Trailer braking force regulator - has piston to operate regulator and relay valves connected to second piston which operates relief valve

摘要

The braking force regulator for use in the fluid pressure braking system of a trailer, comprises a relief valve, a relay valve and a braking pressure regulator valve which serves the relay valve and the relief valve at the same time. A common piston, moved by the braking pressure sensed by a pressure valve, operates the regulator valve and the relay valve and is connected to another piston which operates the relief valve. This piston is moved under the pressure of the fluid supply from a reservoir, acting against a spring and has a moderating valve which closes when the relief valve is in operation.