JPH06204684A - Magnetic shielding apparatus - Google Patents
Magnetic shielding apparatusInfo
- Publication number
- JPH06204684A JPH06204684A JP4060980A JP6098092A JPH06204684A JP H06204684 A JPH06204684 A JP H06204684A JP 4060980 A JP4060980 A JP 4060980A JP 6098092 A JP6098092 A JP 6098092A JP H06204684 A JPH06204684 A JP H06204684A
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- Prior art keywords
- magnetic field
- axis
- superconductor
- coil
- magnetic
- Prior art date
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- Shielding Devices Or Components To Electric Or Magnetic Fields (AREA)
- Manufacturing Of Electric Cables (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は例えば超電導体を用いた
磁気シールド装置に関し、極低磁場環境を得ることので
きる磁気シールド装置に関するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic shield device using, for example, a superconductor, and more particularly to a magnetic shield device capable of obtaining an extremely low magnetic field environment.
【０００２】[0002]
【従来の技術】従来、磁気シールド空間（磁気シールド
の対象となる空間）の外部磁場雑音を低減する技術とし
てアクティブシールドという考え方が存在していた。図
７はアクティブシールドの原理の概略を説明する説明図
である。図において、磁気シールド空間を取り囲む面
（８面）には、Ｘ軸コイル２Ｘａ，２Ｘｂ、Ｙ軸コイル
２Ｙａ，２Ｙｂ、Ｚ軸コイル２Ｚａ，２Ｚｂが配置され
ており、各軸のコイルには電流源４Ｘ，４Ｙ，４Ｚが接
続されている。2. Description of the Related Art Conventionally, the concept of active shield has existed as a technique for reducing external magnetic field noise in a magnetic shield space (a space that is the target of magnetic shield). FIG. 7 is an explanatory diagram for explaining the outline of the principle of the active shield. In the figure, X-axis coils 2Xa, 2Xb, Y-axis coils 2Ya, 2Yb, Z-axis coils 2Za, 2Zb are arranged on the surface (8 surfaces) surrounding the magnetic shield space, and a current source is provided for each axis coil. 4X, 4Y and 4Z are connected.
【０００３】また、磁気シールド空間の略中央部には、
Ｘ，Ｙ，Ｚの各方向の磁束を検出するための磁束計３
Ｘ，３Ｙ，３Ｚが配置されており、各軸コイルの電流源
４Ｘ，４Ｙ，４Ｚと帰還増幅器５Ｘ，５Ｙ，５Ｚを介し
て接続されている。図のような磁気シールド装置は、磁
束計３Ｘ，３Ｙ，３Ｚで内部磁場を測定しながら各軸コ
イル２Ｘａ，２Ｘｂ，２Ｙａ，２Ｙｂ，２Ｚａ，２Ｚｂ
に電流を流し、外部からの雑音磁場を打ち消すような磁
場発生させ、低磁場空間を実現しようとするものであ
る。Further, in the substantially central portion of the magnetic shield space,
Magnetometer 3 for detecting magnetic flux in each direction of X, Y, Z
X, 3Y, 3Z are arranged and are connected to the current sources 4X, 4Y, 4Z of the respective axis coils via the feedback amplifiers 5X, 5Y, 5Z. The magnetic shield device as shown in the figure, while measuring the internal magnetic field with the magnetometers 3X, 3Y, 3Z, the respective axial coils 2Xa, 2Xb, 2Ya, 2Yb, 2Za, 2Zb.
A low magnetic field space is realized by applying a current to the magnetic field to generate a magnetic field that cancels the noise magnetic field from the outside.
【０００４】一方、超電導体を用いた磁気シールド装置
も従来から知られている。これは所定の空間を超電導材
料で形成された磁気シールド体で囲み、これを超電導材
料の臨界温度ＴC 以下に冷却することにより、超電導状
態に転移させてこのシールド体を反磁性体とすることに
より、外部からの磁束をこのシールド体外部に押し出し
て、極低磁場空間を得るものである。例えば、超電導材
料を円筒状に形成して用いると、地球磁場環境下で円筒
内部に極低磁場空間を形成できる。このような超電導材
料を用いた磁気シールド装置は、例えば人体から発生す
る磁場を検出して研究・診断を行なう生体磁場計測のた
めの磁気シールド装置として開発されている。On the other hand, a magnetic shield device using a superconductor has been conventionally known. This is to enclose a predetermined space with a magnetic shield body made of a superconducting material, and to cool it to a temperature below the critical temperature T C of the superconducting material to transform it into a superconducting state and make this shield body a diamagnetic body. Thus, the magnetic flux from the outside is pushed out of the shield body to obtain an extremely low magnetic field space. For example, when the superconducting material is formed into a cylindrical shape and used, an extremely low magnetic field space can be formed inside the cylinder under the earth's magnetic field environment. A magnetic shield device using such a superconducting material has been developed as a magnetic shield device for measuring a biomagnetic field, for example, by conducting a research / diagnosis by detecting a magnetic field generated from a human body.
【０００５】[0005]
【発明が解決しようとする課題】ところで、前述のよう
なシールド空間を囲む超電導材料の壁面からの磁場の染
みこみがない場合には、円筒内部磁場は円筒の開口部か
らの侵入量で決まり、その量は指数的に減衰するため、
例えば円筒の半径Ｒに対する開口からの深さｚがｚ／Ｒ
＝９の位置では約１０-7もの減衰率が得られる。By the way, when there is no soaking of the magnetic field from the wall surface of the superconducting material surrounding the shield space as described above, the magnetic field inside the cylinder is determined by the amount of penetration from the opening of the cylinder, Since its amount decays exponentially,
For example, the depth z from the opening with respect to the radius R of the cylinder is z / R
At the position of = 9, an attenuation rate of about 10 -7 can be obtained.
【０００６】しかしながら、超電導材料として酸化物超
電導体を用いると、超電導材料内の欠陥や粒界間から磁
場が染みこむため、円筒内部磁場はこの超電導体の壁面
からの磁場の染みこみ量と円筒の開口部からの侵入量の
和で決まることとなる。現状の酸化物超電導体の壁面か
らの磁場の染みこみ量は例えば外部磁場の約１０-5であ
り、生体磁気計測，特に脳磁界計測においては減衰率が
不充分であった。However, when an oxide superconductor is used as the superconducting material, the magnetic field permeates from defects or grain boundaries in the superconducting material. Will be determined by the sum of the amount of penetration from the opening. The amount of magnetic field soaked from the wall surface of the current oxide superconductor is, for example, about 10 −5 of the external magnetic field, and the attenuation rate was insufficient in biomagnetic measurement, particularly brain magnetic field measurement.
【０００７】本発明は、超電導体の壁面からの磁場の染
みこみ量を減少させ、例えば生体磁気計測に充分な遮蔽
率を得る磁気シールド装置を得ることを目的とする。It is an object of the present invention to provide a magnetic shield device which reduces the amount of magnetic field penetration from the wall surface of a superconductor and obtains a sufficient shielding rate for biomagnetic measurement, for example.
【０００８】[0008]
【課題を解決するための手段】本発明に係る磁気シール
ド装置では、超電導体が所定の磁気シールド空間を囲む
ように配置された磁気シールド装置において、少なくと
も１つの開口部を備えた前記シールド空間に外部から加
わる外部磁場を制御する磁場制御手段を備えたものであ
る。In the magnetic shield device according to the present invention, in a magnetic shield device in which a superconductor is arranged so as to surround a predetermined magnetic shield space, the shield space having at least one opening is provided. A magnetic field control means for controlling an external magnetic field applied from the outside is provided.
【０００９】具体的にこの磁場制御手段とは、前記所定
の磁気シールド空間内部の内部磁場を打ち消す磁場を前
記超電導体外部に形成させる所謂「アクティブシール
ド」手段であり、更に、互いに直交する３方向から加わ
る外部磁場を打ち消す磁場を制御するものである。尚、
本発明における前述の磁気シールド空間とは、具体的に
側方向を超電導材料で囲んだ筒状の磁気シールド体のよ
うに、１つ又は２つの開口部を備えたものを含む。Specifically, the magnetic field control means is a so-called "active shield" means for forming a magnetic field for canceling the internal magnetic field in the predetermined magnetic shield space outside the superconductor, and further, in three directions orthogonal to each other. It controls the magnetic field that cancels the external magnetic field applied from. still,
The above-mentioned magnetic shield space in the present invention specifically includes one having one or two openings, such as a cylindrical magnetic shield body whose lateral direction is surrounded by a superconducting material.
【００１０】[0010]
【作用】本発明においては、超電導体によって囲まれた
少なくとも１つの開口部を備えたシールド空間に外部か
ら加わる外部磁場を制御する磁場制御手段を備えたもの
であるため、超電導体に加わる磁場を弱めて、超電導体
の壁面からの磁場の染みこみ量を減少させる。In the present invention, since the shield space having at least one opening surrounded by the superconductor is provided with the magnetic field control means for controlling the external magnetic field applied from the outside, the magnetic field applied to the superconductor is controlled. It weakens and reduces the amount of field penetration from the wall of the superconductor.
【００１１】具体的には、少なくとも１つの開口部を備
えたシールド空間領域には超電導筒からの染みこんでく
る外部磁場と開口部から侵入する外部磁場とを減少させ
るため、磁場制御手段は互いに直交する３方向から加わ
る外部磁場を打ち消す磁場を発生する磁場制御手段であ
る。Specifically, in the shield space region having at least one opening, the external magnetic field infiltrating from the superconducting tube and the external magnetic field penetrating from the opening are reduced, so that the magnetic field control means mutually operate. It is a magnetic field control means for generating a magnetic field that cancels an external magnetic field applied from three orthogonal directions.
【００１２】即ち、超電導体の所定の場所に超電導体の
軸方向とそれに直交する方向との３方向の磁場を発生さ
せるコイルを設置するとともに、磁気センサを超電導体
内部のシールド空間に配置して磁場を検出し、この検出
結果に基づいてセンサを配置した箇所での磁場がゼロに
なるように、コイルで発生させる磁場を制御してやれば
良い。これにより、センサの配置位置より奥の広い空間
に渡って非常に低い磁場を実現できる。That is, a coil for generating a magnetic field in three directions of an axial direction of the superconductor and a direction orthogonal thereto is installed at a predetermined position of the superconductor, and a magnetic sensor is arranged in a shield space inside the superconductor. It suffices to detect the magnetic field and control the magnetic field generated by the coil based on the detection result so that the magnetic field at the location of the sensor becomes zero. This makes it possible to realize a very low magnetic field over a space deeper than the position where the sensor is arranged.
【００１３】例えば、超電導体製筒が両端に開口部を持
つ場合には、超電導体の壁面からの磁場の染みこみ量が
超電導体製筒の開口部からの侵入量を上回るシールド空
間領域の超電導体製筒に加わる磁場を弱くするように、
その超電導体製筒の領域付近に加わる外部磁場を打ち消
す磁場を発生する磁場制御手段を設置する。For example, in the case where the superconductor cylinder has openings at both ends, the amount of the magnetic field soaked from the wall surface of the superconductor exceeds the amount of penetration from the opening of the superconductor cylinder. To weaken the magnetic field applied to the body cylinder,
Magnetic field control means for generating a magnetic field for canceling the external magnetic field applied near the region of the superconductor cylinder is installed.
【００１４】また、超電導体製筒が一端に開口部、他端
に閉じられた部分を持つ場合には、その閉じられた部分
の付近に加わる外部磁場の打消し量は装置全体として必
要とする遮蔽度によるが、例えば脳磁界測定に使用する
場合には１／１００以上の打消し能力を持つことが望ま
しい。If the superconductor cylinder has an opening at one end and a closed portion at the other end, the amount of cancellation of the external magnetic field applied near the closed portion is required for the entire apparatus. Although it depends on the degree of shielding, it is desirable to have a canceling ability of 1/100 or more when used for measuring brain magnetic fields, for example.
【００１５】[0015]
【実施例】（実施例１）図１は本発明の磁気シールド装
置の一実施例の構成を示す説明図である。図１に示すよ
うに、両端に開口部を持つ半径３０ｍｍ×長さ６００ｍ
ｍの酸化物超電導体製円筒１１の中心付近に一辺が２０
０ｍｍの磁場キャンセル用３軸コイル１２を配置した。
３軸コイル１２で囲まれた酸化物超電導体製円筒１１の
中心には、フラックスゲート型磁束計１３が互いに直交
する方向の磁場を検出するようにＸ，Ｙ，Ｚの３軸分配
置されている。(Embodiment 1) FIG. 1 is an explanatory view showing the configuration of an embodiment of a magnetic shield device of the present invention. As shown in Fig. 1, a radius of 30 mm and a length of 600 m with openings at both ends
There are 20 sides on the side of the center of the oxide superconductor cylinder 11 of m.
A 0 mm magnetic field canceling triaxial coil 12 was arranged.
At the center of the oxide superconductor cylinder 11 surrounded by the triaxial coil 12, a fluxgate type magnetometer 13 is arranged for three axes of X, Y and Z so as to detect magnetic fields in directions orthogonal to each other. There is.
【００１６】磁場キャンセル用３軸コイル１２には、Ｘ
軸コイル，Ｙ軸コイル，Ｚ軸コイルの各々に供給する電
流源１４Ｘ，１４Ｙ，１４Ｚを備え、Ｘ軸，Ｙ軸，Ｚ軸
のフラックスゲート型磁束計１３の各々の出力端は帰還
増幅器１５Ｘ，１５Ｙ，１５Ｚを介して各軸の電流源１
４Ｘ，１４Ｙ，１４Ｚに接続されている。The three-axis coil 12 for magnetic field cancellation has an X
A current source 14X, 14Y, 14Z for supplying to each of the axial coil, the Y-axis coil, and the Z-axis coil is provided, and each output end of the X-axis, Y-axis, and Z-axis fluxgate type fluxmeter 13 has a feedback amplifier 15X, Current source 1 for each axis via 15Y and 15Z
It is connected to 4X, 14Y, and 14Z.
【００１７】以上のように、この磁場キャンセル用３軸
コイル１２により超電導体製円筒１１に対し、任意の方
向を向いている外部磁場を互いに直交する３軸の磁束計
１３で検知し、磁束計１３の３方向の検出出力がをゼロ
となるようにＸ軸，Ｙ軸，Ｚ軸の３軸コイル１２に流す
電流を軸ごとに制御し、外部磁場を打消す磁場を磁場キ
ャンセル用３軸コイル１２により発生させた。As described above, the magnetic field canceling triaxial coil 12 detects an external magnetic field directed in an arbitrary direction with respect to the superconductor cylinder 11 by the triaxial magnetometers 3 which are orthogonal to each other, and the magnetometer. The magnetic field for canceling the external magnetic field is controlled by controlling the currents flowing through the X-axis, Y-axis, and Z-axis triaxial coils 12 for each axis so that the detection outputs of the three directions of 13 are zero. Generated by 12.
【００１８】図２は図１の比較例の構成を示す説明図で
ある。図に示すように、図１と同様の両端に開口部を持
つ半径３０ｍｍ×長さ６００ｍｍの酸化物超電導体製円
筒２１を用いた。図１に示した磁気シールド装置と図２
に示した磁気シールド装置との内部磁場分布を比較し
た。FIG. 2 is an explanatory diagram showing the configuration of the comparative example of FIG. As shown in the figure, the same oxide superconductor cylinder 21 having a radius of 30 mm and a length of 600 mm having openings at both ends as in FIG. 1 was used. The magnetic shield device shown in FIG. 1 and FIG.
The internal magnetic field distribution was compared with the magnetic shield device shown in.
【００１９】図３は図１に示した磁気シールド装置の内
部磁場分布を示す線図であり、図４は図２に示した磁気
シールド装置の内部磁場分布を示す線図である。図にお
いて、縦軸は減衰率を、横軸は超電導体の半径Ｒに対す
る開口からの深さｚを示し、◇は軸方向成分、□は径方
向成分を示している。FIG. 3 is a diagram showing the internal magnetic field distribution of the magnetic shield device shown in FIG. 1, and FIG. 4 is a diagram showing the internal magnetic field distribution of the magnetic shield device shown in FIG. In the figure, the vertical axis represents the attenuation factor, the horizontal axis represents the depth z from the opening with respect to the radius R of the superconductor, ⋄ indicates the axial component, and □ indicates the radial component.
【００２０】図に示すように、比較例では、ｚ＞３・Ｒ
（軸方向成分），ｚ＞６・Ｒ（径方向成分）において超
電導体の壁面からの磁場の染みこみにより減衰率は１０
-5で飽和しているのに対し、実施例では、ｚ＞６・Ｒで
更に磁場が１／１００以上に減衰し、ｚ＝１０・Ｒの位
置で＜１０-7の減衰率が得られている。As shown in the figure, in the comparative example, z> 3.R
(Axial component), z> 6 · R (radial component), the attenuation factor is 10 due to the penetration of the magnetic field from the wall surface of the superconductor.
While saturated at −5 , in the example, the magnetic field was further attenuated by 1/100 or more at z> 6 · R, and an attenuation rate of <10 −7 was obtained at the position of z = 10 · R. ing.
【００２１】（実施例２）図５は本発明の磁気シールド
装置の他の実施例の構成を示す説明図である。図５に示
すように、一端に開口部、他端に閉じられた部分を持つ
半径３０ｍｍ×長さ３００ｍｍの酸化物超電導体製円筒
５１の、閉じられた部分の付近に一辺が２００ｍｍの磁
場キャンセル用３軸コイル５２を配置した。３軸コイル
５２でか囲まれた酸化物超電導体製円筒の内部には、フ
ラックスゲート型磁束計５３が互いに直交する方向の磁
場を検出するようにＸ，Ｙ，Ｚの３軸分配置されてい
る。(Embodiment 2) FIG. 5 is an explanatory view showing the configuration of another embodiment of the magnetic shield apparatus of the present invention. As shown in FIG. 5, in a cylinder 51 made of an oxide superconductor having a radius of 30 mm and a length of 300 mm, which has an opening portion at one end and a closed portion at the other end, a magnetic field cancellation with a side of 200 mm near the closed portion. A three-axis coil 52 for use is arranged. Inside the oxide superconductor cylinder surrounded by the triaxial coil 52, fluxgate type magnetometers 53 are arranged for three axes of X, Y and Z so as to detect magnetic fields in directions orthogonal to each other. There is.
【００２２】磁場キャンセル用３軸コイル５２には、Ｘ
軸コイル，Ｙ軸コイル，Ｚ軸コイルの各々に供給する電
流源５４Ｘ，５４Ｙ，５４Ｚを備え、Ｘ軸，Ｙ軸，Ｚ軸
のフラックスゲート型磁束計５３の各々の出力端は帰還
増幅器５５Ｘ，５５Ｙ，５５Ｚを介して各軸の電流源５
４Ｘ，５４Ｙ，５４Ｚに接続されている。The X-axis coil 52 for magnetic field cancellation has an X
A current source 54X, 54Y, 54Z is supplied to each of the axial coil, the Y-axis coil, and the Z-axis coil, and the output ends of the X-axis, Y-axis, and Z-axis fluxgate type magnetometers 53 are feedback amplifiers 55X, respectively. Current source 5 for each axis via 55Y and 55Z
It is connected to 4X, 54Y, and 54Z.
【００２３】以上のように、この磁場キャンセル用３軸
コイル５２により超電導体製円筒５１に対し、任意の方
向を向いている外部磁場を互いに直交する３軸の磁束計
５３で検知し、磁束計５３の３方向の検出出力がをゼロ
となるようにＸ軸，Ｙ軸，Ｚ軸の３軸コイル５２に流す
電流を軸ごとに制御し、外部磁場を打消す磁場を磁場キ
ャンセル用３軸コイル５２により発生させた。As described above, the magnetic field canceling triaxial coil 52 detects an external magnetic field oriented in any direction with respect to the superconductor cylinder 51 by the triaxial magnetometers 53 orthogonal to each other, and the magnetometer. The magnetic field for canceling the external magnetic field is controlled by controlling the current flowing through the X-axis, Y-axis, and Z-axis triaxial coils 52 for each axis so that the detection output of 53 in three directions becomes zero. 52.
【００２４】図６は図５の比較例の構成を示す説明図で
ある。図に示すように、図５と同様の両端に開口部を持
つ半径３０ｍｍ×長さ６００ｍｍの酸化物超電導体製円
筒６１を用いた。図５に示した磁気シールド装置と図２
に示した磁気シールド装置との内部磁場分布を比較した
ところ、前述の図３及び図４と同様になった。FIG. 6 is an explanatory diagram showing the configuration of the comparative example of FIG. As shown in the figure, an oxide superconductor cylinder 61 having a radius of 30 mm and a length of 600 mm having openings at both ends as in the case of FIG. 5 was used. The magnetic shield device shown in FIG. 5 and FIG.
When the internal magnetic field distribution is compared with the magnetic shield device shown in FIG. 3, the results are the same as those in FIGS.
【００２５】[0025]
【発明の効果】本発明は以上説明したとおり、超電導体
によって囲まれた少なくとも１つの開口部を備えたシー
ルド空間に外部から加わる外部磁場を制御する磁場制御
手段を備えたものであるため、超電導体に加わる磁場を
弱めて、超電導体の壁面からの磁場の染みこみ量を減少
させ、例えば生体磁気計測に充分な遮蔽率を得ることが
できるという効果がある。As described above, the present invention is provided with the magnetic field control means for controlling the external magnetic field applied from the outside to the shield space having at least one opening surrounded by the superconductor. There is an effect that the magnetic field applied to the body is weakened to reduce the amount of the magnetic field soaked from the wall surface of the superconductor, and for example, a sufficient shielding rate can be obtained for biomagnetic measurement.
【００２６】具体的には、少なくとも１つの開口部を備
えたシールド空間領域には超電導体製筒からの染みこん
でくる外部磁場と開口部から侵入する外部磁場とを減少
させるため、磁場制御手段は互いに直交する３方向から
加わる外部磁場を打ち消す磁場を発生する磁場制御手段
である。Specifically, the magnetic field control means is provided to reduce the external magnetic field infiltrated from the superconductor cylinder and the external magnetic field penetrating from the opening in the shield space area having at least one opening. Is a magnetic field control means for generating a magnetic field that cancels external magnetic fields applied from three directions orthogonal to each other.
【図１】本発明の磁気シールド装置の一実施例の構成を
示す説明図である。FIG. 1 is an explanatory diagram showing a configuration of an embodiment of a magnetic shield device of the present invention.
【図２】図１の比較例の構成を示す説明図である。FIG. 2 is an explanatory diagram showing a configuration of a comparative example of FIG.
【図３】図１に示した磁気シールド装置の内部磁場分布
を示す線図である。FIG. 3 is a diagram showing an internal magnetic field distribution of the magnetic shield device shown in FIG. 1.
【図４】図２に示した磁気シールド装置の内部磁場分布
を示す線図である。FIG. 4 is a diagram showing an internal magnetic field distribution of the magnetic shield device shown in FIG.
【図５】本発明の磁気シールド装置の他の実施例の構成
を示す説明図である。FIG. 5 is an explanatory diagram showing the configuration of another embodiment of the magnetic shield apparatus of the present invention.
【図６】図５の比較例の構成を示す説明図である。6 is an explanatory diagram showing a configuration of a comparative example of FIG.
【図７】アクティブシールドの原理の概略を説明する説
明図である。FIG. 7 is an explanatory diagram illustrating the outline of the principle of the active shield.
【符号の説明】 １１，２１，５１，６１ …酸化物超電導体製円筒 １２， ５２ …磁場キャンセル用３軸コイ
ル １３， ５３， …フラックスゲート型磁束計 １４Ｘ〜Ｚ，５４Ｘ〜Ｚ …電流源 １５Ｘ〜Ｚ，５５Ｘ〜Ｚ …帰還増幅器[Explanation of reference numerals] 11, 21, 51, 61 ... Oxide superconductor cylinder 12, 52 ... Triaxial magnetic field canceling coil 13, 53, ... Fluxgate type magnetometer 14X to Z, 54X to Z ... Current source 15X ~ Z, 55X ~ Z ... Feedback amplifier
Claims (1)
むように配置された磁気シールド装置において、 少なくとも１つの開口部を備えた前記シールド空間に外
部から加わる外部磁場を制御する磁場制御手段を備えた
ことを特徴とする磁気シールド装置。1. A magnetic shield device in which a superconductor is arranged so as to surround a predetermined magnetic shield space, comprising magnetic field control means for controlling an external magnetic field externally applied to the shield space having at least one opening. A magnetic shield device characterized in that
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP4060980A JPH06204684A (en) | 1992-02-18 | 1992-02-18 | Magnetic shielding apparatus |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP4060980A JPH06204684A (en) | 1992-02-18 | 1992-02-18 | Magnetic shielding apparatus |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH06204684A true JPH06204684A (en) | 1994-07-22 |
Family
ID=13158090
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP4060980A Pending JPH06204684A (en) | 1992-02-18 | 1992-02-18 | Magnetic shielding apparatus |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH06204684A (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0832273A (en) * | 1994-07-19 | 1996-02-02 | Chodendo Sensor Kenkyusho:Kk | Magnetic shield |
| JPH09243606A (en) * | 1996-03-08 | 1997-09-19 | Kawasaki Heavy Ind Ltd | Probe device |
| JP2014008155A (en) * | 2012-06-28 | 2014-01-20 | Kyushu Univ | Separation type magnetic shield device |
| CN111554470A (en) * | 2020-05-15 | 2020-08-18 | 北京北方华创微电子装备有限公司 | Degaussing device and semiconductor processing equipment |
-
1992
- 1992-02-18 JP JP4060980A patent/JPH06204684A/en active Pending
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0832273A (en) * | 1994-07-19 | 1996-02-02 | Chodendo Sensor Kenkyusho:Kk | Magnetic shield |
| JPH09243606A (en) * | 1996-03-08 | 1997-09-19 | Kawasaki Heavy Ind Ltd | Probe device |
| JP2014008155A (en) * | 2012-06-28 | 2014-01-20 | Kyushu Univ | Separation type magnetic shield device |
| CN111554470A (en) * | 2020-05-15 | 2020-08-18 | 北京北方华创微电子装备有限公司 | Degaussing device and semiconductor processing equipment |
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