Patent · US Expired

Automatic head retract system for disk drive

US4866554A · kind A · utility

28Cited by
3References
1Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 25, 1988
Grant dateSep 12, 1989
Priority date
Expiry dateJul 25, 2008

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. The system 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.