WO1988008610A1 - Flexible free-breathing radio frequency insulator with magnetic diffusion characteristics - Google Patents

Flexible free-breathing radio frequency insulator with magnetic diffusion characteristics Download PDF

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Publication number
WO1988008610A1
WO1988008610A1 PCT/US1988/001256 US8801256W WO8808610A1 WO 1988008610 A1 WO1988008610 A1 WO 1988008610A1 US 8801256 W US8801256 W US 8801256W WO 8808610 A1 WO8808610 A1 WO 8808610A1
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WO
WIPO (PCT)
Prior art keywords
particles
energy
magnetic
iron
medium
Prior art date
Application number
PCT/US1988/001256
Other languages
French (fr)
Inventor
David M. Barrett
Original Assignee
Barrett David M
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Barrett David M filed Critical Barrett David M
Publication of WO1988008610A1 publication Critical patent/WO1988008610A1/en

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Classifications

    • HELECTRICITY
    • H05ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05KPRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
    • H05K9/00Screening of apparatus or components against electric or magnetic fields
    • H05K9/0073Shielding materials
    • H05K9/0081Electromagnetic shielding materials, e.g. EMI, RFI shielding
    • H05K9/009Electromagnetic shielding materials, e.g. EMI, RFI shielding comprising electro-conductive fibres, e.g. metal fibres, carbon fibres, metallised textile fibres, electro-conductive mesh, woven, non-woven mat, fleece, cross-linked
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01BCABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
    • H01B1/00Conductors or conductive bodies characterised by the conductive materials; Selection of materials as conductors
    • H01B1/20Conductive material dispersed in non-conductive organic material
    • H01B1/22Conductive material dispersed in non-conductive organic material the conductive material comprising metals or alloys
    • HELECTRICITY
    • H05ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05KPRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
    • H05K9/00Screening of apparatus or components against electric or magnetic fields
    • H05K9/0073Shielding materials
    • H05K9/0081Electromagnetic shielding materials, e.g. EMI, RFI shielding
    • H05K9/0083Electromagnetic shielding materials, e.g. EMI, RFI shielding comprising electro-conductive non-fibrous particles embedded in an electrically insulating supporting structure, e.g. powder, flakes, whiskers

Definitions

  • This invention relates to materials designed to shield electronic circuits. Such shields protect sensitive electronic circuits from RF energy, and magnetic energy. These shields, often referred to as insulators, fall into two basic types of shields:
  • Such devices as in category 1 usually require grounding and thus themselves may be subject to propogating any varying references in the ground circuit.
  • Such devices as in category 2 are usually bulky, if not heavy.
  • the herein-described invention purports to eliminate or alleviate the aforementioned limitations by providing a flexible, free-breathing, RF insulation material with uniform magnetic diffusion characteristics.
  • This device begins with a thin, flexible sheet saturated with or simply made from non-woven fibers of a conductive metal such as aluminum, held in place with a resin or adhesive medium, serving as a conductive base.
  • This conductive base is then perforated with parallel cylindrical holes placed at a precise angle to the surface of the sheet, preferably 45 degrees, the diameter of said holes being less than the thickness of the sheet.
  • the performations therein are required to be in close proximity to each other, both for passage of air through the insulator and for space for adherence of the coatings, as well as for lightness of weight.
  • the performated sheet is then coated with a very dense suspension of ultra-fine iron and copper powders and finally with an exterior fixative.
  • the sheet is now a flexible insulator for RF energy and magnetic force, including ELF.
  • This material can now be cut and shaped to be worn near a pacemaker, placed adjunct to printed circuit boards, to surround an electric motor or generator, and/or to insulate an area from an RF generator.
  • the device consists of a thin, flexible sheet of a material which functions as an insulator for RF energy and magnetic force, including ELF. It can be used much as a heavy fabric, using the operations of cutting, seaming, sewing, etc., to give it whatever shape is appropriate to the insulation job needed.
  • a sheet of the device can be used to cover RF energy sources such as generators, motors, microwave ovens r televisions, computers, etc., many of which exhibit strong magnetic fields when their operation is stymied, to keep such energy from being broadcast into the environment.
  • RF energy sources such as generators, motors, microwave ovens r televisions, computers, etc.
  • the material is air-breathing, which means that it will not trap heat inside such RF or ELF sources, most of which require air cooling and cannot use a non-breathing insulator.
  • a sheet of the device can be used to cover items which are sensitive to RF and/or ELF energies to insulate them from such energies in their current environment.
  • items which are sensitive to RF and/or ELF energies to insulate them from such energies in their current environment.
  • Such items are computers, pacemakers, and electronic testing equipment.
  • no ground wires or cables are required, due to the high molecular density and relatively small size of the iron component and the conducting abilities of the aluminum and copper components.
  • the air-breathing facility of the device allows air flow for cooling of electronic devices, while reducing the overall weight of the material.

Abstract

In an RF energy insulating material device, the establishing of component relations, those of iron, copper, and aluminum, through their molecular qualities, provides a device which is consistent in its magnetic diffusion qualities sufficiently to function as an ELF and magnetic force insulator concurrently, while providing for the free passage of air through this material for the cooling of the source of said energies, while being flexible and of light weight. The iron component in the relationship is in heavy concentration though suspended in separate positions throughout the medium, while the copper component is in larger particles but occurs far less frequently, and the aluminum component is interwoven in long strands throughout the medium to provide electrical conductivity in RF dispersement. This provides an RF insulator which can diffuse magnetism for the purposes of directly protecting delicate electronic equipment from both RF energy and magnetic force, and containment of such forces from their sources.

Description

FLEXIBLE FREE-BREATHING RADIO FREQUENCY INSULATOR WITH MAGNETIC DIFFUSION CHARACTERISTICS
DESCRIPTION OP PRIOR ART
This invention relates to materials designed to shield electronic circuits. Such shields protect sensitive electronic circuits from RF energy, and magnetic energy. These shields, often referred to as insulators, fall into two basic types of shields:
(1) those which insulate the environment against a source of such energy or energies; and
(2) those which insulate a given object against any such energy or energies already in the environment.
Much of the literature discusses materials which will serve in one or the other of these capacities with radio frequency energy or microwave energy, but none seems to deal with either the insulation against magnetic forces, including ELF, in detail, especially in the case of simultaneous occurrence of RF energy and ELF, now being called an "intensified field" effect in the literature, or with materials which are appropriate as insulators in both categories.
Such devices as in category 1 usually require grounding and thus themselves may be subject to propogating any varying references in the ground circuit.
Such devices as in category 2 are usually bulky, if not heavy.
Devices in both categories do not seem to facilitate the passage of coolants beyond the cooling of the RF insulating material itself.
Most such devices operate on a reflective principle, wherein they present a solid surface which reflects or deflects the RF energy from its original path. Further, when such devices are utilized as insulators or diffusers of magnetic energy, they generally contain large amounts of iron in solid form in their composition, and thus are very heavy. DESCRIPTION OF PRIOR ART, CONTINUED
Prior devices in both categories are not, for the most part, lexible.
The current literature indicates that we should take into consideration the increased antenna effect of a pacemaker or the parallel circuitry of a printed circuit board when it is in the vicinity of ELF or a magnetic field, because the existence of a magnetic field, when penetrated by RF energy, creates a condition referred to as an intensified field. While the previously-mentioned insulators are satisfactory in their ability to insulate, for the most part they do not lend themselves to removal and reuse, nor to conforming with various structural shapes.
The herein-described invention purports to eliminate or alleviate the aforementioned limitations by providing a flexible, free-breathing, RF insulation material with uniform magnetic diffusion characteristics.
DESCRIPTION OF THE INVENTION
This device begins with a thin, flexible sheet saturated with or simply made from non-woven fibers of a conductive metal such as aluminum, held in place with a resin or adhesive medium, serving as a conductive base. This conductive base is then perforated with parallel cylindrical holes placed at a precise angle to the surface of the sheet, preferably 45 degrees, the diameter of said holes being less than the thickness of the sheet. The performations therein are required to be in close proximity to each other, both for passage of air through the insulator and for space for adherence of the coatings, as well as for lightness of weight. The performated sheet is then coated with a very dense suspension of ultra-fine iron and copper powders and finally with an exterior fixative. The sheet is now a flexible insulator for RF energy and magnetic force, including ELF.
This material can now be cut and shaped to be worn near a pacemaker, placed adjunct to printed circuit boards, to surround an electric motor or generator, and/or to insulate an area from an RF generator.
OPERATION
The device consists of a thin, flexible sheet of a material which functions as an insulator for RF energy and magnetic force, including ELF. It can be used much as a heavy fabric, using the operations of cutting, seaming, sewing, etc., to give it whatever shape is appropriate to the insulation job needed.
A sheet of the device can be used to cover RF energy sources such as generators, motors, microwave ovens r televisions, computers, etc., many of which exhibit strong magnetic fields when their operation is stymied, to keep such energy from being broadcast into the environment. The material is air-breathing, which means that it will not trap heat inside such RF or ELF sources, most of which require air cooling and cannot use a non-breathing insulator.
A sheet of the device can be used to cover items which are sensitive to RF and/or ELF energies to insulate them from such energies in their current environment. Among such items are computers, pacemakers, and electronic testing equipment. Unlike some other insulators for such things, no ground wires or cables are required, due to the high molecular density and relatively small size of the iron component and the conducting abilities of the aluminum and copper components. Once again the air-breathing facility of the device allows air flow for cooling of electronic devices, while reducing the overall weight of the material.
Obviously this invention is susceptible to changes or alterations without defeating its practicability. Therefore, I do not wish to be confined to the preferred embodiment shown and described in the accompanying drawing. Neither do I wish to be limited to the materials and respective quantities discussed in this description of the preferred embodiment. In a flexible, RF energy absorbing, magnetically diffusing material which is primarily utilized to protect sensitive electronic circuits from the effects of RF energy, magnetic force including ELF, and the combination of both in an intensified field,

Claims

I claim:
(1 ) A composite material comprised of non-combined elements placed in a spatial relationship in a containing medium to provide shielding from all forms of electro-magnetic energy energy.
(2) a device according to claim 1 in which: the non-combined elements are comprised of iron, copper, and aluminum.
(3) a device according to claim 2 in which: the iron component in this relationship is in heavy concentration though suspended in separate positions throughout the medium; the copper component is in larger particles but occurs far less frequently; the aluminum component is interwoven in long strands throughout the medium to provide electrical conductivity in RF dispersement.
(4) a device according to claim 1 in which: said composite material further provides for consistent magnetic diffusion by functioning as a linked magnetic conductor while dissipating the energy of a magnetic field.
(5) a device according to claim 1 in which: said material further constitutes a free passageway for the transportation of air through being multiply perforated. CLAIMS, CONTINUED
(6) a device according to claim 5 in which: the physical thickness of the material coincides with the angle of entry of its performations, so as to restrict all but the small percentage of the RF energy which presents itself to the line of sight passage of these perforations.
(7) a device according to claim 6 in which: said perforations are spaced in close proximity to each other.
(8) a device according to claim 3 in which: the presentation of iron particles is of a sufficient density that each particle will have within its own magnetic range several other such particles.
(9) a device according to claim 8 in which: the magnetic range of said particles is proportional to the square root of the physical size of the iron particles.
(10) a device according to claim 9 in which: the magnetic range is furthermore inversely proportional to the distance between said particles by the square of the distance between said particles.
(11) a device according to claim 8 in which: the optimum light physical weight of said material is contingent upon the reduced physical sizing of the iron particles in their proximity to being independent molecules. CLAIMS, CONTINUED
(12) In an electromagnetic energy-shielding material, s. sheet or plate of material comprised of an inherently flexible medium permeated with strands of electrically-conductive material, interspersed with a super-saturated suspension of ferrous molecular components in a medium, and particles of metallic material which exhibits an excess of "free" electrons;
(13-) a material according to claim 12 and furthermore, in a sheet form with permeations or holes, said sheet being of a physical thickness in excess of the diameter of said holes;
(14) a device according to claim 12: further including a random dispersement of highly conducting electrical strands, the density of which is such that said strands will frequently contact one another.
(15) a device according to claim 12 in which: said ferrous particles1 sizing is accomplished by dispelling the oxygen from ferric oxide particles.
(16) a device according to claim 12 in which: the material can achieve a temporary unified magnetization.
PCT/US1988/001256 1987-04-24 1988-04-22 Flexible free-breathing radio frequency insulator with magnetic diffusion characteristics WO1988008610A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US4244287A 1987-04-24 1987-04-24
US042,442 1987-04-24

Publications (1)

Publication Number Publication Date
WO1988008610A1 true WO1988008610A1 (en) 1988-11-03

Family

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Family Applications (1)

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PCT/US1988/001256 WO1988008610A1 (en) 1987-04-24 1988-04-22 Flexible free-breathing radio frequency insulator with magnetic diffusion characteristics

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AU (1) AU1796388A (en)
WO (1) WO1988008610A1 (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US8103356B2 (en) 2006-05-23 2012-01-24 Vertech, Inc. High frequency epidural neuromodulation catheter without needle for effectuating RF treatment

Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2858451A (en) * 1955-03-07 1958-10-28 Herman I Silversher Laminar ray shielding materials
US2877286A (en) * 1955-06-13 1959-03-10 Cs 13 Corp Radiant energy shielding device
US2977591A (en) * 1952-09-17 1961-03-28 Howard A Tanner Fibrous microwave absorber
US2985880A (en) * 1958-04-24 1961-05-23 Edward B Mcmillan Dielectric bodies for transmission of electromagnetic waves
US3441933A (en) * 1967-04-03 1969-04-29 Raytheon Co Radio frequency absorber
US4371742A (en) * 1977-12-20 1983-02-01 Graham Magnetics, Inc. EMI-Suppression from transmission lines
US4408255A (en) * 1981-01-12 1983-10-04 Harold Adkins Absorptive electromagnetic shielding for high speed computer applications
US4585901A (en) * 1984-02-13 1986-04-29 Pennwalt Corporation EMI/RFI vapor deposited composite shielding panel
US4664971A (en) * 1981-12-30 1987-05-12 N.V. Bekaert S.A. Plastic article containing electrically conductive fibers
US4684762A (en) * 1985-05-17 1987-08-04 Raychem Corp. Shielding fabric

Patent Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2977591A (en) * 1952-09-17 1961-03-28 Howard A Tanner Fibrous microwave absorber
US2858451A (en) * 1955-03-07 1958-10-28 Herman I Silversher Laminar ray shielding materials
US2877286A (en) * 1955-06-13 1959-03-10 Cs 13 Corp Radiant energy shielding device
US2985880A (en) * 1958-04-24 1961-05-23 Edward B Mcmillan Dielectric bodies for transmission of electromagnetic waves
US3441933A (en) * 1967-04-03 1969-04-29 Raytheon Co Radio frequency absorber
US4371742A (en) * 1977-12-20 1983-02-01 Graham Magnetics, Inc. EMI-Suppression from transmission lines
US4408255A (en) * 1981-01-12 1983-10-04 Harold Adkins Absorptive electromagnetic shielding for high speed computer applications
US4664971A (en) * 1981-12-30 1987-05-12 N.V. Bekaert S.A. Plastic article containing electrically conductive fibers
US4585901A (en) * 1984-02-13 1986-04-29 Pennwalt Corporation EMI/RFI vapor deposited composite shielding panel
US4684762A (en) * 1985-05-17 1987-08-04 Raychem Corp. Shielding fabric

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US8103356B2 (en) 2006-05-23 2012-01-24 Vertech, Inc. High frequency epidural neuromodulation catheter without needle for effectuating RF treatment

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Publication number Publication date
AU1796388A (en) 1988-12-02

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