Load responsive brake control valve

摘要

A load responsive valve for the braking of vehicles having load supporting air springs. The air spring pressure is employed to regulate the brake pressure through conventional proportioning-type valving. A pilot valve senses the application and release of the vehicle brakes in order to nullify operation of the air spring operated control piston so long as the brake is released, in order to reduce component wear and air consumption due to valve oscillation resulting from air spring pressure variation as the car jounces in service. This is accomplished by pilot pressure supplied via the pilot valve to counteract the air spring pressure acting on the control piston. During a brake application, the pilot valve exhausts this pilot pressure to permit the air spring pressure to operate the control valve in a normal manner.