Apparatus and method for electronically reducing the impact of an armature in a fuel injector

摘要

A method is provided to control velocity of an armature of a fuel injector as the armature moves from a first position towards a second position. The fuel injector includes a stator core at the second position and a coil is associated with the stator core. The coil, the stator core and the armature define a magnetic circuit. The coil generates a magnetic force to cause the armature to move towards and impact the stator core. The method includes energizing the coil to permit the armature to move towards the stator core. A rate of change of magnetic flux of the magnetic circuit is determined. Closed loop feedback control of the determined rate of change of magnetic flux is used to regulate a rate of magnetic flux by controlling current to the coil so as to control a velocity of the armature upon impact with the stator core.