Abstract: A valve assembly includes a valve seat having a valve opening therein. A valve plate is configured to sealingly engage the valve seat in a closed position for closing the valve opening to thereby close a fluid path through the valve assembly, the valve plate being biased toward the closed position by a first spring. An actuator plate can include an inlet opening therein, the actuator plate being biased in a direction away from the valve plate by a second spring. A member includes a first end fixed to the actuator plate, an interior passage in communication with the inlet opening in the actuator plate, and a second end engageable with the valve plate when a portion of the member passes through the valve opening of the valve seat, wherein the valve plate is configured to open in response to direct fluid pressure when fluid is guided to the valve plate by the member or when fluid pressure on the actuator plate is transmitted to the valve plate via the member.

Abstract: The invention relates to a relief valve and intends to provide a relief valve which can reduce the difference between the dynamic set pressure and static set pressure of the relief pressure and its variation.An internal circumferential surface of the pilot valve element 214 to which a support 227 is inserted is expanded to form a sub valve chest 231, a support and sub valve element 232 externally fitted to the sealing member 229 is arranged in this sub valve chest 231, the clearance between the inner circumferential surface of the sub valve element 232 and the support 227 is sealed with the sealing member 229, and at the same time the sub valve element 232 is pressed against the sub valve seat 238 formed in the inner circumferential surface of the pilot valve element 214 by oil pressure exerted on the sub valve element 232 from the pressure chamber 208 side to seal the clearance between the sub valve element 232 and the support 227.

Abstract: The invention intends to provide a relief valve which can prevent malfunction caused by generation of negative pressure lowering the minimum pressure to be originally maintained by a load circuit.Maloperation of a relief valve 401 is prevented by allowing a check valve 423 for preventing a backflow from a main valve element 410 and pilot valve element 412 side to a load port side 402 to be intervened at a pressure chamber 408 between a load port 406 connected to a load circuit, a main valve element 410, and a pilot valve element 412 and by applying a hydraulic lock when negative pressure lower than the minimum pressure to be originally maintained by a load circuit is generated. And by communicating a downstream chamber 425 downstream of the check valve 423 to a return port 407 with a reset oil passage 429 which is opened and closed by a reset valve 430, the hydraulic lock is designed to be released.

Abstract: A pressurized water toy providing a pressure actuated pulsator for shooting water in consecutive pulses. The pressure actuated pulsator includes expansible inlet and outlet tubing, a reservoir for the temporary retention of water, and a sphere-shaped obturator for temporarily blocking the flow of water through the outlet tubing. Flow of pressurized water into the expansible tubing expands and elongates the tubing and forces a seal to be formed by biasing the sphere-shaped obturator against a first end of the outlet tubing compressing a spring. A buildup of pressure behind the obturator causes the expansible tubing to expand and permit passage of the pressurized water around the obturator and into and through the nozzle. When the pressure behind the obturator drops below a certain level, the obturator again blocks the orifice into the outlet tubing causing a buildup of pressure there behind and the cycling of pulse of water flow continues.

Abstract: A fluid flow control apparatus particularly useful as an automatic shut-off valve includes an arrangement which vents the interior of the valve to the atmosphere before the valve is closed by a membrane seating against a valve seat, thereby preventing the possibility of the valve stabilizing in a partially-open condition.

Abstract: A relief valve system which is made up of a valve bowl with inlet housing, a relief valve cartridge, a stop valve system, a releasable securement system, and a manual by-pass valve. The relief valve cartridge is a self-contained relief valve which is easily inserted into a reception area formed in the inlet port housing so as to be in line with the inlet port leading to a high pressure source. The stop valve system includes a spring biased poppet valve with a contact shroud that is placed in contact with the upstream end of the cartridge when the cartridge is inserted into the reception area. When the cartridge is inserted the stop valve is in a non-sealing state with respect to the inlet port. When the cartridge is removed the stop valve shifts to a sealing position. At the time a cartridge is removed for servicing a pretested cartridge is inserted in place of the removed cartridge.

Abstract: An automatic shut-off valve having a lower closing pressure than an opening pressure comprises a housing having a partition formed with a valve opening connecting the inlet to the outlet, a valve member movable in the outlet side of the partition to an open or closed position with respect to the valve opening, and a piston movable in the outlet side of the partition independently of the valve member and defining a chamber with the valve member. The piston is urged by a spring tending to close the valve member against the force of inlet pressure. The piston is formed with a passageway establishing communication between the engine chamber and the housing outlet, and has a larger cross-sectional area than the valve member, such that the valve member opens the valve opening at a predetermined inlet pressure and closes the valve opening at a lower inlet pressure.

Abstract: An impact resistant pressure operated relief valve comprising a valve body having an exhaust port and a nozzle assembly having a flow passage which terminates in an opening surrounded by an annular valve seat. A disc holder in the valve body is slidably disposed between a closed position abuting the valve seat, thus closing the nozzle passage and a second position in which the disc holder is displaced from the valve seat, thus opening the valve port to the nozzle passage. A compression spring forces the disc holder to the normally closed position. The lower portion of the disc holder is provided with a valve disc having a facing surface which is adapted to contact the valve seat in the closed position. The invention further comprises compressible shock absorber means interposed between the disc and the disc holder. The shock absorber functions to lessen the shock forces involved when the valve disc impacts upon the valve seat at closing.

Abstract: A cartridge type directional control valve assembly includes an elongated housing having a bore and a plug threaded in the outer end of the housing adjacent the bore. A changeover, spring biased piston forming a load senser or pressure sensor is provided in the bore with a sealing O ring therebetween. A coil spring is interposed between the plug and the changeover piston. The plug has a vent passage for venting the chamber of the coil spring. A valve retaining screw located in the housing, is centrally apertured and loosely receives the shank of the cone or flow control valve. A coil spring is nested within the valve retaining screw and bears against the flow control valve which is normally seated with respect to a central aperture within the cone valve insert seat. A floating ball check valve is nested within the cartridge assembly and is axially aligned with and opposite from the flow control valve. The control valve and ball check valve control flow across their respective valve seats.

Abstract: The housing of a pressure-relief valve has an inlet port forming an inlet valve seat, an outlet port, a valve chamber between the ports, and an abutment in the valve chamber. A valve body in this chamber has an inlet end engageable in the inlet valve seat and an outlet end, and is displaceable in the housing between a closed position with its inlet end seated in and blocking the inlet valve seat and an open position engaging the abutment and with its inlet end spaced from the inlet valve seat. A pilot piston in the valve chamber has a throughgoing passage opening at one end at the outlet port and forming at its opposite end an outlet valve seat engageable with the outlet end of the valve body. This piston is itself displaceable in the housing between an open position with its outlet valve seat spaced from the outlet end of the valve body in either position thereof and a closed position with its outlet valve seat engaging and blocked by the outlet end. A spring urges this piston into the closed position.