Pump with actively driven valves

摘要

A fluid, e.g. dry vacuum, pump comprises an inlet 891 and outlet 895 and a cylinder 802 defining an internal volume. A compression member 810 e.g. a piston or diaphragm moves within the cylinder and a valve means 841H, 835H is driven by actuators subject to a controller. The valves selectively allow fluid either to be drawn from the fluid inlet and into the cylinder or expelled by the translation of at least a portion of the compression member. The valves may be respective single inlet and outlet poppet type valves opening directly to the cylinder (Fig. 2) or may comprise an auxiliary valve 841H with either separate inlet and outlet valves (Fig. 4) or a shuttle or slide valve 835H. The valve actuators and piston or diaphragm drivers may be piezo, electromagnetic or solenoid elements. The piston may be coupled to its drive by a coupling allowing axial float.