| 摘要 |
PROBLEM TO BE SOLVED: To provide a motor which makes the total number of revolutions of a rotating body substantially constant for a case body, without causing destruction of the structure, while preventing the galling of a dynamic pressure gas bearing, when a motor shaft and a sleeve come into rocking contact to increase the contact friction torque of the dynamic pressure gas bearing.SOLUTION: Auxiliary bearings 171, 172 for a dynamic pressure gas bearing 130 are arranged in series therewith, a noncontact detent torque generation mechanism 180 for suppressing rotation in the auxiliary bearing is arranged in parallel therewith, the sum of the magnitude of a predetermined detent torque Td when rotation of the noncontact detent torque generation mechanism is suppressed and the magnitude of a frictional torque Tb of the auxiliary bearing is set smaller than the magnitude of the contact frictional torque of a motor shaft 120 and sleeve 130 at the time of agglutination, but larger than a viscous friction torque Ta of dynamic pressure gas bearing when it is rotating while separating the motor shaft and sleeve from each other, in a motor 100.SELECTED DRAWING: Figure 3 |
