Patent · US Expired

Bearing structure

US5628571A · kind A · utility

7Cited by
4References
13Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 15, 1995
Grant dateMay 13, 1997
Priority date
Expiry dateSep 15, 2015

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF16C2370/12
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A bearing structure used in a pivot bearing for freely supporting the rotation of a head arm of a hard disk drive (HDD). The bearing structure includes an inner shaft, an outer sleeve, a pair of roller bearings axially spaced and interposed between the inner shaft and the outer sleeve, and a preload spring for exerting a preload on the roller bearings. The roller bearings may be provided with an outer race that is attached to the outer sleeve. Nevertheless, the coefficients of linear expansion of the inner shaft and the outer sleeve are chosen so that they are different in an axial direction. Accordingly, the coefficients of linear expansion of the inner shaft and the outer sleeve are chosen so that the rotation torque derived from the preload becomes higher as the temperature rises and lower as the temperature falls. However, the rotational torque becomes lower as the temperature of a lubricant rises and higher as the lubricant temperature falls. Thus, the changes in the rotational torque as a result of temperature change are cancelled out.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.