Patent ID: 8836189
Filing Date: 2014-09-16
Classification: F16C,G11B,H02K

Abstract:
1. A spindle motor comprising: a sleeve rotatably supporting a shaft and having an insertion groove provided in a top surface thereof; and a rotor case mounted on a top end of the shaft and including a protruding wall part inserted into the insertion groove, wherein a lubricant, provided to generate a dynamic pressure when the shaft rotates, forms an interface with air in a clearance formed by the protruding wall part and the insertion groove, wherein the top surface of the sleeve includes an opposite surface opposing a bottom surface of the rotor case and a spaced surface spaced apart from the bottom surface of the rotor case while being stepped from the opposite surface, and wherein the insertion groove comprises sidewalls, the sidewalls of the insertion groove being inclined such that the clearance between the protruding wall part and the insertion groove is widened towards a top portion of the insertion groove.