Servomoteur pneumatique d'assistance au freinage à enveloppe symétrique.

摘要

A pneumatic brake servo comprising a shell (10) including a cylinder (38) and a cover (40) with an axis of symmetry (X-X'), the inside of the shell being sealingly divided by a movable wall structure (12) into a front chamber (14) permanently connected to a vacuum source, and a rear chamber (16) selectively connected to the front chamber (14) or to a pressure source via a three-way valve (26) in a rear tubular portion (22) of the movable wall structure (12) sealingly slidable in the cover (40) and actuated by a control rod (30). The cylinder (38) and the cover (40) of the servo consist of two identical shell halves (38, 40).