Hyundai r35z-7 Workshop Manual page 120

SWING CIRCUIT OPERATION
DB
TO/FROM MAIN CONTROL VALVE
1) MOTOR BRAKE VALVE
Motor brake valve for the swing motor limits to cushion the starting and stopping pressure of swing
operation.
2)
MAKE UP VALVE
The make up valves prevent cavitation by supplying return oil to the vacuum side of the motor.
3) PARKING BRAKE
PARKING BRAKE "ON" OPERATION
When the safety solenoid lever is moved to upward, the oil in the parking brake is drained to the
tank. So, parking brake is applied.
PARKING BRAKE "OFF" OPERATION
The parking brake is released by the pilot pressure oil from pilot pump.
When the safety solenoid lever is moved to downward, the pilot pressure from the P4 pilot pump is
flow into parking brake through safety solenoid valve.
Then the pilot pressure lift the brake piston and release the parking brake.
SWING MOTOR
"R2"
"R1"
GA B(CCW) Mu A(CW)
PARKING BRAKE
PB
MOTOR BRAKE VALVE
MAKE UP VALVE
GB
3-17
R35Z73HC40