摘要 |
The booster has a movable wall subject to differential pressure in response to operation of a valve, to increase the effort exerted by an output member. Between the free end of the housing (1) and the free end of the valve body (4) is a flexible boot (8) having an integral seal (13) between the housing and body. The boot adjacent the seal can be depressed in order to allow inspection of the seal. Lips are formed on the seal serve to retain lubricant. |