Patent · US Expired

Fluid dynamic-pressure bearing device and spindle motor

US7290934B2 · kind B2 · utility

7Cited by
3References
20Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 8, 2005
Grant dateNov 6, 2007
Priority date
Expiry dateApr 7, 2026

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH02K7/085
  • WIPO fieldMechanical elements
  • WIPO sectorMechanical engineering

Abstract

Small-size, small-height fluid dynamic-pressure bearing device that causes a low shaft loss and is less prone to troubles such as shortage and leakage of lubricating liquid. A thrust dynamic-pressure bearing is formed at an inner position and a region having a slightly-widened gap is provided outside of the thrust dynamic-pressure bearing to retain the lubricating liquid therein. Further, an oil circulating path is communicated with the region having a slightly widened gap. The gap of this region is set to be greater than the gap at the thrust dynamic-pressure bearing portion by the value of the depth of dynamic-pressure generating grooves. The region having a widened gap may be provided with rows of grooves for stirring-up lubricating oil towards the center.

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