SPINDLE MOTOR AND HARD DISK DRIVE INCLUDING THE SAME

摘要

There are provided a spindle motor including a second thrust member installed on a base member; a shaft installed on the second thrust member; a sleeve disposed above the second thrust member and installed to be rotatable with respect to the shaft; a rotor hub coupled to the sleeve; and a first thrust member disposed above the sleeve and installed on the shaft, wherein the sleeve includes a circulation hole penetrating therethrough in an axial direction, the sleeve and the first thrust member include a first thrust bearing formed therebetween and the sleeve and the second thrust member include a second thrust bearing formed therebetween, and an area by which an upper end portion of the circulation hole is overlapped with the first thrust bearing is larger than an area by which a lower end portion of the circulation hole is overlapped with the second thrust bearing.

主权项

1. A spindle motor comprising:
a second thrust member fixedly installed on a base member; a shaft fixedly installed on the second thrust member; a sleeve disposed above the second thrust member and installed to be rotatable with respect to the shaft; a rotor hub coupled to the sleeve to thereby be rotated together with the sleeve; and a first thrust member disposed above the sleeve and fixedly installed on the shaft, wherein the sleeve includes a circulation hole penetrating therethrough in an axial direction, the sleeve and the first thrust member include a first thrust bearing formed therebetween and the sleeve and the second thrust member include a second thrust bearing formed therebetween, and an area by which an upper end portion of the circulation hole in the axial direction is overlapped with the first thrust bearing is larger than an area by which a lower end portion of the circulation hole in the axial direction is overlapped with the second thrust bearing.