Fluid dynamic bearing device
US8926183B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 28, 2012 |
| Grant date | Jan 6, 2015 |
| Priority date | — |
| Expiry date | Feb 28, 2032 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16C2370/12
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
An inner peripheral surface and a lower end surface of a bearing sleeve made of a sintered metal are each formed into a smooth cylindrical surface or a flat surface that does not have a dynamic pressure generating portion. Thus, a step of forming the dynamic pressure generating portion can be omitted from a manufacturing step of the bearing sleeve, and cost of dies can be markedly reduced. Further, the inner peripheral surface of the bearing sleeve is formed into the smooth cylindrical surface, and hence a radial dynamic pressure generating portion is formed on an outer peripheral surface of a shaft member. However, the outer peripheral surface of the shaft portion is accessible to tools, and hence the radial dynamic pressure generating portion can be formed easily with high accuracy. As a result, accuracy of a radial bearing gap is enhanced so that a bearing rigidity is enhanced.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.