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PARKING BRAKE
The parking brake is of wet type multi-plate construction of hydraulic release type and has a shaft
lock mechanism that changes between ON and OFF of the brake by external signal pressures.
Parking brake ON
When the hydraulic pressure for brake release is shut, the disc coupled to the periphery of the
cylinder block via the spline is pushed by the spring force against the brake piston (pinned to the
case so that it will not rotate) and the cylinder block and the case secured by the frictional force.
Thus the shaft is locked.
Parking brake OFF
When the brake release pressure is introduced to the brake cylinder chamber (C) via the "PB"
port, the brake piston is operated by the release pressure in opposition to the spring force to
eliminate the force of friction with the disc, thus allowing the shaft to rotate freely.
2)
Η
Η
Θ
Cylinder block
Brake piston
Disc plate
"PB" (Brake releasing pressure) OFF
Brake cylinder chamber "C"
"PB" (Brake releasing pressure) ON
R35Z72SM03
R35Z72SM04
