Abstract: Provided is a compressor having an enhanced capability of supplying oil to a thrust bearing and a radial bearing which are interposed between a center through-hole in a cylinder block and a driving shaft. To this end, the compressor 1 has an air bleed passage 31 which is configured to allow crank chamber 5 and intake chamber 7 to communicate with each other, including: a first space S1 in the center through-hole 14; a communicating part 41 for allowing the first space S1 and a second space S2 to communicate with each other; the second space S2 in the center through-hole 14; a penetrating passage 43 formed to pass through the driving shaft 10, thereby allowing the second space S2 and a third space S3 to communicate with each other; the third space S3; and a communicating passage 45 for allowing the third space S3 and an intake chamber 7 to communicate with each other.

Abstract: In a piston-type compressor in which a working fluid is taken in through an intake port is first compressed with pistons and is then let out through an outlet port, an axial hole ranging along the axial direction and a radial hole communicating with the axial hole and opening into a crankcase are formed within the shaft. Additionally, a first intake passage through which the working fluid having flowed in through the intake port is guided via the crankcase to the radial hole and the axial hole and a second intake passage through which the working fluid having flowed in through the intake port is guided to join the working fluid having been drawn into the first intake passage by bypassing the crankcase are formed in the compressor. The working fluid is taken into cylinders from the area where the first working fluid and the second working fluid join each other.

Abstract: In a hydraulic apparatus, a first rotating member and a second rotating member are provided so as to be relatively rotatable with a same central axis, a cam is provided on the first rotating member, pistons are arranged on the second rotating member so as to be opposed to the cam, the pistons are pressed against the cam to contact by compression coil springs, oil chambers of which volumes are expanded and contracted according to movements of the pistons are provided on the second rotating member, first and second fluid paths through which oil flows into and out from the oil chambers are provided, and a path switching device for switching an inflow direction and an outflow direction of the oil in the first and second fluid paths according to difference in pressure between the first and second fluid paths is provided.

Abstract: The power conversion mechanism of a variable displacement reciprocating compressor includes a joint shaft (54) that is fitted to a drive shaft (30) through a bearing (56) and supported by an inner circumferential face of a support hole (58) formed in the cylinder block (20) so as not to be relatively rotatable but to be slidable relative to the inner circumferential face; a joint case (66) that is integrally and tiltably formed in the conversion mechanism (38); and a plurality of balls (74) rollably held between JS-side protrusions that are integrally formed in the joint shaft (54) and JC-side protrusions (62) that are integrally formed in the join case (66). The variable suction throttle mechanism of the compressor uses the sliding movement of the joint shaft (54) to change air-flow resistance in a valve chamber (101) communicating with the support hole (58).

Abstract: A suction throttle valve of a compressor has a compressor housing having a suction chamber and a crank chamber. The suction throttle valve includes a suction passage formed in the housing, a suction port provided at an inlet of the suction passage, a valve body movably arranged in the suction passage for adjusting opening of the suction passage, an urging member for urging the valve body toward the suction port, and a valve chamber provided in the suction passage. Refrigerant is drawn into the suction passage through the suction port and then received in the suction chamber. A first communication hole is formed through the housing, through which the valve chamber and the suction chamber are in constant communication with each other. A second communication hole is formed through the housing, through which the valve chamber and the crank chamber are in constant communication with each other.

Abstract: A variable flow pump includes: a housing with inlet and outlet chambers interconnected by a main bore and a non-rotating cylinder block positioned in the main bore. The cylinder block includes: a central bore communicating with the inlet chamber; cylinder bores arrayed around the central bore; first feed passages interconnecting the inlet chamber and the cylinder bores, defining a bypass flowpath between the cylinder bores; and at least one discharge valve disposed at the second end which permits fluid flow from the cylinder bores to the discharge chamber but prevents opposite flow; Pistons are disposed in the bores. A shaft is coupled to the pistons so as to cause them to reciprocate through an axial pump stroke when the shaft is rotated. A mechanism is coupled to the cylinder block which modulates the axial position of the cylinder block within the housing, varying the size of the bypass flowpath.

Abstract: A variable displacement compressor includes a housing assembly. A displacement control structure for the variable displacement compressor includes a passage forming member, a flat partition and a displacement control valve. The passage forming member is connected to an exterior surface of the housing assembly for forming a refrigerant passage for allowing the refrigerant to be discharged out from the compressor to an external refrigerant circuit. The flat partition is interposed between the passage forming member and the housing assembly. A throttle penetrates through the partition, which divides the refrigerant passage into an upstream passage and a downstream passage. The displacement control valve is provided in the passage forming member. The displacement control valve senses pressure of refrigerant in the upstream passage and pressure of the refrigerant in the downstream passage to control flow rate of the refrigerant flowing through a supply passage.

Abstract: A displacer unit with a valve plate body is disclosed. The displacer unit having at least one displacer space which is arranged in a cylindrical drum rotating about an axis of rotation and which can be connected to an inlet connection and an outlet connection by a control surface. The control surface is formed on a valve plate body which is provided with a first control opening, which is connected to the inlet connection, and with a second control opening, which is connected to the outlet connection. The first control opening and the second control opening are spaced apart radially, where the displacer space can be connected to the first control opening by a first connecting passage and to the second control opening by a second connecting passage. The connecting passages are provided with a respective mechanical face seal for sealing relative to the control openings.

Abstract: In a piston valve in a compressing pump, a discharge base formed in the center of the piston valve has a planar shape having discharge spouts formed corresponding with each inlet slots. A 3-bladed anti-backflow plastic gasket covers the top of the discharge base such that each blade can block corresponding discharge spouts. As wobble wheels of the compressing pump push the diaphragm in turns, the water flow from each said inlet slot at each area will continuously run into each discharge spout at each area in said discharge base in turn so that each blade of the gasket moves up and down in turn as well, to achieve an open-and-shut effect of the discharge spouts. Therefore, drawbacks of leakage, pressure loss, or failure can be prevented, and the serving life of the gasket can be prolonged, improving the compressing and discharging efficiency of the pump.

Abstract: A fuel control system is provided in a single compact modular unit. The unit includes a motor driving a highly accurate cam-operated double-acting piston metering pump, both of which are contained in a liquid fuel environment. As the liquid fuel is pumped it works to cool internal components including the motor. An electronic motor drive is contained in a dry chamber of the unit for controlling operation of the motor and pump and is cooled indirectly by the fuel as well. A pressure sensitive flow divider is also included for selectively providing one or multiple output fuel flow paths depending upon whether a pressure threshold is reached, for example to send fuel to primary and secondary burner nozzles. Filter, filter bypass, pressure relief, and fuel shut-off components are also integrated into the single modular unit.

Abstract: A hydraulic motor includes a rotor supporting a plurality of piston elements projecting away from opposing faces of the rotor. The rotor is adapted to rotate about a first axis. The hydraulic motor further includes a pair of drum plates each supporting a plurality of cup elements. The plurality of cup elements are adapted to engage the piston elements. Each drum plate is arranged on an opposing side of the rotor and is adapted to rotate about a second axis in angled relation to the first axis. Each of a pair of swashplates is in operative engagement with a respective one of the drum plates and each is adapted to pivot relative to the rotor to move with the respective drum plate between a maximum displacement position and a minimum displacement position to thereby change the angled relation between the first axis and the second axis. The pair of swashplates are further independently pivotable between three different settings.

Abstract: A fluid metering device for monitoring flow of fluid is provided. The fluid metering device comprises: an electric motor; and a housing having a manifold section, a motor adapter plate and a pressure retaining container, said pressure retaining container encompassing a pressurized chamber having a hydraulic pump placed in the pressurized chamber; and the manifold section including an air bleed valve and a pressure biased relief valve for maintaining pressure within the housing.

Abstract: Pump apparatus and method. The pump can include a valve assembly and a diaphragm. In some embodiments, the diaphragm can include a convolute that can deform in order to increase a volume of a pumping chamber to provide an internal fluid bypass when a pressure in the pumping chamber exceeds a bypass pressure. In some embodiments, the pump can include a fluid reservoir at least partially defined by a wall with a flow-restrictive conduit in fluid communication with an outlet chamber. A shut-off switch can include an actuator in fluid communication with the fluid reservoir. The fluid reservoir and the flow-restrictive conduit can substantially isolate the shut-off switch from pressure pulses in the outlet chamber.

Abstract: This invention is a pressure control valve unit including: a unit substrate; a first valve chamber provided at one side of the unit substrate, forming a part of a first liquid flow-path; a second valve chamber provided at the other side of the unit substrate, forming a part of a second liquid flow-path; a first opening-closing valve provided in the first valve chamber; and a second opening-closing valve provided in the second valve chamber. The first liquid flow-path and the second liquid flow-path are formed independently of each other. A pressure of a liquid flowing in the first liquid flow-path and a pressure of a liquid flowing in the second liquid flow-path can be controlled at respective predetermined pressures independently of each other.

Abstract: A double-headed piston type compressor forms a first compression chamber and a second compression chamber for compressing gas. The compressor has rotary shaft having an inner chamber that interconnects a suction chamber and the first and second compression chambers for introducing the gas into the first and second compression chambers. The compressor also has a partition wall that is located in the inner chamber for dividing the inner chamber into a first passage and a second passage. The first passage interconnects the suction chamber and the first compression chamber. The second passage interconnects the suction chamber and the second compression chamber.

Abstract: The reciprocating pump for performing a pumping action by reciprocating an individual reciprocating member inside a plurality of cylinder sections arranged in parallel includes a seal case in which a cylinder section is formed and which functions as an independent pressure-resistant container; and a suction valve and a discharge valve in which a valve chamber is formed individually and each of which functions as an independent pressure-resistant container. The suction valve and the discharge valve are coupled so as to sandwich two planar sections from a direction perpendicular to a direction in which a plurality of cylinder sections are arranged in parallel in a state in which each of the suction valve and the discharge valve abuts against the respective one of the two planar sections of an external surface of a small diameter section at a front end side formed in the seal case, and the valve chamber is communicatively connected to the cylinder section.

Abstract: [Problems] A control valve for a variable displacement compressor, where sliding resistance by movement of a valve is reduced as much as possible to stably and accurately regulate the rate of air flow, enabling a suction pressure corresponding to solenoid thrust to be maintained. [Means for Solving Problems] The discharge pressure Pd of the compressor introduced into a pressure sensing section (40) applies urging force to a movement member (50), and a solenoid section (36) applies, in cooperation with the urging force, urging force to the movement member (50) depending on an input signal. The degree of opening of a valve body (56) provided at the movement member (50) is set according to the position of the movement member (50) to regulate the rate of air flow in a communication path for interconnecting a discharge pressure region of the compressor and a compressor inner chamber.

Abstract: A high purity, high precision pump capable of pumping more than one type of chemistry or process fluid without requiring cleaning or changing of surfaces contacting the processing fluid. The pump employs a single drive mechanism coupled in parallel with multiple pumping chambers, each capable of handling a different type of manufacturing fluid. The pump can be utilized as part of a single stage or multi-stage pump system.

Abstract: A pump having an endplate with an orifice provided between the system ports and the charge pump pressure cavity. Fluid flows through the orifice so as to soften a transition of the vehicle from a stationary position to a forward or reverse motion when a swash plate of the pump is angled slightly relative to a neutral or zero position.

Abstract: A swash plate compressor (41) is disclosed, wherein a shaft (43) is divided into a rear shaft (45) and a front shaft (47) coupled to each other through a torque limiter (65) with center holes (51, 69) communicating with each other. A lug plate (25) is fixed to the rear shaft (45). Machining of the center holes is thus facilitated while at the same time eliminating the need for rust-proofing of the torque limiter.

Abstract: To provide a control valve which is capable of maintaining the minimum operation of a variable displacement compressor, by causing a valve section thereof to be fully opened, irrespective of the expanded or compressed state of a bellows, even when the suction pressure of the compressor is high. In the control valve for a variable displacement compressor, a bellows is disposed between a pressure-sensing piston and a core in a pressure-sensing chamber, and a pressing force-transmitting member which is fixed to a plunger is interposed between the pressure-sensing piston and the bellows. Then, a spring which urges the pressing force-transmitting member toward a valve section is disposed between the pressing force-transmitting member and the bellows.

Abstract: Compressor, especially a compressor for the air-conditioning system of a motor vehicle, having a housing (1) and, for drawing in and compressing a coolant, a compressor unit arranged in the housing (1) and driven by means of a drive shaft, the compressor unit being regulated by means of the pressure (PC) prevailing in a drive mechanism chamber substantially bounded by the housing (1), there being an additional regulation device (17) and/or control device for the inlet-gas-side coolant mass flow and/or the inlet pressure and/or the inlet density.

Abstract: A rotary valve for switching supply passages, and discharge passages of high-temperature and high-pressure steam for a rotor rotatably supported at a casing is constructed by making a fixed side valve plate and a movable side valve plate abut to each other on a slide surface. A pressure chamber into which the high-temperature and high-pressure steam is introduced from the supply passage is opened to a mating surface of a valve body portion with the fixed side valve plate. The fixed side valve plate supported to float is pressed against the movable side valve plate with a pressing load generating in the pressure chamber to bring it into close contact with the slide surface. Leakage of the high-temperature and high-pressure steam from the pressure chamber is prevented by placing a V-packing inside the pressure chamber.

Abstract: The invention provides a compressor with a shut off valve disposed between the crank case and the suction cavity. The valve is moveable between an open and closed position in response to the pressure in the discharge cavity of the compressor. The valve is an on/off valve and is operable rapidly depressurize the interior of the crank case when the compressor transitions from a minimum stroke. The valve can define first and second fluid pathways. The first fluid pathway can be larger than the second fluid pathway and be selectively opened and closed. The second fluid pathway can be permanently open and act as a bleed between the crank case and the suction cavity.

Abstract: A dual pump apparatus for use on a vehicle or industrial application having a housing in which a pair of hydraulic pumps are mounted, having a cooling fan mounted on the primary or secondary input shaft on the opposite side of the pulley used to engage the prime mover. A charge pump may be mounted on the end cap, and the trunnion arms for controlling the hydraulic pumps extend out of opposite sides of the housing. An auxiliary pump may also be mounted on the primary input shaft and may be located either at the input end thereof adjacent to the pulley, or on the opposite side of the housing.

Abstract: A two-stage pressure relief valve for use with hydraulic systems is disclosed. The two-stage pressure relief valve has a first stage that relieves increases in hydraulic system pressure over the normal operating pressure and up to a selected threshold pressure level, and a second stage that brings the hydraulic system pressure down to a selected reduced operating pressure that is below the normal operating pressure in response to increases in the operating pressure over the threshold pressure level.

Abstract: The object is to provide a capacity control valve for a variable displacement compressor, which is not adversely affected by pressure from a pressure-regulating chamber. The cross-sectional area of a valve hole of a high pressure-side valve seat for introducing discharge pressure Pd of a variable displacement compressor into a pressure-regulating chamber is A, the cross-sectional area of a valve hole of a low pressure-side valve seat for introducing pressure Pc1 (=Pc2) of the pressure-regulating chamber into a suction chamber is B, and the average cross-sectional area of a refrigerant passage assumed when a low-pressure valve element is open during most of control time of actual operation is b. A and B are set to A<B to make the effective pressure receiving area (?A) of the high pressure-side valve and the effective pressure receiving area (?B?b) of the low pressure-side valve approximately equal.

Abstract: Pump or motor having a rotor with chambers with a through rotation variable volume which are connectable via switches to either a first line connection or a second line connection. During switching between the line connections, the volume of the chamber changes and to avoid pressure peaks or cavitation the chambers are interconnected with connecting lines. Each connecting line has closures to stop the flow through the connecting line after a limited volume of fluid has passed in one direction.

Abstract: This invention relates to a pumping system. The design of the system is such that bi-directional operation can be achieved using a significantly smaller and hence lighter unit than those currently available. It uses the direction of rotation of the drive shaft to control the opening and closure of the by-pass means for controllably returning the fluid to the first reservoir.

Abstract: A control system for a variable displacement compressor uses a mechanical valve to minimize energy consumption in an air conditioning system. The control system can also provide instantaneous indications to the vehicle controller of air conditioning power consumption to avoid engine loading. Controls are also used to contain oil within the compressor and to minimize its presence downstream of the compressor into the gas cooler and evaporator parts of the system.

Abstract: An oil pressure operated pump for marine steering gears includes a multiple piston oil pressure operated pump controlled by a steering wheel, a valve housing mounted under the pump, a bottom cover closing the valve, the valve housing and the cover each including channels, threaded holes for reciprocal fastening thereof, non-threaded bores for oil pressure connections, a valve set lodged in the valve housing for non-return and adjustment of oil flow, the valve set including a generally parallelepiped shaped tubular shell having a generally external square shape, a central tubular through-hole, and lathe-turned ducts, a double acting oil pressure cylinder including a shaft movable in the central tubular through-hole for controlling a direction of an engine or rudder of a boat, and valves for controlling fluid flow and thereby movement of the shaft.

Abstract: The invention relates to an axial piston drive with a continuously adjustable piston stroke, which comprises a drive shaft (10, 12) on which a swash plate (16) is supported in a crank chamber (14) in such a way as to be tiltable and displaceable in the axial direction, as well as a controller (18, 20) by means of which an tilt angle and an axial position of the swash plate (16) can be adjusted, and at least one piston (26, 28) connected to the swash plate (16) so that it can be actuated to move within a cylinder (22, 24).

Abstract: Variable displacement pump pumps oil to one or the other ports of an oil operated vehicle wheel motor to drive a lawn mower.

Abstract: A piston pump including an inlet manifold, and outlet manifold, and a piston ring sandwiched between the inlet and outlet manifolds. The inlet manifold has a first face and a second face with at least one outlet formed in the second face. The outlet manifold has a first face and a second face, and includes at least one inlet formed in the outlet manifold first face. The piston ring has an inlet face and an exhaust face, wherein the piston ring is sandwiched between said inlet manifold second face and said outlet manifold first face, and has at least one radially extending cylinder formed therein. The piston ring further includes an inlet passageway formed in the piston ring between the inlet face and the cylinder and in fluid communication with the inlet manifold. The piston ring also has an exhaust passageway formed therein between said cylinder and the exhaust face and in fluid communication with the outlet manifold inlet.

Abstract: A hydraulic system, such as a fuel injection system, includes a fixed displacement pump with at least one pump piston. A sleeve surrounds each pump piston and provides the method by which fluid displaced by the pumping stroke of the pump piston is directed either to a high pressure area in the pump or a low pressure area. The sleeves are a portion of an electro-hydraulic controller that includes a mechanical bias to bias the pump to a high output position when a pressure differential between the outlet area and the inlet area is relatively low, such as at cold start up. This aspect facilitates priming of the system. In addition, the controller includes a biasing hydraulic surface in opposition to the mechanical biaser that serves to bias the pump to its low output position when the pressure differential between the outlet area and the inlet area is relatively high. This aspect prevents over pressurization in the event that electric current to the controller is disrupted.

Abstract: The invention relates to a hydraulic device provided with a housing having at least a first line connection and a second line connection and, if appropriate, further line connections, a rotor which can rotate in the housing and chambers which are alternately connected to one of the line connections as a result of the rotation of the rotor. According to the invention, chambers are connected by connecting lines in which there are means for closing a connecting line after a limited volume of fluid has flowed through the connecting line in one direction.

Abstract: A pump includes a stationary pump housing having a central longitudinal axis and a housing chamber, a rotating pump shaft extending through the pump housing and into the housing chamber, a rotating barrel fixed to the pump shaft and including a plurality of pump chambers, and a plurality of rotating and reciprocating pump pistons. Each pump piston is at least partially contained within a respective pump chamber. A fluid delivery control assembly is provided to selectively vary the amount of fluid delivered by the pump. At least one pressurized fluid pool is located between a portion of the rotating barrel and a portion of the pump housing. The pressurized fluid pool may be located along an end surface of the rotating barrel and/or along a side of the rotating barrel.

Abstract: A pump includes a pump housing, a rotating shaft extending through the pump housing, a plurality of pistons, and a plurality of control sleeves. Each piston may be at least partially, slidably contained within a respective piston sleeve. The pistons may also be be operably coupled to the rotating shaft such that rotation of the shaft rotates and reciprocates the pistons. Each control sleeve may be slidably disposed on a respective one of said piston sleeves and operable to selectively vary the amount of fluid delivered by the pump.

Abstract: A pump includes a stationary pump housing having a central longitudinal axis and a housing chamber, a rotating pump shaft extending through the pump housing and into the housing chamber, a rotating barrel fixed to the pump shaft and including a plurality of pump chambers, and a plurality of rotating and reciprocating pump pistons. Each pump piston is at least partially contained within a respective pump chamber. A fluid delivery control assembly is provided to selectively vary the amount of fluid delivered by the pump. At least one pressurized fluid pool is located between a portion of the rotating barrel and a portion of the pump housing. The pressurized fluid pool may be located along an end surface of the rotating barrel and/or along a side of the rotating barrel.

Abstract: A hydrostatic axial piston machine has a drum-like cylinder block which is supported in a manner fixed against rotation on a driving or output shaft and is provided concentrically and parallel to its center line with cylinder boreholes in which axially displaccable pistons are arranged which are supported via spherical heads on a slanting disk which is fixed to the housing and preferably adjustable in its slanting angle. The cylinder openings opposite the slanting disk sweep over roughly kidney-shaped low pressure and high pressure control openings of a control body, between which reversing regions with additional boreholes are located. To control the additional boreholes, which influence the pressure increase or the pressure drop on the passing of the cylinder openings over the reversing regions, in dependence on the operating states, a borehole opens at least in a reversing region of the control body which is connected to the high pressure side or the high pressure control opening by a line.

Abstract: A seal is provided between the housing assembly of a variable displacement compressor and a rotary shaft to seal inside the housing assembly. The seal is retained in a retaining chamber, which is separated from a suction chamber and a control pressure chamber. A refrigerant passage is connected to the retaining chamber to feed a refrigerant to the retaining chamber to cause the refrigerant to contact the seal. The refrigerant passage includes a path extending from outside the housing assembly to the suction chamber through the retaining chamber. A restriction ring having a restriction function guides the refrigerant from the control pressure chamber to the retaining chamber and releases an internal pressure of the control pressure chamber.

Abstract: It is desirable to deliver only the fluid that is used to do useful work and not waste energy. In the subject arrangement, selected ones of a plurality of pistons are held at their top dead center positions when delivery therefrom is not needed. This is accomplished by having a valving arrangement disposed between the associated pressure chambers and first and second inlet/outlet ports. The valving arrangement is movable from a neutral, flow blocking position to an operative flow passing position. At the flow blocking position, fluid flow into and out of the associated pressure chamber is blocked, thus the associated piston is maintained at the top dead center position. By holding selected ones of the pistons at the top dead center position, the effective volume of fluid being used is reduced and energy is saved due to the fact that the selected pistons are not moving any fluid.

Abstract: A variable displacement type compressor has a tiltable swash plate and pistons in cylinder bores. The displacement of the compressor is controlled by changing an inclination angle of the swash plate. A first valve is arranged to open and close the suction passage in response to the pressure in the discharge chamber. The valve element of the first valve is arranged to face the end of the suction passage, and can hermetically close the suction passage when the refrigerant gas is introduced into the pressure chamber from the discharge chamber. The refrigerant gas can be also introduced into the crank chamber when the refrigerant gas is introduced from the discharge chamber into the pressure chamber.

Abstract: Compressor has a driving unit. The driving unit is provided within a crank chamber and decreases the discharge capacity when a control valve opens a control passage to increase the pressure within the crank chamber. The throttle passage delivers oil with the compressed refrigerant to the crank chamber regardless of whether the control valve has opened or closed the control passage. Because the throttle passage may continuously deliver the oil to the crank chamber even when the control valve closes the control passage, the mechanical elements within the crank chamber can be reliably and sufficiently lubricated and the crank chamber is prevented from being in an insufficiently lubricated state.

Abstract: A multistage piston compressor includes a case and a suction chamber and a discharge chamber provided in the case. A rotary shaft is supported in the case. A valve plate provided in the case includes suction ports and discharge ports. A plurality of bores are provided at predetermined intervals about the axis of the shaft. Pistons are housed in the bores and compress refrigerant by reciprocating in accordance with the rotation of the shaft. An intermediate chamber connects a discharge port with a suction port. The refrigerant is compressed in stages by passing through a plurality of bores via the intermediate chamber. Compression chambers are defined between the pistons and the valve plate. A communication passage is provided for setting the pressures acting on the rear faces of the pistons to an intermediate pressure between the suction pressure and the discharge pressure.

Abstract: A variable displacement compressor is operated efficiently by avoiding inefficient conditions. The compressor varies its displacement using a control valve for which an external duty control procedure is performed. A target value for controlling the displacement is determined in accordance with the duty ratio Dt of a drive signal sent to the control valve. If the duty ratio Dt is equal to or greater than a predetermined reference value DJ, the displacement is permitted to be varied corresponding to the duty ratio Dt. If the duty ratio Dt is smaller than the reference value DJ, the variable displacement control through the duty control procedure is suspended. In this case, the compressor is operated with a nullified duty ratio (Dt=0), or a minimum displacement.

Abstract: A displacement pump includes a rotatable drive shaft; a low-pressure hydraulic fluid reservoir; at least one piston containing a piston cavity; and a drive plate connected with the drive shaft. The drive plate includes an inlet passage and a fill slot. The fill slot is fluidly connected with the low pressure hydraulic fluid reservoir via the inlet passage. The drive plate is rotatable about the drive shaft such that as the drive plate rotates, the piston cavity is intermittently fluidly connected with the fill slot.

Abstract: An electronic bore pressure optimization mechanism for dynamically varying the cylinder block piston bore pressure profile in a multiple piston hydraulic unit includes a valve means having a variable orifice disposed in the end cap for metering fluid between leading and trailing pistons in a transition region or between a piston in a transition region and a high or low pressure source; and means for generating a control error signal to the valve means so as to adjust the size of the variable orifice based upon the control signal.

Abstract: A swashplate type variable-displacement compressor includes a compressor housing defining therein a crank chamber, a refrigerant suction chamber, a refrigerant discharge chamber, and a low-pressure refrigerant passage connected to an evaporator outlet, and a pressure regulator. The pressure regulator controls the amount of low-pressure refrigerant gas flowing into the refrigerant suction chamber by regulating a differential pressure between the pressure in the refrigerant suction chamber and the pressure in the crank chamber.

Abstract: A control valve for a variable capacity compressor, which comprises a valve housing having a valve port formed between an inlet port and an outlet port, a valve disposed inside the valve housing for controlling the flow rate through the adjustment of opening degree of the valve port, a pressure sensitive bellows for actuating the opening or closing of the valve, and a solenoid magnetization means, wherein the pressure sensitive bellows is incorporated into the plunger of the solenoid magnetization means.