A voltage switch circuit includes four transistors. The four transistors may be transistors used to build logic gates. The operation of the voltage switch circuit may include precharging the output terminal of the voltage switch circuit, conditioning of the voltage switch circuit and boosting the voltage of the output terminal.

1. Field of the Invention
The present invention relates to a memory, and more specifically, to a memory having a voltage switch circuit with one bias voltage changed in each state of conditioning.
2. Description of the Prior Art
Memory devices are electronic devices arranged to store electrical signals. The non-volatile memory does not lose its data when the system or device is turned off and may be implemented as a MOS transistor that has a source, a drain, an access or a control gate, and a floating gate. It is structurally the same as standard MOSFET except its gate is floating, which is electrically isolated. There are many structural variations of MOS devices to enhance the operation or reduce the size of non-volatile memory devices.
Considerations including purpose of the device, power consumption, size, retention capacity and duration may influence design of non-volatile memory devices. For example, some non-volatile memory devices may be categorized as floating gate or charge-trapping from a programming perspective.
Non-volatile memory devices may be implemented as non-volatile memory arrays that include a plurality of non-volatile memory cells arranged in rows and columns. In general, 1T non-volatile memory cells operate as follows. During an erase operation, electrons are removed from a floating gate of the non-volatile memory cell, thereby lowering the threshold voltage of the non-volatile memory cell. During a program operation, electrons are injected into the floating gate of the non-volatile memory cell, thereby raising the threshold voltage of the non-volatile memory cell. Thus, during program and erase operations, the threshold voltages of selected non-volatile memory cells are changed. During a read operation, read voltages are applied to selected non-volatile memory cells. In response, read currents flow through these selected non-volatile memory cells.
Certain types of nonvolatile memory devices, circuits employing floating-gate devices, high-voltage drivers and other circuits fabricated in logic CMOS require relatively high voltages (e.g., 10 volts in a 3.3 volt CMOS process). In all these circuits, switches are required to selectively apply the high voltages to specific circuit elements.
Tolerating a high-voltage supply, generating intermediate voltages, as well as generating high-voltage drive signals from logic low-voltage signals while minimizing power consumption, are substantial design parameters for switch circuits adapted to program memory devices.

Memory having a voltage switch circuit with one bias voltage changed in each state of conditioning


A method of producing a tire having an outside-in ply construction is provided. The method includes the steps of: providing a tire building drum; laying an inner liner on said drum, applying a first layer of ply on the right hand side of the drum so that a first end of the first ply layer is located over a first bead area while the second end of the first ply layer extends laterally outwards therefrom, applying a first bead over the first bead area and ply end; applying a second layer of ply on the left hand side of the drum so that one end of the second ply layer is located over a second bead area, while the second end extends laterally outwards therefrom; applying a second bead over the second toeguard and end of second ply layer; folding the second end of the first layer of ply over the first bead until the second end of the first layer of ply contacts the second bead; folding the second layer of ply over the second bead and apex so that the outer end of the second layer of ply is located over the first bead; and shaping the carcass into a toroid. A second method of building a tire carcass comprising the steps outlined above, with an additional third layer of ply being added that has lateral ends extending from said first bead to said second bead. The tire carcass may additionally comprise one or more pairs of sidewall inserts.

Modern passenger tires are typically constructed as shown in FIGS. 1 and 2, wherein the turn-up ends 20 of the ply wrap around the bead cores 26 in an inside-out fashion with reference to the interior 30 and exterior 32 of the tire. When the tire is inflated, the radial ply 15 exerts an inherent upward force F1 as shown in FIG. 1. The force F1 exerted by the radial ply 15 causes the bead cores 26 to rotate in a direction R1, causing the toe 36 to lift away from the rim (not shown). This configuration is standard on the vast majority of tire constructions.
It is known in the prior art to utilize an "outside-in" configuration wherein the ply is wrapped around the bead so that the turn up end is located on the inside of the tire or inside the apex. The reversing of the location of the ply turnup results in the reversing of the direction of the force on the ply (not shown), torquing the toe 36 into the rim. Further, this reversed torquing action utilizes the material in the bead more efficiently allowing the bead size to be proportionately reduced. Other associated components can then also be reduced. Even a small decrease in the amount of materials needed to produce a tire can result in significantly decreased material expenses for a manufacturer engaged in high-volume tire production. There is a need for a tire having reduced weight that provides the desired performance characteristics and can be produced with fewer materials at a lower cost.

Method of manufacturing tire with turned down ply construction


A frame that holds a screen suitable for screen printing is manufactured using curable liquid resin. The liquid resin is received within a channel in a mold such that the resin contacts a screen positioned proximate to the channel. The liquid resin is then cured to a solid state to both secure the screen to the resin and form the frame holding the screen. Agents for curing the liquid resin may include, but are not limited to, light (such as ultraviolet light or visible light), an electron beam, and chemical curing agents. A substrate may be pressed against the screen opposite the mold to hold the screen against the mold. Furthermore, an inorganic material may be mixed with the curable liquid resin to provide a matrix that reinforces and strengthens of the screen printing frame when the resin is cured to a solid state.

Screen printing, also known as silk screen printing, has been around for hundreds of years. It is used to place an image or deposit material on a substrate in a desired pattern or shape. Screen printing machines use a tensioned screen of fabric or mesh mounted on a supporting frame. Printing an image typically involves spreading a photosensitive film on the tensioned screen and creating a "mask" or "resist" on all the areas of the screen that are to prevent the flow of ink, dyes or other fluid media onto the substrate being printed. A squeegee then forces ink, dyes, or other fluid media through the open areas of the screen onto the substrate to form an image on the substrate.
A screen printing frame and mesh system typically consists of a rigid frame made of wood, metal, or plastic. As will be discussed below, once the frame is constructed, a fabric or mesh screen is then stretched by hand or by mechanical means over the frame, and adhered to the frame using adhesives, staples, tacks, rope pounded into grooves in the frame, or through channels and locks to the frame to secure the tensioned screen to the frame. Such frames are often referred to as "stretch and glue" frames. Screen printing frames have also been produced in which a screen is first fastened to a frame, and by rolling, telescoping, or expanding the sides of the frame, the fabric is stretched over the frame. Locking mechanisms are then used to secure the frame and screen at the desired tension.
A screen printing frame provides both a stable platform for holding a stretched screen, and a device that can be held in place during the printing process. Traditionally, there are three basic steps to create a screen frame that is ready for imaging. The first is to manufacture the frame itself. The second is to attach the screen material to the frame at a desired tension. The third is to place the emulsion or "mask" onto the screen in preparation for an image to be created on it. In the prior art, these three tasks are all separate and distinct from each other, and traditionally take place in different locations.
In the case of wooden frames, for example, to manufacture the frame requires cutting the wood to size, with four corner miters, joints, or corner connectors that are stapled, inserted, or glued to create a finished frame ready for attaching the screen. In the case of metal frames, the metal needs to be cut to the desired size, and welded, bonded, finish ground, and connected at the corners to form the finished frame. In the case of plastic frames, a heavy duty metal or high strength plastic closed mold must be made to withstand the strong injection force necessary to inject molten plastic into the mold cavity and thereby obtain the desired frame shape. These molds are very expensive to create, requiring many hours of machining in addition to the raw cost of the mold material itself. Regardless of material of construction, the frames are taken from their place of manufacture and moved to the next stage in the process, either within the facility in the case of a frame manufacturer that provides pre-stretched frames, or to a frame distributor to stretch and apply the screen for a customer. Frames may also be taken directly to the final customer who desires to stretch and apply the screen for themselves.
The process of manufacturing a frame transporting the frame as needed, and attaching a screen to the frame requires substantial handling, is burdensome, and can be expensive. What is needed is a method and system for manufacturing a screen printing frame in which the frame is manufactured and the screen adhered to the frame at the same time, thus requiring less handling and producing a screen printing frame at a much lower cost. The present invention is directed to addressing this need and other shortcomings that exist in the prior art.

Method and system for manufacturing a screen printing frame holding a screen using curable resin


The CMOS LTPS TFT substrate manufacturing method, by a semi-transparent mask, forms a second photoresist pattern having a second photoresist section above a second poly-Si active layer where P-type ion heavy doping is to be performed as protection. Then, N-type ions are effectively prevented from being implanted into the second poly-Si active layer's second source/drain contact region when conducting N-type ion heaving doping to the first poly-Si active layer. There is no need to compensate P-type ions during the subsequent P-type ion heavy doping to the second poly-Si active layer for forming the second source/drain contact region. The present invention therefore reduces the productivity loss in the P-type ion heaving doping process and, as N-type ion heaving doping does not affect the PMOS transistors, enhances the electrical convergence of the PMOS transistors. Damage to the film lattice structure by the ion implantation is also reduced, thereby increasing the device reliability.

In the field of display technologies, liquid crystal display (LCD) and active matrix organic light emitting diode (AMOLED) are widely applied to mobile phones, personal digital assistants (PDAs), digital cameras, computer screens, and notebook screens, due to their thin thickness, high quality, power saving, and low radiation.
Thin film transistor (TFT) array substrate is a key component to LCD and AMOLED devices, directly affecting the performance of these flat panel display devices. For the provision of driving circuit to the display devices, the TFT array substrate is usually configured with multiple gate scan lines and multiple data lines, jointly defining multiple pixel units. Each pixel unit is configured with TFT and pixel electrode. The gate of the TFT is connected to a corresponding gate scan line. When the voltage on the gate scan line reaches the threshold voltage, the source and drain of the TFT are conducted, and the voltage on the data line reaches the pixel electrode, thereby controlling the display of the corresponding pixel unit. Usually the TFT on the array substrate includes gate electrode, gate insulation layer, active layer, source and drain electrodes, and insulating protection layer, stacked sequentially from bottom to top on the substrate.
Compared to traditional amorphous silicon (a-Si) TFT, low temperature poly-silicon (LTPS) TFT,
due to better carrier mobility, is widely applied to small- to medium-sized, high-resolution, LCD and AMOLED display panels, despite its more complex manufacturing process. LTPS is considered as an important material to achieve low-cost and full-color flat panel displays.
Currently, a metal oxide semiconductor (MOS) device is usually formed using LTPS. A MOS device may be a negative channel MOS (NMOS) device, a positive channel MOS (PMOS), or a complementary MOS (CMOS). The difference between NMOS and PMOS transistors mainly lies in that their source/drain contact regions are respectively formed using N-type ion heavy doping (P+, 1×1014-1×1015 ions/cm2) and P-type ion heavy doping (B+, 1×1014-1×1015 ions/cm2), and NMOS and PMOS transistors jointly form CMOS transistor. Hot carrier effect is a major factor causing MOS devices to fail. As MOS devices are continuously reduced in size, they suffer even severer hot carrier effect. To effectively control the hot carrier effect for LTPS MOS devices so as to enhance their reliability and improve the leakage current under negative bias condition, existing LTPS NMOS adopts a lightly doped drain (LDD) method in the manufacturing process by providing a lightly doped region in the poly-silicon (poly-Si) ditch around the source and drain, and distributing some voltage to this lightly doped region. Currently mostly applied LDD techniques are mask LDD and re-etch LDD. The manufacturing of LTPS array substrate using mask LDD forms the source/drain contact region by conducting N-type ion heavy doping to poly-Si active layer through photoresist pattern, and then forms the LDD region by conducting N-type ion light doping to poly-Si active layer through gate electrode self-alignment technique. Compared to the above mask LDD technique, re-etch LDD technique forms the gate electrode through two etchings, instead of through photoresist pattern, after patterning the poly-Si active layer. The metallic pattern after the first etching defines the source/drain contact region to be heavily doped. Then the gate electrode is obtained after the second etching. The LDD region is formed by conducting N-type ion light doping to poly-Si active layer through gate electrode self-alignment technique. Compared to mask LDD technique, the main advantage for re-etch LDD technique is a lithographic process is omitted, thereby saving the production cost for a mask, reducing the time for manufacturing LTPS TFT substrate, and increasing productivity. In manufacturing CMOS LTPS TFT substrate, usually 11˜14 masks are required. To reduce lithographic process, LTPS CMOS array technique often adopts re-etch LDD to replace mask LDD, which generally includes the following steps.
Step S10, as shown in FIG. 1, forms a buffer layer 200 on a substrate 100, a first poly-Si active layer 310 corresponding to NMOS and a second poly-Si active layer 320 corresponding to PMOS on the buffer layer 200, a gate insulation layer 400 on the buffer layer 200 covering the first and second poly-Si active layers 310 and 320, a metallic layer 500 deposited on the gate insulation layer 400, and a first photoresist pattern 910 above a middle section of the first poly-Si active layer 310 and a second photoresist pattern 920 above a middle section of the second poly-Si active layer 320 on the metallic layer 500 by coating photoresist on the metallic layer 500 and conducting exposure and development to the photoresist with a mask.
Step S20, as shown in FIG. 2, forms a first quasi-gate electrode 510′ above the first poly-Si active layer 310 and a second quasi-gate electrode 520′ above the second poly-Si active layer 320 by conducting a first etching to the metallic layer 500 using the first and second photoresist patterns 910 and 920 as shielding layer.
Step S30, as shown in FIG. 3, obtains a first source/drain contact region 3101 at lateral end sections of the first poly-Si active layer 310 by conducting N-type ion heavy doping (P+, 1×1014-1×1015 ions/cm2) to lateral end sections of the first poly-Si active layer 310 not covered by the first quasi-gate electrode 510′ using the first quasi-gate electrode 510′ as shielding layer.
Step S40, as shown in FIG. 4, obtains a first gate electrode 510 from the first quasi-gate electrode 510′ and a second gate electrode 520 from the second quasi-gate electrode 520′ by conducting a second etching to the metallic layer 500 ad lifting the first and second photoresist patterns 910 and 920, where the width of the first and second quasi-gate electrodes 510′ and 520′ is reduced as their lateral ends are etched.
Step S50, as shown in FIG. 5, obtains a first ditch region 3102 in the middle section of the first poly-Si active layer 310 below the first gate electrode 510, and a first lightly doped drain (LDD) region 3103 between the first ditch region 3102 and the first source/drain contact region 3101 by conducting N-type ion light doping (P+, 1×1012-1×1013 ions/cm2) to lateral end sections of the first poly-Si active layer 310 not covered by the first gate electrode 510 using the first gate electrode 510 as shielding layer.
Step S60, as shown in FIG. 6, forms a photoresist protection layer 950 on the gate insulation layer 400 and the first gate electrode 510 that covers the first poly-Si active layer 310, obtains a second source/drain contact region 3201 at lateral end sections of the second poly-Si active layer 320 and a second ditch region 3202 in the middle section of the second poly-Si active layer 320 below the second gate electrode 520 by conducting P-type ion heavy doping (B+, 1×1014-1×1015 ions/cm2) to lateral end sections of the second poly-Si active layer 320 not covered by the second gate electrode 520 using the second gate electrode 520 as shielding layer.
In the above CMOS re-etch LDD technique, as a mask for N-type ion heavy doping is omitted, the N-type ion heavy doping conducted to the first poly-Si active layer 310 corresponding to NMOS would also happen to the second poly-Si active layer 320 corresponding to PMOS. Subsequently, to compensate the phosphorus (P) ions implanted into the second poly-Si active layer 320 and to turn the second poly-Si active layer 320 from N-type to P-type semiconductor, a higher dosage of boron (B) ions has to be implanted during the P-type ion heavy doping, which results in the following influence.
1. The higher dosage of P-type ion heavy doping would compromise productivity of the P-type ion heavy doping process.
2. Uneven N-type ion heavy doping and incompatible depth of ion implantation during P-type ion heavy doping causes inferior electrical convergence to PMOS transistors.
3. The source/drain contact region of PMOS transistor undergoes ion doping three times, causing significant damage to the lattice structure of the gate insulation layer 400 and poly-Si film, and reducing device reliability, negative bias stability, and breakdown voltage.

Manufacturing method for CMOS LTPS TFT substrate

WUHAN CHINA STAR OPTOELECTRONICS TECHNOLOGY CO., LTD.


A storage device receives and holds a storage medium that is subjected to first servo writing processing for writing servo information, a Gray code of which is offset, from an inner cylinder or an outer cylinder to a predetermined cylinder and, after the first servo writing processing, subjected to second servo writing processing for writing servo information from an opposite direction to the predetermined cylinder and in which Gray codes are written to be offset not to overlap in the first or second servo writing processing and the pieces of servo information having different mark patterns are written in the first servo writing processing and the second servo writing processing. The storage device acquires cylinder information and mark patterns from the servo information written in the held storage medium and controls a position of a head based on the acquired cylinder information and mark patterns.

1. Field of the Invention
The present invention relates to a storage device that reads servo information, which is written in an inserted and held storage medium, with a head and controls a position of the head using the read servo information and a servo information writing method.
2. Description of the Related Art
Conventionally, recording density of storage media such as a magnetic disk, a magneto-optical disk, and an optical disk has been remarkably improved. This makes it possible to realize a reduction in size of a storage device and an increase in a recording capacity. Convenience of the storage device is improving.
In such storage media with the improved recording density, to accurately position a head on a target track, servo information such as a track number and a servo pattern (a servo mark) for demodulating a relative position of the head with respect to a track center is written by a servo track writer (STW). The STW writes the servo information from one direction on an outer side or an inner side of a storage medium. A control device such as a magnetic disk device performs, using the servo information, automatic control of a head that reads data from and writes data in the storage medium (see Japanese Patent No. 2645182).
In the writing of the servo information by the STW, deterioration in a quality of servo written in the storage medium due to erase called a side fringe occurs. Problems such as a servo mark mistake and misdetection of a Gray code during reading of the servo information by the head occur. The side fringe is caused by magnetic field leakage (write spread) of a write head that writes the servo information in the storage medium. As shown in FIG. 11, the side fringe is closely related to a yaw angle and a feeding direction of the STW. Specifically, as shown in FIGS. 12A to 12C, when the write head writes the servo information in an outer direction, the influence of the side fringe is large on the outer side. When the write head writes the servo information in an inner direction, the influence of the side fringe is large on the inner side. Therefore, an erase section enlarges and the servo quality is substantially deteriorated. In recent years, amid a further increase in track per inch (TPI), deterioration in an error rate of the servo information and deterioration in a position quality of the head due to the deterioration in the servo quality are becoming innegligible. FIG. 11 is a diagram of a relation between the yaw angle and the feeding direction of the STW. FIGS. 12A to 12C are diagrams for explaining the erase portions in the feeding direction of the STW.
As a method of preventing the deterioration in an error rate, the deterioration in a position quality, and the like due to the deterioration in the servo quality, a bidirectional STW that writes, on the outer side, the servo information while feeding an STW head to the inner side and writes, on the inner side, the servo information while feeding the STW head to the outer side is used. When the bidirectional STW is used, a boundary between the servo information written from the outer side and the servo information written from the inner side is present. This boundary shifts in a time direction and a radial direction because of a change in an environment or the like in writing the servo information. The shift causes non-detection or misdetection of servo. To use a storage medium in which the servo information is written by using the bidirectional STW, it is necessary to accurately read out the servo information written in this boundary (a cylinder as the boundary: a boundary cylinder).
However, when the storage medium in which the servo information is written by the bidirectional STW of the conventional technology described above is used, the boundary of the servo information written from both the directions is separated into two boundaries by a change in an environment or the like in writing the servo information. In other words, a boundary cannot be formed in a Gray code as intended and a position of the head for reading out or writing data cannot be correctly controlled.

Storage device and servo information writing method


A device for adjusting the phase position of a cam shaft of an internal combustion engine and for supplying an assembly with a partial vacuum, said device comprising: a phase setter for adjusting the phase position of the cam shaft relative to a crankshaft of the internal combustion engine; a vacuum pump for the assembly; and an attachment housing for the vacuum pump, wherein the attachment housing is mounted on the internal combustion engine and forms a housing or at least a housing cover for the phase setter.

1. Technical Field
The invention relates to a device comprising a cam shaft phase setter and a vacuum pump for mounting on an internal combustion engine, and also to an internal combustion engine with the device mounted.
2. Description of the Related Art
In order to reduce brake pedal forces in motor vehicles, in particular passenger cars and light-duty commercial vehicles, the vehicles are equipped with pneumatic brake servos. In conventional passenger car spark-ignition engines, the partial vacuums required for brake servos are applied by the suction pipe partial vacuums acting behind the suction inlet system throttle valve. In diesel engines and also modern spark-ignition engines with fuel injection, the suction pipe partial vacuums which arise during operation are in many cases not sufficient for powering the brake servos, because the load control deviates from conventional spark-ignition engines. Such internal combustion engines therefore use a separate vacuum pump which is driven by the respective engine. These pumps are generally driven by a cam shaft of the engine and are usually flange-mounted to a facing side of the cylinder head.
In order to increase the output and torque, and to reduce the emissions and fuel consumption, modern passenger car engines are increasingly equipped with cam shaft phase setters which are charged with engine oil pressure and using which the phase angle of an inlet cam shaft or outlet cam shaft or both cam shafts can be adjusted relative to an engine crankshaft. Usually, separate functional units of cam shaft phase setters and vacuum pumps are arranged on the cam shaft. Due to the required seal and coupling between the functional units and the respective drive, and as applicable between each other, and also in view of the configuration of the oil feed and oil eduction, such arrangements incur a comparatively elaborate construction. A direct coupling between the vacuum pump and a cam shaft also restricts the torque level and the arrangement of the vacuum pump.
DE 102 60 546 A1 discloses arranging a vacuum pump and a cam shaft phase setter coaxially next to each other on the same rotational axis. A rotor of the phase setter is placed, secured against rotating, on the cam shaft to be adjusted. The stator is driven by the crankshaft. The rotor is connected, secured against rotating, to the vacuum pump via a coupling. The vacuum pump comprises a housing which is flange-mounted to a cylinder head of the internal combustion engine, and a drive shaft which protrudes through the cylinder head and is connected, secured against rotating, to the rotor of the phase setter by means of the coupling. The vacuum pump is supplied with lubricating oil through a central bore of its drive shaft through the cylinder head.

Cam shaft phase setter and vacuum pump for an internal combustion engine

Schwabische Huttenwerke Automotive GmbH & Co. KG


Parallel digital data are transmitted along with a specific synchronization pattern added thereto. Each synchronization pattern adder adds the synchronization pattern at an equal timing for each channel. Parallel data after the synchronization pattern addition, are converted in parallel-to-serial converters into serial data which are in turn converted in an optical transmitter into optical signal. On the receiving side, the optical signal is converted in an optical receiver into an electric signal, from which the parallel data are restored in serial-to-parallel converters to be inputted to synchronization pattern detectors. The synchronization pattern detectors compare their shift register data and synchronization pattern and hold their synchronization pattern detection signal to be "1" for one time slot if the number of non-accord bits is within one. In the next time slot, a controller recognizes synchronization pattern detection when and only when all the synchronization pattern detection signals are "1". In this way, reliable synchronization pattern detection can be made regardless of the occurrence of any transmission error in the synchronization pattern.

Field of the Invention
This invention relates to data transmission systems used between computers or like terminals, for inter-board connection, or for data interfaces in data transmission systems, switching systems, etc.
In many data links in which digital data packets are transmitted between computers or boards, a specific synchronization pattern called a "delimiter" is added to the leading end or to both the leading and trailing ends of each packet to realize packet synchronization. Particularly, where the packets are variable in length, reliable detection of the delimiter is necessary for the recognition of the leading and trailing packet ends.
As an application of an optical fiber communication to the data link of a such system, there are fiber channels as disclosed in, for instance, Fiber Channel Physical Layer (FC-PH) Rev. 2.1, ANSI X3T9.3/91-071, May 25, 1991). For parallel digital data transmission, the parallel data is often converted through time division multiplexing into a serial signal for transmission of the data on a reduced number of data lines. In such data transmission systems, it is necessary for the receiving side to realize frame synchronization for the serial-to-parallel conversion in order to ensure that the parallel data channels inputted on the transmitting side and those outputted on the receiving side are in accord with one another. To realize frame synchronization, a specific synchronization pattern is applied, which enables the receiving side to detect the frame phase.
In such a data link, a first problem is encountered when a transmission error occurs in the synchronization pattern itself which is added to data to be transmitted. In this case, it is unable to recognize the packet or frame phase, thus making all the data contained in the packet or frame ineffective. The problem arises frequently, because in an optical data link such as fiber channels, the transmission line is basically not error-free. In the case where the length of the packet or frame is fixed, it is possible to avoid the problem considerably by adopting the so-called "forward protection", i.e., causing a synchronization pattern detector operation like that of a flywheel (for instance, Kaneko, "PCM Communication Techniques", pp. 109-116, Sanpoh, 1976). Where the length of the packet or frame is variable, however, such a method cannot be adopted. On the contrary, there are cases where the same pattern as the synchronization pattern is present and can be erroneously judged to be the synchronization pattern. To avoid this, in the usual data link data is encoded such that the same pattern as the synchronization pattern will not be present in the resultant data. For example, in the case of the fiber channels mentioned above, transmission line codes called 8B10B codes are used, and only predetermined data characters are used for the data section. Since the delimiter has a pattern which is not contained in any data character, usually there is no possibility of mistaking data as the delimiter. Even in such a case, however, the occurrence of a transmission error in the data gives rise to the possibility of the appearance of the same pattern as the delimiter.
A second problem that arises in parallel data link is that of transmission time differences or skews among the individual channels. In a well-known method of absorbing skews, a FIFO (first-in first-out) buffer is provided on the receiving side of each channel, and data is read out from each FIFO under control of an equal phase clock. This method poses a problem that the hardware is increased.
Further, in the case of transmitting parallel data after parallel-to-serial conversion, there is a requirement for frame synchronization on the receiving side. For the restoration to the original parallel data it is necessary to discriminate each channel after the serial-to-parallel conversion and make a feedback control to the frame phase at the serial-to-parallel converter or effect channel interchange. In the former method, the control requires a certain period of time. During this time, no data can be transmitted. For instantaneously establishing the frame synchronization, therefore, the latter method has to be used. As methods of channel discrimination, there is one in which a unique synchronization pattern is used for each channel (a similar method being disclosed in Japanese Patent application Kokai Publication No. Hei 04-115734), and one in which channel identifiers are added to data. In the former method, a common structure cannot be adopted for a pattern detection circuit for each channel, thus leading to high cost. The latter method, on the other hand, has a problem of transmission efficiency reduction.

Data transmission system using specific pattern for synchronization


A microorganism cells-immobilizing granular carrier and its manufacturing system.. Said microorganism cells-immobilizing granular carrier, which has a specific gravity of 1.00 to 1.20, and which has a contact angle of 2.degree. to 30.degree. formed between the carrier surface and n-paraffin, and which has a surface suitable for the attachment of a microorganism, is obtained by dripping a liquid composition containing a hydrophilic photo-curable resin having (a) at least two ethylenically-unsaturated bonds in one molecule, (b) photopolymerization initiator, and (c) water-soluble macromolecular polysaccharide capable of gelatinizing through contact with alkaline metal ions or polyvalent metal ions, into an aqueous medium containing alkaline metal ions or polyvalent metal ions to gelatinize the composition; and irradiating the composition with ultraviolet radiation so as to harden said composition.

Immobilized microorganisms have been noticed in recent years because they may be used to realize efficient continuous fermentation in a bioreactor.
Many methods, including the entrapment method and physical adsorption method, have been known to date as microorganism immobilizing methods. Immobilization of a microorganism by the entrapment method, however, has a problem in that the cost greatly increases because it requires a complicated operation of wrapping a previously-cultured microorganism suspension in a macromolecular gel.
The physical adsorption method makes it possible to immobilize a microorganism merely by introducing a carrier into a microorganism suspension. Therefore, the method has an advantage in that the operation of entrapping a microorganism performed in the entrapment method is not necessary. Carriers such as activated carbon, porous glass, sellite, chitin, and cellulose are known as carriers used for the physical adsorption method.
However, because surface structures of these carriers are not suitable for attachment of microorganisms, there is a problem in that only a small number of microorganisms are attached, and there is a disadvantage in that it is difficult to cause a flow in a fermenter or bioreactor, depending on the type of carrier, because of its high specific gravity.
It is the first object of the present invention to provide a granular carrier for immobilizing microorganism cells, whose surface structure is suitable for attachment of a microorganism and whose specific gravity ranges between 1.00 and 1.20, and which does not lower the flowability in a fermenter or bioreactor.
Moreover, a device for manufacturing the above granular carrier is disclosed in, for example, the official gazette of Japanese Patent Laid-Open No. Hei 1-118529. According to the system disclosed in this official gazette, dripped granular gels are put in a Petri dish so that grains are lined up, and they are irradiated with ultraviolet radiation by a high-pressure mercury lamp while being vibrated.
Though this system realizes irradiation at a certain light intensity, it has a problem in that the production efficiency is very low because continuous production is impossible.
Moreover, the present inventor previously proposed a device for manufacturing grains by moving dripped granular gels by a transparent spiral tube and simultaneously irradiating the gels with active rays (official gazette of Japanese Patent Laid-Open No. Sho 60-106836).
The previously proposed system is described below by referring to FIG. 1. This system comprises a tank 18 for storing a liquid composition containing a photo-curable resin, polymerization initiator, and water-soluble polysaccharide capable of gelatinizing, a dripping unit 20 for dripping the liquid composition through a nozzle, and a gelatinizing vessel 22 for storing an aqueous medium containing polyvalent metal ions.
The liquid composition is supplied to the dripping unit 20 from the tank 18 through a transport tube 24. The dripping unit 20 stores a predetermined amount of liquid composition and has a nozzle 30 at the lower position so as to drip the liquid composition from the front end of the nozzle. A droplet of the liquid composition drops into the aqueous medium containing the polyvalent metal ion stored in the gelatinizing vessel 22 and is gelatinized, and, thereafter, is supplied to a light irradiation section 12 through a tube 31 connected to the bottom of the gelatinizing vessel 22.
When a liquid gel descends through a spiral transparent tube 34 together with the aqueous medium, it is irradiated with active rays emitted from an adjacently-arranged light source 32, and a photo-curable resin in particulate matter causes an optical reaction. The particulate matter, which has increased in strength due to the optical reaction, moves to a grain recovery section 14 and is stored in a recovery vessel. The aqueous medium is returned to the gelatinizing vessel 22 by a pump 48 and is repeatedly used.
This particulate matter-manufacturing system has superior advantages in that it realizes continuous production and light irradiation for a relatively long time.
However, it is clear that the system has the following problems to be solved:
(a) One light source (or more) is (or are) necessary for one tube, and the production efficiency is low. PA1 (b) Because a granular gel flows in a tube in almost a horizontal direction, the irradiation efficiency is lowered due to the screening effect because of crowded grains when there is a density difference between the a granular gel and a medium. Moreover, when the flow rate is increased to eliminate the crowdedness of grains, the tube length is increased and the system space increases. PA1 (c) When the transparent spiral tube is made of plastic, it is inferior in durability because deterioration due to ultraviolet radiation is accelerated. When the tube is made of glass, it is not easy to handle the tube when it is increased in size and the cost increases. PA1 (d) Because the batch system (taking out particulate matter when it is collected in the recovery vessel 40) is used, the particulate matter-ejecting operation is complex. PA1 (e) When taking particulate matter out of the recovery vessel 40, aqueous medium is also taken out. Therefore, it is necessary to separate the particulate matter from aqueous media and to replenish the recovery vessel with aqueous medium. PA1 a granular carrier for immobilizing microorganism cells having a surface suitable for attachment of a microorganism, characterized in that the carrier is obtained by dripping a liquid composition containing (a) a hydrophilic photo-curable resin having at least two ethylenically unsaturated bonds in one molecule, (b) photopolymerization initiator, and (c) water-soluble macromolecular polysaccharide capable of gelatinizing through contact with an alkaline metal ion or polyvalent metal ion, into an aqueous medium containing alkaline metal ions or polyvalent metal ions to gelatinize the composition, and irradiating the composition with active rays to cure it, said carrier having a specific gravity of 1.00 to 1.20, and a contact angle of 2.degree. to 30.degree. formed between the carrier surface and n-paraffin; and PA1 a particulate matter-manufacturing device comprising a gelatinizer for forming a granular gel by dripping a liquid composition containing (a) a hydrophilic photo-curable resin having at least two ethylenically unsaturated bonds in one molecule, (b) photopolymerization initiator, and (c) water-soluble macromolecular polysaccharide capable of gelatinizing through contact with an alkaline metal ion or polyvalent metal ion, into an aqueous medium containing alkaline metal ions or polyvalent metal ions to gelatinize the composition, and a light irradiator for forming particulate matter by irradiating a granular gel formed by the gelatinizer with ultraviolet radiation and curing the photo-curable resin in the granular gel, in which the light irradiator is provided with a light source and a plurality of transparent tubes which are almost vertically arranged closely to the light source, and in which the granular gel is moved. PA1 (i) Compounds having a photopolymerizable ethylenically-unsaturated group at the both ends of polyalkylene glycol such as:
In view of these problems, it is the second object of the present invention to provide a device for producing particulate matter containing a photo-curable resin as a granular carrier for immobilization, in large quantities and efficiently.

Granular carrier for immobilizing microbial cells and apparatus for producing the granular carrier


An apparatus including rigid plate having a first face and a second face, a plurality of through seats arranged as a circular crown about an axis of symmetry (A), perpendicular to each seat and shaped as a circular crown segment; a plurality of knives carried by the plate, each being axially slidingly guided into a seat, independently of the other knives; each knife has a head which protrudes from the seat from the side of the first face, a prismatic body having an axial length greater than the seat, and a wedge-shaped end, opposite to the head, which protrudes from the second face when the head substantially abuts against the first face; the wedge-shaped ends circumferentially having a first profile, complementary to that of the frontal toothing to be obtained, and the knives can be replaced totally or partially with others having a second profile different from the first profile.

According to the present invention, apparatus for forming a frontal toothing on an inner ring of a wheel hub by means of plastic deformation is thus provided.
The fact that, according to the invention, the frontal toothing is impressed by means of a plurality of knives, independently carried by a single, substantially rigid plate, and which are impressed onto the already upset collar in sequence, by moving them independently from one another by pressing respective heads of the knives by means of an orbital forming tool, surprisingly allows to obtain frontal toothings by means of plastic deformation, in which the tooth profile is kept substantially constant, while ensuring a higher dimensional accuracy of the teeth thus obtained. Therefore, better, more accurate couplings are obtained between the inner ring of the wheel hub and the constant velocity joint, which allow more effective, quieter and higher capacity torque transmissions to be obtained.
Furthermore, the required frontal toothing is obtained with low energy consumption.

Equipment for forming a frontal toothing, in particular on an inner ring of a wheel hub


A fastener assembly comprising a fastener with a head having a first surface and second surface, and a shaft extending from the second surface of the head. An annular washer is rotatably disposed about the shaft and rotatable relative to the second surface of the fastener head. The washer has an inner diameter, an outer diameter, a first surface and a second, the first surface being positioned adjacent to the second surface of the head. A plurality of identical conical projections extend out from the second surface of the washer and are formed integrally therewith.

There are a number of fasteners on the market for securing multiple structures together. In certain structural connections, however, it is important to provide an electrical connection or bond between the structures. This is particularly important in situations were a grounded condition is needed.
For example, in equipment enclosure racks, such as audio or computer equipment racks, grounding through multiple racks is generally required. Since many racks have a protective paint coating, the direct attachment using conventional nuts and bolts is not, in some cases, sufficient to provide an electrical connection. As such, in order to provide adequate grounding, separate grounding wires are typically used to provide electrical continuity. One end of the grounding wire is attached to a stud or post and the other end is attached to a grounding bus bar mounted to the rack. While this type of attachment is adequate for providing electrical grounding, the attachment of the grounding wires is time consuming and subject to error should the ground connection not be properly completed.
A product that was recently introduced by Panduit Corporation is referred to as the Tapped Rail Bonding Stud Kit and includes a nut and bolt arrangement with serrations or teeth formed integral to and on the bottom of the nut and bolt. That product is described in detail in U.S. Patent Publication No. 2006/0257229.
While the Panduit product does address the problem for breaking through the paint layer to reach the base metal, Applicant has determined that the product negatively impacts the appearance of the components and can create a corrosion source since the serrations are designed to remove a complete circular ring of paint exposing the bare metal. The ring of bare metal is susceptible to corrosion unless an anti-oxidant is applied. However, application of anti-oxidants is an additional assembly step and can be difficult to apply.

Bonding fastener assembly for electrical grounding


Various examples are directed to systems and methods for secure communication sessions between a web application and a server. A session identifier routine executing at a computing device may receive a first request message comprising a session identifier field, the session identifier field comprising a client session identifier describing a communication session between the web application executing at the computing device and the server computing device. The session identifier routine may transform the client session identifier to a server session identifier using session identifier transformation data accessed from session vault persistence at the computing device. The session identifier routine may write the server session identifier to the session identifier field of the first request message and initiate sending the request message including the server session identifier to the server computing device.

Web applications are typically executed in a web browser application to provide a user interface (UI) to a user. When executed, web applications are able to make request messages directed to remote servers. For example, web applications may request UI content from a web server, send transaction information to a merchant server, etc.


An ion implantation method is provided. The method, before ion implanting, is to rotate the substrate by an angle and shift the scan path of the ion beam with an interlace pitch in the direction perpendicular to the scan direction and on the plane of the substrate. Therefore a plurality of interlaced and not overlapped ion implantation scan lines are formed on the surface of the substrate, so the method can enhance the uniformity of the dose of the ion implantation in the substrate.

1. Field of Invention
This invention relates to an ion implantation method and, in particular, the method can improve the uniformity of ion implantation.
2. Background of the Related Art
The different stages of an implantation method according to the prior art are shown in FIG. 1a˜FIG. 1d. An ion beam scans a substrate S along a scan path to implant ions onto the substrate surface and forms a plurality of parallel ion implantation scan lines on the surface of the substrate S, that is called an ion implantation scan pass.
As shown in FIG. 1a for explaining the execution of one ion implantation scan pass, the ion beam implants ions on the substrate S along a first direction, the direction parallel to that of a first scan path 21, to form an ion implantation scan line. And then the ion beam shifts with a scan pitch T in a second direction perpendicular to the first direction. Continuously, the ion beam implants ions onto the substrate S along the reverse direction of the first direction to form another ion implantation scan line. The procedure is repeated to form a plurality of ion implantation scan lines on the substrate till the scan area covers the whole substrate S. In FIG. 1a, the plurality of ion implantation scan lines is marked 1 and the arrow mark 100 represents the orientation of the substrate S.
Next, the substrate is rotated by 90 degree on the plan of the substrate S, and the ion beam is shifted with an interlace pitch T/2 (half scan pitch) along the second direction. And then the procedure of the ion implantation scan pass is repeated to form a plurality of ion implantation scan lines 2, which is perpendicular to the direction of the plurality of ion implantation scan lines 1, and the dotted lines represent the second scan path 22 as shown in FIG. 1b.
The step shown in FIG. 1b is then further repeated two times, so as to complete the third time and the forth time of the ion implantation scan pass to form another plurality of ion implantation scan lines 1 and 2, as shown in FIG. 1c and FIG. 1d, respectively. Rotate the substrate S by 180 degree (i.e. continuous two rotations of 90 degree). The ion implantation scan lines formed by the first time of the ion implantation scan pass overlaps the ion implantation scan lines formed by the third time, and the ion implantation scan lines formed by the second time overlaps the ion implantation scan lines formed by the forth time. Therefore the third time and the forth time of the ion implantation scan pass are still marked 21 and 22, and the plurality of ion implantation scan lines formed are also still marked 1 and 2.
The dose of the ion implantation on the surface of the substrate S is illustrated in FIG. 2, where D(x) represents the distribution variation function of the dose. The larger value of D(x) is, and the worse the uniformity is. On contrary, the smaller value of D(x) is, the better the uniformity is.
For one ion implantation scan line, the farther the ion beam is away from the center of the ion implantation scan line, the smaller the dose of the ion implantation is. The first time of the ion implantation scan pass overlapping the third time of the ion implantation scan pass and the second time of the ion implantation scan pass overlapping the forth time of the ion implantation scan pass renders a larger value of the distribution variation function D(x), resulting in a poor uniformity.


A uniform method for implementing multiple tunneling protocols in a switch or router is disclosed. The method is based on the realization that although the tunneling protocols are very different, they do share a similar overall structure which can be exploited to create a unified method of dealing with multiple protocols. By using similar data structures to implement multiple protocols, the invention makes data management and programming simple and, therefore, cost effective. According to the invention, all tunneling protocols are abstracted as the mapping of input L2 or L3 streams with output L2 or L3 streams. Mapping is provided by a finite set of tunnel interfaces. The tunnel interfaces map the input streams to output interfaces. As traffic streams flow through these interfaces, they are processed according to defined attributes of these interfaces.

1. Field of the Invention
The invention relates to datacommunications. More particularly, the invention relates to methods and apparatus for tunneling different types of data packets over different types of networks.
2. State of the Art
Tunneling is a process whereby a data packet is encapsulated in another packet before traversing a network. There are two primary uses for tunneling. One use is to transport one type of packet over a network designed for another type of packet, e.g. Ethernet over ATM. Another application for tunneling is referred to as Virtual Private Networking, a process whereby a secure encrypted (or non-secure) connection is created across a public network through the use of tunneling.
Currently there are a wide variety of tunneling protocols. Some are platform and/or network dependent. Among the most popular protocols are: IP (Internet Protocol) over IP, IP over MPLS (multiprotocol label switching), Ethernet over MPLS, and L2TP (layer two tunneling protocol).
A Virtual Private Network (VPN) consists of two or more nodes connected by "virtual links", i.e. tunnels, through a public network such as the Internet. From the point of view of the nodes, the tunnel operates as a point to point link and the tunneling protocol operates as a link layer protocol.
By definition, a tunnel exists between two nodes. One node is referred to as the entry node and the other is referred to as the exit node. A tunnel is unidirectional. Bi-directional tunneling is achieved by pairing two tunnels. These are referred to as the "direct tunnel" and the "reverse tunnel". The two tunnels may traverse different nodes in the network or the tunnels may be symmetrical, i.e. traverse the same nodes in both directions.
Generally speaking, the tunneling process involves the processing of headers attached to data packets. For example, at the entry node one or more tunnel headers are pre-pended to the data packet. As the packet traverses the tunnel, intermediate nodes in the tunnel process the packet according to the tunneling protocol. For example, in IP over IP tunneling, intermediate nodes perform IP header processing and IP packet forwarding. In an MPLS tunnel, intermediate nodes perform MPLS label processing and MPLS packet forwarding. At the exit node, destination node processing is performed. For example, in an IP over IP tunnel, the exit node reassembles IP packet fragments and processes the reassembled packets according to their original (inner) headers. The processing of headers or other packet information is performed with the aid of a database. The header information is used as a key to lookup a matching entry in the database to yield an output port. The following is a more detailed explanation of how IP, MPLS, and L2TP tunneling operate.
IP over IP Tunneling
Each node in an IP tunnel maintains a "Forwarding Information Base" (FIB) which contains a plurality of entries. Each entry includes an IP address of a host or an IP prefix of one or more networks as well as information about the "Next Hop Routers" through which the destination host or network can be reached. (As used herein, the term router is meant to include switches as well as routers.) The Next Hop information consists of an IP address of the Next Hop router, the IP interface on which the Next Hop Router is reachable, and possibly more information such as a Layer 2 address. The FIB entries are typically built based on routing information disseminated dynamically by IP Routing Protocols. However, entries can also be built based on information statically configured into the router. Some routers may have multiple FIB.
IP packet forwarding is performed hop by hop. Each router in the tunnel uses the FIB information to find the best possible Next Hop router to forward an IP packet on its way to the final destination. The identity of the best possible Next Hop Router for forwarding an IP packet is determined by comparing the packet's destination IP address with the IP addresses and prefixes in the FIB. The FIB entry having the IP address or prefix which matches or most closely matches the destination IP address of the packet identifies the best possible Next Hop router. This comparison is referred to as the Longest Prefix Match. The Longest Prefix Match yields an output "IP interface" which is used to forward the packet.
The "IP interface" (IF) is an abstraction of the IP functions on a physical or logical port of a router or switch. It leads to the identification of the egress port through the binding relation with the Layer 2 interface and performs the needed IP functions to pass the packet through the port. The IF is usually configured by the router operator with information which is relevant to the IP protocol processing performed by the router.
Each router used in IP over IP tunneling also maintains an "IP Tunnel Interface" (TIF) for each tunnel serviced by the router. The TIF is an abstraction of IP over IP tunnel functions on a physical or logical port of a router. It identifies the entry and exit nodes for the tunnel. Usually, it is configured by the router operator.
Tunnels may be static or dynamic. A static tunnel uses the same set of routers and takes the same route through the network all the time. A dynamic tunnel can take different routes through the network based on network conditions or tunnel programming. Most IP tunnels are dynamic and use the best route available based on network congestion or time of day.
When a packet reaches its final destination, the exit node router strips the tunnel header(s) from the packet. The remaining inner header is an IP header, and therefore, the packet is passed to an IP processing engine which performs an IP lookup on the inner IP header, i.e. the IP destination address. This lookup may yield an outgoing interface, if the packet is to be forwarded, or may indicate local consumption, if the router itself is the final destination. The router itself may be the final destination when the packet contains command/control information.
MPLS Tunneling
The key concept in MPLS tunneling is identifying and marking packets with labels and forwarding them to a router which then uses the labels to forward the packets through the network. The labels are created and assigned to packets by a Label Distribution Protocol (LDP) based upon the information gathered from existing routing protocols or some other method.
An MPLS tunnel includes a plurality of interconnected Label Switch Routers (LSRs). At least some of the LSRs are coupled to Label Edge Routers (LERs). An MPLS tunnel is also referred to as a Label Switched Path (LSP) from an input LER through LSRs to an output LER. When a packet arrives at an LER, the LER extracts the datagram (the data portion of a packet) and the routing information from the packet and assigns a label to the datagram based on routing information. The datagram with the label is then sent to an LSR based on the label. The LSR which receives the datagram forwards it on through the network based on the label.
An LSP is a set of LSRs that packets belonging to a certain FEC (forwarding equivalence class) travel in order to reach their destination. Each LER in an MPLS tunnel (LSP) has an Incoming Label Map (ILM). The ILM specifies the action to take when a labeled packet is received. Each entry defines an incoming label, a label operation, and a link to a Next Hop Label Forwarding Entry (NHLFE). The ILM is built based on label distribution information disseminated by a Label Distribution Protocol (LDP) engine.
Each LER in the MPLS tunnel (LSP) has an FEC-to-NHLFE Map (FTN). The FTN specifies the action to take when an unlabeled packet is received. Each entry in the FTN defines a set of characteristics used to categorize the packet, and a link to an NHLFE. The FTN is also built based on information disseminated by a Label Distribution Protocol (LDP) engine.
An NHLFE specifies "how to" forward a packet. It defines an outgoing label, a label operation, a next hop IP address, and an output interface. It may also specify an MPLS label stack. The label stack identifies a series of labels to push on a labeled packet in the process of forwarding the packet on an LSP segment. The NHLFE is built based on label distribution information disseminated by a Label Distribution Protocol (LDP) engine.
Simple label forwarding is realized by pointing an ILM entry to an NHLFE, and applying a label swap. This is referred to as the MPLS label swapping/forwarding function. An LSP is originated by pointing an FTN entry to a NHLFE, and applying a label push. This is referred to as the LSP entry function. An LSP is terminated by not pointing an ILM entry to any NHLFE, and applying a label pop at input. Terminating the LSP does not guarantee that the packet will be consumed by the local node. The packet is forwarded using the exposed label or IP header. The collection of ILMs and related NHLFEs are collectively called the MPLS Label Information Base or LIB.
L2TP Tunneling
The L2TP (layer two tunneling protocol) is an extension to PPP (point-to-point protocol) that enables ISPs to operate Virtual Private Networks (VPNs). L2TP works with UDP (user datagram protocol) and IP drivers. L2TP uses a "tunnel list" which is analogous to an MPLS LIB. When a packet is received front a PPP link, part of the PPP header is stripped off and replaced with an L2TP header which includes tunnel and session IDs. The packet is sent to an L2TP tunnel by writing to a UDP driver with IP interface data and the end point IP address. At the end of the tunnel, data is read from a UDP port. The tunnel ID, session ID, and packet flags are extracted. The data is then formatted and written to a PPP link associated with the session. L2TP provides a "one hop" virtual PPP link which spans a multi-hop IP path.
From the foregoing it will be appreciated that the different tunneling protocols process packets in very different ways. State of the art routers which are intended to support different types of tunneling have separate processing engines for each supported tunneling protocol. Depending on the number of tunneling protocols to be implemented, the router may not be cost effective from the perspective of resources, design time and maintainability.

Methods and apparatus for implementing multiple types of network tunneling in a uniform manner


Apparatus and methods according to the present invention preferably utilize electroosmotic pumps that are capable of generating high pressure and flow without moving mechanical parts and the associated generation of unacceptable electrical and acoustic noise, as well as the associated reduction in reliability. These electroosmotic pumps are preferably fabricated with materials and structures that improve performance, efficiency, and reduce weight and manufacturing cost relative to presently available micropumps. These electroosmotic pumps also preferably allow for recapture of evolved gases and deposited materials, which may provide for long-term closed-loop operation. Apparatus and methods according to the present invention also allow active regulation of the temperature of the device through electrical control of the flow through the pump and can utilize multiple cooling loops to allow independent regulation of the special and temporal characteristics of the device temperature profiles. Novel microchannel structures are also described.

Electronic systems, including, for example, laptop, hand-held and desktop computers as well as cell phones operate through the use of input electrical power. These have the characteristic that some of the input power is converted to heat, and the heat generated-is typically concentrated in an identifiable area, such as an integrated circuit chip or a circuit board. Such devices and products incorporate heat sinks, fans, heat-pipes, refrigeration, and cooling water as needed to regulate their operating temperature within specific ranges.
It is predicted that electronic devices currently under development will generate heat at total rates and spatial densities exceeding the cooling capabilities of conventional heat sinking technology. For example, technology targets set by the semiconductor industry and summarized by the International Technology Roadmap for Semiconductors indicate the need to remove as much as 200W from the surface of a microprocessor before the year 2007. The trends towards higher total power and power density are similarly extreme in the optical telecommunications industry, the power electronics industry, and elsewhere. Conventional heat sinks are simply incapable of removing the targeted powers and power densities within a volume consistent with system design and market expectations.
This situation is exacerbated by targeted reductions of total system volume, which diminish the volume and surface area available for cooling devices. The interaction of these two trends (increasing head load and decreasing system volume) are recognized as a critical problem for the future of the semiconductor industry, and for other industries that rely on heat-generating or absorbing devices.
Conventional techniques for removing heat from devices include a number of well-established technologies.
Heat Sinks generally consist of metal plates with fins that transport heat from the device to the surrounding air by natural or forced convection. The heat sink fins serve to increase the area of contact between the device and the air, thereby increasing the efficiency of the heat transfer. Heat sinks of many materials, geometries, and constructions have been known for more than 50 years.
Fans consisting of rotating blades driven by electric motors can enhance the heat transfer between a heat sink and the surrounding air by causing the air to circulate around and through the heat sink with greater velocity than that which results from natural convection.
Fans have been used for cooling systems for more than 30 years. Integration of fans with heat sinks for cooling of devices which generate large quantities of heat have been developed by many inventors, and are in wide use.
Heat pipes consist of a hollow tube which incorporates a wicking structure, and is partially filled with liquid. One end of the heat pipe is placed in contact with the heat-generating device. At this end of the heat pipe, the liquid evaporates, and vapor travels down the hollow center of the pipe to the other end. This end is placed into contact with a cold medium, or a heat sink, or is in contact with the surrounding air, and acts to cool the vapor in the center of the tube to the condensation temperature. This liquid, after condensation, is transported back to the hot end of the tube by capillary forces within the wicking structure. Heat pipes can offer significantly better heat conduction than solid metal rods of the same dimensions, and are widely used in many applications. Heat pipes are presently used for heat removal in electronic products, spacecraft, and a variety of other applications where heat generation in compact geometries is of interest. Heat pipes may be formed in many geometric structures, and may be integrated into the device package for efficient heat transport (U.S. Pat. No. 5,216,580), or may be used to deliver heat some distance away through a flexible coupling (U.S. Pat. No. 5,560,423). Vapor chambers closely resembles a heat pipe in operating principle and dimensions, but generally has a rectangular (rather than tubular) cross-sectional shape and can involve varying geometrical placements of the wicking structure. Both heat pipes and Vapor chambers are subject to the same basic physical limit for the peak power: The longer the separation between the heat source and the heat sink, and the smaller the cross sectional area, the smaller the total heat power that can be removed before these devices reach the capillary limit, or dry-out, condition.
Active cooling of a device via a vapor-compression cycle or by thermoelectric or other solid-state cooling devices is used in some high-performance thermal control applications, or where regulation at low temperatures is required. In these applications, the heat from the device is transported to the rejection surface, and significant excess heat is added due to the limited thermodynamic efficiency of the cooling mechanism. The rejection surface must generally be cooled by one of the other means described herein. Vapor-Compression refrigeration cycles have been used in many applications ranging from home air-conditioning and kitchen refrigeration to spacecraft and cryogenic systems for many years.
Cooling water is used in situations where large quantities of heat are generated, and the other methods described herein are unable to reject the heat to the surrounding air. In this case, a continuous supply of cool water is required, and this cool water is passed around or through the device or channels in an attached structure. Thereafter, the warmer water is returned to the waste water system.
In miniaturized applications employing cooling water techniques exist which address the problem of miniaturized microchannel cooling systems, miniaturized, closed-loop cooling systems, and systems which rely on active pumping of fluids to achieve cooling. Microchannel heat exchangers were originally explored by Tuckerman et al. (U.S. Pat. No. 4,450,472, U.S. Pat. No. 4,573,067) in the early 1980s. These devices contained straight, uniform-cross-section microfabricated channels within a silicon substrate, through which liquid coolant was passed. Subsequent patents followed the original work of Tuckerman and Pease (U.S. Pat. No. 4,450,472), including descriptions of microchannel fabrication methods, attachment methods, and specific materials and designs for specific applications.
Microchannel heat sink design to achieve higher heat transfer coefficients or improved temperature uniformity has also been explored. Phillips (U.S. Pat. No. 4,894,709) described liquid microchannel cooling with a guard header structure to improve temperature uniformity in the chip. Frieser (U.S. Pat. No. 4,312,012) described modifications of the surface of the microchannel to improve nucleate boiling and the heat transfer coefficient. Swift (U.S. Pat. No. 4,516,632) and Walpole (U.S. Pat. No. 5,099,910) described channels with alternating flow directions to improve temperature uniformity. Lomolino (U.S. Pat. No. 5,427,174) used a two-fluid mixture to control the effective heat capacity of the coolant and turbulence over a targeted temperature range.
Closed-loop cooling systems employing microchannels have also been an active area of research in recent years, including the description by Hamilton (U.S. Pat. No. 5,901,037) of a closed-loop cooling system in which fluids are passed through microchannels attached to the integrated circuit, and a magnetic pump generates the pressure. Further, Davis (U.S. Pat. No. 5,703,536) describes the use of a closed loop fluidic cooling system for cooling of high-power RF transmitters.
There has been extensive research into the development of micropumps. These research efforts include pumps based on oscillating piezoelectric membranes, peristaltic pumps, electrohydrodynamic pumps, and others. These pumps, to date, appear to be incapable of generating the pressure and/or flow necessary for application to removal of high heat flux from high-power devices.
The phenomenon of electro-osmosis has been known since the work of F. F. Reuss in 1809. A simple description of this phenomenon is that liquid flow is induced on a region of net charge that develops at the liquid/wall interface. The magnitude of the force is proportional to the applied electric field, and the quantity of the charged species available in this region of net charge. Larger flow rates can be achieved for systems with large cross-sectional areas. Large pressure generation requires structures with very high surface-t0-volume ratio.
Miniature pumps based on the phenomenon of Electro-Osmosis (i.e., Electroosmotic pumps) were originally developed by Theeuwes (U.S. Pat. No. 3,923,426), in which a porous ceramic structure was used to provide a multitude of micron-sized pathways with charged surface layers. Theeuwes describes the importance of selecting pumping structures which feature high porosity, high electroosmotic mobility for a given working fluid, small diameter pores, and discusses the possibility of the use of quartz or glass ceramics, possibly comprised of beads, and porous polymer matrices. The working fluid in the Theeuwes pump was suggested to have a high dielectric constant, low viscosity, and low electrical conductivity. Example liquids that the Theeuwes pump used include deionized water, ethyl-alcohol and alcohol-water mixtures, and many organic solutions. With these materials and solutions, flow rates in excess of 1 mL/min and pressures exceeding 1 Atmosphere were reported.
Despite the many different and diverse cooling systems and techniques described above, there exists a need for an improved closed-loop, fluidic cooling systems and techniques for high power applications having the capability of being implemented in a miniaturized environment. In addition, there exists a need for an improved miniature fluidic cooling system having feedback-controlled temperature regulation of devices that facilitates, for example, hotspot cooling by way of, for example, active regulation of the temperature of the integrated circuit device through electrical control of the flow through the pump. Such miniature fluidic cooling system may utilize multiple cooling loops (in conjunction with multiple pumps) to allow independent regulation of the special and temporal characteristics of the device temperature profiles.
Moreover, there exists a need for a miniature pump that is capable of generating the high pressure (for example, pressure greater than 10 PSI) and/or high flow (for example, a flow rate greater than 5 ml/min) that are necessary for the removal of the predicted high heat flux (for example, power greater than 100W). Such a pump should overcome or address the shortcomings of the conventional pumps, for example a pump configuration for use in a closed-loop systems that addresses practical issues involving evolved gases (for example, by way of recapture) or deposited materials. These issues tend to be prominent in closed-loop fluidic cooling systems employing pumps.

This patent is subject to a terminal disclaimer.

Electroosmotic microchannel cooling system

The Board of Trustees of the Leland Stanford Junior Universty


A polymeric material such as polyurethane, PET, or ePTFE is used to cover an intravascular stent. The cover material has an overlapping portion which is slidable upon itself so that when the stent is expanded, the cover material does not contribute to stent foreshortening, if any. The cover material can be provided with holes to permit endothelialization and can be drug loaded to facilitate repair of a damaged vessel.

The present invention relates generally to expandable endoprosthesis devices, generally called stents, which are adapted to be implanted into a patient's body lumen, such as a blood vessel, to maintain the patency thereof, and more particularly to covered vascular stents which can minimize plaque prolapse that can occur between the struts of the stent and can help prevent the formation and release of embolic debris into the body lumen. Stents are particularly useful in the treatment and repair of blood vessels after a stenosis has been compressed by percutaneous transluminal coronary angioplasty (PTCA), percutaneous transluminal angioplasty (PTA), or removed by atherectomy or other means, to help improve the results of the procedure and reduce the possibility of restenosis. Stents also can be used to provide primary compression to a stenosis in cases in which no initial PTCA or PTA procedure is performed. While stents are most often used in the procedures mentioned above, they also can be implanted in any body lumen or vessel such as the urethra, esophagus and bile duct and the like.
In typical PTCA procedures, a guiding catheter or sheath is percutaneously introduced into the cardiovascular system of a patient through the femoral arteries and advanced through the vasculature until the distal end of the guiding catheter is in the aorta. A guide wire and a dilatation catheter having a balloon on the distal end are introduced through the guiding catheter with the guide wire sliding within the dilatation catheter. The guide wire is first advanced out of the guiding catheter into the patient's vasculature and is directed across the arterial lesion. The dilatation catheter is subsequently advanced over the previously advanced guide wire until the dilatation balloon is properly positioned across the arterial lesion. Once in position across the lesion, the expandable balloon is inflated to a predetermined size with a radiopaque liquid at relatively high pressure to displace the atherosclerotic plaque of the lesion against the inside of the artery wall and thereby dilate the lumen of the artery. The balloon is then deflated to a small profile so that the dilatation catheter can be withdrawn from the patient's vasculature and the blood flow resumed through the dilated artery. As should be appreciated by those skilled in the art, while the above-described procedure is typical, it is not the only method used in angioplasty.
In angioplasty procedures of the kind referenced above, abrupt reclosure may occur or restenosis of the artery may develop over time, which may require another angioplasty procedure, a surgical bypass operation, or some other method of repairing or strengthening the area. To reduce the likelihood of the occurrence of abrupt reclosure and to strengthen the area, a physician can implant an intravascular prosthesis for maintaining vascular patency, commonly known as a stent, inside the artery across the lesion. Stents are generally cylindrically shaped devices which function to hold open and sometimes expand a segment of a blood vessel or other arterial lumen, such as coronary artery. Stents are usually delivered in a compressed condition to the target location and then are deployed into an expanded condition to support the vessel and help maintain it in an open position. The stent is usually crimped tightly onto a delivery catheter and transported in its delivery diameter through the patient's vasculature. The stent is expandable upon application of a controlled force, often through the inflation of the balloon portion of the delivery catheter, which expands the compressed stent to a larger diameter to be left in place within the artery at the target location. The stent also may be of the self-expanding type formed from, for example, shape memory metals or super-elastic nickel-titanum (NiTi) alloys, which will automatically expand from a compressed state when the stent is advanced out of the distal end of the delivery catheter into the body lumen.
Details of prior art expandable stents can be found in U.S. Pat. No. 3,868,956 (Alfidi et al.); U.S. Pat. No. 4,512,338 (Balko et al.); U.S. Pat. No. 4,553,545 (Maass, et al.); U.S. Pat. No. 4,733,665 (Palmaz);. U.S. Pat. No. 4,762,128 (Rosenbluth); U.S. Pat. No. 4,800,882 (Gianturco); U.S. Pat. No. 5,514,154 (Lau, et al.); U.S. Pat. No. 5,421,955 (Lau et al.); U.S. Pat. No. 5,603,721 (Lau et al.); U.S. Pat. No. 4,655,772 (Wallsten); U.S. Pat. No. 4,739,762 (Palmaz); and U.S. Pat. No. 5,569,295 (Lam).
Further details of prior art self-expanding stents can be found in U.S. Pat. No. 4,580,568 (Gianturco); and U.S. Pat. No. 4,830,003 (Wolff, et al.).
The above-described, non-surgical interventional procedures, when successful, avoid the necessity for major surgical operations. However, a danger which is always present during these procedures is the potential for particles of the atherosclerotic plaque, which can be extremely friable, breaking away from the arterial wall. For example, during deployment of a stent, the metal struts of the stent can possibly cut into the stenosis and shear off pieces of plaque which become embolic debris that will travel downstream and lodge somewhere in the patient's vascular system. When any of the above-described procedures are performed in the carotid arteries, the release of emboli into the circulatory system should be avoided. Debris that is carried by the bloodstream to distal vessels of the brain can cause these cerebral vessels to occlude, possibly resulting in a stroke. Therefore, although cerebral percutaneous transluminal angioplasty has been performed in the past, the number of procedures performed has been limited due to the fear of causing an embolic stroke should embolic debris enter the bloodstream and block vital downstream blood passages. Embolization in other vasculature may induce possible acute myocardial infraction when a procedure is performed on the coronary arteries and gangrene when performed in peripheral arteries, such as the arms and legs.
While stents are helpful in holding open otherwise blocked or occluded vessels, the stent does have an open structure of struts and spines which cooperatively provide the scaffolding necessary to maintain the vessel open at the site of treatment. Due to the open nature of the stent structure, there is a possibility that growth material can pass through the openings between the struts and extend into the inner lumen of the stent structure. For example, excessive cell or tissue growth (intimal hyperplasia) can cause partial restenosis to develop over time, which is detrimental to the patient. The tissue or cell growth can extend into the tubular opening created by the stent and can block or otherwise re-occlude the opening and can possibly cause abnormal blood flow through the stent which can cause formation of thrombi that are detrimental to the patient's health.
Prior art devices have been created to help reduce the passage of such growth through the wall of the deployed stent, including a stent covering which surrounds the open stent. In this manner, the gaps between the stent struts can be covered to prevent material, such as plaque, from prolapsing between the struts. Coverings have included a variety of materials such as ePTFE, autologous vein grafts, pericardium and fibrin. The covering should be sufficiently flexible and expandable to allow the stent to deploy from its collapsed or compressed position to a fully expanded position.
Covered stents also help prevent the struts from cutting into the plaque of the stenosis which helps reduce the possibility of forming embolic debris that can be released into the blood stream, as described above. Moreover, in the event that any embolic debris may be created from the expansion of the stent, the covering could trap the embolic particles against the arterial wall, thus preventing the particles from being released into the bloodstream.
Some prior art covered stents are difficult to manufacture due to the flexibility of the covering and the requirement that the covering be capable of expansion when the stent is deployed within the patient's vasculature. For these reasons, the material used to form the covering may be subjected to intricate processing to obtain the desired flexibility for the covering and to attach the covering to the stent. A covering which does not expand normally can cause the stent to misalign within the body vessel and can cause an non-uniform deployment of the stent. Moreover, some coverings are made from a sheet of material which is rolled into a cylindrical shape by creating a longitudinal seam which runs along the length of the covering and then the covering is attached to the stent. Such coverings can be more susceptible to tearing, especially at the seam, when the stent is expanded.
Some prior art stents that are covered may have a tendency to shorten when expanded and the covered material also shortens, providing an undesirable result. As the stent and the covered material are expanded into contact with an artery or vessel wall, the shortening movement may scrape along the artery wall and cause injury or dislodge plaque material which may embolize. Further, as these prior art covered stents shorten upon expansion, the cover material shortens past the stent struts at the stent ends, leaving a covered stent with exposed stent struts, and not fully covered upon expansion.
Thus, it would be desirable to have a covered vascular stent in which the covering has sufficient expandability and flexibility and can be formed with a thin wall which does not dramatically increase the delivery profile of the device. Such a covered stent should be relatively easy to manufacture as well and it should not affect the stent's ability to be fully deployed within the patient's vasculature. The present invention satisfies these and other needs.

Covered stent assembly for reduced-shortening during stent expansion


Circular stapling instruments for cutting and applying one or more surgical staples to tissue are disclosed. The instruments include various forms of anvil locking systems designed to selectively prevent the anvil from moving axially relative to the stapling head of the stapling instrument. One embodiment employs an elongated gear rack that is selectively engagable with locking gears to prevent axial motion of the elongated gear rack and an adjustment shaft used to axially position the anvil. Other embodiments employ a gear assembly that cooperates with the elongated gear rack. A locking member is movably supported by a handle assembly that houses the gear assembly and elongated gear rack. The locking member is configured for selective meshing engagement with the gear assembly to ultimately prevent axial movement of the gear rack and adjustment shaft.

In certain types of surgical procedures, the use of surgical staples has become the preferred method of joining tissue and, as such, specially configured surgical staplers have been developed for these applications. For example, intra-luminal or circular staplers have been developed for use in a surgical procedure known as an anastomosis. Circular staplers useful for performing an anastomosis are disclosed, for example, in U.S. Pat. Nos. 5,104,025; 5,205,459; 5,285,945; and 5,309,927 which are each herein incorporated by reference in their respective entireties.
One form of an anastomosis comprises a surgical procedure wherein sections of intestine are joined together after a diseased portion has been excised. The procedure requires re-joining the ends of the two tubular sections together to form a continuous tubular pathway. Previously, this surgical procedure was a laborious and time consuming operation. The surgeon had to precisely cut and align the ends of the intestine and maintain the alignment while joining the ends with numerous suture stitches. The development of circular staplers has greatly simplified the anastomosis procedure and also decreased the time required to perform an anastomosis.
In general, a conventional circular stapler typically consists of an elongated shaft that has a proximal actuating mechanism and a distal stapling mechanism mounted to the shaft. The distal stapling mechanism commonly consists of a fixed stapling cartridge that contains a plurality of staples configured in a concentric circular array. A round cutting knife is concentrically mounted in the cartridge interior to the staples for axial travel therein. Extending axially from the center of the cartridge is a movable trocar shaft that is adapted to have a staple anvil removably coupled thereto. The anvil is configured to form the ends of the staples as they are driven into it. The distance between a distal face of the staple cartridge and the staple anvil is controlled by an adjustment mechanism mounted to the proximal end of the stapler shaft for controlling the axial movement of the trocar. Tissue clamped between the staple cartridge and the staple anvil is simultaneously stapled and cut when the actuating mechanism is activated by the surgeon.
When performing an anastomosis using a circular stapler, the intestine is typically stapled using a conventional surgical stapler with double rows of staples being emplaced on either side of the diseased portion of intestine to be removed. The target section is simultaneously cut as the adjoining end is stapled. After removing the diseased portion, the surgeon typically inserts the anvil into the proximal end of the lumen, proximal of the staple line. This is done by inserting the anvil head into an entry port cut into the proximal lumen by the surgeon. On occasion, the anvil can be placed transanally, by placing the anvil head on the distal end of the stapler and inserting the instrument through the rectum. The surgeon then ties the proximal end of the intestine to the anvil shaft using a suture or other conventional tying device. Next, the surgeon cuts excess tissue adjacent to the tie and the surgeon attaches the anvil to the trocar shaft of the stapler. The surgeon then closes the gap between the anvil and cartridge, thereby clamping the proximal and distal ends of the intestine in the gap. The surgeon next actuates the stapler causing several rows of staples to be driven through both ends of the intestine and formed, thereby joining the ends and forming a tubular pathway. Simultaneously, as the staples are driven and formed, the concentric circular knife blade is driven through the intestinal tissue ends, cutting the ends adjacent to the inner row of staples. The surgeon then withdraws the stapler from the intestine and the anastomosis is complete.
During the above-described surgical procedures, the clinician generally strives to obtain a tight enough staple line to prevent leakage and bleeding and to achieve "tissue-to-tissue" contact which promotes tissue healing. In general, by controlling the amount of compression that is applied to the tissue, better stapling and healing results will be achieved. Achieving a desired amount of tissue compression becomes challenging when dealing with thick tissues and thin tissues. For example, when stapling thinner tissue, it is necessary to move to the lower end of the compression range to obtain compression of the tissue—without over compressing it. When stapling thicker tissues, the proper compression will be achieved at a larger gap setting.
A simple robust means to measure this compression would be to use a compliant member and an indicator to measure displacement similar to a spring force scale. Such arrangements, however, must be able to withstand the forces required to form the staples and to cut through a break away washer which is commonly mounted in the anvil. In some instances, for example, such forces may exceed 300 lbf and must be restrained without deflection to ensure the proper formed staple height is achieved. Such devices, however, present additional challenges to the user. In particular, once the anvil has been properly positioned, it is necessary that the anvil not move during firing. Those anvil systems that are compliant in nature may facilitate undesirable movement or deflection of the anvil during firing which could adversely affect proper staple formation.
Thus, the need exists for an anvil locking system that can be used to selectively retain the anvil in a desired position during stapling.
The foregoing discussion is intended only to illustrate some of the shortcomings present in the field of the invention at the time, and should not be taken as a disavowal of claim scope.

Circular surgical stapling instrument with anvil locking system


Equipment for monitoring the performance of an engine fuel injector valve includes a source of pressurized fluid and an injector valve head connected to an injector valve and the source so that pressurized fluid is delivered to the valve. A regulator compensates for changes in pressure of the fluid and enables the change to be effected and maintained. A flow monitor is in the fluid path between the source and the head to monitor the flow of fluid. The source of pressurized fluid maintains a level of pressure in excess of a desired operating pressure. A fluid flow control coupled to a pressure sensor, near the test head indicates the pressure therein so that the flow control effects flow through the fluid path to maintain the pressure at the head.

This application claims priority under 35 U.S.C. 119 to the foreign application number 9930120.2, filed on Dec. 21, 1999 in United Kingdom.
The present invention relates to monitoring equipment for monitoring the performance of an engine fuel injector valve, comprising a source of pressurized fluid and an injector valve head provided with connection means to enable an injector valve to be connected thereto, the head being connected to the source so that pressurized fluid from the source is delivered to the injector valve when the equipment is in use, there being regulator means of the equipment to compensate for changes in pressure of the fluid at the head owing to pulsed operation of the injector valve when the equipment is in use, as well as to enable a change in pressure to be effected and maintained at the head, and flow monitoring means in the fluid path between the source and the head to monitor the flow of fluid to the head.
Hitherto, air piloted pressure regulators have been used as the regulator means. However, such equipment has suffered from a relatively slow response time to pressure changes, especially because of the use of air as the control medium. This results in an undesirable level of hysteresis using such equipment.
The present invention seeks to obviate this disadvantage.
Accordingly, the present invention is directed to monitoring equipment having the construction set out in the opening paragraph of the present specification, in which the source of pressurized fluid is such as to maintain a level of pressure in excess of a desired operating pressure, and in which the regulator means comprises fluid flow control means coupled to a pressure sensor, which is in or near the test head to provide an indication of the pressure therein so that the flow control means effects an increase or a decrease to flow of fluid through the said fluid path to maintain the pressure of the fluid at the head substantially at the desired operating pressure.
Preferably, the flow control means comprises a hydraulic amplifier arranged to operate valve means of the flow control means so as to effect such increase or decrease.
An especially fast response to changes of pressure is obtainable if the flow control means comprises a first movable member, transducer means which serves to provide a force which acts on and moves the first movable member in dependence upon the magnitude of an input signal delivered to the flow control means, two inputs connected to deliver pressurized fluid to opposite sides respectively of the first movable member and to opposite sides respectively of a second movable member, and output means from which fluid flows after it has reached the first movable member, in such a manner that movement of the first movable member in a first direction increases the resistance to flow of fluid from one of the two inputs to the said output means, so that pressure of fluid from that input urges the said second movable member in a given direction, whilst movement of the first movable member in a second direction, opposite to the first, increases the resistance to flow of fluid from the other of the said two inputs to the said output means, so that pressure of fluid from that other input urges the said second movable member in another direction opposite to the said given direction, the flow control means further comprising balancing means to balance the movement of the second movable member against the said force, and valve means which are opened to an extent which is dependent upon the position of the second movable member, whereby the extent to which the valve means is opened is dependent upon the magnitude of the input signal, so that the latter effects such increase or decrease.
Advantageously, the pressurized fluid delivered by the said two inputs is the pressurized fluid from the said source.
Preferably, the balancing means comprise a spring.
The valve means of the flow control means is preferably a slide valve, for example a spool valve.

Monitoring equipment for monitoring the performance of an engine fuel injector valve