Patent · US Expired

Transient magnet field degaussing system

US5969933A · kind A · utility

14Cited by
25References
39Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 25, 1998
Grant dateOct 19, 1999
Priority date
Expiry dateMar 25, 2018

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11B5/0245
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A means for winding orthogonal coil systems that almost completely encompass and closely conform to magnetic media having a circular cylindrical form and orientation, including such media further encased in square or rectangular cassettes, cartridges or disk drives, while providing necessary access to that volume without the use of drawers and separable connectors or flexible lead wires for connection of the coils to energy stored in capacitors. The invention further employs hard wired circuitry for controlling the phase of currents in the coils and maintaining the desired rotation of the magnetic field. While this invention can be realized to degauss media inserted and extracted through the same side of the winding system, it is equally configurable to conveyance of media in one end of an orthogonal coil system and out of the opposing end. In one embodiment of this invention, the media size is measured for the purpose of positioning it properly for degaussing an entire media unit such as a tape reel, such positioning being limited to at most two positions for the case of rectangular housings such as tape cassettes that contain two reels or disk drives with disks on one end and hea…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.