A monitoring device for determining at least one position of a displacement piston (1) which is guided longitudinally movably in a housing (7) and, in the housing (7), delimits at least one fluid chamber (3, 5) with a variable volume, which fluid chamber (3, 5) is connected via a pressure supply connector (9, 11) to a pressure fluid control device (13), is characterized in that a volumetric flow regulating device (45) and, following the latter in the direction of the measuring connector (15, 17), a pressure determining device (47) are connected between the pressure fluid control device (13) and the measuring connector (15, 17) of the assignable fluid chamber (5, 3) of the displacement piston (1), which pressure determining device (47) outputs a measuring signal at least when the displacement piston (1) has reached a predefined end position in the housing (7).

A work implement has a boom, an arm, and a bucket pivotable around a bucket axis which is a pivot axis with respect to the arm and a tilt axis orthogonal to the bucket axis. The hydraulic cylinder has the bucket pivot around the tilt axis. The regulation valve regulates an amount of supply of a hydraulic oil to be supplied to the hydraulic cylinder based on a command signal. The position sensor measures a stroke length of the hydraulic cylinder. The control unit resets the stroke length measured by the position sensor. The control unit determines proximity to a stroke end of the hydraulic cylinder, generates a command signal for increasing a degree of opening of the regulation valve in the proximity of the stroke end, and resets the stroke length measured by the position sensor while the regulation valve is open in response to the command signal.

A pneumatic control device includes a functional assembly that has an interruption valve device for the selective opening or interruption of at least one main working channel used for the pneumatic control of a pneumatic actuator. The functional assembly also contains a manually actuatable valve device that is connected to the interruption valve device by means of at least one auxiliary working channel and which enables manual pneumatic control of the connected actuator, if the at least one main working channel is interrupted by the interruption valve device at the same time. A process control device can also be equipped with a control device of this type.

A fluid power control system for load handling mobile equipment includes a pair of hydraulic actuators for moving respective cooperating load-engaging members selectively toward or away from each other, or in a common direction, at respective asynchronous speeds to selectively attain either synchronous or asynchronous respective positions of the actuators. The actuators have sensors enabling a controller to monitor their respective movements and correct unintended differences in the actuators' respective movements, such as unintended differences in relative intended positions, speeds, or rates of change of speeds. Respective hydraulic valves responsive to the controller separately and nonsimultaneously decrease respective flows through the respective actuators to more accurately and rapidly correct differences from the intended relative movements of the actuators.

The present disclosure provides a control valve assembly arranged between a main control valve and a hydraulic function on a mobile machine. The control valve assembly includes a fluid source, a first supply valve, a first return valve, a second supply valve, and a second return valve. The control valve assembly further includes a controller configured to determine if an actual motion parameter of the hydraulic function is different than a desired motion parameter based on the determination of a motion sensor. The controller configured to selectively move at least one of the first supply valve, the first return valve, the second supply valve, and the second return valve to adjust the actual motion parameter of the hydraulic function and compensate for a difference between the actual motion parameter and the desired motion parameter.

A pivot joint for a robot, including a double-acting pneumatic pivot actuator, which has a first working chamber with a first working port and a second working chamber with a second working port, and further including a valve arrangement having a first valve group for a selective connection of the first working port to one of a pressurization port and an exhaust port, and having a second valve group for a selective connection of the second working port to one of the pressurization port and the exhaust port. The valve arrangement includes a safety valve which is connected to the first working port and to the second working port and which is configured for blocking a connection between the first working port and the second working port in a blocking position and for releasing the connection between the first working port and the second working port in a release position.

A fluid system is provided that includes a first actuator, a second actuator and a valve system. The valve system includes a first control valve, a second control valve and a transfer valve. During a first mode of operation, the transfer valve is configured to fluidly couple the first control valve to the first actuator and fluidly couple the second control valve to the second actuator, and the transfer valve is also configured to fluidly decouple the first control valve from the second actuator and fluidly decouple the second control valve from the first actuator. During a second mode of operation, the transfer valve is configured to fluidly couple the first control valve to the first actuator and the second actuator, and the transfer valve is also configured to fluidly decouple the second control valve from the first actuator and the second actuator.