| 摘要 |
PURPOSE: To provide a permanent magnet which can maintain a high coercive force extending for a long period. CONSTITUTION: High coercive force magnets 2 are provided at both ends of a high magnetic flux density magnet 1 positioned at the center. The amount of demagnetization by an opposite magnetic field is reduced by providing the high coercive force magnet 2 to the end large in opposite magnetic field. In the case of applying this to the magnetic pole of a permanent magnet rotating machine, the amount of demagnetization is reduced by providing a high coercive force magnet to the tip of the magnetic pole or the end in circumferential direction. |
