System Component Description

The park brake system consists of the following:

Park Brake Handle Assembly: When pulled upward applies the park brake system and engages a ratchet assembly to hold the park brake on. A button on the top of the park brake handle releases the ratchet assembly and allows the park brake handle assembly to be lowered which releases the application of the park brake system.

Park Brake Cables: Transfers input force received from park brake handle assembly through park brake cable equalizer, to park brake apply lever.

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.

Park Brake Actuator/Adjuster: Uses multiplied input force from apply lever to expand park brake shoe toward the friction surface of the drum portion of the rear brake disc. Threaded park brake actuators are also used to control clearance between the park brake shoe and the friction surface of the drum portion of the rear brake disc.

Park Brake Shoe: Applies mechanical output force from park brake actuator to friction surface of the drum portion of the rear brake disc.

System Operation

Park brake application is achieved by the park brake handle assembly being pulled upward. This also engages a ratchet assembly in the park brake handle assembly which holds the park brake on. Park brake apply input force is transferred and evenly distributed through the park brake cables and 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 actuators. The park brake actuators expand the park brake shoe toward the friction surface of the drum portion of the rear brake disc preventing the rotation of the rear tyre and wheel assemblies. The park brake handle assembly has a release button on the top of the handle which releases the ratchet assembly when depressed. This allows the park brake handle assembly to be lowered which releases the application of the park brake system.