Recording method, unload method, and magnetic disk
US7636218B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 27, 2007 |
| Grant date | Dec 22, 2009 |
| Priority date | — |
| Expiry date | Jul 9, 2028 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B21/12
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Embodiments of the present invention prevent occurrence of a write pole erasure in the event of a power failure within a magnetic disk apparatus of a perpendicular magnetic recording system. According to one embodiment of the present invention, a recording current is flowed through a magnetic head to record data in a magnetic disk. An occurrence of a power failure in the magnetic disk apparatus is detected. When a power failure has occurred, the recording head is demagnetized with power in case of a power failure. The recording head is unloaded after the recording head has been demagnetized. For the power in case of a power failure, back electromotive force of a spindle motor can be utilized. As a result, effects exerted on data recorded in the magnetic disk due to residual magnetism remaining in the recording head can be eliminated.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.