| 摘要 |
PROBLEM TO BE SOLVED: To provide a technology that achieves avoidance or inhibition of an increase in magnetic resistance while avoiding or inhibiting leakage of magnetic fluxes. SOLUTION: A back yoke 124 is arranged astride between a second magnetic-pole face 122o and each end face 121 of a magnet 122. However, the back yoke 124 is in contact with each end face 121 only on the outside in the radial direction R. Each end 128 on the inside in the radial direction R of the back yoke 124 is separated in the direction of the rotation axis Q from each end face 121. Namely, the face shown to the inside in the radial direction R by the back yoke 124 has each end 128 closest to the rotation axis Q and the depth part 126c farthest from the rotation axis Q while a part between each end 128 and the depth part 126c has a level difference 125s. The back yoke 124 and the magnet 122 are fit to each other on the outside in the radial direction R from each level difference 125s. COPYRIGHT: (C)2010,JPO&INPIT |
