Patent ID: 6205110
Filing Date: 2001-03-20
Classification: F16F,G11B

Abstract:
A disk drive motor comprising:a shaft;a disk-shaped rotor fixed on one end of the shaft and having an annular projection surrounding the shaft, the rotor having an annular groove on the bottom of the annular projection;a base plate having a sleeve member;a bearing means located in the sleeve member and interposed between the shaft and the sleeve member for rotatably supporting the shaft;a yoke including a plate portion having a central opening and a circular depending portion depending from radially outward portion of the plate portion, the yoke being fixed to the annular projection of the rotor at the inner edge of the central opening so as to be in contact with the upper surface of the plate member and the lower surface of the rotor to close the opening of the annular groove and form a closed annular space;a rotor magnet secured on the inner peripheral surface of the circular depending portion of the yoke;a stator disposed on the base plate so as to oppose the rotor magnet; anda balancing member movably located in the annular space.