| 摘要 |
PROBLEM TO BE SOLVED: To prevent a decrease in output and enlarged equipment and to improve durability. SOLUTION: A leaf spring 11 is constituted by a center portion 11A to which a magnetic path member 12 is fixed, a peripheral portion 11B and a middle portion 11C between the center portion 11A and the peripheral portion 11B. In the middle portion 11C are formed a projection 11D projecting in the direction which is way from the magnetic path member 12 and a depression 11E projecting in the direction which is close to the magnetic path member 12 and the projection 11D is connected to the depression 11E to surround the center portion 11A. That is, the middle portion 11C is curved in a wavy shape in which waves spread along the center portion 11A. The surface of the leaf spring 11 side of the magnetic path member 12 is constituted by a flat portion 12A which is in contact with the reverse side of the center portion 11A of the leaf spring 11 and is fixed by a rivet 11a and a slant portion 12B which is smoothly connected to the flat portion 12A not to form an angle and is slanted to reduce the thickness of the magnetic path member 12 from the flat portion 12A to the outer periphery of the magnetic path member 12. |
