Patent · US Expired

Hydrodynamic bearing and disc rotation apparatus using the same

US7237955B2 · kind B2 · utility

2Cited by
3References
4Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 2, 2003
Grant dateJul 3, 2007
Priority date
Expiry dateJun 12, 2025

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF16C2370/12
  • WIPO fieldMechanical elements
  • WIPO sectorMechanical engineering

Abstract

A high-accuracy, long-life hydrodynamic bearing that does not cause oil film breakage in bearing clearances and a disc rotation apparatus using the bearing is disclosed. Oil film breakage is avoided as negative pressure is prevented from generating between the shaft and sleeve of the hydrodynamic bearing. Herringbone shaped dynamic pressure generating grooves, located on the thrust bearing section and the radial bearing section of the hydrodynamic bearing, are oil filled and have optimum shapes. The optimum shapes prevent the generation negative pressure and thus prevents the coagulation of air bubbles that can cause oil film breakage. The disc rotation apparatus, that holds a reproduction/recording disc, is concentrically secured to the hydrodynamic bearing and rotated. The disc is put into contact with magnetic or optical heads while rotating in the disc rotation apparatus. Both the hydrodynamic bearing and the disc rotation apparatus experience high reliability.

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