HYDROMECHANICAL CONTROL SYSTEM OF POWER DOZER WORKING EQUIPMENT Russian patent published in 1997 - IPC

FIELD: mechanical engineering; construction and road building machinery. SUBSTANCE: hydromechanical system has hydraulic pump, master hydraulic distributor, blade lifting hydraulic cylinder or cylinders, gearbox, unit arranged along longitudinal axis of symmetry of power dozer trunnion and consisting of tracing hydraulic distributor. Shutoff valve with spool is placed in housing of this distributor. spool is provided with grooves forming five working spaces together with housing. First and third spaces, fourth and fifth spaces are hydraulically interconnected. Shutoff valve is spring loaded relative to plug by means of thrust washer. Power dozer trunnions with joints sliding along are mechanically coupled with housing and rod of drawbar load sensor. Beams are provided with catches on free ends for connection with trunnions. working outgoing lines from tracing hydraulic distributor can be connected with rod and piston spaces of hydraulic cylinder or hydraulic cylinders thus communicating with shutoff valve. Charging valve can be made of housing, seat with valve hole, spring-loaded shutoff member and rod of drawbar load sensor. EFFECT: enhanced reliability. 3 cl, 2 dwg