PNEUMATIC SERVOMOTOR COMPRISING A DIAPHRAGM AND/OR A JOINT WHICH IS OVERMOULDED ONTO THE SKIRT

摘要

The invention relates to a pneumatic brake-assist servomotor of the type that comprises a rigid axial cover housing an essentially-truncated-cone-shaped, transverse, mobile skirt (18) which is solidly connected to a piston that is designed to actuate an associated master-cylinder (14) and which defines two pressure chambers (24, 26) in said cover. Moreover, an essentially-annular, elastomer sealing diaphragm (30) is disposed between the cover (16) and an outer peripheral zone (32) of the skirt (18). Furthermore, an essentially-annular elastomer sealing joint is inserted between an inner zone of the skirt (18) and the piston. The invention is characterised in that the sealing diaphragm (30) and/or the joint comprises one part which is overmoulded onto the skirt (18).