Brake Caliper Function
Parking brake activated
When the parking brake is activated the electric motor produces a torque that is converted into compressive force via a spindle. The spindle is fitted in the brake piston and presses on it so that the brake pads are applied. When the current to the electric motor is disconnected (vehicle parked) the self-locking thread on the shaft maintains the brake pressure.
The shoes are held in position in the drum brakes via a securing spring, which is fixed in the protective plate.
Parking brake released
When the parking brake is released the spindle is threaded back and the piston's pressure releases. The shaft stops in its position.
The spindle follows the wear on the brake pads
The spindle on the shaft is threaded out constantly with the piston in order to follow the wear on the brake pads. The spindle applies its pressure in the same way the whole time.