Abstract: A four stroke diesel engine combined with a supercharger is operable to supply varying amounts of air to the engine responsive to the load on the engine. The supercharger has a pair of rotors driven by the engine operable to move air to the engine. Gates associated with the rotors control the amount of air and pressure of the air moved by the rotors to the diesel engine.

Abstract: A hydraulic control unit provided with oil pumps includes a first oil discharging outlet and a second oil discharging outlet, a high pressure route connected with the first oil discharging outlet, a medium pressure route with an oil pressure therein being lower than that in the high pressure route, a low pressure route with an oil pressure therein being lower than that in the medium pressure route, and a connection mode switching mechanism for selectively connecting a second oil discharging outlet with the high pressure route, the medium pressure route or the low pressure route. The connection mode switching mechanism includes a changeover valve selectively connecting the second oil discharging outlet with the medium pressure route or the low pressure route; and a changeover valve controlling device connecting the second oil discharging outlet with any of the medium pressure route and the low pressure route. The hydraulic control unit can minimize drive loss of an oil pump.

Abstract: A pump having a housing with an actuator member positioned inside for controlling the flow generated by the pump. A first decrease port is connected to the housing and has a surface area in operable contact with the actuator member. A second decrease port is connected to the housing and has a surface area that is operable contact with the actuator member. A valve is connected to the second decrease port for controlling the flow of fluid to the second decrease port. A suction passage is connected to the housing and drawings fluid to the housing using the actuator member. A discharge passage is connected to the housing so that fluid providing an exit for fluid that has been pressurized by the actuator member.

Abstract: A compressed air supply system for a utility vehicle includes a compressed air inlet that can be coupled to a compressor, a filter unit that can be coupled to the compressed air inlet via a supply line, a discharge valve element that is coupled to a discharge outlet and the supply line, an energy-saving control outlet that can be coupled to a control inlet of the compressor, a supply line locking valve element interposed between the compressor and the filter unit and a first valve element and a second valve element, the discharge valve element, the energy saving control outlet, the regeneration of the filter unit and the supply line locking valve element being controllable by the valve elements. The energy saving control outlet can be controlled by the first valve element and the discharge valve element and the regeneration of the filter unit can be controlled by the second valve element.

Abstract: A valve arrangement for placing a supply of motive fluid in alternating communication with first and second motive fluid chambers. The valve arrangement includes a power valve including a supply chamber, a pilot chamber, and a shiftable member separating the supply chamber from the pilot chamber. The valve arrangement also includes a pilot valve actuable between an on condition in which the pilot valve generates a pilot signal that shifts the power valve, and an off condition in which the pilot valve does not generate the pilot signal. At least a portion of the pilot valve is exposed to motive fluid, and the portion of the pilot valve exposed to motive fluid includes surface areas giving rise to a net zero actuating force arising from pressure of the motive fluid. Because there is no biasing force on the pilot valve, the pilot valve is shifted between the on and off conditions without significant resistance.

Abstract: A pump system includes pump having a control feature which, responsive to a supply of pressurized working fluid, reduces the pressure of the working fluid pressurized by the pump. The control feature is connected to the output of the pump by a regulating valve. The control feature receives pressurized working fluid to decrease the output of the pump in response to the pressure of the supplied working fluid. A regulating valve selectively connects the pressurized working fluid to the control feature. The regulating valve has a control port to receive pressurized working fluid from the pump to urge the valve to a closed position against a biasing force. A controllable valve is operable to interrupt the supply of pressurized working fluid to control port to alter the output pressure of the pump.

Abstract: The present invention provides a hydraulic pump for use in driving a load with a control modulation system which modulates a primary control signal in order to accommodate variations in secondary changeable parameters which require control at a higher frequency or have a lower latency.

Abstract: An air supply apparatus A includes an air pump 20 capable of supplying compressed air to an air chamber (a tire air chamber Ra of a wheel B) on the basis of rotation of the wheel B; a change valve 30 provided outside a pump chamber Ro of the air pump 20 and adapted to restrict the supply of compressed air from the pump chamber Ro to the air chamber when the pressure of compressed air supplied from the pump chamber Ro to the air chamber reaches a first set value; and an adjustor 40 capable of adjusting the first set value.

Abstract: An oil supplying apparatus for a vehicle, includes an engine driven mechanical oil pump, a hydraulic actuator operated by pressure of oil supplied from the engine driven mechanical oil pump to the hydraulic actuator, an engine lubrication device lubricating each member of the engine with the oil supplied from the engine driven mechanical oil pump, and a priority flow valve selectively establishing priority flow and secondary flow conditions when a low oil pressure is working on the hydraulic actuator and when a high oil pressure is working on the hydraulic actuator, respectively, the priority flow condition allowing an oil supply from the engine driven mechanical oil pump to the hydraulic actuator with priority over an oil supply from the engine driven mechanical oil pump to the engine lubrication device, the secondary flow condition allowing the oil supply from the engine driven mechanical oil pump to the engine lubrication device.

Abstract: A variable displacement compressor with a discharge pressure compensated suction shutoff valve (SSV). The SSV prevents noise generated at low refrigerant flow rates by a suction valve from propagating out of the compressor and to an air conditioner evaporator by variably restricting a fluid communication with the suction valve. The SSV is configured so the variable restriction is increased correspondingly with the discharge pressure if the discharge pressure is less than a threshold that is an indicator of low refrigerant flow rates, and the restriction is decreased if the discharge pressure is greater than the threshold.

Abstract: An integrated pumping module for use in a thermal management system, for example for a fuel cell. The integrated pumping module includes a diverting or mixing valve closely coupled to a pump element, such as the volute chamber of a centrifugal pump. The valve chamber and the pump chamber are closely and directly coupled through a connecting passage so as to minimize pressure drop as a liquid coolant passes through the connecting passage from the valve chamber to the pump chamber. A bypass inlet and outlet opening are provided in the valve chamber to permit all or a portion of the coolant flow to be diverted to a radiator once the coolant reaches a predetermined temperature. The integrated pumping module may also be provided with a filter housing into which a portion of the coolant flow may be diverted.

Abstract: Apparatus and a method are provided for inhibiting the propagation of a flame front that is ignited by a pumping mechanism which draws a waste stream from a process chamber. The apparatus comprises a foreline for conveying the waste stream which is drawn from the process chamber to the pumping mechanism. The foreline comprises an isolation valve for selectively isolating the pumping mechanism from the process chamber and a bypass positioned around the isolation valve. The apparatus further comprises a controller for actuating the isolation valve. The controller is configured to cause the isolation valve to be closed when the waste stream is initially drawn from the process chamber. During which time the waste stream is conveyed to the pumping mechanism via the bypass, the bypass comprises means for inhibiting propagation of a flame front therethrough.

Abstract: Method for controlling a compressed air unit (1) comprising one or several compressed air networks, as well as a number of communicating controllers (6, 9, 13, 23, 24, 25 or 26) for controlling components that are part of the aforesaid compressed air networks, characterised in that the control of the above-mentioned components is such that none of the communicating controllers (6, 9, 13, 23, 24, 25 or 26) determines the operational condition of any component that is controlled by other controllers.

Abstract: Equipment for continuous regulation of the flow rate for a reciprocating compressor, provided with at least one compression chamber (1) in which is slidably inserted a piston means (101) movable with a reciprocating motion, at least one inlet valve (2) for the fluid to be compressed and at least one outlet valve (4) for the compressed fluid being provided in the said chamber, the said outlet valve (4) being connected to a storage reservoir (10) for the compressed fluid, and the said inlet valve (2) being provided with translation means (502, 512) which can act on the obturator (302) of the said valve (2), the said translation means (502, 512) being movable in a direction perpendicular to the plane of the said obturator (302), and interacting with actuator means (3, 103, 203) which are movable in the said direction with a reciprocating motion by means of suitable operating means (303, 403); the said operating means (303, 403) make it possible to control the velocity of displacement of the said actuator means (

Abstract: A vehicle, such as a lorry or a bus, includes compressed air consuming devices and a power driven compressor to deliver compressed air to at least one storage tank. A control device controls the operation of the compressor so as to maintain the air pressure in the tank at a desired pressure level sufficient to operate the air consuming devices, such as a braking system and a suspension system, when needed. The air pressure is usually maintained substantially at a predetermined first elevated level or value.

Abstract: A dynamoelectric machine that has at least one rotor component proximate a stator that is axially displaceable from the stator in response to pressure of lubrication oil delivered to its lubrication system has a system for changing axial displacement of each axially displaceable rotor component from the stator to cause a corresponding change in rotor-stator magnetic flux interaction, comprising: a hydraulic pump for generating a flow of lubrication oil; and means for regulating the flow of lubrication oil to the machine to develop a corresponding lubrication oil pressure that controls axial displacement of each axially displaceable rotor component.

Abstract: A pump has a body and a pressurizing barrel. The body has an outlet tube and a magnetic check valve mounted in the outlet tube to prevent a back-flow current from damaging an impeller mounted inside the body. When closed, the magnetic check valve actuates a magnetic switch to signal external devices. The pressurizing barrel has a tank containing liquid for compensating a pressure in the body and a casing. The casing is externally mounted on the pressurizing barrel and defines a notch for receiving a circuit board and has a detachable cap to facilitate maintenance of the circuit board. Accordingly, the pump effectively prevents impeller and motor damage due to the back-flow current. Moreover, the casing facilitates maintenance of the circuit board.

Abstract: A safety device for a vacuum pump, arranged to be associated with a duct putting the interior of the casing of the vacuum pump in communication with the outside environment, The safety device comprises a breakable member (3), which breaks when subjected to a pressure, which is at least equal to a predetermined threshold (pbreak) chosen so that the member breaks in case when an overpressure could damage the pump, and remains unbroken at operating pressures during normal operation of pump.

Abstract: A first tank, a main body of a compressor, an electric motor, and a second tank are combined to form a single assembly. A booster type air compressor as the single assembly including the first tank may be easily carried. The first tank at an inlet side is integrally combined to prevent a pulsation in the supplied compressed air for eliminating the drain contained in the compressed air. The air compressor, thus, is structured to discharge high compressed air from a high-pressure outlet joint formed on the second tank.

Abstract: The disclosure relates to a feed pump for hydraulic media having an input and an output. A pressure-reducing element is connected to the output, at the output of the element the system pressure being present and the output being connected to a consumer, wherein the output is connected to the first input of a pump controller, the second input being connected to the output of the pressure-reducing element, and wherein the pump controller adjusts the feed pump toward maximum delivery if the system pressure is smaller than a minimum pressure or if the system pressure is smaller than the feed pressure, and wherein parallel to the pump controller a pressure limiter is switched such that at the first input thereof the feed pressure is present and at the control input the system pressure is present, wherein the pressure limiter opens if the feed pressure is greater than a desired quantity.

Abstract: Apparatus is described for inhibiting the propagation of a flame front ignited by a pumping mechanism drawing a waste stream from a process chamber. A combustion chamber comprises an inlet for receiving the waste stream exhaust from the pumping mechanism and means for generating a flame for burning a flammable component of the waste stream. A pressure detector detects a pressure at a location through which the waste stream is drawn by the pumping mechanism, and a flame detector detects the presence of a flame in th combustion chamber. A controller regulates the delivery of at least one process fluid to the process chamber if the detected pressure is greater than a pressure above which the flame front can be sustained by the waste stream, or if there is no flame present in the combustion chamber.

Abstract: The invention relates to a fuel metering unit, in which the displaceable parts of an electromagnet are guided through two bushings in an axial direction, the bushings being located at a distance from one another. The bushings guide the armature bolt, which can be produced from a wear-resistant material, such as for example tempered steel.

Abstract: A feedback control loop for a high pressure pump modifies the accumulator velocity and pressure during solvent transfer. The accumulator velocity is adjusted to maintain the system pressure equal to the expected pressure to thereby eliminate the effect of the flow deficit created by a thermal effect.

Abstract: A surge anticipator safety check unit for use in a liquid system for preventing damage to a pump and associated components of the system in the event of a loss in pumping pressure is provided. The unit includes a surge anticipator portion having a surge anticipator valve assembly, a hydraulic or electronic controller for operating the surge anticipator valve assembly depending on the conditions in the liquid distribution system, and a sensor associated with the controller for sensing the conditions in the downstream portion of the piping relative to the safety check unit. The surge anticipator safety check unit operates in conjunction with the operation of a check valve member in the piping and an air vacuum portion and operates to eliminate or minimize surge in the system. The valve assembly includes a solenoid plunger connected to a valve member. The plunger is operated by the controller for opening and closing the surge anticipator portion.

Abstract: A variable displacement compressor is disclosed that draws refrigerant from a suction pressure zone and discharges the refrigerant to a discharge pressure zone, and controls displacement according to a pressure in a control pressure chamber. The compressor has a cam body, pistons, a supply passage, a release passage, and an on-off valve. The inclination angle of the cam body is changeable based on the pressure in the control pressure chamber. A piston reciprocates in each cylinder bore as the cam body rotates. The supply passage supplies the refrigerant in the discharge pressure zone to the control pressure chamber. The release passage releases the refrigerant in the control pressure chamber to the suction pressure zone. The on-off valve selectively opens and closes the release passage in response to changes of the temperature. The on-off valve shuts off the release passage when the temperature is equal to or higher than a predetermined temperature.

Abstract: A multi-stage rotary compressor to reduce a driving load and prevent a malfunction due to an abrupt pressure rising. In the compressor of the type including first and second compressing units mounted in a hermetic casing thereof to compress a gas, the gas being primarily compressed in the first compressing unit and secondarily compressed in the second compressing unit, the interior of the hermetic casing is divided into a plurality of spaces including first and second pressure chambers. The first pressure chamber surrounds the first compressing unit and is kept at a discharge pressure of the first compressing unit, and the second pressure chamber surrounds the second compressing unit and is kept at a discharge pressure of the second compressing unit.

Abstract: An oil pump includes: a rotor 3 for actuating a pump action to suck oil in a suction passage 24 from a suction port 27 to supply oil to a delivery passage by way of a delivery port 19; and a flow control valve for returning an excessive oil from the delivery passage to the suction passage 24 as a returning flow of oil by way of a bypass passage 29 when a flow amount of oil is excessive in the delivery passage. A corrosion-proof member 9 having corrosion resistance is disposed at the position which faces to the returning flow of oil in the inner wall surface of at least one of the suction passage 24 and the bypass passage 29. The corrosion-proof member 9 has a discontinuous shape (for example a V-shape or a U-shape) in a circumferrencial direction of center line P1 in a cross section which intersects the center line P1 at right angles.

Abstract: A pumping system including a fluid inlet line and a primary pump for the fluid. The primary pump includes an impeller in an impeller chamber, with the impeller chamber adapted to receive fluid from the inlet line. A suction chamber is above the impeller chamber, with a throttle opening between the impeller chamber and the suction chamber. A priming pump is adapted to draw fluid through the throttle opening into the suction chamber. A fluid path is provided around the impeller chamber and between the inlet line and the suction chamber, with the fluid path having a larger area than the throttle opening and including a float restrictor.

Abstract: Pump pressure output can be controlled as temperature changes by a temperature compensation element. The present invention provides a shear channel constructed out of two or more materials enabling a pump to have a pressure profile as a function of temperature for a viscous fluid. The channel height varies as a function of temperature when the channel walls and temperature compensation element are constructed from materials having different coefficients of thermal expansion. By selecting a combination of materials, the channel height can increase, decrease, or remain constant as the temperature is changed. Ignoring the effects of viscosity, channel length, and relative speed the effect of channel height on pump output pressure is assessed: by increasing channel height as temperature increases, the pressure will decrease; by keeping the channel height constant as temperature increases, the pressure will remain constant; and by decreasing channel height as temperature increases, the pressure will increase.

Abstract: Apparatus and method for aspirating liquid from a container, e.g., a test tube or other vessel, includes apparatus for sensing that an aspiration probe tip is contacting the inside bottom wall of the container, whereby a maximum volume of liquid can be aspirated from the container. According to the invention, an encoder is mounted on the driven member of a motor (e.g., on a rotatably-driven drive shaft or a nut of a stepper or D.C. motor, or on a linearly-driven shaft of a linear actuator) used to rectilinearly advance the probe tip into the container. Such encoder produces a series of pulses indicating the speed and/or linear position of the probe tip. A motor controller responds to a predetermined change in pattern of pulses from the encoder indicating that movement of the probe tip has been resisted by the vessel bottom, whereby further movement of the driven member and of the probe connected thereto is arrested, and the probe tip remains in contact with the vessel bottom.

Abstract: A variable capacity rotary compressor includes a housing having a compressing chamber, a roller to rotate in the compressing chamber while coming into contact with an inner peripheral surface of the compressing chamber, a vane to move forward and rearward along a guiding groove in accordance with rotation of the roller, the guiding groove being formed in the housing in a radial direction of the compressing chamber, a vane control device to regulate restriction and release of the vane as to whether or not the vane comes into continuous contact with an outer peripheral surface of the roller, and a controller to output a control signal to the vane control device for the variation of a compression capacity, so as to regulate a proportion of restriction and release of the vane, and a capacity variation method using the variable capacity rotary compressor.

Abstract: An inventive method of preventing unpowered reverse rotation in a compressor includes the steps of placing a solenoid valve at a location near compressor discharge. The valve is preferably actuated soon after the power to the motor is cut off, blocking the flow of refrigerant from expanding back toward the compression chambers of the compressor. The compressor is disclosed as a scroll compressor, but may also be a screw compressor. These two types of compressors are susceptible to undesirable unpowered reverse rotation when compressed refrigerant re-expands through the compression elements from the compressor discharge into the compressor suction. By blocking the flow of refrigerant, this unpowered reverse rotation is prevented. A high pressure switch can be positioned directly upstream of the solenoid valve to immediately stop the compressor if the valve malfunctions and blocks the flow of refrigerant during normal compressor operation.

Abstract: A diaphragm metering pump suitable for metering an effervescent gas. The pump has a pump head with a product chamber having an inlet end with a one-way inlet valve and an outlet end with a one-way outlet valve. A displaceable diaphragm member defines a boundary of the product chamber. The diaphragm member is capable of being reciprocated to cause pumping displacements. A discharge side is disposed downstream from the outlet valve. A passageway is disposed in fluid communication between the discharge side and the product chamber. A valve is disposed in the passageway. The valve is opened intermittently to allow liquid to re-enter the product chamber in an amount effective to purge gas from the product chamber to prevent loss of prime.

Abstract: The invention relates to a reverse rotation preventing structure of a centrifugal compressor. The reverse rotation preventing structure of the centrifugal compressor comprises: a discharge pipeline of the centrifugal compressor; a suction pipeline of the centrifugal compressor; a bypass pipeline for connecting the discharge pipeline and the suction pipeline, wherein a predetermined valve is formed thereon; a control means for controlling an operation of the centrifugal compressor; and a detecting means for generating a predetermined signal to the control means if the operation of the centrifugal compressor is suddenly stopped, thereby opening the bypass pipeline.

Abstract: A fuel injection control unit, including an electronic governor and a controller for an engine performs control in a governor region based on an isochronous characteristic. A working machine controller receives a delivery pressure signal P and controls a regulator such that, when the delivery pressure of a hydraulic pump exceeds a predetermined pressure P1, the displacement of the hydraulic pump does not exceed a value decided in accordance with a preset pump absorption torque curve. The working machine controller controls the regulator such that, when the delivery pressure of the hydraulic pump 2 is not higher than the predetermined pressure P1, the displacement of the hydraulic pump is increased as the delivery pressure of the hydraulic pump lowers from the predetermined pressure P1.

Abstract: A novel pump pressure limiting method for preventing coolant in a cooling system from reaching pressures that exceed predetermined system coolant pressure limits. The method includes reducing the system coolant pressure, as needed to prevent system over-pressurization, by reducing the operational speed of a coolant pump used to pump the coolant through the system. In one embodiment, the system coolant pressure is determined directly, by measurement of the pressure of the coolant in the system typically using pressure sensors. The operational speed of the coolant pump is then reduced until the system coolant pressure decreases to within the predetermined pressure limits. In another embodiment, the system pressure is determined indirectly, by obtaining pressure-indicating data such as coolant temperature. The coolant system pressure is then correlated with the coolant temperature or other data and then the operational speed of the coolant pump is reduced accordingly.

Abstract: An oil pump unit includes an additional outlet port connected to the downstream side of the pump through the pump cover. With this additional port, the oil pump unit is able to have electronic vacuum and pressure sensors upstream and downstream of the pump for remote monitoring of the pump. The invention is particularly suited for oil pump units which have a main discharge outlet port through the one side of the pump body and a main inlet port through an opposing side of the pump cover. The invention is also particularly suited for oil pump units having a solenoid valve mounted at the top side of the pump body which prevents installation of a pressure sensor along the top side.

Abstract: The invention describes a displacement unit (1) for example for supply, manipulation, guiding or control systems of mounting parts (2), with components (3, 4) that can be adjusted relative to one another by means of a drive unit (5) and with at least one guiding device (6) for at least one of the components (3; 4) and a control unit (7). At least one member (8) of the control unit (7) used for processing logic information or bus information is integrated into the drive unit (5) and/or into at least one of the components (3; 4) and/or is mounted on one of the components (3; 4).

Abstract: A hydraulic pump is provided that includes a housing having a fluid inlet and a fluid outlet. A pumping element is operable to increase the pressure of fluid received through the fluid inlet and to generate a flow of pressurized fluid through the fluid outlet. A control device is operatively engaged with the pumping element to control the flow rate of the flow of pressurized fluid generated by the pumping element. A fluid passageway connects the control device with the fluid outlet. A valve is disposed in the fluid passageway between the fluid outlet and the control valve. The valve is moveable between a first position where the valve blocks a flow of fluid relative to the fluid passageway and a second position where a flow of fluid is allowed to flow through the fluid passageway.

Abstract: A workbench for an air compressor that includes a work surface as its top surface. The workbench is provided on wheels, such as caster wheels. The workbench may be closed by panels to attenuate sound. The panels may be removable to provide access to the compressor for maintenance or repair. A mechanism may be provided whereby a drain for the air compressor may be remotely actuated so that the compressor tank may be drained without opening the panels or having to reach under the workbench. The power feed to the motor may be used to power an outlet on the workbench when the motor is not running. The outlet may be provided on the outer shell of the workbench (e.g., on a panel on the outside of the workbench). A switch may be provided that routes the power to the outlet instead of the motor.

Abstract: A fuel injection system in which, by means of a controlled zero-feed throttle or by the elimination of the zero-feed throttle and by a suitable control of the pressure valve of a common rail, the starting performance of the internal combustion engine can be improved, and at the same time it is assured that in the overrunning mode of the engine, an excessively high pressure is not built up in the common rail.

Abstract: Fluid pump for medicinal, especially endoscopic, applications having a transport channel led through a drive, a device possessing a measuring chamber for measuring the pressure of the fluid conveyed in the transport channel and control means for the automatic control of the behaviour of the pump, in particular its transport behaviour, as a function of the measured pressure and as a function of a code value contained in code value carrier means which are provided on or in the measuring chamber, wherein the code value is detected during and/or after fixing of the measuring chamber on the pump housing by read-out means in the fluid pump.

Abstract: A vane pump is disclosed for use with gas turbine engines that is adapted and configured to provide a failure mode similar to that of a traditional gear pump. The vane pump includes a pump housing, a cam member, a cylindrical rotor member and a mechanism for communicating a high pressure fluid from the discharge arc region to the inlet arc region when the tip surface of each vane element has experienced a predetermined amounted of wear so as to prevent pump startup. The tip surface of each vane element wears as a result the sliding contact with the circumferential surface of the pumping cavity.

Abstract: A hydraulic pump is provided that includes a housing having a fluid inlet and a fluid outlet. A pumping element is operable to increase the pressure of fluid received through the fluid inlet and to generate a flow of pressurized fluid through the fluid outlet. A control device is operatively engaged with the pumping element to control the flow rate of the flow of pressurized fluid generated by the pumping element. A fluid passageway connects the control device with the fluid outlet. A valve is disposed in the fluid passageway between the fluid outlet and the control valve. The valve is moveable between a first position where the valve blocks a flow of fluid relative to the fluid passageway and a second position where a flow of fluid is allowed to flow through the fluid passageway.

Abstract: An intracardiac rotary pump (10) is provided with a pressure differential sensor (18) for supporting the pumping heart. The pressure differential sensor measures the pressure differential between aorta (AO) and left ventricle (LV). This pressure differential must correspond to certain desired values at different speed stages. If the pressure differential deviates to too large an extent, the deviation is recognized as a drift of the pressure sensor, and a correction value is determined in dependence on the drift, the subsequently measured pressure values being corrected with the aid of this correction value. In this manner it is possible to carry out a drift correction on the sensor with the pump arranged in the heart and even with the pump in operation.

Abstract: A submersible pump assembly has a pump and a valve connected to the outlet of the pump. An outlet of the valve is connected to a riser. A valve member in the valve housing is vertically movable between a pumping position and a priming position, the valve member being biased toward the priming position. A priming conduit connects the outlet of the valve housing to the inlet of the pump for directing well fluids flowing through the conduit into an intake of the pump for re-priming the pump. When the pump is pumping well fluid, the valve member is moved to the pumping position by the fluid pressure, well fluids flowing from the inlet of the valve housing to the outlet of the valve housing but not through the priming conduit. When pumping ceases, the valve member returns to the priming position, well fluids flowing through the priming conduit for re-priming the pump.

Abstract: A pressure booster and method for amplifying a water pressure that is supplied by a water facility is provided. The pressure booster is configured to be connected between the water facility and one or more semiconductor substrate cleaning systems. The pressure booster includes a pump having a pump input that connects to the water facility and a pump output that is configured to produce a fluctuating amplified water pressure that is greater than the water pressure that is supplied by the water facility. Further included is a pressure dampener having a dampener input for accepting the fluctuating amplified water pressure from the pump output. The pressure dampener is configured to partially reduce pressure fluctuations in the fluctuating amplified water pressure. The pressure dampener also has a dampener output. A pressure regulator having a regulator input for receiving the dampener output is also included as part of the pressure booster.

Abstract: A method and apparatus for converting a pump for use in a flow stream containing a mixture of highly compressed gas, compressible liquid or supercritical fluid wherein the pump delivers a compressible fluid against a back-pressure regulator which in turn delivers a controllable flow rate downstream of the regulator without performing variable compressibility compensation adjustments on the pump. By using a pressurized source of compressible fluid combined with isocratic conditions, the delivery pressure from the pump is controlled at a rate higher than the downstream gradient with the back-pressure regulator, and an inexpensive pump may be used in place of specialized, expensive pumps and compressibility compensation systems for use in stems operating at or near supercritical fluid levels of compressible fluids. Significant capital and operating laboratory costs are saved through a simpler and cheaper system for accurately delivering compressible fluids into mobile phase flow streams.

Abstract: A dispensing system for petrol pumps, comprising a pump, a dispensing valve in a petrol pump nozzle and an electrically controllable solenoid valve (10), characterized in that the solenoid valve (10) includes a directly acting principal valve (18) and a bypass valve (30) arranged so as to bypass the principal valve (18), and a solenoid drive (34) by which in case of a differential pressure present above the sealing seat (24) of the principal valve (18) at first only the bypass valve (30) is able to be switched to the open position, and only after a pressure compensation has, occurred at the sealing seat (24) of the principal valve (18) by the opening of the bypass valve (30) is the principal valve (18) also able to be switched to the open position.

Abstract: In a fuel feed unit (2) a bleed valve (9) is connected to a region which is constantly filled with fuel. This means that gases pass out of the fuel feed unit (2) through the bleed valve (9). However, penetration of gases when the fuel feed unit (2) is not operating, via leaks in the bleed valve (9), is reliably avoided.