A check valve assembly includes a valve, cam and arm with float rotatably connected to the valve for insertion into a fluid storage container for filling of the container without overfilling. The valve includes a channel of narrowing diameter and restricting member movably retained within the channel. One end of the restricting member rides along the cam profile as the arm rotates the cam with the changing fluid levels. When the fluid reaches maximum fill level, the restricting member contacting the cam drops into the cam valley, driving the restricting member head into engagement with the channel neck walls and automatically sealing off the valve. First and second biasing members are disposed in the channel, preferably around the stem, and collectively provide counter force sufficient to overcome the frictional forces of the seal to open valve and move the restricting member upward.

The present invention concerns a fluid stop valve unit comprising at least one fluid stop valve and a pressure responsive part, integrated or separate, arranged so that the at least one fluid stop valve is kept in a closed state. The pressure responsive part, integrated or separate, has an opening characteristic going from the closed state to an open state with a decrease of pressure after a threshold pressure has been reached.

The present invention concerns a fluid stop valve unit comprising at least one fluid stop valve and a pressure responsive part, integrated or separate, arranged so that the at least one fluid stop valve is kept in a closed state. The pressure responsive part, integrated or separate, has an opening characteristic going from the closed state to an open state with a decrease of pressure after a threshold pressure has been reached.

Actuating device for process valves (2) comprising a housing (22), comprising two housing parts (24, 26) and an actuating membrane member (20) sealingly mounted between housing parts (24, 26) and moveable in strokes which, on the one hand, forms together with the housing a pressurizeable working chamber (28) and, on the other hand, is loaded by at least one return spring (32) such that, in the unpressurized state, the actuating membrane member (20) is brought into a predefined position by means of the pre-tension of the return spring (32), wherein the actuating membrane member (20) is adapted to be connected to a valve shaft (18) connected to the valve body (16) of the process valve (2). A coupling installation (64) is provided having coupling parts (66, 68) arranged on both sides in the direction of the lifting movement of the actuating membrane member (20), which coupling parts are adapted to a connection (70) an the valve shaft (18) such that the connection of the valve shaft (18) with the actuating membrane member (20) is carried out by a one-sided mounting, wherein the valve shaft (18) is adapted to be connected to each of the coupling parts (66, 68) of the coupling installation (64). On the actuating device (2) a distance measuring system (48) is arranged, which comprises a connection (72) which is adapted to be connected to each of the coupling parts (66, 68) of the coupling installation (64) by means of a one-sided mounting, wherein the coupling parts (66, 68) are constructed in analogy to the corresponding connections (70, 72) for selectively fastening of the valve shaft (18) or the distance measuring system (48) to the coupling installation (64).

A damped check valve having multi-pressure operation is provided. The check valve includes a liner with a poppet movable within the liner. The liner defines a flow passage aligned along a longitudinal axis defined by the liner. A biasing element is operably coupled between the poppet and the liner to bias a first flow face of the poppet against an annular seat. The first flow face is configured such that a first fluid pressure is required to move the poppet from the closed position to an open position wherein the poppet is unseated from the annular seat and a second fluid pressure is required to hold the poppet in the open position, the second pressure being less than the first pressure. There is a sufficient diametrical clearance between the poppet and the liner which allows for flow control at pressures which are less than the initial opening pressure.

Pressure relief valves for use in high pressure underwater applications that may include a plunger, a body with a mating surface corresponding to the shape of a mating surface sub-section of the plunger, and one or more sealing elements, such as a pair of O-rings, are disclosed.

A check valve includes a casing in which a fluid inlet, a valve chamber, a valve seat portion, and a fluid outlet are formed; a valve body disposed in the valve chamber; and an urging unit that urges the valve body to the valve seat portion side. The valve seat portion includes a first valve seat portion disposed on the fluid inlet side of the valve chamber, and a second valve seat portion disposed on an outer periphery side of the first valve seat portion. The valve body includes a first seal portion capable of coming into close contact with the first valve seat portion, a second seal portion capable of coming into close contact with the second valve seat portion, and a first hinge portion and a second hinge portion each of which is a starting point of bending of the second seal portion. The first seal portion is formed in a disk shape using a non-elastic material, and the second seal portion is formed in a recessed frusto-conical shape in which a surface on a lower bottom side is formed of an elastic material.

A minimum pressure valve for a screw compressor for a vehicle, in particular a utility vehicle, is provided with a housing; a valve insert opening which is formed in the housing; a valve insert which is inserted into the valve insert opening and has a valve piston bore; a valve piston, a valve piston section of which is guided in the valve insert in a movable manner in the valve piston bore; at least one fluid inlet channel; and at least one fluid outlet channel. The fluid inlet channel has at least one valve seat on the inlet channel end which faces the valve piston, wherein the valve piston can be set against the valve seat in order to close the minimum pressure valve such that the fluid inlet channel and the fluid outlet channel are separated in a closed position of the valve piston. The valve seat has a valve seat diameter dA, and the valve piston section has a valve piston section diameter dB. The ratio of the valve piston section diameter dB to the valve seat diameter dA ranges between ca. 0.6 and ca. 0.95.

A pressure limiting valve (1), operationally arranged between a high pressure zone and low pressure zone (HP, LP) of a hydraulic circuit, comprises: a valve body (4) defining a passage (11) for a fluid; a closing member (8) having a stem (10) and a closing head (9) connected thereto and movably engaged with the valve body (4) so as to move along a longitudinal or axial direction (X) between positions (P1, P2) for closing and opening the passage (11), in an opening direction (OD) and closing direction (CD), respectively; a sleeve (12) which is joined to the stem (10); a spring (S1) arranged between the sleeve (12) and the valve body (4) so as to exert a force on the closing member (8) along said longitudinal or axial direction (X), in the closing direction (CD); said sleeve (12) is irreversibly locked to the stem (10) by means of a threadless mechanical connection, in a predefined longitudinal or axial position of the said stem (10), so that the spring (S1) exerts a force of predefined value on the closing member (8) arranged in the closed position (P).

A new type of pressure relief valve is described herein which has advantages over standard valves in that it may comprise a longer plunger than normal, and two guiding points located far away from each other for guiding the plunger within the housing. The valve may also comprise improved exhaust ports and an anti-rotation washer.