System Component Description

The park brake system consists of the following:

Park Brake Lever Assembly: Receives, multiplies, and transfers park brake system apply input force from driver to park brake cable system. Releases applied park brake system when park brake pedal is released and the lever is returned to the at rest position. This mechanism automatically takes up any slack in the cables and provides the correct amount of tension in the cables when the system is applied and released.

Park Brake Cables: Transfers input force received from park brake pedal, through park brake cable equalizer, to park brake apply levers.

Park Brake Cable Equalizer: Evenly distributes input force to both the left and right park brake units.

Park Brake Apply Lever: Multiplies and transfers input force to park brake actuator/adjuster.

Park Brake Actuator/Adjuster: Uses multiplied input force from apply pedal to expand drum brake pads towards the friction surface of the brake rotor. Uses multiplied input force from apply pedal to expand the drum brake shoes toward the friction surface of the brake drum. Threaded park brake adjusters are also used to control clearance between the drum brake shoes and the friction surface of the brake drum. Threaded park brake actuators are also used to control clearance between the disc brake pads and the friction surface of the brake rotor.

System Operation

Park brake apply input force is received by the park brake pedal assembly being applied. The input force is multiplied by the pedal assembly, transferred and evenly distributed, through the park brake cables and the park brake cable equalizer, to the left and right park brake apply levers. The park brake apply levers multiply and transfer the apply input force to the park brake adjusters which expand the drum brake shoes toward the friction surface of the brake drum in order to prevent the rotation of the rear tire and wheel assemblies. The park brake apply levers multiply and transfer the apply input force to the park brake actuators which apply the disc brake pads towards the friction surface of the brake rotor in order to prevent the rotation of the rear tire and wheel assemblies. The park brake pedal assembly releases an applied park brake system when it is released and returned to the at rest position.