| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a ring type sintered magnet having excellent shape accuracy which can be inserted into a rotor shaft without processing an internal diameter of the ring type sintered magnet. <P>SOLUTION: The manufacturing method comprises the steps of forming a plurality of ring-shaped preliminary molded bodies to which radial alignment has been implemented, forming the ring-shaped molded body by laminating, in a plurality of stages, the ring-shaped preliminary molded bodies in the axial direction, and forming a ring type sintered magnet by sintering the ring-shaped molded bodies. The ring-shaped preliminary molded bodies are formed with the equal internal diameter and the ring-shaped preliminary molded bodies having the internal diameter which is larger than the equal internal diameter. The ring-shaped preliminary molded body having larger internal diameter is placed as the body of the lowest stage and the ring-shaped preliminary molded bodies having the equal internal diameter are stacked thereon. These molded bodies are placed on a sintering tray and sintered with the ring-shaped preliminary molded body having the larger internal diameter placed as the body of the lowest stage. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
