GB480180A - Improvements in or relating to control valves - Google Patents

Abstract

480,180. Aircraft controls. AUTOMOTIVE PRODUCTS CO., Ltd., and CLENCH, E. C. S. Aug. 20, 1936, No. 22959. [Class 4] [Also in Group XXIX] A double-acting liquid pressure remote control system comprises three control valves or plungers which, according to the Provisional Specification may respectively control the retractable undercarriage, the flaps and the bomb door or shoot of an aircraft, each control valve 15 being movable to either of two " on " positions so as to connect one side or the other of a double-acting motor unit 47 to a unidirectional pump 45 or 46. The valves are automatically returned to a neutral position in which both sides of the motor unit are connected to a liquid reservoir 44 from which the pump draws its supply, to allow breathing and thermal compensation when the pressure on a pressure-sensitive device such as the piston 21 or 25 fed in common with the motor unit exceeds a predetermined value. As shown, three parallel slidable plungers 15, 15a, 15b operated by separate levers 31 are each connected at either end to a piston 21, 25 fed in common with the respective motor units 47, 47a, 47b. The hand levers have each a central shallow V-shaped. cam surface 35 bounded by two notches 41, 42, both notches and the surface 35 being engageable by an adjustably loaded follower or roller 36 which is displaced from one of the notches into the V-groove 35 when the pressure on the respective piston exceeds the predetermined value. The shape of the surface 35 aids the return of the lever to the central position. The motor units may have the locking. means described in Specification 434,871, [Group XXIX], which are released automatically by pressure liquid.