SPINDLE MOTOR AND DRIVING DEVICE OF RECORDING DISK HAVING THE SAME

摘要

Provided are a spindle motor which can improve a rotating characteristic and a driving device of a recording disk having the same. The spindle motor comprises: a base member having an installation unit; a lower thrust member which is inserted into and installed on the installation unit; a shaft of which a lower part is installed and fixed on the lower thrust member and which has a flange unit; a rotating member which is installed on the shaft to be rotated around the shaft; and a cap member which is installed on the rotating member and placed on an upper part of the flange unit. On at least one among the lower part of the shaft and a facing surface of the rotating member which is placed to face the lower part of the shaft, a lower radial dynamic pressure groove is formed. An upper radial dynamic pressure groove is formed on at least one among the circumferential surface of the flange unit of the shaft and a facing surface of the rotating unit which is placed to face the circumferential surface of the flange unit.