JP3940702B2

JP3940702B2 - Insulating post

Info

Publication number: JP3940702B2
Application number: JP2003151712A
Authority: JP
Inventors: 晃一岩本
Original assignee: Kyocera Corp
Current assignee: Kyocera Corp
Priority date: 2003-05-28
Filing date: 2003-05-28
Publication date: 2007-07-04
Anticipated expiration: 2023-05-28
Also published as: JP2004354186A

Description

【０００１】
【発明の属する技術分野】
本発明は、核融合実験装置等に用いられる中性粒子加熱装置の真空容器内において荷電粒子等を加速して加速ビームを生成するために電圧を印加する部分に使用される絶縁支柱に関するものである。
【０００２】
【従来の技術】
従来より、核融合実験装置等に用いられる中性粒子加熱装置では、荷電粒子を加速して加速ビームを生成するための電圧を印加する部分、即ち加速電極等の支持部材などとして絶縁支柱が用いられている。この絶縁支柱の基本構成を図３に斜視図で示す。また、この絶縁支柱における絶縁柱と電極部材との接合部の拡大断面図を図２に示す。図２，図３において、11は絶縁柱、12は加速電極等に接続される電極部材、17はネジ穴、18はボルト等のネジであり、主にこれらで絶縁支柱は構成されている。
【０００３】
この図２の絶縁支柱において、絶縁柱11は、酸化アルミニウム（Ａｌ_２Ｏ_３）質焼結体等のセラミックスからなり、その各端面に１つあるいは複数のネジ穴17が形成されている。また、電極部材12およびネジ18はＳＵＳ等の金属から成る。
【０００４】
なお、絶縁柱11と電極部材12の接合は、電極部材12に予め絶縁柱11のネジ穴17に対応する位置に貫通孔をあけておき、その電極部材12を絶縁柱11の両端面にあて、ネジ18を電極部材12の貫通孔に挿通させて絶縁柱11のネジ穴17にネジ込んで締め付けることによって機械的に接合している。（例えば、下記の特許文献１参照）。
【０００５】
また、ネジ穴17には、ステンレススチール（ＳＵＳ）等の金属から成る筒状でその内側面および外側面にネジ加工が施されたヘリサートが挿入されていてもよく、この場合、ヘリサートの外側面が絶縁柱11のネジ穴17にネジ込まれるとともに内側面のネジ加工部にネジ18がネジ込まれ、絶縁柱11に対するネジ18の締め付けをより強固なものとすることができる。
【０００６】
【特許文献１】
特開2002−343292号公報（第８頁、図７）
【０００７】
【発明が解決しようとする課題】
しかしながら、上記従来の絶縁支柱においては、図２のようにネジ穴17がセラミックスから成る絶縁柱11に直接ネジ加工が施されているため、絶縁柱11のネジ穴17にネジをネジ込んで締め付けることにより電極部材12を機械的に接合すると、ネジ18を介してネジ穴17のネジ加工部に引っ張り応力や剪断応力等の応力が加わり、ネジ穴17のネジ加工部にカケ，クラック等の破損が発生し易くなっていた。
【０００８】
このようなネジ穴17のネジ加工部に破損が生じると、絶縁柱11に対するネジ18の締め付け強度が低下して、絶縁柱11と電極部材12を強固に接合できなくなり、絶縁支柱として機能を果たさなくなるという問題点があった。
【０００９】
特に近時では核融合実験装置における中性粒子加熱装置は大型化しており、それに伴ってネジ18を介してネジ穴17のネジ加工部に加わる引っ張り応力や剪断応力等の応力が大きくなって、絶縁柱11のネジ加工部の破損が顕著に現れるようになってきた。
【００１０】
また、電極部材12を加速電極等に接続し高い電圧を印加すると、絶縁柱11の両端面にネジ込まれたネジ18にも高い電圧が加わり、ネジ18の角部から対向するネジ18に向けて放電が起きやすくなるという問題点もあった。
【００１１】
従って、本発明は上記問題点に鑑み完成されたものであり、その目的は、電極部材を絶縁柱に強固にネジ止めしても絶縁柱を破損させることがなく、絶縁柱と電極部材との接合の信頼性を高くすることができるとともに、ネジからの放電を解消して、長期にわたって正常に機能する絶縁支柱を提供することにある。
【００１２】
【課題を解決するための手段】
本発明の絶縁支柱は、互いに対向配置されるとともにそれぞれ上下面を貫通する貫通孔が複数個形成された、金属からなる２つの円環状の電極部材と、両端面に凹部が形成されており、該凹部が前記貫通孔と同軸状となるようにして前記両端面が前記２つの電極部材の対向する主面にそれぞれ接合された、セラミックスからなる複数の円柱状の絶縁柱と、前記凹部に嵌入ロウ付けされた、金属からなる円筒状のネジ止め部材と、前記貫通孔に挿入されるとともに前記ネジ止め部材にネジ込まれることによって、前記電極部材と前記絶縁柱とをネジ止めしているネジとを具備しており、前記凹部は、横断面形状が円形状であるとともに底面が凹んだ曲面とされており、その内面の全面にメタライズ層が形成されていることを特徴とする。
【００１３】
本発明は、互いに対向配置されるとともにそれぞれ上下面を貫通する貫通孔が複数個形成された、金属からなる２つの円環状の電極部材と、両端面に凹部が形成されており、この凹部が貫通孔と同軸状となるようにして両端面が２つの電極部材の対向する主面にそれぞれ接合された、セラミックスからなる複数の円柱状の絶縁柱と、凹部に嵌入ロウ付けされた、金属からなる円筒状のネジ止め部材と、貫通孔に挿入されるとともにネジ止め部材にネジ込まれることによって、電極部材と絶縁柱とをネジ止めしているネジとを具備しており、凹部は、横断面形状が円形状であるとともに底面が凹んだ曲面とされており、その内面の全面にメタライズ層が形成されていることより、セラミックス製の絶縁柱に欠けなどの破損が発生し易いネジ加工を施すことなくネジ止めすることができるため、電極部材の対向する主面に絶縁柱を接合する際のネジ止め時に、絶縁柱にカケ，クラック等の破損が発生するのを有効に抑制することができる。
【００１４】
また、ネジ止め部材と絶縁柱とを接合するロウ材がネジ止めによる応力を有効に緩和することができるため、絶縁柱の破損を防止する効果をより向上させることができる。その結果、近時の核融合実験装置における中性粒子加熱装置に用いられる大型の絶縁支柱においても、絶縁柱にカケ，クラック等の破損が発生するのを有効に抑制することができる。
【００１５】
さらに、絶縁柱の両端面に形成された凹部は、横断面形状が円形状であるとともに底面が凹んだ曲面とされており、その内面の全面にメタライズ層が形成されているため、電極部材を加速電極等に接続して高い電圧を印加した際、ネジに生じる電荷は角部に集中することなく凹部内面の滑らかな曲面状のメタライズ層全面に分散させることができ、対向するネジ間での放電を有効に抑制することができる。
【００１６】
また本発明の絶縁支柱において、好ましくは、前記ネジ止め部材の厚みが0.5乃至2.5ｍｍであることを特徴とする。
【００１７】
本発明の絶縁支柱は、ネジ止め部材の厚みが0.5乃至2.5ｍｍであることにより、絶縁柱にネジ止め部材をロウ付けする際に発生する熱膨張差による応力で絶縁柱にカケ，クラック等の破損が発生するのを防止できるとともに、ネジ止め部材が変形してネジ止めできなくなるのを防止できる。その結果、長期にわたってより正常に機能する絶縁支柱を提供することができる。
【００１８】
【発明の実施の形態】
本発明の絶縁支柱について以下に詳細に説明する。図１は本発明の絶縁支柱における絶縁柱と電極部材との接合部断面図である。図１において、１は絶縁柱、２は電極部材、３はネジ止め部材、４は凹部、５はロウ材であり、主にこれらで絶縁支柱は構成されている。
【００１９】
そして、本発明の絶縁支柱は、互いに対向配置されるとともにそれぞれ上下面を貫通する貫通孔が複数個形成された、金属からなる２つの円環状の電極部材２と、両端面に凹部４が形成されており、この凹部４が貫通孔と同軸状となるようにして両端面が２つの電極部材２の対向する主面にそれぞれ接合された、セラミックスからなる複数の円柱状の絶縁柱１と、凹部４に嵌入ロウ付けされた、金属からなる円筒状のネジ止め部材３と、貫通孔に挿入されるとともにネジ止め部材３にネジ込まれることによって、電極部材２と絶縁柱１とをネジ止めしているネジ８とを具備しており、凹部４は、横断面形状が円形状であるとともに底面が凹んだ曲面とされており、その内面の全面にメタライズ層４ａが形成されている。
【００２０】
本発明の絶縁柱１は、断面形状が円形、または四角形，六角形等の多角形のものであり、Ａｌ_２Ｏ_３質焼結体等のセラミックスから成る。絶縁柱１の両端面には、底面が凹んだ曲面、例えば球面状，放物線状の曲面となった凹部４が形成され、凹部４内全面にモリブデン（Ｍｏ），マンガン（Ｍｎ），タングステン（Ｗ）等から成るメタライズ層４ａが形成されている。
【００２１】
メタライズ層４ａは、ネジ止め部材３をロウ付けする際の下地金属層として作用するとともに、電極部材２を加速電極等に接続して高い電圧を印加した際、ネジ８に生じる電荷を角部に集中することなく分散させる作用もする。このようなメタライズ層４ａは、好ましくはその表面にロウ材５との濡れ性に優れるニッケル（Ｎｉ），金（Ａｕ）等の金属をメッキ法により１〜10μｍ程度の厚みに被着させるとよく、メタライズ層４ａにネジ止め部材３を強固にロウ付けすることができる。また、凹部４の開口部には面取りが施されていてもよく、これによりネジ止め部材３と凹部４とを接合するロウ材５のメニスカスを良好なものとし、ネジ止め部材３を凹部４に強固にロウ付けすることができる。
【００２２】
絶縁柱１の両端面に形成された凹部４は、横断面形状が円形状であるとともに底面が凹んだ曲面とされており、その内面の全面にメタライズ層４ａが形成されているため、電極部材２を加速電極等に接続して高い電圧を印加した際、ネジに８生じる電荷は角部に集中することなく凹部４内面の滑らかな曲面状のメタライズ層４ａ全面に分散させることができ、対向するネジ８間での放電を有効に抑制することができる。
【００２３】
電極部材２は、円環部に上下面を貫通する断面形状が円形の貫通孔が同じ間隔で複数個形成された円環状の金属部材であり、ＳＵＳ等から成る。その貫通孔にＳＵＳ等から成るネジ８が挿入されるとともにネジ止め部材３にネジ込まれることによって、電極部材２は絶縁柱１に接合されている。
【００２４】
好ましくは、電極部材２の表面は凹凸が小さくなっているのがよく、具体的にその表面の算術平均粗さ（Ｒａ）はＲａ≦0.4μｍとなっているのがよい。この場合、電極部材２に電圧を印加し電子等の荷電粒子を加速させる際、電極部材２間での微少放電の発生を有効に抑えられ、安定して高電圧を印加することができる。なお、電極部材２に形成される貫通孔は、４〜６個程度である。
【００２５】
ネジ止め部材３は、内周面にネジ加工が施された筒状の金属部材から成り、絶縁柱１の凹部４に嵌め込まれて銀（Ａｇ）ロウ，Ａｇ−銅（Ｃｕ）ロウ等のロウ材５によってロウ付けされる。例えば、ネジ止め部材３はＦｅ−Ｎｉ−Ｃｏ合金等のように絶縁柱１のセラミックスと熱膨張率の近い材料から成るのがよく、ネジ止め部材３を絶縁柱１にロウ付けする際に熱膨張差が発生するのを抑制し、絶縁柱１にクラック等の破損が発生したり、ネジ止め部材３が変形するのを防止する。
【００２６】
また、ネジ止め部材３と凹部４の内面のメタライズ層４ａとを接合するロウ材５は、メタライズ層４ａの全面に被着しているのがよい。これにより、ロウ材５とメタライズ層４ａとの密着性をより向上させることができるとともに、ネジ止め部材３の下端面とメタライズ層４ａとの間にはみ出したロウ材５に放電が生じるのをより有効に抑制することができる。
【００２７】
また、ネジ止め部材３は筒状となっているため、ネジ止め部材３を凹部４のメタライズ層４ａにロウ材５でロウ付けした後にネジ止め部材３下側のメタライズ層４ａにおけるロウ材５の流れの状態を確認でき、ネジ止め部材３と凹部４との接合面全面にわたってロウ付けできているかどうかを目視で確認できる。
【００２８】
好ましくは、ネジ止め部材３の厚みは0.5乃至2.5ｍｍであるのがよく、この構成により、絶縁柱１にネジ止め部材３をロウ付けする際に発生する熱膨張差による応力で絶縁柱１にカケ，クラック等の破損が発生するのを防止できるとともに、ネジ止め部材３が変形してネジ８をネジ止めできなくなるのを防止できる。厚みが0.5ｍｍより小さいと、ネジ止め部材３を絶縁柱１にロウ付けする際に熱膨張差によって変形してネジ８をネジ止めし難くなる。一方、厚みが2.5ｍｍを超えると、ネジ止め部材３と絶縁柱１とのロウ付け時に熱膨張差による大きな応力がこれらの間に生じ、この応力によって絶縁柱１にクラック等の破損が発生し易くなる。
【００２９】
なお、ネジ止め部材３の厚みとは、ネジ止め部材３の内周面に形成されたネジ山の頂点とネジ止め部材３の外側側面との距離のことである。
【００３０】
また、ネジ止め部材３は、内周面に形成されたネジ加工が下端部に達していないことがより好ましい。これにより、ネジ止め部材３の下端部周辺に、電荷が集中し易い尖った部分がなくなり、ネジ止め部材３に放電が生じるのをより有効に抑制することができる。
【００３１】
また、ネジ８は、ネジ底が平坦となっており、ネジ止め部材３にネジ込まれてネジ８のネジ底とネジ止め部材３の下端部とが面一になるようにネジ止めされているのがよい。これにより、ネジ８のネジ底やネジ止め部材３の下端部に電荷が集中するのをより有効に抑制することができ、ネジ８やネジ止め部材３に放電が生じるのをより有効に抑制することができる。
【００３２】
【実施例】
本発明の実施例について以下に説明する。
【００３３】
図１に示す構成のものを以下のようにして作製した。
【００３４】
純度99重量％のＡｌ_２Ｏ_３質焼結体から成る、直径80ｍｍ、長さ290ｍｍの円柱状の絶縁柱１を用意した。絶縁柱１の両端面にはそれぞれ直径15ｍｍで深さ26ｍｍの凹部４が２カ所設けられていた。凹部４の底角部は半径５ｍｍの円弧状の曲面となっており、開口部は３ｍｍの面取りが施されていた。
【００３５】
そして、絶縁柱１の両端面の全面，凹部４の内面及び面取り部の全面にＭｏとＭｎとシリカ（ＳｉＯ_２）をそれぞれ89重量％、６重量％、５重量％の割合で含有する金属ペーストを、10μｍの厚さとなるように印刷塗布し、乾燥後、加湿したフォーミングガス中で1400℃の温度で焼成した。こうして、絶縁柱１の両端面の全面，凹部４の内面及び面取り部の全面にＭｏ−Ｍｎ合金から成るメタライズ層４ａを被着させた。その後、メタライズ層４ａ上にＮｉメッキ層を電解メッキ法により約２μｍの厚さで被着させた。
【００３６】
次に、絶縁柱１の凹部４に外側の直径が15ｍｍで内側の全長にわたってＭ10（ＪＩＳＢ0123による）のネジ加工が施され（これによりネジ止め部材３の厚みは2.5ｍｍとなった）、長さ21ｍｍの円筒状で外側表面のＲａが6.3μｍのＦｅ−Ｎｉ−Ｃｏ合金から成るネジ止め部材３を嵌め込んで、メタライズ層４ａにネジ止め部材３の外側面をロウ材５でロウ付け固定した。このとき、絶縁柱１の凹部４の面取り部とネジ止め部材３との間に、直径１ｍｍのワイヤー状のＡｇ−Ｃｕ合金から成るロウ材５を直径15ｍｍのリング形状にして設置し、それを820℃に加熱して接合させた。これにより、製作されたものをサンプルＡ１とした。
【００３７】
さらに、ネジ止め部材３の内側のネジ加工部をＭ11としたサンプルＡ２（ネジ止め部材３の厚みは２ｍｍ），ネジ加工部をＭ12としたサンプルＡ３（ネジ止め部材３の厚みは1.5ｍｍ），ネジ加工部をＭ13としたサンプルＡ４（ネジ止め部材３の厚みは１ｍｍ），ネジ加工部をＭ14としたサンプルＡ５（ネジ止め部材３の厚みは0.5ｍｍ）をそれぞれ作製した。
【００３８】
比較例としてサンプルＡ１と同じ絶縁柱１の凹部４部に外側の直径が15ｍｍで内側の全長にわたってＭ９（ＪＩＳＢ0123による）のネジ加工が施され（これによりネジ止め部材３の厚みは３ｍｍとなった）、長さ21ｍｍの円筒状で外側表面のＲａが6.3μｍのＦｅ−Ｎｉ−Ｃｏ合金から成るネジ止め部材３を嵌め込んで、メタライズ層４ａにネジ止め部材３の外側面をロウ材５でロウ付け固定した。接合の方法はサンプルＡ１と同じとした。これにより製作されたものをサンプルＢとした。
【００３９】
また、比較例としてサンプルＡ１と同じ絶縁柱１の凹部４部に外径の直径が14.8ｍｍで内側の全長にわたってＭ１４（ＪＩＳＢ0123による）のネジ加工が施され（これによりネジ止め部材３の厚みは0.4ｍｍとなった）、長さ21ｍｍの円筒状で外側表面のＲａが6.3μｍのＦｅ−Ｎｉ−Ｃｏ合金から成るネジ止め部材３を嵌め込んで、メタライズ層４ａにネジ止め部材３の外側面をロウ材５でロウ付け固定した。接合の方法はサンプルＡ１と同じとした。これにより製作されたものをサンプルＣとした。
【００４０】
サンプルＡ１〜Ａ５，Ｂ，Ｃのぞれぞれについて、ネジ止め部材３のネジ加工部に適合するボルト８を挿入し、65Ｎ・ｍのトルクを加え試験を行った。
【００４１】
サンプルＡ１〜Ａ５は65Ｎ・ｍトルクでも破壊しなかった。
【００４２】
サンプルＢはロウ付け時に絶縁柱１の凹部４を起点とするクラックが発生した。
【００４３】
サンプルＣでは、ネジ止め部材３の厚さが薄すぎてメタライズ層４ａとのロウ付け時にネジ止め部材３が変形してしまいボルト８が挿入できなかった。
【００４４】
以上の結果、ネジ止め部材３の肉厚は0.5〜2.5ｍｍであるのが好ましいことが判った。
【００４５】
なお、本発明は上記実施の形態の例および実施例に限定されるものではなく、本発明の要旨を逸脱しない範囲で変更、改良を施すことは何ら差し支えない。
【００４６】
【発明の効果】
本発明は、互いに対向配置されるとともにそれぞれ上下面を貫通する貫通孔が複数個形成された、金属からなる２つの円環状の電極部材と、両端面に凹部が形成されており、この凹部が貫通孔と同軸状となるようにして両端面が２つの電極部材の対向する主面にそれぞれ接合された、セラミックスからなる複数の円柱状の絶縁柱と、凹部に嵌入ロウ付けされた、金属からなる円筒状のネジ止め部材と、貫通孔に挿入されるとともにネジ止め部材にネジ込まれることによって、電極部材と絶縁柱とをネジ止めしているネジとを具備しており、凹部は、横断面形状が円形状であるとともに底面が凹んだ曲面とされており、その内面の全面にメタライズ層が形成されていることより、セラミックス製の絶縁柱に欠けなどの破損が発生し易いネジ加工を施すことなくネジ止めすることができるため、電極部材の対向する主面に絶縁柱を接合する際のネジ止め時に、絶縁柱にカケ，クラック等の破損が発生するのを有効に抑制することができる。
【００４７】
また、ネジ止め部材と絶縁柱とを接合するロウ材がネジ止めによる応力を有効に緩和することができるため、絶縁柱の破損を防止する効果をより向上させることができる。その結果、近時の核融合実験装置における中性粒子加熱装置に用いられる大型の絶縁支柱においても、絶縁柱にカケ，クラック等の破損が発生するのを有効に抑制することができる。
【００４８】
さらに、絶縁柱の両端面に形成された凹部は、横断面形状が円形状であるとともに底面が凹んだ曲面とされており、その内面の全面にメタライズ層が形成されているため、電極部材を加速電極等に接続して高い電圧を印加した際、ネジに生じる電荷は角部に集中することなく凹部内面の滑らかな曲面状のメタライズ層全面に分散させることができ、対向するネジ間での放電を有効に抑制することができる。
【００４９】
本発明の絶縁支柱は、ネジ止め部材の厚みが0.5乃至2.5ｍｍであることにより、絶縁柱にネジ止め部材をロウ付けする際に発生する熱膨張差による応力で絶縁柱にカケ，クラック等の破損が発生するのを防止できるとともに、ネジ止め部材が変形してネジ止めできなくなるのを防止できる。その結果、長期にわたってより正常に機能する絶縁支柱を提供することができる。
【図面の簡単な説明】
【図１】本発明の絶縁支柱における絶縁柱と電極部材との接合部について実施の形態の一例を示す部分拡大断面図である。
【図２】従来の絶縁支柱における絶縁柱と電極部材との接合部を示す部分拡大断面図である。
【図３】従来の絶縁支柱の斜視図である。
【符号の説明】
１：絶縁柱
２：電極部材
３：ネジ止め部材
４：凹部
４ａ：メタライズ層
５：ロウ材
８：ネジ[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an insulating column used in a portion to which a voltage is applied in order to accelerate charged particles and generate an accelerated beam in a vacuum vessel of a neutral particle heating device used in a nuclear fusion experimental device or the like. is there.
[0002]
[Prior art]
Conventionally, in a neutral particle heating apparatus used for a fusion experimental apparatus, an insulating support column is used as a part for applying a voltage for accelerating charged particles to generate an acceleration beam, that is, a support member such as an acceleration electrode. It has been. FIG. 3 is a perspective view showing the basic configuration of this insulating support. Moreover, the expanded sectional view of the junction part of the insulation pillar and electrode member in this insulation support | pillar is shown in FIG. 2 and 3, 11 is an insulating column, 12 is an electrode member connected to an accelerating electrode, etc., 17 is a screw hole, 18 is a screw such as a bolt, and these mainly constitute an insulating column.
[0003]
In the insulating column shown in FIG. 2, the insulating column 11 is made of a ceramic such as an aluminum oxide (Al ₂ O ₃ ) -based sintered body, and one or a plurality of screw holes 17 are formed on each end face thereof. The electrode member 12 and the screw 18 are made of a metal such as SUS.
[0004]
In order to join the insulating column 11 and the electrode member 12, a through hole is made in the electrode member 12 at a position corresponding to the screw hole 17 of the insulating column 11 in advance, and the electrode member 12 is applied to both end surfaces of the insulating column 11. The screw 18 is inserted through the through hole of the electrode member 12 and screwed into the screw hole 17 of the insulating column 11 and tightened to be mechanically joined. (For example, refer to Patent Document 1 below).
[0005]
Further, the screw hole 17 may be inserted with a helicate having a cylindrical shape made of a metal such as stainless steel (SUS) and screwed on the inner side surface and the outer side surface. Is screwed into the screw hole 17 of the insulating pillar 11 and the screw 18 is screwed into the threaded portion on the inner surface, so that the tightening of the screw 18 to the insulating pillar 11 can be made stronger.
[0006]
[Patent Document 1]
JP 2002-343292 A (page 8, FIG. 7)
[0007]
[Problems to be solved by the invention]
However, in the above-described conventional insulating column, since the screw hole 17 is directly screwed into the insulating column 11 made of ceramics as shown in FIG. 2, the screw is screwed into the screw hole 17 of the insulating column 11 and tightened. Thus, when the electrode member 12 is mechanically joined, stress such as tensile stress or shear stress is applied to the threaded portion of the screw hole 17 via the screw 18, and damage such as cracks or cracks is applied to the threaded portion of the screw hole 17. It was easy to occur.
[0008]
When the threaded portion of the screw hole 17 is damaged, the tightening strength of the screw 18 with respect to the insulating column 11 is reduced, and the insulating column 11 and the electrode member 12 cannot be firmly joined, and the function as the insulating column is achieved. There was a problem of disappearing.
[0009]
In particular, recently, the neutral particle heating device in the nuclear fusion experimental device has been enlarged, and along with that, the stress such as tensile stress and shear stress applied to the threaded portion of the screw hole 17 through the screw 18 has increased, Damage to the threaded portion of the insulating column 11 has come to be noticeable.
[0010]
In addition, when the electrode member 12 is connected to an acceleration electrode or the like and a high voltage is applied, a high voltage is also applied to the screw 18 screwed into both end faces of the insulating column 11, and the screw 18 is directed from the corner portion to the opposing screw 18. There is also a problem that discharge tends to occur.
[0011]
Accordingly, the present invention has been completed in view of the above problems, and its purpose is to prevent the insulating column from being damaged even if the electrode member is firmly screwed to the insulating column. An object of the present invention is to provide an insulating support that can increase the reliability of bonding and eliminate the discharge from a screw to function normally over a long period of time.
[0012]
[Means for Solving the Problems]
The insulating struts of the present invention are provided with two annular electrode members made of metal, each having a plurality of through-holes penetrating the upper and lower surfaces, and concave portions formed on both end surfaces, A plurality of cylindrical insulating columns made of ceramics, with both end surfaces joined to the opposing main surfaces of the two electrode members so that the recess is coaxial with the through-hole, and fitted into the recess A brazed cylindrical screw member made of metal, and a screw that is inserted into the through hole and screwed into the screw member, thereby screwing the electrode member and the insulating column. The concave portion has a circular cross-sectional shape and a curved surface with a concave bottom surface, and a metallized layer is formed on the entire inner surface.
[0013]
The present invention includes two annular electrode members made of metal, each having a plurality of through-holes penetrating the upper and lower surfaces, and concave portions formed on both end surfaces. A plurality of cylindrical insulating columns made of ceramics, both end surfaces of which are joined to the opposing main surfaces of the two electrode members so as to be coaxial with the through-hole, and a metal fitted into the recess and brazed. A cylindrical screw fixing member, and a screw that is inserted into the through hole and screwed into the screw fixing member to screw the electrode member and the insulating column, and the recess is transverse The surface of the surface is circular and the bottom surface is a curved surface with a concave surface. A metallized layer is formed on the entire inner surface, which makes it easy to cause damage such as chipping on ceramic insulating columns. Since it can be screwed without being applied, it is possible to effectively suppress the occurrence of breakage such as cracks and cracks in the insulating column when screwing the insulating column to the opposing main surface of the electrode member. it can.
[0014]
In addition, since the brazing material that joins the screwing member and the insulating column can effectively relieve the stress caused by screwing, the effect of preventing the insulating column from being damaged can be further improved. As a result, even in a large insulating support used in a neutral particle heating device in a recent nuclear fusion experimental device, it is possible to effectively suppress the occurrence of breakage such as cracks and cracks in the insulating post.
[0015]
Furthermore, the recesses formed on both end surfaces of the insulating pillar are circular with a circular cross section and a curved surface with a recessed bottom surface, and a metallized layer is formed on the entire inner surface. When a high voltage is applied by connecting to an accelerating electrode etc., the electric charge generated in the screw can be distributed over the smooth curved metallized layer on the inner surface of the recess without concentrating on the corner, and between the opposing screws Discharge can be effectively suppressed.
[0016]
In the insulating support of the present invention, preferably, the thickness of the screwing member is 0.5 to 2.5 mm.
[0017]
Since the thickness of the screwing member is 0.5 to 2.5 mm, the insulating column according to the present invention is free from cracks, cracks, etc. on the insulating column due to the stress due to the difference in thermal expansion that occurs when the screwing member is brazed to the insulating column. It is possible to prevent the occurrence of breakage and to prevent the screwing member from being deformed and unable to be screwed. As a result, it is possible to provide an insulating support column that functions more normally over a long period of time.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
The insulating column of the present invention will be described in detail below. FIG. 1 is a cross-sectional view of a junction between an insulating column and an electrode member in the insulating column of the present invention. In FIG. 1, 1 is an insulating column, 2 is an electrode member, 3 is a screwing member, 4 is a recess, and 5 is a brazing material.
[0019]
The insulating support column of the present invention has two annular electrode members 2 made of metal, which are arranged to face each other and each have a plurality of through holes penetrating the upper and lower surfaces, and recesses 4 are formed on both end surfaces. A plurality of cylindrical insulating pillars 1 made of ceramics, both end faces of which are joined to the opposing main surfaces of the two electrode members 2 so that the recess 4 is coaxial with the through-hole, A cylindrical screwing member 3 made of metal and brazed into the recess 4, and the electrode member 2 and the insulating column 1 are screwed by being inserted into the through hole and screwed into the screwing member 3. The concave portion 4 has a circular cross-sectional shape and a curved surface with a concave bottom surface, and a metallized layer 4a is formed on the entire inner surface.
[0020]
Insulative pedestal 1 of the present invention are those cross-sectional shape circular or square, polygonal such as a hexagon, of Al ₂ O ₃ quality sintered body or the like of the ceramic. On both end surfaces of the insulating pillar 1, a concave portion 4 having a concave bottom surface, for example, a spherical or parabolic curved surface, is formed, and molybdenum (Mo), manganese (Mn), tungsten (W ) And the like are formed.
[0021]
The metallized layer 4a acts as a base metal layer when the screwing member 3 is brazed, and when the electrode member 2 is connected to an acceleration electrode or the like and a high voltage is applied, charges generated in the screw 8 are applied to the corners. It also acts to disperse without concentrating. Such a metallized layer 4a is preferably coated on the surface with a metal such as nickel (Ni) or gold (Au) having excellent wettability with the brazing material 5 to a thickness of about 1 to 10 μm by plating. The screwing member 3 can be firmly brazed to the metallized layer 4a. Further, the opening of the recess 4 may be chamfered, whereby the meniscus of the brazing material 5 that joins the screwing member 3 and the recess 4 is improved, and the screwing member 3 is formed in the recess 4. Can be brazed firmly.
[0022]
The recesses 4 formed on both end surfaces of the insulating pillar 1 have a circular cross-sectional shape and a curved surface with a recessed bottom surface, and the metallized layer 4a is formed on the entire inner surface, so that the electrode member When a high voltage is applied by connecting 2 to an accelerating electrode or the like, the electric charge generated in the screw 8 can be dispersed over the entire surface of the smooth curved metallized layer 4a on the inner surface of the recess 4 without concentrating on the corners. The discharge between the screws 8 can be effectively suppressed.
[0023]
The electrode member 2 is an annular metal member in which a plurality of through-holes having a circular cross-sectional shape penetrating the upper and lower surfaces are formed in the annular portion at the same interval, and is made of SUS or the like. The electrode member 2 is joined to the insulating column 1 by inserting a screw 8 made of SUS or the like into the through hole and screwing the screw 8 into the screwing member 3.
[0024]
Preferably, the surface of the electrode member 2 should have small irregularities, and specifically, the arithmetic average roughness (Ra) of the surface should be Ra ≦ 0.4 μm. In this case, when a voltage is applied to the electrode member 2 to accelerate charged particles such as electrons, generation of minute discharge between the electrode members 2 can be effectively suppressed, and a high voltage can be stably applied. The number of through holes formed in the electrode member 2 is about 4 to 6.
[0025]
The screwing member 3 is made of a cylindrical metal member whose inner peripheral surface is threaded, and is fitted into the recess 4 of the insulating column 1 so as to be soldered such as silver (Ag) brazing or Ag-copper (Cu) brazing. It is brazed with the material 5. For example, the screwing member 3 is preferably made of a material having a coefficient of thermal expansion close to that of the ceramic of the insulating column 1 such as an Fe—Ni—Co alloy, and heat is applied when the screwing member 3 is brazed to the insulating column 1. It is possible to suppress the occurrence of an expansion difference and prevent the insulating pillar 1 from being damaged such as a crack or the screwing member 3 from being deformed.
[0026]
Also, the brazing material 5 for joining the screwing member 3 and the metallized layer 4a on the inner surface of the recess 4 is preferably attached to the entire surface of the metallized layer 4a. As a result, the adhesion between the brazing material 5 and the metallized layer 4a can be further improved, and the occurrence of discharge in the brazing material 5 protruding between the lower end surface of the screwing member 3 and the metallized layer 4a. It can be effectively suppressed.
[0027]
Since the screwing member 3 has a cylindrical shape, the brazing material 5 in the metallized layer 4a below the screwing member 3 is brazed to the metallized layer 4a of the recess 4 with the brazing material 5 after the screwing member 3 is brazed. The state of the flow can be confirmed, and it can be visually confirmed whether or not the entire joining surface of the screwing member 3 and the recess 4 can be brazed.
[0028]
Preferably, the thickness of the screwing member 3 is 0.5 to 2.5 mm. With this configuration, the insulating column 1 is subjected to stress due to a difference in thermal expansion generated when the screwing member 3 is brazed to the insulating column 1. It is possible to prevent breakage such as cracks and cracks from occurring, and it is possible to prevent the screwing member 3 from being deformed to prevent the screw 8 from being screwed. If the thickness is smaller than 0.5 mm, it is difficult to screw the screw 8 by deforming due to a difference in thermal expansion when the screwing member 3 is brazed to the insulating column 1. On the other hand, when the thickness exceeds 2.5 mm, a large stress due to a difference in thermal expansion occurs between the screwing member 3 and the insulating column 1 during brazing, and the insulating column 1 is damaged due to this stress. It becomes easy.
[0029]
The thickness of the screwing member 3 is the distance between the apex of the thread formed on the inner peripheral surface of the screwing member 3 and the outer side surface of the screwing member 3.
[0030]
Moreover, as for the screwing member 3, it is more preferable that the screw process formed in the internal peripheral surface has not reached the lower end part. As a result, there is no pointed portion where charge is likely to concentrate around the lower end of the screwing member 3, and it is possible to more effectively suppress discharge from occurring in the screwing member 3.
[0031]
The screw 8 has a flat bottom and is screwed into the screwing member 3 so that the screw bottom of the screw 8 and the lower end of the screwing member 3 are flush with each other. It is good. Thereby, it can suppress more effectively that an electric charge concentrates on the screw bottom of the screw 8, and the lower end part of the screwing member 3, and suppresses that a discharge arises in the screw 8 or the screwing member 3 more effectively. be able to.
[0032]
【Example】
Examples of the present invention will be described below.
[0033]
The thing of the structure shown in FIG. 1 was produced as follows.
[0034]
A cylindrical insulating column 1 having a diameter of 80 mm and a length of 290 mm made of an Al ₂ O ₃ sintered material having a purity of 99% by weight was prepared. Two recesses 4 each having a diameter of 15 mm and a depth of 26 mm were provided on both end faces of the insulating pillar 1. The bottom corner portion of the recess 4 is an arcuate curved surface having a radius of 5 mm, and the opening is chamfered by 3 mm.
[0035]
A metal paste containing Mo, Mn, and silica (SiO ₂ ) in a proportion of 89% by weight, 6% by weight, and 5% by weight on the entire surface of both end surfaces of the insulating pillar 1, the inner surface of the recess 4 and the entire surface of the chamfered portion, respectively. Was printed and applied to a thickness of 10 μm, dried, and fired at 1400 ° C. in a humidified forming gas. Thus, the metallized layer 4a made of the Mo—Mn alloy was deposited on the entire surface of both end faces of the insulating pillar 1, the inner surface of the recess 4 and the entire chamfered portion. Thereafter, a Ni plating layer was deposited on the metallized layer 4a to a thickness of about 2 μm by electrolytic plating.
[0036]
Next, the recess 4 of the insulating pillar 1 is threaded with M10 (according to JIS B0123) over the entire length of the inner diameter of 15 mm (thus the thickness of the screwing member 3 is 2.5 mm). A screw member 3 made of a Fe-Ni-Co alloy with a 21 mm-thick cylindrical outer surface and Ra of 6.3 μm is fitted, and the outer surface of the screw member 3 is brazed and fixed to the metallized layer 4 a with a brazing material 5. did. At this time, a brazing material 5 made of a wire-shaped Ag—Cu alloy having a diameter of 1 mm is installed in a ring shape having a diameter of 15 mm between the chamfered portion of the recess 4 of the insulating pillar 1 and the screwing member 3. It was joined by heating to 820 ° C. Thus, the manufactured sample was designated as sample A1.
[0037]
Furthermore, sample A2 (the thickness of the screwing member 3 is 2 mm) with the threaded portion inside the screwing member 3 being M11, sample A3 (the thickness of the screwing member 3 is 1.5 mm) with the threaded portion being M12, Sample A4 (the thickness of the screwing member 3 is 1 mm) having a threaded portion M13 and sample A5 (the thickness of the screwing member 3 is 0.5 mm) having a threaded portion M14 were prepared.
[0038]
As a comparative example, the recess 4 of the same insulating column 1 as the sample A1 is threaded with M9 (according to JIS B0123) with an outer diameter of 15 mm over the entire inner length (thus the thickness of the screwing member 3 is 3 mm). The screw member 3 made of an Fe-Ni-Co alloy having a cylindrical shape with a length of 21 mm and an outer surface Ra of 6.3 μm is fitted, and the outer surface of the screw member 3 is brazed to the metallized layer 4a. And fixed with brazing. The joining method was the same as that of sample A1. The product thus produced was designated as Sample B.
[0039]
Further, as a comparative example, the concave portion 4 of the same insulating column 1 as the sample A1 has an outer diameter of 14.8 mm and is threaded with M14 (according to JIS B0123) over the entire inner length (the thickness of the screwing member 3 thereby. The screw fixing member 3 made of an Fe—Ni—Co alloy having a cylindrical shape with a length of 21 mm and an outer surface Ra of 6.3 μm is fitted into the metallized layer 4a. The side surfaces were fixed with brazing material 5 by brazing. The joining method was the same as that of sample A1. The product thus produced was designated as Sample C.
[0040]
For each of Samples A1 to A5, B, and C, a bolt 8 suitable for the threaded portion of the screwing member 3 was inserted, and a test was performed by applying a torque of 65 N · m.
[0041]
Samples A1 to A5 did not break even at 65 N · m torque.
[0042]
In sample B, cracks starting from the recesses 4 of the insulating pillar 1 occurred during brazing.
[0043]
In sample C, the screwing member 3 was too thin, and the screwing member 3 was deformed during brazing with the metallized layer 4a, so that the bolt 8 could not be inserted.
[0044]
As a result, it was found that the thickness of the screwing member 3 is preferably 0.5 to 2.5 mm.
[0045]
It should be noted that the present invention is not limited to the examples and examples of the above-described embodiment, and changes and modifications can be made without departing from the scope of the present invention.
[0046]
【The invention's effect】
The present invention includes two annular electrode members made of metal, each having a plurality of through-holes penetrating the upper and lower surfaces, and concave portions formed on both end surfaces. A plurality of cylindrical insulating columns made of ceramics, both end surfaces of which are joined to the opposing main surfaces of the two electrode members so as to be coaxial with the through-hole, and a metal fitted into the recess and brazed. A cylindrical screw fixing member, and a screw that is inserted into the through hole and screwed into the screw fixing member to screw the electrode member and the insulating column, and the recess is transverse The surface of the surface is circular and the bottom surface is a curved surface with a concave surface. A metallized layer is formed on the entire inner surface, which makes it easy to cause damage such as chipping on ceramic insulating columns. Since it can be screwed without being applied, it is possible to effectively suppress the occurrence of breakage such as cracks and cracks in the insulating column when screwing the insulating column to the opposing main surface of the electrode member. it can.
[0047]
In addition, since the brazing material that joins the screwing member and the insulating column can effectively relieve the stress caused by screwing, the effect of preventing the insulating column from being damaged can be further improved. As a result, even in a large insulating support used in a neutral particle heating device in a recent nuclear fusion experimental device, it is possible to effectively suppress the occurrence of breakage such as cracks and cracks in the insulating post.
[0048]
Furthermore, the recesses formed on both end surfaces of the insulating pillar are circular with a circular cross section and a curved surface with a recessed bottom surface, and a metallized layer is formed on the entire inner surface. When a high voltage is applied by connecting to an accelerating electrode etc., the electric charge generated in the screw can be distributed over the smooth curved metallized layer on the inner surface of the recess without concentrating on the corner, and between the opposing screws Discharge can be effectively suppressed.
[0049]
Since the thickness of the screwing member is 0.5 to 2.5 mm, the insulating column according to the present invention is free from cracks, cracks, etc. on the insulating column due to the stress due to the difference in thermal expansion that occurs when the screwing member is brazed to the insulating column. It is possible to prevent the occurrence of breakage and to prevent the screwing member from being deformed and unable to be screwed. As a result, it is possible to provide an insulating support column that functions more normally over a long period of time.
[Brief description of the drawings]
FIG. 1 is a partially enlarged cross-sectional view showing an example of an embodiment of a junction between an insulating column and an electrode member in an insulating column of the present invention.
FIG. 2 is a partially enlarged cross-sectional view showing a joint portion between an insulating column and an electrode member in a conventional insulating column.
FIG. 3 is a perspective view of a conventional insulating column.
[Explanation of symbols]
1: Insulating column 2: Electrode member 3: Screw fixing member 4: Recess 4a: Metallized layer 5: Brazing material 8: Screw

Claims

互いに対向配置されるとともにそれぞれ上下面を貫通する貫通孔が複数個形成された、金属からなる２つの円環状の電極部材と、両端面に凹部が形成されており、該凹部が前記貫通孔と同軸状となるようにして前記両端面が前記２つの電極部材の対向する主面にそれぞれ接合された、セラミックスからなる複数の円柱状の絶縁柱と、前記凹部に嵌入ロウ付けされた、金属からなる円筒状のネジ止め部材と、前記貫通孔に挿入されるとともに前記ネジ止め部材にネジ込まれることによって、前記電極部材と前記絶縁柱とをネジ止めしているネジとを具備しており、前記凹部は、横断面形状が円形状であるとともに底面が凹んだ曲面とされており、その内面の全面にメタライズ層が形成されていることを特徴とする絶縁支柱。Two annular electrode members made of metal, which are arranged to face each other and each have a plurality of through holes penetrating the upper and lower surfaces, and concave portions are formed on both end surfaces, and the concave portions are connected to the through holes. A plurality of cylindrical insulating columns made of ceramics, both end surfaces of which are joined to the opposing main surfaces of the two electrode members so as to be coaxial, and a metal fitted into the recess and brazed. A cylindrical screwing member, and a screw screwed into the electrode member and the insulating column by being inserted into the through-hole and screwed into the screwing member, Insulating struts characterized in that the recess has a circular cross section and a curved surface with a recessed bottom surface, and a metallized layer is formed on the entire inner surface.

前記ネジ止め部材の厚みが０．５乃至２．５ｍｍであることを特徴とする請求項１記載の絶縁支柱。2. The insulating column according to claim 1, wherein the screwing member has a thickness of 0.5 to 2.5 mm.