Hydraulic Motor; Function Of Motor; Structure Of Motor And Operating Principle - Kubota U20-3 Workshop Manual

U20-3, U25-3 WSM

[2] Hydraulic motor

1) Function of motor

The hydraulic motor, which is an axial piston motor (rotating cylinder and swash plate type),
converts the hydraulic energy supplied from the pump to revolving movement.
2) Structure of motor and operating principle (See the figure below.)
The pressure oil flowing in through the hydraulic valve is supplied to the valve plate (5). When the
pressure oil is supplied to the port A, the oil flows into the cylinder port, which corresponds to the
port A, in the cylinder barrel (4) and presses the piston (6). This pressing force is converted to
turning force through the swash plate (7) and the resulting turning force is transmitted to the shaft
(3) spline-coupled with the cylinder barrel (4). The return oil in the cylinder port flows out through
the port B of the valve plate (5).
In the case of reverse rotation, the pressure oil flows in through the port B and flows out through
the port A.
Hydraulic system (Mechanism section)
IV-M-42