Magnetic Actuator With Zero Secondary Air Gap
Original Publication Date: 1988-Nov-01
Included in the Prior Art Database: 2005-Feb-16
Many electro-magnetic actuators are comprised of a pivoted armature which bridges the space between the two pole faces of a U-shaped stator, with equal length legs, the primary pole of which carries an energizing coil. The actuating function is performed when the coil is energized and the armature is attracted toward the pole faces. The armature pivot is located on, or close to, the secondary pole face, near the side opposite the primary pole, with its axis lying in, or close to, the plane of the pole faces, centered on and perpendicular to their common centerline. With such an arrangement the magnetic path includes unequal air gaps between the armature and each pole face. It is apparent that the secondary air gap, being nearest to the armature pivot, is the lesser of the two.