JPH05203711A - Cryogenic container for skid sensor - Google Patents
Cryogenic container for skid sensorInfo
- Publication number
- JPH05203711A JPH05203711A JP3328617A JP32861791A JPH05203711A JP H05203711 A JPH05203711 A JP H05203711A JP 3328617 A JP3328617 A JP 3328617A JP 32861791 A JP32861791 A JP 32861791A JP H05203711 A JPH05203711 A JP H05203711A
- Authority
- JP
- Japan
- Prior art keywords
- cryogenic container
- magnetic
- skid sensor
- frp
- outer layer
- 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.)
- Granted
Links
Landscapes
- Measuring Magnetic Variables (AREA)
- Packging For Living Organisms, Food Or Medicinal Products That Are Sensitive To Environmental Conditiond (AREA)
- Packaging Of Annular Or Rod-Shaped Articles, Wearing Apparel, Cassettes, Or The Like (AREA)
- Containers, Films, And Cooling For Superconductive Devices (AREA)
Abstract
(57)【要約】
【目的】 外来の高周波ノイズをシールドし、且つ渦電
流による磁気ノイズの少ないスキッドセンサー用極低温
容器を得る。
【構成】 内層３、外層２の二重構造からなり、内層３
内に液体ヘリウム５が注入され、スキッドセンサー６が
収納されるスキッドセンサー用極低温容器の、外層２を
非磁性で導電性のＦＲＰで形成し、内層３を非磁性で非
導電性のＦＲＰで形成するようにした。
(57) [Summary] [Purpose] To obtain a cryogenic container for a skid sensor that shields external high frequency noise and has little magnetic noise due to eddy currents. [Structure] The inner layer 3 and the outer layer 2 have a double structure, and the inner layer 3
In the cryogenic container for a skid sensor in which the liquid helium 5 is injected and the skid sensor 6 is housed, the outer layer 2 is made of a non-magnetic and conductive FRP, and the inner layer 3 is made of a non-magnetic and non-conductive FRP. To form.
Description
【０００１】[0001]
【産業上の利用分野】この発明は微弱な磁気を検出する
スキッド（ＳＱＵＩＤ）センサー用極低温容器に関する
ものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cryogenic container for a SQUID sensor for detecting weak magnetism.
【０００２】[0002]
【従来の技術】例えば、生体から発生される磁界などは
非常に小さく１０-10〜１０-13Ｔ程度であり、このよう
な微弱な磁気を検出するにはスキッドのような高感度な
センサーが必要不可欠である。しかしながらスキッドセ
ンサーはマイクロ波センサーでもあることから電磁干渉
を受けやすく、外部磁気ノイズはもちろんのこと放送
波、通信電波による電波ノイズもシールドされた環境下
で使用されなければならない。2. Description of the Related Art For example, a magnetic field generated from a living body is very small and is about 10 -10 to 10 -13 T. To detect such a weak magnetic field, a highly sensitive sensor such as a skid is used. It is essential. However, since the skid sensor is also a microwave sensor, it is susceptible to electromagnetic interference and must be used in an environment in which not only external magnetic noise but also radio noise due to broadcast waves and communication radio waves are shielded.
【０００３】この電波ノイズをシールドする技術として
は特開昭６２−１７５６８１号公報に見られるように非
磁性の金属薄板を極低温容器外層ＦＲＰ（繊維強化プラ
スチック）部に埋設する技術や、内，外層壁間に熱絶縁
材として用いられるアルミ蒸着を施したマイラフィルム
を流用する技術がある。As a technique for shielding this radio noise, a technique of embedding a non-magnetic thin metal plate in the outer layer FRP (fiber reinforced plastic) of a cryogenic container as shown in JP-A-62-175681, and There is a technique that uses a Mylar film that has been vapor-deposited with aluminum and that is used as a heat insulating material between the outer layers.
【０００４】[0004]
【発明が解決しようとする課題】上記のように、従来技
術においては非磁性の金属薄板を外層ＦＲＰ部に埋設し
たり、熱絶縁材を流用する技術が発案されているが、い
ずれも渦電流の発生を防止するために金属薄板及び熱絶
縁材に切り欠きが入れてあり、閉ループ構造をとらない
ようになっている。しかしながら、この切り欠き部の存
在により新たに静電気によるノイズの発生や切り欠き部
からの外来電波の侵入などの問題が生じていた。また熱
絶縁材の中には静電気対策として切り欠き端部が短絡さ
れアースされたものもあるが、逆に渦電流の発生を招
き、これに誘起されて磁気ノイズが発生するという問題
点があった。As described above, in the prior art, a technique of embedding a non-magnetic thin metal plate in the outer layer FRP portion or diverting a heat insulating material has been proposed. The metal thin plate and the heat insulating material are notched to prevent the occurrence of the above, so that the closed loop structure is not taken. However, due to the presence of the cutout portion, new problems such as generation of noise due to static electricity and entry of external radio waves from the cutout portion have occurred. Some of the thermal insulation materials have their cutout ends short-circuited and grounded as a countermeasure against static electricity, but on the contrary, they cause the generation of eddy currents, which causes the problem that magnetic noise is generated. It was
【０００５】この発明は上記のような問題点を解消する
ためになされたもので、渦電流の発生により誘起される
磁気ノイズを抑え、且つ外来電波ノイズの侵入を防止す
ることが可能なスキッドセンサー用極低温容器を得るこ
とを目的とする。The present invention has been made to solve the above-mentioned problems, and is a skid sensor capable of suppressing magnetic noise induced by the generation of eddy currents and preventing intrusion of external radio wave noise. The purpose is to obtain a cryogenic container.
【０００６】[0006]
【課題を解決するための手段】この発明のスキッドセン
サー用極低温容器は、容器を形成する外層壁部を非磁性
で導電性のＦＲＰで、内層壁部を非磁性で非導電性のＦ
ＲＰで形成するようにしたものである。In the cryogenic container for a skid sensor of the present invention, the outer layer wall portion forming the container is made of a non-magnetic and conductive FRP, and the inner layer wall portion is made of a non-magnetic and non-conductive FRP.
It is formed by RP.
【０００７】そして、所定の導電率を有する導電性ＦＲ
Ｐを用いて外層壁部を形成し、所望の外来電波のカット
オフ周波数が得られるようにしたものである。Then, a conductive FR having a predetermined conductivity
The outer layer wall portion is formed by using P so that a desired cutoff frequency of the external radio wave can be obtained.
【０００８】[0008]
【作用】この発明におけるスキッドセンサー用極低温容
器においては、容器外層壁部に導電性のＦＲＰを用いて
いるので外来電波の侵入を防止することができ、且つ発
生する渦電流が非常に小さく、これによって誘起される
磁気ノイズもセンサー感度と比べて非常に微弱であるた
め渦電流による問題もない。In the cryogenic container for a skid sensor according to the present invention, since the conductive FRP is used for the outer wall of the container, it is possible to prevent the intrusion of external radio waves, and the generated eddy current is very small. The magnetic noise induced by this is also extremely weak compared to the sensor sensitivity, so there is no problem due to eddy currents.
【０００９】また、外層壁部のＦＲＰの導電率をコント
ロールすることにより外来電波のカットオフ周波数を任
意に選択できる。Further, the cutoff frequency of external radio waves can be arbitrarily selected by controlling the conductivity of the FRP on the outer wall.
【００１０】[0010]
実施例１．図１はこの発明の一実施例のスキッドセンサ
ー用極低温容器を示す縦断面構成図である。この極低温
容器１は外層２と内層３からなる二重構造となってお
り、両層間に熱絶縁のための真空部４が設けられてい
る。内層３には液体ヘリウムなどの寒剤が満たされてお
り、その中にスキッドセンサー６が収納されている。内
層３はスキッドセンサー６との距離が近く、渦電流によ
る影響も大きいので、その壁には非磁性で非導電性のＦ
ＲＰ、例えばガラス繊維やアルミナ繊維で強化されたＦ
ＲＰが用いられている。外層２の壁は非磁性で導電性の
ＦＲＰ、例えば炭素繊維で強化されたＦＲＰ（ＣＦＲＰ
と略記する）が用いられている。Example 1. FIG. 1 is a vertical sectional configuration diagram showing a cryogenic container for a skid sensor according to an embodiment of the present invention. This cryogenic container 1 has a double structure composed of an outer layer 2 and an inner layer 3, and a vacuum section 4 for thermal insulation is provided between both layers. The inner layer 3 is filled with a cryogen such as liquid helium, and the skid sensor 6 is housed therein. Since the inner layer 3 is close to the skid sensor 6 and is greatly affected by eddy currents, its wall is made of non-magnetic and non-conductive F
RP, eg F reinforced with glass or alumina fibers
RP is used. The wall of the outer layer 2 is a non-magnetic and conductive FRP, such as a carbon fiber reinforced FRP (CFRP).
Abbreviated) is used.
【００１１】図２は外層２壁部を切り欠いて示す模式断
面図で、図に示すようにＣＦＲＰの炭素繊維７は任意の
角度αi に配向されている。内外層に用いられるＦＲＰ
は繊維を巻回するフィラメントワインディング法やプリ
プレグシートを積層したシートワインディング法などで
成形されたものである。FIG. 2 is a schematic sectional view showing the outer layer 2 wall portion cut away. As shown in the figure, the CFRP carbon fibers 7 are oriented at an arbitrary angle α i . FRP used for inner and outer layers
Is formed by a filament winding method in which fibers are wound or a sheet winding method in which prepreg sheets are laminated.
【００１２】[0012]
【表１】 [Table 1]
【００１３】表１は図１に示す極低温容器１の外層壁材
に使用したＣＦＲＰの繊維配向を変化させた時のＣＦＲ
Ｐの導電率、外来電波のカットオフ周波数及び発生する
渦電流により誘起される磁気ノイズを求めた結果であ
る。表中には非磁性で導電性の金属であるアルミ材の値
も比較のために示してある。表中の σC、ｆは下式によ
り算出している。Table 1 shows the CFR when the fiber orientation of CFRP used for the outer wall material of the cryogenic container 1 shown in FIG. 1 is changed.
It is a result of obtaining the magnetic noise induced by the conductivity of P, the cutoff frequency of the external radio wave, and the eddy current generated. In the table, the value of the aluminum material which is a non-magnetic and conductive metal is also shown for comparison. Σ C and f in the table are calculated by the following formula.
【００１４】[0014]
【数１】 [Equation 1]
【００１５】ここで σ‖：一方向ＣＦＲＰ材の繊維方
向の導電率（Ω-1・ｍ-1） σ⊥：一方向ＣＦＲＰ材の繊維と直角方向の導電率（Ω
-1・ｍ-1） αi：第ｉ層の繊維配向角 Ｎ ：積層数 μ0：４π×１０-7 δ：スキンデプス（ＣＦＲＰ材の厚み ２ｍｍに設定）Where σ ‖ : conductivity in the fiber direction of the unidirectional CFRP material (Ω -1 · m -1 ) σ ⊥ : conductivity in the direction perpendicular to the fiber of the unidirectional CFRP material (Ω
−1 · m −1 ) α i : Fiber orientation angle of the i-th layer N: Number of layers μ 0 : 4π × 10 −7 δ: Skin depth (CFRP material thickness is set to 2 mm)
【００１６】以上の結果からＣＦＲＰ材の繊維の配向角
を変化させることにより広い周波数帯域でカットオフ周
波数が設計でき、且つ渦電流により誘起される磁気ノイ
ズもアルミに比べて非常に微弱で問題のないことがわか
る。即ち、この発明の極低温容器は外層壁にＣＦＲＰを
使用しているので、渦電流の発生により誘起される磁気
ノイズを極く小さく抑えることができ、且つ外来電波ノ
イズの侵入も防止できる効果がある。また、ＣＦＲＰの
導電率をコントロールすることによりカットオフ周波数
を任意に設計できる効果がある。From the above results, the cutoff frequency can be designed in a wide frequency band by changing the orientation angle of the fibers of the CFRP material, and the magnetic noise induced by the eddy current is much weaker than that of aluminum, which is a problem. I know there isn't. That is, since the cryogenic container of the present invention uses CFRP for the outer layer wall, the magnetic noise induced by the generation of the eddy current can be suppressed to a very small level and the intrusion of the external radio wave noise can be prevented. is there. Further, there is an effect that the cutoff frequency can be arbitrarily designed by controlling the conductivity of CFRP.
【００１７】なお、上記実施例ではＣＦＲＰ材の繊維の
配向角を変化させることによりカットオフ周波数を任意
に変える場合について示したが、繊維の体積含有率を変
化させたり、異なった種類のＦＲＰを外層壁部の層間や
層内でハイブリッド化させることによりσ‖を変化させ
カットオフ周波数を任意に設計することも可能である。
例えば外層壁部をグラファイトで構成する場合は黒鉛化
炭素繊維の体積含有率を約１００％にしたときに匹敵
し、またＣＦＲＰの円筒でＧＦＲＰ（ガラス繊維強化プ
ラスチック）製極低温容器を被う場合は外層壁部での層
間ハイブリッド化に匹敵する。In the above embodiment, the cutoff frequency is arbitrarily changed by changing the orientation angle of the fibers of the CFRP material. However, the volume content of the fibers is changed or different kinds of FRP are used. It is also possible to arbitrarily design the cutoff frequency by changing σ ‖ by hybridizing between the layers of the outer layer wall portion or within the layer.
For example, when the outer wall is made of graphite, it is comparable when the volume content of graphitized carbon fiber is set to about 100%, and when a GFRP (glass fiber reinforced plastic) cryogenic container is covered with a CFRP cylinder. Is comparable to the inter-layer hybridization at the outer wall.
【００１８】[0018]
【発明の効果】以上のように、この発明のスキッドセン
サー用極低温容器は、容器の外層壁部に非磁性で導電性
のＦＲＰを用い、内層壁部に非磁性で非導電性のＦＲＰ
を用いることにより、渦電流により誘起される磁気ノイ
ズを最小に抑え、外来の高周波ノイズをシールドする事
が出来る効果がある。INDUSTRIAL APPLICABILITY As described above, the cryogenic container for a skid sensor according to the present invention uses a non-magnetic and conductive FRP for the outer wall of the container and a non-magnetic, non-conductive FRP for the inner wall of the container.
By using, the magnetic noise induced by the eddy current can be minimized, and external high frequency noise can be shielded.
【００１９】また、外層壁部を形成する導電性ＦＲＰの
導電率をコントロールすることにより、シールドする高
周波のカットオフ周波数をコントロールできる効果があ
る。Further, by controlling the conductivity of the conductive FRP forming the outer layer wall portion, there is an effect that the cutoff frequency of the high frequency wave to be shielded can be controlled.
【図１】この発明の一実施例のスキッドセンサー用極低
温容器を示す縦断面構成図である。FIG. 1 is a vertical cross-sectional configuration diagram showing a cryogenic container for a skid sensor according to an embodiment of the present invention.
【図２】この発明の一実施例のスキッドセンサー用極低
温容器外層壁部の切り欠き断面模式図である。FIG. 2 is a schematic cutaway sectional view of an outer wall of a cryogenic container for a skid sensor according to an embodiment of the present invention.
１ スキッドセンサー用極低温容器 ２ 外層 ３ 内層 ５ 寒剤 ６ スキッドセンサー 1 Cryogenic container for skid sensor 2 Outer layer 3 Inner layer 5 Cryogen 6 Skid sensor
Claims (2)
らなり、上記内層内に寒剤が注入され、且つスキッドセ
ンサーが収納されるスキッドセンサー用極低温容器にお
いて、上記外層壁部を非磁性で導電性のＦＲＰで形成
し、上記内層壁部を非磁性で非導電性のＦＲＰで形成す
るようにしたことを特徴とするスキッドセンサー用極低
温容器。1. In a cryogenic container for a skid sensor, which comprises an inner layer and an outer layer formed by FRP, in which a cryogen is injected into the inner layer, and a skid sensor is housed, the outer layer wall is nonmagnetic and electrically conductive. A cryogenic container for a skid sensor, characterized in that the inner wall portion is formed of non-magnetic and non-conductive FRP.
いて外層壁部を形成し、所望の外来電波のカットオフ周
波数が得られるようにしたことを特徴とする請求項第１
項記載のスキッドセンサー用極低温容器。2. The outer layer wall portion is formed by using a conductive FRP having a predetermined conductivity so that a desired cutoff frequency of an external radio wave can be obtained.
A cryogenic container for a skid sensor according to the item.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3328617A JP3002586B2 (en) | 1991-12-12 | 1991-12-12 | Cryogenic container for skid sensor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3328617A JP3002586B2 (en) | 1991-12-12 | 1991-12-12 | Cryogenic container for skid sensor |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH05203711A true JPH05203711A (en) | 1993-08-10 |
| JP3002586B2 JP3002586B2 (en) | 2000-01-24 |
Family
ID=18212274
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP3328617A Expired - Fee Related JP3002586B2 (en) | 1991-12-12 | 1991-12-12 | Cryogenic container for skid sensor |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3002586B2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2018072110A (en) * | 2016-10-27 | 2018-05-10 | 株式会社島津製作所 | Portable magnetic detector |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS58163878U (en) * | 1982-04-27 | 1983-10-31 | 株式会社島津製作所 | superconducting magnetometer |
| JPS62175681A (en) * | 1986-01-29 | 1987-08-01 | Shimadzu Corp | Cryostatic container for skid magnetometer |
-
1991
- 1991-12-12 JP JP3328617A patent/JP3002586B2/en not_active Expired - Fee Related
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS58163878U (en) * | 1982-04-27 | 1983-10-31 | 株式会社島津製作所 | superconducting magnetometer |
| JPS62175681A (en) * | 1986-01-29 | 1987-08-01 | Shimadzu Corp | Cryostatic container for skid magnetometer |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2018072110A (en) * | 2016-10-27 | 2018-05-10 | 株式会社島津製作所 | Portable magnetic detector |
Also Published As
| Publication number | Publication date |
|---|---|
| JP3002586B2 (en) | 2000-01-24 |
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|---|---|---|---|
| LAPS | Cancellation because of no payment of annual fees |