Patent · US Expired

RF shield for circuit card having a solid first flange

US5774344A · kind A · utility

69Cited by
6References
18Claims
0Family size

Assignee

Inventor

Key dates

Filing dateDec 6, 1995
Grant dateJun 30, 1998
Priority date
Expiry dateDec 6, 2015

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH05K9/0037
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A metallized plastic RFI/EMI shield is provided against electromagnetic energy for a circuit card wherein the shield is formed of a box enclosure with two casing halves to enclose the card, the first casing half having a solid flange side walls surrounding the card and the second casing half having a flange formed by flat, plate-like closely-spaced fingers, the fingers confronting, being in electrical contact with and mating in full length with substantially the entire periphery of the side walls of the first casing half. The fingers are preferably spaced with a separation of less than 1/4 wavelength of any measurable harmonic of the intended operating frequency, typically up to the tenth harmonic. A slot may be provided to receive the fingers on the outside of the side walls, and closely-spaced grounding pins arranged around the periphery of the card may extend between the first and second casing halves through ground plated perforations along the edge of the side walls.

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