Piston seal of the rear cover of a brake servo unit

摘要

The joint (100) has a sleeve shaped body including an inner guiding surface that receives a piston body (31) with a sealing lip at rear edge of the joint. A joint fixation groove receives inner radial edge (72) of a sleeve of a rear cover (2). The rear edge has a sleeve shaped lip (150) that emerges from the body at the base of a rear outer stop of the groove. The sleeve shaped lip is folded over the rear stop and the sleeve of the rear cover after installing the joint on the inner radial edge. An independent claim is also included for a vacuum brake booster comprising front and rear covers.