Dual-rotor motor

A dual-rotor motor comprising:

• a stator in which a winding is wound around a stator core;
• an inner rotor disposed at an inner-circumference side of the stator;
• and
• an outer rotor disposed at an outer-circumference side of the stator;
• wherein the inner rotor and the outer rotor are rotatably held facing the stator such that the inner rotor and the outer rotor rotate in a circumferential direction around a rotary shaft, the rotary shaft being a rotating center;
• the stator core includes a ring-like yoke, a plurality of inner teeth protruding from the yoke on the inner-circumference side, and a plurality of outer teeth protruding from the yoke on the outer-circumference side,
• the inner teeth including an inner leg extending from the yoke on the inner-circumference side and an inner head expanding in both ways in the circumferential direction from a tip of the inner leg, an opening that becomes an inner slot being formed between the adjacent inner teeth, the inner slot including an inner slot open with an inner slot open width between both circumferential ends of the inner heads of the adjacent inner teeth;
• and
• the outer teeth including an outer leg extending from the yoke on the outer-circumference side and an outer head expanding in both ways in the circumferential direction from a tip of the outer leg, an opening that becomes an outer slot being formed between the adjacent outer teeth, the outer slot including an outer slot open with an outer slot open width between both circumferential ends of the outer heads of the adjacent outer teeth;
• an inner slot angle is larger than an outer slot angle when the inner slot angle is formed by straight lines connecting the rotating center and both ends of the inner slot open, and the outer slot angle is formed by straight lines connecting the rotating center and both ends of the outer slot open;
• and
• an inner notched portion is provided on both circumferential ends of the inner head, the inner notched portion changing a space between the inner head and the inner rotor, the space being broadened as the inner notched portion comes closer to both utmost ends of the inner head, and an outer notched portion is provided on both circumferential ends of the outer head, the outer notched portion changing a space between the outer head and the outer rotor, the space being broadened as the outer notched portion comes closer to both utmost ends of the outer head.