HYDRAULIC SYSTEM OF VEHICLE HYDROMECHANICAL TRANSMISSION Russian patent published in 2002 - IPC

FIELD: transport engineering. SUBSTANCE: hydraulic system of vehicle hydromechanical transmission has torque converter circuit including torque converter, first pump, first heat exchanger coupled hydraulically through hoses, planetary gearbox circuit including planetary gearbox, second and third pumps, filter, pressure control mechanism, second heat exchanger, gearshift mechanism, automatic control mechanism, damper, speed and power pickups hydraulically connected through hoses and channels and operated through electric coupling circuit by means of mode selector, working liquid cooling circuit including radiator, and circulating pump. System is furnished additionally with comparator made in form of hydraulic cylinder with single-acting rod and balancing spring, tank, fourth pump, distributor, pressure limit valve, safety valve, first and second two-position valves, first, second, third and fourth three-position valves and pneumomechanical change-over switch being pneumatically intercoupled. Inlets of comparator are hydraulically coupled with outlets of second and fourth three-position valves and are mechanically coupled with pneumomechanical change-over switch and distributor. Inlets of distributor are hydraulically coupled with outlets of first and third three-position valves, and fourth pump coupled hydraulically with safety valve and tank. Outlets of tank are hydraulically coupled with torque converter circuit through pressure limit valve and inlet of pressure control mechanism. EFFECT: increased service life and operation reliability of hydraulic system, reduced time required for revealing and eliminating troubles, provision of compact and reliable design. 1 dwg