JPS5818810A - Cryogenic insulating conductor - Google Patents

Abstract

(57)【要約】本公報は電子出願前の出願データであるた
め要約のデータは記録されません。(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

【発明の詳細な説明】 本発明は極低温領域で使用される超電動コイル、或は電
源用リード線などの特に大形な極低温用絶縁導体に関す
る。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a particularly large insulated conductor for cryogenic temperatures, such as a superelectric coil used in a cryogenic region or a lead wire for a power supply.

近年エネルギー源・の開発が進められており、核融合関
係の研究も日゛進月歩である。それに関連して超電導コ
イル等の開発も進められてｈる。In recent years, the development of energy sources has been progressing, and research related to nuclear fusion is progressing day by day. In connection with this, the development of superconducting coils and the like is also progressing.

従来絶縁線輪゛は、コロナ劣化が問題となる高醒圧機種
では導体にマイカ゛テープ等？゛巻′回゛踵す゛たコロ
ナ劣化が問題とならない低電圧機種では導体に有機フィ
ルム等を巻回した後、樹脂−を真空含浸法などｋよ抄含
浸させて加熱硬化し、導゛体と絶縁層とが一体化した強
固な絶縁線輪としている。For conventional insulated wire rings, for high-pressure models where corona deterioration is a problem, do you use mica tape, etc. on the conductor? For low-voltage models in which corona deterioration due to winding is not a problem, the conductor is wound with an organic film, etc., and then impregnated with resin using a vacuum impregnation method or the like and heated to harden. The insulating layer is integrated into a strong insulating wire ring.

にあ）、ｉ電圧であるので、その絶縁は本質的に後者に
属する本のと考えられる。しかし、極低温にさらされる
ため、従来前えられなかった熱膨張係数の差に起因する
応力が導体と絶縁層間、および絶縁層内部に発生する。(2), i voltage, so the insulation is considered to essentially belong to the latter category. However, due to the exposure to extremely low temperatures, stress occurs between the conductor and the insulating layer and inside the insulating layer due to the previously unprecedented difference in coefficient of thermal expansion.

現在極低゛温領域て使用さｈる有機薄−材料には、ポリ
イミド系フィルム（カプトンと称するデュポン社商品名
のものあ））、アラミツド紙（ノーメックスと称するデ
ュポン社商品名″のものあシ）の他、ポリフッ化エチレ
ンフィルム、ポリエステルフィルム等があ）、又、それ
らを積層板としたものもあるが、単独で極低温にさらさ
れても問題は少ない。これらの薄葉材料を導体に、また
お互いに接着させるための樹脂類は、常温近辺で柔軟性
に優れて−たとしても、極低温下ではその分子運動は凍
結されて、柔軟性を失い、硬く脆いものになる。従って
、導体と絶縁層を樹脂で完全に一体硬化した場合、ヒー
トサイクルもしくは急激なり−ルダウツ衝撃が加わった
場合、導体と絶縁層との熱膨張率の違いに起因する亀裂
が絶縁層に入り、進展して絶縁を完全に損傷する可能性
がある。Organic thin materials currently used in the cryogenic temperature range include polyimide films (Kapton, a DuPont product name) and aramid paper (DuPont product name Nomex). ), there are also polyfluoroethylene films, polyester films, etc.), and there are also laminates made of these, but there are few problems even if they are exposed alone to extremely low temperatures.These thin film materials can be used as conductors, Furthermore, even if the resins used to bond each other are highly flexible at room temperature, their molecular motion is frozen at extremely low temperatures, causing them to lose their flexibility and become hard and brittle. If the conductor and insulating layer are completely cured with resin, if a heat cycle or sudden shock is applied, cracks due to the difference in thermal expansion coefficient between the conductor and the insulating layer will enter the insulating layer and propagate. Can permanently damage insulation.

本発明は絶縁層内部に緩和層を設けて、亀ｇ！に対し信
頼性の高い極低温用絶縁導体を提供することを目的とす
る。In the present invention, a relaxation layer is provided inside the insulating layer, and the turtle g! The purpose of this research is to provide a highly reliable insulated conductor for cryogenic temperatures.

以下、本発明の一実施例につｂて、第１図および第２図
を参照して説明する。Hereinafter, one embodiment of the present invention will be described with reference to FIGS. 1 and 2.

導体（１）の外周部に、片面エポキシ樹脂処理した厚さ
２ミルのプリプレグ状のアラミツド紙（２）を１／２重
ねで２回巻回する。その上に無処理の厚さ２ミルのアラ
ミツド紙（３）を１／２重ねで２回巻回し、その端部だ
けは前記プリプレグアラミツド紙＋２）　ｔｌ″巻回す
る。更にその上に％前記プリプレグアラミツド紙（２）
を１／２重ねで２回巻回する。これを加熱して樹脂処理
部分を硬化し、プリプレグアラミツド紙（２）の硬化し
た内側および外側固化絶縁層（４）。Around the outer periphery of the conductor (1), prepreg-like aramid paper (2) having a thickness of 2 mils and treated with epoxy resin on one side is wound twice in a 1/2 overlap. On top of that, untreated aramid paper (3) with a thickness of 2 mils is wound twice in a 1/2 overlap, and only the ends of the prepreg aramid paper (3) are wrapped with the prepreg aramid paper + 2) tl''. Said prepreg aramid paper (2)
Wrap twice with 1/2 overlap. This is heated to harden the resin-treated portion, and the inner and outer hardened insulating layers (4) of the prepreg aramid paper (2) are cured.

（５）間に１無処理アラミツド紙のｔｔで硬化した緩和
層（６）からなる絶縁層（７）を有し、端部は封止部（
８）を有する絶縁導体を形成する。(5) In between, there is an insulating layer (7) consisting of a relaxing layer (6) cured by TT of untreated aramid paper, and the end is a sealing part (
8) to form an insulated conductor having the following properties.

このようにすると、薄葉材料が一体硬化した固化絶縁層
（４）　、　（５）の間に薄葉材料の動きが比較的自由
な緩和層（６）が介在するために、急激な冷却や、ヒー
トサイクルによって導体（１）Ｋ隣接した内側固化絶縁
層（４１に亀裂が発生したとしても、緩和層（６）で亀
１１は無処理アラミツド紙（３）である薄葉材料の移動
によって吸収され、外側の固化絶縁層（５）には進展し
な匹。逆に絶縁層（７）外部から急冷された場合、外側
固化絶縁層（５）Ｋ亀裂が生じても、やはり緩和層（６
）で吸収され、内側固化絶縁層（４）は損−を受けなｉ
ｏまた端部は封止部＋８）があるから緩和層＋６）Ｋ水
分が入ることがない。In this way, the relaxation layer (6) in which the movement of the thin sheet material is relatively free is interposed between the solidified insulating layers (4) and (5) where the thin sheet material is integrally cured, so that rapid cooling and heat Even if a crack occurs in the inner solidified insulating layer (41) adjacent to the conductor (1) K due to the cycle, the crack 11 in the relaxation layer (6) will be absorbed by the movement of the thin material, which is untreated aramid paper (3), and the outer On the other hand, if the insulating layer (7) is rapidly cooled from the outside, even if a crack occurs in the outer solidified insulating layer (5), it will not develop into the relaxed layer (6).
), and the inner solidified insulating layer (4) receives no loss i.
o Also, since there is a sealing part +8) at the end, moisture cannot enter the relaxation layer +6).

この実施例の効果をみる為に、同一形状の導体に片面エ
ポキシ樹脂処理し九厚さ２ミルのプリプレグアラミツド
紙を１／２重ねで６回巻回し、加熱硬化した従来構造の
絶縁導体を製作し、短時間上昇法で破壊電圧値を比較し
てみた。初期破壊電圧は本実施例、のものが１８．７Ｋ
Ｖ／■、従来のものが２０、Ｉ　ＫＶ／闘で従来のもの
の方が良好であつ九が、液体窒素による冷却と、室温に
戻す繰返しＫよるヒートサイクルを実施したところ、数
ｌＯサイクル後に絶縁破壊電圧値が逆転する現象が見ら
れ、本実施例のものの方が、と−トサイクルの影響が小
さいことが判明した。In order to see the effect of this example, an insulated conductor of the conventional structure was prepared by wrapping a conductor of the same shape with epoxy resin treatment on one side and wrapping 2 mil thick prepreg aramid paper 6 times in a 1/2 overlap. We fabricated one and compared the breakdown voltage values using the short-time rise method. The initial breakdown voltage of this example is 18.7K.
V/■, the conventional one was 20, I KV/T, the conventional one was better, and when the heat cycle was performed by cooling with liquid nitrogen and repeatedly bringing it back to room temperature, the insulation failed after several lO cycles. A phenomenon in which the breakdown voltage value was reversed was observed, and it was found that the effect of the breakdown cycle was smaller in the case of this example.

次に他の実施例として、プリプレグアラミツド紙（２）
の代）Ｋガラス繊維プリプレグ薄葉材料を用いた場合を
検討した０ この場合は、接着樹脂の偏在部を中心として進展する亀
裂は重大なことが解った。薄葉材料を中間に配すると、
薄葉材料の破壊電圧が高いことから、初期破壊電圧も当
然向上したが、完全にガラス繊維と接着させると、ガラ
ス線維や樹脂分の多い部分に割れが入シ、亀裂が発生し
て強度の鵠い薄葉材料にも亀裂が進展することが見出さ
れた。Next, as another example, prepreg aramid paper (2)
In this case, it was found that the cracks that grow mainly in the unevenly distributed areas of the adhesive resin are serious. By placing thin leaf material in the middle,
Since the breakdown voltage of the thin material is high, the initial breakdown voltage was naturally improved, but if it was completely bonded to the glass fiber, cracks would occur in the areas with a large amount of glass fiber or resin, which would reduce the strength. It was also found that cracks grow even in thin thin-sheet materials.

そこで、ｖＭ１図および！４２図の実施例のように、無
処理の薄葉材料（３）を少なくとも２層設ければ、ヒー
トサイクルに対して信頼性の高い絶縁導体となることが
判明した。So, vM1 diagram and! It has been found that by providing at least two layers of untreated thin sheet material (3) as in the example shown in FIG. 42, an insulated conductor with high reliability against heat cycles can be obtained.

第３図に示す他の実施例は無処理の薄葉材料（９）。Another example shown in FIG. 3 is an untreated thin sheet material (9).

（９）の間に離形性の良好な薄葉材料ａ・としてテフロ
ン（デュポン社商品名）テープを巻回しておき、無処理
の薄葉材料＋９）　、　（９）に樹脂を含浸硬化したも
のである。Between (9), Teflon (trade name of DuPont) tape was wound as a thin sheet material with good mold release properties, and untreated thin sheet material +9), (9) was impregnated with resin and hardened. be.

このようにすれば離形性薄葉材料ａ・が樹脂に処理され
な＾で緩和層（６）（第２図参照）として作用するから
、中はり亀裂の進展、しない高信頼性の絶縁導体となる
。In this way, the releasable thin sheet material a. acts as a relaxing layer (6) (see Figure 2) without being treated with resin, resulting in a highly reliable insulated conductor that does not cause the propagation of hollow cracks. Become.

冑、本発明は上記し、かつ図面に示した実施例のみに限
定されるものではなく、例えば固化絶縁層と緩和層を交
互に多段に配してもよい等、その要旨を変更しない範囲
で、檎々変形して実施できることは勿論である。However, the present invention is not limited to the embodiments described above and shown in the drawings; for example, solidified insulating layers and relaxation layers may be arranged alternately in multiple stages, without changing the gist thereof. Of course, it can be implemented with various modifications.

以上説明したように、本発明によれば、複数層の樹脂錫
塩された薄葉材料層からなる固化絶縁層の間に無処理の
薄葉材料層からなる緩和層を設けたので、その製造は非
常に簡単容易でありながら、低電圧の極低温領域で使用
する場合に絶縁層の亀裂に対する信頼性が極めて向上し
た極低温用絶縁導体が得られる。As explained above, according to the present invention, the relaxation layer made of an untreated thin material layer is provided between the solidified insulating layers made of a plurality of resin tin salt thin film material layers, so the manufacturing process is very easy. It is possible to obtain an insulated conductor for cryogenic use which is simple and easy to use, and which has extremely improved reliability against cracking of the insulating layer when used in a low voltage cryogenic region.

【図面の簡単な説明】[Brief explanation of the drawing]

＄１図は本発明の極低温用絶縁導体の一実施例の製造途
中の要部を拡大して示す縦断面図、８２図は第１図の製
造後の状態を模式的に示した縦断面図、第３図は他の実
施例の製造途中の要部を拡大して示す縦断面図である。 １・・・導体 ２・・・樹脂処理薄葉材料であろプリプレグアラミツド
紙３・・・無処理薄葉材料であるアラミツド紙４・・内
側固化絶縁層　　５・外側固化絶縁層６・・・緩和層　
　　　　　７　絶縁層９　無処理薄葉材料　　１０・・
離形性薄葉材料代理人　弁理士　　井　上　−男Figure 1 is an enlarged vertical cross-sectional view showing the essential parts of an embodiment of the cryogenic insulated conductor of the present invention during manufacture, and Figure 82 is a vertical cross-sectional view schematically showing the state of Figure 1 after manufacture. 3 are longitudinal cross-sectional views showing enlarged main parts of another embodiment during manufacture. 1... Conductor 2... Prepreg aramid paper, which may be resin-treated thin material 3... Aramid paper, which is untreated thin material 4... Inner hardened insulating layer 5. Outer solidified insulating layer 6... Relaxation layer
7 Insulating layer 9 Untreated thin material 10...
Agent for releasable thin film material Patent attorney Mr. Inoue

Claims (3)

【特許請求の範囲】[Claims] （１）導体の周囲に薄葉材料を巻回して絶縁層を設けた
極低温用絶縁導体において、複数層の樹脂処理された薄
葉材料層から°なる固化絶縁層の間に無処理の薄葉材料
層からなる緩和層を設は念ことを％黴とする極低温゛用
絶縁導体。(1) In a cryogenic insulated conductor in which an insulating layer is provided by winding a thin sheet material around the conductor, an untreated thin sheet material layer is placed between a solidified insulating layer consisting of multiple resin-treated thin sheet material layers. An insulated conductor for extremely low temperatures with a relaxation layer made of mold. （２）樹脂処理された薄葉材料層はガラス繊維フリプレ
グ層を硬化させたものとし、キの中間の無処理の薄葉材
料層は複数層重ねたものとしたことを特徴とする特許請
求の範囲１８１項記斂の極□　低温用絶縁導体。(2) The resin-treated thin material layer is a hardened glass fiber flip-preg layer, and the untreated thin material layer in the middle of Q is a plurality of stacked layers.Claim 181 Insulated conductor for low temperature. （３）樹脂処理された薄東材□料輸は樹脂金浸によった
ものとし、無処理の薄葉材料層は鐘形性薄葉材料層とし
たことを特徴とする特許請求の範囲第１項記載の極低温
用絶縁導体。(3) The resin-treated Usutongzai □ material is one obtained by resin-gold immersion, and the untreated thin-sheet material layer is a bell-shaped thin-sheet material layer. Insulated conductor for cryogenic temperatures.