| 摘要 |
PROBLEM TO BE SOLVED: To provide a compact hydrodynamic bearing device of large load capacity, to miniaturize a spindle motor, and to increase speed of the rotation and accuracy of the rotation of the spindle motor using the hydrodynamic bearing device, in particular, an air dynamic bearing device. SOLUTION: This spindle motor 10 is provided with the hydrodynamic bearing device composed of a shaft 26 having a flange part 26a, a sleeve (bearing member) 34 sliding along an outer peripheral face of the shaft 26 and a lower face of the flange part 26a, and an upper thrust 36 (bearing member) sliding along an upper face of the flange part 26a. The outer peripheral face of the shaft 26, and the upper face and a lower face (first sliding face) of the flange part 26a are respectively provided with first hydrodynamic generating grooves 50, 54, 58. An inner peripheral face and an upper end face of the sleeve 34, and a lower face (second sliding face) of the upper thrust 36 are respectively provided with second hydrodynamic generating grooves 52, 56, 60.
|
