Dummy write method for a magnetic head and drive unit for carrying out the method
US6441982B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 24, 1999 |
| Grant date | Aug 27, 2002 |
| Priority date | — |
| Expiry date | Nov 24, 2019 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B2005/0021
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A drive unit which recovers from write instability by heating the magnetic head prior to performing a dummy write operation is described. In the preferred embodiments, once write instability has been detected the head may be heated by friction with the rotating disk or by an external heater. In the friction method the head is moved to a safe area of the disk such as a textured landing zone while the disk rotation is continued. In drives using unload ramps, a heater is preferably placed at the the ramp so that the head can be heated while parked on the ramp. In each of these embodiments dummy write operations are performed while the head is in a thermally excited state due to the heating. The combination of heating and the dummy write operation aids in restoring write stability.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.