A method for controlling velocity of an armature of an electromagnetic actuator

摘要

A method of controlling velocity of an armature of an electromagnetic actuator as the armature moves from a first position towards a second position, the electromagnetic actuator including a coil and a core at the second position, the coil generating a magnetic force to cause the armature to move towards and land at the core. A spring structure acts on the armature to bias the armature away from the second position to a resetting position, The method includes the steps of: selectively energizing the coil to permit the armature to move at a certain velocity towards the core; determining a certain voltage corresponding to a voltage across the coil when the armature is moving toward the core; and using the certain voltage as a feedback variable to control energy to the coil so as to control a velocity of the armature as the armature moves towards the core.