Abstract: A pump arrangement (1) is provided comprising a driving shaft (2), cylinder drum means (3a, 3b) fixed to said shaft (2) in rotational direction and having a plurality of cylinders (6a, 6b), and a piston (7a, 7b) in each cylinder, each piston (7a, 7b) having a slide shoe (8a, 8b) in contact with driving surface means (8a, 8b). Such a pump arrangement should produce a pressure with low undulations. To this end said cylinder drum means (3a. 3b) comprise at least a first cylinder drum (3a) and a second cylinder drum (3b), said cylinder drums (3a, 3b) being fixed to said common shaft (2) in rotational direction, wherein the cylinder drums (3a, 3b) are offset with respect to each other in rotational direction.

Abstract: A hydraulic machine is provided comprising a cylinder unit (3) having a plurality of cylinders (4a, 4b) which are located on a circle line around an axis of rotation of said cylinder unit (3), a valve plate (6) located at an axial end of said cylinder unit (3) and having a through-going opening (8) for each cylinder (4a, 4b), and a port plate, said valve plate (6) and said port plate resting against each other in sliding contact at a contact face, wherein a pressure in each cylinder (4a, 4b) acts on a pressure area on a side of said valve plate (6) opposite said port plate. In such a hydraulic machine the risk of leaking should be kept small. To this end said pressure area (17) deviates from a circular form.

Abstract: A hydraulic machine is described comprising a first part (1, 4) and a second part (7, 8), wherein the first part (1, 4) and the second part (7. 8) are movable relatively to each other in abutting relation, the first part (1, 4) comprises a pressure chamber (2) having a pressure chamber opening (6) in a contact face (5) contacting a sealing face (9) of the second part (7, 8), the second part (7, 8) comprises a low pressure area (10) connected to a low pressure opening (11) in the sealing face (9) and a high pressure area (12) connected to a high pressure opening (13) in the sealing face (9), wherein during a movement of the first part (1, 4) with respect to the second part (7, 8) in a moving direction (14) the pressure chamber opening (6) comes alternatingly in overlap with the low pressure opening (11) and the high pressure opening (13). Such a machine should be flexible in operation with low risk of damages caused by cavitation. To this end a throttling channel (15) in the second part (7.

Abstract: A vane cell machine (1) is described comprising a stator (2) and a rotor (3), said rotor (3) having radially displaceable vanes (4) bearing on an inside (5) of the stator (2) and bordering, together with the rotor (3), the stator (2), and a side wall (7) at each axial end of the rotor (3), work chambers (6) the volume of which changes during a rotation of said rotor, at least one side wall (7) bearing an insert in form of a ring (9). Such a machine should be of simple construction. To this end, said ring (9) comprises a centric bore (10).

Abstract: A hydraulic machine arrangement (1) is described having a housing (5), a working section and a hollow inside said housing (5), a supply port arrangement LPin, HPin, LPout connected to said working area, and a leakage path (7) between said working section and said hollow. It should be possible to detect wear with simple means. To this end, said housing (5) is provided with a leakage port (8) connected to said hollow.

Abstract: A hydraulic arrangement (1) is provided comprising a pressure exchanger (2) having an axis (3) of rotation, and a booster pump (4), said pressure exchanger (2) and said booster pump (4) being connected to each other. Such a hydraulic arrangement should have a good efficiency. To this end a single connection flange (5) is provided between said pressure exchanger (2) and the booster pump (4).

Abstract: An axial piston machine (1) is shown, comprising: a shaft (2) having an axis (3) of rotation, a cylinder drum (4) connected to said shaft (2) and having at least a cylinder (5) parallel to said axis (3) of rotation, a piston (6) movable in said cylinder (5), a swash plate (13), a slide shoe (11) pivotally mounted to said piston (6), and holding means holding said slide shoe (11) against said swash plate (13), said holding means having a pressure plate (14) and a number of coil springs (15) arranged between said cylinder drum (4) and said pressure plate (14). The object is to have a reliable operation of said machine with a simple construction. To this end each coil spring (15) is at least at one end fixed by a protrusion (20) extending into said coil spring (15).

Abstract: An axial piston machine is shown comprising a cylinder drum rotatable around an axis of rotation and having at least a cylinder, a piston arranged in said cylinder, a swash plate arranged in front of said cylinder drum, said piston being provided with a slipper (11) resting against said swash plate and having a pressure area (17) on a side facing said swash plate, wherein a cylinder axis of said cylinder is arranged on a circle line (27) around said axis of rotation (16). Such a machine should be made compact. To this end said pressure area (17) deviates from a circular form.

Abstract: A hydraulic machine arrangement (1) is described having a housing (5), a working section and a hollow inside said housing (5), a supply port arrangement LPin, HPin, LPout connected to said working area, and a leakage path (7) between said working section and said hollow. It should be possible to detect wear with simple means. To this end, said housing (5) is provided with a leakage port (8) connected to said hollow.

Abstract: A water-hydraulic machine (1) is disclosed with at least two parts which are movable relative to one another, of which one has a surface composed of a plastic (5, 12, 13, 15, 19) with friction-reducing properties. With such a design the wear in case of a water-hydraulic machine should be kept low. To this end, the plastic (5, 12, 13, 15, 19) is formed as a polymer with ceramic filler.

Abstract: A hydraulic machine is described having a first part (2) and a second part (3) moveable relative to said first part (3), one of said first part (2) and said second part (3) having a first land (9) resting against the other one of said second part (3) and said first part (2), having a predetermined first height (H1), and being arranged between a high pressure area (7) and a low pressure area (8). Such a machine should have a long working life. To this end a second land (10) having a predetermined second height (H2) smaller than said first height (H1) is located adjacent to said first land (9).

Abstract: A vane cell machine (1) is described comprising a stator (2) and a rotor (3), said rotor (3) having radially displaceable vanes (4) bearing on an inside (5) of the stator (2) and bordering, together with the rotor (3), the stator (2), and a side wall (7) at each axial end of the rotor (3), work chambers (6) the volume of which changes during a rotation of said rotor, at least one side wall (7) bearing an insert in form of a ring (9). Such a machine should be of simple construction. To this end, said ring (9) comprises a centric bore (10).

Abstract: A hydraulic machine is provided comprising a cylinder unit (3) having a plurality of cylinders (4a, 4b) which are located on a circle line around an axis of rotation of said cylinder unit (3), a valve plate (6) located at an axial end of said cylinder unit (3) and having a through-going opening (8) for each cylinder (4a, 4b), and a port plate, said valve plate (6) and said port plate resting against each other in sliding contact at a contact face, wherein a pressure in each cylinder (4a, 4b) acts on a pressure area on a side of said valve plate (6) opposite said port plate. In such a hydraulic machine the risk of leaking should be kept small. To this end said pressure area (17) deviates from a circular form.

Abstract: A hydraulic arrangement (1) is provided comprising a pressure exchanger (2) having an axis (3) of rotation, and a booster pump (4), said pressure exchanger (2) and said booster pump (4) being connected to each other. Such a hydraulic arrangement should have a good efficiency. To this end a single connection flange (5) is provided between said pressure exchanger (2) and the booster pump (4).

Abstract: An axial piston machine is shown comprising a cylinder drum rotatable around an axis of rotation and having at least a cylinder, a piston arranged in said cylinder, a swash plate arranged in front of said cylinder drum, said piston being provided with a slipper (11) resting against said swash plate and having a pressure area (17) on a side facing said swash plate, wherein a cylinder axis of said cylinder is arranged on a circle line (27) around said axis of rotation (16). Such a machine should be made compact. To this end said pressure area (17) deviates from a circular form.

Abstract: A pump arrangement (1) is provided comprising a driving shaft (2), cylinder drum means (3a, 3b) fixed to said shaft (2) in rotational direction and having a plurality of cylinders (6a, 6b), and a piston (7a, 7b) in each cylinder, each piston (7a, 7b) having a slide shoe (8a, 8b) in contact with driving surface means (8a, 8b). Such a pump arrangement should produce a pressure with low undulations. To this end said cylinder drum means (3a. 3b) comprise at least a first cylinder drum (3a) and a second cylinder drum (3b), said cylinder drums (3a, 3b) being fixed to said common shaft (2) in rotational direction, wherein the cylinder drums (3a, 3b) are offset with respect to each other in rotational direction.

Abstract: An axial piston machine (1) is shown, comprising: a shaft (2) having an axis (3) of rotation, a cylinder drum (4) connected to said shaft (2) and having at least a cylinder (5) parallel to said axis (3) of rotation, a piston (6) movable in said cylinder (5), a swash plate (13), a slide shoe (11) pivotally mounted to said piston (6), and holding means holding said slide shoe (11) against said swash plate (13), said holding means having a pressure plate (14) and a number of coil springs (15) arranged between said cylinder drum (4) and said pressure plate (14). The object is to have a reliable operation of said machine with a simple construction. To this end each coil spring (15) is at least at one end fixed by a protrusion (20) extending into said coil spring (15).

Abstract: A pump device (1) is provided comprising: a shaft (2), rotor means (3a, 3b) fixed to said shaft (2) in rotational direction, said rotor means (3a, 3b) having pressure chambers (5a, 5b) the volume of which varying during a rotation of said rotor means (3a, 3b), port plate means (15a, 15b) having a through going opening (16a, 16b) for each of said pressure chambers (5a, 5b) and being connected to said rotor means (3a, 3b) in rotational direction, and valve plate means (17a, 17b) cooperating with said port plate means (15a, 15b). It is intended to pressurize a high volume of fluid, in particular water, within a limited space.