| abstract |
[PROBLEMS] To provide a spindle motor provided with a bearing device having a long life without causing seizure even under high-speed rotation, reducing fretting wear, and providing a high-density hard disk drive device. To be able to achieve In a spindle motor provided with an inner ring (10) and an outer ring (11) and a bearing device (4) interposed with a rolling element (13) between the inner ring and the outer ring, between a spindle shaft and a rotor, a spindle motor is provided. Inner and outer rings made of steel, The rolling elements 13 were made of ceramics. |