Vehicle brake servomotor - has diaphragm reaction support plate formed with tapering ribs including L-shaped slots to received annular insert on hub flange

摘要

The brake servo motor diaphragm (5) has a supporting reaction disc (7) on the variable pressure side. The disc is divided by hollow ribs (7) whose height decreases from a maximum of the centre to zero at the periphery. Each rib has an 'I' shaped slot, the slots receiving an annular insert (14) formed on the hub flange (10). The flange has air inlet openings (18) arranged between concentric valve seats (19, 20). A one piece plastic valve plate (21) is fitted between the power push rod (22) and the reaction member (23). The coupling is fitted between the power push rod (22) and the reaction member (23). The coupling between the flange (10) the hub part (6) and the reaction disc (7) ensures that a pulling force is made on the ribs during their conical deformation.