Patent ID: 10050510

Abstract:
Cylindrical outer and inner rotors coaxially supported so as to be rotatable, and a cylindrical stator interposed between the rotors are provided, and rotational torque is transmitted between the outer rotor and the inner rotor by interaction between: a plurality of magnets uniformly arranged on the inner circumference of the outer rotor; a plurality of magnets uniformly arranged on the outer circumference of the inner rotor; and a plurality of magnetic bodies juxtaposed at equal intervals in the circumferential direction of the stator. Rod-shaped magnetic bodies extending in the axial direction of the stator are used, and each magnetic body is placed in skew arrangement with a deviation amount in the circumferential direction corresponding to 1/12 to ¼ of the juxtaposition pitch in the circumferential direction between one axial end and the other axial end. Such arrangement can effectively reduce cogging torque, and realize stable power transmission under small torque fluctuation while ensuring high torque density.