OIL PRESSURE CIRCUIT FOR WORKING VEHICLE

PURPOSE: To operate a hydraulic actuator also when failures are generated, by providing a main oil pressure pump to be usually used as an oil pressure pump, and an emergency oil pressure pump to be used in emergency, and connecting the emergency oil pressure pump to subpipe lines branched from the main pipe line. CONSTITUTION: In a working vehicle, when an engine E fails and is stopped, or when operating oil is not discharged from a main pump 21, both stop valves 24 are closed, and emergency hose lines 33a, 33b are connected to sub lines 25, 32. An emergency pump 31 is driven by operating an electric motor M, and a selector valve 34 is switched to the left position. Therefore, operating oil is allowed to flow into a rod side oil chamber 16b of a elevating cylinder 16 through the line parts 32d, 33b and the second sub line 25b. Moreover, operating oil in a bottom side oil chamber 16a is allowed to flow into an oil tank 26 through line parts 33a, 32b, as a result, the elevating cylinder is contracted.