STEERING HYDRAULIC SYSTEM OF WHEELED VEHICLE Russian patent published in 1995 - IPC

FIELD: transport; steering systems. SUBSTANCE: steering hydraulic system of wheeled vehicle has main control valve unit kinematically coupled with steering wheel, power cylinder rod and steerable wheels and hydraulically coupled at one side through normally closed two-position control valve unit with second and fourth hydraulic lines of auxiliary control valve unit and power cylinder space, and at other side, with hydraulic tank and third hydraulic line of auxiliary control valve unit. First hydraulic line of auxiliary control valve unit is connected through reducing valve with pump. Safety valve is connected in parallel with pump. Hydraulic control lines are connected with normally open second two-position control valve unit and, through two restrictors, with hydraulic tank. System has two one-way pilot controlled check valves. Supply lines of the latter are connected with spaces of power cylinder through two additional holes made in power cylinder for opening when piston is in neutral position and for closing by displaced piston. Hydraulic control lines are connected with second and fourth hydraulic lines of auxiliary control valve unit. Outgoing hydraulic lines are connected with second two-position control valve unit. Two-position control valve units have common drive from torque pickup installed on steering wheel shaft and furnished with interlocking mechanism. EFFECT: enhanced efficiency of operation of steering hydraulic system. 1 dwg