Hydraulic Schematic for the Swing System
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| Illustration 1 | g06015782 |
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Hydraulic schematic for swing RIGHT (1) Swing motor (2) Case drain line for the swing motor (3) Return line for swing motor (4) Oil supply line for swing motor (5) Relief valve (swing RIGHT) (6) Relief valve (swing LEFT) (7) Main control valve (8) Swing control valve (9) Oil supply line (10) Hydraulic pump (11) Return line (12) Hydraulic tank (13) HPU changeover valve | |
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| Illustration 2 | g02454559 |
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Swing hydraulic system (swing RIGHT) (1) Swing motor (3) Return line for swing motor (4) Oil supply line for swing motor (5) Relief valve (swing RIGHT) (6) Relief valve (swing LEFT) (7) Main control valve | |
When the left joystick is moved to the left, the machine will swing to the left. When the left joystick is moved to the right, the machine will swing to the right. When the joystick is released from either position, the joystick will return to the NEUTRAL position.
When swing the joystick is moved to the right, a mechanical linkage shifts swing control valve (8) down. When swing control valve (8) shifts down, pump oil is directed from outer gear pump (10) through swing control valve (8) to swing motor (1). The swing motor rotates the upper structure to the right.
When swing the joystick is moved to the left, a mechanical linkage shifts swing control valve (8) up. When swing control valve (8) shifts up, pump oil is directed from hydraulic pump (10) through swing control valve (8) to swing motor (1). The swing motor rotates the upper structure to the left.
Refer to the Systems Operation, "Swing Motor" for more information on the swing motor. Refer to the Systems Operation, "Main Control Valve" for more information on the main control valve and the swing control valve.
Relief valve (5) and relief valve (6) are located in main control valve (7). These relief valves limit the pressure in the left and right swing circuits to the swing relief valve setting. The limited pressure provides a cushion effect at the start or stop of the swing operation. Relief valve (5) and relief valve (6) also aid in the braking of swing motor (1).
The swing motor is a slow running gerotor type motor. The case drain is internal in the motor. When the main pump supplies hydraulic oil to the swing motor, the motor rotates. When the motor rotates, the motor torque is transferred to the upper structure of the machine. The swing speed can be controlled through fine movements of the swing joystick.