JP2737307B2 - Electromagnetic shielding - Google Patents
Electromagnetic shieldingInfo
- Publication number
- JP2737307B2 JP2737307B2 JP26987389A JP26987389A JP2737307B2 JP 2737307 B2 JP2737307 B2 JP 2737307B2 JP 26987389 A JP26987389 A JP 26987389A JP 26987389 A JP26987389 A JP 26987389A JP 2737307 B2 JP2737307 B2 JP 2737307B2
- Authority
- JP
- Japan
- Prior art keywords
- electromagnetic wave
- present
- electromagnetic
- cavities
- honeycomb structure
- Prior art date
- Legal status (The legal status 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 status listed.)
- Expired - Lifetime
Links
Landscapes
- Shielding Devices Or Components To Electric Or Magnetic Fields (AREA)
Description
【発明の詳細な説明】 〔産業上の利用分野〕 本発明は電子機器から放射される不要電磁波の抑制や
電磁遮へい室に使用して電磁波の漏洩、浸入を防止する
電磁波遮へい体に関し、特に放熱やケーブル類の貫通用
に設けられた開口部に使用する電磁波遮へい体に関す
る。DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to an electromagnetic wave shield used to suppress unnecessary electromagnetic waves radiated from an electronic device and to prevent leakage and intrusion of electromagnetic waves when used in an electromagnetic shielding room, and particularly to heat radiation. The present invention relates to an electromagnetic wave shield used for an opening provided for penetrating cables and cables.
従来、この種の電磁波遮へい体は、第３図（ａ）に示
すように金属などの良導体の板を格子状に配列した構造
体Ａとしたり、又は第３図（ｂ）に示すようにハニカム
構造体Ｂとして小さな開口を多数設けるようにしたもの
となっていた（例えば「電磁妨害と防止対策」東京電機
大学出版局）。Conventionally, this type of electromagnetic wave shielding member has a structure A in which plates of good conductors such as metal are arranged in a lattice as shown in FIG. 3 (a), or a honeycomb as shown in FIG. 3 (b). Many small openings were provided as the structure B (for example, “Electromagnetic interference and prevention measures”, Tokyo Denki University Press).
上述した従来の電磁波遮へい体は開口断面の寸法と形
状に依存して定まる電磁界モードの遮断領域における減
衰効果を利用したものであるため、十分な遮へい効果を
得るためには開口面積を小さくするか、あるいは開口部
の奥行きを増して導波路長を長くすることが必要であ
る。Since the above-mentioned conventional electromagnetic wave shielding body utilizes an attenuation effect in an electromagnetic field mode shielding region determined depending on the size and shape of the opening cross section, the opening area is reduced to obtain a sufficient shielding effect. Alternatively, it is necessary to increase the waveguide length by increasing the depth of the opening.
本発明の目的はハニカム構造の遮へい体において、同
一の開口面積と奥行きを有するにもかかわらず、遮へい
性能を向上せしめた電磁波遮へい体を提供することにあ
る。SUMMARY OF THE INVENTION An object of the present invention is to provide an electromagnetic wave shield having a honeycomb structure with improved shielding performance despite having the same opening area and depth.
上記目的を達成するため、本発明の電磁波遮へい体に
おいては、金属などの良導体により構成され、断面寸法
が波長に比べ十分小さく、断面形状が六角形の空胴を多
数並べたハニカム構造体において、前記空胴の壁面を高
透磁率材料にて被覆したものである。In order to achieve the above object, in the electromagnetic wave shield of the present invention, a honeycomb structure formed of a good conductor such as metal, the cross-sectional dimension is sufficiently smaller than the wavelength, and the cross-sectional shape is formed by arranging a number of hexagonal cavities, The cavity has a wall surface coated with a high magnetic permeability material.
ハニカム形電磁波遮へい体中の一空胴内の電磁界モー
ドは、その断面が正六角形であることから円筒導波管の
モードに近似して考えることができる。円筒導波管の基
体モードはTE11モードであり、遮断周波数より十分に低
い周波数帯での電磁波の減衰効果SEは円筒の半径をa,導
波路長をｄとして、SE＝8.69×２π×d/3.41a［dB］で
表わされる。この円筒導波管壁面を高透磁率材で覆った
場合の電磁界モードは空胴壁面において磁界が壁面に垂
直な成分のみを有するモードの中で最も次元の低いTE01
となる。このときの電磁波の減衰効果SEはSE＝8.69×２
π×d/3.41a［dB］で表わされ、減衰効果はdB表示で約3
0％増加する。The electromagnetic field mode in one cavity in the honeycomb-shaped electromagnetic wave shield can be considered to be similar to the mode of a cylindrical waveguide because its cross section is a regular hexagon. The base mode of the cylindrical waveguide is the TE 11 mode, and the electromagnetic wave attenuation effect S E in a frequency band sufficiently lower than the cutoff frequency is S E = 8.69 × 2π, where a is the radius of the cylinder and d is the waveguide length. × d / 3.41a [dB]. The electromagnetic field mode when this cylindrical waveguide wall is covered with a high permeability material is the lowest dimension TE 01 among the modes in which the magnetic field has only a component perpendicular to the wall on the cavity wall.
Becomes The electromagnetic wave attenuation effect S E at this time is S E = 8.69 × 2
π × d / 3.41a [dB], the attenuation effect is approximately 3 dB
Increase by 0%.
高透磁率材２はアモルファス磁性合金やパーマロイな
どの磁性合金，フェライトなどの磁性体及びこれらを線
状、もしくは片状とし、高分子材を用いてシート化した
もので構成されている。十分な減衰効果を得るためには
比透磁μｒは30以上あることが望ましい。高透磁率材２
の厚さは透磁率の大きさに依存するが実用上は0.01〜5m
mの範囲である。The high-permeability material 2 is made of a magnetic alloy such as an amorphous magnetic alloy or permalloy, a magnetic material such as ferrite, or a linear or flake-like material formed of a sheet made of a polymer material. In order to obtain a sufficient damping effect, the relative magnetic permeability μr is desirably 30 or more. High permeability material 2
Thickness depends on the degree of permeability, but practically 0.01 to 5 m
m.
次に本発明について図面を参照して説明する。 Next, the present invention will be described with reference to the drawings.
第１図は本発明の一実施例を示す斜視図である。 FIG. 1 is a perspective view showing one embodiment of the present invention.
図において、本発明は金属などの良導体により構成さ
れ、波長に比べて十分小さい開口寸法を有する空胴を配
列したハニカム構造体１において、その空胴の内壁を高
透磁率材２で覆ったものである。一空胴内の対向する面
の間隔，奥行きがともに1cmである電磁波遮へい体では
数百MHz以下の周波数帯で得られる最大の遮へい効果は
約42dBである。これは同一寸法を有する従来のハニカム
構造電磁波遮へい体に比べ、10dB大きくなっている。In the drawing, the present invention is a honeycomb structure 1 in which cavities formed of a good conductor such as metal and having an opening dimension sufficiently smaller than a wavelength are arranged, and the inner walls of the cavities are covered with a high magnetic permeability material 2. It is. The maximum shielding effect obtained in a frequency band of several hundred MHz or less is about 42 dB for an electromagnetic wave shielding body in which the spacing and the depth of the opposing surfaces in a cavity are both 1 cm. This is 10 dB larger than the conventional honeycomb structure electromagnetic wave shield having the same dimensions.
第２図は本発明による電磁波遮へい体を電子機器筐体
３の開口部に取付けた例である。遮へい体本来のもつ十
分な電磁波遮へい効果を得るためには導電性ガスケット
材４などを用いて筐体３との接触状態を良好にし、遮へ
い体取付け部からの電磁波の漏洩を極力抑制する必要が
ある。FIG. 2 shows an example in which an electromagnetic wave shielding body according to the present invention is attached to an opening of an electronic device housing 3. In order to obtain a sufficient electromagnetic wave shielding effect inherent in the shield, it is necessary to improve the contact state with the housing 3 by using a conductive gasket material 4 or the like, and to minimize leakage of the electromagnetic wave from the mounting portion of the shield. is there.
以上説明したように本発明はハニカム構造の空胴壁面
を高透磁率材で覆うことにより、同一寸法でより大きな
電磁波透過減衰量を得ることができる。したがって、放
熱や換気のための十分な開口面積を維持したまま電磁波
遮へい性能を向上する効果がある。As described above, in the present invention, by covering the cavity wall surface of the honeycomb structure with the high magnetic permeability material, a larger electromagnetic wave transmission attenuation can be obtained with the same dimensions. Therefore, there is an effect of improving the electromagnetic wave shielding performance while maintaining a sufficient opening area for heat radiation and ventilation.
第１図は本発明による電磁波遮へい体を示す斜視図、第
２図は本発明に係る電磁波遮へい体を電子機器筐体に実
装した状態を示す図、第３図（ａ），（ｂ）は従来の開
口面が矩形になる空胴を多数配列した構造体、及びハニ
カム構造体による電磁波遮へい体を示す斜視図である。 １……ハニカム構造体、２……高透磁率材 ３……電子機器筐体、４……導電性ガスケット材FIG. 1 is a perspective view showing an electromagnetic wave shielding body according to the present invention, FIG. 2 is a view showing a state where the electromagnetic wave shielding body according to the present invention is mounted on an electronic device housing, and FIGS. FIG. 5 is a perspective view showing a conventional structure in which a large number of cavities having a rectangular opening surface are arranged, and an electromagnetic wave shield formed by a honeycomb structure. DESCRIPTION OF SYMBOLS 1 ... Honeycomb structure, 2 ... High magnetic permeability material 3 ... Electronic device housing, 4 ... Conductive gasket material
Claims (1)
法が波長に比べ十分小さく、断面形状が六角形の空胴を
多数並べたハニカム構造体において、前記空胴の壁面を
高透磁率材料にて被覆したことを特徴とする電磁波遮へ
い体。1. A honeycomb structure comprising a number of cavities having a hexagonal cross section and having a cross-sectional dimension sufficiently smaller than a wavelength and made of a good conductor such as a metal, wherein the walls of the cavities are made of a material having a high magnetic permeability. An electromagnetic wave shielding body characterized in that it is coated with an electromagnetic wave.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP26987389A JP2737307B2 (en) | 1989-10-17 | 1989-10-17 | Electromagnetic shielding |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP26987389A JP2737307B2 (en) | 1989-10-17 | 1989-10-17 | Electromagnetic shielding |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH03131092A JPH03131092A (en) | 1991-06-04 |
| JP2737307B2 true JP2737307B2 (en) | 1998-04-08 |
Family
ID=17478400
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP26987389A Expired - Lifetime JP2737307B2 (en) | 1989-10-17 | 1989-10-17 | Electromagnetic shielding |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2737307B2 (en) |
Families Citing this family (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE69632422T2 (en) | 1995-08-11 | 2005-05-19 | Zenon Environmental Inc., Oakville | Process for embedding hollow fiber membranes |
| US5895885A (en) * | 1997-03-20 | 1999-04-20 | Kunkel; George M. | Air vent for electromagnetic shielding |
| US5910639A (en) * | 1997-03-20 | 1999-06-08 | Kunkel; George M. | Air vent panels for electromagnetic shielding |
| CN106255397A (en) * | 2015-06-04 | 2016-12-21 | 鸿富锦精密工业(武汉)有限公司 | Case of electronic device |
| CN106285374A (en) * | 2015-06-04 | 2017-01-04 | 无锡市鑫盾辐射防护器材有限公司 | A kind of seamless No leakage radiation-retarding door |
| WO2023204194A1 (en) * | 2022-04-18 | 2023-10-26 | Ｎｅｘｔ Ｉｎｎｏｖａｔｉｏｎ合同会社 | Electromagnetic wave blocking filter |
-
1989
- 1989-10-17 JP JP26987389A patent/JP2737307B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPH03131092A (en) | 1991-06-04 |
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