wherein part of air introduced into the main housing by means of the cooling fan is allowed to be sucked again by the cooling fan, thereby enabling it to be recirculated through the carburetor chamber and a circulating air duct disposed outside the carburetor chamber, and at the same time, part of air introduced into the carburetor chamber is allowed to be introduced from the air cleaner into the internal combustion engine.
In this case, preferably, the circulating air duct may be disposed in such a manner that the open end on the upstream side thereof is positioned lower than the air cleaner housed in the carburetor chamber, while the open end on the downstream side thereof may be positioned in the vicinity of the air-intake port of the cooling fan.
In a more preferred embodiment, the circulating air duct may be constructed such that the upstream region of the passageway has a larger cross-sectional area than that of the downstream region of the passageway, and that a flange-like guiding member is placed in the vicinity of the aforementioned downstream side open end of the circulating air duct, thereby effectively enhancing the air intake power of the cooling fan.
A typical example of a portable power working machine in which the present invention is especially advantageous is a chain saw, which includes a saw chain set composed of a saw chain and a guide bar that is located on the side of the main housing opposite from the cooling fan and the carburetor chamber housing. Because chain saws produce large quantities of dust, including relatively large particles, reducing the rate of accumulation of dust on the air cleaner offers important improvements in the chain saw.
According to the aforementioned preferred embodiment of the portable power working machine, when the power working machine is operated, the air (cooling air) that has been introduced from one side of the main housing by the suction of the cooling fan and hence accelerated and pressurized is transmitted so as to cool the internal combustion engine and then discharged through a discharge port formed in the main housing toward the external atmosphere, part of air thus introduced into the main housing being sucked again by the cooling fan after passing through the carburetor and the circulating air duct so as to be recirculated, whereas part of the air introduced into the carburetor chamber is sucked into the internal combustion engine through the air cleaner and carburetor during the intake stroke of the engine.
In this case, since the circulating air duct is disposed in such a manner that the open end on the upstream side thereof is positioned lower than the air cleaner housed in the carburetor chamber, and the open end on the downstream side thereof is positioned in the vicinity of the air-intake port of the cooling fan, most of the dust existing in the air that has been introduced into the carburetor chamber is caused, due to the gravity thereof, to be sucked by the Cooling fan after passing through the carburetor chamber and the circulating air duct, thus preventing most of the dust from reaching the air cleaner.
As a result, it is now possible to minimize the clogging of the air cleaner, thus making frequent cleaning of the air cleaner unnecessary and improving the efficiency of work.
In another preferred embodiment of the portable power working machine according to the present invention, the air cleaner and carburetor are placed in the air-intake system of the internal combustion engine, wherein part of external air that has been pressurized and accelerated due to the sucking power of the cooling fan is caused to be sucked again by the cooling fan after passing through a discharge port formed at the outer periphery of a volute case and through the circulating air duct, thereby enabling part of external air to be recirculated, and at the same time, part of air flowing through the circulating air duct is caused to be separated from an intermediate portion of the circulating air duct and allowed to flow in a direction which is approximately orthogonal to the direction of the intermediate portion of the circulating air duct, thereby enabling the air to be introduced into the internal combustion engine through the air cleaner and the carburetor.
In this case, preferably, the circulating air duct is constituted by an upstream side passageway extending from the discharge port toward the air cleaner, the aforementioned intermediate passageway being disposed below the filter element of the air cleaner and communicating with the upstream side passageway, and a downstream side passageway communicating with the intermediate passageway and having an open distal end which is positioned in the vicinity of the intake port of the cooling fan.
In another preferred embodiment, a carburetor chamber housing a carburetor is placed in the air-intake system of the internal combustion engine, and the aforementioned air cleaner having a sheet-like filter element as a partitioning wall is disposed in the carburetor chamber.
According to the aforementioned preferred embodiment of the portable power working machine, when the power working machine is operated, the air (cooling air) that has been-introduced from one side of the main housing by the suction of the cooling fan and hence accelerated and pressurized is transmitted so as to cool the internal combustion engine and then, discharged through a discharge port formed in the main housing toward the external atmosphere. Part of air thus introduced into the main housing is sucked again by the cooling fan after passing through a discharge port formed at the outer periphery of a volute case and through the circulating air duct, thereby enabling part of the air to be recirculated. At the same time, part of air flowing through the circulating air duct is caused to be separated from an intermediate portion of the circulating air duct and allowed to flow in a direction which is approximately orthogonal to the direction of the intermediate portion of the circulating air duct, thereby enabling the air to be introduced into the internal combustion engine through the air cleaner and the carburetor.
In this case, since most of the dust present in the air being introduced from the discharge port into the circulating air duct is caused, due to the gravity and inertia thereof, to be sucked by the cooling fan after passing through the circulating air duct. The air which is separated from an intermediate portion (an intermediate passageway) disposed lower than the air cleaner in the circulating air duct and directed to flow in a direction orthogonal to the intermediate passageway can be substantially prevented from being contaminated by the dust.
As a result, it is now possible to minimize the clogging of the air cleaner, thus making frequent cleaning of the air cleaner unnecessary and improving the efficiency of work.
Further, although the quantity of air introduced into the internal combustion engine may be sharply reduced at the moment when the throttle valve of the carburetor is turned from a relatively wide-opened state back to a minimum opening (opening at idling of the engine), since the cooling fan can keep rotating at a high speed for a while due to the inertia, the sucking action by the cooling fan to the dust in the air cleaner chamber can be maintained, thereby making it possible to minimize the clogging of the air cleaner by this action of the cooling fan.
For a better understanding of the present invention and further advantages thereof, reference may be made to the following description of an exemplary embodiment, taken in conjunction with the accompanying drawings. | {
"pile_set_name": "USPTO Backgrounds"
} |
A large majority of fisherman who use minnows or other type of live bait, purchase the minnows from bait shops and marinas. Bait vendors frequently maintain minnows alive in large quantities in refrigerated and aerated tanks and dispense small measured quantities which necessitates the use of small nets to remove the proper quantity of minnows from the tanks to count and place them into the customer's minnow bucket. This procedure not only requires an attendant, but frequently results in annoying delays to the customer while waiting for the attendant to arrive and then collect and dispense the minnows. Also, some of the minnows are injured by the handling and soon die.
Various dispensing machines have been proposed, some coin operated, for assisting the attendant to more easily catch and count the minnows. Machines have been proposed to dispense a predetermined number of the minnows without the assistance of an attendant. However, most machines have been complex and involve a large amount of machinery to function.
Thus, a need exists for an apparatus that is simple, fast and efficient and whereby the operator may serve him or herself without assistance from an attendant whose attention is required only when the apparatus is empty. | {
"pile_set_name": "USPTO Backgrounds"
} |
The flight direction of the ball is the result of the player's swing of the club at impact with the ball. To achieve the straighter flight with the greatest force of impact is the pursuit of all golfers. It is generally accepted that a player should not shift his body away from the target during his backswing; he should remain on balance during his backswing. It is also generally accepted that a player should shift his body toward the target during the start of his downswing. The player doing these two things has the best chance of the ball having a straight flight and long distance for the club used and the force of the swing.
Players do not generally achieve these two things because they can't perceive when they improperly shift their body away from the target on their backswing and they can't perceive that they do not properly shift their body toward the target at their downswing.
Various devices have been developed to help the player achieve a better swing, but most, if not all, have fallen into disuse because they do not give the player an immediate direct "feel" and signal indication of whether he has properly and/or improperly controlled his body relative to the increments of his swing. The "feel" is the more important. The "feel" of making a proper swing is almost impossible to perceive and recognise. It is believed that none of the prior art apparatus give the player not only the "feel" of making a proper swing but also fail to give him the "feel" of making an improper swing. Until a player gets this "feel" he cannot controllably and predictably execute a proper swing. | {
"pile_set_name": "USPTO Backgrounds"
} |
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