Patent ID: 6950000
Filing Date: 2005-09-27
Classification: H01F

Abstract:
1. An electromagnetic actuator comprising: a housing defining a cavity; a solenoid coil disposed in the cavity of the housing, said solenoid coil having an axial passage extending therethrough and an outer periphery; a shaft extending through the axial passage of the solenoid coil and having a longitudinal axis; a clamp surface disposed in the cavity; an armature secured to the shaft and extending outward from the shaft to an outer peripheral surface, which is disposed outward from the axial passage of the solenoid coil, said armature being movable between a first position disposed proximate to the clamp surface and a second position disposed distal to the clamp surface, wherein when the armature is in the first position, the armature and the housing define an outwardly-extending first gap therebetween, and when the armature is in the second position, the armature and the clamp surface define a longitudinally-extending second gap therebetween, said first gap having a width in a direction normal to the longitudinal axis of the shaft and said second gap having a width in the direction of the longitudinal axis of the shaft, and wherein the width of the second gap is greater than the width of the first gap; and a permanent magnet disposed in the axial passage of the solenoid coil and operable to bias the armature toward the first position.