Phase and period synchronization for a slave disk drive
US5159503A · kind A · utility
Assignees
Inventors
Key dates
| Filing date | May 31, 1990 |
| Grant date | Oct 27, 1992 |
| Priority date | — |
| Expiry date | May 31, 2010 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B2220/20
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
In a system equipped with a plurality of magnetic disk devices, one magnetic disk device is used as a device (master unit) for generating reference signals for rotating other plurality of devices in synchronism. Other one or more magnetic disk devices (slave units) are rotated in synchronism following the reference signals generated from the master unit. In order to maintain the synchronism of revolution between the master unit and the slave units, the conditions of revolution of the two spindle motors are compared to maintain the synchronism of revolution. Index pulses recorded on the magentic disks of the master unit and the slave units are used as reference signals for maintaining synchronism of revolutions. Index pulses from the master unit and the slave units are compared to find a phase difference signal and a period difference signal, and the rotational speed of the slave units is compensated by using these two signals.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.