Pneumatic servomotor comprising a diaphragm and/or a joint which is overmoulded onto the skirt

摘要

A pneumatic servomotor ( 12 ) for an assisted braking having a rigid axial casing ( 16 ) with a movable substantially truncated-cone shaped transverse skirt ( 18 ) that is integral with a piston ( 20 ) for the actuation of an associated master cylinder ( 14 ) that defines two pressure chambers ( 24, 26 ) inside the casing. A substantially annular sealing diaphragm ( 30 ) made of an elastomeric material is interposed between the casing ( 16 ) and an outer peripheral area ( 32 ) of the skirt ( 18 ) has a substantially annular seal ( 34 ) made of an elastomeric material is interposed between an inner area of the skirt ( 18 ) and the piston ( 20 ). The sealing diaphragm ( 30 ) and the seal ( 34 ) have a portion that is moulded over the skirt ( 18 ).