| 摘要 |
PROBLEM TO BE SOLVED: To provide a hydrodynamic bearing apparatus and a spindle motor having the same.SOLUTION: There is provided a hydrodynamic bearing apparatus, including: a shaft; and a sleeve rotatably supporting the shaft, at least one of an outer circumferential surface of the shaft and an inner circumferential surface of the sleeve being provided with an upper dynamic pressure groove 260 and a lower dynamic pressure groove 270 having a herringbone-shaped pattern provided therein so as to generate fluid dynamic pressure at the time of rotation of the shaft. A width W1 of a pattern portion disposed in an upper portion of the upper dynamic pressure groove 260 is smaller than a width W2 of a pattern portion disposed in a lower portion thereof, and axial lengths L1 and L2 are identical. A width W3 of a pattern portion disposed in the upper portion is larger than a width W4 of a pattern portion disposed in the lower portion thereof, and axial lengths L3 and L4 are identical. |
