Patent ID: 8853907

Claim:
An electric motor comprising: a first rotor configured to rotate in a first rotational plane, the first rotor comprising at least a first pair of magnets, each magnet of the first pair of magnets comprising first and second poles oriented along a respective first magnet axis perpendicular to the rotational plane, each magnet of the first pair of magnets having a length L along the first magnet axis, each magnet of the first pair of magnets having a width W in a direction perpendicular to the first magnet axis, each magnet of the first pair of magnets being separated from the other magnet of the first pair of magnets on the first rotor by a distance A; a second rotor configured to rotate in a second rotational plane parallel to the first rotational plane, the second rotor comprising at least a second pair of magnets, each magnet of the second pair of magnets comprising first and second poles oriented along a respective second magnet axis perpendicular to the second rotational plane, each magnet of the second pair of magnets having a length L along the second magnet axis, each magnet of the second pair of magnets having a width W in a direction perpendicular to the second magnet axis, each magnet of the second pair of magnets being separated from the other magnet of the second pair of magnets on the second rotor by a distance A; and a stator comprising a coil having a core with a height HC, the coil being configured in the electric motor so that the coil can exert a magnetic field on the first pair of magnets as the first pair of magnets rotate in the first rotor by the coil and, later, on the second pair of magnets as the second pair of magnets rotate in the second rotor by the coil; wherein W≦A, and L≧A.