A relief valve includes: a housing; a plunger movable to each of a closed position and an open position; a differential pressure chamber; a spring member; a piston; and a damping chamber. The plunger includes a first damping passage penetrating the plunger and bringing an area outside the plunger and a through passage into communication. The piston includes a second damping passage penetrating the piston and bringing an area inside the piston and the damping chamber into communication. A communication space connected to each of the first damping passage and the second damping passage is formed between the plunger and the piston.

A check valve assembly for use with a liquid jet cutting system can include a check valve body a high-pressure fluid inlet on one end and a high-pressure fluid outlet on the other end along a central axis of the check valve body. The check valve body can have a first metallic seal surface on an outer surface of the check valve shaped to engage an endcap of the liquid jet cutting system to form a first seal. The assembly can include an annular low-pressure fluid chamber surrounding a portion of the check valve body and defined at least in part by an annular gasket, the check valve body, the first seal, and the endcap. The check valve body can include a low-pressure fluid channel, and a check valve positioned between the low-pressure fluid channel and a high-pressure fluid chamber.

A fuel valve device and a method of controlling fuel flow between a fuel tank and an engine are disclosed. A fuel valve comprises an inlet conduit including an inlet end connectable to a fuel tank and a central axis, an outlet conduit including an outlet end opposite the inlet end connectable to an engine. The outlet conduit has a central axis offset from the inlet conduit central axis. A movable valve ball is configured to block fuel flow from the inlet end to the outlet end at a predetermined pressure and to permit the fuel flow from the inlet end to the outlet end when pressure in the fuel valve device exceeds the predetermined pressure, movable along a travel axis defining an angle with the inlet conduit central axis that is greater than 5 degrees and less than 90 degrees.

A relief valve of the present invention includes a valve housing (1) including an inlet (13) into which a fluid is introduced, a valve sliding path (3) extending from the inlet (13), and a release port (15) provided in a wall surface of the valve sliding path (3), a valve piston (21) slidably housed in the valve sliding path (3) while being pressed toward an inlet side, the valve piston (21) opening and closing the release port (15), and a valve stopper (37) provided in the inlet (13) to cross an end surface of the valve piston (21) in a slender shape, receiving and stopping the pressed valve piston (21), and disposing the valve piston (21) in a position where the valve piston closes the release port (15).

A vent valve opens to provide a fluid path from a regulated pressure port to a vent port, a supply valve opens to provide a fluid path from the regulated pressure port to a supply pressure port. A control piston has a linear cam profile with a vent cam that opens the vent valve and a supply cam that opens the supply pressure valve.

A flush valve, a dust collector provided with such a flush valve and a dust collection system, are disclosed. The flush valve includes a valve body and a valve spool. The valve body is internally provided with a fluid passageway. The valve body is provided with an inlet, a first outlet and a second outlet. The first outlet is fluidly connected to a device to be flushed. The valve spool includes a movable part, a fixed part and an elastic part, the fixed part being provided in the valve body, and the elastic part elastically connecting said fixed part to the movable part. One end of the movable part being provided with a first spool land for blocking the first outlet. The first spool land being configured to be pushed away from said first outlet by fluid in the fluid passageway when the pressure drops due to blockage.

A vent valve opens to provide a fluid path from a regulated pressure port to a vent port, a supply valve opens to provide a fluid path from the regulated pressure port to a supply pressure port. A control piston has a linear cam profile with a vent cam that opens the vent valve and a supply cam that opens the supply pressure valve.

A check valve assembly for use with a liquid jet cutting system can include a check valve body a high-pressure fluid inlet on one end and a high-pressure fluid outlet on the other end along a central axis of the check valve body. The check valve body can have a first metallic seal surface on an outer surface of the check valve shaped to engage an endcap of the liquid jet cutting system to form a first seal. The assembly can include an annular low-pressure fluid chamber surrounding a portion of the check valve body and defined at least in part by an annular gasket, the check valve body, the first seal, and the endcap. The check valve body can include a low-pressure fluid channel, and a check valve positioned between the low-pressure fluid channel and a high-pressure fluid chamber.

A valve has a housing having an inlet and an outlet. A valve element is biased towards a closed position in which the valve element restricts fluid flow from the inlet to the outlet. The valve element is axially movable by fluid pressure at the inlet towards an open position in which the inlet is in fluid flow communication with the outlet. The valve further has a damping chamber having a metering orifice in fluid communication with the inlet. The damping chamber has an axially facing surface defined by the valve element and having a variable volume varying from a minimum volume when the valve element is in its closed position to a maximum volume when the valve element is in its open position.

An automatic back-pressure valve comprises a spring support (1), an ejector rod spring (2), an ejector rod (3), a piston rod (4), a guide band (5), a cylinder body (6), an O-ring seal ring A (7), an O-ring seal ring B (8), a piston rod spring (9), a cylinder cover (10), a guide sleeve (11), a conical ceramic element (12), a seal ring (13), a sealing base (14), a valve body (15), a screw (16) and a positioning sleeve (17).