Vacuum system for vehicle brake servo - has servo chamber evacuated sufficient for one operation then also vacuum storage vessel to final vacuum

摘要

The arrangement is intended for producing a vacuum in vacuum system of a motor vehicle esp. for a brake servo unit. The working chamber (3) of the unit is first evacuated to a level sufficient for one operation. After a pre-determined pressure is reached, this chamber and a vacuum storage vessel (4) are simultaneously evacuated to the final system vacuum. The system may comprise a vacuum pump (2) which evacuates the chamber (3) via a non-return valve (7). A storage vessel (4) is connected to the chamber (3) via a non-return valve (6). A control valve (8) connects the vessel (4) to the pump when the pressure in the chamber (3) is sufficient for one operation.