Patent ID: 6867514

Claim:
An apparatus ( 10 , 10 ′) characterized by: at least one rotor ( 12 ) having a periphery and a rotor axis ( 16 ), the at least one rotor ( 12 ) comprising a first rotor magnet ( 20 ) producing a first magnetic field, said first rotor magnet being U-shaped and having a north pole ( 23 ), a south pole ( 25 ) and a rear side ( 26 ), the rear side ( 26 ) of the first rotor magnet being adjacent to the periphery; an axle ( 80 ) to which the at least one rotor ( 12 ) is connected at the rotor axis ( 16 ) for rotation of the at least one rotor ( 12 ) about the rotor axis ( 16 ); and a stationary stator ( 48 , 51 ) comprising a generally arcuate cross-section, said stator ( 51 ) having a surface ( 64 ) opposing the periphery of the at least one rotor ( 12 ), and a longitudinal line of demarcation ( 49 ) perpendicular to the cross-section at about a midpoint of the surface, the line of demarcation ( 49 ) delineating a first side ( 52 ) of the surface from a second side ( 54 ) of the surface ( 64 ), wherein a plurality of pairs of stator magnets ( 40 , 42 ) producing a second magnetic field are attached to the surface ( 64 ), each pair of stator magnets ( 40 , 42 ) comprising a first stator magnet ( 40 ) having a north pole and a south pole and a direction of magnetization substantially parallel to the surface ( 64 ), and a second stator magnet ( 42 ) having a north pole and a south pole and a direction of magnetization substantially parallel to the surface ( 64 ), the first stator magnet ( 40 ) being on the first side of the surface ( 64 ) with the north pole of the first stator magnet being closest to the line of demarcation ( 49 ), the second stator magnet ( 42 ) being on the second side ( 52 ) of the surface with the south pole of the second stator magnet ( 42 ) being closest to the line of demarcation ( 49 ), wherein the plurality of pairs of stator magnets ( 40 , 42 ) are spaced along the line of demarcation ( 49 ) such that a first intermagnet distance measured along the line of demarcation ( 49 ) between the north pole of the first stator magnet ( 40 ) and the south pole of the second stator ( 42 ) magnet of an adjacent pair of stator magnets ( 40 , 42 ) is about equal to a second intermagnet distance measured along the line of demarcation between the south pole of the first stator magnet ( 40 ) and the north pole of the second stator magnet ( 42 ), and wherein the interaction of the first and the second magnetic fields cause the at least one rotor ( 12 ) to translate in a predetermined direction along the line of demarcation.