Dual circuit braking system employing single load sensing valve in one circuit and relay valve in other circuit

摘要

A fluid-pressure operated dual circuit braking system in which each circuit serves a rear axle brake and at least one front axle brake, one circuit only including a load sensing valve. The braking pressure in the other circuit is controlled by a relay valve in response to the modulated pressure from the load sensing valve. The relay valve includes a piston which is normally balanced but moves in the event of a failure in the circuit embodying the load sensing valve, to connect the unmodulated pressure in the relay valve circuit directly to the rear axle brakes.