Disc drive spindle motor with rotor isolation and controlled resistance electrical pathway from disc to ground
US5729404A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 6, 1996 |
| Grant date | Mar 17, 1998 |
| Priority date | — |
| Expiry date | Mar 6, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02K11/40
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A disc drive for storing and retrieving data from at least one memory storage disc includes a drive base and a spindle motor. The spindle motor includes a rotor hub, a shaft, a bearing unit. The bearing unit rotatably supports the rotor hub about an axis. A controlled resistance electrical pathway is established from the rotor hub to ground to control disc potential and to prevent excess static charge buildup. In one embodiment, the spindle motor includes structural elements made of a conducting plastic having a controlled resistance to establish a controlled resistance electrical pathway from the rotor hub to ground. In a second embodiment, the shaft of the spindle motor includes a conductive contact button electrically connected to the shaft and operatively coupled with a contact shield electrically grounded by an electrical conductor having a controlled resistance. In another embodiment, the spindle motor includes a rod made of conductive material extending from an electrically grounded contact shield and received within the shaft. An electrical pathway between the shaft and the rod is established by a conducting fluid between the rod and the shaft. Alternatively, the electrical…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.