A articulate vehicle comprises a first frame disposed at one of front and rear portions of the vehicle and a second frame disposed at the other of front and rear portions of the vehicle. The first frame supports a first transaxle apparatus supporting a first axle. The second frame supports a second transaxle apparatus supporting a second axle. Proximal ends of the frames with respect to the vehicle are coupled to each other through a coupling part so that the first and second frames are rotatable relative to each other around a vertical axis according to steering operation. An engine is mounted on the first frame. A first hydraulic motor is integrally assembled in the first transaxle apparatus so as to drive the first axle. A working vehicle is equipped at a distal side of the second frame with respect to the vehicle. A second hydraulic motor is integrally assembled in the second transaxle apparatus so as to drive the second axle. A hydraulic pump is mounted on either the first or second frame, drivingly connected to the engine, and fluidly connected to both the first and second hydraulic motors.
A hydrostatic transaxle is provided for a vehicle having a first axle and a second axle. The hydrostatic transaxle comprises: a hydraulic pump; a first hydraulic motor drivingly connected to the first axle; a closed circuit fluidly connecting the hydraulic pump to the first hydraulic motor; and a fluid-supply switching device shifted between a supply position for supplying fluid from the closed fluid circuit to a second hydraulic motor, which is disposed on the outside of the hydraulic transaxle and is drivingly connected to the second axle, and a supply-stop position for stopping the supply of fluid from the closed fluid circuit to the second hydraulic motor. The first hydraulic motor is variable in displacement, and the hydrostatic transaxle further comprises a linkage system for associating the switching of the fluid-supply switching device between the supply position and the supply-stop position with an operation for changing the displacement of the first hydraulic motor.
A hydraulic four-wheel driving articulated vehicle comprises: a first frame, on which first axles and a first hydraulic motor driving the first axles are mounted; a second frame, on which second axles and a second hydraulic motor driving the second axles are mounted, wherein the first and second frames are connected to each other so as to be relatively rotatable centering on a vertical axis by a steering operation; a hydraulic pump; a hydraulic circuit fluidly connecting the first and second hydraulic motors in series to the hydraulic pump, wherein the hydraulic circuit includes a passage interposed between the first and second hydraulic motors; and pressure control means for releasing oil from the passage between the first and second hydraulic motors when the first and second frames are relatively rotated by the steering operation of the stationary vehicle and backpressure oil discharged from the first and second hydraulic motors is excessively accumulated in the passage between the first and second hydraulic motors.
