Patent ID: 7839041
Filing Date: 2010-11-23
Classification: H02K

Abstract:
1. An actuator comprising: an electromagnetically conductive housing; a rotor comprising: a first stationary pole member retained at a first axial position with respect to the rotor axis; a second stationary pole member retained at a second axial position with respect to the rotor axis; a first permanent magnet connected to the first pole member, the first permanent magnet extending essentially on a first radial side of the rotor axis, the first permanent magnet comprising a north pole segment and a south pole segment; a second permanent magnet connected to the first pole member, the second permanent magnet extending essentially on a second radial side of the rotor axis, the second permanent magnet comprising a north pole segment and a south pole segment; an electrically conductive coil situated within the housing and configured to define a cavity in which are arranged, in axial order, the second stationary pole member, the rotor flange, the first permanent magnet and the second permanent magnet; and the first stationary pole member, with a first air gap provided between the rotor flange and the first permanent magnet and a second air gap provided between the rotor flange and the second stationary pole member; wherein the rotor is held in either a first latched radial position or a second latched radial position and is switched between the first latched radial position and the second latched radial position in dependence upon direction of electrical current applied to the coil; a first stop member and a second stop member mounted at radially spaced apart locations to the second stationary pole member, the first stop member and the second stop member extending in a direction parallel to the rotor axis for selective abutment of the rotor flange; wherein in the first latched radial position the first flange segment of the rotor at least partially axially overlaps the north pole segment of the first permanent magnet and the second flange segment of the rotor at least partially axially overlaps the north pole segment of the second permanent magnet, and wherein the rotor flange abuts the first stop member; wherein in the second latched radial position the first flange segment of the rotor at least partially axially overlaps the south pole segment of the second permanent magnet and the second flange segment of the rotor at least partially axially overlaps the south pole segment of the first permanent magnet, and wherein the rotor flange abuts the second stop member.