HYDRAULIC CONTROL VALVE OF POWERED SUPPORT UNIT Russian patent published in 2003 - IPC

FIELD: mining industry; applicable in systems of manual and pilot control of hydraulic-powered support and machines used in mineral underground mining. SUBSTANCE: hydraulic control valve includes body made with pressure and overflow chambers, user chamber and bore accommodating plug; coaxially located slide valve with packing rings and spring-loaded protective cap, bushing and sleeve whose bore accommodates piston and pusher. Sleeve bore contains pilot control piston whose bore accommodates slide valve with spring ring limiting its motion relative to piston, and supporting ring installed for shifting of piston and engagement with slide valve with its axial displacement. Slide valve has recesses for sealing members, one of which is in constant engagement with protective cap. Plug is connected with sleeve by means of threaded joint. Hydraulic control valve body has control channel for supply of pressure to under pilot control piston. Plug, protective cap, bushing, sleeve, piston, locking ring, pilot control piston, pusher, slide valve, supporting ring and spring may form monoblock installed into body and secured by lock. EFFECT: excluded pressure effect in discharge main line on operation of slide valve of hydraulic control valve and, as a result, increased speed of fulfilling of process cycle operations and extended functional potentialities due to introduction of additional piston; provision of remote control of hydraulic control valve. 2 cl, 2 dwg