A valve device having a valve housing (10, 54, 94, 166) and fluid ports (16, 18) disposed therein, which are connected to or separated from one another in a fluid-conveying manner by means of a valve piston (22) displaceable along its longitudinal axis (24) in its various travel positions, and having at least one latching device (26, 28) for latching the valve piston (22) in at least one of its travel positions, wherein individual latching means (30, 38, 170) of said latching device, when it is actuated by an external force, take latching positions spatially different from one another, which is characterized in that, with respect to the longitudinal axis (24) of the valve piston (22), the individual latching means (30, 38, 170) of the latching device (26, 28) take positions differing from one another both in the axial and in the radial direction in the individual latching positions.

A counter pressure valve arrangement for controlling a pressure level of a hydraulic fluid in a return line from a hydraulic actuator arrangement. The counter pressure valve arrangement comprises a counter pressure valve having: a moveable valve member; a counter pressure regulating port configured for being connected to the hydraulic actuator arrangement via the return line; a tank port configured for being connected to a tank or low pressure reservoir for storing low pressure hydraulic fluid; and a pump port configured for being connected to a source of pressurised hydraulic fluid. A first position of the valve member effects fluid communication between the pump port and the counter pressure regulating port for supplying pressurised hydraulic fluid to the return line, and a second position of the valve member effects fluid communication between the counter pressure regulating port and the tank port for discharging hydraulic fluid from the return line to the tank.

An apparatus includes a hydraulic circuit that is configured to selectively open fluid communication between one portion of the hydraulic circuit and another portion of the hydraulic circuit, such as a reservoir, based on the flow of the hydraulic fluid in the one portion. When the flow of hydraulic fluid exceeds a selected threshold in the one portion of the hydraulic circuit, the flow of fluid urges the opening of a hydraulic component of the hydraulic circuit to allow fluid communication between the one portion and the reservoir to discharge fluid from the one portion.

An electro-hydraulic circuit includes a supply line that connects between a hydraulic supply device that supplies hydraulic fluid and a driving part to be driven by a hydraulic pressure of the hydraulic fluid; a switching valve disposed in the supply line to switch between switching lines for the hydraulic fluid supplied to the driving part; a pilot hydraulic line connected to the switching valve to supply the hydraulic fluid for switching between the switching lines; a check valve disposed in the pilot hydraulic line; a solenoid valve disposed in the pilot hydraulic line to change a supply state of the hydraulic fluid to the switching valve; a sealing material disposed in the switching valve to seal the hydraulic fluid; and a relief valve disposed in the pilot hydraulic line to release the pilot hydraulic pressure

An exemplary valve bank and/or modular control valve having a valve body, a valve member movable in a fluid flow of the valve body to control flow of fluid, and an onboard electronic controller that is operably mounted to the valve bank or valve body. The onboard controller is operably connected to at least one actuator of the valve, which is configured to control movement of the valve member in response to commands from the onboard controller. The onboard controller may provide diagnostics, feedback and/or control of the control valve, such as via inputs from one or more sensors that may be included in the valve. The modular control valve may be used with conventional non-intelligent valve banks to thereby impart smart diagnostics and/or feedback into the valve bank in a plug-and-play manner. A communications interface may be provided in the control valve to interface and communicate with an upper-level PLC controller.

A bistable hydraulic solenoid valve has a valve spool that transitions between two positions, remaining in one of the two positions under an attractive magnetic force when the solenoids are not energized. The valve spool has a first permanent magnet attached to one end and a second permanent magnet attached to the other end, so that the first permanent magnet faces a first solenoid, and the second permanent magnet faces a second solenoid. The first solenoid is energized to have a first polarity, and the second solenoid is energized to have an opposite polarity to concurrently push and pull the valve spool within the valve body between a first position and a second position, the first position establishing a first flow path and the second position establishing a second flow path through the valve body and valve spool so as to enable flow of hydraulic fluid.

A single solenoid-controlled electro-hydraulic liftomatic system is provided. The single solenoid-controlled electro-hydraulic liftomatic system is developed for controlling electrically, automating a hydraulic mechanism used in three-point hitch systems of tractors lifted and lowered by a mechanically controlled hydraulic mechanism. The single solenoid-controlled electro-hydraulic liftomatic system includes an actuator, a hydraulic pump, a safety element, a tank line, a valve body, a hydraulic piston, at least one solenoid valve, a piston spring, a check valve, a time-delay relay, and a button.

A flow path switching valve includes a block-shaped body having a first opening and a second opening which communicate with each other via a linear first oil path, and a third opening which communicates with the first oil path via a linear second oil path; a valve body which is provided so as to be rotatable relative to the body, and in which a communication flow path is formed that allows two openings to communicate with each other depending on the rotation position; and a locking protrusion which regulates the rotation range of the valve body in order to select the rotation position of the valve body to be a predetermined rotation position where two openings of a predetermined combination among the three openings communicate with each other via the communication flow path of the valve body.

A control valve device includes a valve main body formed to have an actuator port connected to an actuator, a communication passage formed in the valve main body and configured to allow the actuator port to communicate with a drain port, and an on/off valve provided between the communication passage and the drain port, and the on/off valve includes a sheet member assembled to the valve main body, an orifice provided in the sheet member, and a poppet member configured to open and close a sheet portion of the sheet member.

An energy saving directional-control valves (2-position and 3-position) are configured with standard manual override functionality and with the same steady-state input-output behavior as each respective standard/non-energy saving directional-control valve. This allows a standard non-energy saving valve to be replaced with an energy saving valve without reconfiguring the external electrical and manual override command logic.