Center bearing of adapter plate comprising rubber and rigid plastic members developed for spring brake actuators

A spring brake actuator comprising, in order to provide sealing;

• An parking chamber (1) comprising pressurized air,
• An adapter plate (2) containing an intermediate shaft (7),
• A emergency diaphragm (3) pushed by the intermediate shaft (7),
• A flange (4) that pushes the emergency diaphragm (3),
• An emergency spring (5) that pushes the flange (4) after the pressure inside the parking chamber (1) drops,
• An intermediate shaft flange (6) that is pushed by the flange (4) connected to the intermediate shaft (7),
• The intermediate shaft (7) pushed by the intermediate shaft flange (6),
• A service chamber (8) inside which the service diaphragm (9) moves,
• A service diaphragm (9) pushed by the intermediate shaft (7)
• A shaft (10) pushed by the service diaphragm (9),
• A return spring (12) that brings back the shaft (10), characterized in that it comprises;
• A two pieced center bearing (21) comprising two types of bearings having different hardness and materials, one of which is the rubber bearing member (22) comprising an outer sealing ring (18) and an inner sealing ring (19), providing sealing, preventing the contact of the intermediate shaft (7) and the adapter plate (2);
• and the other of which is the rigid plastic bearing member (20) which strengthens the bearing of the intermediate shaft (7) in the adapter plate (2), decreases the lateral forces and prevents force losses, limits the flexibility of the intermediate shaft (7) and strengthens sealing.