An unloading valve includes a valve body, a valve trim, a return spring, a damping hole, and an unloading groove. A combined valve includes the unloading valve and a throttling valve. The throttling valve includes a buffer stopper and a buffer chamber. A piston rod assembly of the combined valve type buffer cylinder is provided in a cylinder body. The cylinder body includes a cylinder head flange, a cylinder bottom, and a cylinder barrel. The piston rod assembly includes a guide sleeve, a piston, and a piston rod. The combined valve is provided on the cylinder. The system is located in an unloading state in a buffering process to reduce the energy loss and heat buildup of the system, prevent the pressure impact of buffering on the system, make the system more reliable, and lower the difficulty of the original buffer valve in performance matching, installation and debugging.

A gas cylinder includes supply passages for supplying, to an accommodation chamber, a part of gas supplied to a second port. When the pressure in a first pressure chamber is equal to or lower than a prescribed pressure, a valve element closes a discharge flow passage by the biasing force of a spring member and the pressure in the accommodation chamber. When the pressure in the first pressure chamber exceeds the prescribed pressure, the valve element is moved by the pressure in the first pressure chamber, against the biasing force and the pressure in the accommodation chamber, to thereby open the discharge flow passage.

A hydraulic actuator includes a piston and a cylinder. The piston is axially movable within the cylinder. A stroke end damping valve is provided in a hydraulic fluid flow passage of the actuator and adjacent an end of the cylinder. The stroke end damping valve comprises a damping orifice and a valve element for selectively varying the area of the damping orifice and thereby changing the damping provided by the orifice. The valve element projects from a wall of the cylinder into the cylinder and is engageable by the piston as the piston moves towards the end of the cylinder. This reduces the area of the damping orifice and thereby increases the damping effect on the piston towards the end of its stroke in the cylinder.

A hydraulic actuator includes a piston and a cylinder. The piston is axially movable within the cylinder. A stroke end damping valve is provided in a hydraulic fluid flow passage of the actuator and adjacent an end of the cylinder. The stroke end damping valve comprises a damping orifice and a valve element for selectively varying the area of the damping orifice and thereby changing the damping provided by the orifice. The valve element projects from a wall of the cylinder into the cylinder and is engageable by the piston as the piston moves towards the end of the cylinder. This reduces the area of the damping orifice and thereby increases the damping effect on the piston towards the end of its stroke in the cylinder.

A fluid pressure cylinder is provided with a cylinder tube having a sliding hole internally; a piston unit disposed along the sliding hole so as to be capable of moving back and forth, and a piston rod projected in the axial direction from the piston unit. The piston unit can shorten the axial dimension of a piston body by mounting a wear ring to an outer circumferential section of a ring-shaped magnet attached to an outer circumferential section of the piston body.

A reset relief valve with dampening reservoir having a piston disposed in fluid flow-blocking relationship between an inlet port and the outlet port of the body and a second position at which the piston is removed from the fluid flow-blocking position, the piston partially defines an enclosed first chamber and at least one flow passageway extending between the chamber and a reservoir chamber mounted on the body for controlled flow of hydraulic fluid to dampen the movement of the piston upon activation, The reservoir has a pressure monitor to measure fluid pressure in the system, a sight glass and index to view and measure the hydraulic fluid and a tubular flow passageway.

Examples that relate to snubbing devices to arrest or resist motion are provided. These snubbing devices are suitable for use with actuators, such as linear actuators, that desire load damping or piston speed change at the end of stroke movement of the actuator. Embodiments of the present disclosure also relate to linear actuators having a snubbing device for dampening loads, reducing piston velocity, etc., at the end of stroke movement of the actuator. In some embodiments, the snubbing device and/or other components of the actuator can benefit from additive manufacturing techniques or methodologies.

One or more components of a high pressure pump include a hydraulic surge dampener. The hydraulic surge dampener mitigates or prevents damage that results from a sudden pressure surge that results from impact of components, for example a hydraulic piston and a hydraulic head, of the high pressure pump. The hydraulic surge dampener may include one or more grooves, one or more through holes, or a combination thereof. The hydraulic surge dampener may be carried by or be part of one or more components of the high pressure pump, such as the hydraulic piston, the hydraulic head, or both.

In a cushion mechanism of a gas cylinder, when the pressure of a gas in a first pressure chamber is less than or equal to a prescribed pressure, a valve body cuts off communication between the upstream side and downstream side of a discharge flow passage by mean of the biasing force of a spring member. In addition, when the pressure of the gas exceeds the prescribed pressure, the valve body is displaced to the downstream side of the discharge flow passage against the biasing force, thereby enabling communication between the upstream side and the downstream side of the discharge flow passage.

A fluid pressure cylinder includes a cushion bearing provided movably on an outer periphery of the piston rod; a flange portion provided on the piston rod by facing the piston with the cushion bearing between them; and a collar provided movably in a radial direction on the outer periphery of the piston rod between the cushion bearing and the flange portion. End surfaces of the cushion bearing and the collar are inclined symmetrically to a center axis of the piston rod, and end surfaces of the flange portion and the collar are formed having plane shapes crossing the center axis.