Abstract: The invention concerns a hydraulic valve arrangement (1) with a supply connection arrangement comprising a high-pressure connection (P) and a low-pressure connection (T), a working connection arrangement comprising two working connections (A, B), which can be connected to a motor (4), a directional valve arrangement (5) located between the supply connection arrangement (P, T) and the working connection arrangement (A, B), and a compensation valve (15) acted upon in a first activation direction by a pressure in a first pressure chamber (33), which is connected to a load-sensing pipe (LS), and, if required, by a spring (32), and in a second activation direction opposite to the first activation direction by a pressure downstream of the directional valve arrangement (5), said pressure acting in a second pressure chamber (34), the compensation valve (15) having an inlet (14) and an outlet (19).

Abstract: A variable displacement bent axis unit comprising a housing and a yoke pivotally disposed therein wherein the yoke has a cam member attached thereto. A control mechanism that changes the displacement of the unit has a control valve disposed therein that engages the cam member. The cam member itself has a non-linear feedback profile such that the feedback profile provides a linearized speed ratio.

Abstract: The invention concerns a hydraulic machine with a set of teeth, having a toothed ring with an inner toothing and a gear wheel with an outer toothing, the gear wheel rotating and orbiting in the toothed ring, the inner toothing and the outer toothing touching each other in contact areas, thus separating pressure chambers, and with a valve arrangement controlling a connection between a connection arrangement having a high pressure connection and a low pressure connection, and the pressure chambers. It is endeavoured to achieve a stable operation, particularly with low speeds. For this purpose, each contact area is provided with an opening, which, at the time when a pressure chamber reaches an extreme value of its volume, produces a short-circuiting with the neighbouring pressure chamber.

Abstract: The invention concerns a hydraulic valve arrangement (1) having at least two working connections (A, B), a check valve (5, 6) being allocated to each working connection (A, B), and a pressure relief valve (7, 8) being allocated to each check valve (5, 6), each pressure relief valve (7, 8) being connected to a control pressure passage (17, 18). The valve arrangement shall ensure a reliable, pressure-less lowering, also in connection with single-actuated consumers, and further enable a pressure-less float position. For this purpose, the check valves (5, 6) can be opened by means of tappets (20, 21), whose sides facing away from the check valves (5, 6) are ending in a pressure chamber (22), which is connected to the control pressure passage (17, 18) of one of the pressure relief valves (7, 8).

Abstract: Hydraulic system with a hydraulic machine, in particular an axial piston or radial piston unit, with rotating and moving machine components which are arranged in a housing. The housing is connected to a high-pressure and a low-pressure line of a working circuit, which is supplied with pressure fluid by means of a charge pump. The leakage fluid which occurs in the housing collects in a leakage fluid reservoir which is arranged below the rotating and moving hydraulic machine components in the working position of the hydraulic machine and is connected fluidically to the housing. The leakage fluid is pumped out of the leakage fluid reservoir into the low-pressure line of the working circuit by the charge pump.

Abstract: The invention relates to a hydraulic pump or hydraulic motor having an orbiting cardan shaft. The hydraulic pump or motor includes a housing having an end cover and a port plate. The cardan shaft is mounted in the housing and extends through the port plate. A rotation speed sensor is fixed to the port plate and includes a sensor probe obtaining its signal from the orbiting cardan shaft. A piston may be in contact with the cardan shaft and moving forward and back due to the orbital motion of the cardan shaft. The sensor probe then obtains its signal from the movement of the piston.

Abstract: A method of operating a transmission of a vehicle. The method includes determining an open loop ratio percentage from an engine RPM input signal and a brake input signal using a first algorithm. Determining a closed loop ratio percentage from the engine RPM input signal, a vehicle RPM input signal and a throttle input signal using a second algorithm. Summing the open loop percentage and closed loop ratio percentage to calculate a ratio command percentage that is used to sum with a swashplate input to actuate a swashplate positioner and operate the transmission.

Abstract: The invention concerns a hydraulic steering (1) with a steering unit (2) with feedback behaviour, a steering motor (8) connected to the steering unit (2) via working pipes (L, R), a steering member (6) and a feedback suppression device (9), which is located in at least one working pipe (L, R). It is endeavoured to change the feedback behaviour of such a steering in a simple manner. For this purpose, the feedback suppression device (9) has a valve arrangement (10) with hydraulic control inlet (C).

Abstract: If a hydraulic system has several modes of operation, in particular a mode with a high pressure demand (II) and a mode with a high fluid flow demand (II), the hydraulic fluid pump has to be built with an accordingly high fluid flow output. Such a pump is expensive. Therefore it is suggested, to provide two pumps. I.e. a controllable main pump (2) is provided, which supplies the hydraulic consumer (6) during phases (I) of high pressure demand. During phases (II) of high fluid flow demand, normally, relatively low pressures are sufficient. Therefore, it is suggested to provide a parallel boost pump (9), which supplies the hydraulic consumer (6) in addition to the high pressure pump (2), if a high fluid flow is needed. Excess fluid flow output is avoided by controlling the fluid output flow of main pump 2.

Abstract: A valve assembly (2) forming a bridge circuit and a hydraulic actuator comprising at least one valve assembly (2) are disclosed. The valve assembly (2) is fluidly connectable between a fluid source (3) and a fluid drain (4). The valve assembly (2) comprises a first valve (8) fluidly connected between the fluid source (3) and a first diagonal point (12) of the bridge circuit, a second valve (9) fluidly connected between the fluid source (3) and a second diagonal point (13) of the bridge circuit, a third valve (10) fluidly connected between the first diagonal point (12) and the fluid drain (4), and a fourth valve (11) fluidly connected between the second diagonal point (13) and the fluid drain (4). The valves (8, 9, 10, 11) are such that in the case of a power cut off, flows of fluid away from the diagonal points (12, 13) are prevented.

Abstract: When the fluid flow output of a synthetically commutated hydraulic pump is adapted to a given fluid flow demand, pulsations in the fluid output flow of the synthetically commutated hydraulic pump can occur. To avoid such pressure pulsations, it is suggested, to use a set of pre-calculated actuation patterns for actuating the electrically commutated valves of the synthetically commutated hydraulic pump.

Abstract: A fluid working machine (1) has several working chambers (5) of cyclically changing volume. For pumping hydraulic fluid, the inlet and outlet valves (8, 9) are electrically actuated. The timing of the actuation of said electrically actuated valves (8, 9) is varied depending on the fluid flow demand.

Abstract: To improve the fluid output flow characteristics (14) of a synthetically commutated hydraulic pump (1), it is suggested to use a plurality of different valve (10) actuation strategies. For every fluid flow demand region I to VI a certain actuation strategy is chosen.

Abstract: The invention relates to a hydraulic drive (2) having a main pump (8), which can be adjusted in terms of delivery volume and delivery direction, and having a hydraulic motor (9), which main pump (8) and hydraulic motor (9) are connected to one another in a closed circuit via pressure lines (10A, 10B), and having a charge pump (14, 15) for charging into the closed circuit and for supplying pressurized fluid to at least one controling device (11, 12), wherein the charge pump (15) has a separate drive motor (19) whose power/rotational speed can be specified independently of the rotational speed of the drive (3) of the main pump (8). In this way, the charge pump (15) can be of smaller dimensions than previously conventional, and the power balance of the hydraulic drive can be improved.

Abstract: An axial piston hydraulic machine having a housing with a cylinder block with reciprocating pistons disposed therein. The reciprocating pistons are rotatably connected to a swashplate at a first end of the swashplate. At a second end of a swashplate support balls are received and engage the housing. The support balls are located radially from the plurality of reciprocating pistons such that the distance between the axis of rotation of an input shaft and a piston axis of the plurality of pistons is significantly less than the radial distance between the axis of rotation of the shaft and the center points of the support balls, and wherein the pivot axis passing through the center points of the support balls lies in or near the plane passing through the piston/slipper ball joints.

Abstract: The invention concerns a hydraulic steering (1) with a steering unit (2) with feedback behavior, a steering motor (8) connected to the steering unit (2) via working pipes (L, R), a steering member (6) and a feedback suppression device (9), which is located in at least one working pipe (L, R). It is endeavored to change the feedback behavior of such a steering in a simple manner. For this purpose, the feedback suppression device (9) has a valve arrangement (10) with hydraulic control inlet (C).

Abstract: The invention concerns a hydraulic valve arrangement (1) with several valve modules (2-6), each having a supply channel arrangement with a high-pressure channel (7) and a low-pressure channel (8), a working connection arrangement with at least one working connection (A, B), a directional valve arrangement (15, 16) between the supply channel arrangement and the working connection arrangement and a compensation arrangement (19, 28). It is endeavoured to improve the control possibilities. For this purpose, it is provided that in at least one valve module (3, 5) the compensation arrangement is a pre-compensation arrangement (19) and in at least one other valve module (4, 6) the compensation arrangement is a post-compensation arrangement (28).

Abstract: The invention concerns a hydraulic steering with a steering motor arrangement having at least one steering motor, and with at least two steering circuits, each having a steering valve that interrupts a path from a pressure supply to the steering motor arrangement in the neutral position and releases a path from the pressure supply to the steering motor arrangement on a movement out of the neutral position. It is endeavored to simplify the embodiment of such a steering. For this purpose, the steering valve (5a, 5b) has two end positions, one on each side of the neutral position, in which positions a path from the pressure supply (15, 21) to the steering motor arrangement (2) is interrupted.

Abstract: An object comprising a body part having an electrically insulating outer surface part, and a first layer arranged on the outer surface part. The first layer is formed by one or more electrically conducting materials and defines one or more conducting paths between a first area of the outer surface part and a second area of the outer surface part. Thereby electrical signals may be transferred between the first and second area parts. The layer further defines a sensing device, which is thereby embedded into the object. The object is provided with a threaded portion defining an outer thread. Thereby the object may easily be fitted into an opening having a mating inner thread. The object may be in the form of an ordinary bolt with a sensing device embedded in a surface part thereof.

Abstract: A joystick device having a grip assembly pivotably connected to a base assembly. The base assembly having sensing elements that detect the movement of the grip assembly as it pivots about the base assembly. Disposed within the base assembly and the sensing elements is a microprocessor. The microprocessor verifies an output signal prior to transmitting to a remote controller.