Abstract: The invention relates to a pump, especially a power-assisted steering pump, comprising a current regulating valve, the current regulating valve comprising a hydraulic resistance, such as a main throttle and a regulating piston, whereby the main throttle can optionally be a regulating pin and an annular orifice.

Abstract: A pressure equalization method and system is provided for starting a compressor while maintaining the condenser at a high pressure and includes a valve and a bleed port. The compressor has a compressor inlet for receiving a fluid at a first pressure and a compressor outlet for discharging the fluid at a second pressure, and is operable to compress the fluid from the first pressure to the second pressure. The valve is proximate to and in fluid communication with the compressor outlet and is movable to an open position when the compressor is operating to permit the fluid at the second pressure to flow through the valve and is movable to a closed position when the compressor stops operating to prevent backflow of the fluid at the second pressure through the valve toward the compressor inlet. The bleed port is upstream of the valve and in fluid communication with the compressor inlet to equalize the pressure of the fluid contained in the compressor when the compressor stops operating.

Abstract: A scroll compressor has a biasing chamber which contains a pressurized fluid. The pressurized fluid within the chamber biases the two scroll members together. A valve assembly is in communication with this biasing chamber and releases the pressurized fluid on demand to remove the load, biasing the two scroll members together. When the biasing load is removed, the two scroll members separate, creating a leakage path between discharge and suction to reduce the capacity of the scroll compressor.

Abstract: A diaphragm pump which overcomes the problem of diaphragm failure due to overfill of the oil transfer chamber. An overfill preventive element in the form of a mechanical stop, a fully closed coil spring, or a valve system, or alternatives are provided.

Abstract: Known compressors are matched to a predetermined power range and therefore cannot supply consumers of a closed air supply system as well as an external consumer with an adequate quantity of air. The invention is directed to a method for limiting the power of a multi-stage compressor wherein at least one compressor stage is switched off when a predetermined power limit is reached. In this way, the lowest compressor stage can be so selected that the external consumer obtains an adequate volume flow. The compressor for the method includes a bypass line (22) which bypasses the inlet valve (19) of a low-pressure chamber (11) and thereby connects the low-pressure chamber (11) to its upstream intake space (16). A controllable control valve (23) is disposed in the bypass line (22) and realizes the connection of the low-pressure chamber (11) to the intake space (16) at a predetermined opening pressure.

Abstract: A by-pass device in a variable displacement compressor has a by-pass passage, a valve body and a deformable separator. The by-pass passage interconnects a discharge pressure region with a crank chamber for releasing refrigerant from the discharge pressure region to the crank chamber. The valve body is arranged in the by-pass passage for opening and closing the by-pass passage. The deformable separator separates a back pressure region from the by-pass passage without sliding. The valve body is urged from a side of an opened position where the valve body is spaced from a valve seat toward a side of a closed position where the valve body contacts with the valve seat by pressure applied from the back pressure region to the separator. The valve body is moved from the closed position to the opened position by deforming the deformable separator.

Abstract: A multistage device (1) for delivering moist gases is provided. Said device comprises several delivery pumps (2, 3) each of which having a displacer that oscillates inside a delivery space, and being connected in series via a connection channel (6). The inventive device also comprises a ventilation device (7) which has at least one ventilation channel (8), whereby the ventilation channel (8) opens into a connection channel (6) that interconnects series-connected delivery pumps (2, 3). The inventive device (1) is characterized in that a ventilation valve (9), which can be motor-actuated by a control device, is interconnected inside the ventilation channel (8), and said ventilation valve (9) can be actuated as required by means of the control device and independent of the lift position of the displacers.

Abstract: A pressure-relieving valve is connected to relieve air pressure from an internal diameter of a transmission pump. On startup, pressurized oil is delivered to the torque converter. At engine idle speed, the centrifugal effects on the oil cause any air (which may have leaked into the torque converter during the shut-down time) to accumulate at the center of the converter. Air pressure output from a torque converter escapes between the housing and the transmission pump to which it is connected. The escaped air reaches the internal diameter of the pump and it is prevented from blowing across the face of the pump to the suction side of the pump by a ball and check valve arrangement which delivers the air to a non-fluid internal part of a transmission, thereby avoiding the leakage of this air to the suction side of the pump and the possible loss of pump prime.

Abstract: A pump capable of releasing excessive air is shown to include a hollow base, a cylinder installed on and communicated with the hollow base, a piston movably received in the cylinder, a piston tube including a lower end connected with the piston and an upper end located beyond the cylinder, a tube including a lower end communicated with the hollow base and an upper end inserted into the piston tube through a channel defined in the piston, a release valve mounted on the upper end of the piston tube and a handle mounted on the upper end of the piston tube. The valve is installed on the handle so that it can be touched conveniently and operated easily by a user who is using the pump.

Abstract: An automatic inlet control mechanism and air compressor unit include a valve cavity and valve outlet. The valve cavity includes a valve control chamber and valve inlet chamber. A valve piston assembly is positioned between the valve control chamber and the valve inlet chamber to prevent the flow of air between therebetween. The valve outlet allows air to flow from the valve inlet chamber into the compressor unit. The valve piston assembly prevents air from flowing from the valve inlet chamber to the valve outlet when the compressor unit is not drawing air. A vent passageway allows air to flow between the valve control chamber and the compression cylinder inlet when compression is begun at the start-up of the compressor unit or at the loading of the idling compressor unit. A vent orifice restricts the flow of air from the valve control chamber to the compression cylinder inlet.

Abstract: An oil pump for an automatic transmission includes a pump body having a pump chamber, a pump cover disposed so as to oppose to the pump body, an inner rotor disposed in the pump chamber and driven by a driving force from a torque converter and an outer rotor meshed with the inner rotor. The pump body includes a pump suction port, a pump discharge port a first oil, passage for supplying oil from a oil pan to the pump suction port, a second oil passage for returning excess oil of a first regulator to the first oil passage and a third oil passage having an outlet port for retuning excess oil of a second regulator to the pump suction port.

Abstract: A pump includes a cylinder, a piston, a rod, a handle, a nozzle and a pressure gauge. The piston is received in a space extending through the cylinder. To pump, the piston is reciprocated in the cylinder. The rod is connected with the piston so that the piston is moved via operating the rod. The handle is connected with the rod for facilitating the operation of the rod. The nozzle is in communication with the cylinder. A pressure gauge can be engaged with and disengaged from the nozzle. A flow control unit is in communication with the nozzle for detachable engagement with the pressure gauge. The flow control unit provides an open position when engaged with the pressure gauge and a closed position when disengaged from the pressure gauge.

Abstract: An air compressor includes a machine base, a transmission device, a cylinder, a valve, an automatic pressure-releasing valve and a manual pressure-releasing valve. When a pressure gauge indicates that air pressure is excessive, surplus pressure can be released either by the automatic pressure-releasing valve or by the manual pressure-releasing valve, able to protect the components in the air compressor from damaged and ensure safety of a tire receiving compressed air from the air compressor.

Abstract: The present invention relates to an improved structure of an accurate air pump indicating pressure, especially one balancing pressure of tire and that indicated on panel. The present invention consists mainly of a stopping valve, a check valve, and a flowing pressure tube. The stopping valve is found inside the chamber between the air pump and the tire in order to balance tire pressure and moving pressure. The check valve is found at the front part of the air pumping tube in order to control moving pressure; and the flowing pressure tube is found inside the air pumping tube which is made of elastic tubes and springs. Hence, the present invention of an improved structure of an accurate air pump indicating pressure can balance pressure of tire and pressure of panel.

Abstract: The present invention relates generally to variable discharge pumps, and specifically pumps used in fuel injection systems. Typically, such pumps include a dedicated spill control valve for each pumping plunger, that also doubles as an avenue for refilling the pumping chambers. This double duty results in compromise in the design of the spill control valve to operate effectively in both spill and fill modes. The present invention addresses these issues by utilizing a shuttle valve member to allow the spill function and the fill function to be addressed in separate passageways while also allowing a pair of plungers to share a common spill control valve. The present invention find particular application in pumps used to supply high pressure fluid to common rails for fuel injection systems.

Abstract: A pump capable of releasing excessive air is shown to include a hollow base, a cylinder installed on and communicated with the hollow base, a piston movably received in the cylinder, a piston tube including a lower end connected with the piston and an upper end located beyond the cylinder, a tube including a lower end communicated with the hollow base and an upper end inserted into the piston tube through a channel defined in the piston, a release valve mounted on the upper end of the piston tube and a handle mounted on the upper end of the piston tube. The valve is installed on the handle so that it can be touched conveniently and operated easily by a user who is using the pump.

Abstract: A valve designed to limit inadvertent operation of the valve. The valve has a shortened plunger, a collar to prevent tilt of the plunger, and a conformable ring on the valve face. The plunger is provided with a groove sized and dimensioned to partially receive the inner surface of the ring.

Abstract: In a compressor at least one bypass valve is arranged in a low-pressure zone inside a casing of the compressor. The bypass valve defines a chamber connected by a first duct to at least one compression pocket situated in the peripheral zone of the compression stage and by a second duct to the low-pressure zone, the two ducts opening near one another so that they can be shut off by a shutter which can move in the chamber, being guided by the walls that delimit this chamber, a third duct intended for conveying a shutter-control fluid opening into the lower wall of the chamber of the valve. The shutter is opened by gravity when no control fluid is applied.

Abstract: The invention is drawn to an apparatus for supplying fluid, such as air, under pressure to a fluid accommodating means such as an air mattress and automatically adjusting the fluid pressure. The apparatus has a coupling device which attaches the apparatus to the air mattress. A housing encloses a motor, an impeller, a two-way valve and a solenoid. The solenoid opens the two-way valve to allow inflation or deflation of the air mattress. The motor is reversible and the impeller is used to force fluid into or out of the mattress. A controller is used to inflate and deflate the mattress. The controller can be attached to the apparatus or it can be a remote control.

Abstract: A fluid pump, wherein a cylinder supporting a plunger and a pump housing are formed with dissimilar metals and a pressing mechanism to press the cylinder and the pump housing relatively to each other is provided so that a pressurizing chamber is sealed through a pressing surface between the pump housing and the cylinder, whereby the number of seal points can be reduced and a reduction in reliability can be eliminated while realizing a reduction in weight of the pump housing and a reduction in cost due to increase in cutting capability using a soft member such as aluminum alloy for the pump housing.

Abstract: A pump includes a cylinder, a piston assembly, a first nozzle, a valve, a controller, a ring and a second nozzle. The cylinder defines first and second chambers and first and second channels for communication between the chambers. The piston assembly is received in the first chamber. The first nozzle defines a channel. The valve is received in the first chamber. The controller defines an axial channel and a radial channel communicated with the axial channel, and is received in the second chamber and linked to the valve through the second channel. The controller is movable between a first position for allowing the valve to seal the second channel and a second position for driving the valve to open the second channel. The ring is mounted on the controller so as to divide the second chamber into a first portion for communication between the first channel and the channel of the first nozzle and a second portion for communication between the second channel and the radial channel of the controller.

Abstract: The present invention provides a piston type small discharge pump capable of reducing a dead volume and effects of unbalanced load to the piston shaft, and being self-priming. The fluid taken through a inlet port is introduced into a cylinder portion via a flat type check valve, and discharged into a discharge port through a discharge hole and a check valve as a piston moves up and down. A flat type check valve is provided in the vicinity of a bottom dead center of the piston and a spring for biasing the piston upwardly is provided outside the cylinder portion, thus reducing the dead volume.

Abstract: The present invention relates to a hydraulic unit, in particular for slip-controlled automotive vehicle brake systems, including a pump and an electric motor for driving the pump, wherein the drive of the electric motor extends into a crank chamber of the pump, and including ventilation and venting of the crank chamber for the purpose of pressure compensation in relation to the atmosphere using a pressure compensation channel. The pressure compensation channel is connectable to the atmosphere by way of inlet and outlet valves which are closed in their basic position and responsive to the pressure differential.

Abstract: A gas compression apparatus for a reciprocating compressor includes a reciprocating motor generating a linear reciprocal driving force, a compressing cylinder positioned within a predetermined distance from the reciprocating motor, a position controlling cylinder positioned within a predetermined distance from the compressing cylinder, an initial position variable type piston inserted into the compressing cylinder and the position controlling cylinder, and being linearly and reciprocally moved within the compressing cylinder and the position controlling cylinder, and a pressure controlling valve controlling a pressure inside the position controlling cylinder with the pressure of the gas discharged from the discharge chamber.

Abstract: A fuel system arranged to deliver fuel at high pressure to a fuel injector through a high pressure fuel line defined, at least in part, within first and second housing parts of a pressure relief valve arrangement. The first and second housing parts define first and second separable valve surfaces respectively. A clamping arrangement is provided for applying a clamping load to the first and second housing parts so as to urge first and second valve surfaces respectively thereof into substantially sealing engagement. The clamping arrangement is arranged to permit separation of the first and second valve surfaces in the event that fuel pressure within the high pressure fuel line exceeds a predetermined amount, thereby to permit fuel within the high pressure fuel line to flow to a region of relatively low pressure to relieve fuel pressure within the high pressure fuel line.

Abstract: An inflatable shoe with a deflation valve designed to limit inadvertent operation of the valve and thereby limit inadvertent deflation of the shoe. The deflation valve has a shortened plunger, a collar to prevent tilt of the plunger, and a conformable ring on the valve face. The plunger is provided with a groove sized and dimensioned to partially receive the inner surface of the ring.

Abstract: A piston pump comprised of a cylinder (2), an automatically closing intake valve (3) to a pump chamber (4), a sealing reciprocating piston (5) and a sealing upstream filter piston (7), wherein the piston (5) together with the filter piston (7) are elastically spring-biased and axially limitedly moveable and form together with the filter piston (7) an automatically closing discharge valve (8).

Abstract: Several transmission embodiments selectively communicate rotary drive to an orbiting scroll to achieve capacity modulation. In these embodiments, when the motor is driven in a first direction, the orbiting scroll is driven at a rate which is equal to the motor speed. However, if the motor is driven in a reverse direction, the orbit rate of the orbiting scroll is reduced. The transmission ensures that the orbiting scroll member itself is driven in the proper forward direction regardless of whether the motor is being driven in forward or reverse.

Abstract: An unloader system is provided for a reciprocating gas compressor. The system includes an unloader valve assembly including a valve member controlling flow between compressor cylinder and a clearance bottle. Opening and closing of the valve member is controlled by manipulating a control pressure acting through a manifold against the stem of the valve member by means of a pressure regulator connected in series with a pressure source. When the pressure in the compressor cylinder acting on the heads of the poppet valve members exceeds the control pressure acting on the stems, the poppet valve members open, partially unloading the compressor.

Abstract: The invention relates to a process for conveying damp gases by means of a conveyor device (1) and also relates to a conveyor device (1) for carrying out the process. The conveyor device (1) has at least one feed pump (2) with an oscillating reciprocating piston (3) in a delivery chamber (7). In order to dry the conveyor device (1) effectively in the region of the delivery chamber (7), the delivery chamber (7) of at least one feed pump (2) is intermittently ventilated at various intervals in time using an ventilation device (15) while the conveyor device (1) is in operation.

Abstract: A pressure equalization method and system is provided for starting a compressor while maintaining the compressor at a high pressure and comprises a valve and a bleed port. The compressor has a compressor inlet for receiving a fluid at a first pressure and a compressor outlet for discharging the fluid at a second pressure, and is operable to compress the fluid from the first pressure to the second pressure. The valve is proximate to and in fluid communication with the compressor outlet and is movable to an open position when the compressor is operating to allow the fluid at the second pressure to flow through the valve and is movable to a closed position when the compressor stops operating to prevent backflow of the fluid at the second pressure through the valve toward the compressor inlet. The bleed port is upstream of the valve and in fluid communication with the compressor inlet to equalize the pressure of the fluid contained in the compressor when the compressor stops operating.

Abstract: A two-way manually operated pump structure consisting of a pump body, a nozzle mount, a control ring mount, and other structural components that are assembled together, in which rotating the control ring mount shifts the air direction between them and thereby enables manual inflation and deflation operation.

Abstract: A micropump underpressure control device, working in conjunction with a micropump having an inlet and an outlet. The micropump underpressure control device comprises a control valve and a transmission tube. The control valve is installed at a supply pipe leading to the micropump and further comprises a case with a membrane, a valve assembly, a connecting rod and a spring. The membrane is exposed to pressure from the outlet of the micropump and accordingly deformed, via the connecting rod controlling opening and closing of the valve assembly, so that working liquid is allowed to proceed to the inlet of the micropump or blocked. The transmission tube transmits pressure at the outlet of the micropump to the membrane. On an opposite side, the membrane is pressed on by working liquid and by the spring. Thus pressure at the inlet of the micropump is controlled, being kept smaller than or equal to pressure at the outlet of the micropump by a fixed difference.

Abstract: When a piston unit and a valve unit employed in a recording head of an ink-jet recording apparatus were manufactured by a conventional method, comprising parts for these unit were separately formed and assembled, which required considerable man-hours for the assembly and measures to prevent contamination by foreign particles during the assembly. The present invention is carried out to solve these problems and provides units at less expensive cost. In order to attain above-mentioned objectives the units are formed out of mutually insoluble materials with other parts by an insert molding or a multi-color molding. By employing forming materials with different molding shrinkage rate, desired gas-tightness of the units are attained by keeping moving performances of the units almost intact. In addition a rubber or an elastomer is employed as a material for a part which requires a gas-tightness and flexibility.

Abstract: An engine prelubrication pump includes a pump housing with a pump cavity in which a first and second gear are positioned for pumping fluid. The first gear is operably and sealably connected to a motor for rotation and the second gear is rotatably mounted to a second shaft for geared rotation with the first gear. Fluid inlet and outlet ports are located in communication with the pump cavity and adapted respectively for connection with a source of fluid and a discharge means and an internal vent is positioned in between the armature shaft of bore and the pump housing along the inlet port. Alternatively, a valve is positioned between the inlet and outlet ports to selectively permit fluid pumped between the inlet and outlet ports to pass through when the outlet port is flow restricted.

Abstract: The invention is based on a radial piston pump (1) with a pump body (2), in which pump body (2) are placed pistons (4), and cylinders (5) arrayed radial to a cam (14) and the pistons (4) upon an inward thrust suck in fluid by means of suction side intakes (17) and upon an outward thrust, the pistons (4) impel fluid through pressure openings (7) in the outer end walls (6) of the cylinder (5) into a plenum (10) whereby the check valves (22) are formed from an annular coil spring valve (9) which cover the pressure ports (7) and the thereto connected stress relieving corrugations (8), and upon the exceeding of a specified threshold transport pressure, the respective pressure opening (7) opens to the plenum (10). The proposal is made, that a stress relieving zone (27) of a piston-cylinder unit (4, 5) be connected to the pressure zone (5, 7, 26) of a neighboring piston-cylinder unit (4, 5).

Abstract: A Lysholm compressor is provided with a rotor 5 in which a spiral tooth groove 5a is formed in order to form a tooth groove space 7, the rotor 5 taking-in and compressing a fluid in the tooth groove space 7, a discharge port 9 which discharges fluid which is compressed by the rotor 5, a bypass path 11 which communicates the discharge port 9 and the tooth groove space 7, and an outlet portion 13 of the bypass path which faces the discharge port 9. The outlet portion 13 has a pipe shape which projects out into the discharge port 9. An outer peripheral portion of an end portion of the pipe-shaped bypass path outlet portion is tapered so as to become narrow toward a distal end.

Abstract: In a variable displacement compressor of a piston type, a valve body (34) is movably placed adjacent to a main channel (32) communicating a suction port (26) with a suction chamber (24). The valve body is for variably controlling an opening area of the main channel. A fluid damper (38) is coupled to the valve body to damp vibration of the valve body. In addition, a bypass channel (39) is formed outside of the air damper to communicate the suction port with the suction chamber.

Abstract: An air compressor comprises a compressor main body, and a capacity adjusting apparatus connected to an intake side of the compressor main body for adjusting the intake air flow into the compressor main body. The capacity adjusting apparatus is provided in an intake pipe. The intake pipe is adjacent to a discharge pipe of the compressor. A communicating passage is formed in the adjacent portion so as to introduce the compressed air discharged from the discharge pipe into the intake pipe system. The intake pipe is provided with an opening port for limiting the intake air flow into the compressor main body. The capacity adjusting apparatus opens and closes the communicating passage and the opening by means of an intake port switch valve and a discharge ventilating port switch valve which are provided in an end portion of the capacity adjusting apparatus.

Abstract: A radial piston pump for high-pressure fuel delivery in fuel injection systems of internal combustion engines, which includes a common rail injection system. The system includes a drive shaft that is supported in a pump housing and is embodied eccentrically for driving a number of pistons that are disposed radially in respective cylinder chambers into a reciprocating motion in the radial direction in the cylinder chambers upon rotation of the drive shaft. For each piston, a metallic housing part which constitutes the respective cylinder chamber is provided with a fuel intake opening and a fuel outlet opening which are controlled by intake and outlet valves. In order to uncouple the high-pressure sealing points from one another and to respectively define them in a statically exact fashion, the pump is embodied so that the housing part rests with a flat contact surface against a flat contact surface of the metallic housing base body.

Abstract: A high-volume low pressure hand operated air pump comprised of a tube body with a plunger shaft inserted into one end thereof and a check valve at the other end thereof with a floating seal secured to the internal end of the plunger shaft comprised of a captured double sided annular disk having a closed cell foam plastic seal on one side thereof and a plastic stiffener of the same plastic material integrated thereto for supporting the foam sealing side thereof

Abstract: A lubricating oil supplying device allows for the oil discharge amount to be more finely controlled by provision of many outlet ports, and by reducing the influence of vibration. Therefore, a spool valve unit and a pump are separately formed. The spool valve unit includes an open-close spool valve and a solenoid for controlling operation of this spool valve. Plural inlet passages and an outlet passage are formed in the spool valve. The spool valve opens or closes the inlet passages, and oil from the pump is introduced into these inlet passages. One side of the outlet passage communicates with the inlet passages, and the other side communicates with an engine. A passage for introducing the oil from an oil tank to a pump chamber is formed in the solenoid. When the solenoid is turned “OFF”, communication between the return passage and the inlet passages is interrupted by the spool valve, and the oil is discharged from the pump to the plural inlet passages.

Abstract: A variable pressure oil pump assembly for use with a vehicle having a controller includes a pump body having an inlet, an outlet, a valve chamber, a first passage disposed between the inlet and the valve chamber, and a second passage disposed between the outlet and the valve chamber. The assembly further includes a pressure relief valve subassembly having a movable plunger that is disposed at least partially in the valve chamber for controlling flow of oil through the valve chamber so as to control outlet oil pressure at the outlet. A plunger adjustment mechanism is associated with the valve subassembly and adapted to communicate with the controller. The plunger adjustment mechanism is operable to control movement of the plunger based on control signals provided by the controller.

Abstract: This present application discloses an improved valve configuration such that an indicator port is incorporated directly within the valve allowing a sensing device to be mounted directly to the valve or within the valve body, this application being directed to both suction and discharge valves which sense at least one condition within a compressor comprising a cylinder, a piston, at least one discharge valve, and at least one suction valve, the valve further including a valve guard, a valve seat, a hollow area adapted and configured for housing a sensing device and a sensing device disposed within the hollow area.

Abstract: The invention relates to a valve arrangement with a pressure limiting valve and a flow regulator valve, which comprises a flow regulator piston, having at least one first hydraulic resistor, distinguished in that the flow regulator valve's (5) flow regulator piston (15) has a split pressure return surface and in that the first part (ring surface (45)) of the pressure return surface is capable of working at a pressure p1 and a second part (annulus surface (31)) of the pressure return surface is capable of working at a pressure p2.

Abstract: A first bypass valve (27) that sets discharge capacity to 60% is provided in a first scroll 21 of an asymmetrical spiral-type scroll compressor. Also, a second bypass valve (40) that makes suction side and discharge side communicated with each other so that set load of the compressor becomes 50% is provided outside a scroll of the first scroll (21). In this way, by closing the first and second bypass valves (27, 40), effective load of the compressor is set to 100%. Also, by opening the first bypass valve (27) and concurrently closing the second bypass valve (40), the effective load of the compressor is set to 60%. Further, by opening both the first and second bypass valves (27, 40), the effective load of the compressor is set to 30%.

Abstract: An inflatable shoe with a deflation valve designed to limit inadvertent operation of the valve and thereby limit inadvertent deflation of the shoe. The deflation valve has a shortened plunger, a collar to prevent tilt of the plunger, and a conformable ring on the valve face. The plunger is provided with a groove sized and dimensioned to partially receive the inner surface of the ring.

Abstract: A variable displacement pump (28) having a combination inlet port (71) and an outlet (76) formed integrally on the rear body (32). By integrating the combination inlet port (71) and outlet (76) on the rear body (32), this invention simplifies the manufacture of the pump (28) as compared with known variable displacement pumps.

Abstract: A variable displacement swash plate type compressor which incorporates a conduit formed in the cylinder block to provide fluid communication between a crank chamber and one or more cylinders to eliminate the need for an orifice tube in fluid communication between a discharge chamber and the crank chamber and to increase the flow of refrigerant gas and lubricating oil to the crank chamber under all operating conditions and to increase the internal fluid pressure in the crank chamber.

Abstract: A fluid pump includes a pump housing with a pump cavity in which a first and second gear are positioned for pumping fluid. The first gear is operably connected to a motor for rotation and the second gear is rotatably mounted to a shaft for geared rotation with the first gear. Fluid inlet and outlet ports are located in communication with the pump cavity and adapted respectively for connection with a source of fluid and a discharge means. A bypass valve is positioned between the inlet and outlet ports to selectively permit fluid pumped between the inlet and outlet ports to pass through it when the outlet port is flow restricted. The bypass valve is normally closed to fluid pumped by said first and second gears to flow from said inlet port to said outlet port, but is opened to permit flow to cavitate when not desired to pump.