A thrust reverser is disclosed for a turbofan type turbojet engine assembly with a cowling having an inner cowling surface forming an outer boundary of a gas flow duct, and an outer cowling surface spaced from the inner cowling surface, the inner and outer cowling surfaces joining at a rearmost edge of the cowling, the thrust reverser having a thrust reverser baffle with an outer baffle surface and an inner baffle surface, a forward linkrod pivotally connected to a forward portion of a thrust reverser baffle and to the cowling, and a rear linkrod pivotally connected to the thrust reverser baffle and to the cowling. The thrust reverser baffle is movable between a forward thrust position wherein the outer baffle surface is substantially flush with the outer cowling surface, a forward portion of the thrust reverser baffle covering an inner rear cowling portion having the inner cowling surface, and a reverse thrust position in which the reverse thrust baffle is disposed rearwardly of the rearmost cowling edge so as to redirect gases flowing through the gas flow duct. When in the forward thrust position, the forward and rear linkrods are totally enclosed between the spaced apart inner and outer cowling surfaces.

The present invention relates to a thrust reverser for a turbojet engine having a thrust reverser baffle movable to the rear of an engine cowling assembly to redirect gases emanating from the cowling into a reverse thrust direction.
Turbofan-type turbojet engines are well known in the art and typically comprise a fan at the front of the turbojet engine which directs a flow of bypass air through a duct bounded by the engine cowling on the inside and a fan cowling on the outside. The generally annular duct bounded by the engine cowling and the fan cowling may channel both the bypass flow and the primary exhaust gas flow at a downstream portion from the turbojet engine, or may channel only the bypass flow.
In aircraft on which the turbojet engine is mounted outside of the airframe structure, the fan cowling and the engine cowling are configured to form boundaries of the bypass flow duct and to provide aerodynamic outer surfaces to reduce drag.
FIGS. 1 and 2 illustrate a known pivoting door-type thrust reverser associated with the cowling of a turbofan-type turbojet engine. As illustrated in FIG. 1, the upstream portion of the cowling which defines the outer limits of the bypass flow duct and which is generally concentrically arranged about the turbojet engine (not shown) is designated as 1 and generally comprises an external cowling panel and an internal cowling panel interconnected by a frame 6. The outer surface of the external cowling panel has an aerodynamic surface over which the air external to the engine passes during aircraft flight. The inner surface of the inner cowling panel defines the outer boundary of the bypass flow duct through which the bypass flow passes in the direction of the arrow.
The cowling also comprises a thrust reverser 2 and a downstream cowling portion 3. The thrust reverser 2 comprises a door 7 pivotally attached to the cowling so as to pivot about a transverse axis such that it is movable between a closed, forward thrust position, illustrated in FIG. 1, and an open, reverse thrust position, in which the forward end (towards the left as viewed in FIG. 1) of the thrust reverser door 7 is moved outwardly from the cowling, while a rear portion is moved inwardly into the bypass flow duct so as to redirect at least a portion of the bypass flow through an opening in the cowling in a direction that has a reverse thrust component.
A known actuator 8 for moving the door 7 between its forward thrust and reverse thrust positions may comprise a hydraulic cylinder extending through and mounted to the frame 6, and having an extendible and retractable piston rod connected to the thrust reverser door 7.
The thrust reverser door 7 has an outer panel 9, an inner door panel 11 and the forward end of the door 7 may have a deflector to maximize the efficiency of the thrust reverser when the door 7 is in the reverse thrust position. The inner surface 11 tapers toward the outer surface of the door 7 at the forward end of the door, forming a cavity when in the forward thrust position.
A plurality of thrust reverser doors 7 may be incorporated into the cowling, such doors being circumferentially spaced around the periphery of the cowling as illustrated in FIG. 2. A portion 18 of the cowling extends axially between a forward part 4 and a rear part of the cowling adjacent thrust reverser doors 7 to provide structural rigidity to the cowling and to provide pivot mounting points for attaching the doors 7 to the cowling. French Patents 2,618,853; 2,618,852; 2,621,082; 2,627,807; 2,634,251; 2,638,207; and 2,651,021 illustrate typical, known thrust reversers.
In some applications, installation of a known type of thrust reverser raises substantial difficulties and may, for all practical purposes, be impossible. These difficulties arise in turbofan engines having a very high bypass ratio and which incorporate a fan cowling having a short axial length compared to the axial length of the jet engine cowling. In these instances the use of such an axially short fan cowling produces a relatively short bypass flow duct and renders the use of such known type of thrust reversers virtually impossible.
French Patent 2,722,534 discloses a thrust reverser for a turbofan type turbojet engine attached to the cowling assemblies by linkrods. This known design entails the drawback of positioning a downstream or rear linkrod in the acceleration zone of the gas flow inside the bypass flow duct and, in particular, in a zone where the linkrod pivots on the jet engine cowl. Since the speed of the gas flow is close to, or exceeds the speed of sound during aircraft cruising flight, the location of this linkrod causes substantial aerodynamic disturbances. Moreover, further aerodynamic losses are caused by notching or embossing the thrust reverser baffle or the associated fixed cowling structure to allow the displacement of the rear linkrod during movement of the baffle between the forward and reverse thrust positions. Another drawback is caused by stops which must be mounted on the engine cowling structure to retain the rearmost edge of the thrust reverser baffle on the engine cowling when the baffle is in the reverse thrust position. Consequently, when the baffle is moved to the forward thrust position, these stops project beyond the engine cowling surface causing further aerodynamic disturbances.

Turbojet engine thrust reverser having movable rear baffle pivattally connected by forward and rear linkrods which are totally enclosed in the forward thrust mode


The method and apparatus of the invention effects compression of an analog electrical signal (e.g., representing an interferogram) by introducing into it a component that is a cubic function thereof, normally as a nonlinear negative signal in a feedback loop of an Op Amp. The compressed signal will most desirably be digitized and then digitally decompressed so as to produce a signal that emulates the original.

Generated analog electrical signals are of course commonly converted and utilized in digital form. In a variety of such schemes the signal-to-noise ratio (S/N) of the signal-generating device is much better than is the dynamic range of the associated analog-to-digital (A/D) convertor. This is true, for example, in Fourier transform infrared (FT-IR) spectrometers, in which a mercury cadmium telluride (MCT) photoconductive detector is typically used for detecting radiation in the mid-infrared region of the spectrum. Most such FT-IR instruments have 16-bit A/D convertors for digitizing the amplified MCT signal; because of the relatively high S/N of the detector, however, digitization of its signals by a 20-bit convertor is feasible.
An FT-IR spectrometer will typically generate an A.C. signal that, for the most part, oscillates about zero but that has a small region (the "center burst") near the zero path difference (ZPD) at which the signal peaks to 100 to 1000 times that level. Consequently, it is conventional to enhance the dynamic range of the FT-IR signal by gain ranging; that is, to set the amplification gain to some known, relatively high level during data acquisition, and to decrease it to some other known level in the region of the ZPD so as to avoid overloading of the A/D convertor. The technique is however disadvantageous for a number of reasons. Not only must the two gain levels be known very accurately, but there is also a tendency for switching noise generation because the data-acquisition rate can often exceed tens of kilohertz, thus subjecting the switch to fast settling time demands; it is very difficult, moreover, to remove the slight offsets from zero that can occur during the amplification changes.
The prior art teaches various means for effecting signal compression. Nonlinear devices, such diodes, transistors and FET's, have for example been incorporated into the feedback loops of Op Amps, as in U.S. Pat. No. 4,899,115, issued to Christian on Feb. 6, 1990, and U.S. Pat. No. 4,627,094, issued to Scholz on Dec. 2, 1986. U.S. Pat. No. 4,349,787, issued to Laupman on Sep. 14, 1982, and U.S. Pat. No. 4,400,583, issued to Bloy on Aug. 23, 1983, provide apparatus in which devices incorporated into amplifier feedback loops serve as adjustable gain controls, which are in turn controlled by other, secondary sensing circuitry.
These prior art compression algorithms also suffer however from certain deficiencies and drawbacks, rendering them unsuitable or unusable for many applications, including that to which the instant invention is (in its preferred embodiments) directed. This is attributable primarily to the fact that the compression functions of the devices involved are either insufficiently known, are susceptible to temperature changes, or are time averaged, thus making computation of the digitized signal, and emulation of the original uncompressed signal, inconsistent and difficult, if indeed possible at all.
Accordingly, it is the broad object of the present invention to provide a novel method, apparatus and system for enhancing analog electrical signal properties, by compression.
More specific objects are to provide such a method, apparatus and system by which the signal-to-noise ratio of the signal can be maximized so as to make use of the entire dynamic range of a digitizer, and to provide a method and system for digitally decompressing the signal so as to faithfully emulate the original, uncompressed signal.
Additional objects of the invention are to provide such a method, apparatus and system in which compression is effected in a manner that is highly efficient and effective, and by means that is relatively incomplex, highly reliable, stable, convenient to calibrate and utilize, and relatively inexpensive and facile to produce.

Method and apparatus for signal compression


A gas dynamic pressure bearing includes a shaft centered on a central axis extending in an up-down direction, and a sleeve that faces at least a portion of the shaft in a radial direction. The portion in which the sleeve and the shaft face each other in the radial direction includes a first dynamic pressure portion at each of both ends in the axial direction, and a second dynamic pressure portion between the first dynamic pressure portions. In the first dynamic pressure portion, one of the sleeve and the shaft includes dynamic pressure grooves arranged in a circumferential direction. A sum of center angles of groove widths of the dynamic pressure grooves in a cross-section cut along a plane orthogonal to the central axis is about 144° or more and about 216° or less.

A conventional gas dynamic pressure bearing includes a ring having a cylindrical outer peripheral surface region, and a housing having a tubular portion having an inner peripheral surface region facing the outer peripheral surface region. The outer peripheral surface region or the inner peripheral surface region is provided with a plurality of radial dynamic pressure grooves that act as a radial dynamic pressure bearing region between these two surface regions.
The gas dynamic pressure bearing has a configuration in which air is compressed to form a radial dynamic pressure bearing region. Since it is non-contact, it can cope with high rotation and has high noise reduction.
The conventional gas dynamic pressure bearing has a configuration in which air is compressed by a radial dynamic pressure groove. However, when the compression efficiency of the air in the radial dynamic pressure bearing region is low, the rotation of the ring may become unstable.

Gas dynamic pressure bearing, motor, and blower


Optical characterization of lateral features of a pattern is provided. A plane-wave optical response is calculated for each feature. At least one of these plane-wave responses is calculated from an effective optical property (e.g., a waveguide modal refractive index). Such effective optical properties depend on feature geometry and on intrinsic material optical properties. The plane-wave responses for each feature are combined to generate a modeled pattern response. By fitting the modeled pattern response to a corresponding measured pattern response, estimates for pattern feature parameters are obtained. The use of an effective optical property improves model accuracy, especially for features having a size on the order of a wavelength or less, without significantly increasing computation time.

Manufacturing processes for producing products usually rely on quantitative measurements to provide information required for process control. Such measurements can be made on the final product, and/or on intermediate stages of the product within the manufacturing process, and/or on tools/fixtures used in the manufacturing process. For example, in semiconductor chip fabrication, measurements can be performed on finished chips (i.e., final product), on a wafer patterned with a photoresist (i.e., intermediate stage), or on a mask (i.e., a tool or fixture). Frequently, as in the case of semiconductor chip fabrication, these measurements are performed on structures having small dimensions. Furthermore, it is highly desirable to perform process control measurements quickly and non-destructively, in order to ensure a minimal impact on the process being controlled. Since optical measurements can be performed quickly, tend to be non-destructive, and can be sensitive to small features, various optical process control measurements have been developed.
Optical process control measurements can often be regarded as methods for measuring parameters of a pattern. For example, a pattern can be a periodic one-dimensional grating of lines on the surface of a wafer, and the parameters to measure can be line width, line spacing and depth of the grating. To measure these parameters, an optical response of the pattern is measured. For example, reflectance as a function of wavelength can be measured. Typically, the optical response will depend on the parameter (or parameters) of interest in a complicated way such that direct parameter extraction from measured data is impractical. Instead, a mathematical model is typically constructed for the pattern, having the parameters of interest as variables. Within the model, a modeled optical response is calculated corresponding to the measured optical response. The parameters of interest are then determined by adjusting the variables to fit the modeled response to the measured response. Various optical process control measurements differ depending on the measured response(s), and on the kind of mathematical model employed.
In particular, the mathematical model employed for such measurements can be more or less rigorous. Generally, more rigorous models provide improved fidelity between measured and modeled results, but require greater calculation time and/or processing resources. In addition, rigorous models can require more detailed measurements, which tends to increase measurement time and/or cost. Less rigorous models reduce calculation time and/or required processing resources, but tend to provide reduced fidelity between measured and modeled results.
A rigorous modeling approach described by Moharam et al. in Journal of the Optical Society of America (JOSA), A12, n5, p 1068–1076, 1995 is known as the rigorous coupled wave analysis (RCWA). The RCWA is limited to periodic structures such as a grating, and the required computation time is generally large, especially for a grating having a period substantially larger than a wavelength. Rigorous modeling approaches other than the RCWA have also been developed, but such approaches have similar advantages and drawbacks as the RCWA. The RCWA was first introduced by K. Knop in JOSA, v68, p 1206, 1978, and was later greatly improved by Moharam et al. in the above-referenced article. Some implementations of the RCWA are described in U.S. Pat. Nos. 6,590,656 and 6,483,580 assigned to KLA-Tencor, U.S. Pat. No. 5,963,329 assigned to IBM, and U.S. Pat. No. 5,867,276 assigned to Bio-Rad.
An example of a less-rigorous modeling approach is referred to herein as the scalar model. The basic idea of the scalar model is to divide the pattern of interest into several features, calculate an optical response (e.g., complex amplitude reflection or transmission coefficient) of each feature in a plane-wave approximation (i.e., as if each feature had infinite lateral extent), and then combine the calculated plane-wave responses of each feature to obtain an approximate modeled response for the pattern. For example, if features 1 and 2 have plane-wave complex amplitude reflection coefficients r1 and r2 respectively, where r1 and r2 are referred to the same reference plane, then the combined reflectance R in the scalar model is given by R=|a1r1+a2r2|2, assuming lateral coherence. Here a1 and a2 are the areal fractions of features 1 and 2 respectively (i.e., the fraction of the total pattern area in features 1 and 2 respectively). Thus diffraction is ignored in the scalar model, but interference between features can be accounted for.
The scalar model was originally proposed by Heimann et al. (Journal of the Electrochemical Society, v131, p 881, 1984; ibid, v132, p 2003, 1985). Applications of the scalar model are considered by Cho et al. (Journal of Vacuum Science and Technology (JVST), B20, p 197, 2002), Maynard et al. (JVST, B13, p 848, 1995; JVST, B15, p 109, 1997), and Lee et al. (International Conference on Characterization and Metrology for ULSI Technology, Gaithersburg, Md., Mar. 23–27 1998, AIP conf. proc., v449, p 331, 1998). Aspects of the scalar model are considered in U.S. Pat. Nos. 6,281,974 and 6,100,985 by Scheiner et al., assigned to Nova Measuring Instruments Ltd.; U.S. Pat. Nos. 6,623,991 and 6,340,602 by Johnson et al. assigned to Therma-Wave Inc. and Sensys Instruments respectively; and U.S. patent application Ser. No. 10/607,410 by Li et al. entitled "Method and Apparatus for Examining Features on Semi-Transparent Substrates" and assigned to n&k Technology Inc.
This conventional scalar model works well for large features (i.e., features substantially larger than an optical wavelength), but its accuracy decreases with feature size, and it typically does not provide sufficiently accurate results for features having a size on the order of a wavelength or smaller. However, the scalar model is much simpler than rigorous modeling approaches, such as the RCWA, and thus requires far less computation time and/or processor resources. Accordingly, it would be an advance in the art to improve the accuracy of the scalar model for features having small size.
Thus an object of the present invention is to provide a model having improved accuracy compared to the scalar model for patterns having small feature sizes. A further object of the invention is to provide a model having reduced computation time compared to rigorous modeling approaches, such as the RCWA. Yet another object of the invention is to achieve the preceding two objects simultaneously.

Optical determination of pattern feature parameters using a scalar model having effective optical properties


The invention is related to thermal imageable dielectric layers and thermal transfer donors and receivers comprising dielectric layers. The thermal transfer donors are useful in making electronic devices by thermal transfer of dielectric layers having excellent resistivity, good transfer properties and good adhesion to a variety of receivers.

Thermal transfer processes are well known in applications such as color proofing as a means of dry transferring or printing of dye and/or pigment layers. Such thermal transfer processes typically use a laser to induce the image-wise thermal transfer of material.
Laser-induced thermal transfer processes typically use a donor element, including a layer of material to be transferred, referred to herein as a transfer layer, and a receiver element, including a surface for receiving the transferred material. Either the substrate of the donor element or the receiver element is transparent, or both are transparent. The donor element and receiver element are brought into close proximity or into contact with each other and selectively exposed to laser radiation, usually by an infrared laser. Heat is generated in the exposed portions of the transfer layer, causing the transfer of those portions of the transfer layer onto the surface of the receiver element. If the material of the transfer layer does not absorb the incoming laser radiation, the donor element should include a heating layer, also known as a light-to-heat conversion (LTHC) layer or a transfer-assist layer, in addition to the transfer layer.
In a typical laser-induced digital thermal transfer process the exposure takes place only in a small, selected region of the assembly at a time, so that transfer of material from the donor element to the receiver element can be built up one region at a time. The region may be a pixel, some portion of a pixel or a plurality of pixels. Computer control facilitates the transfer at high speed and high resolution. Alternatively, in an analog process, the entire assembly is irradiated and a mask is used to selectively expose desired portions of the thermally imageable layer.
A particular need for printable electronics includes thermally imageable insulating layers or dielectric passivation layers. WO 2005/004205, for instance, discloses a method of forming a pattern of filled dielectric material on a substrate by a thermal transfer process comprising exposing to heat a thermally imageable donor element comprising a base film, a light to heat conversion (LTHC) layer, and a transfer layer of dielectric material. In a thin film transistor (TFT), the dielectric layer serves to insulate the gate layer from the semiconductor and source-drain layers. Its primary function is to allow the passage of fields, but not currents. A fundamental requirement is that the dielectric layer possess high volume resistivity, greater than 1014 ohm-cm, to prevent leakage currents; and be largely pinhole free to prevent catastrophic shorts between conductive layers. The dielectric layer also must have high purity in order not to dope the adjacent semiconductor layer; it should be thin, for instance, about 5 microns or less, and have a high dielectric constant for low-voltage operation.
Additional requirements for successful thermal transfer of the dielectric layer include: the dielectric composition must be coatable and therefore must have adequate solubility and/or dispersability in a suitable solvent; it must exhibit good interfacial behavior (mechanical, electrical) with adjacent layers, including the receiver, the conducting layers (gate and source-drain layers) and the semiconductor layer; and it must be printable by thermal transfer and maintain its insulating properties. In order for an insulating layer to meet this last requirement and be printed in one printing cycle, it needs to exhibit good adhesion to all previous layers including receiver, conducting layers and semiconductor layers. It must print under approximately the same conditions (e.g., same drum speed and power) onto all of the different previous layers, and it must print with acceptable quality. For example, defects caused by the thermal transfer process including: pinholes, bubbles, cohesive failure, breaks at swath boundaries, and co-transfer of materials from the adjacent donor substrate layers (typically the LTHC layer); must be very minimal in order not to degrade electrical performance to an unacceptable level.
There is a need for thermal transfer donors that allow patterned thermal transfer of dielectric layers with excellent resistivity that exhibit good transfer properties and good adhesion to a variety of materials. Particularly desirable are thermal transfer donors wherein, after transfer, the patterned layer has the uniformity, continuity and resistive properties required of a dielectric layer in electrical applications, for instance in applications for capacitors or thin film transistors.

Thermally imageable dielectric layers, thermal transfer donors and receivers


A latch assembly of a seat is provided in a vehicle. The latch assembly includes a base including a first pin and a second pin. A first latch includes a first housing and a first latch mechanism at least partially enclosed within the first housing. The first latch is pivotally coupled to the base. A second latch includes a second housing and a second latch mechanism at least partially enclosed within the second housing. The second latch is pivotally coupled to the base. The first latch is disposed in its latched position when the first latch engages the first pin, and the second latch is disposed in its latched position when the second latch engages the second pin. The first latch and the second latch are not disposed in their respective latched positions at the same time.

Automobile manufacturers do not currently mass-produce passenger motor vehicles specifically designed to transport passengers having physical limitations, either as a driver or as a non-driving passenger. Consequently, mass-produced passenger vehicles are modified, or retrofitted, by a number of aftermarket companies dedicated to supplying vehicles to physically limited passengers. Such vehicles can be modified by removing certain parts or structures within a vehicle and replacing those parts with parts specifically designed to accommodate the physically limited passenger. For example, in one configuration, a van is retrofitted with a ramp to enable a physically limited individual using a wheelchair to enter and exit the vehicle without the assistance of another individual.
Other known products for retrofitting a vehicle, such as a van, include wheel chair lifts, lift platforms, and lowered floor surfaces. In some instances, a floor of an original equipment manufacturer (OEM) vehicle is lowered or otherwise modified to accommodate an entry and exit of the physically limited individual through a side door or entrance of the vehicle. Once inside the vehicle, individual who uses the assisted entrance is located in a rear passenger compartment of the vehicle adjacent to or behind the side entrance.
In one known retrofitted vehicle, a floor of the OEM vehicle is lowered to accommodate the physically limited passenger, e.g., one seated in a wheelchair. In some vehicles, which are considered as viable candidates for retrofitting, the construction of the OEM vehicle requires significant modification to accommodate the lowered floor. Not only must a subfloor be added, but additional floor space inside the vehicle, and in particular, the rear passenger compartment. Even with a lowered floor, however, passenger seats located in the vehicle can still present an obstacle for a wheelchair to fit comfortably within the vehicle.

Seat base assembly and latching assembly for a rear-entry vehicle


A process for reclaiming ammonia from waste streams comprises reacting at least one waste stream with an excess of hydroxide to produce ammonia and water. The ammonia is removed from the reaction vessel and purified.

1. Field of Invention
This invention is directed to the recovery of ammonia from waste streams. More specifically, this invention is directed to systems and methods for processing used chemical bath solutions to reclaim ammonia.
2. Description of Related Art
Semiconductor wafers, such as silicon wafers, are used for fabricating integrated circuits and solar cells, among other uses. Semiconductor wafer production is a multi-part process. First, in general, a semiconductor ingot is grown, often by the Czochralski method of pulling crystal, and shaped. The ingot is then sliced into wafers and prepared, through multiple steps, for polishing, in a process often referred to as the chemical wafer process. The wafer is then polished and inspected in the polished wafer process. Depending on end-use, the polished wafers are optionally subjected to a process by which an epitaxial layer is deposited on the wafer in the epitaxy process.
The use of highly purified ammonia in semiconductor wafer processing is well known. For example, U.S. Pat. No. 5,846,386 to Hoffman et al., U.S. Pat. No. 5,496,778 to Hoffman et al. and U.S. Pat. No. 5,242,468 to Clark et al. disclose the use of highly pure ammonia and liquid cleaners in the manufacture of semiconductor wafers and other electronic components.
During silicon wafer manufacturing, wafers are typically cleaned using solutions containing ammonia. Two common such solutions are SC-1 and SC-2 (Standard Clean) chemical bath solutions. SC-1 chemical bath solutions are highly basic and contain an oxidizing agent, usually hydrogen peroxide, H2O2, which must be treated prior to disposal. Specifically, SC-1 chemical baths contain high purity ammonium hydroxide (NH4OH), hydrogen peroxide (H2O2) and water (H2O). After several cleaning cycles, SC-1 chemical bath solutions will also include silicon, in the form of H2SiO3. However, SC-1 cleaning has its disadvantages. SC-1 solution is costly. In addition, including SC-1 cleaning in the process of manufacturing semiconductor chips requires the addition of steps for chemical and waste water treatment. Thus, SC-1 cleaning increases the complexity and the cost of semiconductor chip manufacture.
In conventional silicon wafer manufacturing processes, chemical bath solutions are treated before being discarded. Using SC-1 as an example, SC-1 chemical bath solutions are mixed with SC-2 chemical bath solutions, which are dilute solutions of hydrochloric acid (HCl) and hydrogen peroxide (H2O2). The combined solution is then neutralized with sulfuric acid (H2SO4) to produce ammonium sulfate ((NH4)2SO4) and water. Ammonium sulfate and water may be discharged safely into sewer systems, but environmental concerns remain and further processing may be necessary to avoid adverse environmental impacts in the future.
In addition, SC-1 chemical bath solutions are the source of significant expense in silicon wafer manufacturing processes. Very high-purity ammonium hydroxide for the SC-1 chemical baths and the sulfuric acid, used to neutralize the SC-1/SC-2 chemical bath combined solution, are expensive. Sewer fees are also costly.
Some reprocessing methods exist in the art for purifying certain liquids on an industrial scale. For example, U.S. Pat. No. 4,828,660 discloses a method for the reprocessing of ultrapure liquids, specifically sulfuric and peroxydisulfuric acids. The repurification disclosed is performed by withdrawing acid/oxidant solution from the processing stream, subjecting the acid/oxidant solution to, purification processes and reintroducing the purified solution into the process stream. However, there is no reprocessing or repurification method available, for recovering ammonia from ammonium-rich waste streams.
Thus, there is a need for semiconductor wafer processing systems and processes that eliminate the expense and waste problems associated with SC-1 cleaning.


A reprogramming apparatus for vehicle, a reprogramming method and a vehicle including the same are provided. The reprogramming apparatus for the vehicle may include: a diagnostic unit configured to diagnose a plurality of controllers of the vehicle; a reprogramming unit configured to reprogram the plurality of controllers; and a gateway configured to control communication connection among the diagnostic unit, the reprogramming unit, and the plurality of controllers, wherein the gateway is configured to change a Controller Area Network (CAN) communication mode to a Controller Area Network with Flexible Data-rate (CAN-FD) communication mode when a communication mode change request is received from the reprogramming unit, check whether CAN-FD communication mode cancellation conditions are satisfied when the CAN communication mode has been changed to the CAN-FD communication mode, and change the CAN-FD communication mode to the CAN communication mode when the CAN-FD communication mode cancellation conditions are satisfied.

The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.
In general, vehicle controller area network (CAN) communication loads increase as vetronics are accelerated. To solve such issues, CAN with flexible data-rate (CAN-FD) communication has emerged.
CAN-FD communication has a higher data rate than CAN communication and can use a payload of up to 64 bytes.
Reprogramming for updating a controller of a vehicle can make the best use of such advantages of CAN-FD communication.
CAN-FD reprogramming can improve development efficiency and reduce maintenance time by rapidly performing controller update.
However, on-board diagnostics (OBD) regulations provide that a user must not use a CAN-FD function while a CAN network is operated because CAN-FD tolerance cannot be guaranteed.
Accordingly, diagnostic CAN communication is configured to support high-speed (HS) CAN communication because all controllers of a vehicle do not support CAN-FD communication.
For this reason, to satisfy requirements of OBD regulations, a CAN-FD programming module cannot be connected to diagnostic CAN communication to be used.
Since the CAN-FD reprogramming module cannot perform CAN-FD reprogramming through an OBD CAN channel as described above, a reprogramming speed for vehicle controller update decreases and maintenance time increases.
Accordingly, it may be necessary to develop a reprogramming apparatus for a vehicle which can perform CAN-FD reprogramming through an OBD CAN channel while satisfying OBD regulations.

Reprogramming apparatus for vehicle, reprogramming method thereof, and vehicle including the same


A retransmission apparatus is provided that uses a packet method for a DMB service and includes: a DMB receiver for receiving DMB data from a medium; a DMB transmission mode release unit that outputs an MPEG-2 TS by releasing a DMB transmission mode in the DMB data received from the DMB receiver; a channel information extractor that extracts channel information contained in a Fast Information Channel (FIC) of the DMB data in the DMB transmission mode release process of the DMB transmission mode release unit; a data information extractor that receives the MPEG-2 TS from the DMB transmission mode release unit and extracts data information indicating a location of an elementary stream from the received MPEG-2 TS; a channel information database (DB) that stores the channel information extracted by the channel information extractor and the data information extracted by the data information extractor as channel data; a first IP streamer that IP-streams the MPEG-2 TS output from the data information extractor; and a second IP streamer that IP-streams the channel data stored in the channel information DB.

1. Field of the Invention
The present invention relates to performing a quick channel change when a Digital Multimedia Broadcasting (DMB) signal using a high compression technique, such as H.264, is retransmitted to an Internet Protocol (IP)-based wired/wireless network.
2. Description of the Related Art
Digital Multimedia Broadcasting (DMB) is a Korean system standard for a multimedia broadcasting service comprising video based on Digital Audio Broadcasting (DAB: Eureka-147). DAB is a European digital radio broadcasting standard for simultaneously providing a compact disk (CD)-level high quality audio service and a data service.
In order to receive the DMB broadcasting service, a separate DMB receiver is required, and a DMB signal cannot be received through an Internet Protocol (IP)-based wired/wireless network in which a DMB receiver does not exist.
As a technique for receipt of a DMB signal through an IP-based wired/wireless network, a method of IP encapsulation of Motion Picture Expert Group-2 Transport Stream (MPEG-2 TS)/MPEG-4 Synchronization Layer (SL) DMB data and transmitting the IP-encapsulated DMB data has been developed.
In a retransmission system using a packet method for a DMB service, based on this development, a terminal supporting the packet method without having a separate DMB receiver can receive DMB data from a device having a DMB data decoding function and view a DMB program.
However, in the DMB data retransmission system, a retransmission server transmits only data having a MPEG-2 TS header extracted after performing error correction code from among information regarding DMB data via an IP-based wired/wireless network. Thus, an IP-based terminal must decode DMB data received from the DMB data retransmission system by analyzing a header of each received stream. Accordingly, a complicated process is required for the IP-based terminal to select a channel of DMB data to be received.
FIG. 4 is a flowchart illustrating a conventional channel change method of a terminal receiving retransmitted data in a retransmission system using a packet method for a DMB service.
Referring to FIG. 4, according to the conventional channel change method, packet type data transformed to IP-based data is received in step 41. If a Program Association Table (PAT) exists in the received packet type data in step 42, it is determined in step 44 whether a Program Map Table (PMT) according to the PAT exists in the received packet type data. If the PAT does not exist in the received packet type data in step 42, the relevant PAT is searched for in step 43, and it is determined in step 44 whether the PMT according to the found PAT exists in the received packet type data.
If it is determined in step 44 that the PMT exists in the received packet type data, it is determined in step 46 whether SL data exists in the received packet type data. If it is determined in step 44 that the PMT does not exist in the received packet type data, the relevant PMT is searched for in step 45, and it is determined in step 46 whether SL data according to the found PMT exists in the received packet type data.
If it is determined in step 46 that the SL data exists in the received packet type data, an Audio/Video (AV) packet according to the SL data is executed in step 48. If it is determined in step 46 that the SL data does not exist in the received packet type data, relevant SL data is searched for in step 47, and an AV packet according to the found SL data is executed in step 48.
That is, when a terminal receiving retransmitted data performs a conventional channel change in the retransmission system using a packet method for a DMB service, since all procedures of processing PAT, PMT, and SL data must be performed every time a channel is changed, the channel change operation is complicated and requires a long time.

Retransmission apparatus using packet method for DMB service

Maetan-Dong, Yeongtong-Gu Suwon-Si, Gyeonggi-Do


In one aspect, a temperature sensing assembly includes a thermowell, a temperature sensor, and at least one electrically conductive element. The thermowell includes a first gas impermeable barrier element defining a first chamber and a second gas impermeable barrier element defining a second chamber. The temperature sensor is at least partially disposed within the first chamber. The at least one electrically conductive element is connected to the temperature sensor in the second chamber.

Thermocouples are used in a variety of applications to sense temperature at a given location. A typical thermocouple comprises an external sheath and a pair of rod-shaped conductors disposed longitudinally within the sheath. Each conductor is of a dissimilar metallic material, and the two conductors are joined at a distal end within the sheath. An electrical insulation material also is packed about the rods within the sheath. The free ends of the conductors are connected to a detection instrument, such as a voltmeter, that measures the difference in potential created at the junction of the two metals. This difference in potential changes with temperature, thereby readily permitting the accurate detection of temperature at the junction point.
Thermocouples are used to measure the temperature of process fluids in a variety of industries, including, for example, the chemical, petroleum, and manufacturing industries. These thermocouples may be protected by a thermowell. Such thermowells are designed to be in the process flow and protect the temperature sensor from damage caused by direct contact with the fluid.

Gas impermeable temperature sensor protection system


A heat dissipating fabricated resistor grid for the dynamic braking of electric motors has a zigzag resistor supported by insulating members within a frame. The zigzag resistor is made up of a plurality of resistor elements formed from sheet metal, each element containing at least one "U" shaped bend, that are connected by welded joints between the legs of adjacent resistor elements. The resistor elements may be embossed to stiffen them. Various types of clips may be utilized to hold the tabs and the resistor elements together to facilitate welding and the clips are welded to the other components and become part of the zigzag resistor. Various types of connecting joints are provided to connect the zigzag resistor to the insulating members. Various types of securing devices are provided to secure the insulating members to a supporting metal frame.

1. Field of the Invention
This invention relates to electrical resistor assemblies incorporating a plurality of forced ventilated resistor grids that are used in the dynamic braking or retarding function of large electric motors such as the direct current traction motors on diesel electric locomotives. The resistor grid of the present invention has a zigzag resistor that is formed from a plurality of resistor elements that are connected to each other by welded joints of various types.
During dynamic braking of a diesel electric locomotive, its traction motors operate in a generating mode and supply current to heavy duty resistor grids where the electrical energy is converted to heat and dissipated to the atmosphere with the aid of cooling fans. The zigzag resistor elements must be able to withstand the high temperatures and vibration inherent in being utilized on locomotives. Further, in order to be economically useful, the resistor grids must be efficiently assembled and be easily replaceable in use.
2. Description of the Prior Art
Conventionally, the resistor element within the resistor grid is made up of a folded or zigzag strip or strips of resistance material mounted in the grid frame. The resistor strip may be a unitary fan folded strip as is shown in U.S. Pat. No. 4,100,526 and U.S. Pat. No. 4,651,124. The resistor element may also be formed from a series of short sections that are welded together as shown in U S. Pat. No. 4,651,125; U.S. Pat. No. 4,654,627; U.S. Pat. No. 5,068,637; and U.S. Pat. No. 5,049,852.
The present invention is directed to an improved resistor grid that has the zigzag strip made up of a plurality of resistor elements which are joined to each other by welded joints.

Resistor grid assembly having "U" bend resistor elements


An apparatus for suspending lamellar sun-blinds or the like, which apparatus comprises a profile open on at least one side with guiding, wherein a number of carriers (5) each having a gear transmission (8) and movable along the guiding by means of a control means, a control rod (11) arranged rotatably in and parallel to the profile, which is carried in each case through one of the gears of the transmission (8), a vertical rotating pin (7) with depending member for the slat connected to another gear and supported by the carrier, a spacer strip (66) connected to each of the carriers (5) which is guided slidably in a guiding of the adjacent carrier, wherein the spacer strip (66) is fixed on the side of the carrier such that the blade of the strip is vertically oriented in order to provide a profile dimensioning that is aesthetically well-considered, requires small dimensions particularly in the height and is thereby easy to combine with other profiles for additional applications.

Such an apparatus of the type described in the preamble is often used for closing off openings, for example window openings, to which end the slats are disposed regularly over the surface of the opening and brought into a more or less overlapping position by being rotated about a vertical axis. The disposing movement and the rotating movement can be performed independently of one another.
The slats are automatically disposed over the surface of the opening by placing one carrier at an interval from another carrier, this interval being determined by a stop on the spacer strip. As the carrier moves further each following carrier is taken along with it, this movement again being defined by the following spacer strip. The drawback to the known apparatus is that the track in which the carriers are guided is relatively high, which does not improve the appearance of the whole curtain. The series of spacer strips stacked onto each other in any case requires a particular thickness, the dimension of which is added to the height of the carrier.

Apparatus for suspending lamellar sun-blinds or the like


A touchpad module includes a touch member, a bracket, a piezoelectric vibration unit and an elastic element. The bracket is located under the touch member. A portion of the touch member is exposed to a first perforation of the bracket. The piezoelectric vibration unit is aligned with the first perforation of the bracket. The piezoelectric vibration unit has a first surface and a second surface, which are opposed to each other. The elastic element installed on the bracket and contacted with the second surface of the piezoelectric vibration unit. When the piezoelectric vibration unit vibrates, a first reaction force is generated between the first surface of the piezoelectric vibration unit and the portion of the touch member exposed to the first perforation, and a second reaction force is generated between the second surface of the piezoelectric vibration unit and the elastic element.

With increasing development of science and technology, a variety of electronic devices are designed in views of convenience and user-friendliness. For helping the user well operate the electronic devices, the electronic devices are gradually developed in views of humanization. The common electronic devices include for example notebook computers, mobile phones, satellite navigation devices, or the like. Recently, the storage capacity and the processor's computing performance for these electronic devices are largely enhanced, and thus their functions become more powerful and complicated. For efficiently operating an electronic device, a touchpad module is used as an input device of the electronic device for controlling the operations of the electronic device.
The touchpad module is usually installed on a casing of a notebook computer. Moreover, at least a part of the touchpad module is exposed outside the casing. Consequently, the touchpad module can be touched and operated by the user. For example, when the user's finger is placed on the touchpad module and moved on the touchpad module, a cursor shown on a display screen of the notebook computer is correspondingly moved. Alternatively, the user may press down the touchpad module to have the notebook computer execute a specified function. In other words, the touchpad module can be used to replace the mouse. Since it is not necessary to additionally carry or install the mouse, the use of the touchpad module is convenient.
Generally, the touchpad module comprises a hinge structure, a triggering part and a touch member. The hinge structure is located at two opposite sides of an inner surface of a fixing frame in the notebook computer. The touch member is connected with the hinge structure. Consequently, the touch member can be swung relative to the triggering part by using the hinge structure as a fulcrum. As the touch member is swung, a switch element under the touch member pushes against the triggering part. Consequently, the switch element is triggered to generate a switch signal to the notebook computer. According to the switch signal, the notebook computer executes a corresponding function.
However, the conventional touchpad module still has some drawbacks. For example, the region of the touch member that is aligned with the hinge structure cannot be pressed down, but only the region of the touch member that is not aligned with the hinge structure can be pressed down. In other words, the touch member of the touchpad module can be locally pressed down. Due to the structural design of the touchpad module, it is unable to press down the whole surface of the touch member.
For solving the above drawbacks, a haptics trackpad module capable of performing the full area pressing action has been proposed. The haptics trackpad module comprises a force sensor. For example, the force sensor is a capacitive-type force sensor, a resistive-type force sensor or a strain gauge force sensor. The force sensor is used to detect the input action of the user. Moreover, in order to expand the interaction between the haptics trackpad module and the user, the internal portion of the haptics trackpad module is further equipped with a haptics feedback element. The haptics feedback element is used to allow a portion of the haptics trackpad module to vibrate. The feedback or interaction purpose is achieved when the user feels the vibration. In accordance with the existing technology, the haptics trackpad module is equipped with a piezoelectric vibration element to generate the vibration. Consequently, the haptics trackpad module has the haptics feedback function.
However, the structure of the conventional haptics trackpad module still has some drawbacks. For example, only a specified surface of the piezoelectric vibration element is attached on the touch member. Consequently, when the piezoelectric vibration element vibrates the touch member, only a reaction force from the touch member is applied to the piezoelectric vibration element. Under this circumstance, the acceleration of the vibration generated by the piezoelectric vibration element cannot be effectively increased, and thus the vibration tactile feel is usually unsatisfactory to the user.
Therefore, there is a need of providing an improved touchpad module in order to overcome the above drawbacks.

Touchpad module and computing device using same


Devices and methods enable optimizing a signal of interest based on identifying and analyzing the signal of interest based on radio frequency energy measurements. Signal data is compared with stored data to identify the signal of interest. Signal degradation data is calculated based on noise figure parameters, hardware parameters and environment parameters. The signal of interest is optimized based on the signal degradation data. Terrain data may also be used for optimizing the signal of interest.

Spectrum management may be the process of regulating the use of radio frequencies to promote efficient use and gain net social benefit. A problem faced in effective spectrum management is the various numbers of devices emanating wireless signal propagations at different frequencies and across different technological standards. Coupled with the different regulations relating to spectrum usage around the globe effective spectrum management becomes difficult to obtain and at best can only be reached over a long period of time.
Another problem facing effective spectrum management is the growing need from spectrum despite the finite amount of spectrum available. Wireless technologies have exponentially grown in recent years. Consequently, available spectrum has become a valuable resource that must be efficiently utilized. Therefore, systems and methods are needed to effectively manage and optimize the available spectrum that is being used.
Most spectrum management devices may be categorized into two primary types. The first type is a spectral analyzer where a device is specifically fitted to run a 'scanner' type receiver that is tailored to provide spectral information for a narrow window of frequencies related to a specific and limited type of communications standard, such as cellular communication standard. Problems arise with these narrowly tailored devices as cellular standards change and/or spectrum use changes impact the spectrum space of these technologies. Changes to the software and hardware for these narrowly tailored devices become too complicated, thus necessitating the need to purchase a totally different and new device. Unfortunately, this type of device is only for a specific use and cannot be used to alleviate the entire needs of the spectrum management community.
The second type of spectral management device employs a methodology that requires bulky, extremely difficult to use processes, and expensive equipment. In order to attain a broad spectrum management view and complete all the necessary tasks, the device ends up becoming a conglomerate of software and hardware devices that is both hard to use and difficult to maneuver from one location to another.
While there may be several additional problems associated with current spectrum management devices, the problems may be summed up as two major problems: 1) most devices are built to inherently only handle specific spectrum technologies such as 900 MHz cellular spectrum while not being able to mitigate other technologies that may be interfering or competing with that spectrum, and 2) the other spectrum management devices consist of large spectrum analyzers, database systems, and spectrum management software that is expensive, too bulky, and too difficult to manage for a user's basic needs.

This patent is subject to a terminal disclaimer.

Systems, methods, and devices for electronic spectrum management


A method for operating a gas turbine engine includes channeling compressed air from the gas turbine engine to a noise suppression system, and selectively operating the noise suppression system such that air discharged from the noise suppression system generates a streamwise vortex downstream from each respective chevron.

This invention relates generally to gas turbine engines, and more particularly to methods and apparatus for operating gas turbine engines.
At least some known gas turbine engines include a core engine having, in serial flow arrangement, a fan assembly and a high pressure compressor which compress airflow entering the engine, a combustor which bums a mixture of fuel and air, and low and high pressure rotary assemblies which each include a plurality of rotor blades that extract rotational energy from airflow exiting the combustor.
Combustion gases are discharged from the core engine through an exhaust assembly. More specifically, within at least some known turbofan engines, a core exhaust nozzle discharges core exhaust gases radially inwardly from a concentric fan exhaust nozzle which exhausts fan discharge air therefrom for producing thrust. Generally during engine operation, both exhaust flows approach their maximum velocity during high power engine operations, such as during take-off operations. During such operations, as the high velocity flows interact with each other and with ambient air flowing past the engine, substantial noise may be produced along the take-off path of the aircraft.
To facilitate reducing such noise, at least some known turbine engine exhaust assemblies utilize noise suppression equipment which includes at least one of tabs, mixing lobes, and/or a plurality of chevrons to enhance mixing the core and bypass exhaust flows. Although the tabs, mixing lobes, and chevrons facilitate suppressing noise during high power engine operating conditions, because the tabs, mixing lobes, and chevrons are mechanical devices which remain positioned in the flow path during all flight conditions, such devices may adversely impact engine performance during non-take-off operating conditions. Specifically, during cruise conditions, the tabs, the mixing lobes, and/or the chevrons may adversely impact specific fuel consumption (SFC) of the engine.

Methods and apparatus for operating gas turbine engines


A steering wheel is provided that is able to prevent damage to a layer adjacent to an outer surface layer due to an external force applied when a joined portion between outer surface layer material parts is finished.

In recent years, there has been a widespread use of steering wheels that are provided with a conductive layer located between an outer surface layer and a core metal and can detect whether or not a driver grips the rim portion.
For example, Japanese Patent Application Publication No. 2019-202446 discloses a steering wheel that is provided with a conductive layer made of an elastic body located between an outer surface layer and a core metal of a rim portion and that detects whether or not the driver grips the rim portion based on a change in an electrostatic capacitance between the hands of the driver and the elastic body layer while ensuring flexibility.

Abstract: In a steering wheel comprising a rim portion having a core metal and a covering portion 5 covering the core metal, and a mat material 6 provided between an outer surface material 9 and the covering portion 5 of the rim portion and having a conductive portion 7 on a part facing the outer surface material 9, and the outer surface material 9 has a joined portion 91 formed in a direction intersecting a circumferential direction of the rim portion, the covering portion 5 is provided with a groove 51 in which the joined portion 91 and a part of the mat material 6 are housed, and between the outer surface material 9 and the conductive portion 7, a sliding member 8 is interposed at least in a vicinity of the joined portion 91.


A NiTi alloy root canal file with a flexibility gradient includes a tip segment (F1), a middle segment (F2) and a root segment (F3) divided along the axis of the NiTi alloy root canal file with the flexibility gradient. The internal microstructure of the tip segment (F1) of the root canal file is martensite M-phase, the internal microstructure of the middle segment (F2) is R-phase, and the internal microstructure of the root segment (F3) is austenite A-Phase. The present invention further provides a manufacturing method for the NiTi alloy root canal file with the flexibility gradient. The beneficial effect of the present invention is effectively improving safety in use.

Root canal files, as the main dental instruments, have the functions of thoroughly cleaning the interior and inner wall of diseased root canals, removing diseased tissues and shaping a complete and smooth inner cavity of root canals.
The working segment of a root canal file has a certain cross-section shape, outer contour thereof has a specific coned shape, and is provided with a helical cutting edge, as shown in FIG. 1.
The root canal file instrument makes a rotary motion in root canal 1 at a certain speed during operation to cut the internal surface of the root canal for the purpose of the root canal cleaning and shaping, as shown in FIG. 2. Since the root canal generally has an inversely conical curved structure, the root canal can be divided into three sections according to its structure, i.e., upper segment C1, middle segment C2, and apical segment C3, and the root canal is curved remarkably in the middle segment C2 and apical segment C3. During the formation of the root canal, the amount of stock removal of the upper segment C1 is maximum, the middle segment C2 has a smaller amount of stock removal than that of the upper segment C1, and the apical segment C3 has the minimum amount of stock removal. FIG. 3 is a partial enlarged view of FIG. 2, in the drawing, 2 is the part that will be cut and removed during the shaping of the root canal, 3 is the axis of the original root canal, and 4 is the axis of the shaped root canal.
To thoroughly clean the interior of the root canal, especially the apical segment C3, the root canal file should be inserted thoroughly into the bottom of the root canal during operation. Due to the constraint of the curved root canal, the root canal file is subjected to high frequency alternating bending deformation during the operation.
In consideration of usability and safety, an ideal root canal file shall meet at least three requirements. Firstly, the root canal file shall have a continuous transitional flexibility to adapt to the curve of the root canal, and to make the tip of the root canal file reach the bottom of the root canal smoothly, so as to clean and shape the apical segment, and meanwhile prevent the generation of steps or lateral perforation on the inner wall of the root canal. Secondly, the root canal file shall have a certain cutting capacity so as to effectively remove diseased tissues and complete root canal shaping. Thirdly, the root canal file shall have a long resistance-to-bending fatigue fracture life to prevent fracture of the root canal file during use and further avoid medical accidents.
Traditional root canal files mainly include stainless steel root canal files and super-elastic NiTi alloy root canal files. The stainless steel root canal file has a good cutting property, but the high rigidity thereof is prone to cause steps and lateral perforation on the inner surface of the root canal, thereby unsatisfying the requirements for the curved root canal.
The NiTi alloy possesses excellent elasticity and good medical and biological properties, and is broadly applied in various medical instruments, including root canal files.
There are three types of phase structure of the microstructure of the NiTi alloy, i.e., austenite A-phase, martensite M-phase, and R-phase, respectively. Diffusionless transformation exists in the NiTi alloy and mutual transformation can occur between the various phases. The NiTi alloy can provide approximately 8% super-elasticity strain when the NiTi alloy is austenite A-phase. This super-elasticity originates from the stress-induced phase transformation between austenite A-phase and martensite M-phase. The NiTi alloy can provide approximately 8% shaping strain when the NiTi alloy is martensite M-phase. This shaping deformation originates from the re-orientation of twin substructure of martensite M-phase. Moreover, the NiTi alloy can provide approximately 1% shaping strain when the NiTi alloy is R-phase, and when continuously performing deformation, approximately 5% super-elasticity strain can be provided. The shaping deformation of R-phase originates from the re-orientation of R-phase substructure, and the super-elasticity strain of R-phase originates from the stress-induced phase transformation between R-phase and martensite M-phase.
Currently, three types of NiTi alloy root canal files are disclosed, which are super-elastic NiTi alloy root canal files, shape memory NiTi alloy root canal files, and segmented root canal files having both super-elasticity and shape memory properties, respectively.
The microstructure of the working segment of the super-elastic NiTi alloy root canal file is fully austenite A-phase under working temperature (human body environment temperature of 37° C.). When the root canal file is bent and deformed under stress during use, stress-induced martensite phase transition occurs inside the root canal file, namely, A to M phase transition. Once the stress is removed, M to A phase transition occurs, and the shape of the root canal file recovers, exhibiting super-elasticity behaviors. Such root canal file has a high strength and an excellent cutting property. However, large deformation resistance is required for elastic bending deformation, thus, it is hard to avoid the serious deviation of the axis of shaped root canal from the axis of the original root canal especially in segment C2. Furthermore, the generation of steps and lateral perforations of the root canal are prone to be caused, especially in segment C3. Besides, the interior microstructure of root canal file repeatedly undergoes periodic phase transition from A to M and from M to A during use. This phase transition process can generate some crystal defects such as dislocation. More and more crystal defects accumulate inside the material as the periodic deformation is repeated, which finally causes the fracture of the root canal file, shortening the resistance-to-bending fatigue life of the super-elastic NiTi alloy root canal file.
The microstructure of the working segment of the shape memory root canal file is fully martensite M-phase under working temperature (37° C.). Such root canal file does not have elasticity, but due to the small bending deformation resistance of shaping deformation, the root canal file is extremely flexible. The deformation mechanism of the root canal file mainly depends on re-orientation of the substructure of M-phase, no crystal defect occurs in the deformation of M-phase, therefore, the resistance-to-bending fatigue life of such root canal file is extremely long. The root canal file with fully martensite M-phase has extremely good flexibility, thus, effectively avoiding the generation of steps and lateral perforation on segment C3 of the root canal during shaping of the root canal. However, since the deformation resistance of M-phase is small, the cutting capacity of such root canal file is very poor, especially, it is difficult to cut segments C1 and C2 of the root canal. Meanwhile, since such root canal file is extremely flexible, distortion deformation along the axis direction easily happens to cause failure of the root canal file, which shortens the working life.
The front segment of the working segment of the segmented root canal file having both super-elasticity and shape memory properties is martensite M-phase, and the rear segment thereof is austenite A-phase under working temperature. The design objective of such root canal file is to endow the front segment with excellent flexibility and bending fatigue fracture resistant property, and endow the rear segment with excellent cutting property. Such an excellent design can effectively avoid the generation of steps and lateral perforation on segment C3 of the root canal, but certain problems still exist. If martensite M-phase segment is too long, though the fatigue life of the front segment of the root canal file is prolonged and the risk of lateral perforation of the root canal is reduced, the cutting efficiency to segment C2 of the root canal is pretty low, and the risk of failure of the root canal caused by axial distortion deformation of the martensite M-phase segment also exists. If martensite M-phase segment is too short, though high efficiency cutting on segments C1 and C2 of the root canal file can be achieved, like the super-elastic root canal file, serious deviation of the axis of the shaped root canal from the axis of the original root canal is easy to be caused, especially on segment C2.

NiTi alloy root canal file with flexibility gradient


A nozzle assembly with a directional flow passage for directing and controlling the flow of drilling fluids exiting a drill bit. The assembly is threaded for engagement within a threaded receptacle in the drill bit. The assembly includes a nozzle body carried within an externally threaded sleeve structure that threads into the bit receptacle. Seating of the assembly anchors the nozzle body against rotational and axial movement. The external circumferential nozzle body surface and the internal circumferential sleeve surface mechanically interlock to permit the nozzle body to be positioned at selected different angular positions within the sleeve before seating the sleeve structure in the receptacle such that the final seated position of the assembly in the receptacle results in the desired orientation of the nozzle flow passage in the bit receptacle. The flow passage exit end of the nozzle is surrounded by a drive area that extends axially from the main nozzle body. A conventional socket drive tool engaging the drive area is employed to rotate the nozzle and surrounding threaded sleeve structure into or out of engagement with the threaded receptacle.

1. Field of the Invention
The present invention relates generally to drilling well bores through the earth with a rotary drill bit. More specifically, the present invention relates to the structure and use of a nozzle employed to direct and control the flow of drilling fluids exiting from a drill bit.
2. Brief Description of the Prior Art Background of the Invention
Wells drilled in the earth are commonly formed with the use of a rotating drill bit positioned at the bottom of a tubular drill string. Rotation of the bit progressively cuts away the earthen formations engaged by the bit face to form a well bore. Drilling fluids pumped down the drill string to the bit exit the bit face through nozzles strategically disposed in the bit body. The fluid is used to clean, cool and lubricate the bit and assist in breaking away the formation. The fluid also serves to maintain pressure equilibrium within the well bore and carry formation cuttings back to the well surface.
Proper operation of the bit requires that the drilling fluid exit the bit with a flow pattern and velocity that are suited for a given bit design, as well as the anticipated well drilling environment. Nozzles carried in the drill bit function to direct and control the flow path and the pattern and velocity of the drilling fluids exiting the bit.
Drill bit bodies are customarily provided with internally threaded nozzle receptacles that can receive externally threaded nozzle bodies having a desired jetting characteristic. With conventional, non-directional nozzle bodies, the final angular orientation of the nozzle body once seated in the bit receptacle does not affect the proper operation of the fluid jetting action of the nozzle. However, where the fluid is to leave the nozzle at an angle relative to the nozzle axis, the final angular disposition of the nozzle within the receptacle determines the direction of flow of the exiting fluid over the bit body.
A nozzle having a directional exit flow pattern must remain firmly anchored within the nozzle receptacle after its installation so that it does not move axially or angularly during use. One technique for preventing such movement is to cement the nozzle within the receptacle at the desired axial and angular position. This technique suffers various shortcomings including the possible failure of the cement to properly retain the nozzle in place as well as the difficulty encountered in removing and replacing the nozzle after it has been cemented within the receptacle.
Proper final orientation of the nozzle in a threaded receptacle can be achieved by exactly matching the external threaded surface of the nozzle to that of the thread pattern in the receptacle such that the nozzle is seated and can no longer be rotated at the precise orientation producing the desired exit flow direction. One of the problems encountered in attempting to time the nozzle thread pattern to that of the receptacle threads relates to the need to form a precisely developed thread on the external surface of the nozzle body. The nozzle is desirably constructed from an extremely hard material such as tungsten carbide that is very difficult to machine. For this reason, nozzle assemblies are frequently constructed as multi-part components that include a tungsten carbide body and a surrounding steel sleeve with the threads machined into the softer steel material of the sleeve.
In some of the prior art designs, the sleeve is brazed or otherwise bonded to the nozzle body to prevent relative rotation between the two components. This technique can permit the nozzle and receptacle thread patterns to be timed with the nozzle flow direction so that the final seated position of the nozzle produces the desired orientation of the exit flow path from the bit. Use of this technique requires that each nozzle and sleeve assembly be bonded to be used in a specific matching receptacle. The technique is also limiting in that it is necessary to perform a bonding step immediately before the nozzle is installed, making field installations complicated and difficult. The use of shims to control the final seated position of the nozzle is also impressive and difficult to implement.
Some prior art nozzle bodies are formed by molding tungsten carbide to provide a single material body with an externally threaded surface. Creation of a precisely molded thread pattern that will meet with the internal threads of a specific nozzle receptacle such the final, seated position of the nozzle in the receptacle results in a predetermined orientation of the directional nozzle is also difficult to achieve. In general, techniques that require matching nozzle and receptacle threads in single body or bonded nozzle construction to determine final, seated orientation of a directional nozzle relative to the bit body are difficult and time-consuming.
The prior art includes a multiple-piece nozzle design in which an externally threaded, split sleeve closely surrounds a cylindrical nozzle body. The nozzle body may be angularly positioned within the sleeve before the assembly is placed in the receptacle so that the nozzle body is properly oriented when the nozzle and sleeve assembly is seated. This prior art design, described in U.S. Pat. No. 4,533,005 to Morrison, employs frictional force between the engaged, smooth internal cylindrical surfaces of the sleeve and nozzle body to hold the nozzle orientation once the nozzle has been seated in the receptacle. A specially configured tool is required to seat and extract the nozzle. The tool includes axially extending fingers that simultaneously engage aligned openings in the nozzle body and the threaded sleeve so that the two components of the nozzle assembly may be rotated as a unit. The fixed angular position of the nozzle is determined by rotating the nozzle within the sleeve to a selected angular position that will result in the desired final nozzle orientation when the sleeve is firmly seated within the nozzle receptacle.
While the Morrison prior art design offers improvements over the technique of cementing the nozzle within the receptacle, or attempting to match nozzle and receptacle thread patterns, the anchored nozzle of the Morrison design is susceptible to rotation during use because of the reliance on frictional engagement alone to prevent such rotation. Retaining the proper orientation of the nozzle body within the sleeve before the assembly is finally seated can also be difficult because of the slippage that may occur before the assembly is fully seated.
U.S. Pat. No. 4,794,995 to Matson describes a directional nozzle assembly that is held in place by an externally threaded sleeve. As with the Morrison design, the Matson design relies on frictional engagement between the sleeve and the nozzle body to prevent rotation of the nozzle within the sleeve.
A prior art nozzle design that employs a mechanical interlock rather than frictional engagement to prevent nozzle rotation is described in U.S. Pat. No. 4,776,412 to Thompson. The design employs a specially shaped bit receptacle having circumferentially spaced slots that mate with corresponding spaced nibs formed at the base of the nozzle body. A specially configured drive tool is employed to seat an externally threaded sleeve into the threaded receptacle and over the cylindrical nozzle body to hold the nozzle in the receptacle. Rotation of the nozzle is prevented by the interlocking engagement of the bit recess slots and the nozzle nibs. While the design is effective in preventing rotation of the installed nozzle, it is complex, requires a relatively large number of separate construction components, is difficult to build, and requires the use of a special drive tool.


A wire electric discharge machining apparatus that performs an electric discharge machining by applying a pulse voltage between a wire electrode (1) and a workpiece (2), the wire electric discharge machining apparatus including, a machining speed detection unit (14) that detects relative machining speed of the workpiece (2) and the wire electrode (1); a machining energy calculation unit (13) that calculates machining energy of a discharge pulse; a board thickness calculation unit (12) that calculates a board thickness of the workpiece (4) based on the machining speed detected by the machining speed detection unit (14) and the machining energy calculated by the machining energy calculation unit (13); a stationary state determination unit (16) that determines whether the machining is in a stationary state from a machining state during the machining, after the machining condition is switched in accordance with a board thickness of the workpiece (4) calculated by the board thickness calculation unit (12); and a machining condition switching unit (11) that switches the machining condition to a machining condition corresponding to a board thickness calculated by the board thickness calculation unit (12) when the stationary state determination unit (16) determines that the machining is in the stationary state and does not switch the machining condition to the machining condition corresponding to a calculated board thickness when the stationary state determination unit determines that the machining is not in the stationary state.

In general, in a wire electric discharge machining, when a board thickness of a workpiece is within a range of 40 to 60 mm, a wire breaking limit of a wire electrode is the highest, so that it is possible to set a machining condition having the highest machining energy.
This is because, although there is a limit on the machining current to be supplied to the wire electrode, as the workpiece becomes thicker, a current density per a unit wire electrode length becomes smaller, so that the wire breaking limit is increased. In the meantime, when the board thickness exceeds a threshold value, the effects of removing machining powders and cooling the wire electrode by a machining liquid are deteriorated, so that the wire breaking limit is lowered and thus the wire may be broken down.
In other words, as described above, the inputtable energy becomes maximum when the board thickness is within the range of 40 to 60 mm, and decreases as the board thickness becomes more distant from the range.
In machining the workpiece having different board thickness with a wire electric discharge machining apparatus, when the machining condition is set in correspondence to a board thickness portion having a high wire breaking limit, the wire breaks down when machining a board thickness portion having a low wire breaking limit, and when the machining condition is set in correspondence to a board thickness portion having a low wire breaking limit, the machining speed is lowered when machining a board thickness portion having a high wire breaking limit.
Accordingly, in order to efficiently machine the workpiece without the wire breaking by the wire electric discharge machining apparatus, it is necessary to set an appropriate machining condition in accordance with the change of the board thickness of the workpiece. Patent Document 1 discloses a technology of obtaining a board thickness of a workpiece by calculating a ratio of machining speed and machining energy and selecting appropriate machining conditions in accordance with the calculated board thickness, thereby efficiently performing an electric discharge machining.

Wire electric discharge machining apparatus


Lighting fixtures and lighting systems for use in areas with high magnetic fields or areas that require low EMI emissions. The lighting systems include a non-ferrous lighting fixture having an LED light source and a control circuit. The LED light source includes one or more LEDs, and the control circuit provides a regulated operational current to the LED light source. The control circuit includes at least one switch for controlling the flow of current through the control circuit. The switch has a first state and a second state, and the operational current provided to the LED light source is increased and decreased in a linear manner based on the state of the at least one switch.

This invention provides a quality white or other color light that can be used during operation of MRI equipment. This quality white or other color light can be dimmed to provide flexible lighting levels. The flexible lighting levels can range from the maximum light used for patient procedures and equipment servicing/maintenance to the lowest light level used to keep a patient comfortable while facing upward on the MRI scanning table.
Moreover, by using a thermally-conductive substrate printed circuit board, this invention resolves the thermal issues associated with the high-intensity light generated by multiple LED's. The thermally-conductive printed circuit board consists of an aluminum plate that is selectively coated with an electrical insulator (coating remains only where the electrical circuits will be formed) and then forming the electrical circuits using what is known as "fully additive" circuit processes. Thus, the aluminum substrate printed circuit board creates an isolation layer and, then, a conductive layer. These layers isolate the LED's electrically, but not thermally, from the heat sink. The aluminum plate provides a direct thermal connection to the high-intensity LED components.
The lighting level issues are resolved by the incorporation of a reflector around each LED and a diffuser lens located at the light fixture's opening. This combination makes the light softer, as well as more uniform and even. This combination also protects the user and installer from electrical hazards associated with the potentially high voltages within the light fixture itself
To date, no one has created such an MRI-compatible lighting system, and no other manufacture offers an LED lighting system for use in conjunction with operating MRI equipment.

LED lighting system for use in environments with high magnetic fields or that require low EMI emissions


An injection-locked frequency divider includes a signal injection circuit and colpitts VCO. The signal injection circuit is for injecting an injection signal. The colpitts VCO includes first and second transistors, first and second LC tank circuits and a cross-coupled transistor pair. The first terminals of the first and second transistors receive the injection signal. The first and second LC tank circuits are for determining resonance frequency of an oscillation signal of the colpitts VCO. The cross-coupled transistor pair includes third and fourth transistors. The control terminals of the third and fourth transistors are respectively coupled to first terminals of the fourth and third transistors. The first terminals of the third and fourth transistors are respectively coupled to a first terminal or control terminal of the first and second transistors for providing an equivalent negative resistance. The injection signal and oscillation signal are mixed in frequency to generate differential output signals.

1. Field of the Invention
The invention relates in general to an injection-locked frequency divider, and more particularly to an injection-locked frequency divider with a wide injection-locked frequency range.
2. Description of the Related Art
The frequency divider is one of the indispensable and essential components in the present wireless communication system, which is used for receiving an original signal and reducing the frequency of the signal by dividing it by one or a number of different values.
The injection-locked frequency divider is a commonly-used high frequency divider, which integrates a signal injection unit and a voltage controlled oscillator (VCO), such as a LC tank oscillator to divide the frequency of an injection signal.
However, the conventional injection-locked frequency divider has a very narrow injection-locked frequency range. If the injection signal has a frequency falling outside the injection-locked frequency range of the injection-locked frequency divider due to process or temperature variation, the injection-locked frequency divider will have malfunction. Therefore, how to design an injection-locked frequency divider with a wide injection-locked frequency range is a target for the relevant industrials to be engaged in.

Injection-locked frequency divider with a wide injection-locked frequency range

National Taiwan University of Science and Technology


The coaxial dipole antenna of the present invention has a ground tube made of metal and a coaxial cable. The ground tube has a hollow containing part that the coaxial cable passes through, and an end of the ground tube has a clamping part. The clamping part has a first clamping slice to clamp a jacket of the coaxial antenna and a second clamping slice to clamp a metallic mesh of the coaxial cable. Such coaxial dipole antenna can transmit energy with the coaxial cable. The elements of the coaxial dipole antenna are combined with each other by pressing. Therefore, the coaxial dipole antenna can be manufactured by automation, the product thereof can be increased, and the quality thereof can be controlled.

1. Field of the Invention
This invention relates to a coaxial dipole antenna manufactured with coaxial cable and ground tube through pressing, wherein an upper end is pressed with a jacket and a metallic mesh of the coaxial cable for fixing the cable, grounding, and transmitting energy.
2. Description of the Prior Art
Recently, the combination between electronic devices or between cables is almost conventional welding connection, and the process of antenna also employs welding connection. However, those processes in electronics industry nowadays trend toward unleaded process. Therefore, the conventional structure and process not only cause air pollution, but also break the antenna structure resulted form defective welding or high temperature.
For solving the problems mentioned above, the industries in the field develop low-pollution welding materials as the connecting medium. Unfortunately, any welding materials always causes pollution and hard to maintain in follow-up service, and the yield of finished products will be reduced. Therefore, the cost of welding, check, and product management will increase.


An LED lamp having a lamp housing including a lamp base capable of connecting to a source of electrical power and at least one LED lighting device having at least one LED, the lighting device being electrically connected to the lamp base offset from a center line running vertically through the center of the housing. The lamp further includes at least one optic having at least two sub-optics, each sub-optic capable of allowing a different beam angle of light distribution to pass there through when aligned with the LED lighting device, the optic being integrated with the lamp housing such that the optic may be rotated to align one sub-optic over the LED lighting device at a time.

LEDs are semiconductor devices that produce light when a voltage and current is supplied to them. LEDs are intrinsically DC devices that only pass current in one polarity. Historically LEDs have been driven by constant current or constant voltage DC. More recently, new inventions have demonstrated that LEDs may also be driven direct with low voltage AC or high voltage AC, and with low voltage and high voltage rectified AC.
The increasing adoption and advancement of LED technology has resulted in the development of new LED lighting devices and LED lamps which may replace legacy lamps or light bulbs. However, the known LED lamps use one or more LEDs with one fixed optic over each LED, a single optic over multiple LEDs, or a single LED with a single optic over the LED. These LED lamps do not provide a means of selecting more than one beam angle of light distribution from the LED lamps. Depending on location and use of an LED lamp, multiple beam angles may be needed depending on the surface, products or areas an end user desires to light by the lamp.
Furthermore, having to switch lamps to achieve a different beam angle regardless of the operational state of the lamp and lighting device within is inefficient and wasteful. LED lamps are typically more costly than legacy light bulbs or lamps and being unable to realize the full life of the lamp simple because a different desired beam angle is sought raises consumer costs and wastes operable LED lamps.
Rather than have to remove and replace an LED lamp having a different beam angle each time a new beam angle is desired or required, it would be advantageous to design an LED lamp having the capability to emit light in multiple beam angles.
The present invention is provided to solve these and other issues.


Substantially anhydrous nylon salts are made in a solid state process in which solid diamine carbamates are contacted and mixed with solid dicarboxylic acids in a near instantaneous reaction to produce the salt, and preferably are prepared by mixing the solid diamine carbamates and the solid dicarboxylic acids under conditions of high shear.

The present invention relates to the preparation of nylon salts from diamine carbamates and dicarboxylic acids. More particularly, the invention relates to a solid state process for making nylon salts by contacting a diamine carbamate and a dicarboxylic acid.
Poly(hexamethylene adipamide), commonly known as "nylon 6,6," is typically manufactured commercially by first making an aqueous salt solution from its monomers, hexamethylene diamine and adipic acid. The commercial diamine, which is generally about 85% by weight diamine and about 15% by weight water, is mixed with additional water so that the resulting hexamethylene diammonium adipate (nylon 6,6 salt) solution usually contains water in the range of about 50% by weight. This solution is then used as a starting material and initial reaction medium for the solution/melt polymerization of nylon 6,6.
Techniques are known for obtaining a nylon salt from the solution. One such technique comprises adding an organic liquid (e.g., isopropanol) in which the salt is not soluble, or only slightly soluble (i.e., a non-solvent for the salt). The addition of the non-solvent will cause the salt to precipitate. The salt is then recovered and dried. In this technique, however, not only must the precipitated salt be recovered, but also the organic liquid itself must be recovered. Instead of precipitating the salt, another technique to obtaining dry salt is to heat the solution and evaporate the water. However, both of these techniques require the use of additional energy and/or additional process steps and can be time consuming and costly.
The direct formation of the dry salt avoids this expense and complexity. See generally H. F. Mark, et al., Encyclopedia of Polymer Science and Technology, Vol. 11, John Wiley & Sons, Inc., New York, 1988, p. 362, and V. Hopp, et al., Handbook of Applied Chemistry, Hemisphere Publishing Corp., Washington, D.C., 1983, pp. IV/8-20, 8-21.

Preparation of nylon salts from diamine carbamates and dicarboxylic acids


A combination between a grinding ring and a grinding wheel is disclosed, wherein the grinding ring has a centrally defined hole, a tubular extension extending from a periphery defining the hole, an annular extension extending from an outer periphery of the tubular extension, a skirt formed adjacent to the annular extension, teeth formed by pressing at a joint between the annular extension and the skirt and barbs each formed on a free end of the teeth. The grinding wheel is made of cloth so that the teeth together with the bars are able to extend into the grinding wheel when the skirt is pressed and engagement between the grinding ring and the grinding wheel is enhanced by applying an adhesive.

1. Field of the Invention
The present invention relates to a grinding wheel in combination with a grinding ring, and more particularly to a grinding ring having multiple teeth formed on a peripheral edge of the grinding ring and a tubular extension centrally formed on a center of the grinding ring such that when the grinding ring is combined with the grinding wheel, extension of the teeth of the grinding ring into the grinding wheel is able to enhance the combining force therebetween.
2. Description of Related Art
A conventional grinding wheel assembly is shown in FIG. 15, which includes a grinding ring 10a and a grind wheel 20a. The grinding ring 10a is a shallow disk and has a central hole 11a, a tubular extension 12a extending from a peripheral edge defining the central hole 11a, a first annular extension 13a extending from an outer periphery of the tubular extension 12a, a flange 15a formed around an outer peripheral edge of the first annular extension 13a and a second annular extension 14a extending from an outer periphery of the flange 15a. The grinding wheel 20a has a hole 21a corresponding to the flange 15a. When the grinding ring 10a is to be combined the grinding wheel 20a, the flange 15a of the grinding ring 10a is extended into the hole 21a and an adhesive is applied to secure the engagement between the flange 15a and an inner periphery defining the hole 21a.
Another conventional grinding wheel assembly is shown in FIG. 16 of the attached drawings, which includes a grinding ring 30a and a grinding wheel 20a. The grinding ring 30a is a shallow disk and has a central hole 31a, a tubular extension 32a, an annular extension 33a extending from an outer periphery of the tubular extension 32a and teeth 34a formed on a peripheral edge of the annular extension 33a. When combining the grinding ring 30a and the grinding wheel 20a is necessary, the teeth 34a is inserted into the grinding wheel 20a and an adhesive is applied from the central hole 31a to secure the engagement therebetween.
A further conventional grinding wheel assembly is shown in FIG. 17 of the attached drawings, which includes a grinding ring 40a and a grinding wheel 50a. The grinding ring 40a is a shallow disk and has a central hole 41a, a tubular extension 42a extending from a periphery defining the central hole 41a, an annular extension 43a extending from an outer periphery of the tubular extension 42a and teeth 44a extending from a bottom face of the annular extension 43a, each tooth 44a having a barb 441a formed on a free end of the tooth 44a and a peripheral side 45a formed around the teeth 44a. The grinding wheel 50a is composed of multiple grinding plates 51a superposed on top of one another to form a circle. When the combination between the grinding wheel 50a and the grinding ring 40a is necessary, the teeth 44a is inserted into the grinding wheel 50a to allow the grinding ring 40a to cover all the grinding plates. Then an adhesive is applied from sides of the grinding ring 40a to securely engage the grinding plates of the grinding wheel 50a and combine the engagement between the grinding ring 40a and the grinding wheel 50a.
Although each of the grinding wheel assemblies initially has a firm combination between the grinding ring and the grinding wheel, there are still disadvantages making the combination unreliable, which are:
The grinding ring of FIG. 15 is made of plastic and has an area substantially the same as that of the grinding wheel. The adhesive seems the only solution to securely combine the engagement therebetween. Accordingly, the grinding ring is easily engaged with the polishing object and thus the surface of the polishing object is easily damaged. Further, the engagement between the grinding ring and the grinding wheel by the adhesive is not able to provide effective combining force and the grinding ring is easily fallen from the grinding wheel.
The grinding ring of FIG. 16 is made of metal such that using a mold to produce such a grinding ring with teeth formed on the periphery of the grinding ring. Besides, there is only the extension of the teeth into the grinding wheel to secure the engagement between the grinding ring and the grinding wheel, horizontal extension is not provided to the grinding ring such that when the grinding ring is polished, the grinding ring is easily broken due to lack of strength, which leads to a bad influence to the polishing surface of the object to be polished.
The conventional ring in FIG. 17 is made with a mold, temperature and pressure must be strictly controlled, resulting in high cost. Further, when the grinding ring is used with the grinding wheel having multiple grinding plates superposed together, the grinding ring is easily overturned due to lack of strength.
To overcome the shortcomings, the present invention intends to provide an improved grinding ring in combination with a grinding wheel.

Grinding wheel in combination with a grinding ring