Patent ID: 7908737

Claim:
A production method of a fluid dynamic-pressure bearing used in a spindle motor comprising a stationary section including a sleeve having a bearing hole, and a rotor section including a shaft inserted into the bearing hole and an annular portion extending radially outwards from an outer circumferential face of the shaft, the rotor section rotating about a center axis, comprising: a lifting step for relatively lifting the rotor section with respect to the sleeve in a direction along the center axis by supplying a gas to a lower opening portion of the bearing hole, and by causing an gas flow to occur in an outward direction of the annular portion via a radial gap between the outer circumferential face of the shaft and an inner circumferential face of the sleeve and an upper opening portion of the bearing hole; a measuring step for measuring run-out synchronized with the rotation of the rotor section with respect to the rotor section or the stationary portion while the lifted condition is maintained; and an adjusting step for adjusting the run-out synchronized with the rotation of the rotor section based on the measured result obtained in the measuring step.