Automatic head retract system for disk drive
US4786995A · kind A · utility
73Cited by
7References
15Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Nov 6, 1986 |
| Grant date | Nov 22, 1988 |
| Priority date | — |
| Expiry date | Nov 6, 2006 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B21/12
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An automatic head retract system for a disk drive is disclosed which operates in response to electric power turn off to retract the heads to a landing zone on the disk surface. The heads are retracted by operating a positioner motor under the control of logic internal to the disk drive unit without intervention by a host computer. The positioner motor comprises a multiphase DC brushless motor which, after power loss, is supplied with current from a capacitor charged during normal drive usage and by the back EMF of a spindle motor. A latch mechanically locks the heads in the landing zone.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.