GB603812A - Improvements in throttling and pressure regulating valves - Google Patents

Abstract

603,812. Pressure-regulating valves. BENDIX AVIATION CORPORATION. Oct. 30, 1945, No. 28787. Convention date, Nov. 16, 1944. [Class 135] A pressure-regulating valve to control either positive or negative fluid pressure, e.g. for maintaining a constant air pressure in an aircraft fuel tank or operating a turn and bank indicator, comprises in one form for controlling positive pressure a housing 11, Fig. 3, provided at one end with a wall 12 having holes 30, Fig. 4, open to the atmosphere and a fitting 13 for connection to a source of pressure and whose other open end is closed by a collar 16 formed on a member 15 having conduits 21, 22 separated by a partition 15a which communicate with the pressure source and the instrument to be operated respectively. A valve member 26 slidable on the member 15 is formed with a piston 27 urged towards the collar 16 by a spring 31 and provided with a recess 28 which forms a communicating passage between the conduits through ports 24, 25, and a passage 23 is provided to connect the conduit 22 with the outer face of the piston. In operation, air under pressure passes through the conduit 21, ports 24, 25 and the conduit 22 and also through the passage 23 to the piston to oppose the spring pressure which, when exceeded, allows the piston to move to throttle the ports 25 and regulate the pressure to the operated instrument. In a modification for use with negative pressure, the passage 23 is dispensed with and the valve member 26 is replaced by a modified member 56, Fig. 7, which is reversed in the housing and provided with ports 62 in its periphery to establish communication between the conduits via the chamber 59. In this arrangement, the pressure source is replaced by a suction source and should the pressure operating the instrument become too low, i.e. the suction become too great, atmospheric air will enter the holes 61 to move the member 56 against the spring to adjust the amount of opening of the ports 55 in the conduit connected to the operated instrument.