| 摘要 |
PURPOSE:To prevent a permanent magnet from being put under radiant outward force when an axis of rotation is pressed into the retaining material for the permanent magnet, by setting a space between the permanent magnet inside and the retaining material for the permanent magnet. CONSTITUTION:The retaining material 2, 3 for a permanent magnet includes the flange portions 21, 31 in contact with the sides 11, 12 in the axial direction of a ring-formed permanent magnet 1, and the boss portions 22, 32 projected into the space inside the permanent magnet 1. The dimension of the boss portions 22, 32 in the radial direction is determined so that a space 5 can be formed between the outer surface 24, 34 of each boss portion and the inner surface 13 of the permanent magnet 1. An axis 4 of rotation is pressed into an axis slot 23, 33 formed in the middle of the boss portions 22, 32 of the retaining material 2, 3 for the permanent magnet. Because of the space 5, a radiant outward force is not applied to the permanent magnet when the axis of rotation is pressed into the retaining material for the permanent magnet. Thus, the permanent magnet is prevented from being damaged. |
