GB593077A - Control valve mechanism - Google Patents

Abstract

593,077. Multiple - way valves. JOHNSON, E. D. Oct. 19, 1944, No. 20261. [Class 135] A valve mechanism, particularly for controlling the How of pressure fluid to two fluidpressure-actuated devices, e.g. vehicle brakes used for steering purposes, and permitting either selective or simultaneous operation of these devices by a single control lever 55, comprises two sets of inlet and exhaust valves 31, 48 and 41, 52, operable by the lever. Conduits 7, 8, connecting with the devices communicate, through passages 22, 24 respectively, with chambers 20, 21, the supply of pressure fluid to which is controlled by the inlet valves 31, 41. When the lever 55 is in its neutral position shown, the exhaust valves 48, 52 are held open by stems 59, 58, engaging cam surfaces 64, 63 on the lever, thereby, venting the pressureactuated devices to atmosphere through ports 47, 51. For selective operation, the lever 55 is rocked about a pin 57 to open one of the inlet valves and permit the corresponding exhaust valve to close, whilst opening further the exhaust valve of the other set. For simultaneous operation, the lever 55 is rocked about, the axis of a shaft 56, mounted for rotation in the valve casing, when, owing to the inclinations of the cam surfaces 63, 64, both exhaust valves 48, 52 are closed and both inlet valves 31, 41 are opened. Pistons 35, 45, interposed, with lost-motion between the inlet valves and the lever 55, produce " feel "for the operator. A latch 65, Fig. 4, is provided, for locking the lever in the position with both inlet valves open.