Patent 7876186 was granted and assigned to American Axle on January, 2011 by the United States Patent and Trademark Office.
An electromagnetic actuator having an annular pole piece and an annular armature with surfaces formed thereon through which a magnetic flux passes. The armature is axially movable relative to the pole piece between a first position and a second position. Magnetic flux is efficiently transmitted between the pole piece and the armature and the pole piece can be employed to guide the armature for movement thereon.