GB665800A - A hydraulic power system and sequence valve therefor - Google Patents

Abstract

665,800. Fluid-actuated valves. BENDIX AVIATION CORPORATION. Oct. 17, 1949 [Nov. 29, 1948], No. 26643/49. Class 135. A valve for automatically effecting sequential operation in one direction, and simultaneous return movement, of hydraulic jacks 1, 2 comprises a spring- loaded piston valve member 24 normally permitting flow between ports 18, 19 but preventing communication between ports 16, 18. When a control valve 5 is set as shown, pressure liquid passes from a pump 4 to a conduit 14 common to both jacks 1, 2 whose pistons commence to move downwardly and to the right respectively, exhausting liquid through conduits 15, 17. The liquid exhausting through the conduit 15 urges the valve member 24 to the right, allowing the liquid-to pass through the port 18 to a reservoir 3 but stopping the exhaust of liquid from the jack 2. Thus, the jack 1 completes its movement before the pressure in the conduit 15 falls to allow the valve member to return to normal position and permit the jack 2 to be operated. When the valve 5 is set to return the jacks, the conduit 14 is connected to a pipe 21 discharging into the reservoir and the pump delivers liquid through a check valve 6 to the jack 1 and through the ports 18, 19 to the jack 2. The valve member 24 remains in the position shown, since both ends of it are subjected to the pump pressure, the right-hand end through a passage 35.