Brake-servo with increasing output effort without increasing force on pedal

摘要

The vacuum operated brake servo has a tubular sleeve (48,54) which is displaced with the vacuum diaphragm. This sleeve partly covers the vacuum (24) and atmosphere (28) valves when the servomechanism is in its rest position, and progressively uncovers them as the servomechanism comes into operation, increasing and reducing the servo assistance progressively.