A rolling gimbal harness for interconnecting between a gimbal mounted electronics assembly and a near gimbal electronics assembly in an airborne missile. The harness negotiates the dynamic range of the gimbal while exerting very little spring torque and friction. The harness is a flat ribbon of many shielded twisted wire pairs embedded in a highly flexible insulation material. The twisted wire pairs are terminated in very small connectors with pins having 0.025 spacing. The harness includes a pre-formed arcuate region which follows a circumferential path defined by the periphery of the gimbal platform.

In applications such as airborne missiles, for example, there is a need to conduct electrical signals between circuit assemblies which move in relation to each other. For example, missile guidance components can be mounted on a gimbal which has a dynamic range about a Y axis. It is necessary to provide a hard-wired electrical connection between the gimbal-mounted component and a circuit assembly which is mounted off the gimbal and is stationary. The problem is to provide a means of carrying the signals between the gimbal-mounted component and the stationary assembly as the gimbal is rolling and seeking a target, while complying with several requirements. These requirements include minimal space for the connection, a wide gimbal angle, and extremely tight spring torque and friction tolerances. In other words, the signal has to get to the gimbal-mounted component without imposing any physical restraint on the gimbal.
Conventionally, connections between electrical assemblies which move relative to one another are made by flexible harnesses which are relatively stiff. Moreover, these harnesses are made of twisted shielded wire pairs terminated in "Micro" connectors, wherein the pins are 0.050 inches apart, which are relatively large.
It would be an advantage to provide a cross gimbal harness assembly which is highly flexible.
It would further be advantageous to provide a cross gimbal harness assembly which incorporates very small connectors.


This invention relates to a method and apparatus for transmitting frequency shift key (FSK) data in packetized format. More particularly, the invention is directed to a method for using a new Real-Time Transport Protocol (RTP) payload type to transport FSK data used for voiceband data transmission outside of the voice RTP stream. This technique allows for data compression and reduces the possibility of packet loss for FSK data carried in-band.

This invention relates to a method and apparatus for transmitting frequency shift key (FSK) data in packetized format. More particularly, the invention is directed to a method for using a new Real-time Transport Protocol (RTP) payload type to transport FSK data used for voiceband data transmission outside of the voice RTP stream. This technique allows for data compression and reduces the possibility of packet loss for FSK data carried in-band.
While the invention is particularly directed to the art of data transmission for frequency shift key (FSK) data, and will be thus described with specific reference thereto, it will be appreciated that the invention may have usefulness in other fields and applications. For example, the invention may be used where it is desirable and practical to packetize any form of data within an RTP payload.
By way of background, general requirements for voiceband data transmission can be found in GR-30-CORE, LSSGR: Voiceband Data Transmission Interface (FSD 05-01-0100), Issue 2 (December 1998), which is incorporated herein by reference. These requirements indicate how to set up and transmit voiceband data using continuous-phase binary frequency-shift-keying (BFSK or, more commonly, FSK). FSK is typically used to deliver caller identification (caller ID) information to analog line customer premises equipment (CPE) during normal ringing (on-hook transmission) and call waiting alerting scenarios (off-hook transmission). It is also used to deliver visual message waiting indication during suppressed ringing (on-hook transmission) scenarios. While these applications are not necessarily all-inclusive, they are a representative sampling of the most commonly used features implementing FSK data.
The FSK transmission rate is 1200 baud. A one (1) bit is represented by a 1200 Hz tone. A zero (0) bit is represented by a 2200 Hz tone.
In general, FSK voiceband data transmission is framed loosely by other voiceband signaling events. For example, caller ID delivery during normal ringing places the FSK transmission a minimum of 500 milliseconds into the silent interval between the first and second cycles of ringing. FSK transmission must complete a minimum of 300 milliseconds prior to the beginning of the second ringing on cycle. For caller ID delivery during call waiting alerting, FSK transmission must start between 50 and 500 milliseconds after completion of the CPE alerting signal (CAS) and the CAS acknowledgement sequence of voiceband tones.
For on-hook transmission, there is a preamble sequence of 300 bits "010101 . . . " followed by 180 mark bits (ones) and then the data. For off-hook FSK transmission there is an initial marker of 80 mark bits (ones) and then the data. There is no preamble sequence for off-hook transmissions.
GR-30-CORE imposes three generalized message formats for the data: Single Data Message Format (SDMF), Multiple Data Message Format (MDMF), and Generic Data Message Format (GDMF). For SDMF and MDMF, each byte of data is preceded by a space bit (zero) and followed by a zero to 10 mark bits (ones). Since there is typically only one mark bit per byte of data there are normally 10 bits per byte of transmitted data. Then there is an eight-bit checksum, which is followed by zero to 10 mark bits. For GDMF there is no structure or framing (i.e., space and mark bits) to the data and there is no checksum, but there are zero to 10 mark bits at the end of the data.
As such, there is variability to the FSK transmission itself. The transmission, thus, may have different states. In this regard, the FSK transmission may have a preamble only for on-hook transmission, different marker lengths, multiple message data formats, a variable number of mark bits between data bytes and, after the data for SDMF and MDMF, no checksum for GDMF. Additionally, FSK transmissions are somewhat delay sensitive in that they are framed by other signaling events.
As shown in FIG. 1, a network 10 includes a public-switched telephone network (PSTN) as having a circuit switch 14. Also shown is a digital loop carrier (DLC) 16 connected to the PSTN 12 and a residence or user site 18. As shown, the residence 18 includes a caller ID box 20 and a phone 22.
In this system, FSK data is typically transmitted in-line to the residence 18 from the PSTN 12 through the DLC 16 using conventional techniques. These conventional techniques result in the difficulties noted above, e.g., state difficulties and transmission delays. Moreover, the call including FSK data cannot be routed through an IP network before being transmitted to the residence because the FSK data would be lost as a result of compression techniques typically implemented in such networks, or because of the potential for packet loss in these networks.
The present invention contemplates a new and improved data transmission technique that resolves the above-referenced difficulties and others.

Method and apparatus for transmitting frequency shift key data in a packetized format


A method of making a repositionable transfer adhesive is provided. The method includes the steps of (a) providing a release liner having opposing first and second surfaces, the first surface having a release value of at least 10 grams per inch, as measured according to the Tape Release Test, lower than the second surface; (b) providing an adhesive composition comprising microsphere adhesive and a binder adhesive; (c) coating the adhesive composition on the first surface of the release liner such that the microspheres protrude from the binder adhesive; (d) drying the adhesive composition to yield a microsphere transfer adhesive; (e) winding the release liner such that the microsphere transfer adhesive is wound inwardly and the second surface of the liner contacts the microspheres; and (f) applying pressure to the second surface of the liner.

There are a variety of adhesive transfer tapes commercially available today. Typically, adhesive transfer tapes are made by coating an adhesive composition on a differential release liner, i.e., a double-sided release liner where both major surfaces of the liner contain a release coating. The adhesive is coated to the side of the liner with the higher release value. After the adhesive composition is dried, the adhesive coated release liner is wound into a roll to yield the transfer adhesive. When unwinding the adhesive transfer tape, the adhesive remains attached to the side of the liner with the higher release value.
In use, the transfer adhesive is unwound and laminated to backings, such as paper, film, and foam. The transfer adhesive has higher adhesion to the backings than to the release liner and thus is transferred from the release liner to the backings. Transfer adhesives provide an advantage in that they can be applied to heat sensitive, moisture sensitive, or solvent sensitive backings. Because of these sensitivities, an adhesive composition cannot be applied directly to such backings having the sensitivities recited. Transfer adhesives can also be applied to backings by converters and laminators who do not have adhesive coating capability.

Method of making a microsphere transfer adhesive


A soft elastomeric disc for removal of polymeric compositions from an underlying substrate. The disc is useful for removing decorative decals, stripes, graphics, emblems, protective moldings, paint and adhesive and is made from a filled elastomeric composition. The elastomeric composition is filled with a system that combines an organic lubricant and a non-abrasive particulate.

Surface coverings such as decorative decals, stripes, graphics, emblems, and protective moldings are used extensively in a variety of applications. These surface coverings are typically adhered with pressure-sensitive adhesives to painted and unpainted surfaces of automobiles, trucks, airplanes, and boats. The pressure sensitive adhesives typically are based on acrylic polymers or elastomers which may have been modified by the addition of tackifiers and stabilizers to enable the surface covering item to adhere to the surface by finger or roller pressure.
In the process of repairing and repainting portions of a painted surface to which the surface coverings are adhered, removal of the coverings may be necessary. Removal of relatively thin surface coverings such as decals and pinstripes is presently done by removing the covering from the painted surface with a hand- or tool-held razor blade. Typically, this cutting process leaves the adhesive and small fragments of the surface covering on the surface which must thereafter be removed by vigorously rubbing the residue with a cloth or sponge soaked with a suitable solvent. Use of a razor blade may also damage the underlying surface paint.
Another removal procedure employs a heat gun to very carefully heat the surface covering so that a thin object such as a fingernail may be inserted under a softened edge to start removal and thereafter pulling on the edge to remove the remainder of the surface covering. However, relatively thin decals and stripes often do not have high tensile strength and usually tear free from the unremoved portion, thereby requiring the removal procedure to be initiated again. This procedure has the disadvantages of potentially overheating and damaging the painted surface from which the surface covering is removed, and it is a very tedious task.
Another existing problem occurs when emblems and protective side moldings on an automobile or truck are peeled from a surface. Adhesive residue is often left on both the emblem or molding and the painted surface of the automobile. The adhesive residue then must be removed from both surfaces, such as by vigorously rubbing the residue with a cloth or sponge soaked with a suitable solvent which is selected so that it will dissolve the adhesive residue but not harm the painted surface which bears it. While more aggressive solvents may facilitate faster removal of the adhesives, such solvents can damage some painted surfaces and may raise flammability and/or toxicity concerns. The adhesive residue on the emblem or the side molding must also be removed, usually by scraping, followed by solvent cleanup.
In response to these problems, systems have been developed that utilize a rotating polymeric disc. When the rotating disc is contacted with the surface covering, the resulting friction causes an increase in temperature. This temperature increase causes the adhesive to soften, and the emblem or molding can then be removed. An example of such a system is found in Winter, U.S. Pat. No. 5,269,874. Such systems have alleviated many of the above noted problems associated with the removal of adhered surface coverings. However, other concerns arise with rotating disc systems. For example, the hardness and abrasive properties of the disc must be controlled to ensure that the surface covering is removed without damaging the substrate. If the disc is too soft, insufficient heat will be generated and/or the disc material will smear onto the surface. If the temperature at the surface is too high, the underlying paint can be cracked or damaged, or airborne residue known as "fog" can be generated.

Portable apparatus for removing heat softenable surface coverings

Minnesota Mining and Manufacturing Company


A method for the rapid dilution of an aqueous peracid solution, particularly, peracetic acid, in which a concentrated peracid solution is diluted with an aqueous diluent to produce a more dilute peracid solution in which the solution components are already at equilibrium immediately after dilution. The peracid in a preferred embodiment of this method is peracetic acid, for which the aqueous diluent is acetic acid and water, or hydrogen peroxide and water, or acetic acid, hydrogen peroxide and water, whose relative amounts are selected to produce a diluted aqueous peracid acid solution whose peracetic acid, hydrogen peroxide and acetic acid components are in equilibrium immediately after dilution.

Peracetic acid, sometimes called peroxyacetic acid or PAA, is a well known chemical for its strong oxidizing potential. Peracetic acid has a molecular formula of C2H4O3 or CH3COOOH, a molecular mass of 76.05 g/mol, and a molecular structure as follows:

Peracetic acid is a liquid with an acrid odor and is normally sold in commercial formulations as aqueous solutions typically containing, e.g., 5, 15 or 35 wt % peracetic acid. Such aqueous formulations not only contain peracetic acid but also hydrogen peroxide (e.g. 7-25 wt %) and acetic acid (e.g., 6-39 wt %) in a dynamic chemical equilibrium.
Peracetic acid is commonly manufactured by reaction of acetic acid and concentrated hydrogen peroxide, often with an acid catalyst, e.g., sulfuric acid, in a semi-continuous process that optimizes reaction time versus high yields, yet typically proceeds for days:
The reaction rate is proportional to the concentration of the reactants present, so preparation of less concentrated solutions of peracetic acid, e.g., less than about 10 wt % peracetic acid and especially less than about 1 wt % peracetic acid, typically require extremely long reaction times of many days for the reaction to reach completion.
As a result of the reaction kinetics described above, dilute concentrations of peracetic acid are normally prepared by water dilution of more concentrated peracetic acid solutions. However, dilution of concentrated peracetic acid solutions with water usually results in the hydrolysis of some of the peracetic acid and its decomposition into acetic acid, which reduces the amount of available peracetic acid. In addition, equilibration of the peracetic acid in the diluted solution with the other components present, hydrogen peroxide, acetic acid and water in the aqueous solution, may require many hours, if not days, before an equilibrated solution is obtained.
Various dilution and/or reaction procedures for obtaining dilute peracetic acid solutions are described in the literature, with the objective of shortening the overall time required to obtain a dilute peracetic acid solution, as compared with direct reaction of dilute acetic acid (or acetic anhydride) with dilute hydrogen peroxide.
Greenspan et al., in Proc. 42nd Ann. Mtg. Chem. Spec. Man. Assn. December 1955, pp. 59-64, concerns peracetic acid aerosols useful in bacteriological applications and discloses that peracetic acid is considerably less stable than hydrogen peroxide. The reference teaches that dilute peracetic acid solutions present special stability problems and that dilute, e.g. 1%, peracetic acid solutions prepared by dilution of concentrated peracetic acid with water will hydrolyze, making them unsuitable for sale as commercial formulations. Greenspan et al. disclose that stable dilute peracetic acid solutions can be made by use of peracid stabilizers in conjunction with proper adjustment of the relative concentrations of the components of the dilute peracid solution but provide no examples. A typical peracetic acid formulation used in the aerosol work was said to contain 1.0% peracetic acid, 14.5% acetic acid, 5.0% hydrogen peroxide, 1.0% sulfuric acid and 78.5% water.
U.S. Pat. No. 4,297,298 of Crommelynck et al. discloses a two step process for the production of dilute solutions of peracids such as peracetic acid. The first step (in the case of peracetic acid) involves the production of concentrated peracetic acid from the reaction of acetic acid or acetic anhydride with concentrated hydrogen peroxide in the presence of a strong acid catalyst like sulfuric acid, which can take up to 48 hours. The second step involves diluting the concentrated peracetic acid reaction mixture with one or more of the reagents to a non-equilibrium concentration, to retard the catalytic effect of the strong acid catalyst. The diluted non-equilibrium reaction mixture still proceeds to form additional peracetic acid, albeit at a much slower rate.
U.S. Pat. No. 5,349,083 of Brougham discloses a two step industrial process for the production of dilute solutions of peracids such as peracetic acid. In the first step (in the case of peracetic acid) concentrated acetic acid is reacted with concentrated hydrogen peroxide, optionally in the presence of an acid catalyst like sulfuric acid, to produce a non-equilibrium concentration of peracetic acid. In the second step, the non-equilibrium reaction mixture is diluted with water or, less preferably, with water and quantities of acetic acid and/or hydrogen peroxide, to reproduce an equilibrated dilute peracetic acid solution. Although this process reduces the overall time to produce the dilute peracid solution, many hours are still required to produce the intermediate, non-equilibrium peracid solution that is subsequently diluted.
U.S. Pat. No. 5,368,867 of Da Silva et al. teaches the accelerated production of dilute equilibrated, storage stable solutions of peracetic acid by employing a two step procedure. In a first step, a concentrated peracetic acid solution is diluted with water and only partially hydrolyzed (in the presence of an acid catalyst); the hydrolysis reaction is not allowed to reach equilibrium. In a second step, the hydrolysis reaction is quenched by addition of hydrogen peroxide to yield a low concentration of peracetic acid, containing between 0.05-2.5 wt % peracetic acid. The advantage cited for this invention is the reduction in time necessary for obtaining a stable dilute solution, in equilibrium, of peracetic acid in low concentrations; the examples illustrate holding times of the order of 2-5 days, compared to much longer times (6 days or longer) required in previous prior art methods.
U.S. Pat. No. 5,977,403 of Byers discloses a two step process for the production of dilute solutions of peracids such as peracetic acid. In the first step (in the case of peracetic acid) acetic anhydride is reacted with concentrated hydrogen peroxide in the presence of an acid catalyst like sulfuric acid for less than 60 minutes, to produce a non-equilibrium concentration of peracetic acid. In the second step, the reaction mixture, which has not reached equilibrium, is diluted with water and hydrogen peroxide to produce peracetic acid at a concentration of about 0.5 to about 15.0 wt % that is at or near equilibrium.
There remains a need for a direct, fast and cost effective method for producing dilute equilibrated aqueous peracetic acid solutions from more concentrated peracetic acid solutions, avoiding the multi-step and time-consuming procedures of the prior art.

Rapid dilution of peracid solutions to equilibrated solutions


A transmitter and/or receiver includes a single crystal clock oscillator circuit and a sample rate converter (SRC) that selectively generates samples at an alternative frequency for subsequent transmission or decoding. A 40 MHz crystal provides the clock signal for the digital-to-analog and analog-to-digital converters that are used to convert the samples to and from analog form. In an IEEE 802.11-compatible embodiment, the 802.11a compatible 20 MHz OFDM samples are converted to and from analog form directly, whereas a sample rate converter converts the 802.11b compatible 22 MHz DSSS samples to and from 40 MHz samples to provide compatibility with the 40 MHz analog conversions.

1. Field of the Invention
This invention relates to the field of communications, and in particular to a radio receiver that is configured to receive either DSSS (Direct Sequence Spread Spectrum) or OFDM (Othogonal Frequency Division Multiplexing) communications.
2. Description of Related Art
The IEEE 802.11g specification calls for wireless communications systems that can communicate at higher data rates than conventional 802.11b devices, yet be compatible with such 802.11b devices. Within an 802.11g signal, both "serial" (802.11b-compatible DSSS) modulation and "parallel" (802.11a-compatible OFDM) modulation are employed.
IEEE 802.11b DSSS devices are configured to operate with a 'chip rate' of 11 Mega-chips-per-second (Mcps), and must be sampled at integer multiples of 11 MHZ, while IEEE 802.11a OFDM devices require a sampling rate of 20 Mega-cycles-per-second (MHz), or integer multiples thereof. Conventionally, dual clock-generating devices (typically crystal devices) are used to provide these sampling clock signals, and to provide the required analog-to-digital and digital-to-analog conversions of the sample streams at each sampling frequency.
PCT patent application PCT/US01/17525 "DUAL PACKET CONFIGURATION FOR WIRELESS COMMUNICATION", teaches the use of two clock sources for dual-mode wireless communications, and is incorporated by reference herein.
The referenced patent application also proposes a scheme wherein the transmission of dual-mode communications are based on a single clock source, thereby allowing a single clock source to be used at the receivers. In proposing this single-clock based system, however, the referenced patent notes that the resultant transmitted signals are not, per se, compatible with the existing 802.11a, 802.11b, and 802.11g specification.

Single oscillator DSSS and OFDM radio receiver


A neoplasm cell destruction device utilizing low frequency sound waves to disrupt or displace cellular materials in neoplastic cells so as to damage and ultimately destruct the neoplastic cells without destructing surrounding healthy cells and thereby eliminating the need for target finding apparatus. The device includes a plurality of signal generators, a controller, a plurality of amplifiers, a plurality of transducers, and a target interface. The controller is in electrical communication with, and generates timing and control signals for simultaneously activating, the plurality of signal generators. Each amplifier is in electrical communication with a respective signal generator and amplifies the signal generated by the respective signal generator so as to form an amplified signal. Each transducer is in electrical communication with a respective amplifier and is driven by the amplified signal formed by the respective amplifier. The target interface combines the waveform formed by the plurality of transducers to form an interference wave which is a low frequency sound wave.

1. Field of the Invention
The present invention relates to a biological cell destruction device. More particularly, the present invention relates to a neoplasm cell destruction device utilizing low frequency sound waves to disrupt or displace cellular materials in neoplastic cells so as to damage and ultimately destruct the neoplastic cells without destructing surrounding healthy cells by virtue of the neoplastic cells trading in their ability to heal themselves if damaged in return for uncontrollable reproduction whereas the healthy cells can repair themselves if damaged and thereby eliminating a need for target finding apparatus.
2. Description of the Prior Art
High frequency acoustic waves or ultrasound may be used to remotely heat industrial or biological materials. There has been strong evidence in research and clinical laboratories that focused ultrasound for cancer hyperthermia will become a useful mode of treating cancer patients, in addition to the surgical, radiological, and chemotherapeutic methods that are available now.
In the treatment of tumors in cancer hyperthermia, focused ultrasound heats the tumor to a temperature of approximately 43° C. while the adjacent healthy tissue is kept at a lower temperature, closer to normal body temperature (37° C.). The elevated temperature in the tumor disrupts the tumor growth and eventually kills it. This allows the cancer to potentially be treated without surgery, without ionizing radiation, or without chemotherapy.
Conventional focused ultrasound for heating is employed by using either a scanned ultrasound transducer or with a phased array. The scanned transducer uses a lens, much like an optical magnifying glass focus sunlight, while the phased array uses electronic delays among the array elements to achieve focusing. A burst of sound is then emitted which converges at the focus to provide localized high intensity acoustic energy. Some of the high energy acoustic energy is absorbed by the tissue at the focus and is dissipated as concentrated focal heat. The rest of the energy travels through the focus and is slowly dissipated into the surrounding tissues as distributed heat.
Biomedical hyperthermia applicators using a plurality of sound sources to heat larger, distributed volumes, have also been investigated. These investigations have relied upon linear thermal superposition of the plurality of sound sources to heat the target tissue. Nonlinear effects of sound propagation through animal tissue and materials have also been studied for a single sound source.
The nonlinear mixing, or intermodulation, of sound waves has been known in oceanographic acoustics. Oceanographic acoustic applications have used both the linear (superposition) and the nonlinear (intermodulation) effects of intersecting sound beams. Nonlinear acoustic sonars, known as oceanographic parametric sonars, deliberately promote the generation of a difference frequency to enhance sonar beam forming and long range sound propagation. The generated difference frequency is usually 30 to 60 dB below the level of the primary frequencies. A second product of nonlinear mixing is the sum frequency, which is generated by the intermodulation process at 10 to 40 dB below the level of the primary frequencies, indicating that the conversion from primary to sum frequency is a significantly more efficient process than the conversion of a primary to a difference frequency. Since higher frequencies are subject to higher absorption coefficients in water, they generate more heat than the primary frequencies as they propagate, but propagate shorter distances than the primary frequencies. In oceanographic sonar applications, heat generation via sound absorption is generally an undesirable result of nonlinear intermodulation.
It is generally recognized that the use of microwave energy to produce moderate internal heating is an effective tool in the treatment of tissue, especially neoplastic tumors. The primary factor limiting such treatment in the past has been the difficulty of delivering the heat to a target region below the skin surface. Of course, it is possible to use an interstitial source, but this method has the drawback of being invasive. Because of this limitation, noninvasive treatment to date has largely been confined to treatment of surface tumors since it is difficult to heat deep tumors without also heating the intervening tissue.
In order to get significant heating in tumors more than a few millimeters below the skin surface, the field from a single source at the skin surface will have to be high and therefore painful. One approach has used a moving source, generally activated by switching discrete sub-arrays of sources. The moving source, however, results in an incoherent summation of energy at the tumor site. While tending to reduce the heating effects in the intervening tissue, this method has not eliminated the heating of the intervening tissue or reduced it to an acceptable level.
Additionally, to insure that the desired volume of tissue is potentially heated, an operator must not only know the characteristics in the area of interest, but also be able to determine which tissues are being heated. Currently, the ability to make this determination depends on the use of an interstitial probe or a radiometer. The current method also does not allow for imaging of the area, except to use other modalities, such as CT, MRI, ultrasound, etc. Such methods, while noninvasive, do not provide appropriate characteristics of the area and tissue to maximize the heating of the target tissue with microwaves.
Most cancer cells during metastasis are rapidly killed by mechanical trauma, associated with shape-transitions, which requires increases in cell surface area. L. Weiss, J. P. Harlos, and G. Elkin; Int. J. Cancer 44; 143-148 (1989).
The hypothesis has been advanced that such increases in surface area occur in two phases. First, there is an apparent increase as a result of surface unfolding, which is reversible and non-lethal. Second, there is a true increase, during which cell surface membranes are stretched, with an increase in membrane tension. When tension exceeds a critical level, the surface membranes rupture and the irreversible change is lethal.
Numerous innovations for destroying biological tissues have been provided in the prior art that will be described. Even though these innovations may be suitable for the specific individual purposes to which they address, however, they differ from the present invention in that they do not teach a cancer cell destruction device utilizing low frequency sound waves to disrupt or displace cellular materials in cancerous cells so as to damage and ultimately destruct the cancerous cells without destructing surrounding healthy cells by virtue of the cancerous cells trading in their ability to heal themselves if damaged in return for uncontrollable reproduction whereas the healthy cells can repair themselves if damaged and thereby eliminating the need for target finding apparatus.
For example, U.S. Pat. No. 5,144,953 to Wurster et al. teaches a lithotritor with an X-ray alignment system that includes a transducer for generating focused ultrasonic shock waves adapted for alignment on a concretion or tissue to be destroyed. The transducer is connected to an image-forming diagnostic X-ray system for locating the concretion or tissue and includes an X-ray emitter and an image intensifier disposed on a pivotable frame. The transducer is connected to the X-ray emitter which in turn is disposed at the center of the transducer, so that the emission axes of the transducer and the X-ray emitter coincide.
Another example, U.S. Pat. No. 5,222,484 to Krauss et al. teaches an apparatus for shock wave treatment that includes a shock wave transducer with a cup-shaped body and with an X-ray location finding device for finding the location of a bodily concretion or tissue to be treated. The X-ray device includes an extendable X-ray tube with telescoping tube sections which are sealed against an acoustic coupling medium filling the delay path of the transducer by a balloon filling arranged within the X-ray tube. The balloon is secured to the upper section of the tube and to the lower section thereof. Over pressure or under pressure is applied to the interior of the X-ray tube to adjust its length in order to optimize X-ray location finding on the one hand, and shock wave treatment on the other hand.
Still another example, U.S. Pat. No. 5,388,581 to Bauer et al. teaches a therapy apparatus for treating concretions and tissue in the body of a patient by means of sound waves. The apparatus includes a sound wave generator and an available X-ray device for locating an object for therapy. The therapy apparatus has a spot film device that is arranged within the axial passage of an X-ray cone. The available X-ray device is attached to the sound wave generator, with its central longitudinal axis aligned with the focus thereof so as to be able to precisely adjust and fix the X-ray device to the therapy apparatus quickly and safely.
Yet another example, U.S. Pat. No. 5,498,236 to Dubrul et al. teaches a catheter suitable for introduction into a tubular tissue for dissolving blockages in such tissue. The catheter is particularly useful for removing thrombi within blood vessels. In accordance with the preferred embodiments, a combination of vibrating motion and injection of a lysing agent is utilized to break up blockages in vessels. The vessels may be veins, arteries, ducts, intestines, or any lumen within the body that may become blocked from the material that flows through it. As a particular example, dissolution of vascular thrombi is facilitated by advancing a catheter through the occluded vessel with the catheter causing a vibrating stirring action in and around the thrombus usually in combination with the dispensing of a thrombotic agent, such as urokinase into the thrombus. The catheter has an inflatable or expandable member near the distal tip which when inflated or expanded, prevents the passage of dislodged thrombus around the catheter. The dislodged portions of thrombus are directed through a perfusion channel in the catheter where they are removed by filtration means housed within the perfusion channel before the blood exits the tip of the catheter. Catheters that allow both low frequency (1-1000 Hz) vibratory motion and deliver of such agents to a blockage and a method for using such catheters are disclosed.
Still yet another example, U.S. Pat. No. 5,501,655 to Rolt et al. teaches an ultrasound hyperthermia applicator suitable for medical hyperthermia treatment, and method a for using it. The applicator includes two ultrasound sources producing focused ultrasound beams of frequencies f0 and f1. An aiming device directs the two ultrasound beams, so that they cross each other confocally at the target. A controller activates the two ultrasound sources, so that the target is simultaneously irradiated by the two focused ultrasound beams. The two ultrasound sources provide acoustic energy sufficient to cause sufficient intermodulation products to be produced at the target as a result of the interaction of the two ultrasound beams. The intermodulation products are absorbed by the target to enhance heating of the target. In preferred embodiments, the ultrasound sources include a pair of signal generators for producing gated ultrasound output signals driving single crystal ultrasound transducers. In other embodiments, the ultrasound sources include a pair of phased array ultrasound transducers for generating two separate ultrasound beams. An aiming device is provided for electronically steering and focusing the two ultrasound beams, so that they cross each other confocally at the target. Further embodiments employ pluralities of transducers, arrays, or both.
Yet still another example, U.S. Pat. No. 5,503,150 to Evans teaches a method and apparatus for noninvasively locating and heating a volume of tissue, specifically a cancerous tumor. The method includes placing a bolus in contact with the patient and substantially around an area of interest including the volume of tissue, placing an array of antennas on the bolus and substantially around the area of interest, imaging the area of interest, selecting an approximate center of the volume of tissue on the initial image, determining approximate amplitudes and phases for the antennas, energizing each element at respective appropriate amplitudes and phases to heat the volume of tissue, imaging respectively the area of interest to create subsequent images, and subtracting the initial image from the subsequent images to determine temperature changes in the area of interest.
Still yet another example, U.S. Pat. No. 5,524,625 to Okazaki et al. teaches a shock wave generating system capable a forming a wide concretion-disintegrating region by energizing ring-shaped transducers and a hyperthermia curing system. A width of a focused region synthesized from a plurality of focal points formed by a plurality of shock waves is varied by properly controlling delay times and/or drive voltages for a plurality of ring-shaped piezoelectric transducer elements. The shock wave generating system includes a shock wave generating unit having a plurality of shock wave generating elements and a driving unit for separately driving the plurality of shock wave generating elements by controlling at least delay times to produce a plurality of shock waves in such a manner that a dimension of a focused region synthesized from a plurality of different focal points formed by the plurality of shock waves is varied in accordance with a dimension of a concretion to be disintegrated which is present in a biological body under medical examination.
Finally, yet still another example, U.S. Pat. No. 5,542,906 to Herrman et al. teaches a therapy apparatus that has a source of acoustic waves which generates acoustic waves focused onto a focus and an X-ray locating means with which the subject to be treated can be irradiated from different directions. The central ray of the locating means assumes a first direction for a first irradiation direction and a second direction for a second irradiation direction. The apparatus has a positioning system with which the subject to be treated and the focus can be adjusted relative to one another. The region to be treated and the focus are adjustable relative to one another by synchronous actuation of the positioning system in two adjustment directions for at least one irradiation direction. The adjustment taking place in a direction that proceeds parallel to the direction of the central ray that belongs to the other irradiation direction.
It is apparent that numerous innovations for destroying biological tissues have been provided in the prior art that are adapted to be used. Furthermore, even though these innovations may be suitable for the specific individual purposes to which they address, however, they would not be suitable for the purposes of the present invention as heretofore described.

Neoplastic cell destruction device and method utilizing low frequency sound waves to disrupt or displace cellular materials


There is provided a lubricating method for a rolling bearing assembly capable of achieving a reliable lubrication and exhibiting a stable temperature rise. The method is for supplying a lubricant oil to the rolling bearing assembly during the operation thereof, in which in order to keep the temperature of a rolling bearing assembly (103) within a predetermined tolerance, the amount of the lubricant oil to be supplied during the operation is automatically or manually adjusted by means of a supply adjusting unit (102). Supply of the lubricant oil is performed in the form of an air/oil mixture by the use of a lubricant supply unit (101). The amount of the lubricant oil supplied varies depending on the rotational speed of the rolling bearing assembly (103). Change of the amount of the lubricant oil supplied depending on the rotational speed of the rolling bearing assembly (103) is carried out based on a result of sampling of data showing increase in temperature of the rolling bearing assembly (103) depending on the rotational speed thereof under a plurality of different lubricating conditions in which a different amount of the lubricant oil to be supplied is employed.

The purpose of lubricating rolling bearings is to prevent metallic rolling elements from directly contacting metallic inner and outer races of the rolling bearings by forming a thin oil film on rolling surfaces and sliding surfaces thereof. Lubrication when effected to the rolling bearings brings about the following merits:                (1) Minimization of friction and frictional wear,        (2) Removal of heat evolved as a result of friction,        (3) Increase of the lifetime of the rolling bearings,        (4) Prevention of rusting, and        (5) Prevention of foreign matter from being trapped in the rolling bearings.
In order to enhance those meritorious effects brought about by lubrication, it is necessary to adopt a lubricating method that is appropriate to the conditions under which the rolling bearings are used, to select a lubricant of a high quality and to design an appropriate sealing structure. Designing the sealing structure properly is required for removal of dusts contained in the lubricant, prevention of entrapment of foreign matter and avoidance of leakage of the lubricant.
In general, in the rolling bearing of a type used in rotatably supporting the machine tool spindle, the amount of lubricant oil used is extremely limited to a small value in order to minimize heat build-up resulting from stirring of the lubricant oil. FIG. 7 illustrates the friction loss and the bearing temperature relative to the amount of the lubricant used in such rolling bearing. As shown therein, the amount of the lubricant used is divided into five regions I to V In the lubricant amount region II, in which the temperature rise is lowest, an air/oil lubrication is employed.
In the air/oil lubrication, as shown in an example of the system in FIG. 8, the use is made of a reservoir 134 equipped with a level switch, a pump 135 and a solenoid valve 140 controlled by a timer 141 so that the lubricant oil can be metered accurately for each of the bearings 133 before it is supplied thereto at an optimum interval. After the lubricant oil has been mixed with air within an air supply tube 138 at a terminal end of an oil supply tube 136, the resultant air/oil mixture is jetted to a target portion of the rolling bearing 133 to be lubricated, by means of a nozzle 156 oriented towards such target portion. For this purpose, the air/oil lubricating system is largely employed as a lubricating method that is suitable to increase the rotational speed and lower the temperature rise of the machine tool spindle.
However, during the high speed rotation, the bearing temperature tends to increase, accompanied by lowering the capability of the lubricant oil to form an oil film. In addition, an air curtain formed by the air dragged to whirl around rotating elements of the rolling bearing 133 increases. Therefore, the higher the rotational speed, the more severe the lubricating condition, making it difficult for the lubricant oil, jetted from the nozzle 156, to get trapped inside the bearing 133. Because of this, the amount of the lubricant oil supplied in the air/oil lubricating system is so chosen as to secure a sufficient lubricant reliability during the maximum speed rotation.
With the air/oil lubrication, the amount of the lubricant oil to be supplied is determined in anticipation of the maximum speed rotation that requires the severe lubricating condition as discussed above.
On the other hand, during the low speed rotation, the bearing temperature is low and the capability of forming the air curtain which hampers the supply of the lubricant oil internally into the bearing is also low. For this reason, the lubricating condition is not so severe as that required during the high speed rotation, and the amount of the lubricant oil to be supplied is not required much. In other words, if the amount of the lubricant oil to be supplied to the rolling bearing 133 is determined so that an optimum lubrication condition can be obtained during the high speed rotation, such amount of the lubricant oil would become excessive during the low speed rotation. Since, with the air/oil lubrication, the amount of the lubricant oil falls within the lubricant amount region II in which change in temperature is extremely low, the bearing temperature will rise due to stirring drag if the amount of the lubricant oil to be supplied is excessive as described above.
The increase of the bearing temperature is also brought about by the following additional factors:
As an example of the air/oil lubricant supply, the inventor of the present invention has attempted to suggest a lubricating structure, in which not only is an outer peripheral surface of an inner race of a rolling bearing provided with an inclined surface area continued from a raceway surface of the inner race, but also a nozzle member is disposed along and spaced a predetermined distance from the inclined surface area so that the air/oil lubricant can be jetted from respective air/oil lubricant discharge ports of the nozzle member that are held in face-to-face relation with the inclined surface area. For the rolling bearing, an angular ball bearing or the like is used.
According to the suggested air/oil lubricating structure, the air/oil mixture, which is a lubricant oil mixed with a carrier air, is discharged from the air/oil lubricant discharge ports of the nozzle member and is then introduced into a gap between the inclined surface area of the inner race and the nozzle members. The air/oil mixture so introduced into the gap is subsequently guided into the bearing, being sucked by the effect of a negative pressure developed within the gap during the operation of the bearing, and further guided onto the raceway surface within the bearing and/or an inner peripheral surface of a ball retainer by the action of the surface tension of the lubricant oil, deposited on the inclined surface area of the inner race and a component of centrifugal force acting in a direction towards a large diameter portion of the inclined surface area.
As discussed above, since the air/oil mixture is supplied onto the inclined surface area of the bearing inner race and is not supplied directly onto the raceway surface along which rolling elements move, no wind sound resulting from revolution of the rolling elements is generated with the noise level consequently lowered. Also, since the lubricant oil is not supplied by an air spray, but the air/oil mixture supplied onto the inclined surface area of the bearing inner race is guided into the bearing by the effect of rotation of the bearing inner race, the air used merely serves to transport the lubricant oil to the inclined surface area of the bearing inner race and, therefore, the amount of the air used can be reduced. For this reason, the energy saving effect can also be expected as a result of reduction in the amount of the air used.
However, the above discussed suggestion has not led to disclosure of a specific angle of inclination appropriate for the inclined surface area of the inner race employed in the rolling bearing. In the air/oil lubricating structure such as suggested above, if the inclined surface area of the bearing inner race is designed with no regards paid to the angle of inclination, it has been found that the air/oil mixture deposited on the inclined surface area tends to be separated away from halfway the inclined surface area by the effect of the centrifugal force. Separation of the air/oil mixture away from halfway the inclined surface area of the bearing inner race leads to the incapability of the air/oil mixture efficiently reaching the rolling elements, resulting in lack of a sufficient amount of the lubricant oil. In such case, although it may be suspected that if the respective amounts of air and lubricant oil, both forming the air/oil mixture, are increased, the insufficient lubrication can be avoided, increase of the amount of the lubricant oil would bring about a risk of the increased stirring drag and the temperature rise. Where the bearing employing this air/oil lubricating structure is adopted to support, for example, a spindle device, increase of the bearing temperature brings about change in temperature of the spindle, thus affecting the precision of the spindle. Accordingly, it is necessary to avoid the unnecessary temperature rise by means of the efficient lubrication with a minimized amount of lubricant oil. Also, increase of the amount of air leads not only to increase of the energy consumption, but also a heavy load imposed on a compressor, which in turn increase the noises generated thereby.
Also, even where the above discussed air/oil lubricating structure is applied to such a cylindrical roller bearing 41 as shown in FIG. 24, if the angle of inclination of an inclined surface area 42b of an inner race 42 is not properly chosen, problems similar to those discussed above are unavoidable. In other words, a lubricant oil jetted onto the inclined surface area 42 and approaching a raceway surface 42a via the inclined surface area 42 will, after having reached a large diameter portion of the inclined surface area 42b as shown by the arrow A in FIG. 24, be separated from the inclined surface area 42b by the effect of the centrifugal force and will eventually be blocked off by an end face of a roller retainer 45 without flowing deep into an inner peripheral portion of the roller retainer 45. Because of this, the lubricant oil fails to reach within the interior of the bearing 41 and, hence, the bearing 41 will be lubricated insufficiently. Although even in this case the insufficient lubrication can be avoided if the respective mounts of air and lubricant oil are increased, increase of the amount of the lubricant oil appears to lead to increase of both the stirring drag and the temperature.

Method of and device for lubricating rolling bearings


An overhead transportation system includes a support structure positioning a running surface above ground level for operating a truck along the running surface. A car body is suspended from a beam or chassis carried by the truck in such a manner to place a center of rotation of the car body above the chassis and truck. Improved performance on curves is provided through superelevation of the tracks upon which fixed steel wheel assemblies of the truck ride.

Overhead-suspended systems are known in the art and currently in operation. Typically, car bodies are suspended directly from and below trucks. In one case the trucks have steel wheels running on top of a single steel rail, being truly a "Monorail". This allows the car bodies to swing out in curves but imposes limits on speed because of the suspension system. In another case, the trucks run inside a duct on rubber tires with side wheels to guide the non-steering rubber wheels with the car bodies suspended directly from the trucks. The roof of each car body typically serves as a rigid frame to which the trucks are attached. This fixes the distance between the trucks. The propulsion and braking forces generated in the trucks are limited as a result of the force being transmitted directly down to the car bodies through their suspension attachments.
In such cases the direct suspension of the bodies from the trucks results in difficulties when detaching or exchanging the car bodies. It also imposes limitations on the ability to couple vehicles into trains because such coupling is done at the car bodies and not at the trucks where the traction forces are generated.
As will be described for embodiments of the present invention, an Overhead-Suspended Light Rail (OSLR) system overcomes known limitations in typical overhead transport systems. The disadvantages that embodiments of the OSLR of the present invention can overcome include, but are not limited to the following herein presented, by way of example:
Light Rail Transit (LRT) uses tracks at grade level occupying land that is typically sterilized against other uses. In many places, the work of installing these tracks requires purchase of property, displacement of occupants, and disruption of commercial operations. In streets, it disrupts traffic movements for long periods of time. Especially costly is the needed utilities relocation. Cities that did not plan for a transit trench now require that whole drainage systems, natural gas, water service, telephone, cable TV and power be relocated. In mature cities the location of these is not accurately defined, thus creating expensive and hazardous conditions for workers. Embodiments of the OSLR of the present invention incorporates LRT technology but places tracks and train operations overhead, allowing existing land uses to continue without conflict and minimizes traffic interruption during construction. This avoids a need for new laboratory research, requiring that the system be engineered and installed only in an appropriate location.
LRT tracks and switches at grade are sensitive to climatic conditions such as snow, freezing rain and flooding from heavy rainstorms. The OSLR places the tracks, signals and power contact strips inside a covered duct with full protection from the weather.
LRT vehicles operating in the streets absorb traffic capacity from roadways already congested with other traffic. The vehicles become equally delayed because they cannot move any faster than this same congestion. They introduce risks of collisions, injuries and deaths with vehicles and pedestrians, and impose limits of permissible operating speeds. These risks of moving trains in the streets require that such vehicles be manually operated, preventing any prospect of full automation, with its associated economic and safe operation. There are strict limits on the lengths and speeds of trains in the streets, and on the frequency of trains, making it difficult to expand capacity to meet future growth. The OSLR herein described operates trains safely overhead and well separated from other operations and land uses on the ground, thus allowing full automation with train lengths and operating speeds free from speed restrictions typically placed at ground level.
Passengers and freight riding in LRT vehicles mounted above their wheels (bottom-supported) typically feel the shocks and lateral accelerations generated below them. Typical vehicle designs attempt to minimize this effect, but do not eliminate it. Passengers and freight in embodiments of the OSLR vehicles of the present invention ride below the wheels. Suspending the car body beneath a carrying vehicle effectively suspends the body like a pendulum, isolating it from lateral impacts sustained by the carrying vehicle and therefore affording a much smoother ride for passengers and freight.
Bottom-supported vehicles impose strict limitations on an amount of super-elevation to be tolerated on curves, directly impacting permissible speeds of vehicles traversing curves. The OSLR vehicles of the present invention avoid known constraints. As a result, greater super-elevation may be placed on curves, and the swing out of the car bodies enhances the effect to double the effective super-elevation allowing significantly faster operating speeds on the curves.
Further, there is a need for shorter journey times, for reducing the size of vehicle fleet required to fill any given operating schedule, for improving the productivity of the train equipment, and for marketing a quality of service superior to alternative systems and more attractive to the public.

Overhead suspended transportation system and method


A light-emitting device comprises: a substrate that holds one end of connection terminals and on which is mounted an electronic component; a light-emitting element that is mounted on one face of the substrate; a support member on which the substrate is mounted; and a cover section that positionally locates and holds the substrate, by mounting on the support member in a condition abutting one face of the substrate. The cover section has a cover section body that covers one face of the substrate; on the cover section body, a light guide is provided, through which passes the light that is emitted from the light emitting element, in a condition in which movement thereof is restricted along directions on either side of the substrate.

Heretofore, light-emitting devices that are provided with a light-emitting diode (LED) have widely been used to illuminate the passenger compartments of vehicles.
There has been proposed a technical idea that, in a light-emitting device of the above type, a lens (light guide) for covering an LED is disposed on the mounting surface of a board on which the LED is mounted, and a case is mounted on a connector while pressing an upper surface of the lens toward the board, thereby sandwiching and holding the lens and the board (see, for example, Japanese Laid-Open Patent Publication No. 2010-083210).
According to the invention disclosed in Japanese Laid-Open Patent Publication No. 2010-083210, however, since the board and the lens are sandwiched and held using the case and the connector, it is necessary to make the lens relatively strong. Consequently, the lens itself becomes large in size, and accordingly the light-emitting device becomes large in size and weight as a whole.
Japanese Laid-Open Patent Publication No. 2009-239255, for example, proposes a light-emitting device wherein a board is held in position with stress acting on a light guide being reduced. The light-emitting device is provided with a case and a cover fitting into the case. A board with a bombshell-shaped LED lamp mounted thereon is disposed in a chamber that is defined between the case and the cover, which sandwich the board therebetween.
Specifically, the case has a pair of confronting side walls having respective holes defined therein. The cover that is held in abutment against one surface (mounting surface) of the board has teeth fitted in the holes of the side walls. The side walls are joined by a wall having a lower end surface. Under a condition that the lower end surface abuts against the other surface of the board, the teeth are fitted in the holes, whereby the board is held.
Japanese Laid-Open Patent Publication No. 2009-239255 also discloses a technical idea wherein a tubular portion for inserting therein a rod-shaped light guide body (light guide) for guiding light emitted from the LED lamp is disposed in the case and the tubular portion has on an inner surface thereof a protrusion for positioning the light guide body, thereby keeping the distance between the light guide body and the LED lamp constant.


This invention discloses an apparatus and method for separating and feeding flat products from a stack to a gripper drum. The invention employs a specially-positioned pivoting and articulating sucker bar, having several degrees of motion, operating in timed relationship with a reciprocating and articulating pusher blade, to reduce the travel distance of vacuum suckers, to reduce the diameter of the gripper drum, and to increase the speed at which products are separated from the stack and transferred to the gripper drum.

1. Field of the Invention
This invention relates to an improved apparatus and method for separating flat products such as newspapers and inserts from a stack and feeding them to a drum or other moving machine parts at high speed.
2. Art Relating to the Invention
At present, machines for handling flat products, such as newspaper insert machines, often include one or more automatic feeders for feeding the products from a stationary stack to other moving parts of the machine. One item at a time is separated from the stack, either from the top or the bottom, and transferred to a rotating drum or other moving part by a separator device housed within a product feeder. Typically, one or more product feeders are mounted above a conveyor carrying open moving pockets, and the feeders transfer products from the drum into the pockets. An example of an insert machine is shown in U.S. Pat. No. 4,723,770.
If the flat products are thin or flexible, such as paper sheets or jackets, then several engineering challenges present themselves for proper and efficient machine operation. First, one item at a time must be separated from the stack without separating or damaging the remaining items. Since sheets of paper, for example, tend to stick together when stacked due to friction and air pressure, a means of separating one sheet from the stack sometimes includes a suction device to pull one sheet away while leaving the remaining sheets in place. After separation, the item must be transferred from the stationary stack to other parts of the machine that are moving, such as a rotating drum or a conveyor.
One example of a prior art separator and feeder apparatus is shown in FIG. 1. A hopper having a table 2 holds a stack of flat products 1. A reciprocating sucker bar 6 is pivotally mounted beneath the lowermost product in the stack. One or more suckers 5 are attached to one end of the sucker bar, and the bar pivots around its other end. Note that, in this prior art device, the pivot point of the sucker bar is situated directly underneath the table and the stack.
Beneath the hopper and the sucker bar, there is mounted a rotating drum 3, which carries one or more grippers 7 around its periphery. The grippers open and close at certain, timed positions as the drum rotates (counterclockwise in FIG. 1).
In operation, as an open gripper rotates up towards the hopper, sucker bar 6 pivots upward and suction is applied to the sucker 5. The sucker approaches and then makes contact with an edge portion of the lowermost product in the hopper. As used herein, this edge portion, which is the portion closest to the drum, is called the leading edge of the product.
Next, the sucker bar 6 pivots downward, causing sucker 5 to peel the leading edge of the lowermost product away from the leading edge of the next lowermost product in the stack by suction, and to bend the leading edge of the lowermost product downward. This creates a gap between the lowermost product and the next lowermost product. Meanwhile, the gripper 7 continues to rotate toward the stack. When the gripper moves into a position immediately below the bent-down leading edge of the lowermost product, the gripper closes and grabs the leading edge. Suction is then immediately released from the sucker 5, and the gripper then pulls the product down and around a portion of the periphery of the drum 3. Subsequently, the gripper opens and releases the product into a moving pocket 4, which carries the product away for further processing.
While the above-mentioned prior art separator and feeder apparatus accomplishes the task of separating one product from a stack of products and transferring it to a rotating drum, it has certain limitations that limit the speed of operation of the machine. For example, since the sucker bar is positioned underneath the stack in the prior art, in order for the sucker to clear the leading edge of the paper in time, the sucker bar must swing down (counterclockwise in FIG. 1).
In addition, in order for the sucker bar 6 to position the leading edge of the product accurately for proper pick-up by the gripper 7, the sucker bar must pivot all the way down, such that the "final," extended position of sucker 5 is almost touching the rotating drum. In other words, the distance that the sucker must "travel" is the entire distance between the bottom side of the lowermost product in the stack and the uppermost periphery of the drum. Since there are mechanical limits on how quickly the sucker bar can be pivoted back and forth, the necessity for the sucker to make a "full travel" limits the speed at which products can be separated from the stack and transferred to the drum. This full travel requirement also increases the amount of time that suction must be applied to the sucker, and also increases wear and tear on the sucker bar. In addition, this arrangement requires the drum to have a relatively large diameter, placing limits on the rotational speed of the drum. Consequently, the above disadvantages place an upper limit on the speed of the entire machine. It is desirable to overcome these limitations, particularly in machines such as newspaper insert machines, where extremely high speeds are required.


Provided are methods and systems for detecting formation of nucleotide-specific ternary complexes comprising a DNA polymerase, a nucleic acid, and a nucleotide complementary to the templated base of the primed template nucleic acid. The methods and systems facilitate determination of the next correct nucleotide without requiring chemical incorporation of the nucleotide into the primer. This advantageously improves signal-to-noise ratios and increases the quality of results obtainable in a sequencing-by-binding protocol, and enables extended read lengths. These results can even be achieved in procedures employing unlabeled, native nucleotides.

Accurate sequence determination of a template nucleic acid strand finds many important applications in genomic analysis, molecular diagnostics, and the like. Even identification of a single nucleotide base from among alternatives at a known position can serve as the basis for analysis of single nucleotide polymorphisms (i.e., "SNPs"). Detection of short stretches of known nucleic acid sequence has been used for identifying bacterial, fungal, and viral pathogens from clinical or environmental sources. Detecting inherited or acquired genetic variants (e.g., changes or mutations) in known nucleic acid sequences also provides important information, for example having to do with changed susceptibility to certain medications. Finally, sequencing on the genomic scale depends on correct identification of millions of nucleotides that can be assembled into one or more contiguous sequences. Each of these instances critically depends on correct identification of individual nucleotides, one at a time, at different positions along a template nucleic acid strand.
The human genome project was accomplished entirely by using conventional fluorescent Sanger dideoxyribonucleotide sequencing techniques. Since that time, follow-on technologies have simplified the procedure for obtaining polynucleotide sequence information with the intention of integrating genomic analysis into routine clinical and industrial laboratory applications.
Alternative nucleic acid sequencing platforms include sequencing by hybridization, and sequencing-by-synthesis. In the first instance, detectably labeled strands of DNA are contacted under hybridizing conditions with an array of up to many thousands of defined probe sequences immobilized to a solid support. Short duplexes formed in the procedure can be detected and analyzed by a computer for assembly into a contiguous sequence. Sequencing-by-synthesis procedures have taken various forms and also have been successful. Automation and improvements in the chemistry of labeled nucleotide addition, detection, and subsequent chemical processing have revolutionized procedures for acquisition of raw sequence information. In some cases, only relatively short stretches of nucleic acid sequence are determined, but massively parallel processing provides the information needed to deduce nucleic acid sequence on the scale of a genome.
Generally speaking, there is a need for extended sequencing read-length with improved base-calling accuracy across different sequencing platforms. The present invention addresses this need.

Nucleic acid sequencing method and system employing enhanced detection of nucleotide-specific ternary complex formation


A honeycomb body, which is composed in such a manner that a strip of corrugated foil made of heat-resistant stainless steel containing aluminum and a strip of flat foil made of stainless steel are alternately wound or laminated on each other, is incorporated into an outer cylinder made of metal and integrated into one body by means of diffusion bonding, so that a diffusion bonded metallic catalyst carrier can be formed. Surface roughness of the strip of foil after the completion of diffusion bonding is 0.001 to 2.0 μm when it is expressed by center line average height Ra, and no sintered bridges are formed at both end portions of the diffusion bonded section in the longitudinal direction. The catalyst carrier is manufactured in a condition so that λb, which is defined byλb=6.8×10−12×δf−1×F1/2×Ra−1/2×T1/4×exp(15000/T)×b1/2,can be in a range from 8 to 20 where thickness of the strip of foil is δf (m), average roughness of the foil surface is Ra (m), back tension in the case of winding is F (kgf), contact width of the piece of flat foil with the piece of corrugated foil is b (m), heat treatment temperature is T (K), and degree of vacuum is Pout (Pa), under the condition that 7.52×109×exp(−35000/T)≧8×Pout.

Ceramic carrier have been conventionally used for catalytic converters used for purifying exhaust gas discharged from automobile engines. However, recently, the use of metallic catalyst carrier is increasing because the resistance to heat of the catalyst carrier is high and, further, the pressure loss caused by the catalyst carrier is low and furthermore catalytic converters into which the catalyst carrier are incorporated can be easily mounted on automobiles.
As shown in FIG. 1, a conventional catalyst carrier 1 is manufactured in such a manner that a metallic honeycomb body 2 composed of heat-resistant stainless steel foil containing aluminum is incorporated into an outer cylinder 3 made of metal. As shown in FIG. 2, the metallic honeycomb body 2 is manufactured in such a manner that a piece of strip-like flat foil 5, the thickness of which is approximately 50 μm, and a piece of strip-like corrugated foil 6, which is made by corrugating a piece of strip-like flat foil 5, are put on each other and spirally wound round a winding shaft 8 in the direction of arrow B. On the piece of strip-like corrugated foil 6, a ridge 7 is formed at each wave in the width direction. In the columnar metallic honeycomb body 2 in which the piece of corrugated foil is spirally wound, a large number of vent holes 4 are formed in the axial direction of the columnar body. Catalyst carried is supported in these vent holes 4. In this way, the catalytic converter is composed.
High durability is required of the catalytic converter because it must stand the severe heat cycle given off by the exhaust gas at a high temperature discharged from an engine and further it must stand the intense vibration from the engine. Therefore, in the conventional catalyst carrier 1, the flat foil 5 and the corrugated foil 6 of the metallic honeycomb body 2 are joined to each other at the contact section, and further an outer circumference of the metallic honeycomb body 2 and an inner circumference of the outer cylinder 3 are joined to each other.
Concerning the joining means, there are provided various means such as soldering, diffusion bonding, resistance welding, laser welding and so forth. Diffusion bonding is advantageous because no solder is required and further no specific welding jig is required and, furthermore, diffusion bonding can be appropriately used for mass production.
In general, when diffusion bonding is conducted, members to be joined to each other are made to come close to each other and are heated to high temperature in a high vacuum. In diffusion bonding of the metallic honeycomb body 2 in which pieces of foil are spirally wound, it is impossible to apply surface pressure to the metallic honeycomb body 2 from the outside. Therefore, when back tension is given to the flat foil 5 in the direction of arrow A in the process of winding as shown in FIG. 2, surface pressure can be given, so that the flat foil 5 and the corrugated foil 6 can be made to come close to each other. When the thus formed metallic honeycomb body 2 is heated to high temperature in a high vacuum, the flat foil 5 and the corrugated foil 6 are subjected to diffusion bonding, so that the catalyst carrier 1 can be obtained.
FIG. 3 is a diagram showing temperature curves of the pressures of saturated vapors of iron, chromium and aluminum composing this stainless steel. The pressure of saturated vapor is defined as a value at which the pressure of vapor of a liquid (solid) becomes constant in a vapor phase space when the vapor phase and the liquid phase (solid phase) of the same substance coexist in an equilibrium state. The value of the pressure of a saturated vapor is different for each substance. This value is increased when the temperature is raised. Therefore, when a temperature curve of pressure of saturated vapor is located in an upper portion on the diagram, vaporization tends to occur. Accordingly, aluminum is most vaporized in the materials composing this stainless steel. Due to the foregoing, when the metallic honeycomb body 2 is heated to high temperature in a high vacuum, aluminum is mainly vaporized from stainless steel foil containing aluminum. For the above reasons, when the metallic honeycomb body 2 is heated to high temperature in a high vacuum so as to conduct diffusion bonding on the metallic honeycomb body 2, aluminum is vaporized from the metallic honeycomb body 2, and resistance to oxidation is deteriorated.
However, as shown in FIG. 3, a section of diffusion bonding is not formed in a temperature range of not higher than 1400 K, and a section of diffusion bonding is formed in a temperature range of not lower than 1400 K. This shows that it is necessary for aluminum, the quantity of which is not lower than a predetermined value, to be vaporized in order to form a section of diffusion bonding.
Due to the foregoing, the following are required in order to obtain a metallic honeycomb body of high quality.
(1) Aluminum, the quantity of which is not less than a predetermined value for obtaining a section of diffusion bonding, is vaporized.
(2) Vaporization of aluminum is suppressed to a value not more than a predetermined value so that resistance to oxidation is impaired, that is, it is necessary to control vaporization of aluminum in the process of diffusion bonding.
As a method of controlling vaporization of aluminum in the process of diffusion bonding of the metallic honeycomb body 2, Japanese Unexamined Patent Publication No. 9-215930 discloses the following means. According to the above method, the metallic honeycomb body 2 is covered with a cover having holes and subjected to diffusion bonding. Due to the foregoing, residual oxygen is discharged outside from the holes, and generated aluminum vapor is made to stay close to the metallic honeycomb body 2. According to the above proposal, vaporization of aluminum can be surely suppressed, however, it is necessary to attach the covers to all honeycomb bodies 2, which remarkably deteriorates the productivity. According to this proposal, heat treatment of diffusion bonding is conducted at 1300° C. in a vacuum. When heat treatment is conducted at such a high temperature in a vacuum, aluminum is intensely vaporized, and diffusion bonding cannot be sufficiently done. Therefore, in order to ensure resistance to heat, it is necessary to provide another means instead of the cover described above.
In the same manner, Japanese Unexamined Patent Publication No. 5-168945 discloses another means for controlling vaporization of aluminum in the process of diffusion bonding of the metallic honeycomb body 2. According to this method, a cover is set on the metallic honeycomb body 2, and a clearance is provided between the cover and the outer cylinder. Under the above condition, diffusion bonding is conducted. Due to the foregoing, residual oxygen is discharged outside from the clearance, so that generated aluminum vapor is made to stay close to the metallic honeycomb body 2. According to the above proposal, vaporization of aluminum can be surely suppressed, however, it is necessary to attach the covers to all honeycomb bodies 2, which remarkably deteriorates the productivity.
The applicant filed a patent, by Japanese Unexamined Patent Publication No. 8-38912, in which the following method is proposed. The average roughness (Ra) of a surface of the flat foil and that of a surface of the corrugated foil before diffusion bonding are kept to be not less than 0.001 μm and not more than 0.2 μm, and further the contact width of the flat foil with the corrugated foil is kept to be not less than 30 μm. Due to the foregoing, diffusion bonding can be excellently conducted in all regions of the honeycomb body from the center to the outer circumferential section by giving a back tension, the intensity of which is not higher than a value at which buckling is caused in the vent hole of the honeycomb body, and also by reducing the diameter of the outer cylinder. Also, the applicant filed Japanese Unexamined Patent Publication No. 10-309472 in which the following method is proposed. The contact width of the flat foil with the corrugated foil is kept at a value not less than 5 times of the thickness t of the flat foil and the corrugated foil. The flat foil and the corrugated foil are wound while a back tension, the intensity of which is 0.2 to 1.5 kgf/cm, is being given to the honeycomb body, and diffusion bonding is conducted in a temperature range from 1100 to 1250° C., and it is preferable that diffusion bonding is conducted in a temperature range of vacuum heat treatment corresponding to the average roughness Rac (μm) in the width direction of the plane foil.

This patent is subject to a terminal disclaimer.

Diffusion bonded metallic catalyst carrier and production thereof


A compact, high-efficiency, high-power, solid state light source, comprising a high-power solid state light-emitting device, a light guide having a proximal light-receiving end proximate the light-emitting device and a distal light-transmitting end spaced farther from the light-emitting device, and a mechanical light guide fixing device coupled to the light guide near its proximal end, to hold the proximal end of the light guide in position near the light-emitting device.

Light sources for endoscopic use are generally of two types: incandescent filament lamps and arc lamps. Incandescent lamps produce light by passing current through a tungsten filament, causing it to radiate light in proportion to its blackbody color temperature. The hotter the filament, the higher its color temperature and the more nearly it approaches daylight with a color temperature of approximately 5500K. Tungsten filament lamps range in color temperature from approximately 2400–3400K. Because of the low color temperature, objects illuminated by a tungsten filament light source appear slightly yellow due to the low output of blue light from these sources. Arc lamps produce light by creating a plasma between two electrodes within the sealed bulb. White light from these lamps can be produced by choosing the appropriate fill gas (usually Xe) and pressure (usually several atmospheres). Color temperature of common arc lamps is approximately 4000–6000K. Both types of lamps, filament and arc, are very inefficient in converting electrical power to light, and consequently produce large amounts of heat. The heat must be dissipated. It also contributes to a shortened useful life of such light sources.
There have been numerous attempts to utilize low power (<1 W electrical power consumption, typically operating below 100 mW) LEDs coupled to fiber optic light guides as light sources for endoscopy, dentistry, and for remote illumination of objects (as with a flashlight). Most of these prior attempts employ numerous low power LEDs for remote illumination. Multiple LEDs are necessary because the light output from a single, low power LED is very low and there is poor coupling of light emitted by the LED(s) into the optical fiber. An example of several coupling methods appears in U.S. Pat. No. 6,331,156 whereby the inventors place the fiber optic directly in front of either a surface mount or cylindrical LED without the use of additional optical components, coatings or gel. This patent also exemplifies the use of additional optical components in the form of lenses or mirrors in order to collect light generated from a standard, unmodified LED package configuration. US published patent application 2004/0004846 A1 utilizes a lens to couple the light emitted by an LED into a fiber optic. US published patent application 2003/0156430 A1 describes a device that consists of a number of individual LEDs mounted on mirrors, the arrangement of the LEDs and mirrors having a common focal point at the input end of the fiber light guide. U.S. Pat. No. 6,260,994 describes a plurality of LEDs mounted between a spherical or parabolic reflector and a lens, which directs the light emitted by the LEDs into the light guide fiber. In this invention, the LEDs emit light towards the collecting lens and away from the reflector. In U.S. Pat. No. 6,318,887, the LEDs are positioned so as to emit radiation towards a reflector, which then reflects light through a transparent printed circuit board and towards a lens and fiber light guide. In US published patent application 2002/0120181 A1, light emitted by several LEDs is collected along a common optical axis through a series of beam splitting prisms, in at least one embodiment with the use of lenses to couple the light from the LED into the prism, and then into the fiber. In these examples, the LED packages are not modified; multiple, low power LEDs are employed in order to attain a reasonable level of illumination; and in most of these examples, external optical components are employed in order to increase the coupling efficiency between the LEDs and the light guide fiber.
In US published patent application 2003/0231843, numerous low power LEDs are coupled into individual fibers, which are combined together at the distal end of the device to produce intense light for curing dental epoxy. This patent application describes an approach in which the LED package and light guide fiber are modified in order to increase the optical coupling efficiency between the two. In one embodiment, the cladding material from the fiber is removed and the fiber core is placed within the LED epoxy lens. The exterior of the epoxy lens is coated with a low refractive index "clad" that produces total internal reflection of the light emitted by the LED. Some of the light reflected by this LED clad can make its way into the core of the fiber and be transmitted to the distal end of the device. This patent application also includes a description of a taper attached to the external surface of the LED dome lens that couples the light into the fiber. Again, however, additional optical elements (cladding or tapers applied to the LED) are used. Also, the device employs numerous low power LEDs to attain sufficient light output from the device. This type of arrangement would be difficult if not impossible to implement with a high power LED because of the high operating temperature of these LEDs (up to 135 degrees C.). At high temperatures, the epoxy used in typical LED packages will melt or crack due to thermal cycling. In addition, high temperatures will cause the epoxy to discolor, typically becoming yellow. This will impart a yellow cast to the light, thereby lowering its effective color temperature and its desirability as a visual light source. In addition, discoloration will absorb lower wavelengths of light emitted by the LED, particularly those wavelengths in the blue and UV region of the spectrum that are essential for epoxy curing and fluorescence applications.

Compact, high-efficiency, high-power solid state light source using a single solid state light-emitting device


A dual drive gear of an actuation assembly for a transfer case includes an annular disk, a dual drive gear hub, and a sense plate. The annular disk has an inner periphery and an outer periphery. The outer periphery defines a plurality of teeth projecting radially outward. The dual drive gear hub is attached to the inner periphery of the annular disk and has an inner surface that defines a bore extending through a center of the dual drive gear. The dual drive gear hub includes a pair of curved walls projecting from a first axial end face of the annular disk. The sense plate projects from a second axial end face of the annular disk opposite of the first axial end face and includes a plurality of curved wall sections. The annular disk, the dual drive gear hub, and the sense plate are formed together as a single piece.

The background description provided here is for the purpose of generally presenting the context of the disclosure. Work of the presently named inventors, to the extent it is described in this background section, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted as prior art against the present disclosure.
A transfer case transfers power from a transmission of a vehicle to front and rear axles of a vehicle via drive shafts. A transfer case typically operates in multiple modes, such as two wheel drive (2 WD) and four-wheel drive (4 WD), and multiple ranges, such as low, high, and neutral. Vehicles with a manual transfer case typically include a selector lever that is mechanically coupled to the transfer cases to enable a driver to manually shift the transfer case between modes and ranges. Vehicles with an EMOD transfer case typically include a switch or button that enables a driver to control an electric motor to automatically shift the transfer case between modes and ranges.
An EMOD transfer case typically includes an input shaft, a first output shaft, a second output shaft, a planetary gear set, a range shift mechanism, a mode clutch, a clutch actuator, a dual drive gear assembly, and an electric shift motor. When the transfer case is in high, the range shift mechanism connects the first output shaft directly to the input shaft. When the transfer case is in low, the range shift mechanism connects the first output shaft to the input shaft through the planetary gear set. When the transfer case is in 4 WD, the mode clutch couples the second output shaft to the first output shaft. When the transfer case is in 2 WD, the mode clutch decouples the second output shaft from the first output shaft.
The shift motor rotates the dual drive gear assembly via a reduction gear set to actuate the range shift mechanism and the mode clutch. The clutch actuator converts the rotational force of the dual drive gear assembly into an axial force that applies the mode clutch or releases the mode clutch. The range shift mechanism converts the rotational force of the dual drive gear assembly into an axial force that axially translates a reduction hub splined to the first output shaft. When the transfer case is shifted to high, the reduction hub is translated to a first axial position in which external splines on the reduction hub engage internal splines on the input shaft. When the transfer case is shifted to low, the reduction hub is translated to a second axial position in which the external splines on the reduction hub engage internal splines on a carrier gear of the planetary gear set. When the transfer case is shifted to neutral the reduction hub is translated to a third axial position between the first and second axial positions. In the third axial position, the external splines on the reduction hub do not engage the internal splines on the input shaft or the internal splines on the carrier gear.

Electro-mechanical on demand (EMOD) transfer case—dual drive gear and shift fork consolidation


A conductor retention member for a stator core includes a body formed from a non-electrically conductive material. The body includes a radial outwardly facing edge and a radial inwardly facing edge. A plurality of openings extends between the radial inwardly facing edge and the radial outwardly facing edge formed in the body. The body is configured and disposed to be arranged at an axial end of the stator core with the plurality of openings registering with corresponding ones of a plurality of stator slots.

Exemplary embodiments pertain to the art of electric machines and, more particularly, to a conductor retention member for a stator assembly.
Many electric machines include a moveable element that rotates relative to a stationary element. The stationary element, referred to in some cases as a stator having a stator core that supports one or more conductors. The stator core may be formed by stacking and joining a number of laminations. The stator core may include a plurality of stator teeth that are spaced one from another by voids or stator slots. The stator slots receive the one or more conductors. In some cases the stator slots are open, in other cases the stator slots may be semi-closed. Semi-closed stator slots include projecting portions or teeth that support the one or more conductors to the stator core. Semi-closed stator slots are typically limited to axial insertion of the one or more conductors. Open stator slots may be filled by axial or radial insertion of the one or more conductors.
After loading with the one or more conductors, open stator slots are often subjected to a staking process. The staking process deforms a radially inward end of each of the teeth to partially close each of the stator slots and support the one or more conductors. Alternatively, slot wedges may be inserted into each of the stator slots to support the one or more conductors. Supporting the one or more conductors through semi-closed stator slots, staking, or stator wedges limits potential interference with the moveable element or rotor.

Conductor retention member for a stator assembly


An ink jet recording apparatus includes a recording head having a discharge port for discharging ink, a liquid chamber communicating with the discharge port, a supply port provided in the liquid chamber for supplying ink to the liquid chamber, a communication port provided in the liquid chamber, and an air chamber communicating with the liquid chamber through the communication port to define a closed space in communication only with the liquid chamber. The cross-sectional area of the communication port is smaller than both the cross-sectional area of the air chamber and the area of the wall of the liquid chamber on which the communication port is located.

1. Field of the Invention
This invention relates to a recording head and an ink jet recording apparatus having the recording head wherein ink is discharged to form droplets of the ink and the droplets are caused to adhere to a recording medium such as paper to thereby accomplish recording.
2. Related Background Art
The ink jet recording method is a recording method whereby ink (recording liquid) is discharged from an opening provided in a recording head and is caused to adhere to a recording medium such as paper to thereby accomplish recording, and has the numerous advantages that very little noise is produced, that high-speed recording is possible, that plain paper can be used and that recording paper of special construction is not required. Ink jet recording heads and ink jet recording apparatus of various types have heretofore been devised. As shown in FIG. 1 of the accompanying drawings, an ink jet recording apparatus according to the prior art is provided with a restoring system as shown in FIG. 2 for the purposes of filling a liquid chamber with ink during the interchange of a head and preventing unsatisfactory discharge or non-discharge, or recovering the apparatus from unsatisfactory discharge. That is, when the head 52 is to be filled up with ink during the interchange of the head, a cap 51 may be brought into intimate contact with a front face plate 56 in FIG. 1, negative pressure may be generated in the cap 51 by negative pressure generating means or a suction pump 57, and ink may be poured into the head through a supply tube 58 communicated with an unshown ink tank, a liquid chamber 53 and liquid paths 54 in the named order and discharged from an orifice 55.
Now, the means of multiplying the discharge port 55 is adopted to improve the recording speed of the ink jet recording apparatus, but, for example, if an attempt is made to fill such a head with ink by the above-described method, the ink will flow out from the discharge port communicated with the liquid path in the lower portion before the ink completely fills up the interior of the liquid chamber. Because the liquid path row and the liquid chamber are long, a bubble 59 will sometimes remain in the liquid chamber 53 as shown in FIGS. 2 and 3 of the accompanying drawings. Such a bubble 59 cannot completely be removed even if the performance of the pump when supplying the ink to liquid chamber 3 by the pump is improved. In some cases, the adherence of the bubble 59 to the rear end of the liquid paths 54 (which is adjacent to the liquid chamber 53) has caused non-discharge and mal-discharge of the ink.
U.S. Pat. No. 4,158,847 discloses a printer head having air bubbles in an ink distributor device. However, this configuration also fails to resolve the above-stated drawbacks. Besides, in some occasions, owing to the vibration of the device, air bubbles in the ink distributor device would enter the ink passage. Thus the ink discharge is deteriorated.

Ink jet recording apparatus and recording head having an air chamber defining a closed space in communication with a liquid chamber


A method of utilizing a filter having a filter body removing solid particles from a fluid, in order to extend the life cycle of the filter body before cleaning or replacement thereof is required, characterized in applying to the fluid, upstream of the filter body, an AC electrical field of a frequency and intensity to agglomerate solid particles in the fluid reaching the filter body, such as to reduce the number of smaller particles in the fluid tending to clog the filter body. Also described are a plurality of filter constructions for extending the life cycle of the filter body in accordance with the above method.

The present invention relates to filters, and particularly to a method, filter and pre-filter for extending the life cycle of the filter body before cleaning or replacement is required. The invention is particularly useful with respect to filters of fibrous material, such as paper, for removing solid particles from air or other gases, and the invention is therefore described below with respect to such applications.
The term "air filter" as used herein is intended to include filters not only for air, but also for other gases; the term "paper filter" as used herein is intended to include not only folded paper filters but also other kinds of fiber filters; and the term "solid particles" as used herein is intended to include not only dust, but also other micro-bodies such as aerosols.
One of the largest applications for air filters at the present time is for cleaning the air supplied to internal combustion engines and air compressors. Another popular application is for clean rooms wherein High Efficiency Particle Arrestance (HEPA) filters are mostly used. The most common type of air filters is the paper filter, made up of multiple layers of folded paper or other fiber.
A method for cleaning paper filters by air jets directed through the filter in a direction opposed to the normal airflow path was disclosed in Copley U.S. Pat. No. 4,364,751 and Gillingham et al. U.S. Pat. No. 4,504,293. Both used a pulse jetting formed by a system of valves and nozzles. Since dust particles are retained by the fiber mesh quite tightly, the pulse jet cleaning method can not provide sufficient recovery of the filter, and after only a limited number of cleaning cycles at most, the filter must be discarded and replaced with a new one.
U.S. Pat. Nos. 5,797,978 and 6,391,097 disclose a novel air filtration technology based on plastic discs secured in a tight stack. The discs faces are made with a pattern forming small filtering passageways. An electrode metallic layer is embedded in the plastics and is connected to a DC voltage source in order to generate an electrostatic field between the discs. This field acts on the dust particles to divert them from the air stream and to settle them on the faces of the plastic discs. Such a disc structure can sustain pressure load higher than the fiber material and accordingly enables easy cleaning by reverse air impulses. A novel filter system that includes an air impulse generator for cleaning the filter many times is described in U.S. Pat. No. 6,641,646.
However, paper filters are generally disposable; that is when clogged they generally must be discarded and replaced with new ones. Cleaning paper filters by airflow in the opposite direction is generally not so effective when done by air jets and might cause rupture of the filter if exposed to a blast of air impulse. Periodical replacement of disposable air filters is costly and constitutes an ecological burden.

Method and construction of filters and pre-filters for extending the life cycle of the filter bodies therein