Abstract: An anti-backflow valve for installation in a blower discharge line of a therapy tub aeration system has an air inlet, an air outlet, and an auxiliary outlet in its housing. A spring-loaded check valve member within the housing precludes fluid flow outwardly through the air inlet. Also within the housing is a combined pressure relief and float valve mechanism which opens the outlet passage in response to a pressure in the housing greater than a predetermined relief pressure or the presence of water in the housing above a predetermined level. An initial backflow of water in the discharge line closes the check valve member, the float and relief mechanism limiting the air pressure building caused by a continued backflow and permitting water to enter the housing through the air inlet when the housing is vented. After reaching the predetermined level in the housing, the entering water is discharged through the auxiliary outlet passage.

Abstract: A precise pressure regulator includes a housing defining a bore having pressure and relief zones, a pressure port communicating with the pressure zone, a relief port communicating with the relief zone, and a control port. A follower is slidable and a spool is rotatable in the bore. The spool defines a first passage for communicating the pressure zone with the control port and a second passage for communicating the control port with the relief zone. A spring biases the follower in one direction tending to block the first passage. Pressure in the pressure zone biases the follower in the opposite direction tending to block the second passage. A step motor rotates the spool in discrete steps to precisely control its position, which position determines the level at which pressure is regulated.

Abstract: A pair of spool valves C and D connected in tandem are balanced between pressures of reactant gases supplied to a fuel cell power plant G to control the pressure differences between the gases so as to maintain those pressures substantially in the proportions necessary for operation of the fuel cell.

Abstract: A valve system is disclosed in which sleeves providing an unbalanced area are arranged so that the unbalanced area is exposed to the zone of higher pressure and produces a sealing force between the sealing face of the sleeves and a mating valving surface, which force is a direct function of the difference in the pressure across the seal. Adapter rings are positioned behind each seal and a spring provides an initial light bias on the sleeve to urge it into mating engagement with the valving surface. The adapter ring and sleeve structure is arranged so that all of the sleeves, including those sleeves having an external unbalanced area, may be assembled in the valve body from the end of the sleeve receiving passage remote from the valving surface. The adapter rings also make it possible to use standard length sleeves in combination with relatively low cost adapter rings having lengths selected to provide a total sleeve adapter ring length which matches the length of the passages in the valve body.

Abstract: In order to avoid excessive wear between a sealing ring and a shaft, the sealing ring is provided with a biased sealing lip which is moved against the shaft by a pressure medium flowing into an infeed channel of the shaft. When not in use, the sealing lips are spaced from the shaft and serve to close off the pressure medium chambers of the feed device.In order to exhaust air, the flow of pressure medium is shut off to the feed device so that the sealing lips are sprung back against a projection of the device in spaced relation to the shaft. This permits the pressure medium to exhaust from the shaft through a gap between the shaft and the feed device.

Abstract: A valve which is arranged to output from a passage 12 a substantially constant-rate flow of fluid, notwithstanding changes in the flow rate entering the valve by passage 11, is arranged to provide an output from passage 12 which is variable with the static pressure in that passage. Thus when the valve is used to supply a controlled flow to a hydraulic control system an increased flow rate to the system is provided to compensate for increased leakage in the system resulting from a higher static pressure in the system.

Abstract: A control valve assembly incorporates a flow control valve, and a piston which are both biassed in the same direction against pressure in an hydraulic accumulator by first and second respective springs. Accumulator pressure in a control chamber also acts to urge the flow control valve in the same direction as it is biassed by the spring and pressure from a pump acts to bias the flow control valve in the opposite direction. A pilot dump valve controlling communication between the chamber and an outlet connection is normally biassed into a closed position by a third spring. The dump valve is adapted to open at a cut-out pressure to dump pressure from the chamber, and the cut-out pressure is determined by the area of the seating of the dump valve over which the pressure in the chamber acts, and the force in the third spring. A cut-in pressure at which the dump valve closes is determined by the area of the first piston and the force in the second spring.

Abstract: The present invention relates to a cock having a spherical plug which is supported between two annular sealing elements intended to seal the inlet channel and outlet channel thereof, of which two sealing members at least one consists of a resilient sealing member engaging said plug of said cock in an axially prestressed condition and of a coaxially located support member which limits the axial movement of said plug due to an operating pressure, which axial movement causes a deformation of the sealing member. In order to have an excellent sealing of the cock at unlimited temperature and simultaneously small operating moments the annular sealing element is shaped as a thin-walled sheet metal body which at one end is rigidly mounted to the casing of the cock and which sheet metal body comprises two coaxially arranged ring shaped sections, of which the one is shaped and arranged as deformable sealing member and the other is shaped and arranged as rigid support member mounted to said casing.

Abstract: A volume control valve in accordance with the invention is formed in a valve body which is adapted for insertion into a valve fitting. The valve body includes a valve seat insert and a valve disk. A sealing element is disposed between the valve seat insert and the valve fitting. The sealing element is carried on a supporting piece such that a first face of the sealing element is disposed on one side of the supporting piece and a second face is disposed on the other side of the supporting piece. The supporting piece is held against shoulders in the body such that the valve seat insert is prestressed by a predetermined amount by the first face. The second face is deformable against the fitting to accomodate different fitting depths.

Abstract: Electro-hydraulic control assembly for turbine valves, including electric control means, a shaft connected to a turbine valve, a valve housing and an integrated compact actuator unit disposed in the housing, the actuator unit including an electro-hydraulic converter connected to the electric control means, a hydraulic control cylinder being connected to the electro-hydraulic converter and having a control piston connected to the shaft, and a hydraulic supply system, the supply system including a fluid reservoir, a fluid pump being fed from the fluid reservoir and having a pressure side, an electric motor for driving the pump, and a hydraulic pressure accumulator connected to the pressure side of the pump.

Abstract: A vacuum check valve comprising a single umbrella valve responding to vacuum differences between the input and output of the check valve. The check valve directs the output line to feed a vacuum operated device with either the vacuum source or reference air through a bleed passage. The umbrella shaped valve eliminates the requirement for a diaphragm operated poppet valve.

Abstract: A valve for automatically charging water into a sewer line trap from a water line containing water under variable pressure comprises a case having a longitudinal bore and means for connecting the case in series flow in the water line. A hollow shaft is mounted in the case and extends from the downstream portion a predetermined distance toward the upstream portion thereof. A piston slidably mounted on the shaft divides the bore of the case into an air chamber downstream of the piston and a water chamber upstream. A floating seal is mounted within the water chamber upstream of the piston and hollow shaft. The seal is advanced and retracted with fluctuations of water pressure in the water line. In its retracted position it charges the water chamber with water and compresses the air in the air chamber. In its advanced position, it discharges the water content of the water chamber into the trap, thereby maintaining the water level thereof.

Abstract: An apparatus for maintaining valve element/valve seat alignment in valve assemblies employing trunnion mounted valve elements, the apparatus including a shaft or trunnion attached to the valve element and provided with an axially extending bore which receives an expandable plug, axially fixed relative to the shaft, there being means provided to laterally expand the plug to effect frictional engagement between the plug and the bore of the shaft.

Abstract: The apparatus comprises a circulation circuit including, in series, a cell containing the degradable solution and a pump for circulating the solution. A second, regeneration circuit is connected to the circulation circuit by valves for injecting into the latter solution having a concentration greater than that of the circulation circuit. The regeneration circuit has a surge tank or a collector vessel for collecting degraded solution from the circulation circuit.

Abstract: A plug valve and method of making same are provided wherein the valve has an outer housing and a flow passage extending through the housing and including an inlet and an outlet interconnected by a bore therebetween. A plastic sleeve is disposed within the housing and lines the bore and such sleeve has a pair of aligned ports therein which are aligned with the inlet and outlet. A rotatable plug is disposed within the sleeve and such plug has an opening therethrough which is adapted to be rotated in and out of registry with the inlet and outlet.

Abstract: A shear valve includes vent, supply and regulated ports, with the latter two including coaxial connection means.

Abstract: An improved sequencing valve of the type having a valve disk mounted within a valve housing for reciprocating and indexing movement between an inlet port and a plurality of outlet ports to couple a water supply line in sequence with a plurality of outlet conduits in response to turning on and off of a water supply. The valve disk has a flow opening therein which is closed by a spring-biased control valve when the water supply is turned on such that the valve disk is responsive to a relatively low and selected fluid pressure for movement to a position seated over the outlet ports with the flow opening in alignment with one of the outlet ports whereupon the control valve opens with increasing fluid pressure to permit water flow to the aligned outlet port.

Abstract: A valve closure member with a hub which extends beyond the radius of the circumferential sealing region of the closure member to a point greater than the extended edge of the lip of the valve seat recess in the valve body. The extended hub is spaced from the circumferential sealing region by a recess to receive a portion of the lip when the closure member is rotated.

Abstract: A butterfly valve disc with generally oval plane surface tiltingly arranged so that the outer periphery forms a perfect circle intersecting with the inner lined bore of a butterfly valve, and where the two semicircular wall portions forming said disc have annularly offset planary axes to substantially reduced hydrodynamic torque, the outer periphery further forming a rim of generally rectangular cross-section, one corner of which seatingly contacts the inner liner of said butterfly valve.

Abstract: A valve assembly is provided for a paint color change system for directing paint to spray guns from either of two supply lines selectively while connecting the other line to exhaust, and simultaneously controlling the paint pressure as a function of pilot air pressure. A valve block contains two pairs of poppet valves, each pair having a common inlet chamber connected to one of the paint supply lines and containing a pair of poppets each biased toward a seat for controlling flow to an outlet chamber, and a pilot air operated diaphragm in each outlet chamber coupled with a poppet for regulating the position of the poppet in accordance with the paint pressure in the outlet chamber and pilot air pressure.