A relay valve is a key element within a vehicle's air brake system, specifically in systems utilizing air brakes, such as those commonly found in trucks. Its primary purpose is to control the application and release of air pressure to the brake chambers on the vehicle's axles. When the driver presses the brake pedal, the relay valve receives a signal from the brake pedal valve, which regulates the pressure of the compressed air sent to the relay valve. The relay valve then distributes this air pressure to the brake chambers, causing them to engage and apply braking force to the wheels. Conversely, when the brake pedal is released, the relay valve releases the air pressure, allowing the brake chambers to disengage and the brakes to release. This process ensures precise and efficient braking control, contributing to the safety and reliability of commercial trucks on the road.
