Hydraulic Drives - Doosan DX140R Shop Manual

Hydraulic Drives

Function
1. Hydraulic Motor
This hydraulic motor is a swash plate type axial piston
motor, converting the hydraulic force from the pump to
rotary motion.
2. Brake Valve
A. Controls inertia when stopping the hydraulic motor, in
order to provide smooth stopping.
B. Prevents runaway rotation when the hydraulic motor
is rotated by external force.
This is done by preventing hydraulic cavitation.
C. Prevents the generation of abnormally high pressure
when the hydraulic motor is stopped suddenly.
3. Parking Brake
The parking brake prevents the hydraulic motor from being
rotated by external force while stopped. A friction plate
type mechanism is used, constructed so as to form one
unit with the hydraulic motor.
4. High-Low 2-Speed Switching Mechanism
Switches the hydraulic motor between high speed rotation
with low torque, and low speed rotation with high torque.
Travel Moter
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SP001346