GB583198A - Improvement in shuttle valve - Google Patents

Abstract

583,198. Fluid - actuated valves; hydraulic machines. ADEL PRECISION PRODUCTS CORPORATION. June 27, 1944, No. 12207. Convention date, May 22, 1943. [Classes 69 (ii) and 135] A shuttle valve comprises a housing 1 with a cylindrical bore 2 having pressure fluid inlets 5, 6 at each end and a pressure fluid outlet 7 intermediate the ends and a spring-pressed piston valve 3 slidable within the bore in response to the pressure of fluid from either inlet to close the other inlet and place the firstmentioned inlet in communication with the outlet, the piston valve carrying a packing ring 12 which is a sealing fit in the portions of the bore on opposite sides of an enlargement 13 opposite the outlet 7. The edges 14 of the enlargement 13 are bevelled to prevent injury to the packing ring as it passes over them. The piston valve 3 has a groove 11 to receive the packing ring 12 and a counterbore 15 to receive a spring 4 which normally moves the piston valve to close the inlet 6. The valve is applicable to a hydraulic system such as that shown in Fig. 8 in which a motor-operated pump 19 drawing from a reservoir 17 normally supplies fluid to the ends of a hydraulic cylinder 23 selectively under the control of a four-way valve 21 but in which a hand pump 27 drawing from the same reservoir supplies fluid to the cylinder 23 if the pump 19 fails. The outlet 7 is connected to the cylinder 23 by a pipe 24 and the inlets 5, 6 are connected to the fourway valve 21 and the pump 27 by pipes 25, 29 respectively. The hydraulic cylinder 23 is used to operate the landing gear of an aircraft.