A hydraulic circuit for running a crawler vehicle

摘要

A hydraulic circuit for running a crawler vehicle which comprises a running frame portion provided with motors for running the crawler vehicle and an upper swivel portion turnably disposed on the running frame portion via a swivel joint. Electro-magnetic proportional flow directional control valve (a directional control valves) (15) for controlling the running motors are disposed between the swivel joint (41) and the running motors (19). The number of the high pressure passages in the swivel joint (41) can be reduced, because of increase of pressure resistance, the size of the swivel joint can be small, and accordingly, the hydraulic circuit for running a crawler vehicle can be inexpensive, and possibility for leakage of pressure oil becomes low.