Komatsu Galeo PC138US-8 Shop Manual page 204

SEN02550-01
Swing holding brake
1. When solenoid valve is de-energized
Operation
As the swing holding brake solenoid valve is
q
de-energized, the pressurized oil from the self
pressure reducing valve is shut off.
Port (B) is connected to tank circuit (T).
q
Brake piston (8) is pushed down by brake
q
spring (1).
Disc (5) and plate (6) are pushed together, and
q
the brake is applied.
22
10 Structure, function and maintenance standard
2. When solenoid valve is energized
Operation
As the swing holding brake solenoid valve is
q
energized, the valve is switched.
The pressurized oil from the self pressure
q
reducing valve is conducted brake chamber (a)
via port (B).
After entering chamber (a), the pressurized oil
q
compresses brake spring (1) and pushes
brake piston (8) up.
Disc (5) is separated from plate (6), releasing
q
the brake.
PC138US, USLC-8