Abstract: A compressor, which is adapted for use in an air-conditioning system of a motor vehicle, having a housing (2) and a compressor unit (1) arranged in the housing (2) for drawing in and compressing a coolant. The structural size of the compressor is reduced, while sufficient compressor capacity is ensured, as a result of manufacturing the housing (2) from a high-strength material and using a gas that has a high density even in the drawn-in state as the coolant.

Abstract: A piston-type compressor has seven cylinder bores formed in a cylinder block which is formed in a compressor housing. A piston is slidably disposed within each of the cylinder bores. Each of the pistons includes a cylindrical main body and an engaging portion axially extending from the cylindrical body. A drive shaft is rotatably supported in the cylinder block. A bearing couples the plate to each of the pistons, so that the pistons reciprocate within the cylinder bores upon rotation of the plate which is tiltably connected to the drive shaft. A recessed portion is formed in an interior of the cylindrical body of each piston so that the cylindrical body forms a C-shaped cross-section perpendicular to longitudinal axis of the piston. Therefore, the configuration obtains lightweight pistons while simultaneously maintaining the efficiency of the compressor.

Abstract: A hydraulic axial pump/motor comprises a plurality of revolving as well as reciprocating pistons, operatively associated with a stationary port plate. The port plate comprises at least a first, elongated, arcuate suction port and at least a second elongated, arcuate discharge port, divided by a bringing portion extending between the downstream side of the suction port and the upstream side of the discharge port. A tortuous passage of a non-uniform cross-section is formed in the bridging portion, allowing the by-passing of the fluid first in a direction towards the downstream side of the suction port and then towards and into the upstream side of the discharge port.

Abstract: A variable displacement type compressor having a piston accommodated in a cylinder bore, a swash plate accommodated in a crank chamber for reciprocating the piston and a drive shaft for tiltably and rotatably supporting the swash plate. The swash plate includes projections that extend toward a thrust bearing and have outer surfaces that contact the thrust bearing. A shaft hole within which the drive shaft is located between the projections. The shaft hole has an opening that opens adjacent to the projections. A recess is formed at the end of the shaft hole adjacent to the projections. A hardening method is performed on the wall of the through hole and on the outer surfaces of the projections to improve wear resistance. The hardening method prevents overheating of localized areas of the swash plate.

Abstract: A variable displacement swash plate type compressor including a sleeve member (18) placed on a drive shaft (6) between a through-bore (20) formed in a swash plate (11) and a drive shaft (6) so as to move along the axis of the drive shaft (6) in response to a movement of the swash plate (11) for changing its angle of inclination.

Abstract: In a swash-plate compressor wherein a piston (23 ) is connected through a connection mechanism to a swash plate (34) supported on a drive shaft (26), the swash plate is rotatable relative to the drive shaft around a predetermined axis extending in a given direction. The piston has a drive end portion (36) having a concave surface (37) defining a recessed portion. The swash plate is provided with a flat portion (38) loosely inserted in the recessed portion. Between the concave surface and said flat portion in the given direction, a sliding member (38a or 38b) is held to be slidable along the concave surface and the flat portion. A combination of the drive end portion, the flat portion, and the sliding member is referred to as the connection mechanism.

Abstract: A hydraulic slipper includes a slipper body having first and second ends and a central portion therebetween. The first end terminates in a spherical-shaped head. The second end terminates in a round base portion with a hub protruding outwardly therefrom in the direction away from the head. The hub terminates in a planar surface and has a diameter less than the diameter of the round base portion. The slipper includes a washer element having a center opening extending around the hub and having first and second opposite planar surfaces. The first surface engages the base portion, and the second surface extends beyond the planar surface of the hub to create a running face for the slipper. The washer element can be a bi-metal ring formed of steel and bronze.

Abstract: A fluid powered rotary actuator (10) having a stator (13) and a rotor (15) journalled with limited rotary motion within the stator includes at least one arcuate chamber defined between the rotor and stator and has an angularly movable vane (16) fixed to the rotor. There is a seal member (21, 23) at the vane for slidingly sealing a cylindrical sidewall surface of the stator thereby subdividing the arcuate chamber into two variable volume subchambers (25, 29; 27, 31). Pressurized fluid is ported selectively to one of the subchambers while a fluid egress path for fluid from the other of the subchambers allows the rotor to move angularly within the stator. There is a fail-safe aperture (22) in the cylindrical stator surface in a region traversed by the seal member and for conveying fluid from a selected one of the subchambers, as determined by the position of the vane, and a fail safe valve (24) coupled to and normally blocking the egress of fluid from a subchamber through the aperture (22).

Abstract: A variable capacity swash-plate-type refrigerant compressor incorporating therein single-headed pistons reciprocating in the cylinder bores to compress refrigerant gas, a drive shaft rotatably supported and driven by an external drive source, a swash-plate element mounted around the drive shaft and rotated by the drive shaft so that the rotation of the swash-plate element causing the reciprocation of the single-headed pistons, and a hinge mechanism arranged between the drive shaft and the swash-plate element to permit the swash-plate element to change its angle of inclination with respect to the axis of rotation of the drive shaft to thereby adjustably change the delivery capacity of the compressor, the swash-plate element being constituted by a swash-plate-body member made of an aluminum alloy material and functioning as a sliding contact member cooperating with the single-headed pistons via shoes, and a guide-bracket member made of an iron based material and functioning as a hinge mechanism forming member.

Abstract: A rotationally pivotal motion controller pivotally interconnects two adjoining elements and controls the pivotal motion of a first of the two adjoining elements with respect to a second of the two adjoining elements. The rotationally pivotal motion controller comprises a housing having a wall which defines an axial cylindrical bore through the housing. The wall is adapted for attachment to a first of the two adjoining elements and the wall also has a longitudinal aperture therethrough which communicates with the bore. A hub assembly comprises a hub which is at least partially disposed within the cylindrical bore of the housing and is axially rotatable therein. The hub has a substantially central cylindrical core and at least one lobe extending radially from the core. At least one end cap is affixed to one end of the hub to retain the hub in a fixed, fluidically sealed, axial relationship within the housing. The hub and the housing together define at least one fluid retention cavity.

Abstract: A control system, method and apparatus are provided in which a rotatable wedge portion which is solidly mounted on a rotatable base engages piston and cylinder assemblies as the base rotates. In another embodiment the rotatable base is not affixed to the shaft, but instead is allowed to rotate with respect to the shaft, while the shaft is affixed to the cylinder and piston, which rotate with the shaft. The wedge is rotatable through various positions relative to the base, thus providing an adjustable tilt angle and different strokes for the pistons. In another embodiment, the single wedge is replaced by a double wedge assembly.

Abstract: There is provided a variable capacity swash plate compressor having a construction which is capable of lubricating sliding contact portions of a retainer and a retainer support plate to thereby reduce abrasion of the two component parts of the compressor and prevent noises from being produced from them. The variable capacity swash plate compressor has a retainer mounted on its swash plate in a relatively rotatable manner with respect to the swash plate for supporting a plurality of shoes, and an annular retainer support plate for supporting the retainer in a state held in surface contact with one face of the retainer. In the variable capacity swash plate compressor, the retainer support plate is formed with a cut-away portion which is cut away therefrom, thereby increasing an exposed area of the one face of the retainer.

Abstract: A hydraulic drive unit of a press machine and a swash plate type variable capacity axial piston pump to use a hydraulic drive unit. Discharge of the pump and the direction of the hydraulic pressure can be controlled at high speed, and the direction of the hydraulic pressure and the timing of the discharge can coincide. The selector device 12 includes spool valves in parallel is used in place of a servo valve. An electric motor 30 for driving the pump and cam of the axial piston pump 11 and an electric motor 47 for driving the selector cam of the selector device 12 are controlled cooperatively by commands from the numerical control device 14. Two spools 44a, 44b of the selector device 12 performs changeover actuation alternately. Synchronous control of the discharge of the axial piston pump 11 and the flowing direction change of working fluid to the hydraulic pressure cylinder 1 are done, so that the piston 1a of the hydraulic pressure cylinder 1 is made to move up and down.

Abstract: A cylinder sleeve is composed of multiple identical interlocking sleeve elements. Each sleeve element has a circular cylindrical portion and an integral circular arc portion tangent to the cylindrical portion. The circular arc portion has a boss on one end and an offset finger on the other which mates with the boss of an adjacent sleeve element to fix the adjacent sleeve elements together radially.

Abstract: An axial piston machine comprises first and second members arranged so that one of the first and second members is swingable relative to the other to provide relative swinging motion, a plurality of pistons inserted in a plurality of cylinders formed in the second member, respectively, the pistons being mechanically engaged with the first member so that the relative swinging motion reciprocates the plurality of pistons in the cylinders, and a swinging mechanism for swinging the above-mentioned one of the first and second members relative to the other, and the axial piston machine is characterized in that the first and second members have spherical portions providing a coupling portion binding one of the first and second members to a spherical point of the other to be universally rotatable about the point, and the above-mentioned swinging mechanism comprises a relative revolving mechanism for revolving at least one of the first and second members relative to the other to provide a relative swinging motion betw

Abstract: A variable capacity wobble plate compressor includes a first spring, fitted on a drive shaft between a hinge ball axially slidably fitted on the drive shaft and a thrust flange rigidly fitted on the drive shaft, for urging the hinge ball toward a cylinder block, and a second spring fitted on the drive shaft between the hinge ball and the cylinder block for urging the hinge ball toward the thrust flange. As the hinge ball is moved toward the thrust flange, a linkage connecting a drive hub slidably mounted on the hinge ball a causes an inclination of the drive hub to be increased to increase capacity of the compressor, and as the hinge ball is moved toward the cylinder block, the linkage causes the inclination of the drive hub to be decreased to decrease the capacity of the compressor. A first stopper blocks the hinge ball from moving toward the thrust flange in excess of a predetermined amount, to thereby restrict an increase in the inclination of the drive hub and set the maximum capacity of the compressor.

Abstract: There is disclosed a workhead for timber processing, the workhead having a main body and a jaw assembly for grappling timber. The jaw assembly includes first and second cooperating pairs of jaw arms that are pivotally mounted to the main body. The first of the cooperating pairs of jaw arms provides cutting blades for delimbing. The workhead further includes a feed roller assembly for translating a felled tree through the cutting blades. First and second feed rollers of the feed roller assembly are associated with the jaw arms of the second cooperating pair of arms of the jaw assembly. A third feed roller is provided on the main body for pivotal movement relative to the main body. The feed rollers also effect compression debarking of the felled tree as it is translated through the cutting blades. Each roller has projecting engaging bars which extend in a generally helical configuration along the outer surface of the roller and between its opposed terminal ends.

Abstract: A swash plate compressor includes a plurality of shoes each arranged on a sliding surface of a swash plate, for relative rotation with respect to a circumference of the swash plate as the drive shaft rotates, a retainer mounted on the swash plate in a relatively rotatable manner with respect to the swash plate, for retaining the shoes, and a retainer support member rigidly fitted on the swash plate, for slidably supporting the retainer. The swash plate compressor has a sliding plate interposed between the retainer and the retainer support member in a slidable manner with respect to both of the retainer and the retainer support member.

Abstract: A variable capacity wobble plate compressor includes a drive shaft, a rotating member rigidly fitted on the drive shaft for rotation in unison with the drive shaft, a tilting rotating member mounted on the drive shaft in a slidable manner, and a pair of link members connecting the rotating member and the tilting rotating member to each other. The rotating member has one radial end portion thereof formed with a pair of link member-holding portions extending in parallel with each other. The pair of link members has one ends thereof pivotally connected to the pair of link member-holding portions by a first connecting member, and other ends thereof connected to the tilting rotating member by a second connecting member.

Abstract: A compressor has pistons slidably housed in cylinder bores. Respective shoes slide against each of the pistons and a swash plate or cam to convert rotation of the swash plate to reciprocation of the pistons. Each piston has a recess for slidably receiving the shoe. A friction reducing layer containing tin as a major component is formed between the shoe and the piston. Additionally, a tin-based layer may be formed between the shoe and the swash plate.

Abstract: A variable capacity swash plate compressor has a retainer mounted on its swash plate in a relatively rotatable manner with respect to the swash plate for supporting a plurality of shoes, and an annular retainer support plate for supporting the retainer in a state held in surface contact with one face of the retainer. The retainer support plate has an annular recess formed on a cylinder block-side face thereof, for holding lubricating oil therein, and a lubricating oil supply hole formed through a compressing piston-side portion thereof which does not receive tensile forces from pistons in the suction stroke, for supplying the lubricating oil from the annular recess to the one face of the retainer therethrough.

Abstract: A swash plate of a variable capacity swash plate compressor has a front-side sliding surface and a rear-side sliding surface. Pairs of substantially hemispherical shoes each perform relative rotation on the front-side and rear-side sliding surfaces of the swash plate, respectively, with respect to the circumference of the swash plate as the drive shaft rotates. A plurality of pistons each have one end thereof formed therein with a pair of concave support portions for each slidably supporting the shoe. At least one of the front-side and rear-slde sliding surfaces of the swash plate has a mounting recess formed at an outer peripheral portion thereof, the outer peripheral portion receiving no load which acts on the at least one of the front-side rear-side sliding surfaces of the swash plate. The mounting recess is used for assembling the each pair of the pairs of shoes with the swash plate and the pair of concave support portions at the one end of a corresponding one of the pistons.

Abstract: A front housing (20) has a shaft hole (210) and an oil path (20a) communicating with a crank chamber (15) and the shaft hole to lubricate a bearing supporting a drive shaft (3) and and a shaft seal contained in the shaft hole. A lubricating oil in the crank chamber (15) is scraped by the rotation of the drive shaft (3). An oil trap (19) is formed at one end of the oil path (20a) to effectively collect the lubricating oil which is supplied through the oil path (20a) to the shaft hole (210). The oil trap (19) is formed by a part of a first thrust race (201b) and an oil receiving groove (20g). The first thrust race (201b) has a plurality of finger portions (201d) bent towards a bottom surface of an annular groove (204) formed in an internal wall surface of the front housing (20). The annular groove (204) has a plurality of fitting holes (20h) for receiving the finger portions (201d) therein in one-to-one correspondence.

Abstract: A piston-type fluid displacement apparatus includes several pistons, each of which is slidably disposed within one of several cylinder bores. A plating layer, which includes a self-lubricating material, is coated on a peripheral surface of each piston. At least one annular groove is formed on a periphery surface of each piston, and, at least one piston ring is disposed within the annular groove of each piston for sealing a gap between the piston and the cylinder bore. Thereby, the piston-type fluid displacement apparatus may be simply manufactured at a reduced assembly cost while simultaneously prolonging the life of the piston rings and while reducing or eliminating a decrease in compression efficiency during the operating life of the piston-type fluid displacement apparatus.

Abstract: A variable capacity swash plate compressor includes a plurality of pistons slidably received in a plurality of cylinder bores, respectively, a rotating member rigidly fitted on the drive shaft, for rotation in unison with the drive shaft, a swash plate mounted on the drive shaft in a manner tilted with respect to an imaginary plane perpendicular to the drive shaft and axially slidable along the drive shaft, and a linkage interposed between the rotating member and the swash plate, for tiltably connecting the swash plate to the rotating member to cause the swash plate to rotate in unison with the rotating member. The link member is offset by a predetermined amount from a boundary between a compressing piston-side area which receives compression reaction forces from ones of the pistons during the compression stroke and a suction piston-side area which receives tensile reaction forces from ones of the pistons during the suction stroke, toward the compressing piston-side area.

Abstract: The invention relates to an axial piston machine of skew plate construction, the pistons (7, 8) of which are supported on a sliding surface (11), acting as a skew plate, of a cradle (12) pivotable about an axis (33). The pivoting angle of the cradle (12) can be adjusted by means of an adjusting device coupled to the cradle (12) via a coupling device (20). According to the invention, the coupling device (20) permits both coupling to a transverse adjustment (30) carrying out a translational adjustment movement and to a rotary adjustment carrying out a rotational adjustment movement. To this end, the coupling device (20) has a bolt element (34) located eccentrically offset in relation to the axis (33), which bolt element cooperates with a sliding element (32) for coupling to the translational adjustment movement and with an eccentric component connected to a rotary shaft (50) for the coupling of the rotational adjustment movement.

Abstract: A hydrostatic axial piston machine with a swash plate achieves a high power with a compact and simple construction. Two cylinder drums are at some axial distance from one another and are in synchronous rotation. Each drum contains a group of concentric cylindrical borings, between which, and at an angle with respect to the axis of rotation of the axial piston machine there is a rotationally locked circular ring-shaped eccentric disc. The pistons are guided against the disc so that they can move longitudinally in the cylinder bores. Each piston consists of two piston segments having the same diameter oriented coaxially to one another and at some distance from one another. The segments are inserted in cylinder bores which are located opposite one another and are connected to one another by a bridge segment. Two support bodies, one on either side of the eccentric disc, are provided for movement on the eccentric disc along a track.

Abstract: A swash plate type compressor having a cylinder block with cylinder bores disposed parallel to the axis of the cylinder block. A rotary shaft rotatably mounted within the cylinder block carries an aluminum swash plate. The swash plate is fixed in the rotary shaft and has two facial surfaces and an end surface. The swash plate has a coating preferably between 0.8 to 2.5 microns, of a tin/cobalt coating of at least 0.2 wt% cobalt and the balance being tin. A piston reciprocally fitted within the cylinder bore contains shoes which slideably intervene between the piston and the swash plate facial surfaces and reciprocate the piston and the swash plate facial surfaces and reciprocate the pistons by rotation of the swash plate. The coating on the swash plate permits the use of low silicon alloy aluminum without the need of metal plating or high finish polishing.

Abstract: The fluid expander includes a housing, a drive shaft mounted for rotation within the housing, a piston-cylinder assembly including a cylinder and a piston disposed within the cylinder for converting energy from a working fluid to rotational energy output via a drive shaft. Various adjustment assemblies are provided for adjusting speed, torque, stroke length, and thermodynamic cycles of the device. The fluid expander assembly can be used with external combustion systems, with solar or geothermal energy systems, or with internal combustion systems.

Abstract: In a shoe 5 for a swash plate compressor, the conical tapered surface 13 is formed between the spherical surface 10 and the rounded edge 14 to converge toward the spherical surface 10 inside an imaginary spherical surface 15 including the spherical surface 10. The conical tapered surface 13 forms a relatively large arcuate gap 23 between the hemispherical concavity 7 and the conical tapered surface 13. The arcuate gap 23 serves to reserve necessary amount of lubricant oil which may be supplied to sliding portions between the spherical surface 10 of the convex surface 11 and hemispherical concavity 7 of the piston 2. In addition, upon manufacture of the shoe 5, it can easily be removed from a metallic mold 52 due to existence of the arcuate gap 23 which prevents tight fit of the shoe 5 in the mold 52.

Abstract: A swash plate assembly for use in connection with a hydrostatic transmission. The swash plate assembly comprises a thrust bearing and a swash plate formed as a net shaped part from a plastic material adapted to carry the thrust bearing wherein the swash plate has an elongated aperture for allowing a shaft to pass therethrough and a plurality of acoustical cavities formed in the underside thereof generally arranged around the elongated aperture and proximate to the thrust bearing.

Abstract: A compressor (1) with at least one piston (9) movable in a cylinder (10), a drive shaft (2) and a wobble plate arrangement (4, 5) between piston (9) and drive shaft (2), having an inclined plate (4) with variable inclination angle, and with a spring arrangement (17; 41 to 43), acting on the wobble plate arrangement in the direction of a minimum displacement. Such a compressor should also be able to operate at higher pressures without increasing its size, e.g. to enable the use of CO.sub.2 as refrigerant. For this purpose the spring arrangement (17; 41 to 43) acts on the wobble plate arrangement (4, 5) in the area of the radial edge.

Abstract: A pressure transformer is provided having a housing, with a rotating group disposed therein, an adjustable port plate is disposed between a barrel of the rotating group and a head portion of the housing. The barrel has a plurality of pistons slideably disposed in cylinders defined in the barrel. The cylinders each define a cylinder port that is in intimate contact with the port plate. Each cylinder port has a predetermined circumferential length. The port plate has three arcuate slots defined therein and spaced from one another along a predetermined circumference. Each arcuate slot has a leading edge and a trailing edge. Likewise each of the cylinder ports has a leading edge and a trailing edge. The shape and orientation of the leading edges and trailing edges of the cylinder ports and the arcuate slots are the same. The circumferential length of the space between adjacent ones of the arcuate slots is less than the circumferential length of the respective cylinder ports.

Abstract: A swash plate which is made of an iron-based or aluminum-based material and is used in a single-side compression type swash-plate compressor. A flame-sprayed copper-based alloy layer is formed on at least a sliding surface with a first shoe in a compression space side. The flame-sprayed copper-based alloy layer contains in total, by weight percentage, not less than 0.5% and not more than 50% of one or more kinds selected from not more than 40% of lead, not more than 30% of tin, not more than 0.5% of phosphorus, not more than 15% of aluminum, not more than 10% of silver, not more than 5% of silicon, not more than 5% of manganese, not more than 5% of chromium, not more than 20% of nickel, and not more than 30% of zinc and the balance essentially copper and impurities. Electrolytic plating, electroless plating, lubricant coating, phophatizing or hardening is applied on at least a second sliding surface with a second shoe in the side opposite to the compression space.

Abstract: A hydraulic drive unit of a press machine and a swash plate type variable capacity axial piston pump to use for a hydraulic drive unit. Discharge of the pump and the direction of the hydraulic pressure can be controlled at high speed, and the direction of the hydraulic pressure and the timing of the discharge can coincide. The selector device 12 that includes spool valves in parallel is used in place of a servo valve. An electric motor 30 for driving the pump and cam of the axial piston pump 11 and an electric motor 47 for driving the selector cam of the selector device 12 are controlled cooperatively by commands from the numerical control device 14. Two spools 44a, 44b of the selector device 12 perform changeover actuation alternately. Synchronous control of the discharge of the axial piston pump 11 and the flowing direction change of working fluid to the hydraulic pressure cylinder 1 are done, so that the piston 1a of the hydraulic pressure cylinder 1 is made to move up and down.

Abstract: A variable displacement compressor includes an inclining swash plate connected to a drive shaft. A rotor rotates integrally with the drive shaft. A guiding mechanism is provided between the swash plate and the rotor to guide the inclination of tho swash plate between a minimum inclination position and a maximum inclination position and thus change the stroke of the piston. An abutment is provided to restrict the inclination of the swash plate. In another embodiment, a cap included in the guiding mechanism determines the maximum inclination position of the swash plate. In one embodiment, the maximum inclination position is determined by the length of a spring arranged between the swash plate and the rotor. In another embodiment, a spacer is arranged between the swash plate and the rotor. The thickness of the spacer determines the maximum inclination position. The maximum displacement of the compressor can be changed by changing only one part.

Abstract: The invention relates to an axial piston pump with at least one pump element, which includes a piston disposed in a housing, with a drive shaft upon which a swash plate for driving the piston is disposed. The swash plate is non-rotatably fixed, but can pivot around a swash plate pivot axis which extends perpendicular to the longitudinal drive shaft axis (A), and with a device for adjusting a pivot angle between the drive shaft and the swash plate. In order to be able to adjust the oblique position of the swash plate in a simple manner, even during pump operation, it is provided that the device for adjusting the pivot angle of the swash plate has a displacing device disposed in a stationary manner on the housing.

Abstract: A variable displacement axial piston pump (11) having a tiltable swashplate (33) to vary pump displacement by a manual input lever (43). The pump includes a neutral centering device (45) in which a cam member (57) is fixed to the end of one trunnion member (35). The cam member (57) defines three cam surfaces (65), each having a minimum displacement portion (67) and at least one maximum displacement portion (69). In engagement with each of the cam surfaces (65) is a follower element (79) supported by a cam follower holder (73), both of which are biased by a set of Belleville washers (75), toward the cam member (57). The present invention provides a neutral centering device which is balanced and simple to assemble, not requiring any special fixtures or holders for preloading a biasing spring, but which is able to provide a substantially constant return torque.

Abstract: A guide member of a wobble plate compressor is slidably mounted in an inner wall surface of a housing of the wobble plate compressor. The guide member comprises a guide part having a U-shaped cross-section and defining a linear guide groove therein into which is slidably inserted a rotation-preventing member rigidly mounted on the wobble plate, and a pair of half cylinder shaped sliding parts mounted on opposite sides of the guide part for sliding in the inner wall surface of the housing. The inner surface of the guide member is hardened by surface treatment.

Abstract: A hydrostatic transmission comprising a hydraulic pump and a hydraulic motor fluidly connected with each other through a closed fluid circuit. Pistons press against a control arm connected with a movable swash plate of the hydraulic pump and generate a friction force when the movable swash plate, which has been rotated slantwise, automatically returns toward the neutral position by a neutral return spring. The movable swash plate gradually returns to the neutral position by pressure of the piston. A discharging oil hole is open at the utmost end of each of the pistons for draining a portion of operating oil which operates the piston in the closed fluid circuit to the interior of a housing. Grooves are formed along a surface of the control arm abutting against the pistons.

Abstract: This invention pertains to a single-piece unidirectional tapered land thrust bearing cluster for use in high-pressure positive-displacement swashplate piston pumps and the like. The bearing cluster has a plurality of identical bearing pads integral to the bearing cluster. Each bearing pad includes a tapered section, a flat section and a fluid communicating slot integral therewith. During operation of the pump the swashplate camming surface rotates relative to the bearing cluster which develops a pressurized load-carrying hydrodynamic film of decreasing thickness and increasing strength between a back plate of the rotating swashplate and the bearing cluster.

Abstract: In a piston pump/motor of swash plate type which comprises: a cylinder block disposed in a casing to be rotatable jointly with a shaft therein; a plurality of pistons slidably inserted in the cylinder block parallel to the shaft; and a swash plate swingably attached to the casing for guiding the plurality of pistons on a front surface thereof and changing a displacement of each of the pistons by changing an inclination thereof, there is provided a swash plate angle changing apparatus in which the swash plate has a rear surface formed with a first contact surface and a second contact surface which make an angle between them. The casing has a swash plate support surface which is perpendicular to the shaft and with which the first contact surface and the second contact surface are each adapted to contact.

Abstract: A hydrostatic transmission is housed in a housing so as to drive axles of a moving vehicle. A speed adjusting means for changing the angle of slant of a movable swash plate of a hydraulic pump portion of a hydrostatic transmission is provided and is held in an optional position by friction members and biasing means disposed inside or outside of the housing.

Abstract: A method and apparatus for braking a rotating element including a reversible eccentric ring or axial piston pump which may be selectably operatively connected to a rotating element. When either pump is configured to compress ambient fluid into a reservoir, the compressive resistance is transmitted to the rotating element, braking it. When either pump is configured to expand fluid from the reservoir, the resultant torque generated is transmitted to the rotating element, driving it. The invention provides mechanisms for rapidly configuring either pump to compress or expand fluid, and for adjusting pump displacement, respecting a user's demand.

Abstract: An axial piston pump assembly includes a housing having an outer wall defining a generally cylindrical interior and an end wall. A drive shaft extends through the end wall is rotatably mounted in the housing for rotation on the axis of the cylindrical interior, and the rotor is attached to the drive shaft for rotation therewith. A plurality of circumferentially spaced, axially disposed cylinders is positioned in the rotor, and a series of axially reciprocable pistons is disposed in the cylinders. A swashplate surrounds the drive shaft and is mounted in the housing for tilting movement on a tilt axis transverse to the drive shaft axis. A planar reaction surface on the swashplate is engaged by the outer ends of the pistons. A biasing arrangement is provided for urging the piston ends into engagement with the reaction surface, and a control arrangement is supplied for tilting the swashplate on its axis to maintain the reaction surface angularly disposed with respect to the axis of the drive shaft.

Abstract: A hydraulic pump is disclosed having an adjusting member for varying yoke angle. The present adjusting member includes a control piston for displacing the yoke so as to define a desired yoke angle. A stop member is provided having threads and retained within the control piston. An adjusting screw for rotational motion is provided and includes an O-ring and a back up ring for sealing between the screw and the pump housing. The screw also includes a threaded portion for engaging the threads of the stop member. Rotation of the screw advances the threads while remaining stationary, displacing the control piston to limit the maximum inclination of the yoke.

Abstract: A reciprocating piston type compressor for compressing refrigerant gas for an automobile air conditioning system is provided with a cylinder block assembly which includes a plurality of cylinder bores, a swash plate chamber and an oiler channel which extends along the one of the end walls of the swash plate chamber. When the refrigerant gas, which flows rotationally in the swash plate chamber due the rotating swash plate, contacts the oiler channel, the lubricating oil mist, in the refrigerant gas flow in the swash plate chamber induced by the rotation of the swash plate, is separated from the refrigerant gas and the separated lubricating oil is introduced into the bearing means by the oiler channel.

Abstract: A hydraulic axial piston machine is disclosed, having a cylinder drum, which has at least one cylinder in which a piston is arranged to move back and forth, which piston bears by way of a slide shoe against a swash plate, wherein the cylinder drum and the swash plate are rotatable relative to one another, and a pressure plate, which holds the slide shoe in contact with the swash plate, is joined, articulated, to the cylinder drum by way of a ball-and-socket joint having a convexly spherical bearing surface. It is desirable for manufacture of such a machine to be simplified. To that end, the bearing surface is formed by a friction-reducing plastics material.

Abstract: A variable displacement swash plate type compressor has a coupling structure between a drive shaft and a swash plate in order to allow the swash plate to be movable along the drive shaft and inclinable relative to the same. The coupling structure comprises a bearing portion provided on the drive shaft to rotate therewith. The bearing portion includes first and second semicylindrical outer walls which are symmetrically arranged with respect to an axis of the drive shaft and first and second flat side walls which are symmetrically arranged with respect to the axis. Each of the first and second semicylindrical outer walls is perpendicular to each of the first and second flat side walls. The bearing portion further includes a rectangular center bore formed in a hub portion of the swash plate. The center bore is so sized and shaped as to intimately and slidably receive therein the bearing portion.

Abstract: Two synchronous hydraulic polyphase motor-generators with axial cylinders are connected by rigid or flexible pipes. One functions as a generator, the other as a motor to transmit torque and power. Sinusoidal piston motion is developed without the use of cams. The pistons cause columns of fluid to alternate between motor and generator, producing synchronous rotation. Apparatus for synchronizing, coupling and decoupling the motive force are disclosed.