Servo boosters for vehicle braking systems

摘要

In order to reduce the distortion of a servo booster bousing in use the booster is provided with one or more ties which extend through the movable wall for transmitting reaction forces directly from the master cylinder housing to the vehicle bulkhead. This enables a housing of lighter weight to be employed, and an overall saving in weight to be achieved. A diaphragm support plate of the movable wall is sealed to the tie by a rolling diaphragm, and the support plate is provided with a tubular extension co-axial with the tie.