A piston pump includes: a tilting mechanism configured to bias a swash plate in accordance with a control pressure; a support spring configured to support the swash plate; and a regulator configured to control a control pressure guided to the tilting mechanism in accordance with a self-pressure of the piston pump. The regulator has an outer spring and an inner spring configured to be extended and compressed by following tilting of the swash plate; and a control spool configured to be moved in accordance with a biasing force from the outer spring and the inner spring, the control spool being configured to regulate the control pressure, and the outer spring and the inner spring and the support spring are provided adjacent to each other and in parallel with respect to the swash plate.

A hydraulic machine with oscillating axial cylinders includes a plurality of oscillating axial cylinders, put in synchronous rotation between a first rotating element, a rotating disc, which supports one end of the cylinder, bottom or piston, and a second rotating element, a rotating barrel, which supports the opposite end of the cylinder; each cylinder is connected to said rotating elements with a ball joint towards each of them; each ball joint is holed to allow for the passage and the feeding/discharge through it of the hydraulic liquid. At least the bottom or the piston is connected to the respective rotating element with a ball joint having a spherical surface with a diameter equal to or greater than the cylinder bore.

A piston pump includes: a tilting mechanism configured to bias a swash plate in accordance with a control pressure; a support spring configured to support the swash plate; and a regulator configured to control a control pressure guided to the tilting mechanism in accordance with a self-pressure of the piston pump. The regulator has an outer spring and an inner spring configured to be extended and compressed by following tilting of the swash plate; and a control spool configured to be moved in accordance with a biasing force from the outer spring and the inner spring, the control spool being configured to regulate the control pressure, and the outer spring and the inner spring and the support spring are provided adjacent to each other and in parallel with respect to the swash plate.

A device, system, and process for turning hydraulic pressure into rotational force and for turning rotational motion into hydraulic pressure. An example of the device/system for performing the process comprises actuators, rotationally positioned between two thrust plates that are fixed in a housing at an angle to a rotational axis and in parallel to each other.

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.

A device, system, and process for turning hydraulic pressure into rotational force and for turning rotational motion into hydraulic pressure. An example of the device/system for performing the process comprises actuators, rotationally positioned between two thrust plates that are fixed in a housing at an angle to a rotational axis and in parallel to each other.

A control plate, for alternatingly fluidically connecting hydrostatic operating chambers, in particular of an oblique axis type axial piston machine, with pressure medium connections, includes a first end face, a second end face, at least a first recess, a first kidney-like control opening, and at least one through-recess. The first face extends transversely to a rotation axis. The second face faces away from the first face. The first recess is bounded in the first end face by the first control opening, and at least partially forms the at least one through recess, which extends toward the second end face from the first end face at an end portion of the first control opening, and which is arranged in or counter to a rotation direction of the rotation axis. An oblique axis construction type axial piston machine includes such a control plate.

A device, system, and process for turning hydraulic pressure into rotational force and for turning rotational motion into hydraulic pressure. An example of the device/system for performing the process comprises actuators, rotationally positioned between two thrust plates that are fixed in a housing at an angle to a rotational axis and in parallel to each other.

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.

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).