SPINDLE MOTOR, METHOD OF MANUFACTURING ROTOR APPLIED TO THE SPINDLE MOTOR, AND HARD DISC DRIVE EQUIPPED WITH THE SPINDLE MOTOR

摘要

PROBLEM TO BE SOLVED: To secure a stable bearing stiffness regardless of the change of use environment, by securing a bearing stiffness of each dynamic pressure bearing, a precision in perpendicularity, etc. between a shaft and a rotor hub, and the axial dimensions of a taper seal part, and also, materializing the downsizing and thinning of the entire motor, and also to improve reliability by preventing the outflow of oil to outside of a motor, and besides, eliminating the stress transformation of the rotor hub in assembly process even if it is a small-sized and thin motor.;SOLUTION: This is a spindle motor which has a full-fill structure of fluid dynamic pressure bearing part, and herein the shaft 16 and the rotor hub 18 are molded integrally, and a taper seal part 34 is formed outward in the diametrical direction of the dynamic pressure part. Then, the shaft 16 and the rotor hub 18 are molded of a member higher in thermal expansion coefficient than a bearing retaining member 4 and a sleeve 12.;COPYRIGHT: (C)2005,JPO&NCIPI