A hydraulic device (1) comprises a housing (27), a shaft (2) which is mounted in the housing (27) and rotatable about a first axis of rotation (4), wherein the shaft (2) has a flange (8) extending perpendicularly to the first axis (4), a plurality of pistons (9) which are fixed to the flange (8) at equiangular distance about the first axis of rotation (4), and a plurality of cylindrical sleeves (10) cooperating with the pistons (9) to form respective compression chambers (11) of variable volume. The sleeves (10) are rotatable about a second axis of rotation which intersects the first axis of rotation (4) by an acute angle such that upon rotating the shaft (2) the volumes of the compression chambers (11) change. Each piston (9) has a piston head (14) including a ball-shaped circumferential outer side. Each of the pistons (9) has a modular structure comprising a piston head member (14) which forms the piston head, a piston pin (20) which is fixed to the flange (8) and to which the piston head member (14) is mounted, and a spacer (26) which is located at the outer side of the piston pin (20) and sandwiched between the piston head member (14) and the flange (8).

The present invention relates to a method of manufacturing a drum of an axial piston machine by machining a cylindrical round metal, with the machining comprising a forging and with at least one structural element of the drum being produced or prefabricated by the forging.

The present invention relates to a method of manufacturing a drum of an axial piston machine by machining a cylindrical round metal, with the machining comprising a forging and with at least one structural element of the drum being produced or prefabricated by the forging.

A hydrostatic piston machine unit, which is in particular designed as a hydrostatic axial piston machine unit, comprises at least two driving mechanisms that can be driven synchronously and have displacement pistons which each perform a reciprocating motion in operation and are provided for delivery into a common pressure line. The hydrostatic piston machine unit has a jointly assigned precompression volume for the at least two driving mechanisms.

A hydrostatic piston machine unit, which is in particular designed as a hydrostatic axial piston machine unit, comprises at least two driving mechanisms that can be driven synchronously and have displacement pistons which each perform a reciprocating motion in operation and are provided for delivery into a common pressure line. The hydrostatic piston machine unit has a jointly assigned precompression volume for the at least two driving mechanisms.

A fluid pump is proposed. The fluid pump includes: a housing having an operation space and having connection ports disposed at a side in the operation space to discharge working fluid and suctioning working fluid from the outside; a swash plate coupled to the housing at an opposite side to the connection ports and having an inclined surface on a top facing the operation space; a cylinder block disposed in the operation space to be rotated by a driving shaft and having several cylinder rooms therein that extend in parallel with the driving shaft.

A hydraulic machine includes a housing interior space and a group of hydrostatic working chambers which are mounted in said housing interior space so as to be rotatable about an axis of rotation and which, as the group rotates, are connectable alternately to a high pressure and to a low pressure of the hydraulic machine and exhibit leakage into the housing interior space. A heat exchanger device is accommodated in the housing interior space. The hydraulic machine may be associated with a hydraulic assembly and a hydraulic axle.

A piston pump includes a first biasing mechanism configured to bias a swash plate in accordance with supplied control pressure, a second biasing mechanism configured to bias the swash plate against the first biasing mechanism, and a regulator configured to control the control pressure led to the first biasing mechanism in accordance with discharge pressure of the piston pump, wherein the second biasing mechanism has a pressure chamber to which the discharge pressure is led, and a control piston configured to be biased toward the swash plate by the discharge pressure led to the pressure chamber, and the regulator has a biasing member configured to bias the control piston toward the swash plate, and a control spool configured to be moved in accordance with biasing force of the biasing member, the control spool being configured to adjust fluid pressure.

A hydrostatic axial piston machine has a drive shaft penetrating a housing on either side. In this case, the mechanically weaker of the two shaft ends is strengthened by an undercut being eliminated, said undercut defining the minimum diameter of the shaft end and thus of the entire drive shaft. Instead, the strength of the relevant shaft end is increased by a displacement of a circular bearing surface for a rolling bearing radially outwardly and away from the rolling bearing. In this case, the circular bearing surface is displaced below a compression spring which clamps the cylinder drum against a distributor plate. The resulting spacing between the circular bearing surface and the rolling bearing remaining in place is bridged by a sleeve or by a ring. A concave rounded shaft shoulder is simply formed below the sleeve and/or the ring.

A hydraulic device (1) comprises a housing (2) and a shaft (3) which is rotatable about a first axis of rotation (4). The shaft (3) has a flange (8), a partly spherical portion (16) and a plurality of pistons (9), which are fixed to the flange (8). The device (1) also has a plurality of cylindrical sleeves (11), wherein each sleeve (11) has a sleeve bottom (13) comprising a sleeve opening (14) including a centreline (23). The sleeves (11) cooperate with the pistons (9) to form respective compression chambers (12) of variable volume. A barrel plate (15) is mounted on the partly spherical portion (16) and has barrel plate ports (21) including respective centrelines (22). The sleeves (11) are rotatable about a second axis of rotation (19) which intersects the first axis of rotation (4) by an acute swash angle. The barrel plate (15) is coupled to the shaft (3) in rotational direction thereof by means of a plurality of pin-groove couplings creating a plurality of pivot axes (24) about the second axis of rotation (19). The widths of the grooves (18) allow the pins (17) to move within the respective corresponding grooves (18) in rotational direction about the second axis of rotation (19) under operating conditions. The relative position of the shaft (3) and the barrel plate (15) in rotational direction about the second axis of rotation (19) is adapted such that under operating conditions each centreline (22) of the respective barrel plate ports (21) fluctuates in rotational direction about the second axis of rotation (19) with respect to the centreline (23) of the corresponding sleeve opening (14) within a range in which the centreline (23) of the sleeve opening (14) lies.