Magnetic disk drive and magnetic disk drive control
US7133242B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 25, 2005 |
| Grant date | Nov 7, 2006 |
| Priority date | — |
| Expiry date | May 25, 2025 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B19/06
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Embodiments of the invention provide a magnetic disk drive and magnetic disk drive control method for unloading a head safely with a simple configuration when a positioning control signal cannot be detected due, for instance, to a seek error. In one embodiment, when a head cannot detect servo information prerecorded on a disk, a positioning control section resets and starts a time counting section, and switches to an unloading control section for causing the unloading control section to output a position control signal to a VCM driver. The time counting section counts tacho-pulses generated by a motor driver, and outputs time information. The unloading control section receives the time information from the time counting section. In accordance with the received time information, the unloading control section computes the position control signal that the positioning control section outputs to the VCM driver. In this instance, the unloading control section controls the VCM driver to provide such an electrical current profile that the drive current to be supplied to a VCM is small at an initial stage and large at a later stage.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.