Oil supply system for working vehicles

Abstract

In a working vehicle in which a lower portion of the interior of the vehicle body is employed as an oil sump (49) for reserving oil supplied to oil-operated clutches (43F, 43R) by pump (48), an oil reservoir chamber (91) having an overflow opening (91a) is provided. The overflow opening is arranged such that the oil level (OLb) in the reservoir chamber is kept higher than the oil level (OL) in the sump due to overflow of oil from the chamber into the sump through the opening. Oil drain ports (68T.sub.1, 68T.sub.2) of a control valve (68) for controlling the operation of the clutches are communicated into the reservoir chamber at a level lower than the oil level in the chamber. The intrusion of air into the valve and fluid passages connected thereto through the drain ports is prevented. Preferably, valve casing for the valve is fixedly supported by a housing (1) forming a part of the vehicle body and the reservoir chamber is defined between two casing members (56, 57) such that the overflow opening opens directly at the interior of the housing. (FIG. 5)

Dependencies are inferred from the claim text.