Thermo servo for track centering on a disk
US4814908A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Dec 3, 1986 |
| Grant date | Mar 21, 1989 |
| Priority date | — |
| Expiry date | Dec 3, 2006 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B5/4873
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An apparatus and method for positioning a transducer over the center of a track is disclosed. An arm carries the transducer. Embedded in the arm is a heating element. The heating element is positioned so that the linear expansion or contraction of the arm resulting from the temperature rise or drop due to the amount of heat applied to the arm by the heating element will move the transducer across the track. In operation, a constant amount of heat is initially applied to the arm to center the transducer. During tracking, a circuit varies the amount of power applied to the heating element so that the transducer is kept over the center of the track.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.