US6825411B2
Expired / Lapsed
US
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Method and apparatus for controlling electromagnetic radiation emissions from electronic device enclosures
Assignee: Hewlett Packard Enterprise Development LP
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Filing: 2003-05-06
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Granted: 2004-11-30
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Expires: 2023-05-06
Abstract
Abstract A method and apparatus is provided for reducing electromagnetic radiation emissions. The method and apparatus of the present invention also reduce or prevent electromagnetic radiation generated by sources outside of a system assembly from interfering with and adversely affecting electrical circuits in the assembly. An electromagnetic compatibility (EMC) solution uses a lossy element, and/or an element comprised of a combination of lossy and conductive material.
Inventors
- 👤 David Pommerenke
- 👤 David Dickey
- 👤 James J DeBlanc
- 👤 Victoria Tsang
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 00:31
CPC Classifications
H; H05; H05K; H05K9/00; H05K9/0007; H05K9/0015
Claims Analysis
Total Claims: 36
Claim 1
Independent Claim
126 words
An assembly, comprising: an enclosure having opposing side walls, a top, and a bottom; a module configured to integrate with the enclosure, the module having opposing side walls, a top, and a bottom, that surround electrical circuitry, wherein the module is partially surrounded by the enclosure such that a gap is formed between an outer surface of the module and an inner surface of the enclosure along an opening of the enclosure formed by adjacent edges of the opposing side walls, the top, and the bottom of the enclosure; a low-impedance contact disposed between an outer surface of the module and an inner surface of the enclosure, wherein the low-impedance contact electrically couples the module to the enclosure; and a lossy element disposed in the gap.
Claim 2
Dependent Claim
126 words
An assembly, comprising: an enclosure having opposing side walls, a top, and a bottom; a module configured to integrate with the enclosure, the module having opposing side walls, a top, and a bottom, that surround electrical circuitry, wherein the module is partially surrounded by the enclosure such that a gap is formed between an outer surface of the module and an inner surface of the enclosure along an opening of the enclosure formed by adjacent edges of the opposing side walls, the top, and the bottom of the enclosure; a low-impedance contact disposed between an outer surface of the module and an inner surface of the enclosure, wherein the low-impedance contact electrically couples the module to the enclosure; and a lossy element disposed in the gap.
Claim 3
Dependent Claim
41 words
The assembly of claim 1 , wherein a portion of the module and the enclosure that substantially overlap the low-impedance contact are manufactured with materials selected from the group consisting of metal, conductive plastic, or plastic with a thin metallization layer.
Claim 4
Dependent Claim
45 words
The assembly of claim 1 , wherein the low-impedance contact has a length that is at least one-fourth the wavelength of a transition frequency, wherein electromagnetic energy of frequencies approximately below the transition frequency are substantially prevented from traversing the gap via conventional electrical conduction.
Claim 5
Dependent Claim
19 words
The assembly of claim 1 , wherein the lossy element is fixed to an outer surface of the module.
Claim 6
Dependent Claim
19 words
The assembly of claim 1 , wherein the lossy element is fixed to an inner surface of the enclosure.
Claim 7
Dependent Claim
21 words
The assembly of claim 1 , wherein the lossy element has a depth that approximates the length of the low-impedance contact.
Claim 8
Dependent Claim
21 words
The assembly of claim 1 , wherein the lossy element comprises a material that both absorbs and reflects high-frequency electromagnetic energy.
Claim 9
Dependent Claim
18 words
The assembly of claim 1 , wherein the lossy element comprises a sheet manufactured from a dielectrically-lossy polyethylene.
Claim 10
Dependent Claim
18 words
The assembly of claim 1 , wherein the lossy element comprises a pad manufactured from a dielectrically-lossy polyethylene.
Claim 11
Dependent Claim
21 words
The assembly of claim 1 , wherein the enclosure further comprises a transverse internal wall configured with at least one opening.
Claim 12
Dependent Claim
14 words
The assembly of claim 1 , wherein the lossy material comprises a dielectrically-lossy polyethylene.
Claim 13
Dependent Claim
50 words
The assembly of claim 2 , wherein the low-impedance contact has a length that is at least one-fourth the wavelength of a transition frequency, wherein electromagnetic energy of frequencies approximately above the transition frequency are substantially prevented from traversing the gap by being reflected and attenuated by the lossy material.
Claim 14
Dependent Claim
17 words
The assembly of claim 7 , wherein the lossy element comprises a material that is electrically conductive.
Claim 15
Dependent Claim
24 words
The assembly of claim 10 , wherein the transverse internal wall comprises a layer of lossy material on the surface adjacent to the module.
Claim 16
Dependent Claim
27 words
The assembly of claim 11 , wherein the lossy material comprises a material selected from the group consisting of conductive polyethylene, conductive rubber and magnetically-filled silicon rubber.
Claim 17
Dependent Claim
13 words
The assembly of claim 13 , wherein the lossy element comprises a gasket.
Claim 18
Dependent Claim
63 words
An assembly, comprising: means for preventing electromagnetic energy of a frequency approximately below a transition frequency from traversing a gap formed by the outer surface of a module and the inner surface of an enclosure, wherein the module surrounds electrical circuitry generating the electromagnetic energy; and means for preventing electromagnetic energy of a frequency approximately above a transition frequency from traversing the gap.
Claim 19
Dependent Claim
63 words
An assembly, comprising: means for preventing electromagnetic energy of a frequency approximately below a transition frequency from traversing a gap formed by the outer surface of a module and the inner surface of an enclosure, wherein the module surrounds electrical circuitry generating the electromagnetic energy; and means for preventing electromagnetic energy of a frequency approximately above a transition frequency from traversing the gap.
Claim 20
Dependent Claim
36 words
The assembly of claim 17 , wherein the means for preventing electromagnetic energy of a frequency approximately below the transition frequency from traversing the gap comprises an electrically conductive path from the module to the enclosure.
Claim 21
Dependent Claim
35 words
The assembly of claim 18 , wherein the means for preventing electromagnetic energy of a frequency approximately above the transition frequency from traversing the gap comprises disposing at least one lossy element in the gap.
Claim 22
Dependent Claim
35 words
The assembly of claim 18 , wherein the electrically conductive path from the module to the enclosure comprises a low-impedance contact that substantially overlaps an electrically conductive portion of both the module and the enclosure.
Claim 23
Dependent Claim
27 words
The assembly of claim 19 , wherein the lossy element comprises a material selected from the group consisting of conductive polyethylene, conductive rubber and magnetically-filled silicon rubber.
Claim 24
Dependent Claim
24 words
The assembly of claim 20 , wherein the low-impedance contact has a length that is at least one-fourth the wavelength of the transition frequency.
Claim 25
Independent Claim
69 words
A method for controlling electromagnetic interference, comprising the steps of: providing a low-impedance contact to electrically couple an electrically conductive assembly enclosure to an electrically conductive module, the enclosure partially surrounding the module, wherein the module surrounds electromagnetic emitting circuits; and introducing at least one lossy element in a channel formed by the inner surfaces of the assembly enclosure, the outer surfaces of the module, and the low-impedance contact.
Claim 26
Independent Claim
69 words
A method for controlling electromagnetic interference, comprising the steps of: providing a low-impedance contact to electrically couple an electrically conductive assembly enclosure to an electrically conductive module, the enclosure partially surrounding the module, wherein the module surrounds electromagnetic emitting circuits; and introducing at least one lossy element in a channel formed by the inner surfaces of the assembly enclosure, the outer surfaces of the module, and the low-impedance contact.
Claim 27
Dependent Claim
45 words
The method of claim 23 , wherein the low-impedance contact has a length that is at least one-fourth the wavelength of a transition frequency, wherein electromagnetic energy of frequencies approximately below the transition frequency are substantially prevented from traversing the channel via conventional electrical conduction.
Claim 28
Dependent Claim
49 words
The method of claim 23 , wherein the low-impedance contact has a length that is at least one-fourth the wavelength of a transition frequency, wherein electromagnetic energy of frequencies approximately above the transition frequency are prevented from traversing the channel by being reflected and attenuated by the lossy material.
Claim 29
Dependent Claim
59 words
An assembly, comprising: an enclosure having opposing side walls, a top, and a bottom that surround electrical circuitry, wherein the enclosure comprises an opening formed by adjacent edges of at least one of the opposing side walls, the top, and the bottom of the enclosure; and a composite material that is dielectrically-lossy and electrically conductive disposed in the opening.
Claim 30
Dependent Claim
59 words
An assembly, comprising: an enclosure having opposing side walls, a top, and a bottom that surround electrical circuitry, wherein the enclosure comprises an opening formed by adjacent edges of at least one of the opposing side walls, the top, and the bottom of the enclosure; and a composite material that is dielectrically-lossy and electrically conductive disposed in the opening.
Claim 31
Dependent Claim
21 words
The assembly of claim 26 , wherein a portion of the enclosure overlaps at least a portion of the composite material.
Claim 32
Dependent Claim
16 words
The assembly of claim 26 , wherein the composite material both absorbs and reflects electromagnetic energy.
Claim 33
Dependent Claim
25 words
The assembly of claim 28 , wherein the composite material is selected from the group consisting of conductive polyethylene, conductive rubber and magnetically-filled silicon rubber.
Claim 34
Dependent Claim
13 words
The assembly of claim 28 , wherein the composite material comprises a gasket.
Claim 35
Dependent Claim
30 words
The assembly of claim 26 , wherein the composite material is manufactured with materials selected from the group consisting of metal, conductive plastic, or plastic with a thin metallization layer.
Claim 36
Dependent Claim
22 words
The assembly of claim 28 , wherein electromagnetic energy having frequencies above a transition frequency are substantially prevented from traversing the opening.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2007-11-30 | 2008-05-31 | 2008-11-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2011-11-30 | 2012-05-31 | 2012-11-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2015-11-30 | 2016-05-31 | 2016-11-30 | $7700.00 | Window Closed / Lapsed |