Brushless motor
US5610462A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 20, 1994 |
| Grant date | Mar 11, 1997 |
| Priority date | — |
| Expiry date | Jun 20, 2014 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02K5/124
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
There is disclosed a brushless motor in which an oil-impregnated sleeve bearing is inserted in a bearing holder having a cylindrical shape with a closed bottom, and a rotating shaft is inserted in the oil-impregnated sleeve bearing in such a manner that the rotating shaft may freely rotate. With this arrangement, it becomes possible to prevent lubricant from leaking out without increasing either the number of component elements or the number of assembling steps. The oil-impregnated sleeve bearing comprises an inner and outer layers. An oil seat is disposed on the oil-impregnated sleeve bearing at the open-end side of the bearing holder. The percentages of voids are set such that the percentages of voids become lower in the order of the oil seal, the outer layer, and the inner layer. With the above arrangement, the lubricant can be prevented from leaking out through a gap of the bearing, and therefore reduction of life due to the leakage of lubricant can also be prevented.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.