Patent ID: 7733599
Filing Date: 2010-06-08
Classification: G11B

Abstract:
1. A magnetic disk unit having: a magnetic disk; a head drive mechanism in which there has been mounted a head accessing the magnetic disk; a base accommodating the magnetic disk and the head drive mechanism, and possessing a flat part, in which a threaded hole is formed, in a circumference of an opening edge; and a top cover which is formed by a material whose thermal expansion coefficient differs from a thermal expansion coefficient of a material of the base, in which there is provided an escape hole, for a screw, position-aligned to the threaded hole of the flat part, and which is attached to the base by the screw penetrating through the threaded hole and the escape hole for the screw, wherein a slip mechanism reducing a slip friction resistance is provided in a first contact portion between the flat part and the top cover, and a second contact portion between a head part of the screw and the top cover, wherein the slip mechanism comprises a lubricant applied to the first and second contact portions, a first oil receiving groove formed in the top cover proximate the first contact portion, and a second oil receiving groove formed in the top cover proximate the second contact portion.