Radial pumping oil seal for fluid dynamic bearing motor
US7234868B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 30, 2003 |
| Grant date | Jun 26, 2007 |
| Priority date | — |
| Expiry date | Jan 30, 2024 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16C33/74
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
An improved rotational motor, such as a spindle motor for a disc drive, is provided. The motor first comprises a hub having a shaft portion and a horizontal body portion. The motor also comprises a sleeve surrounding the shaft portion of the hub. A fine first vertical gap is retained between the shaft and the inner diameter of the surrounding sleeve. In addition, a fine horizontal gap is provided between the upper hub portion and the top of the sleeve. A third gap is preferably provided between the hub and an outer diameter of the sleeve. The first vertical gap is filled with a lubricating liquid, such as a clean oil. A capillary seal is provided in the third gap. In one embodiment, the lubricating liquid extends into the horizontal gap. Oil pumping grooves are machined along the horizontal fluid gap. When the hub is rotated, the oil pumping grooves impel oil towards the shaft. This prevents any portion of the first vertical gap from becoming un-lubricated during rotation of the shaft.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.