A system for controlling fluid flow to and from a clutch includes a motor, a pump, and a valve assembly. The valve assembly includes a housing defining an interior. The housing defines a first orifice operably coupled to the pump and a second orifice operably coupled to the clutch. The valve assembly also includes a piston operably coupled to the motor and disposed within the interior of said housing. The piston is movable between a first position for allowing the fluid flow between the first orifice and the second orifice, a second position for obstructing the fluid flow between the first orifice and the second orifice, and a third position for limiting the fluid flow between the first orifice and the second orifice. The valve assembly additionally includes a biasing member coupled to the piston. The biasing member biases the piston toward the first position.

A flow arrangement for a pressure relief valve assembly can include a bypass flow path extending from a pressure source to a dome of a relief valve. The bypass flow path can include a valve that is configured to open and close the bypass flow path based on pressure at the pressure source or the dome, or a pressure difference between the pressure source and the dome.

A safety valve is provided with an electronic control unit for generating a control voltage. An electro-fluidic preliminary stage has a piezo bending actuator which can be actuated between a working position and a safety position by the control voltage and influences the flow of a secondary control fluid flow depending on its position. A fluid-mechanical main stage has an influencing device for influencing the flow of a primary working fluid flow. The influencing device can be actuated by means of the secondary control fluid flow which flows into a control chamber of the main stage. The control unit caries out a test of the preliminary stage repeatedly in an iterative manner after the expiration of a specified time interval. As part of the functionality test, the position of the piezo bending actuator is changed slightly by varying the control voltage.

A safety valve is provided with an electronic control unit for generating a control voltage. An electro-fluidic preliminary stage has a piezo bending actuator which can be actuated between a working position and a safety position by the control voltage and influences the flow of a secondary control fluid flow depending on its position. A fluid-mechanical main stage has an influencing device for influencing the flow of a primary working fluid flow. The influencing device can be actuated by means of the secondary control fluid flow which flows into a control chamber of the main stage. The control unit caries out a test of the preliminary stage repeatedly in an iterative manner after the expiration of a specified time interval. As part of the functionality test, the position of the piezo bending actuator is changed slightly by varying the control voltage.

A load sense pressure regulating system is provided. The load sense pressure regulating system can be operable between a flow regulation mode and a pressure limiting mode. When the load sense pressure control system is in the flow regulation mode, flow between a load sense inlet and a pilot vent are metered by a main poppet. The load sense pressure regulating system can also include a control valve downstream from the pilot vent that is configured to control a relief setting of a relief valve to regulate the load sense pressure within a desired operating range.

An irrigation management system is disclosed and positionable in-line with an irrigation pipe for monitoring and controlling a flow of fluid therethrough. In at least one embodiment, the system provides an inlet pipe and an opposing outlet pipe in serial fluid communication with the irrigation pipe. At least one fluid control valve is in serial fluid communication between the inlet pipe and outlet pipe for selectively controlling the flow of fluid therebetween. The fluid control valve provides a main valve and a hydraulic actuator for selectively moving the main valve between open and closed positions. The hydraulic actuator is also in serial fluid communication between a pair of actuator valves for moving the hydraulic actuator between open and closed positions. The system also provides at least one sample collection tank configured for temporarily storing a volume of fluid diverted from the irrigation pipe in order to be tested.

An electromagnetic and pilot-operated proportional valve with a valve slide unit (12) mounted in a valve housing (10) so as to be movable along an axial direction, which unit can be driven by an electromagnetic actuator assembly (16) provided at one axial end for the pilot-operated opening of a useful fluid inlet and/or outlet (24) of the valve housing as a response to energisation of a stationary coil (20) of the actuator assembly and interacts with mechanical force storage means (48, 50), more particularly is held in an unenergised stable axial position in the valve housing by said means, wherein the valve slide unit having a closure section (22) extending radially from one body section (30) of the valve slide unit (12) for sealing interaction with the useful fluid inlet or outlet (24) formed on a circumferential inner wall of the housing (10) interacts axially at one end, by means of the preferably cylindrical and/or coaxially extending body section (22), with a stationary guide section (40) of the valve housing to form an axial sliding bearing (62) and, at the other end, is mounted with radial play (56), wherein preferably ring-shaped sealing means (32) seal a circumferential section of the body section with radial play to the circumferential inner wall of the valve housing.

An electromagnetic and pilot-operated proportional valve with a valve slide unit (12) mounted in a valve housing (10) so as to be movable along an axial direction, which unit can be driven by an electromagnetic actuator assembly (16) provided at one axial end for the pilot-operated opening of a useful fluid inlet and/or outlet (24) of the valve housing as a response to energisation of a stationary coil (20) of the actuator assembly and interacts with mechanical force storage means (48, 50), more particularly is held in an unenergised stable axial position in the valve housing by said means, wherein the valve slide unit having a closure section (22) extending radially from one body section (30) of the valve slide unit (12) for sealing interaction with the useful fluid inlet or outlet (24) formed on a circumferential inner wall of the housing (10) interacts axially at one end, by means of the preferably cylindrical and/or coaxially extending body section (22), with a stationary guide section (40) of the valve housing to form an axial sliding bearing (62) and, at the other end, is mounted with radial play (56), wherein preferably ring-shaped sealing means (32) seal a circumferential section of the body section with radial play to the circumferential inner wall of the valve housing.

Systems, devices, and methods of modulating a pressure relief valve are provided. A modulating pilot valve assembly can receive an inlet pressure of an inlet of a pressure relief valve and can receive a dome area pressure of a dome area of the pressure relief valve. The modulating pilot valve assembly and the pressure relief valve can be configured to maintain a leak-tight seal until reaching a pilot valve pressure set point, at which the modulating pilot valve assembly instantly reduces the dome area pressure instantly, via a biasing mechanism of the modulating pilot valve assembly causing the pressure relief valve to initially open and thereafter to progressively reduce the dome area pressure in proportion to an increase in the inlet pressure and to cause the pressure relief valve to open in proportion to the increase in the inlet pressure.

Systems, devices, and methods of modulating a pressure relief valve are provided. A modulating pilot valve assembly can receive an inlet pressure of an inlet of a pressure relief valve and can receive a dome area pressure of a dome area of the pressure relief valve. The modulating pilot valve assembly and the pressure relief valve can be configured to maintain a leak-tight seal until reaching a pilot valve pressure set point, at which the modulating pilot valve assembly instantly reduces the dome area pressure instantly, via a biasing mechanism of the modulating pilot valve assembly causing the pressure relief valve to initially open and thereafter to progressively reduce the dome area pressure in proportion to an increase in the inlet pressure and to cause the pressure relief valve to open in proportion to the increase in the inlet pressure.