Abstract: An axle driving system which houses in a housing thereof a hydrostatic transmission, axles, and a driving gear train for connecting output means of the hydraulic transmission and axles, so as to transmit power from a driving source to the hydrostatic transmission and to change the speed, thereby driving the axles. A first chamber therein contains the hydrostatic transmission and a second chamber therein contains the driving gear train. Both the first and second chambers are independent of each other so as to prevent a foreign object, such as iron powder produced in the driving gear train, from entering the hydrostatic transmission. The system includes an L-like-shaped center section on which the hydrostatic transmission is offset such that an imaginary plane which includes a motor mounting surface passes in proximity to the axis of a pump shaft. The pump shaft is disposed perpendicular to the axles. The motor shaft is disposed in parallel thereto.

Abstract: A hydraulic pump includes a housing, at least two pistons mounted to the housing to rotate relative to the housing, and a transition arm coupled to each of the pistons to rotate therewith. The transition arm is set at a predetermined angle relative to a longitudinal axis of the pump. An adjustment mechanism sets the transition arm at the predetermined angle. A cylinder is mounted within the housing to rotate relative to the housing and defines pump cavities for receiving the pistons. A face valve defines inlet and outlet channels in fluid communication with the pump cavities. An apparatus for varying the output volume of a piston assembly includes at least two pistons, a transition arm coupled to each of the at least two pistons, and a rotatable member. The transition arm includes a nose pin, and the rotatable member is coupled to the transition arm nose pin.

Abstract: In a reciprocating-piston machine, in particular a refrigerant compressor for a motor vehicle air-conditioning system, including a machine shaft rotatably supported in a housing, a plurality of pistons arranged circularly around the machine shaft in the housing, and an annular pivoting disc driven by the machine shaft and engaging the pistons via a joint arrangement, the pivoting disc being connected in an articulated manner to the machine shaft via a driver for transmitting the machine shaft drive forces to the pistons and mounted on a machine shaft-supported sliding body so as to be pivotable about a hinge axis oriented transversely to the machine shaft, the sliding body has an elongated recess which is open at one axial end for receiving the driver and the sliding body further includes at its inside adjacent the machine shaft a cavity, which is in communication with a bore forming a discharge passage extending through the machine shaft.

Abstract: Hydraulic device driving a rotating receiver such as a shaft (1) includes at least one hydraulic motor having axial pistons (7) bearing against a fixed swash-plate (9) via shoes (10), the pistons (7) being arranged in a rotating barrel (5), characterized by the fact that the motor shaft (1) carries a toothed crown wheel (2) with which it is integral whose teeth are engaged by teeth (4) provided on the periphery of the rotating barrel (5) of one or more hydraulic motors (7) arranged around the shaft (1), the axis of axes of the barrel (5) being parallel to the axis of the shaft (1).

Abstract: A compressor assembly comprising a housing having a shaft bore therein, a main shaft positioned for rotation within the shaft bore, at least one roller thrust bearing and a thurst surface bearing clip. The thrust surface bearing clip comprises a first position configured for fixed engagement with the housing and a second portion extending from the first portion and configured for supporting a thurst surface in a position spaced from the rotating shaft, the thrust surface providing a bearing surface for the roller thrust bearing.

Abstract: A swash plate plunger type hydraulic motor is constituted such that plungers are slidably disposed in respective plunger holes of a motor cylinder, and a motor rolling member having a motor swash plate member is supported in a motor casing in such a manner that it can tilt and roll. A swash plate tilting angle detector for detecting the angle of a swash plate includes an angle detector mounted to a transmission housing and a rotation connection mechanism for connecting the motor rolling member to the angle detector. The rotation connection mechanism includes a first connection rod which is connected to the motor rolling member coaxially to its tilting and rolling axis, a second connection rod connected to the angle detector, and a movable or universal joint for connecting the first connection rod to the second connection rod.

Abstract: An assembly includes a piston and a transition arm coupled to the piston. The position of the transition arm is adjustable to vary a stroke of the piston. A balance member is adjustable relative to the transition arm to counterbalance the transition arm in varying positions. A control rod is coupled to the transition arm and the balance member. Linear movement of the control rod moves the transition arm in a first direction to change the stroke of the piston and moves the balance member in a second direction substantially opposite the first direction to counterbalance the transition arm. A method of counterbalancing a variable stroke assembly includes moving a transition arm coupled to a piston to vary a stroke of the piston, and moving a balance member in a direction substantially opposite to the direction of movement of the transition arm to counterbalance the transition arm.

Abstract: An axle driving system which houses in a housing thereof a hydrostatic transmission, axles, and a driving gear train for connecting output means of the hydraulic transmission and axles, so as to transmit power from a driving source to the hydrostatic transmission and to change the speed, thereby driving the axles. A first chamber therein contains the hydrostatic transmission and a second chamber therein contains the driving gear train. Both the first and second chambers are independent of each other so as to prevent a foreign object, such as iron powder produced in the driving gear train, from entering the hydrostatic transmission. The system includes an L-like-shaped center section on which the hydrostatic transmission is offset such that an imaginary plane which includes a motor mounting surface passes in proximity to the axis of a pump shaft. The pump shaft is disposed perpendicular to the axles. The motor shaft is disposed in parallel thereto.

Abstract: A rotary hydraulic machine has a swashplate adjustable by an actuator. The swashplate has a part cylindrical bearing surface supported by a complimentary bearing surface in the housing and a fluid bearing acts between the surfaces. The fluid is supplied to the fluid bearing by pressure compensated flow control valves to maintain a predetermined flow of fluid. The actuator includes a pair of single acting hydraulic motors secured in the housing and acting on the swashplate at spaced locations. The pistons of the hydraulic motors engage cylindrical pins located on the swashplate to permit a rolling motion between the swashplate and motors as the swashplate is adjusted.

Abstract: A pair of zero-turn, hydrostatic transaxles (HZTs) that may be joined to form an integrated, zero-turn, hydrostatic transaxle. Each of the hydrostatic transaxles are further comprised of a casing carrying a hydraulic pump driven by an input shaft, a hydraulic motor driven by a the hydraulic pump through porting contained within a center section, and an axle shaft driven by the hydraulic motor. The hydrostatic transaxles are joined along an interface extending generally perpendicularly to the axle shafts.

Abstract: An axial piston machine having a swash plate or oblique axis which can be adjusted by means of servopistons and has a valve segment and an adjustment unit for the electrically proportional adjustment of the volumetric displacement, the adjustment unit comprising proportional magnets which can be activated electrically, and a control piston for controlling the oil pressure which moves the servopistons, the proportional magnets acting on this control piston along a common tappet axis. A feedback device for feeding back the current swash plate or oblique axis valve segment position is provided. The feedback device comprises spring levers and a pointer which can be pivoted about an axis, the pointer which is embodied as a two-armed lever engaging in the control piston on one side of the pivot axis, and between the spring levers on the other side.

Abstract: A fluid machine for a gas compression refrigerating system comprises a first and a second working for performing a pump mode operation, in which working fluid of low pressure is sucked into and compressed by the working chambers. The fluid machine further comprises valve mechanism for selectively forming a motor mode passage in combination with a fluid passage change-over device, so that super heated working fluid of high pressure is introduced into at least one of the working chambers to perform a motor mode operation, in which the high pressure working fluid is expanded in the working chamber to obtain mechanical energy. The fluid machine according to the invention, therefore, performs the pump mode operation at one of the working chambers and at the same time the motor mode operation at the other working chamber.

Abstract: A reciprocating compressor, comprising a cylinder block (1) having a cylinder bore (12) formed therein, a rear head (3) fixed to the cylinder block through a valve plate (2) and having a suction chamber (26) and a discharge chamber (27) formed therein, a front head (4) fixed to the cylinder block (1) and having a crankcase (6) formed therein, pistons (13) reciprocatingly sliding in the cylinder bore according to the rotation of a shaft (7) installed so as to pass through the crankcase (6), a means for separating lubricating oil mixed in working fluid discharged into the discharge chamber (27), and an oil tank (30) for storing the lubricating oil separated by the oil separation means, wherein the lubricating oil stored in the oil tank (30) is cooled by working fluid sucked from the outside and led into the suction chamber (26), whereby the durability of sliding portions can be increased by effectively cooling the lubricating oil in the compressor to assure excellent lubrication at the sliding portions.

Abstract: A torque control for a hydrostatic piston pump that provides for a servo piston rod that is connected to the swashplate of the pump and connected to a servo piston within a first cavity that receives compensation pressure that urges the servo piston toward the swashplate. The servo piston has a stem that extends into a bore and is in contact with the stem of a maximum displacement piston that extends into a second cavity that is acted upon by system pressure to urge the maximum displacement piston toward the swashplate. Additionally, within the second cavity is a set of Bellville washers that surround the stem of the maximum displacement piston to limit the movement of the maximum displacement piston toward the swashplate.

Abstract: In a hydrostatic device using an axial piston pump, a return plate is mounted so that it contacts the movable swash plate of the hydrostatic transmission. The plate is biased by a spring-type mechanism to force the swash plate to return to neutral, and the set position of the plate may be externally adjusted. A bias arm comprising a generally U-shaped member having spring mounted on either leg thereof may be engaged to the return plate.

Abstract: In a variable displacement hydraulic pump having a housing with a multiplicity of interconnected surfaces, including opposed end surfaces and intermediate side surfaces, the improvement comprising the location of at least one case drain orifice in each of a plurality of differing ones of the surfaces in a manner such that at least one of the orifices is located in the vicinity of the top surface of the housing in any spatial orientation of the housing.

Abstract: A pump having a symmetric end cap is disclosed. The end cap is attachable in a first position or a second position wherein the second position is rotated relative to the housing. A trunnion arm extends in a first direction and a system port opens in a first orientation when the housing is connected to the end cap in a first position. The end cap includes structure such that the housing may be connected in a second position so that the trunnion arm extends in a second direction while maintaining the system port opening in the first orientation. The end cap may be provided with a symmetric porting system. A control device for affecting movement of the swashplate is disclosed. Methods of locking the swash plate into a predetermined position are also taught.

Abstract: A hydraulic continuously variable transmission includes a swash plate plunger pump, a swash plate plunger motor, and a closed hydraulic circuit for connecting them to each other, wherein a motor pivoting member is supported by a motor casing so as to be pivotally movable, with the swash plate angle being variably adjustable, to simplify the configuration of a swash plate as much as possible and to widen the swash plate angle range. An inner race of a ball bearing for supporting a transmission output shaft, to which a pump cylinder and a motor cylinder are connected, so that the transmission output shaft is rotatable relative to the motor casing is formed by cutting off an end face portion in the axial direction, on the side of facing the motor pivoting member.

Abstract: To reduce the projection of a swash plate servo mechanism in the radial direction, and to make a hydraulic continuously variable transmission compact, a swash plate plunger pump includes a pump casing provided with an input driven gear. A pump cylinder and a motor cylinder are connected to a transmission output shaft, and a motor pivot member provided with a motor swash plate member is supported to be pivotally movable. A motor servo mechanism includes a ball screw shaft, a ball nut to which an end portion of the motor pivot member is connected, and a swash plate control motor to rotate the screw shaft. A swash plate control motor, located on the side of a hydraulic pump relative to the input driven gear, is mounted to the outside surface of a transmission housing close to the center axis side of a transmission output shaft.

Abstract: A hydrostatic machine with a cylinder block (6), within which sleeve holes (28b) are arranged, in which sleeves (28) sit, surrounding piston bores (28a) in which pistons (29) are mounted, such as to be displaced back and forth and the pistons (29) extend into the cylinder block (5) such as to define cylinders (26) with the front ends thereof. According to the invention, the risk of piston seizure can be reduced, whereby the sleeves (28) comprise an axially-defined recess (41) in the outer surface thereof, in the region facing away from the cylinder and the region with the greatest piston radial force, pressing the pistons (29) against the wall of the piston bore.

Abstract: An improved compact design for a hydrostatic transmission having a hydraulic pump and hydraulic motor mounted on a center section in a housing, wherein the pump and motor are mounted at generally right angles to one another, and the longitudinal axis of the input shaft is located between a first and second parallel planes located at respective ends of the motor shaft and the longitudinal axis of the motor shaft is located between a third and fourth parallel planes located at respective ends of the pump shaft.

Abstract: A swash plate-type compressor included a rotatable swash plate and a piston. The piston is connected to the swash plate via at least one shoe and reciprocates in company with each rotation of the swash plate. The swash plate has a layer of a sintered metal impregnated with a resin on at least a swash plate surface sliding against the at least one shoe. A surface of the impregnated layer is ground.

Abstract: An adjustable arm assembly is drivably coupled to a control shaft and is moved by a link that has a centered position. The arm has two portions that are releasably clamped together. A first arm portion is connected to drive the control shaft. A second arm portion is connected to the link. The adjustment includes a clamp that will releasably clamp the two arm portions together in a fixed position, and an adjustment screw is used to adjust the relative rotational position of the first and second arm portions to move the first arm portion to position the control shaft in a centered position relative to second arm portion, when the second arm portion is in a spring return position. The arm portions are then clamped together.

Abstract: An axial piston micropump is disclosed, having a cylinder drum, in which several cylinders are provided a swash plate, with respect to which the cylinder drum is rotatable. It is desirable for such a micropump to have a small displacement combined with a long service life and in which the displacement or delivery volume can be achieved with great accuracy. For that purpose, at least two cylinders are provided, of which at least one is in the form of a working cylinder which has an associated working piston, while at least one other cylinder is in the form of a balance cylinder and has an associated balance piston.

Abstract: A device for adjusting the displacement of a fluid pump includes a swashplate supported for pivotal movement about a first axis, and an engine having first and second cylinders. A first piston is located in the first cylinder and secured to the swashplate at a first side of the first axis. A second piston is located in the second cylinder and secured to the swashplate at a second side of the first axis opposite the first side. A plate is secured to the swashplate for pivotal movement about the first axis and is supported for rotary oscillation relative to the swashplate about a second axis. A pump includes a third cylinder and a first plunger located in the third cylinder, secured to the plate for pivotal movement about the first axis and rotary oscillation about the second axis. The plunger displaces fluid from the third cylinder as the plunger reciprocates.

Abstract: A hydraulic motor is equipped with an output shaft (2), a cylinder (4) arranged around the output shaft and receiving a plurality of pistons (6) expanding with the fluid pressure, a diagonal plate (7) that contacts the plurality of the expanding pistons (6), thereby to exert rotational force to the cylinder (4), a brake disc (21) disposed outside the cylinder (4) to rotate together therewith, a motor casing (11, 12) receiving the cylinder (4) and the brake disc (21), a brake driving device (25) that presses an outer periphery of the brake disc (21) on an inner peripheral surface of the motor casing (11, 12) to brake the brake disc. A first chamber (14) and a second chamber (15) are defined in the motor casing (11, 12) by the brake disc (21) and a communicating passage (30) formed bypassing the brake disc (21) communicates the first chamber 814) with the second chamber (15).

Abstract: An improved compact design for a hydrostatic transmission having a hydraulic pump and hydraulic motor mounted on a center section in a housing, wherein the pump and motor are mounted at generally right angles to one another, and the longitudinal axis of the input shaft is located between a first and second parallel planes located at respective ends of the motor shaft and the longitudinal axis of the motor shaft is located between a third and fourth parallel planes located at respective ends of the pump shaft.

Abstract: A swash plate type hydraulic pump or motor comprises first and second swash plates which move reciprocally while opposing first and second pistons, so as to expand and contract a volume chamber according to rotation of a cylinder block. Drive pistons push on the swash plates from behind, causing the first and second swash plates to tilt, respectively. A tilt angle control valve controls the tilt angles of the swash plates by selectively increasing drive pressures that are guided to the drive pistons. A port plate is provided in a sliding portion between the first swash plate and the first piston. The port plate rotates integrally with the cylinder block and guides high and low pressure side hydraulic fluid, which flows through the supply and discharge ports provided in a sliding surface of the first swash plate, to the volume chamber via an inner portion of each first piston.

Abstract: A hinge mechanism for a variable displacement swash plate type compressor including an arm extending from a rotor and a pair of arms extending from a swash plate hub, wherein a pair of shoes are interposed between the arm of the rotor and each of the arms of the swash plate hub to facilitate a tilting of a swash plate disposed on the swash plate hub, the hinge mechanism militating against undesirable contact between the arms of the swash plate hub and the arm of the rotor.

Abstract: An operation mechanism for a variable displacement hydraulic pump. The hydraulic pump is disposed in a housing filled with fluid. A capacity regulating member is provided on the hydraulic pump in the housing for changing the discharge amount of the hydraulic pump. An operation member is operationally connected to the capacity regulating member. The operation member is to be manipulated outside the housing. A resistive device is interposed between the operation member and the capacity regulating member for making the motion of the capacity regulating member slow. The resistive device is an assembly unit comprising a casing, a piston slidably disposed in the casing, and fluid filled in the casing. The casing is fitted into the hole provided in the housing.

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 hydraulic pump includes a housing, at least two pistons mounted to the housing to rotate relative to the housing, and a transition arm coupled to each of the pistons to rotate therewith. The transition arm is set at a predetermined angle relative to a longitudinal axis of the pump. An adjustment mechanism sets the transition arm at the predetermined angle. A cylinder is mounted within the housing to rotate relative to the housing and defines pump cavities for receiving the pistons. A face valve defines inlet and outlet channels in fluid communication with the pump cavities. An apparatus for varying the output volume of a piston assembly includes at least two pistons, a transition arm coupled to each of the at least two pistons, and a rotatable member. The transition arm includes a nose pin, and the rotatable member is coupled to the transition arm nose pin.

Abstract: A compressor, in particular for air conditioning systems in motor vehicles, having a housing, a housing sealing cover, a drive shaft with bearings and a drive device for pistons that are displaced back and forth. The drive device transfers the rotational displacement of the drive shaft into the back-and-forth displacement of the pistons. The compressor also includes a cylinder block, in which the pistons that are displaced back and forth take in and compress coolant, a valve device, in addition to a valve plate with intake and discharge valves comprising intake and discharge chambers for an intake pressure zone and a discharge pressure zone. A cylinder head may be a separate element from the housing, in pot-shaped form, or the housing sealing cover. The intake and discharge chambers, the valve device, and the cylinder block may be situated in the closed side of the pot-shaped housing.

Abstract: In a swash-plate compressor having a shoe slidably coupling a coupling portion of a piston to a swash plate, the coupling portion has a spherical contact surface and the shoe has a spherical surface slidable along the contact surface. At least one of the contact surface and the spherical surface has an oxide film retaining a number of self-lubricating particles. The swash plate is attached to a drive shaft which is rotatable. The piston performs reciprocal movement by the rotation of the swash plate.

Abstract: An axle driving system which houses in a housing thereof a hydrostatic transmission, axles, and a driving gear train for connecting output means of the hydraulic transmission and axles, so as to transmit power from a driving source to the hydrostatic transmission and to change the speed, thereby driving the axles. A first chamber therein contains the hydrostatic transmission and a second chamber therein contains the driving gear train. Both the first and second chambers are independent of each other so as to prevent a foreign object, such as iron powder produced in the driving gear train, from entering the hydrostatic transmission. The system includes an L-like-shaped center section on which the hydrostatic transmission is offset such that an imaginary plane which includes a motor mounting surface passes in proximity to the axis of a pump shaft. The pump shaft is disposed perpendicular to the axles. The motor shaft is disposed in parallel thereto.

Abstract: A lubricating structure in a fixed displacement piston type compressor has a housing, a rotary shaft, a cam, a piston, a rotary valve and a rotary body. The housing defines a cam chamber, cylinder bores and a suction pressure region. The rotary shaft is rotatably supported by the housing. The cam is located in the cam chamber and is connected to the rotary shaft. The piston is located in each of the cylinder bores and engages the cam to reciprocate with rotation of the rotary shaft through the cam. The rotary valve connected to the rotary shaft includes an introducing passage and a supply passage that interconnects the introducing passage and the suction pressure region. The introducing passage introduces fluid into the cylinder bores through the supply passage. The rotary body connected to the rotary shaft includes a communication passage that interconnects the cam chamber and the suction pressure region.

Abstract: An object of the present invention is to provide a sliding member which can slide for a longer period of time even in a dry state. In the present invention, sliding layers 3 are provided on the surfaces of a base material 2, and the sliding layer 3 contains polybenzimidazole (PBI) and 1 to 70 vol % of a solid lubricant. Since PBI, which is a thermoplastic resin, has higher heat resistance and also has higher material strength than PAI, PI, and EP, which are the conventionally used thermosetting resins, the wear resistance and the anti-seizure property can be improved and a decrease in material strength caused by high-temperature atmosphere, heat generation at the time of sliding, etc. can be restrained. Furthermore, the initial conformability can be improved because of high elongation percentage. Also, since the sliding layer contains the solid lubricant, the coefficient of friction can be decreased, and hence the anti-seizure property can be enhanced.

Abstract: A control mechanism for a hydraulic drive apparatus such as a transaxle having a hydraulic pump and moveable swash plate mounted in a housing including a control arm for moving the swash plate between forward and reverse positions and a unidirectional return to neutral mechanism for biasing and returning the swash plate to a neutral position when the control arm is in one of the reverse or forward positions but not from the other position.

Abstract: An operation mechanism for a variable displacement hydraulic pump. The hydraulic pump is disposed in a housing filled with fluid. A capacity regulating member is provided on the hydraulic pump in the housing for changing the discharge amount of the hydraulic pump. An operation member is operationally connected to the capacity regulating member. The operation member is to be manipulated outside the housing. A resistive device is interposed between the operation member and the capacity regulating member for making the motion of the capacity regulating member slow. The resistive device is an assembly unit comprising a casing, a piston slidably disposed in the casing, and fluid filled in the casing. The casing is fitted into the hole provided in the housing.

Abstract: In a hydrostatic device using an axial piston pump, a return plate is mounted so that it contacts the movable swash plate of the hydrostatic transmission. The plate is biased by a spring-type mechanism to force the swash plate to return to neutral, and the set position of the plate may be externally adjusted. A bias arm comprising a generally U-shaped member having spring mounted on either leg thereof may be engaged to the return plate.

Abstract: An arrangement structure of a swash plate hydraulic pump which can be used in a wide range of construction equipment and industrial vehicles and is small in size, simple in structure, and inexpensive is provided. For this purpose, an arrangement structure of a swash plate hydraulic pump (1) comprises a driving source (3) and a plurality of swash plate hydraulic pumps (4, 8) which are connected to the driving source and discharge pressurized oil, and the plurality of swash plate hydraulic pumps include at least one swash plate hydraulic pump (8) of the second and subsequent swash plate hydraulic pumps which has a driving shaft (9) provided on a plane almost perpendicular to a driving shaft (6) of the first swash plate hydraulic pump (4) coupled to the driving source.

Abstract: According to the invention, a compressor having a threaded screw connection portion formed directly on a fitting portion of the housing is provided. Since no through bolt or the like for connecting two-parts of the housing is used, the diameter of the housing can be reduced. However, in a case that a suction port and discharge port do not align with an external mounting structure, a mounting means able to slide on the housing and adjust the positions of mounting brackets at least in the direction of rotation is added.

Abstract: A hydraulic motor includes a motor cylinder having motor plunger holes, motor plungers disposed in the respective plunger holes, a motor rolling member which is tilted and rolled to change the angle of a swash plate, and a motor servo mechanism for tilting and rolling the motor rolling member. The motor servo mechanism includes a screw shaft with male screw, a ball nut having a ball thread mated to the male screw and connected to an arm portion of the motor rolling member, a swash plate control motor, and a stopper mounted to the end of the screw shaft. The stopper includes a ring portion adjacent to the end of the male screw at a limit position of the ball nut and a flange portion which contacts the side face of the ball nut at the limit position.

Abstract: In a wobble plate piston-drive mechanism, the inclination of the ring-shaped wobble plate is adjustable through an articulated connection of the wobble plate to the shaft by means of an axially movable guiding device and a driver arm that reaches into an engagement cavity of the wobble plate at a radial distance from the shaft to transmit the driving force from the shaft to the wobble plate. The driver arm head and/or the engagement cavity are shaped so that the force-transmitting contact between the driver arm head and the annular wobble plate is moved away from the area where the engagement cavity has its minimum wall thickness. This prevents or reduces deformation of the gliding surface of the wobble plate and thus makes the mechanism run more smoothly.

Abstract: In a piston for a compressor, the piston comprises a stem by which the piston may be guided in the housing in an axially displaceable manner, and a force introducing section where an outer drive force can be introduced into the piston. The piston head, the piston skirt and the force introducing section are successively arranged in the direction of the piston axis. The piston head, the piston skirt and the force introducing section are produced as a single element of graphite or a synthetic material, and the piston skirt comprises a solid strut structure and a guide section, the cross-sectional area of the strut structure being smaller than the surface of the piston head. The piston consists of a non-organic, non-metallic material having an average thermal expansion of less than 7×106/° C. in the temperature range of 0° C. to 200° C.

Abstract: A metering pump includes an actuating mechanism, and a plurality of piston cylinders coupled to the actuating mechanism. A first of the cylinders has a working volume that differs from a second of the cylinders. The actuating member is centrally located and the cylinders are arranged radially about the actuating mechanism. The working volume of the cylinders can be varied by adjusting the spacing of the cylinders from the actuating mechanism, thus varying the stroke of pistons housed within the cylinders, and/or by providing the cylinders with different inner diameters. A method of metering fluids includes independently adjusting stroke of a plurality of pistons to adjust the volume of metered fluid, and selecting different cylinder diameters to adjust the volume of metered fluid.

Abstract: The subject invention provides a pivot assembly for rotatably connecting a rotor to a swash plate in a variable displacement compressor. The rotor and swash plate each having pivot arms supporting pivot pins. A hinge is mounted to both of the pivot pins for operatively connecting the rotor to the swash plate. The hinge includes a first mounting portion receiving one of the pins and a second mounting portion receiving the other pin with a central planar region disposed between the first and second mounting portions. A tab extends from the central planar region toward each of the first and second mounting portions to engage the pins and fixedly secure the pins within their respective mounting portions. The pins therefore remain mounted to the hinge during an operation of the variable displacement compressor.

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 having a symmetric end cap is disclosed. The end cap is attachable in a first position or a second position wherein the second position is rotated relative to the housing. A trunnion arm extends in a first direction and a system port opens in a first orientation when the housing is connected to the end cap in a first position. The end cap includes structure such that the housing may be connected in a second position so that the trunnion arm extends in a second direction while maintaining the system port opening in the first orientation. The end cap may be provided with a symmetric porting system. A control device for affecting movement of the swashplate is disclosed. Methods of locking the swashplate into a predetermined position are also taught.

Abstract: A swash plate containment assembly for a compressor is disclosed generally comprising a housing, a drive shaft, a swash plate mounted on the drive shaft, and a gimbal arm connected to the housing and swash plate via rotatable joints. In certain embodiments, the joints are located approximately ninety degrees from each other. In some embodiments, the joints comprise a roller bearing and journal coupled thereto.