Automatic parking brake and steering spindle

摘要

A combination automatic parking brake and steering spindle is provided for use in a self-propelled vehicle carrying an elevatable boom or work platform. The automatic parking brake includes a brake cylinder which also acts as a steering spindle for the vehicle. The parking brake is actuated by a spring carried in the brake cylinder and urges a parking brake pad into contact with a steerable wheel. The parking brake is automatically released when the hydraulic propulsion system for the vehicle is activated and hydraulic pressure enters the brake cylinder compressing the spring and releasing the parking brake.