Patent ID: 8561760

Claim:
A hydraulic system for a working vehicle comprising: a steering device; a steering lubricating circuit configured and arranged to supply oil for lubrication to the steering device; a steering case housing the steering device, and configured and arranged to store the oil used to lubricate the steering device; a low-pressure pump configured and arranged to supply the oil stored in the steering case to the steering lubricating circuit; a transmission device having a clutch; a high-pressure circuit configured and arranged to supply the oil for driving to the clutch; a high-pressure pump configured and arranged to supply the oil stored in the steering case to the high-pressure circuit; a transmission lubricating circuit configured and arranged to supply the oil for lubrication to the transmission device, the transmission lubricating circuit branching off from the high-pressure circuit via a relief valve; a transmission-lubricating assist circuit connected to the transmission lubricating circuit, the transmission-lubricating assist circuit branching off from the steering lubricating circuit; a transmission case housing the transmission device, and configured and arranged to store the oil used to lubricate the transmission device; a scavenging pump configured and arranged to return the oil stored in the transmission case to the steering device; and a torque converter being provided in the transmission lubricating circuit between the relief valve and the transmission device, the transmission-lubricating assist circuit being connected to the transmission lubricating circuit at a connection point between the torque converter and the transmission device.