Abstract: A radial piston pump includes a pair of inboard trunions which provide tilting bearing support for the swashplate. The trunion blocks may be made from sections of ordinary cold rolled steel bar stock and attached to the end wall of the pump housing with externally accessible bolted connections which allow final precise alignment of the trunion blocks in the assembled pump. The swashplate includes a concave cylindrical bearing surface which rides on the trunion blocks and, to enable precision finishing and machining of the concave bearing surface in a simple manner. Two swashplates are made from a single metal casting in which a full cylindrical through bore can be accurately cut and finished, and the casting subsequently cut in two to provide two swashplates. The swashplate is mounted with its transverse tilt axis offset from the axis of the pump drive shaft in a direction providing a net imbalance in piston spring biasing force to urge the swashplate on-stroke to enhance start-up operation.

Abstract: A plunger and swash-plate type hydraulic pump or motor with a retainer plate 30 that presses a slidable abutment 22 of each of a plurality of shoe members 20 against a slidably abutting surface 8a of a swash-plate 8 in such a manner that a neck 21 of each shoe member is inserted into each of a plurality of insertion holes 31 of the retainer plate 30. An imaginary center plane C.sub.3 or C.sub.4 of the part of the inner surface of each of the insertion holes 31 which abuts against the outer periphery 21a of the neck 21 is coincident with the center O.sub.2 around which each of the shoe members 20 swings relatively to the plunger 10 in the axial direction of each of the insertion holes 31.

Abstract: A new kind of rotary piston machine with sealed work chambers and a wear resistant driving mechanism. Pivotal pistons move within respective cylinders and both the pistons and the cylinders revolve about circular orbits which are relative to one another. Both pistons and cylinders are included in a single piece rotor of unitary construction and can have either an axial or a radial configuration. Single-cylinder or multi-cylinder engines are included. This invention eliminates the necessity of piston bearings and thus, provides a wear-resistant, oil-free, driving mechanism. This invention further unites the sealing performance of the classical piston machine with the kinematic qualities of the rotary system.

Abstract: An integrated drive generator for an aircraft and a method of making and operating the same result in improved operation of the integrated drive generator, especially during cold start-up. This is accomplished through the use of at least one stop to prevent each of the cylinder blocks in the hydraulic pump and motor assembly of the integrated drive generator from moving away from the port plate more than a predetermined amount which will ensure establishment of hydraulic continuity between the pump and motor without substantial delay during cold start-up of the integrated drive generator.

Abstract: An axial piston pump apparatus includes a rotary cylinder barrel with plural cylinder bores in each of which a slidable piston is arranged. Each piston is rotatably held at one end with a piston support synchronously rotatable with the cylinder barrel. The piston support rotates in a plane inclined to the cylinder barrel, while each piston reciprocally moves in the corresponding cylinder bore to perform suction/discharging of a fluid. Two of the pistons come into surface contact with the corresponding cylinder bores; and the end of these pistons are held respectively in the piston support for radial movement to serve as drive pins for transmitting torque between the cylinder barrel and the piston support. During operation of the pump apparatus, the one end of each drive piston radially moves in accordance with rotation of the piston support, thereby preventing the drive pistons from inclining to the corresponding cylinder bores and appropriately maintaining surface contact between them.

Abstract: A fixed swash plate for an axial piston machine of fixed capacitive type, which has a casing housing therein a cylinder, is formed to have its divided surfaces on the horizontal plane along the axis of the rotary shaft of the cylinder, wherein a support member constituting a fixed swash plate is formed to be easy to produce and the casings merely sandwich therebetween the support member, whereby a thrust bearing constituting the fixed swash plate is held in the state of being slanted at a predetermined angle other than 90.degree. with respect to the axis of rotary shaft. Also, the rotation direction of the fixed capacitive type axial piston machine is easy to change by inverting at an angle of 180.degree. the assembling direction of support member constituting the fixed swash plate.

Abstract: An axial piston machine has a housing with a cover, a swash plate located within the housing and an elongated rotary shaft extending through the swash plate and the housing with an end in the housing cover. A cylindrical drum is connected to the shaft for rotation therewith and one end of the cylindrical drum abuts against a surface of a control member located in the housing adjacent to the housing cover. A number of concentrically arranged cylindrical passages are formed in the cylindrical drum and a longitudinally moveable hollow piston is located in each cylindrical passage. A slide shoe is located at one end of each piston and each slide shoe is in working connection with the swash plate. Each slide shoe has a slide shoe plate, a slide shoe neck and a slide shoe head connected to one of the pistons. The face of each slide shoe plate which is opposed to the swash plate is in contact with an annular, spring-loaded retaining plate which is provided with a number of concentrically arranged recesses.

Abstract: A swashplate type hydraulic axial piston machine whose swashplate is arranged on a rocker mounted to pivot in a segmental rolling contact bearing has a tracking device for the cage of the pivot bearing which comprises a rod-like guide element which is connected to said rocker in a first bearing in the rocker so that it can pivot parallel to the pivot plane (SE), is connected to said cage in a second bearing so that it can pivot parallel to the pivot plane (SE) and so that it can be displaced longitudinally, and is mounted to pivot parallel to the pivot plane (SE) in a third bearing. To make tracking by the cage possible without mounting the guide element on the housing, a rocker adjustment member is provided mounted so that it can be displaced transverse to the middle axis of the axial piston machine, and the third bearing is arranged on a guide member movably connected to the adjustment member and the rocker.

Abstract: A swash-plate type piston pump motor has a housing assembly comprising: an end plate for rotatably supporting a cylinder rotor against thrust loads in its axial direction and also rotatably supporting the upper end of an output shaft; a cylinder side peripheral wall encompassing the cylinder rotor; an inner peripheral wall which is joined contiguously to the cylinder side peripheral wall and extends downward toward the lower end of the output shaft. The inner peripheral wall encloses and supports a swash plate in an inclined state. A downwardly extending outer peripheral wall is also joined contiguously to the cylinder side peripheral wall and is flared outward toward the lower end of the output shaft, an annular space being formed between the inner and outer peripheral walls. The maximum flare angle of the outer peripheral wall relative to the axial direction of the output shaft is 30 degrees. The outer peripheral wall has at its open flare extremity a motor mounting flange.

Abstract: A piston drive such as a piston drive for actuating a valve includes a piston which reciprocates between two end positions which are defined by respective sleeve-shaped inserts projecting into the path of movement of the piston and being axially displaceable by respective worm drives. One insert with the pertaining worm drive is usable for emergency actuation while the other insert with the pertaining worm drive is usable for limiting the stroke of the piston.

Abstract: A bent-axis hydraulic apparatus having a case in which a rotatable cylinder block is positioned and which is associated with a rotatable shaft at a drive angle therebetween. A split angle spline drive interconnects the cylinder block of the hydraulic axial piston unit with a rotatable shaft for transmission of torque therebetween without any side loading on the pistons of the axial piston unit. The split angle spline drive has two series of external teeth associated one with the cylinder block and the other with the rotatable shaft which individually mesh at two locations opposite the axis of rotation thereof with two spaced-apart sets of internal teeth on a ring gear that is rotatably-mounted in fixed location within the case of the hydraulic apparatus. The tooth mesh center lines are equally spaced from the pivot point for the cylinder block and the rotatable shaft to achieve synchronization.

Abstract: A swashplate type variable displacement hydraulic device is so constructed that a plurality of plungers are slidably received in a plurality of cylinder bores arranged annularly around an axis of rotation, a back surface of a swashplate of which a fore surface is engaged by outer ends of the plungers is supported by a swashplate holder via bearing means, and a stationary swashplate anchor supports the swashplate holder to turn about a trunnion axis which intersects the axis of rotation at right angles. Opposing surfaces of the swashplate holder and swashplate anchor are formed as spherical surfaces of which a center is located at a position where the axis of rotation intersects the trunnion axis, the swashplate holder has a pair of trunnion shafts projected from opposite ends of the swashplate holder while extending along the trunnion axis, and the trunnion anchor is formed at opposite ends thereof with recesses with which the trunnion shafts are rotatably engaged.

Abstract: An adjustable axial piston machine is disclosed which has a housing, a cylinder drum and an operating cylinder-servo piston unit capable of being acted upon by control pressure. The cylinder-servo piston unit has a movable part which is being connected with a control of the axial piston machine. The operating cylinder-servo piston unit has an annular configuration and is located around the cylindrical drum.

Abstract: A cylinder block for a multi-cylinder hydraulic or hydrostatic piston device is provided having a control layer comprising a sintered friction metal layer sintered onto the cylinder block under the simultaneous action of pressure and heat. The end surface of the cylinder block is first provided with an electrodeposited metal layer. The electrodeposited layer has a crystal lattice constant compatible with the sintered layer and the material of the cylinder block. The cylinder block is preferably made from steel or aluminum and the electrodeposited layer is preferably copper or nickel. After the friction metal layer, preferably bronze, is sintered onto the electrodeposited layer, the cylinder block is treated to improve the strength and wear characteristics of the cylinder block without injuring the sliding friction characteristics of the sintered friction metal layer.

Abstract: In an axial piston motor or pump the cylinder barrel is mounted on a medial shaft which has a shoulder which axially bears against the front end of the rotor barrel. The rear end of the medial shaft is radially borne in a housing portion. The front portion of the medial shaft is provided with a bearing member of an axial thrust bearing for support on a respective axial thrust bearing member in the housing. On the rear end of the rotary barrel an axially selfthrusting control body is provided to seal the flow of fluid to and from the cylinders of the rotary barrel. The control body presses against the rotary barrel, the rotary barrel presses against the bearing of the medial shaft and the thrust bearing member of the shaft bears on the thrust bearing member of the housing. As a result thereof the cylinders in the rotary barrel can be straight through bores. The manufacturing of the rotor barrel is thereby simplified and the flow acceleration losses of former sack-bare bore type cylinders are prevented.

Abstract: A thrust hydrostatic bearing device for use in an axial piston machine includes a bearing sleeve fitted into a housing cover for rotatably supporting a drive shaft through a bearing and having a plurality of hydrostatic pads. The hydrostatic pads are disposed at locations which are symmetrical with respect to an axis lying in a cross-section taken perpendicular to the drive shaft, and these pads increase the performance and durability of the thrust hydrostatic bearing device for use in an axial piston machine.

Abstract: The invention relates to an adjustable axial piston engine having spaced apart end walls with a shaft extending between the end walls. A rotary carrier is attached to the shaft adjacent one of the end walls and an oblique adjusting plate is mounted adjacent the other end wall. A piston-cylinder unit extends between the carrier and the oblique plate. A pivot axis for the oblique plate includes a bearing arrangement between the plate and the adjacent end wall. A servo unit for adjustably rotating the plate about the pivot axis is provided between the plate and the adjacent end wall. The piston-cylinder unit is carried by the carrier and is slidably engageable with the oblique plate. Flanges are provided for the piston-cylinder units which are spring biased into engagement with the oblique plate via a spring biased pressure plate.

Abstract: A hydraulic transmission device operable to translate hydraulic energy into mechanical energy and vice versa. The device has a housing 14 having a close end portion and an open end portion in the longitudinal direction. The housing supports therein a drive shaft 11, a retainer 12, and a cylinder block 13 which have an integral structure. A recess is formed at a substantially central location of the end surface of the cylinder block 13 that is on the side of an open end of the housing, and a cover 15 closing the open end of the housing has a protruding portion 15A which extends through a port plate 23 to be engaged with the recess of the cylinder block through a bearing 17. A plurality of pistons are disposed in the cylinder block and are kept in tight engagement with a swash plate fixed to the closed end portion of the housing at a constant tilt angle. The device acts as either a swash plate type axial piston pump or motor of this type as the drive shaft rotates.

Abstract: The invention relates to an axial piston machine having an oblique disk body (14) arranged in a housing (1) in a torsionally secure manner, having a drive shaft (4), which is mounted in the oblique disk body (14), and having a rotatable cylinder drum (7), which is coupled with the drive shaft (4) and in which a plurality of pistons (9) may be displaced axially in piston bore holes, their piston heads (11) being supported by means of sliding shoes (12) against the oblique surface (13) of the oblique disk body (14). The purpose of the invention is to construct the axial piston machine in such a way as to make possible torsional securement of the oblique disk body (14) which is simple in terms of production techniques and assembly, with a compact constructional form. This is achieved by mounting the oblique disk body (14) with its peripheral surface (16, 17) torsionally secured in a form-locking manner in a recess (19) of the housing (1) shaped to correspond to the peripheral surface (16, 17).

Abstract: A swash plate (3) incorporated in a swash plate type compressor and comprising a boss (10) typically formed of aluminum material, which is fixedly secured on a drive shaft (2), and a swash plate assembly (11) extending obliquely from the boss (10), which assembly comprises a pair of front and rear contact plates (12) made of iron and brought into contact with a pair of shoes (6) which are accommodated in recesses (15a) of a piston (5), a connecting member (13) made of iron rigidly connecting the pair of contact plates (12), and a filler (14) made of aluminum material which completely fills the internal spaced formed between the contact plates (12).

Abstract: An axial piston pump is disclosed which includes a housing, a cylindrical bore in the housing, a piston barrel rotatable in the bore and spaced from the bore walls and an antifriction bearing structure surrounding the barrel between the barrel and the bore. A plurality of axial piston are provided in the barrel which are open at one end and have fluid passages through the barrel at the other end. A piston is provided in each such piston bore which extends out of the open end. A spring is provided between each piston and the other end of the piston bore. A fixed ramp swash plate is provided in the housing bore beneath the extending pistons and an antifriction thrust bearing is provided between the swash plate and pistons. An axial drive shaft is provided on the barrel which extends through an antifriction bearing in an opening in the housing opposite the bore for drivingly engaging on external drive structure.

Abstract: A swashplate type hydraulic pressure device comprising a cylinder and a swashplate which is rotatable relative to the cylinder and rotatably supported on a holder, the cylinder having a number of plungers disposed thereon axially slidably in an annular arrangement, in which a spherical end is formed at that extreme end of each plunger which is in abutment with the swashplate, and the swashplate is provided with a spherical concave portion for engagement with the spherical end. By cooperation between the spherical concave portions and the ends, the cylinder rotates synchronously with the swashplate and an aligning action is imparted to the swashplate from the group of plungers of the cylinder.

Abstract: A swash plate plunger type pump-motor comprises a casing, a rotatable cylinder block formed with chambers, a plurality of plungers axially slideably received in the chambers, rotatable swash plate rotatably supported through a bearing within the casing, a plunger retainer adapted to prevent the plungers from disengaging from the swash plate, and a rotational shaft on which the cylinder block is fixedly mounted. The plunger retainer and the swash plate are connected with each other in such a manner that the front faces of the plunger head portions contact the swash plate and that the rear faces of the plunger head portions contact the plunger retainer. The rotational axis of the swash plate is inclined at a predetermined angle with respect to the rotational axis of the rotational shaft.

Abstract: In an axial piston motor or pump the cylinder barrel is mounted on a medial shaft which has a shoulder which axially, bears against the front end of the rotor barrel. The rear end of the medial shaft is radially borne in a housing portion. The front portion of the medial shaft is provided with a bearing member of an axial thrust bearing for support on a respective axial thrust bearing member in the housing. On the rear end of the rotary barrel an axially selfthrusting control body is provided to seal the flow of fluid to and from the cylinders of the rotary barrel. The control body presses against the rotary barrel, the rotary barrel presses against the shoulder of the medial shaft and the thrust bearing member of the shaft bears on the thrust bearing member of the housing. As a result thereof the cylinders in the rotary barrel can be straight through bores. The manufacturing of the rotor barrel is thereby simplified and the flow acceleration losses of former bag bore type cylinders are prevented.

Abstract: A hydraulic displacement unit of the axial piston fixed displacement type having a rotatable cylinder block with axially reciprocal pistons, each of which has a slipper associated with a swash surface, as defined by a thrust plate, and structure for obtaining fixed maximum clearance between the slippers and the thrust plate. This fixed maximum clearance is achieved by the use of the controlled positioning of a slipper retainer bearing relative to the surface of the thrust plate by use of a tubular member positioned within the cavity of the unit housing which is securely located and positioned by assembly of an end cap to the housing to be located between the thrust plate and the end cap.

Abstract: The invention relates to a hydrostatic axial piston machine (1) having a cylinder drum (9), rotating in a housing, which cylinder drum receives pistons (12) arranged on a pitch circle, and having an inclined disc (16) which pivots, in a pivot, about a swivelling axis (21) which extends eccentrically to the pitch circle, which pivot is formed by at least one bearing (23) having a bearing surface (26) which is free in the direction of the pistons (12), the inclined disc (16) being arranged loosely between the bearing (23) and the pistons (12) and being pivotable by means of an adjusting member (28). The aim of the invention is to develop the axial piston machine so that, while ensuring a simple structural design sign and simple assembly and dismantling of the inclined disc (16) and of the adjusting member (28), defined limitation of the adjusting movement of the inclined disc (16) in the direction of zero position or minimum delivery is possible.

Abstract: An axial piston motor is provided having a mechanical friction brake incorporated in the driving flange, thereby maintaining the axial length of the motor the same as motors without a mechanical friction brake.

Abstract: A hydrostatic piston machine has a housing, a rotor, a plurality of pistons rotatable with the rotor, and a displacing element operative for effecting reciprocation of the pistons and having a surface which is in sliding contact with the latter. Means is provided for reducing friction between the surface of the displacing element and the pistons during the sliding contact. This means includes a recess formed in the surface of the displacing element and communicating with a space which is under pressure so that a cushion of pressure fluid develops between the surface and the piston. The space under pressure may be constituted by a low pressure zone of the machine or by the low pressure and a high pressure zone of the machine.

Abstract: A piston and cylinder machine, e.g. an engine or pump, in which the cylinder rotates about a first axis from which the cylinder is spaced, and the piston rotates about a second axis inclined to the first with the result that during the rotation, the piston reciprocates relative to the cylinder. Gas flow is controlled by a rotary valve which communicates with the cylinder and which rotates about an axis parallel to or coincident with the first axis. The piston is maintained in position relative to the cylinder by restraining means in the form, for example, of flat abutment surfaces provided between the piston and a spherically-surfaced piston ring thereon so as to limit lateral movement of the piston ring relative to the piston.

Abstract: A piston and cylinder machine of the kind in which there is a wobble mechanism for reciprocating the piston in the cylinder or an arrangement in which a piston assembly and a cylinder assembly rotate about respective inclined axes so that such rotation is accompanied by relative reciprocation of the piston and cylinder, is provided with a piston having a part which has a surface exposed inside the cylinder to define at least a part of one end of a chamber therein and which, to provide sealing of the chamber, has a peripheral surface forming a sphere. Improved torque transmitting or reacting means for maintaining the correct relative orientation of the piston and cylinder are provided.

Abstract: An axial-piston hydraulic machine with a rotating cylinder block. The axial bores of said cylinder block accommodate reciprocating pistons. Said pistons restrict the working chambers some of which communicate through a passage with a high-pressure zone while the others communicate through a passage with a low-pressure zone. The surface of each working chamber at its minimum volume is spherical and merges smoothly with the passage.

Abstract: A swash plate pump or motor is provided having a swivel plate surrounding the slippers and a positive hold down ring connected to the swash plate and bearing on said swivel plate to maintain it at a fixed distance from the slipper plate, said hold down ring having a series of successive controlled wedge angles on the face bearing on the swivel plate and oil feed means connected to each wedge angle whereby a hydrodynamic force is created holding the swivel plate and hold down ring apart.

Abstract: An axial piston machine comprising a casing which encloses and mounts the machine working parts therein and a cover of pliant material mounted externally of the casing to substantially entrap a quantity of air or other gas against at least a part of the outer surface of the casing to reduce noise radiation from the casing.

Abstract: In a hydraulic axial piston machine, which may be a pump or hydraulic motor, whose cylinders are located on a larger circle than the cylinder ports and the stationary high pressure and low pressure ports of a stationary body, a tilting moment is exerted on the cylinder block which is compensated by radial pressure exerted on the cylinder block by positioning cylinder and piston members operated either directly by high pressure fluid from the high pressure conduit of the stationary body, or indirectly under the control of a valve operated by leakage fluid obtained from a recess in the control face of the stationary body.

Abstract: An axial bearing device is provided for the cylinder barrel in an axial piston machine, particularly of so-called bent-axis type, i.e. with the axis of the barrel inclined to the axis of the drive disk. The barrel is rotatably journalled in a housing, which is open at one end, and adapted to be resiliently urged by means of a spring member against a valve disk at the other end of said housing, which is closed. The spring member comprises an elongated leaf spring which at one end is fixed at a position on the inside of the housing and at the other engages a bearing ring located in a raceway radially outwardly of the mouths of the cylinder bores at the end of the cylinder barrel remote from said valve disk.

Abstract: A skid-steered vehicle, especially an end loader, having a hydrostatic transmission. The transmission will have a series pump unit comprising two pump sections separated by a midplane porting block. Each pump section includes an axial piston group rotating on a common axis on opposite sides of the block. A pair of arcuate ports in each side of the block circumjacent the axis of rotation are in fluid communication with each piston group. Internal passages within the block include at least one passage communicating with one arcuate port of each pair which crosses from one side of the axis of rotation to the other before reaching an exposed surface of the block. In this manner, the external crossing of hydraulic hoses is eliminated facilitating shorter, more direct hydraulic coupling with associated hydraulic components.

Abstract: A swashplate type hydraulic pressure device comprising a cylinder and a swashplate which is rotatable relative to the cylinder and rotatably supported on a holder, the cylinder having a number of plungers disposed thereon axially slidably in an annular arrangement, in which a spherical end is formed at that extreme end of each plunger which is in abutment with the swashplate, and the swashplate is provided with a spherical concave portion for engagement with the spherical end. By cooperation between the spherical concave portions and the ends, the cylinder rotates synchronously with the swashplate and an aligning action is imparted to the swashplate from the group of plungers of the cylinder.