| 摘要 |
A magnetic drive metering pump in which a movable thrust member is fixed to a diaphragm and is axially movable in a magnet shroud. The thrust member, on electrically actuating the magnet shroud, is drawn into the magnet shroud against the force of a recuperating spring, and after deactivating the magnet shroud, is returned to a starting position. The diaphragm cooperates alternately with an outlet and an inlet valve to produce a pump stroke in a pump metering head. The magnetic drive metering pump has a reference element associated with the thrust member and diaphragm, the position of which reference element is detected by a positional sensor. The positional sensor provides a signal which has a fixed relationship to the position of the reference element, and the motion of the thrust member is controlled by a control circuit such that it follows a predetermined nominal profile. |
