JPH0464282A - Shielding case - Google Patents
Shielding caseInfo
- Publication number
- JPH0464282A JPH0464282A JP17803590A JP17803590A JPH0464282A JP H0464282 A JPH0464282 A JP H0464282A JP 17803590 A JP17803590 A JP 17803590A JP 17803590 A JP17803590 A JP 17803590A JP H0464282 A JPH0464282 A JP H0464282A
- Authority
- JP
- Japan
- Prior art keywords
- case
- frequency
- shielding effect
- magnetic
- magnetic field
- 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.)
- Pending
Links
- 230000035699 permeability Effects 0.000 claims abstract description 10
- 238000010030 laminating Methods 0.000 claims abstract description 4
- 239000003973 paint Substances 0.000 claims abstract description 4
- 229910052751 metal Inorganic materials 0.000 claims description 13
- 239000002184 metal Substances 0.000 claims description 13
- 239000000853 adhesive Substances 0.000 claims description 2
- 230000001070 adhesive effect Effects 0.000 claims description 2
- 230000000694 effects Effects 0.000 abstract description 15
- 230000005672 electromagnetic field Effects 0.000 abstract description 9
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 abstract description 7
- 229910052802 copper Inorganic materials 0.000 abstract description 7
- 239000010949 copper Substances 0.000 abstract description 7
- 229910000889 permalloy Inorganic materials 0.000 abstract description 5
- 239000000463 material Substances 0.000 abstract description 3
- 238000007747 plating Methods 0.000 abstract description 3
- 238000000151 deposition Methods 0.000 abstract 2
- 239000000126 substance Substances 0.000 abstract 1
- 239000000696 magnetic material Substances 0.000 description 5
- 230000005389 magnetism Effects 0.000 description 5
- 229910052782 aluminium Inorganic materials 0.000 description 3
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 3
- 230000000903 blocking effect Effects 0.000 description 3
- 230000001133 acceleration Effects 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 230000010355 oscillation Effects 0.000 description 2
- 239000011347 resin Substances 0.000 description 2
- 229920005989 resin Polymers 0.000 description 2
- BQCADISMDOOEFD-UHFFFAOYSA-N Silver Chemical compound [Ag] BQCADISMDOOEFD-UHFFFAOYSA-N 0.000 description 1
- 229910000831 Steel Inorganic materials 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 239000004020 conductor Substances 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 239000013013 elastic material Substances 0.000 description 1
- 230000005684 electric field Effects 0.000 description 1
- 239000003292 glue Substances 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- 229910052709 silver Inorganic materials 0.000 description 1
- 239000004332 silver Substances 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
- 238000007740 vapor deposition Methods 0.000 description 1
Landscapes
- Laminated Bodies (AREA)
- Shielding Devices Or Components To Electric Or Magnetic Fields (AREA)
Abstract
Description
【発明の詳細な説明】
（産業上の利用分野）
本発明は通信機器等の電子装置、特に高周波コイルに使
用するシールドケースに関し、詳細には直流から高周波
に至る広範囲に亙って電界及び磁気両者の遮蔽を可能と
したシールドケースに関する。Detailed Description of the Invention (Field of Industrial Application) The present invention relates to a shield case used for electronic devices such as communication equipment, especially high frequency coils. This invention relates to a shield case that can shield both.
（従来技術）
無線通信機をはじめとして高周波コイルを使用する電子
装置に於いては、該コイルに対する外部電磁界の影響を
排除し、またはコイルから発生する電磁界の近隣部品に
対する影響を排除するためにコイルを金属ケースにて覆
うようにしている。(Prior art) In electronic devices that use high-frequency coils, such as wireless communication devices, it is necessary to eliminate the influence of external electromagnetic fields on the coils, or to eliminate the influence of the electromagnetic fields generated from the coils on neighboring components. The coil is covered with a metal case.
例えば、無線機に多用されるＰＬＬ型シンセサイザの電
圧制御発振回路（ＶＣＯ）には一般に比較的大きいイン
ダクタンスとしてソレノイドコイルが使用されるが、従
来から銅やアルミ等の良導電性金属ケースで覆う構成を
とっていた。For example, a solenoid coil is generally used as a relatively large inductance in the voltage controlled oscillator circuit (VCO) of a PLL synthesizer that is often used in radio equipment, but it has traditionally been covered with a case made of a highly conductive metal such as copper or aluminum. was taking.
この理由は、コイルに流れる高周波電流によって発生す
る電磁界が近隣の他の回路パターン又は回路部品に作用
してノイズの発生成は膠動作の原因になることを防止す
るため及び、逆に近隣の回路部品や回路パターンに発生
する高周波磁界の影響によって前記■ＣＯの出力にノイ
ズが発生することを防止するためである。The reason for this is to prevent the electromagnetic field generated by the high-frequency current flowing through the coil from acting on other nearby circuit patterns or circuit components, causing noise generation and glue operation, and conversely, This is to prevent noise from being generated in the output of the CO due to the influence of high frequency magnetic fields generated in circuit components and circuit patterns.
しかしながら、従来から上述したように高周波コイルを
銅やアルミ等の導電性金属ケースで覆ったたけでは機器
に振動が加わった場合や移動しながらの使用時に僅かで
はあるがノイズが発生することが知られていた。However, as mentioned above, it has been known that simply covering a high frequency coil with a conductive metal case such as copper or aluminum can generate a small amount of noise when vibration is applied to the device or when the device is used while moving. was.
このノイズを除去するために、従来から当該コイルを収
納したシールドケース内に樹脂を充填して完全に固定し
、或は前記樹脂に代えてゲル状弾性体物質を充填し外部
からの振動を吸収するような手段が講じられていたが、
ノイズの発生を完全に除去することは不可能であった。In order to eliminate this noise, conventionally, the shield case that houses the coil is filled with resin to completely fix it, or instead of the resin, it is filled with a gel-like elastic material to absorb vibrations from the outside. Although measures were taken to
It has been impossible to completely eliminate noise generation.
（発明の目的）
本発明は上述した事情に鑑みて成されたものであって、
高周波電磁界から低周波磁界、更には直流磁界の全てに
互って遮蔽効果を有し、例えば高周波コイルを使用した
回路に発生するノイズを完全に除去することのできるシ
ールドケースを提供することを目的とする。(Object of the invention) The present invention has been made in view of the above-mentioned circumstances, and includes:
To provide a shielding case that has a mutually shielding effect from high frequency electromagnetic fields, low frequency magnetic fields, and even direct current magnetic fields, and can completely eliminate noise generated in a circuit using a high frequency coil, for example. purpose.
（発明の概要）
本発明では上記目的を達成するために以下の如き手段を
講する。(Summary of the Invention) The present invention takes the following measures to achieve the above object.
即ち、これら高周波用コイルを覆うケースとして、高透
磁率部材と高導電率部材とを少なくとも二層に積層して
シールドケースを構成、することを基本的考え方として
、その実施にあたっては高透磁率部材表面に高導電率金
属をメッキ又は蒸着するか、或はは高透磁率部材又は高
導電率部材のいずれか一方を接着剤又は塗料に混入して
他方部材に塗布した構成とする。In other words, the basic idea is to construct a shield case by laminating at least two layers of a high magnetic permeability member and a high conductivity member as a case to cover these high frequency coils, and in implementing this, high magnetic permeability members are used. The surface is plated or vapor-deposited with a highly conductive metal, or either a high magnetic permeability member or a high conductivity member is mixed with an adhesive or paint and applied to the other member.
（実施例）
以下、図示した実施例に基づいて本発明の詳細な説明す
るが、それに先立って上述した様に高周波コイルに振動
が加わった場合に、何故にノイズが発生するかについて
考察する。(Example) The present invention will be described in detail below based on the illustrated example, but first, as described above, when vibration is applied to the high frequency coil, why noise is generated will be considered.
実験によれば、ＦＭ変調機能を有するＰＬＬシンセサイ
ザのｖＣＯ用高同高周波コイル来通り良導電金属（高導
電率部材）のケースに収納した上、変調信号周波数１
ｋＨｚ、周波数偏移±１．３５ｋＨｚのＦＭ変調を加え
た状態で所定振幅の振動を種々周波数を変えて与え、当
該シンセサイザの発振出力をＦＭ検波することによって
ＦＭ性雑音の大きさを測定したところ、コイルに加わる
加速度が大きくなる程雑音レベルが大きくなった。According to experiments, the high frequency coil for vCO of a PLL synthesizer with FM modulation function was housed in a case made of a highly conductive metal (high conductivity material), and the modulation signal frequency was 1.
The magnitude of FM noise was measured by applying vibrations of a predetermined amplitude at various frequencies with FM modulation of kHz, frequency deviation ±1.35kHz, and performing FM detection on the oscillation output of the synthesizer. , the noise level increased as the acceleration applied to the coil increased.
この原因が上述した如く、該コイルとその近隣回路との
相互影響であるか否かを確認するためコイルのみを所要
距離能して装着したが、その離間距離によっては殆ど改
善は見られなかった。As mentioned above, in order to confirm whether the cause of this was due to mutual influence between the coil and its neighboring circuits, only the coil was installed at the required distance, but almost no improvement was observed depending on the distance. .
この事実から、高周波コイルに雑音を発生させる原因が
例えば地磁気等のような直流磁界或は送電線等から発生
する低周波磁界ではないかと考え以下に示すようなシー
ルドケースを作成し実験を行ったところ、極めて良好な
結果を得た。Based on this fact, we thought that the cause of the noise in the high-frequency coil was a direct current magnetic field such as the earth's magnetism, or a low-frequency magnetic field generated from power transmission lines, etc., so we created a shield case as shown below and conducted an experiment. However, very good results were obtained.
即ち、第１図ａ、ｂは本発明に係るシールドケースの一
実施例を示す側面断面図であり、ａは高透磁率部材のパ
ーマロイにて作ったケース１の外周表面に銅膜２をメッ
キ又は蒸着したシールドケースで、ｂはパーマロイケー
ス１の外周と内面の両面に銅膜２のメッキを施したもの
である。That is, FIGS. 1a and 1b are side cross-sectional views showing an embodiment of the shield case according to the present invention, and FIG. Alternatively, b is a vapor-deposited shield case in which both the outer periphery and inner surface of the permalloy case 1 are plated with a copper film 2.
面、上記鋼はメッキ、蒸着に限らずその他の手段でもよ
く、例えば導電塗料を塗布したものでもよい。また、密
閉容器を作る手段は種々あって、上記実施例の様に下端
部を上下二分割した構造の他、ケース天井板を分離して
蓋を被せる構造であってもよい。更には、ケースの形状
も方形に限る必要はなく遮蔽すべき部品等の形状に合わ
せて適宜決定すればよい。その際、必ずしも全方向を覆
う必要はな（、場合によっては底面が必要ないばあいか
あろう。The above-mentioned steel is not limited to plating or vapor deposition, and may be coated with conductive paint, for example. There are various means for making a sealed container, and in addition to the structure in which the lower end is divided into upper and lower halves as in the above embodiment, a structure in which the case ceiling plate is separated and covered with a lid may also be used. Further, the shape of the case need not be limited to a rectangular shape, and may be appropriately determined according to the shape of the parts to be shielded. In that case, it is not necessarily necessary to cover all directions (in some cases, the bottom may not be necessary).
第２図はこのシールドケースをＰ Ｌ、 Ｌシンセサイ
ザのＶＣＯ中のコイルに被せ、上述した実験と同じ測定
を行った結果を示したもので、縦軸には振動を加えない
ときの復調信号レベルをＯｄＢとしたときの雑音レベル
、横軸には振動による加速度（ｇ）をとったものであり
、この図には従来のシールドケースを使用した場合の結
果も同時に記載した。Figure 2 shows the results of the same measurements as in the experiment described above with this shield case placed over the coil in the VCO of the P L, L synthesizer. The vertical axis shows the demodulated signal level when no vibration is applied. The noise level is expressed as OdB, and the horizontal axis shows the acceleration (g) due to vibration. This figure also shows the results when a conventional shield case is used.
この図から明らかなように、本発明のシールドケースに
よれば従来のものに比べ大幅にノイズ低減効果が得られ
る。As is clear from this figure, the shield case of the present invention can significantly reduce noise compared to the conventional case.
このような効果が得られる理由は、次のように考えれば
理解できよう。The reason why such an effect can be obtained can be understood by considering the following.
即ち、高周波コイルに振動が加わると地磁気に対して相
対的にコイルが変移する結果、当該コイルに他磁を遮っ
て偏移する割合に対応して起電力が発生し発振出力中に
雑音が混入するものであろう。In other words, when vibration is applied to a high-frequency coil, the coil shifts relative to the earth's magnetism, and as a result, an electromotive force is generated corresponding to the rate at which the coil shifts by blocking other magnetism, and noise is mixed into the oscillation output. It would be something to do.
そこで、第１図に示したように高磁性体のパマロイのケ
ースであれば直流磁界及び低周波磁界に対して十分な遮
蔽効果があり、地磁気を遮蔽する結果、雑音の混入を防
止することができる。Therefore, as shown in Figure 1, the case of Pamalloy, which is a highly magnetic material, has a sufficient shielding effect against DC magnetic fields and low-frequency magnetic fields, and as a result of shielding geomagnetism, it is possible to prevent noise from entering. can.
従来は高周波コイルから発生する高周波電磁界のみを遮
蔽すれば足りるとして上述したように高導電率の金属ケ
ースによって遮蔽しており、このシールドケースでは対
象とする電磁界の周波数が一定以上高い場合は一応の効
果はあったが周波数が低くなると磁気遮蔽効果は著しく
低下して、極端な場合直流磁界に対しては全く遮蔽効果
が期待できなかった。Conventionally, it was sufficient to shield only the high-frequency electromagnetic field generated by the high-frequency coil, and as mentioned above, it was shielded with a high-conductivity metal case. Although it was somewhat effective, as the frequency became lower, the magnetic shielding effect decreased significantly, and in extreme cases, no shielding effect could be expected at all against DC magnetic fields.
この理由は明らかで、高い導電率金属板に入射する高周
波磁界に対しては渦電流が発生し、該渦電流によって新
たな磁界が発生するがその向きが前記入射する磁界と逆
向きとなって、結果的に磁界の通過を阻止することにな
る。The reason for this is clear: eddy currents are generated in response to high-frequency magnetic fields incident on a high-conductivity metal plate, and the eddy currents generate a new magnetic field, but the direction of the new magnetic field is opposite to that of the incident magnetic field. As a result, the passage of the magnetic field is blocked.
このとき前記磁界を阻止する逆磁界の大きさは、その電
流値は通過する磁界の変化量に比例し、従って、周波数
が高くなる程前記磁界阻止力は大きくなるが、周波数が
低くなると阻止力は低下するため上述したような地磁気
や低周ｊ＆ ＥＲ界に対してはシールド効果を呈しない
。At this time, the magnitude of the reverse magnetic field that blocks the magnetic field is proportional to the amount of change in the passing magnetic field. Therefore, the higher the frequency, the larger the magnetic field blocking force becomes, but the lower the frequency, the blocking force increases. Since the magnetic field decreases, it does not exhibit a shielding effect against the earth's magnetism and the low-frequency J&ER field as described above.
これに対し、パーマロイの如く高磁性体では、一般に導
電率が低く高周波磁界及び高周波電界に対しては遮蔽効
果はないものの、低周波磁界及び直流磁界に対しては磁
界が伝達し易い磁路となるから、磁力線は当該高磁性体
に集中し、該磁路を経て他方磁極方向に通過するから外
部からの磁界は高磁性体ケース内部に侵入せず、また内
部にて発生する磁界は外部に出力しない。その結果、上
記実験結果の如＜ ＶＣＯに作用する地磁気等の低周波
および直流磁界の影響が除去されてノイズの発生が大幅
に減少する。On the other hand, highly magnetic materials such as permalloy generally have low conductivity and do not have a shielding effect against high-frequency magnetic fields and high-frequency electric fields, but they form magnetic paths that allow magnetic fields to easily transmit low-frequency magnetic fields and DC magnetic fields. Therefore, the lines of magnetic force are concentrated on the highly magnetic material and pass through the magnetic path toward the other magnetic pole, so the magnetic field from the outside does not penetrate into the highly magnetic material case, and the magnetic field generated inside is not transmitted to the outside. No output. As a result, as shown in the above experimental results, the influence of low frequency waves such as terrestrial magnetism and direct current magnetic fields acting on the VCO is removed, and the generation of noise is significantly reduced.
第２図には第１図すのシールドケースな使用した場合都
、更に同シールドケースを二重に使用した場合について
実験したが、二重シールドの方がより効果が大きい。Fig. 2 shows the case where the shield case shown in Fig. 1 is used, and the case where the same shield case is used twice is also tested, and the double shield is more effective.
本発明は以上説明したように高磁性体と良導電体を共に
積層したので、高周波電磁界と低周波電磁界、更には直
流磁界の全てにってシールド効果を持たせることが可能
となる。In the present invention, as described above, since a highly magnetic material and a good conductor are laminated together, it is possible to provide a shielding effect against all of high frequency electromagnetic fields, low frequency electromagnetic fields, and even direct current magnetic fields.
本発明の実施にあたっては、パーマロイ等の高磁性体ケ
ースの表面をアルミ、銀、銅等の良導電性金属でメッキ
し、又はこれらの金属を蒸着すればよく、この際前記高
磁性体ケースの厚みを比較的大きくすればより効果的で
あろう。In implementing the present invention, the surface of a highly magnetic case such as permalloy may be plated with a highly conductive metal such as aluminum, silver, or copper, or these metals may be vapor-deposited. It would be more effective if the thickness was made relatively large.
（効果）
本発明は以上説明したように、高透磁率物体と高導電率
金属とを積層したものであるから、高周波電磁界につい
ては高導電率金属によって、また低周波並びに直流磁界
に関しては高透磁率物質が夫々電磁遮蔽効果を呈するの
で、全ての周波数に対する遮蔽効果をもったシールドケ
ースを実現する上で効果がある。特に、上記ＶＣＯに使
用するコイル等のように、外部磁界の影響によってノイ
ズを発生する部品に対するシールドケースとして最適で
ある。(Effects) As explained above, since the present invention is made by laminating a high magnetic permeability object and a high conductivity metal, high frequency electromagnetic fields are handled by the high conductivity metal, and low frequency and DC magnetic fields are handled by the high conductivity metal. Since each magnetically permeable material exhibits an electromagnetic shielding effect, it is effective in realizing a shielding case that has a shielding effect for all frequencies. In particular, it is ideal as a shielding case for components that generate noise due to the influence of external magnetic fields, such as the coils used in the VCO.
第１区ａ、ｂは本発明の一実施例を示すシールドケース
の断面構造図、第２図は本発明の効果を確認した実験結
果を示す特性図である。
１．１・・・パーマロイケース、
２．２・・・銅膜。Section 1 a and b are cross-sectional structural diagrams of a shield case showing one embodiment of the present invention, and FIG. 2 is a characteristic diagram showing experimental results confirming the effects of the present invention. 1.1... Permalloy case, 2.2... Copper film.
Claims (3)
したことを特徴とするシールドケース。(1) A shield case characterized by laminating two or more layers of a high magnetic permeability member and a high conductivity member.
着したことを特徴とするシールドケース。(2) A shield case characterized in that a high conductivity metal is plated or vapor-deposited on the surface of a high magnetic permeability member.
方が、接着剤又は塗料として他方部材に塗布されたもの
であることを特徴とする特許請求の範囲１項記載のシー
ルドケース。(3) The shield case according to claim 1, wherein either the high magnetic permeability member or the high conductivity member is applied to the other member as an adhesive or paint.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP17803590A JPH0464282A (en) | 1990-07-04 | 1990-07-04 | Shielding case |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP17803590A JPH0464282A (en) | 1990-07-04 | 1990-07-04 | Shielding case |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH0464282A true JPH0464282A (en) | 1992-02-28 |
Family
ID=16041449
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP17803590A Pending JPH0464282A (en) | 1990-07-04 | 1990-07-04 | Shielding case |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0464282A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH08167787A (en) * | 1994-12-13 | 1996-06-25 | Mitsubishi Materials Corp | Electromagnetic shielding material |
| JP2007278663A (en) * | 2006-04-11 | 2007-10-25 | Fuji Electric Holdings Co Ltd | Vibration type compressor |
| JP2018022744A (en) * | 2016-08-02 | 2018-02-08 | 株式会社デンソー | Electronic device |
-
1990
- 1990-07-04 JP JP17803590A patent/JPH0464282A/en active Pending
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH08167787A (en) * | 1994-12-13 | 1996-06-25 | Mitsubishi Materials Corp | Electromagnetic shielding material |
| JP2007278663A (en) * | 2006-04-11 | 2007-10-25 | Fuji Electric Holdings Co Ltd | Vibration type compressor |
| JP2018022744A (en) * | 2016-08-02 | 2018-02-08 | 株式会社デンソー | Electronic device |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US7642618B2 (en) | Semiconductor devices with inductors | |
| US4491843A (en) | Portable receiver with housing serving as a dipole antenna | |
| US10468354B2 (en) | Semiconductor device with magnetic layer and nonmagnetic layer | |
| EP0574813B1 (en) | Cavity resonator for an electron spin resonance device | |
| JPH0464282A (en) | Shielding case | |
| US3898565A (en) | Magnetic wave communication system | |
| US5303915A (en) | Tennis ball to line location | |
| JPH0946080A (en) | Shielding of electronic equipment | |
| US2442310A (en) | Directional antenna system | |
| JPWO2019003722A1 (en) | Balun | |
| JP3611048B2 (en) | High frequency inductor core | |
| JPS63275201A (en) | Magnetostatic device | |
| WO2002043135A1 (en) | Semiconductor device and its manufacturing method | |
| JP5148411B2 (en) | Piezoelectric device | |
| JPH1049287A (en) | Tablet of position detecting device | |
| JP2629622B2 (en) | Current probe | |
| JPH05235582A (en) | Magnetic shielding material | |
| JPH0236320Y2 (en) | ||
| JP2667523B2 (en) | Microwave equipment | |
| JPS6130273Y2 (en) | ||
| JPS62151007A (en) | Tuner | |
| RU2169428C2 (en) | Frequency mixer | |
| JPS6125239Y2 (en) | ||
| JPS6130272Y2 (en) | ||
| JPS62115812A (en) | Shielded device |