Brake booster

摘要

A brake booster can switch operating mode from a positive-pressure mode using a signal-controlled fluid pressure supplier to a vacuum-pressure mode and vice versa. The booster includes a booster converter holding both an air valve and a vacuum valve of the booster closed in the positive-pressure mode or holding the booster air valve in its closed and open positions while holding the booster vacuum valve in its open and closed positions respectively when the brake pedal is released and depressed in the vacuum mode. The fluid pressure supplier is enabled while both booster valves are in the closed position in the positive-pressure mode.