"Method for positioning head in disk drive deriving ""position"" offset from ""quadrature"" signals"
US4797756A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 5, 1987 |
| Grant date | Jan 10, 1989 |
| Priority date | — |
| Expiry date | Mar 5, 2007 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B5/59627
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
For a disk drive servo system using position and position-quadrature signals (P, Q), a method for automatically effecting "Absolute Track Registration" and compensating for "offsets" by using the peak position of one of signals (P or Q) to find "true" position (true offset) for the other (Q or P) wherein the R/W actuator is brought to rest at a reference position and sample-offset signal generated; while the corresponding magnitude of related positioning signals are detected--this being repeated until the peak values of said positioning signals is located whereupon the corresponding position-offset is derived as "true offset"--the actuator then being repositioned by this "true offset" value; and repeating this for a given number of track sites across the disk.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.