| 摘要 |
<p>For molding a plastic magnet by injecting a resin material mixed with a compounded magnetic powder into a molding cavity (3) wherein a magnetic field is produced by a magnetizing yoke (4), a strong magnetic field is produced in the molding cavity (3) by a narrow-width projection (5) of the magnetizing yoke (4), and a relatively weak magnetic field is produced by a recessed part (7) in a predetermined region on one side of this strong magnetic field region. Thus, a required circumferential magnetic force pattern for the plastic magnet is realized in a short time without needing many know-hows. Especially, when manufacturing a magnet roller by combining magnet pieces, the magnetic force produced at an axial end of the magnet roller is almost equal to that at the center part. Thus, a method for manufacturing a magnet roller which dispenses with the adjustment of a magnetic force by grinding a formed magnet roller.</p> |
