Patent ID: 8901796

Claim:
A rotor including a rotor core, a shaft-fastening hole provided at a center of the rotor core, a plurality of slots provided in an outer circumferential portion of the rotor core, and magnets individually mounted in the slots, wherein the slots are arranged along an outer circumferential edge of the rotor core so that adjacent two slots are oriented in a reversed separated V shape or a separated V shape, each portion located in an interval between the adjacent slots forms an outer circumferential bridge located close to an outer circumference of the rotor core and an inner circumferential bridge located close to an inner circumference of the rotor core, wherein a plurality of slits each having an arc shape are formed at intervals on each of multiple concentric circles around the shaft-fastening hole and between the shaft-fastening hole and the slots of the rotor core, and the slits located on adjacent concentric circles are arranged so that the slits on one of the circles are placed to block portions located in the intervals between the slits on the other circle, wherein the portions located in the intervals between the slits formed on an outermost circle of the multiple concentric circles form a plurality of outside bridges and the portions located in the intervals between the slits formed on a circle positioned more inside than the outermost circle form a plurality of inside bridges, and the inside bridges are arranged in line, in a radial direction of the rotor core, with the outer circumferential bridges provided between the slots and the outside bridges are arranged in line, in the radial direction of the rotor core, with the inner circumferential bridges provided between the slots.