| 摘要 |
PROBLEM TO BE SOLVED: To make it possible to prevent the worsening of characteristics and reliability by forming a frame and a spindle hub in one united body with a magnetic material and providing non-corrosive material for the spindle hub surface coming into contact with a disk. SOLUTION: A spindle hub and a frame (SH) in one united body 20 has a rubber 21 as non-corrosive material on a spindle hub surface on which a disc 1 is placed, and this is able to prevent a slip of the disc 1 during start and stop of a motor and also prevent rusting. At the center of SH 20, a rotating shaft 11 is attached, and a drive magnet 5 magnetized in multiple polarities is fixed in the inner peripheral portion. At the top surface of SH 20, a clamp magnet (CM) 4 for absorbing a mounting plate 2 is fixed. Generally, a gap is always set between CM 4 and a mounting plate 2, an absorbing force between the top surface of SH 20 and CM 4 becomes larger by the absorbing force between the mounting plate 2 and CM 4, and thus CM 4 will never be disengaged from SH 20. |
