Patent ID: 8701805

Claim:
A motor having yokes concentrically arranged, comprising: a rotor having a plurality of cylindrical yokes arranged in multiple stages in a radial direction and a plurality of magnets respectively fixed to the yokes with polarities of the magnets alternated with each other in a circumferential direction of said yokes; and a stator having armature metal cores arranged to face the respective yokes and a plurality of armature coils wound on the armature cores to face the magnets; wherein the magnets are fixed to an outer and an inner circumferential surface of the yoke positioned between the armature metal cores and to an inner circumferential surface of the outermost yoke, and arranged to face each other in a radial direction, wherein the armature coils are wound on an outer and an inner side of the respective armature metal cores to face the magnets faced each other in a radial direction.