Dynamic pressure type fluid bearing device
US4934836A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 14, 1989 |
| Grant date | Jun 19, 1990 |
| Priority date | — |
| Expiry date | Aug 14, 2009 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16C17/107
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A housing has a vertically extending cylindrical bore, with a radical bearing surface formed on the inner peripheral surface, and a thrust bearing surface formed on the inner bottom surface of the cylindrical bore. A shaft member which is supported rotatably in the cylindrical bore of the housing has a radial receiving surface and a thrust receiving surface respectively formed on the outer peripheral surface and the bottom surface. A dynamic pressure generating groove of a spiral shape is formed in at least one of the radial bearing surface and ther radial receiving surface. When the shaft member is rotated, a gas in the housing is sucked by the pumping action of the dynamic pressure generating groove and flows into a pressure chamber between the thrust bearing surface and the thrust receiving surface through a radial space between the radial bearing surface and the radial receiving surface. The pressure in the pressure chamber maintains the shaft member in a floating position by a predetermined amount. The shaft member has a passage bore formed along a center axis line. The passage bore includes a restricted aperture of a smaller diameter which opens at the thrust receiving surfac…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.