Abstract: The invention relates to an axial piston engine with a filling pump integrated in a receiving bore of the axial piston engine, which filling pump comprises a gerotor set with an externally toothed inner ring and an internally toothed outer ring and also an inner thrust plate and an outer thrust plate. The two thrust plates enclose the gerotor set between them and, on their surfaces facing away from the gerotor set, are in each case supported via a pressure field seal, which surrounds the pressure field regions formed in the thrust plates, in such a way on the housing walls axially enclosing the filling pump that lateral play in the form of axial mobility of the filling pump is guaranteed.

Abstract: A vane-type fluid displacement unit having a housing, a drive shaft extending through the housing, a rotor secured to the drive shaft and disposed within the housing, the rotor having at least one non-smooth top or bottom surface, and at least one vane secured to the rotor.

Abstract: A hydraulic unit that uses first and second support structures to eliminate the use of webs within an arcuate inlet and outlet of a valve plate. Specifically, a valve plate body extends between an inner and outer diameter wherein the outer diameter in a first position is placed in close proximity to a first support structure and the inner diameter is placed in close proximity to a second support structure. Thus, stress of hydraulic fluid flowing through the arcuate inlet or outlet deflects the inner and outer diameters causing them to engage the first and second support structures such that stress is passed to the first and second support structures and the valve plate is stiffened.

Abstract: A joystick device is provided that is in electronic communication with a remotely located main electronic controller used to control heavy machinery and the like. The joystick device includes a base assembly having a first microprocessor in electronic communication with the main electronic controller. The joystick device also includes a grip assembly pivotally connected to the base assembly. The grip assembly includes a plurality of input buttons and a second microprocessor in electronic communication with the first microprocessor. The joystick device further includes sensing elements that detect movement of the joystick device.

Abstract: A gasket for a hydraulic housing and a method of manufacturing the same. The gasket is made by taking a metal body having a first and second side and coating the first and second side with rubber. An area of the rubber is then burned off by a laser and then in that area the laser is used to create a plurality of openings that act to filter hydraulic fluid that flows through the gasket.

Abstract: A relief valve assembly. The relief valve assembly has a housing that houses a sleeve element that surrounds a spool that has a spring guide disposed therein and is biased away from the spool by a spring. A fluid flow path is created from a valve exit of the assembly through the sleeve and spool via a series of openings, grooves and orifices in at least one position of the relief valve assembly. The fluid flow path acts to reduce pressure rise rate.

Abstract: A valve assembly for a hydraulic device. The valve assembly has a valve seat within a valve passageway used in combination with a spool. The spool has a first section wherein a flexible element is disposed within a cavity of the first section such that in a first position the spool and specifically the flexible element engages the valve seat to provide zero leakage from the valve passageway into a tank passageway. Additionally, the spool is designed to have an additional section at a second end to provide equal sealing areas at both the first and second ends of the spool to balance the forces within the valve passageway.

Abstract: A method of yielding the average current in a PWM driven coil for an electrohydraulic valve. The method includes transmitting a feedback signal into a Finite Impulse Response filter to take multiple signal samples in order to calculate and average value of current within one cycle. This average value is transmitted to an algorithm that generates a pulse width signal that drives the coil of the electrohydraulic valve in the next system cycle.

Abstract: An arrangement for filtering a hydraulic fluid having a bypass line connecting the feed channel to the discharge channel where the bypass line is opened by a pressure switching valve when a pressure change is caused by the contamination of the filter element.

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: The invention provides a method and a system for moving an element, e.g. a rudder of a ship or a wheel of a vehicle. The element is moved by a hydraulic fluid. According to the invention, an operator indicates a desired movement, and in accordance with the desired movement, at fluid is provided from at least three fluid providers each providing a share of the fluid in parallel streams and only considering the desired movement not the shares provided by the other fluid providers. The invention allows continuation of a steering task even if one fluid provider is disabled, and the invention allows the continuation even without having to notice that one provider is disabled. Accordingly, the invention provides an improvement and simplification relative to the known hydraulic steering systems.

Abstract: The invention provides a steering system e.g. for a vehicle. The system comprises a system-pump, a steering actuator, a rotary valve, a rotary meter, and a motor. The system-pump is arranged to provide a flow of a fluid to the steering actuator via the rotary valve and via the rotary meter, and the motor is arranged to provide rotation of the rotary valve and the rotary meter. To handle an emergency situation if the system-pump fails, the motor is dimensioned to operate the rotary meter as a fail-operational pump for pumping a flow of the fluid to the steering actuator if the system-pump fails.

Abstract: The invention concerns a hydraulic machine (1) with an externally toothed gear wheel (2) and an internally toothed ring (3), which is made of a sintered material or of a ceramic material. It is endeavored to provide good operation behaviour at low costs. For this purpose, the toothed ring (3) is provided with a sealing element (7) in the area of its outer circumference.

Abstract: A joystick (1) comprising a substantially stationary part (4) and a movable part (3) adapted to be manipulated by an operator. The joystick further comprises a sensor device adapted to detect a position of the movable part (3) relatively to the substantially stationary part (4), the sensor device comprising a magnet arrangement comprising one or more magnets (9) and defining a predetermined magnetic field, and a magnetic detector being adapted to detect a magnetic flux and to generate a corresponding output. The magnet arrangement or the magnetic detector is arranged on the substantially stationary part (4), while the magnetic detector or the magnet arrangement is arranged on the movable part (3). Thereby relative movements between the parts (3, 4) result in relative movements between the magnet arrangement and the magnetic detector.

Abstract: A method of calibrating a valid operating range. The method includes loading a default calibration limit and then monitoring an input for new calibration limits provided by an input device. An algorithm then detects if the new calibration limits provide a fault and if not the algorithm rescales the output based upon the new calibration limits to increase the valid operating range.

Abstract: The invention concerns a hydraulic valve arrangement (1) with at least two valve modules (2-6), each having a supply channel arrangement with a high-pressure channel (9) and a low-pressure channel (15), a working connection arrangement with at least one working connection (A, B), one directional valve arrangement (16) between the supply channel arrangement (9, 15) and the working connection arrangement (A, B) and a compensation arrangement (19), which is acted upon by a pressure in a load-sensing arrangement. It is endeavoured to increase the number of control possibilities. For this purpose, the load-sensing arrangement of at least one valve module (2-6) has a pressure influencing arrangement (25-29) that differs from a pressure influencing arrangement (25-29) of a load sensing arrangement of another valve module (2-6).

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: A hydraulic actuator for a hydraulic servomotor (4) is disclosed. The hydraulic servomotor (4) is of a kind having at least one defined end position, and has a first chamber (5) and a second chamber (6) associated therewith. The actuator is connected to a fluid source (2) and a fluid drain (3). The actuator comprises a first valve (7) fluidly connected between the fluid source (2) and the first chamber (5), a second valve (8) fluidly connected between the first chamber (5) and the fluid drain (3), and a third valve (9) fluidly connected between the fluid source (2) and the second chamber (6). The actuator further comprises a flow channel (10, 17), preferably comprising a flow restrictor (12, 18), in fluid communication with the second chamber (6). The valves (7, 8, 9) are such that, in the case of a power cut off, they will prevent a fluid flow out of the first chamber (5), and a fluid flow out of the second chamber (6) takes place via the flow channel (10, 17).