| 摘要 |
PURPOSE:To contrive preventing bending of a shaft in the case of being formed in magnetic field and making light weight by using a polymer organic material for the shaft. CONSTITUTION:On the circumference of a shaft 2 made of a polymer organic material, plural magnets with plural poles are fixed. For example, around the cylindrical cavity 51 in a metal mold 5, magnetic poles N1, S1, N2, S2 are placed and at the center of the cavity 51, a shaft 2 made of polycarbonate is placed and Ba ferrite plastic magnetic material is injected and filled in the cavity. The central axis of a plastic magnet roll obtained in this way against the circumference coincides with the central axis of the shaft 2 and the straightness in the direction of the length of the magnet is made perfect. The weight can also be made lighter than the weight of using a steel shaft. |
