Abstract: A progressing cavity pump or a motor includes, in one embodiment, an outer tube 12, an inner tube 14, and a plurality of apertures 16. A pair of annular seal glands 18 seal the stator material to the outer tube. The stator material is injection molded into the inner tube and passes through the plurality of apertures and into an annular gap between the inner tube and the outer tube. In other embodiments, the outer housing for a progressing cavity pump or motor is provided with one or more grooves, with each groove having an outer surface radius less than the outer housing surface radius. A plurality of apertures are provided in fluid communication with the grooves. According to the method of the invention, the stator material is injected into the apertures and fills a space radially outward of the apertures to bond the stator materiaal to the outer housing.

Abstract: A check valve is provided to each discharge port, which communicates between a corresponding working chamber and a high pressure chamber in an integrated compressor/expander apparatus. A valve mechanism, which is opened in a motor mode, is provided to communicate between the working chamber and the high pressure chamber.

Abstract: A discharge valve system of a scroll compressor comprises: a fixed scroll having a discharge hole and discharge bypass holes; a discharge valve assembly mounted at the fixed scroll, for opening and closing the discharge hole by a pressure difference; and an integral bypass valve assembly mounted at the fixed scroll, for opening and closing the bypass holes and interworking the discharge valve assembly. According to this, a discharge amount of gas is maximized in a low pressure ration driving of the scroll compressor thereby to enhance a discharge efficiency. Also, the number of components is greatly reduced thus to reduce a fabrication cost. Also, the number of assembly processes is greatly reduced thereby to enhance an assembly productivity.

Abstract: An apparatus for varying the capacity of a scroll compressor is disclosed. The apparatus for varying the capacity of a scroll compressor includes a bypass passage for connecting a compression pocket under intermediate pressure among compression pockets formed by a wrap of a fixed scroll and a wrap of a orbiting scroll and a suction side through which refrigerant is inhaled into the compression pocket to each other, an opening and closing device for opening and closing the bypass passage, and an elastic opening and closing device mounted in the bypass passage to open and close the bypass passage by the pressure of the compression pocket and the pressure and elasticity of the suction side according as the bypass passage is opened and closed by the opening and closing device. Therefore, it is possible to simplify the structure of varying the capacity of a compressor such that it is possible to reduce the size of the apparatus for varying the capacity of a scroll compressor and to thus reduce the number of parts.

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: A scroll type compressor with an enhanced sealing arrangement includes two sealing rings, mounted one between a first part of a gliding block and a first chamber of a fixed scroll and another one between a second part of the gliding block and a second chamber of the fixed scroll, respectively. The sealing ring has a U-shape cross section characterized in having a center depth smaller than half of a total height of the cross section. By providing such sealing rings, damage in mounting the sealing rings can be reduced to a minimum, possible leakage from the damage can be avoided, the assembly process in producing the compressor can be improved, and the compressor can be successfully merchandized.

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 (100*) having a pump (10*), such as a variable-displacement vane pump (10*) or a gear pump. The pump (10*) in turn has hydraulic pressure-control dissipating devices (29, 30) for imparting to the oil in a first control chamber (22) a pressure (p2) lower than the pressure of a second chamber (20). The system (100*) is characterized in that the first control chamber (22) of the pump (10*) has a channel (40) connecting the first control chamber to an oil inlet (23). And the channel (40) has an opening/closing device (41) controlled selectively by an engine operating parameter, such as oil temperature.

Abstract: An apparatus for varying the capacity in a scroll compressor, the apparatus having an orbiting scroll provided with a wrap filling portion which is stepped at a certain height, extending the entire inside of a wrap from an outer end portion of the wrap; a fixed scroll provided with a stepped wrap obtained by stepping a wrap corresponding to the wrap filling portion of the orbiting scroll and being in meshing arrangement with the orbiting scroll; a connection passage for connecting compression pockets formed by the outer wrap portion of the orbiting scroll and the inside of the wrap of the fixed scroll opposed to the outside of the outer wrap portion with the suction opening; and an opening/closing unit for opening or closing the connection passage such that the suction opening side and the compression pockets can be connected and disconnected to each other.

Abstract: Disclosed is a step-type capacity varying apparatus of a scroll compressor comprising: an orbiting scroll having a first filling portion step-formed with a constant height from an outer end portion of a wrap towards an inner side of the wrap, and a second filling portion extendingly formed at the first filling portion with a certain length from the outer end of the wrap; a fixed scroll engaged with the orbiting scroll by being provided with a stepped low wrap corresponding to the first filling portion and the second filling portion of the orbiting scroll; and an opening/closing unit for opening and closing a passage formed by the second filling portion of the orbiting scroll and the stepped low wrap of the fixed scroll. According to this, a fabrication cost is lowered, a capacity variation width is greatly increased, and an operation is facilitated.

Abstract: A compressor is provided with an oil separator for separating part of the lubricating oil contained in the compressed refrigerant, path arrangement for connecting a separation chamber of the separator and a delivery port of the compressed refrigerant, the path arrangement having a plurality of linear holes with opening ends that open in the outer surface of the housing wall, and screw plugs closing the opening ends except for the one serving as the delivery port, and a safety device built in at least one of the screw plugs, the safety device having a pressure relief valve and/or a temperature sensor.

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 returning excess oil of a second regulator to the pump suction port.

Abstract: Scroll compressors are provided with vapor injection or by-pass ports that will allow greater flow of refrigerant through the port than was the case in the prior art. The prior art has typically utilized a single injection port having a diameter equal to or slightly larger than the thickness of the scroll wrap. In this way, the scroll wrap is able to prevent or restrict cross-flow leakage from the port from passing between the two compression chambers. However, this single port has also limited the amount of refrigerant that can be returned. In one embodiment, the present invention utilizes a plurality of ports generally spaced along the length of the wrap such that cross-flow can still be prevented while providing a greater cross-sectional flow area into or out of the compression chambers. In another embodiment, the several ports may be replaced by a single elongated port.

Abstract: An oil-injection screw compressor in which oil is mixed into compressed gas, in order to prevent back flow during the no-load running and stoppage of the compressor body while contributing to a cost reduction, comprising: a compressor body; a motor for driving the compressor body; an inverter for variably controlling the number of revolutions of the motor; a blow-off valve disposed on the discharge side of the compressor body and capable of releasing a quantity of air beyond the discharge capacity of the compressor body when operating of the motor at the minimum number of revolutions; a suction non-return valve which, disposed on the suction side of the compressor body, is closed when it is at a stop; and a pressure sensor for detecting the discharge side pressure of the compressor body; and, a controller which, at the time of operation of the motor at the minimum number of revolutions, opens the blow-off valve when the discharge side pressure P detected by the pressure sensor has risen to a prescribed upper

Abstract: A screw vacuum pump which allows reduced power, lower inside gas temperature, and reduced discharging time. The pump has a pair of screw rotors rotatively engaged with each other in a pump casing to discharge a gas along a longitudinal direction of the pump. Each rotor has three types of helical teeth serially located in a longitudinal direction of the rotor and different from each other in theoretical displacement volume. A bypass conduit communicating with a delivery side of the pump is connected via a first check valve to a first intermediate space defined between the first helical teeth and the second helical teeth and via a second check valve to a second intermediate space defined between the second helical teeth and the third helical teeth. The gas is compressed at the third stage to half the first stage volume before a discharge port opens.

Abstract: A rotating vane vacuum pump has a secondary inlet (4) which permits additional suction after the primary inlet (3) has closed.

Abstract: A scroll compressor with a backflow-proof mechanism. The scroll compressor comprises a slider disposed on a scroll couple, forming several enclosed spaces. The slider is raised by the working fluid in the spaces, preventing liquid leakage from a high-pressure chamber to a low-pressure chamber, when the scroll compressor starts. The slider descends when the compression ratio of the scroll compressor is exceeded. Thus, the pressure is released, and the performance of the scroll compressor is improved. The slider of the invention further comprises a floating element to prevent reversal of pressurized fluid and damage to the scroll couple.

Abstract: A scroll compressor having a vacuum preventing structure includes: a casing forming a receiving space therein; a fixed scroll fixed to a main frame installed in the casing, and including a back pressure passage at an outer side surface thereof, a discharge pressure hole formed at one side of the back pressure passage such that the back pressure passage and a discharge pressure space of the casing can communicate with each other, a middle pressure hole formed at another side of the back pressure passage such that the back pressure passage and a compression space of the casing can communicate with each other, and a suction pressure hole formed at still another side of the back pressure passage such that the back pressure passage and a suction pressure space can communicate with each other; an orbiting scroll positioned between the fixed scroll and the main frame and forming a compression space by being coupled with the fixed scroll; a piston slidably installed in the back pressure passage, for opening or closin

Abstract: A variable capacity pump/motor has a meshing internal and external gear set disposed between an upper mandrel and a lower mandrel, each including a flange extending towards the gears to divide a pump/motor chamber into suction and discharge chambers. The outer gear is fixed and the internal gear is axially moveable with respect thereto. The inner gear and the upper mandrel move in response to changing pressures in the casing, allowing the motor to vary displacement and the pump to vary its output based on supplied fluid pressure or based on the speed of the prime mover. An external configuration includes a pair of meshing gears mounted on separate shafts in a casing. One gear is fixed and the other is axially moveable with respect thereto and moves in response to changing pressures in the casing. Each of the gears is sealed by a seal/bushing on a free end thereof.

Abstract: An apparatus for preventing a vacuum state in a scroll compressor including a hermetic container divided into a high pressure space and a low pressure space; a fixed scroll provided inside the hermetic container; and an orbiting scroll orbiting in a state of being interlocked with the fixed scroll, comprises: a connecting passage for connecting the high pressure space, the low pressure space and a compression pocket to each other, wherein the compression pocket is formed by a wrap of the fixed scroll and a wrap of the orbiting scroll; a slider movably inserted in the connecting passage, for allowing the high pressure space and the low pressure space of the hermetic container to communicate with or be blocked from each other by a pressure difference between the low pressure space of the hermetic container and the compression pocket; and an elastic support means for elastically supporting the slider, thereby preventing vacuumization of the inside of the hermetic container in operation, and making a smooth opera

Abstract: A rotary screw vacuum pump system includes a vacuum bypass system, which communicates with a first closed cell formed by the rotor system. An air bypass valve within an air communication conduit is controlled by a solenoid valve that operates in response to a pressure switch. The pressure switch is in communication with a vacuum pump suction conduit that draws suction for a suction system attached thereto. The solenoid valve is activated by the pressure switch at a vacuum level slightly below the point at which the undesirable cavitation noise generated at terminal vacuum condition begins.

Abstract: An electric oil pump apparatus includes a pump housing a drive side communicating portion, a motor housing having a pump side communicating portion communicating with the drive side communicating portion, a bearing portion arranged at one of the drive side communicating portion and the pump side communicating portion, and a shaft rotatably supported by the bearing portion. A one end of the shaft extends in the pump housing and is provided with a drive rotor capable of feeding the oil in response to rotation of the shaft. The other end of the shaft extends in the motor housing and is provided with a permanent magnet.

Abstract: An engine pump is provided which operates with an internal combustion engine or as a supplemental pump or as used in a stand alone device, and includes an internal vent for improved pump and motor durability. The pump is operably and sealably connected to a motor and adapted for connection with a source of fluid and a discharge means. An internal vent is positioned in between an armature shaft of bore along an inlet port thereby decreasing the pressure in the area of the seal. 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: Disclosed is a vacuum preventing device including a housing engaged to one side of an outer circumference portion of a fixed scroll to divide the area into a discharge region and a suction region, a chamber formed in the housing and having a compression hole connected to a compression region at one side therein, a suction hole connected to a suction region at the other side therein, and a discharge hole connected to a discharge region at a middle side therein, an open/close member is movably installed in the chamber to selectively connect the discharge hole to the suction hole, and an elastic member is installed in the chamber to provide an elasticity force to the open/close member.

Abstract: A variable displacement pump has a cam ring, a rotor, a plurality of vanes, a pressure plate and a rear body. The cam ring is accommodated within a pump body. The rotor rotates within the cam ring. The plurality of vanes are inserted retractably into slits formed at regular intervals circumferentially in the rotor. The pressure plate and the rear body carry the cam ring and the rotor. A circular groove communicating to a back pressure inlet bore on a bottom portion of the slits is formed in a suction area on a face of the rear body on a side of the rotor. The groove is communicated via a communication passage to a passage between a power steering gear and a tank T to introduce a working oil after used in the power steering gear.

Abstract: In an oil pump apparatus, a drain outlet is positioned outwardly from an inner peripheral surface of a suction passage or from an extended line thereof at a sectional view which takes along an orthogonal direction relative to a central axis of the suction passage and which shows the drain outlet, and/or the drain outlet is positioned at a side of a shaft aperture to be away from an imaginary line connecting a central axis of a discharged passage and a central axis of the suction passage at a sectional view which takes in parallel with the central axis of suction passage and which shows the drain outlet, such that the opening center of the drain outlet is not overlapped on the imaginary line.

Abstract: A control device for a positive displacement pump includes a throttle device and a flow control valve. The flow control valve includes a flow control piston and is configured to regulate an unrequired excess flow of the pump at an increased speed. The throttle device is configured to produce a speed-related pressure differential in a bore section, the pressure differential being responsible for the displacement of the flow control valve and the throttle device. The throttle device is arranged in the pressure outlet (bore section) of the pump and includes a regulating pin connected to the flow control piston, having a control contour configured so that a modifiable through cross-section is created in association with a throttle bore. The control pin has a wider section in an axial displacement area of the throttle device, the area not being involved in control of the volume flow, whereby a minimum obturating section arises in the displacement area.

Abstract: An engine unit case includes a housing configured to be assembled to a cylinder block of an engine, an oil pump provided at the housing, and a pressure adjusting mechanism for adjusting discharge pressure of the oil pump. The housing is unitarily formed with a pump chamber of the oil pump and a body of the pressure adjusting mechanism.

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: An apparatus for changing capacity of scroll compressor comprises: a seal member movably installed on one of facing surfaces of a fixed scroll so as to seal a compression space made by the fixed scroll and orbiting scroll; a back pressure passage formed to be communicated from a point, where the seal member is contacted, to an outer circumferential surface of fixed scroll; an exhaust pipe installed on outer circumferential surface of the fixed scroll to be communicated with back pressure passage; and an exhaust pipe opening/closing valve installed on center part of exhaust pipe to open/close the exhaust pipe selectively, and thereby, sealability can be improved and low capacity can be outputted without decelerating orbiting scroll in low capacity operation.

Abstract: For a purpose of realizing a refrigerant cycle apparatus capable of exactly detecting a pressure reverse phenomenon caused in a compression element of a compressor of a multistage compression type, in the refrigerant cycle apparatus in which the multistage compression type compressor constitutes a refrigerant circuit, including an electromotive element, and first and second compression elements driven by the electromotive element in an airtight container to suck an intermediate-pressure refrigerant gas compressed by the first compression element into the second compression element and to compress and discharge the refrigerant gas, the apparatus comprising: a sensor for detecting a discharge refrigerant pressure of the first compression element; and a control device into which an output of the sensor is input, the control device detects reverse of the discharge refrigerant pressures of the first and second compression elements based on the discharge refrigerant pressure of the first compression element.

Abstract: A vacuum preventing device of a scroll compressor includes: a chamber formed at one side of a fixed scroll and having a suction pressure hole, a middle pressure hole and a discharge pressure hole communicating with a suction pressure zone, a middle pressure zone and a discharge pressure zone, each formed at a certain portion of an inner circumferential surface; an open and shut member installed inside the chamber and selectively communicating the discharge pressure hole and the suction pressure hole by virtue of a gas pressure of the middle pressure zone and an elastic force of a spring; and a gas leakage preventing unit for preventing a gas leakage in a normal operation by reducing a clearance between an inner wall of the chamber positioned at the side of the discharge pressure hole and the open and shut member.

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: A self-modulating scroll compressor includes a pair of valves. A first valve moves to a low capacity position when the pressure differential is below a predetermined amount. A second valve moves to a low capacity position when the suction pressure is above a predetermined amount. Low capacity operation will only occur when both valves are open. The present invention thus provides a scroll compressor design with the ability to self-modulate and control the conditions under which low capacity operation occurs based upon two criteria.

Abstract: External gear pump, comprising: a casing (3a, 3b) with a gear chamber (4), comprising an inlet (5) for a fluid on a low pressure side and an outlet (6) on a high pressure side and comprising axial and radial sealing stays (7, 8); toothed wheels (1, 2) being in toothed mesh, wherein the external toothings of the wheels (1, 2) form delivery cells (10) for the fluid which are axially sealed off by the axial sealing stays (7) and radially sealed off by the radial sealing stays (8); and at least one pressure fluid supply (15, 16) through which pressure fluid may be supplied to the low pressure side, wherein the at least one pressure fluid supply (15, 16) opens on the low pressure side into a delivery cell (10) which is radially opposed by one of the radial sealing stays (8).

Abstract: A load-regulating device for scroll type compressors comprising a compressor housing, a bracket body, a partition block, a gliding block, a pair of scrolls and a plurality of air chambers, wherein the gliding block being coupled with the pair of scrolls for defining a plurality of air chambers on the scrolls, the pressure variation in the air chambers is then utilized for causing the motion of the gliding block, enabling the compressor to cause the gliding block by means of the pressure variation to motion upwardly as the compressor is actuated, and preventing the fluid in the high-pressure chamber from leaking towards the low-pressure chamber, thus allowing the compressors to quickly build up the pressure; the gliding block is caused by the pressure variation to motion downwardly at times when the compression ratio is excessively high, so as to relieve part of the load, thus improving the performance and reliability of the compressors.

Abstract: An oil pump apparatus includes a body, a first rotor and a second rotor disposed in the body so as to be able to rotate and a regulator valve mechanism for regulating the pressure of oil discharged to portions of an engine, wherein the regulator valve mechanism is disposed in the inside of the body and the engine and includes a regulator valve member which moves in the direction being in parallel with a rotation as of the first and second rotors in response to the discharged oil pressure.

Abstract: A power steering pump comprises, as main elements, a cam plate, a discharge cover plate and a suction cover plate that cooperate to define a cam chamber, a fluid discharge passage and fluid suction passage for the pump. The cam chamber is formed in the cam plate. The discharge cover plate includes a face that abuts a first face of the cam plate and includes a recess that cooperates with first cam plate face to define a fluid discharge passage. A suction cover plate includes a suction cover face that abuts a second face of the cam plate and comprises a recess that cooperates with the second cam plate face to define a suction passage. The power steering pump further comprises a rotor within the cam chamber and comprising slideable vanes.

Abstract: A variable displacement vane-type fluid pump is provided which permits improved regulation of the pump discharge such that the pump can meet the various requirements of lubrication for internal combustion engines at all speeds with minimized use of power. Of course, the vane pump may also be utilized in a wide range of power transmission and other fluid distribution applications. The variable displacement vane pump of the invention may utilize both hydrostatic and mechanical assistance in radially positioning its vanes to ensure efficient and quiet operation of the pump and to facilitate priming of the pump. The vane pump of the invention may also use both hydrostatic and mechanical actuators to control the position of its containment ring or eccentric ring and hence, regulate the output of the pump.

Abstract: Disclosed is a vacuum preventing device of a scroll compressor comprising: a discharge cover installed at a body of a fixed scroll for dividing inside of a case into a discharge region and a suction region; a vacuum cylinder installed in the discharge cover thus to be connected to a compression chamber formed between the fixed scroll and an orbiting scroll and having a pressure space therein so that the discharge region can be connected to the suction region; a piston movably installed in the pressure space for selectively connecting the discharge region with the suction region by a pressure difference between the compression chamber and the suction region; and an elastic member installed in the pressure space for providing an elastic force to the piston.

Abstract: A self-modulating scroll compressor includes a pair of valves. A first valve moves to a low capacity position when the pressure differential is below a predetermined amount. A second valve moves to a low capacity position when the suction pressure is above a predetermined amount. Low capacity operation will only occur when both valves are open. The present invention thus provides a scroll compressor design with the ability to self-modulate and control the conditions under which low capacity operation occurs based upon two criteria.

Abstract: In a housing of a pump apparatus having a flow control valve to discharge a part of excess fluid in a deviated slanting way to a bypass pass 11, a pair of suction paths 19, 19? is formed opposite to end portions 119, 119? of the bypass path 11 to send operation fluid to suction ports of the pump apparatus. A dividing wall is equipped at opening portions of said pair of suction paths 19, 19? to distribute the operation fluid to each of suction paths 19, 19?. A cross sectional area of one of said opening portions in a side of a direction of said deviated slanting way is smaller than a cross sectional area of the other of said opening portions in an opposite side of the deviated slanting way to relatively restrict a flow of said operation fluid in said one of opening portions.

Abstract: A vacuum pump has a housing and a pump mechanism accommodated in the housing. An exhaust-passage forming portion is located outside of the housing. The exhaust-passage forming portion forms an exhaust passage, which exhaust passage guides gas discharged from the pump mechanism toward the outside of the vacuum pump. A thermal conductor is connected to the outer surface of the exhaust-passage forming portion. The thermal conductor is made of a material having a thermal conductance of which is greater than that of the material for the exhaust-passage forming portion.

Abstract: A pump head for a fluid pump driven by a motor includes an inlet for receiving fluid at a first pressure and an outlet for outputting fluid at a second pressure greater than the first pressure. A relief valve cavity formed in the pump head housing includes a first portion in fluid communication with the inlet and a second portion in fluid communication with the outlet. A relief valve is disposed in the relief valve cavity with no portion of the relief positioned to block or otherwise impede the normal flow of fluid through the inlet or outlet.

Abstract: A self-modulating scroll compressor includes a pair of valves. A first valve moves to a low capacity position when the pressure differential is below a predetermined amount. A second valve moves to a low capacity position when the suction pressure is above a predetermined amount. Low capacity operation will only occur when both valves are open. The present invention thus provides a scroll compressor design with the ability to self-modulate and control the conditions under which low capacity operation occurs based upon two criteria.

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 multistage gear pump for pressurizing fluid includes a housing, a drive shaft and a gear assembly. The drive shaft is rotatably supported in the housing. The gear assembly is disposed in the housing. The gear assembly includes at least first and second gear trains. Each train has a pair of drive and driven gears that are engaged with each other. The drive gear is provided on the drive shaft and followed by the driven gear. The first gear train and the second gear train are arranged so that fluid sequentially passes therethrough as the drive shaft rotates. A theoretical discharge capacity of the first gear train is larger than that of the second gear train.

Abstract: In an oil pump apparatus, a drain outlet is positioned outwardly from an inner peripheral surface of a suction passage or from an extended line thereof at a sectional view which takes along an orthogonal direction relative to a central axis of the suction passage and which shows the drain outlet, and/or the drain outlet is positioned at a side of a shaft aperture to be away from an imaginary line connecting a central axis of a discharged passage and a central axis of the suction passage at a sectional view which takes in parallel with the central axis of suction passage and which shows the drain outlet, such that the opening center of the drain outlet is not overlapped on the imaginary line.

Abstract: A scroll compressor includes a capacity modulation system. The capacity modulation system has a piston that is connected to the non-orbiting scroll that disengages the non-orbiting scroll from the orbiting scroll when a pressure chamber is placed in communication with the suction chamber of the compressor. The non-orbiting scroll member moves into engagement with the orbiting scroll when the chamber is placed in communication with the discharge chamber. The engagement between the two scrolls is broken when the pressure chamber is placed in communication with fluid from the suction chamber. A solenoid valve controls the communication between the pressure chamber and the suction chamber. By operating the valve in a pulsed width modulated mode, the capacity of the compressor can be infinitely varied between zero and one hundred percent.

Abstract: A vent is included into a scroll compressor for protecting a refrigerant system in the event of loss of charge. The vent selectively taps an entrapped compression chamber to a housing chamber which surrounds the motor. In the event of a low charge, the gas in the compression chamber will be at a high temperature, and will heat the motor when the vent opens. The vented heated gas will then actuate a temperature protection device on the motor, causing the motor to stop rotation. In further embodiments, the compression chamber which supplies the tapped fluid is the discharge port.