A hydrostatic axial piston machine includes a pressing pressure chamber for the cylinder drum which is supplied with pressing pressure from a circular-arc-like elongate hole of a distributor plate or from a plurality of connection channels of the cylinder drum. The pressing pressure chamber is delimited radially outwardly by the cylinder drum and radially inwardly by the drive shaft. The pressing pressure chamber is delimited axially at both sides by seals which are both arranged between the radially inner rotating drive shaft and a radially outer stationary component. The radially outer component may be the cylinder drum or, in the case of the distributor-plate-side seal, also a gap seal between the drive shaft and a bearing bush of the distributor plate. Both seals are arranged at the distributor plate side with respect to a tooth arrangement or a retraction ball.

A rotary piston engine comprising, a cylindrical rotatable rotor with an output shaft and a plurality of longitudinally extending cylinder-forming bores, each having a slidable piston disposed therein, where the rotor is contained in a housing whose interior contains a cam track that interacts with the pistons to move them back and forth within their respective cylinders in response to rotation of the rotor. A rear end cap on the housing contains an arcuate opening for admitting ambient air into the cylinders on the rear side of the pistons and an arcuate port for delivery the air driven by the rear side of the pistons into a transfer manifold that directs the air to an intake port in the side of the housing where, in response to the angular position of the rotor, the air is admitted to the front side of a piston for compression with injected fuel. A spark plug ignites the compressed fuel-air mixture and an exhaust port in the side of the housing opens to discharge the products of combustion in response to the angular position of the rotor.

A hydrostatic axial piston machine includes a pressing pressure chamber for the cylinder drum which is supplied with pressing pressure from a circular-arc-like elongate hole of a distributor plate or from a plurality of connection channels of the cylinder drum. The pressing pressure chamber is delimited radially outwardly by the cylinder drum and radially inwardly by the drive shaft. The pressing pressure chamber is delimited axially at both sides by seals which are both arranged between the radially inner rotating drive shaft and a radially outer stationary component. The radially outer component may be the cylinder drum or, in the case of the distributor-plate-side seal, also a gap seal between the drive shaft and a bearing bush of the distributor plate. Both seals are arranged at the distributor plate side with respect to a tooth arrangement or a retraction ball.

A hydraulic axial piston machine (1) is described, the machine comprising a housing, a cylinder block (2) rotatably mounted in the housing about an axis or rotation (7) and having at least one cylinder (3), and a valve arrangement (4) between the cylinder block (2) and the housing, the valve arrangement having a first part (4) rotating with the cylinder block (2) and a second part mounted stationary with respect to the housing. Such a machine should have a high efficiency. To this end the first part (4) comprises an elastically deformable spring section (9).

The present invention relates to a pump (1) comprising two pumping assemblies distributed symmetrically about a plane perpendicular to the axis of a driveshaft (12), each pumping assembly comprising a cylinder (4, 5), a plate (2, 3), an intake pipe (8, 9) and a delivery pipe (10, 11), the plates (2, 3) of each assembly being connected to one another at said plane of symmetry.

Hydraulic axial piston unit (1) of the swashplate construction type having a drive shaft (2) adapted to drive or be driven by a cylinder block (4). The cylinder block comprises a plurality of cylinder bores (6), in which several pistons (8) are moveable in general along the rotational axis (10) of the drive shaft (2) and relative to the cylinder bores (6). First ends of the pistons (8) protrude outside of the cylinder bores (6) and are slidable fixed by means of slippers (14) to a swashplate (16). The slippers (14) are hold down in a sliding manner on a sliding surface (18) of the swashplate (16) by means of a slipper hold down ring (20) arranged parallel to the sliding surface (18). The slipper hold down ring (20) is in a sliding contact with its radial inner surface (22) with a matching surface (26) on a guide ball (24) rotationally fixed on the drive shaft (2) and axially moveable in direction of the rotational axis (10) relative to the cylinder block (4) against resilient forces of springs (28) characterized in that a mounting ring (30) is attached to the cylinder block (4) in order to limit the axial movement of the guide ball (24) towards the cylinder block (4).

A rotary piston engine having a rotor with an output shaft and a plurality of longitudinally extending cylinder-forming bores, each having a slidable piston disposed therein. The rotor is contained in a housing that contains an elliptical cam track that interacts with the pistons, upon combustion, to cause rotation of the rotor. An opening in the housing end cap admits air into the cylinders on the rear side of the pistons and a port delivers air driven by the rear side of the pistons to an intake port in the side of the housing where, in response to the angular position of the rotor, the air is admitted to the front side of a piston for compression with injected fuel. The compressed fuel-air mixture is ignited and an exhaust port in the side of the housing opens to discharge the products of combustion.

Hydraulic axial piston unit (1) of the swashplate construction type having a drive shaft (2) adapted to drive or be driven by a cylinder block (4). The cylinder block comprises a plurality of cylinder bores (6), in which several pistons (8) are moveable in general along the rotational axis (10) of the drive shaft (2) and relative to the cylinder bores (6). First ends of the pistons (8) protrude outside of the cylinder bores (6) and are slidable fixed by means of slippers (14) to a swashplate (16). The slippers (14) are hold down in a sliding manner on a sliding surface (18) of the swashplate (16) by means of a slipper hold down ring (20) arranged parallel to the sliding surface (18). The slipper hold down ring (20) is in a sliding contact with its radial inner surface (22) with a matching surface (26) on a guide ball (24) rotationally fixed on the drive shaft (2) and axially moveable in direction of the rotational axis (10) relative to the cylinder block (4) against resilient forces of springs (28) characterized in that a mounting ring (30) is attached to the cylinder block (4) in order to limit the axial movement of the guide ball (24) towards the cylinder block (4).

A hydrostatic axial piston machine is disclosed, in the housing of which a drive shaft is rotatably mounted about an axis of rotation. The housing comprises a pot-like housing part having a first abutment and a cover-like housing part having a second abutment. The two abutments are clamped against one another in a sealing manner. A first fitting pin is inserted precisely into a first fitting recess of the first abutment on the one hand and into a second fitting recess of the second abutment on the other hand. A second fitting pin is provided on a side opposite the axis of rotation, which is inserted precisely into a third fitting recess of the first abutment on the one hand and into a fourth fitting recess of the second abutment on the other hand. The second fitting recess has a radial widening relative to the axis of rotation, whereby the second fitting recess is a slotted hole and/or a fitting groove.