Power Booster

The power booster is a single-diaphragm, vacuum-suspended unit. In normal operating mode, with service brakes in release position, a vacuum-suspended booster operates with a vacuum on both sides of its diaphragm. When brakes are applied, air at atmospheric pressure is admitted to one side of diaphragm to provide power assist. When brakes are released, atmospheric air is shut off from that side of diaphragm, air is then drawn from booster through vacuum check valve by vacuum source.