Vehicle brake pressure limiter - has differential area plunger exerting max force to wheel cylinders upon circuit failure

摘要

The brake power controller is basically an axially movable differential piston whose smaller surface is connected to the master cylinder, and the larger surface supplying pressure to the wheel cylinders. On a dual circuit brake system the failure of one circuit should enable the system to convey the entire brake power to those wheels connected to the intact circuit. On previous systems the arrangement of the pressure limited did not make it possible to comply with this. In the case of the circuit running through the pressure limiter, the pressure would reach the brake cylinders, but if the circuit running through the differential piston fails the position of the pressure limited would not permit the pressure to reach the brake cylinders connected to that end of the piston. The present arrangement prevents the pressure limiter becoming effective in the case of failure.