| 摘要 |
PURPOSE:To increase surface magnetic flux density and obtain a low inertial force by a method wherein surface multipole anisotropy having eight poles or more is given to the cylindrical part of a magnet body and the ratio between the inside and outside diameters of the cylindrical part is set to be 1-Kpi/P, and K>=1.5, where P denotes the number of magnetized poles. CONSTITUTION:A sintered cylindrical permanent magnet has a magnet-plumbite type crystal structure of MO.nFe2O3 (M denotes Ba, Sr, Pb and n denotes 5-6). In this structure, surface multipole anisotropy having eight poles or more is given to the cylindrical part of the magnet. The ratio between the inside diameter D1 and the outside diameter D2 is set to be D1/D2=1-Kpi/P and K>=1.5, where P is the number of magnetized poles. As the result, a multipole magnetized-surface magnet having high surface magnetic flux density is obtained. In addition, an optimum size of the inside and outside diameters maintaining magnetic characteristics is obtained. |
