SERVOMOTOR WITH VARIABLE ASSIST RATIO, COMPRISING A COMPACT, ELASTICALLY-DEFORMABLE MEANS

摘要

The invention relates to a pneumatic servomotor for the actuation of a brake master cylinder of a motor vehicle. The inventive servomotor comprises a mobile piston (22) and a sensor (52) which passes through said piston (22). The aforementioned piston and sensor can bias a reaction disc (32) which is solidly connected to a rod that is used to actuate an associated master cylinder. The invention is characterised in that it comprises an elastically-deformable means which is inserted axially between the sensor (52) and the reaction disc (32) and which can come into contact with the piston (22) in order to transmit an input force from the sensor (52) to the actuation rod using two assist ratios.