A hydrostatic axial piston machine includes a housing and a pivot cradle. At least one slide bearing of the pivot cradle on a high-pressure side is hydrostatically relieved. The slide bearing includes one or two pairs of relief grooves. A relief pressure field develops about and between the one or two pairs of relief grooves as the grooves are supplied with relief pressure medium on one side and are closed at their outer ends. An optional slide bearing on a low-pressure side has one or two limiting grooves which delimit the relief pressure field there, as the limiting grooves are open at their outer ends.

A hydraulic rotary machine configured to reduce sliding resistance of a reciprocating piston and to suppress a reduction in volumetric efficiency corresponding to an amount of leakage of hydraulic oil. A piston pump includes a rotor shaft, a cylinder block, a piston head, a piston rod, a retainer, a swash plate, and a tilt regulation mechanism. When the tilt regulation mechanism rocks the swash plate, the amount of discharge from the piston pump is variably changed. The retainer which rotates with both the piston head and the piston rod is supported by a retainer bush provided to the rotor shaft. The retainer sphere section of the retainer and the retainer bush sphere section of the retainer bush have spherical shapes having the same curvature. During the regulation of tilt, the retainer rocks while the retainer bush sphere section is in sliding contact with the retainer bush.

An adjusting device for an axial piston machine includes an actuating piston that delimits an actuating space configured to be connected to a control oil source or a control oil drain via a control valve. A control piston of the control valve is loaded firstly by a control spring and secondly by a spring arrangement that is also in active engagement with the actuating piston.

Displacement control device (1) for variably adjusting the displacement of an axial piston hydraulic pump comprising a rotary shaft (10) mounted in a housing (20) and rotatable around a shaft axis (13) of the rotary shaft (10). The rotary shaft (10) having a first end (11) and a second end (12), wherein to the second end (12), which protrudes outside of the housing (20), a torque can be applied for rotating the rotary shaft (10) to open and close servo pressure lines (40, 45) arranged within the housing (20). The servo pressure lines (40, 45) can conduct hydraulic fluid to and from a servo adjusting unit capable to adjust the displacement volume of the axial piston hydraulic pump. The rotary shaft (10) further comprising a mid-portion (14) located between the first end (11) and second end (12). Concentric to the shaft axis (13) in the mid-portion (14) of the rotary shaft (10) a detent sleeve (5) is positioned comprising an abutment area (7) onto which, in the neutral position of the displacement control device (1), a sliding element (8) abuts, which is mounted pre-stressed in the housing exerting a resilient force onto the detent sleeve (5) perpendicular to the shaft axis (13), wherein the detent sleeve (5), in operating conditions of the displacement control device (1) is rotatable fixed with the rotary shaft (10) and turns with the rotary shaft (10). However, for neutral position adjustments in non-operating conditions, the detent sleeve (5) and the rotary shaft (10) are detachable from each other such that the rotary shaft (10) can be turned relative and independently within the detent sleeve (5), which is held in its neutral position by the sliding element (8).

The device has an internal distributor to be disposed in a casing portion (10A), and has a body (15) that has an outside axial face (15B) provided with two grooves (17, 19) respectively for feed and for discharge. The distributor has distribution ducts (23A, 23B, 23C) that open out in a distribution radial face and a cylinder capacity selector that has a slide (50) suitable for being moved in an axial bore (53) for connecting the distribution ducts to one or the other of the grooves. The device further has a control chamber (52) provided between a first end wall (15) of the bore and the first end (50A) of the slide, and an opposing spring (55) disposed in a return chamber (52) situated at the second end (53) of the bore and closed, at the end closer to the distribution face (15A), by a second end wall (55) of the distributor.

Hydrostatic radial piston unit comprising a front case part accommodating a drive shaft via shaft bearing means so that the drive shaft can rotate around a central axis relative to the front case part. A rear case part is attached on one side to the front case part and closed on another side in order to define an internal volume. A cylinder block is disposed in the internal volume and attached to the drive shaft in a torque proof manner. Axially disposed timing holes in the cylinder block connect radially oriented working volumes in the cylinder block with a cylinder block front face that is arranged perpendicularly to the central axis and faces away from the front case part. Integrally within the rear case part internal annular flow passages are formed and are connected to an inlet and an outlet of the radial piston unit and running basically in circumferential direction around the central axis. Internal distribution conducts configured to hydraulically connect the internal annular flow passages with the cylinder block timing holes are integrally formed within the rear case part, too.

The present disclosure relates to an adjusting device for adjusting the swash plate of an axial piston machine comprising an adjusting piston, which is connected to the swash plate of the axial piston machine via an adjusting lever, and a regulator for adjusting the adjusting pressure acting on the adjusting piston in dependence on a control force acting on a control piston of the regulator, wherein the adjusting piston is connected to the control piston via a feedback spring.

A low-energy and high pressure, hydraulic, pneumatic engine contains: a casing device, two main-cylinder devices, a holder device, two main-crankshaft devices, two recycle-valve devices, two swing-arm devices, two movable-valve devices, two recycle-cylinder devices, two recycle-crankshaft devices, and two umbrella-shaped gear devices. The engine operates without using gasoline or diesel, thus avoiding discharge of harmful substance or gas and pollution. The high pressure gas forces the hydraulic oil without using gasoline or diesel so as to start the engine, and the hydraulic oil recycles and reuses repeatedly, thus obtaining environmental protection. And the high pressure gas forces the hydraulic oil so as to circulate the hydraulic oil, and the communication of the low-energy and high pressure and the low pressure matches with the circulation space of the fluid operation to produce the torque, hence four strokes cycle of intake, compression, combustion and exhaust are not required.

A hydrostatic axial piston pump of swashplate construction, which is also configured to be operated as a motor, has a stationary control plate against which a rotating cylinder drum is tensioned. During operation, a tilting tendency of the cylinder drum arises in the direction of that quadrant of the control plate which is operatively connected to the first part of the displacement stroke of the pistons. The control plate has a supporting device configured for the cylinder drum. The supporting device is arranged adjacent to an outer edge of the control plate in the first quadrant thereof. The supporting device is configured to be formed by a hydrostatically relieved additional field.

A swashplate-type axial piston machine includes a housing, a first pivot bearing received in the housing, a drive shaft rotatably mounted in respect of an axis of rotation, a cylinder drum, a control plate, a third control aperture in the plate, and a first channel arranged in the housing. The first pivot bearing delimits a first and second housing space from one another. The drum and the plate are arranged in the first housing space. The plate has at least a first and at least a second control aperture. The first aperture is in fluidic exchange connection with a first fluid connection on the housing. The second aperture is in fluidic exchange connection with a second fluid connection on the housing. The third aperture is arranged in the peripheral direction between a first and a second aperture. The first channel fluidically connects the third aperture to the second housing space.