Electromagnetic circuit armature movement control method e.g. for IC engine positioning element

摘要

The method involves using at least one holding magnet (5,6) acting on the core (2) and at least one restoring device (3,4) also acting on the core. The start of the movement of the core after the holding current flowing in the core is switched off is detected by detecting a change in the voltage on the coil. A control signal is derived from the coil voltage change. At least one extreme value of the change in voltage caused by the core movement is detected. Where there are holding magnets for both end points, the time at which the current for the non-holding core is switched on is determined from detection of core movement at the other holding magnet.