| 摘要 |
PURPOSE:To enable to easily and safely remove the unbalance due to the discrepancy of magnetic centers by a method wherein the magnetic center of a magnetic metal ring is changed by cutting off a part of the ring. CONSTITUTION:A rotary side magnetic ring 2 having a U-like configuration in cross section is provided onto the upper end 1a of a rotator 1 rotating about the vertical axis shaftline. An electrically good conductor 5 surrounding the end 3a parts of a pair of fixed side magnetic rings 3, which are concentrically installed each other onto a stationary body 4, is provided so as to leave gaps to the ends 2a of a U-like surmount part of the rotary side magnetic ring 2. If an unbalance exists at the rotary side magnetic ring 2, the cutting off 9 of the domain containing in the circumferential angle theta of the top surface of the outer convex part of the ring 2 with the thickness delta is performed in order to remove the unbalance. |
