Patent · US Expired

Magnetic shield for visual display terminals

US4992624A · kind A · utility

6Cited by
3References
11Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 12, 1989
Grant dateFeb 12, 1991
Priority date
Expiry dateJun 12, 2009

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01F27/36
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A magnetic shield is designed to be retrofitted over a flyback transformer of a cathode ray tube display terminal. The magnetic shield consists of a layer of metal conductor, for example mu metal, and a layer of insulation, for example polyester film. The layer of insulation is placed upon the layer of metal conductor and the layers are rolled to form a spiral having greater than two windings. Tape may be used to secure the shape of the spiral. Additionally foam rubber pads may be attached to the inside of the spiral to provide a secure mechanical mounting to the flyback transformer and to provide air spacing as additional insulation against corona discharge. Also shrink tubing may be placed over the spiral to provide additional support to the spiral shape and to provide heat and electrical insulation.

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