Patent ID: 6168390
Filing Date: 2001-01-02
Classification: F04B

Abstract:
A feed pump for conveying liquids in dosed amounts comprising a suction valve built into an intake line coming from an intake container; a pump chamber behind the suction valve of which the displacement volume can be changed by a pumping element; a pressure valve leading to the feed line, a venting device with a nonreturn valve arranged at the upper end of the pump; and a flow-actuated vent and bypass valve which is built into a vent line and of which the response behavior depends on the aggregate state of the fluid bearing against it, this valve being opened in the inoperative position and closed only during the compression stroke when liquid is bearing against the valve and comprising an elastic membrane, wherein the membrane is connected to a closure element which is arranged at a distance therefrom and which closes the vent line when the membrane is deflected and in that the nonreturn valve is arranged between the membrane and the closure element.