BREMSKRAFTVERSTÄRKER MIT EINER EINEN TASTER BILDENDEN BLOCKIERHÜLSE

摘要

A pneumatic servomotor for an assisted braking of a motor vehicle having a unidirectional clutch device (56). The clutch device (56) has a coaxial sleeve (58) that slides on a plunger (46), and a substantially ring-shaped key (60) that is arranged with a given clearance around the sleeve (58) and driven by a moving piston (22). When an input force is applied at a determined speed onto a control rod (38) that is integral with the plunger (46), the key (60) rocks and locks a finger (52) that biases the piston (22) with respect to the sleeve (58) in an axial position. The key (60) includes a peg (78) for axial indexing of the locking position of the sleeve (58).