2-62
PARKING BRAKE
Spring
Brake piston chamber
Disk
Brake piston
Cylinder block
Spline
R35Z72TM18
6)
The parking brake is a kind of negative brake which consist of disk, brake piston and spring.
The cylinder block and disk are combined with a spline, and friction material is bonded on both
sides of disk. The disk generates frictional force between the flange holder and the brake piston by
the force of spring and restricts the rotating force of the motor, achieving the best performance of
the parking brake.
When the pressurized oil flows into the motor, the plunger moves and the parking brake release
port is opened. After the oil flows into brake piston chamber, the thrust F is generated,
corresponding to the pressure receiving surface of brake piston and the thrust F becomes larger
than the force of spring F, consequently the brake piston moves toward right.
Then, the disk rotates freely between the flange holder and brake piston, and parking brake is
released.
When the motor is stopped, the plunger returns to the neutral position and the parking brake
release port is closed. Consequently the pressurized oil in brake piston chamber flows into motor
case, the parking brake acts by the force of spring.
