Patent ID: 8324781

Claim:
A rotating electric machine comprising: a stator and a rotor that is rotatably provided through a rotary gap with respect to the stator, wherein the rotor includes a rotor core in which rotor plates punched from roll formed magnetic steel plate are laminated, and a spider that retains the rotor core; the rotor plates and the rotor core include a plurality of keys arranged in their inner circumference contacting with the spider; the spider includes a plurality of keyways arranged in its outer circumference contacting with the rotor; a plurality of keys of the rotor core and a plurality of keyways of the spider are formed in such a manner that they fit with each other; and the plurality of keys of the rotor core and the plurality of keyways of the spider fit in a combination that renders a weight imbalance of the rotor core due to lamination of the rotor plates and a weight imbalance of the spider cancel each other.