Abstract: In a swash-plate type hydrostatic piston engine, a drive unit (10) and a swash plate (17) are received by a pot-shaped housing (1b). According to the invention, the pot-shaped housing (1b) is configured such that it is able to receive drive units (10a, 10b) of at least two rated quantities of a specific product series of the hydrostatic piston engine.

Abstract: The invention relates to a drive (1) having an energy storage device and a method for storing brake energy. A drive (1) has an energy storage device having a hydrostatic piston engine (9) and a storage element (11) which is connected thereto. In a high-pressure storage line (10), an adjustable throttle location (15) is arranged between the piston engine (9) and the storage element (11). During the braking operation, the adjustable throttle location (15) is adjusted in accordance with a detected requested brake torque. The pressure medium is conveyed from the hydrostatic piston engine (9) via the adjustable throttle location (15) into the storage element (11).

Abstract: A hydrostatic piston machine with a cylinder drum, which is rotatably mounted in a housing, is provided. A plurality of cylinder bores are disposed in the cylinder drum, which bores can be connected via cylinder openings provided in the cylinder drum to a first control opening and a second control opening. The first control opening is connected to a low-pressure line and the second control opening to a high-pressure line. The first control opening is connected via a first connection and a second connection to a channel, wherein the first connection and, lying opposite, the second connection are disposed at the first control opening.

Abstract: A pressure limiting valve comprises a valve closing body (7) which comprises a valve closing surface (8) which together with a first valve seat (9) opposing the valve closing surface (8) forms a first seal seat and a valve closing body orifice (11), which is surrounded by a second valve seat (12) which together with a closing head (14) configured on an axially displaceable valve bolt (13) forms a second seal seat and with a spring plate (15) which is connected to the valve bolt (13) and axially displaceable therewith, and a first return spring (10) clamped between the spring plate (15) and the valve closing body (7), which pretensions the valve bolt (13) against the second valve seat (12) configured on the valve closing body (7) and a second return spring (35) which pretensions a valve unit (7, 13, 15, 10) against the first valve seat (9). In the valve bolt (13) a longitudinal bore (53) is provided extending over the entire axial length of the valve bolt (13).

Abstract: The invention relates to a drive (1) having an energy recovery function. The drive having an energy recovery function comprises a hydrostatic piston machine (9) and at least one storage element (13) which is connected to said hydrostatic piston machine. Said hydrostatic piston machine (9) and the at least one storage element (13) are connected together by means of a storage line. Said storage line is divided into a first storage line section (11) and into a second storage line section (12) by a throttle value unit (15). Said throttle valve unit (15) comprises a control pressure valve unit (16) and a built-in valve (17). The control pressure valve unit (16) produces a control pressure which acts upon the built-in valve (17).

Abstract: An axial piston machine is provided. A housing of the machine receives an eccentric disk and a rotatably mounted cylinder drum. The drum has cylinders and pistons. The pistons are reciprocatable in the cylinders. The ends of the cylinders project from the cylinders and are supported via sliding blocks against a sliding surface on the eccentric disk. The sliding blocks are held in abutment with the sliding surface through a holding-down device. A pressure prevailing in a pressure chamber under the sliding blocks by a throttle point partially compensates a force that is exerted by the holding-down device on the sliding blocks, through a hydraulic pressure between an annular seating surface of the sliding blocks and a support surface of the holding-down device.

Abstract: The invention relates to an apparatus (1) and a method for the condition-dependent maintenance of hydrostatic displacement units (2), in particular axial piston machines (3) operated as pumps or motors. Mounted on the hydrostatic displacement unit (2) are acceleration sensors (4) and/or contamination level sensors (5) which capture vibration data and/or contamination data of the hydrostatic displacement unit (2) and are connected to an evaluation unit (6) which temporarily stores the vibration data and/or contamination data. A communication unit (7) connected to the evaluation unit (6) retransmits said data.

Abstract: An axial piston machine of swashplate construction is provided. The axial piston machine has two pivot bearing parts. In order to improve the guiding of a cage segment mounted within a gap between the two pivot bearing parts, a guide element, in the region of its rotary bearing connected to the cage segment is displaceably connected to the cage segment by an elongated guide in a longitudinal direction. The guide member, in the region of its end region connected to the other pivot bearing part, is rotatable by an associated rotary bearing and rigidly connected in the longitudinal direction to one of the two pivot bearing parts.

Abstract: A hydrostatic drive with first and second hydraulic pumps and a dual-acting hydraulic cylinder. The dual-acting hydraulic cylinder has a first working chamber defined by a first piston surface and a second working chamber defined by a second piston surface. The first working chamber is connected to first connections of the first and second hydraulic pumps. The second working chamber is connected to a second connection of the second hydraulic pump. A second connection of the first hydraulic pump is connected to a hydraulic fluid reservoir. The ratio of the first piston surface to the second piston surface differs from the ratio of the total delivery volume of the two hydraulic pumps relative to the delivery volume of the second hydraulic pump. A tapping valve for removing hydraulic fluid is provided for the volumetric flow equalisation.

Abstract: The invention concerns a method and a transmission arrangement for changing gears in a transmission with a hydrostatic transmission and a manual gearbox (4) connected downstream from it. First the output torque of a hydrostatic motor (9) is reduced. After the reduction of the output torque of the hydrostatic motor (9), an engaged gear (12, 13) of the manual gearbox (4) which is connected downstream is disengaged. An output rotational speed of the hydrostatic motor (9) corresponding to the gear (13, 12) to be engaged is determined. The gear ratio of the hydrostatic transmission is then adjusted, so that the output rotational speed of the hydrostatic motor (9) is higher than the determined corresponding output rotational speed. After this increased output rotational speed is reached, the gear (13, 12) to be engaged is engaged.

Abstract: A regulating device for a hydrostatic piston engine is provided. The regulating device (30) has an electronic control unit (17) for generating adjusting signals. An adjusting position of the hydrostatic piston engine scanned by a feedback element (36, 61) is detected by a sensor element (42) of the electronic control unit (17) without contact.

Abstract: The invention relates to an axial piston machine, in addition to a swash-plate for said machine and a method for producing a swash-plate. The swash-plate (24) is configured as a disc and has a central bore (32), which is encompassed by a collar (39), extending in an axial direction from a first surface (34, 34?) of the swash-plate (24). In addition, the swash-plate (24) has several sliding block receiving openings (36), each of the latter (36) being encompassed by a guide collar (38), which extends in an axial direction from a second surface of the swash-plate (24), in the opposite direction to the collar (39) of the central bore (32).

Abstract: The invention related to a hydrostatic drive comprising a hydraulic pump (3) which is driven by a drive machine (2) and pumps into at least one first working line (4), and a pressure line (18) in which a feed quantity dependent on the speed of the drive machine (2) flows. When a differential pressure value in the pressure line (18) is exceeded, the pressure means can be extracted from the first working line (4).

Abstract: The invention relates to a hydrostatic drive (1) comprising at least one first hydraulic pump (4), a second hydraulic pump (5), and first, a second, a third, and a forth hydraulic motor (7, 8, 9, 10). A first connection (12) of the first hydraulic pump (4) is connected to a first connection (19) of the first hydraulic motor (7) and a first connection (20) of the third hydraulic motor (9). A first connection (16) of the second hydraulic pump (5) is connected to a first connection (26) of the second hydraulic motor (8) and a first connection (27) of the fourth hydraulic motor (10). A second connection (22) of the first hydraulic motor (7) and a second connection (29) of the fourth hydraulic motor (10) are connected to a second connection (18) of the second hydraulic pump (5). A second connection (28) of the second hydraulic motor (8) and a second connection (23) of the third hydraulic motor (9) are connected to a second connection (14) of the first hydraulic pump (4).

Abstract: The invention relates to a device (1) for state monitoring in hydrostatic displacement units (2), in particular in axial piston machines (3) operated as a pump or as a motor. The device (1) comprises an acquisition unit (4) with a multiplicity of sensors (5) which are attached to the hydrostatic displacement unit (2) and serve to acquire monitoring data (6) and operating data (7), and an evaluating unit (8) which has a device (9) for analysing the monitoring data in the frequency range and a device (10) for analysing the monitoring data in the time range. A diagnostic unit (11) with an output unit (13) is connected to the evaluating unit (8).

Abstract: The invention relates to a hydraulic drive, comprising a hydraulic cylinder (1), divided into a first operating pressure chamber (4) and a second operating pressure chamber (5), by an operating piston (3). The hydraulic drive further comprises a closed hydraulic circuit (39), with a first hydraulic pump (43), connected to the first operating pressure chamber (4) via a first working line (7), by means of a first connector (10) and to the second operating pressure chamber (5) via a second working line (13), by means of a second connector (12). In addition, an open hydraulic circuit (40) is provided, with a second hydraulic pump (8), connected to the first operating pressure chamber (4), by means of a third connector (11). A fourth connector (14) on the second hydraulic pump (8) is connected to a hydraulic reservoir element (75).

Abstract: Disclosed is a hydraulic steering system (100) for a vehicle, especially a mobile working machine, comprising at least two steering cylinders (1, 2) within which two cylinder pistons (3, 4) can be displaced, and a first hydraulic pump (14) that can be adjusted regarding the swept volume. The position or the direction of displacement of the cylinder pistons (3, 4) in the steering cylinders (3, 4) defines the steering angle or the steering direction of the steerable vehicle wheels relative to a body (5) of the vehicle. The displaceable cylinder pistons (3, 4) divide the associated steering cylinder (1, 2) into two respective pressure chambers (6 and 7, 8 and 9).

Abstract: The invention relates to a drive (1) having an energy storage device and a method for storing brake energy. A drive (1) has an energy storage device having a hydrostatic piston engine (9) and a storage element (11) which is connected thereto. In a high-pressure storage line (10), an adjustable throttle location (15) is arranged between the piston engine (9) and the storage element (11). During the braking operation, the adjustable throttle location (15) is adjusted in accordance with a detected requested brake torque. The pressure medium is conveyed from the hydrostatic piston engine (9) via the adjustable throttle location (15) into the storage element (11).

Abstract: A hydraulic steering system (1) including a hydraulic steering unit (2) and an auxiliary device (3). Said The steering unit (2) feeds a hydraulic medium to a steering cylinder (5) according to the movement of a steering wheel (4). The auxiliary device (3) includes a valve unit (6) and also feeds a hydraulic medium to the steering cylinder (5) according to the movement of the steering wheel (4), in order to assist the steering movement. The hydraulic medium ejected or discharged from the steering cylinder (5) as a result of the hydraulic medium fed thereinto flows back into a tank (10) or to a pump (8, 9) through the steering unit (2).

Abstract: The invention relates to a method for braking a vehicle, driven by means of a hydrostatic gearbox (28) and a hydrostatic drive. The hydrostatic gearbox (28) comprises at least one adjustable hydrostatic motor (6,6). The vehicle driven by means of the hydrostatic gearbox (28) may be retarded by an operating brake. On recognition of a certain braking process, the hydraulic motor (6,6) is adjusted to a minimal pivot angle. On recognition of a termination of the certain braking process, the hydraulic motor (6,6) is adjusted to a pivot angle which matches the speed achieved after the braking process.