Patent ID: 7009322

Claim:
A rotor for a rotary electric machine, comprising: a rotor core constructed of a helically wound material sheet, wherein the material sheet is in a form of substantially belt and has a plurality of teeth extending from a first side of its middle portion and a plurality of projections projecting from a second side of the middle portion in a direction opposite to the teeth, the projections define recesses therebetween, each projection and each recess have substantially the same dimension with respect to a centerline between a first line passing through tops of the projections and a second line passing through bottoms of the recesses, and the material sheet is helically wound such that the projections are located at an inner diameter side of the rotor core, wherein a dimension (H) of the teeth and a dimension (T) of the connecting portion and the projections with respect to a direction perpendicular to the longitudinal direction of the material sheet satisfy a relation 2×H≦T.