| 摘要 |
PURPOSE:To eliminate the deformation of a plastic magnet due to a temperature change by winding the magnet consisting of magnetic powder and a synthetic resin binder on a core body made of a metal through a synthetic resin cushion material having the melting point lower than the binder and large ductility when a long-sized magnet roll is prepared. CONSTITUTION:A plastic magnet 4 is manufactured by sufficiently mixing 75- 95wt% magnetic powder and a synthetic resin binder composed of 25-5wt% polypropylene, and the magnet is wound on a shaft 2 through a cushion layer 3 consisting of polyethylene resin. In this case, polyamide resin may be used as the binder, and polypropylene resin or polyvinyl chloride resin may be employed as the cushion layer 3, and it is preferable that glass fiber is mixed previously to the cushion layer 3. The magnet is wound through extrusion molding, injection molding, etc. Accordingly, the magnet 4 is not cracked and crazed, and is fitted to long-sized molding. |
