What is the function of a quick release valve in air brake systems?

The function of a quick release valve in air brake systems is to allow brake actuation air to be quickly exhausted near the brakes it serves. This is crucial for improving the response time of the braking system. When the brake pedal is pressed, the quick release valve rapidly releases air from the brake chambers when the brakes are disengaged, allowing for quicker release of the brakes. This results in faster return to the position when the brakes are not applied, minimizing the delay in re-engaging the brakes when needed.

This ability to vent air quickly enhances the efficiency and responsiveness of the braking system, enabling a more effective performance during operation, especially in tight or high-frequency stopping situations that are typically encountered in bus driving scenarios.