A high purity valve (10) includes a valve body (12) having an inlet (40) and an outlet (42) separated by a valve seat (32), and a diaphragm (22) having a central stem (23) that has a first end coupled to a piston (20) for actuating the valve, and a poppet (28) for engaging the valve seat to close the valve. The poppet forms a dual point seal (50/52, 50′/52′) with the valve seat having at least two points of contact between an annular surface (30) of the poppet and the valve seat. The annular surface of the poppet may be either a concave surface or a convex surface that provides the dual point seal. The valve has a retainer (14) adjacent the diaphragm, and the diaphragm has a flexible web (26) that extends radially outward from the central stem. The retainer has a surface (60) adjacent the web, and the surface is spaced apart from the web such that the web does not contact the surface when the valve is pressurized.

A pulsation control device coupling a reciprocating pump with either suction or discharge piping and having a generally spherical or cylindrical interior chamber includes a curved baffle with a pressure drop device (e.g., a choke) separating the interior chamber into two volumes and forcing fluid flow through the pressure drop device. The effective fluid passage provided by the pressure drop device is smaller than the fluid passage for one or both of the inlet to and/or the outlet from the interior chamber. Fluid entering the pulsation control device reacts with fluid contained within the volume thereof on both sides of the baffle. The baffle attenuates pressure pulses within fluid passing through the interior chamber in response to operation of the reciprocating pump. The pressure drop device dampens high frequency pulsation magnitudes of pressure pulses within fluid passing through the interior chamber in response to operation of the reciprocating pump.

A vent valve apparatus (10) for use with a system for supplying breathable gas pressurised above atmospheric pressure to a human or animal. The apparatus (10) includes a gas washout vent (15), a vent valve (18) adapted to progressively restrict the flow area of the washout vent (15), and a pressure sensitive vent valve control means (20,22,23). The control means is adapted to progressively cause the vent valve (18) to restrict the flow area of the gas washout vent (15) in response to increases in the pressure of the gas supply, thereby substantially regulating the volumetric flow of gas and/or CO.sub.2 gas through the washout vent (15) over a range of gas supply pressures.

A fluid regulator includes a regulator body having a fluid inlet and a fluid outlet connected by a fluid flow path, with a portion of the regulator body forming a first chamber, an orifice disposed in the fluid flow path, a seat, and a control element disposed within the fluid flow path and shiftable between an open position spaced away from the seat and a closed position seated against the seat, with the control element arranged to respond to fluid pressure changes to control flow of a process fluid through the orifice. A diaphragm has a radially inner portion that is operatively coupled to the control element and a radially outer portion that is operatively coupled to the regulator body. The diaphragm includes a resilient redundant diaphragm sandwiched between two metal diaphragms, the diaphragm providing two separate seals.

A valve includes a cap, a diaphragm defining a movable portion, a valve housing, and a valve portion. An inlet port through which fluid flows into a valve chamber, an outlet port through which the fluid flows out from the valve chamber, and a placement portion on which a peripheral edge portion of the diaphragm is placed are provided in the valve housing. The diaphragm includes a peripheral edge portion, a center portion, a connecting portion connecting the peripheral edge portion and the center portion, and a pusher. The connecting portion has a wave shape from the peripheral edge portion side toward the center portion side such that the connecting portion first projects to a valve body portion side, and next projects to the cap side.

A fluid regulator includes a regulator body having a fluid inlet and a fluid outlet connected by a fluid flow path, with a portion of the regulator body forming a first chamber, an orifice disposed in the fluid flow path, a seat, and a control element disposed within the fluid flow path and shiftable between an open position spaced away from the seat and a closed position seated against the seat, with the control element arranged to respond to fluid pressure changes to control flow of a process fluid through the orifice. A diaphragm has a radially inner portion that is operatively coupled to the control element and a radially outer portion that is operatively coupled to the regulator body. The diaphragm includes a resilient redundant diaphragm sandwiched between two metal diaphragms, the diaphragm providing two separate seals.

A gas expansion module for use with semiconductor wafer loadlocks and other regulated-pressure components of semiconductor processing tools is provided. The gas expansion module may be barometrically isolated from the loadlock or other component and pumped down to a vacuum condition while the loadlock is performing operations at a higher pressure, such as ambient atmospheric conditions. After an initial pump-down of the loadlock is performed, the gas expansion module may be fluidly joined to the loadlock volume and the gases within each allowed to reach equilibrium. A further pump-down of the combined volume may be used to bring the loadlock pressure to a desired vacuum condition.

A tanker vehicle for distributing liquid on a surface includes a chassis that supports a tank for holding the liquid. A fluid pump discharges the liquid from the tank and is driven by a hydraulic motor. A hydraulic system delivers hydraulic fluid to the motor through a supply line and returns the fluid to a tank through a return line. A bypass circuit is disposed between the supply line and the return line, bypassing the motor. The bypass circuit includes a system for providing a combination soft start and soft stop of the hydraulic motor that is configured to enable hydraulic fluid to flow from the supply line through the bypass circuit to the return line at a start of the hydraulic system and to flow from the return line through the bypass circuit to the supply line at a shutdown of the hydraulic system.

Inside a valve housing equipped with a first flow path and a second flow path that connect in parallel with a first port and a second port, there are provided a needle valve body that opens/closes a throttle hole in the first flow path, a check valve that opens/closes the second flow path, and a piston that performs an open/close control of the needle valve body through the interaction of the pressure of a fluid introduced into a pressure chamber and the spring force of a compression spring. The needle valve body is formed at the tip of a rod coupled to the piston. Inside the rod and the needle valve body there is formed a conduction hole connecting the throttle hole and the pressure chamber.

An apparatus for allowing the repetitive oscillation of pressure in a container or vessel having a finite volume. The apparatus comprises a valve having first opening, a valve enclosure having a second opening, and a first tension device. In some embodiments the apparatus can have a chamber capable of oscillating in volume. The oscillation of the chamber volume causes a decrease in the pressure of the container. As the pressure of the space or container decreases, two openings of the apparatus become more proximate. Eventually the openings partially overlap, allowing a gas, or fluid, to enter the container, increasing pressure of the space or container. As a result of the pressure increase, the first opening and second opening become less proximate by a force of the first tension device. The apparatus can allow the container to approach substantially perfect vacuum and rise toward atmospheric pressure.