Spindle-drive motor with a magnetic fluid seal
US6543781B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 29, 2000 |
| Grant date | Apr 8, 2003 |
| Priority date | — |
| Expiry date | Dec 7, 2020 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16C2370/12
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A spindle-drive motor for hard drives having a baseplate, a shaft and one or more bearings for rotational mounting of a rotationally driven rotor, with at least one magnetic fluid seal arranged between the stationary part and the rotating part of the spindle-drive motor. The seal is formed of an upper and a lower yoke lamination and a magnet disk arranged between the yoke laminations, where a concentric chamber is formed so that it is open toward the inside on one side to hold a magnetically conducting fluid. A flux concentrating lamination extends into this chamber. In one embodiment of this invention, the flux concentrating lamination is in direct or indirect contact with one end face of the inner bearing ring of the bearing, while the outer part of the magnetic fluid seal is in direct or indirect contact with the end face of the outer bearing ring of the bearing. In another embodiment, the flux concentrating lamination on the inside is in direct or indirect contact with a radial reference shoulder of the shaft.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.