Rotary actuator

Claim 1

A rotary actuator comprising: first and second stator sections, each of said stator sections including magnetic material; means for mounting said stator sections with said stator sections being separated by a relatively high reluctance region; a rotor including a permanent magnet having first and second poles of opposite polarity; means for mounting said rotor for rotation about an axis with the rotor being adjacent said stator sections, said rotor being rotatable from a first position through a predetermined number of degrees about said axis to a second position; said stator sections extending for a substantial distance around the rotor in a direction circumferentially of the axis of rotation; first electrical means for magnetizing said stator sections to move said rotor from said first position to said second position, at least one zone of said first stator section attracting said permanent magnet toward said second position and at least one zone of said second stator section repelling said permanent magnet from said first position toward said second position; said rotor including a segment constructed of magnetic material which is not permanently magnetized and located adjacent the periphery of the rotor; and said segment being a first peripheral surface segment, said rotor having a second peripheral surface segment intersecting said first peripheral surface segment at a zone of intersection, said surface segments being of different configurations, said magnet having an axis of magnetization extending generally toward the zone of intersection.