Abstract: In order to apply the brake to a vehicle even if one of main air-conduits for introducing brake operating air is damaged, a brake circuit system for use in the vehicle has independent right hand and left hand main air-conduits, two front and two rear brake fluid chambers placed in the main air-conduits and connected to right and left front wheel brakes and right and left rear wheel brakes, respectively, a brake operating air reservoir divided into right and left chambers connected through the right hand and left hand air-conduits to pair of right hand front and rear brake chambers and another pair of left hand front and rear brake chambers, respectively, and two front and two rear relay valves placed in the main air-conduits, respectively. A pair of right hand front and rear relay valves and other pair of left hand front and rear relay valves are actuated to be opened and closed by the operation of right hand and left hand brake valves, respectively.

Abstract: A tank assembly for a hydraulic system including a hydraulic load device and a transmission. The tank assembly comprises a tank, a weir mounted on the bottom wall of the tank, which weir functions as a partition wall for dividing the inside of the tank into a first and a second reservoirs and allows fluid to overflow from the first reservoir to the second reservoir, the first reservoir being adapted to receive fluid from both the hydraulic load device and the transmission, a dust collector mat disposed on the bottom wall of the tank for collecting dust from drained fluid, and a strainer mounted inboard on one of the side walls of the tank and extending within the second reservoir.

Abstract: A pair of pumps deliver pressurized fluid to a steering control valve assembly controlling the operation of a steering cylinder. The steering control valve assembly diverts any excess of the incoming pressurized fluid to a hoist control valve assembly controlling the operation of a pair of implement hoist cylinders. The hoist control valve assembly also diverts any excess of the incoming fluid away from the hoist cylinder pair, this time to a retarder or brake system for cooling same. The retarder receives additional cooling fluid from a hydraulic torque converter, to which the fluid has been forced from another pump. On leaving the retarder the pressurized fluid is cooled and then delivered to a transmission lubricating circuit.

Abstract: An apparatus for controlling a clutch-equipped torque converter for use in a loader vehicle having a high and a low speed clutches operatively connected with the torque converter. A regulating valve is connected with the high speed clutch for controlling hydraulic fluid pressure supplied into the high speed clutch.An accelerator for an engine and a preset lever are operatively connected with the regulating valve in such a manner that the pressure of hydraulic fluid supplied into the high speed clutch can freely be changed while the engine is in high idling region and can be kept constant while the engine is in low idling region.