摘要 |
The invention relates to a pump unit (1) driven by an electric motor for providing vacuum for a pneumatic brake booster (2) of a motor vehicle brake system, wherein the pump unit (1) has a pump housing (3) and at least one elastic displacement element (5) for displacing a working medium, wherein the pump housing (3) is closed off by at least one working chamber cover (4) such that a working chamber (6) is delimited between the displacement element (5) and the working chamber cover (4), wherein at least one inlet valve (7) with an inlet channel (8) and at least one outlet valve (9) with an outlet channel (10) are associated with the working chamber (6), and wherein the valves (7, 9) can each be shifted automatically by means of pressure difference from a closed non-actuated starting position into an open actuating position. In order to offer a cost-effective and particularly compact pump unit, which has a reduced weight and is improved in terms of ease of production and assembly, according to the invention the inlet valve (7) and the outlet valve (9) are formed by a one-piece elastic element (11). |