GB613006A - Improvements in or relating to electro-hydraulic control systems - Google Patents

Abstract

613,006. Valves; fluid-pressure servomotorcontrol systems. SPERRY GYROSCOPE CO., Inc. July 7, 1943, No. 11071. Convention date, July 8, 1942. [Class 135] In a servomotor control unit of the kind in which control valves 36, 37, Fig. 4, are pivotally connected to a rocker 33, Fig. 1, the rocker constitutes or is secured, e.g. by a shaft 27, to the three-legged armature 25 of a differential electromagnetic controller, the outer legs being provided with windings 31, 32. The valves may have rigid or flexible stems and are employed in a hydraulic control system of the kind described in Specification 538,526, comprising a double-acting, threegear pump 52, 53, 54, and a servomotor 58 connected by rack and pinion gear to a pulley 62 carrying a cable 63 for operating the object to be controlled. The pump withdraws liquid from the sump through the pipes 50, 50<1>, Fig. 1, and discharges it through pipes 55, 55<1> to the ends of the servomotor, the operation of which is determined by the current supplied to the windings 31, 32. Thus, assuming the windings to be activated to move the armature 25, and therefore the rocker 33, in a clockwise direction, this will result in the closing of the valve 37 on its seat 45 and the opening of the valve 36, thus increasing the pressure on the right side of the servomotor piston and moving it to the left, the displaced liquid passing through the pipe 59 to the opening 56 in the base of the sump and thence past the valve 36 and through the ports 47 in the valve housing 46 into the sump. A combined pump and valve housing may be built up of plates 68 ... 71, Fig. 10, the outer pump gears rotating on hollow shafts which house the valves 36, 37. Specification 612,897, [Group XXXVIII], also is referred to.