JP4067927B2

JP4067927B2 - Vacuum valve

Info

Publication number: JP4067927B2
Application number: JP2002278425A
Authority: JP
Inventors: 徹上川路
Original assignee: Toshiba Corp
Current assignee: Toshiba Corp
Priority date: 2002-09-25
Filing date: 2002-09-25
Publication date: 2008-03-26
Anticipated expiration: 2022-09-25
Also published as: JP2004119091A

Description

【０００１】
【発明の属する技術分野】
本発明は、真空絶縁容器内の電界強度を抑制した真空バルブに関する。
【０００２】
【従来の技術】
周知のように、真空遮断器に用いる真空バルブは、約１０^−２Ｐａ以下の高真空中で一対の電極を接離することにより、真空の持つ優れた消弧性、絶縁性を利用して電流遮断を行なうものである。
【０００３】
図１１にその代表的な構造を示す真空バルブは、例えばセラミックスからなる筒状の真空絶縁容器１が中間リング２を介して連結され、前記真空絶縁容器１の両端開口部が金属製で環状の接合部材３を介して固定側端板４および可動側端板５でそれぞれ密封されている。そして、前記固定側端板４には、固定通電軸６が貫通固定され、この固定通電軸６の前記真空絶縁容器１内の端面部に固定電極７が固着されている。
【０００４】
また、前記固定電極７と対向して、可動電極８が図示しない操作機構に連結された可動通電軸９の前記真空絶縁容器１内の端面部に固着されている。そして、前記可動通電軸９と前記可動側端板５との中央開口部は、ベローズ１０により気密が保持され、これにより真空を保って前記可動通電軸９を動作させることができるようになっている。
【０００５】
なお、アークシールド１１が取付金具１２を介して前記中間リング２に固設され、前記電極７、８から飛散する金属蒸気や金属溶融片が前記絶縁容器１の内面に付着し、沿面の絶縁性能が低下するのを防止している。
【０００６】
以上述べたような一般的な真空バルブを、高電圧用として用いる場合には、前記真空絶縁容器１の内面の沿面絶縁特性を向上させる必要がある。そこで、前記真空絶縁容器１の全長を維持しながら沿面距離を増大させる方法が知られている（例えば、特許文献１参照。）。これは、図１２に示すように、前記固定通電軸６に例えばセラミックからなる環状の絶縁円板１３を貫通させ、この絶縁円板１３の沿面距離を加算して真空バルブ全体の沿面距離を増大させるものである。
【０００７】
そして、前記絶縁円板１３の内径側の側面と前記固定通電軸６の間は、金属製で環状の円板１４で接合され、また、外径側の側面と前記真空絶縁容器１の端面の間は、金属製で円弧状の接合部材１５で接合されている。これらの接合は、それぞれの前記真空絶縁容器１端面と前記絶縁円板１３側面にメタライズ層１ａ、１３ａ、１３ｂを形成させて行われている。
【０００８】
このメタライズ層１ａ、１３ａ、１３ｂは、セラミックスと金属とを銀ろう付けにより接合するときに、予めセラミックスのろう付け部近傍に金属化処理を施すものである。例えば、アルミナセラミックスの場合には、モリブデンとマンガンの微粉末を塗布しておいて高温加熱し、拡散相を形成させ、その上にニッケルなどの金属層をメッキにより形成するものである。
【０００９】
【特許文献１】
特開平１１−２０３９９６号公報（第５頁、図９）
【００１０】
【発明が解決しようとする課題】
上述のような構成の真空バルブによれば、金属層の前記メタライズ層１ａ、１３ａ、１３ｂの真空側の部位は、絶縁物製の前記真空絶縁容器１と前記絶縁円板１３と、真空の絶縁媒体の３つの境界となり、金属／絶縁物／絶縁媒体が結合される、いわゆるトリプルジャンクションとなり電界強度が上昇する。特に、前記絶縁円板１３では、前記メタライズ層１３ａ、１３ｂの真空側の部位が前記電極７の方向に向かって形成され、更に前記真空絶縁容器１より沿面距離が短いので電界強度の上昇が極めて大きくなる。また、真空中の絶縁破壊は電界依存性を示すため、真空バルブに高電圧が印加されると、前記トリプルジャンクション部から放電が始まり、前記絶縁円板１３の真空バルブ内面で絶縁破壊を起こす問題があった。
【００１１】
従って、真空バルブを高電圧用として用いるには、前記真空絶縁容器１や前記絶縁円板１３の沿面距離を増大させなくてはならなかった。これは、最近の趨勢である縮小化に逆行するものである。
【００１２】
本発明の目的は、上記に鑑みなされたもので、絶縁破壊の起点となるトリプルジャンクションによる電界強度の上昇を抑制した真空バルブを提供することにある。
【００１６】
【課題を解決するための手段】
本発明の真空バルブは、筒状の真空絶縁容器内に設けた互いに接離自在の一対の電極と、この電極の一方が固着された固定通電軸と、前記固定通電軸が貫通され、且つ前記真空絶縁容器の一側の開口部に小径部が前記電極に向かって設けられた環状の固定側絶縁円錐板と、前記固定側絶縁円錐板の外気側表面における小径側と大径側にそれぞれ施された小径側および大径側のメタライズ層と、前記固定側絶縁円錐板の小径側と前記小径側のメタライズ層を介して一端が接合され、他端が前記固定側通電軸に接合された断面円弧状の環状の第４の接合部材と、前記固定側絶縁円錐板の大径側と前記大径側のメタライズ層を介して一端が接合され、他端が前記真空絶縁容器の一側に接合された断面円弧状の環状の第５の接合部材と、前記電極の他方が固着され、且つベローズの一端が固着された可動通電軸と、前記可動通電軸が貫通され、且つ前記真空絶縁容器の他側の開口部に小径部が前記電極に向かって設けられた環状の可動側絶縁円錐板と、前記可動側絶縁円錐板の外気側表面における小径側と大径側にそれぞれ施された小径側および大径側のメタライズ層と、前記可動側絶縁円錐板の大径側と前記大径側のメタライズ層を介して一端が接合され、他端が前記真空絶縁容器の他側に接合された断面円弧状の環状の第６の接合部材とを有し、前記可動側絶縁円錐板の円錐状の内側に前記ベローズを設け、且つ前記可動側絶縁円錐板の小径側と前記小径側のメタライズ層を介して前記ベローズの自由端部とを接合したことを特徴とする。
【００１７】
このように本発明の構成によれば、前記真空絶縁容器の両端開口部に設ける前記絶縁円錐板の前記メタライズ層を外気側表面に設け、前記第４の接合部材、前記第５の接合部材、前記第６の接合部材および前記ベローズ自由端部により、前記メタライズ層における真空側に位置する部位の電界緩和を図るため、金属／絶縁物／絶縁媒体の３つの境界が結合されるトリプルジャンクションでの電界強度の上昇が抑えられる。
【００１８】
従って、真空側で電界強度を充分に抑えられるので、電界依存性を示す破壊電圧特性が向上し、真空バルブの高電圧化を図ることができる。
【００１９】
【発明の実施の形態】
以下、本発明の実施の形態について図面を参照して説明する。なお、各図において、従来と同様の構成部分については同一符号を付した。
【００２０】
（第１の実施の形態）
先ず、本発明の第１の実施の形態に係る真空バルブを図１を参照して説明する。図１は、本実施の形態に係る真空バルブの縦断面図である。
【００２１】
図１に示すように、真空バルブは、例えばセラミックからなる筒状の真空絶縁容器１が中間リング２を介して連結され、前記真空絶縁容器１の両端開口部に例えば前記真空絶縁容器１と同種材料のセラミックからなる環状の固定側絶縁円板１６および環状の可動側絶縁円板１７がそれぞれ設けられている。
【００２２】
そして、真空バルブの固定側では、環状の前記固定側絶縁円板１６に固定通電軸６が貫通され、金属製で断面円弧状の環状の第１の接合部材１８により、前記固定通電軸６の軸周囲と前記固定側絶縁円板１６の内径側で且つ外気側表面間が接合される。また、前記固定側絶縁円板１６の外径側で且つ外気側表面と前記真空絶縁容器１端面間は、金属製で断面円弧状の環状の第２の接合部材１９で接合される。
【００２３】
一方、可動側では、環状の前記可動側絶縁円板１７の外径側で且つ外気側表面と前記真空絶縁容器１端面間が、金属製で断面円弧状の環状の第３の接合部材２０で接合される。また、可動通電軸９の軸周囲に一端が接合されたベローズ２１の自由端部２１ａは、半径方向の外側に広がった環状に構成され、その自由端部２１ａが前記可動側絶縁円板１７の内径側で且つ外気側表面に接合される。
【００２４】
これら前記真空絶縁容器１と、環状の前記固定側絶縁円板１６、前記可動側絶縁円板１７の接合面となる部位には、それぞれ環状にメタライズ層１ａ、１６ａ、１６ｂ、１７ａ、１７ｂが施される。これらメタライズ層１ａ、１６ａ、１６ｂ、１７ａ、１７ｂに、前記第１の接合部材１８、前記第２の接合部材１９、前記第３の接合部材２０および前記ベローズ２１の自由端部２１ａが銀ろう付けにより接合される。
【００２５】
また、前記固定側絶縁円板１６、前記可動側絶縁円板１７の前記メタライズ層１６ａ、１６ｂ、１７ａ、１７ｂにおける真空側に位置する部位は、前記第１の接合部材１８、前記第２の接合部材１９、前記第３の接合部材２０および前記ベローズ２１の自由端部２１ａを円弧状とした曲率部の内側に位置させている。
【００２６】
なお、前記固定通電軸６と前記可動通電軸９の前記真空絶縁容器１内には、それぞれ固定電極７と可動電極８が対向して固着され、また、前記可動通電軸９には図示しない操作機構が連結され、前記電極７、８の接離が行われるものである。更に、アークシールド１１が取付金具１２を介して前記中間リング２に固設され、前記電極７、８から飛散する金属蒸気や金属溶融片が前記絶縁容器１の内面に付着し、沿面の絶縁性能の低下を防止している。
【００２７】
上記第１の実施の形態によれば、環状の前記固定側絶縁円板１６、前記可動側絶縁円板１７における前記夫々メタライズ層１６ａ、１６ｂ、１７ａ、１７ｂの真空側に位置する部位を、前記第１の接合部材１８、前記第２の接合部材１９、前記第３の接合部材２０および前記ベローズ２１の自由端部２１ａの夫々円弧状とした曲率部の内側に位置させている。このため、金属層の前記メタライズ層１６ａ、１６ｂ、１７ａ、１７ｂの真空側に位置する部位の、絶縁物製の前記固定側絶縁円板１６、前記可動側絶縁円板１７と、真空の絶縁媒体の３つの境界となるトリプルジャンクションでの電界強度の上昇が抑えられる。
【００２８】
従って、電界依存性を示す破壊電圧特性が向上し、真空バルブの高電圧化を図ることができる。
【００２９】
なお、上記第１の実施の形態では、環状の固定側絶縁円板１６を用いたが、図２に示すように、真空側に環状の突出部２２ｃを有した環状の固定側絶縁円板２２を用いてもよい。この構成によっても、環状のメタライズ層２２ａ、２２ｂにおける真空側に位置する部位が、第１の接合部材１８、第２の接合部材１９の曲率部の内側に位置するため、トリプルジャンクションでの電界強度の上昇が抑えられる。また、真空側の沿面距離を増加させることができる。
【００３０】
なお、可動側絶縁円板においても、真空側に同様の突出部を設ければ、電界強度の上昇を抑えられ、また、真空側の沿面距離を増加させることができる。
【００３１】
（第２の実施の形態）
次に、本発明の第２の実施の形態に係る真空バルブを図３を参照して説明する。図３は、本実施の形態に係る真空バルブの縦断面図である。なお、同図において、第１の実施の形態と同一構成部分には、同一符号を付して詳しい説明は省略する。
【００３２】
図３に示すように、真空バルブは、例えばセラミックからなる筒状の真空絶縁容器１が中間リング２を介して連結され、前記真空絶縁容器１の両端開口部に、前記真空絶縁容器１と同種材料の例えばセラミックからなる環状の固定側絶縁円錐板２３および環状の可動側絶縁円錐板２４が設けられる。また、この固定側絶縁円錐板２３と可動側絶縁円錐板２４の小径部は、それぞれ固定電極７、可動電極８の方向に向かって設けられる。
【００３３】
そして、固定側では、環状の前記固定側絶縁円錐板２３の小径部に固定通電軸６が貫通され、金属製で断面円弧状に形成された環状の第４の接合部材２５により、前記固定通電軸６の軸周囲と前記小径部の外気側表面の間が接合される。また、前記固定側絶縁円錐板２３の大径部の外気側表面と前記真空絶縁容器１の端面の間が金属製で断面円弧状に形成された環状の第５の接合部材２６で接合される。
【００３４】
一方、可動側では、前記可動側絶縁円錐板２４の大径部の外気側表面と前記真空絶縁容器１の端面間が金属製で断面円弧状に形成された環状の第６の接合部材２７で接合される。また、この可動側絶縁円錐板２４の円錐状の内側に設けられ、一方の端部が可動通電軸９に接合されたベローズ２８の自由端部２８ａが、前記小径部の外気側表面に接合される。
【００３５】
これら前記真空絶縁容器１、前記固定側絶縁円錐板２３、前記可動側絶縁円錐板２４の接合面となる部位には、それぞれ環状にメタライズ層１ａ、２３ａ、２３ｂ、２４ａ、２４ｂが施される。これらメタライズ層１ａ、２３ａ、２３ｂ、２４ａ、２４ｂに、前記第４の接合部材２５、第５の接合部材２６、前記第６の接合部材２７および前記ベローズ２８の自由端部２８ａが銀ろう付けにより接合される。
【００３６】
そして、前記固定側絶縁円錐板２３、前記可動側絶縁円錐板２４の前記メタライズ層２３ａ、２３ｂ、２４ｂにおける真空側に位置する部位は、いずれも前記第４の接合部材２５、前記第５の接合部材２６、前記第６の接合部材２７の曲率部の内側に位置している。また、前記メタライズ層２４ａにおける真空側に位置する部位は、前記ベローズ２８の自由端部２８ａが曲率部の内側部分に近接して位置している。
【００３７】
上記第２の実施の形態によれば、前記夫々メタライズ層２３ａ、２３ｂ、２４ｂの真空側に位置する部位が、前記第４の接合部材２５、第５の接合部材２６、第６の接合部材２７の曲率部の内側に設けられているため、トリプルジャンクションでの電界強度の上昇が抑えられる。また、前記メタライズ層２４ａの真空側に位置する部位は、前記ベローズ２８の自由端部２８ａが曲率部の内側部分に近接しているため、トリプルジャンクションでの電界強度の上昇が抑えられる。
【００３８】
従って、電界依存性を示す破壊電圧特性が向上し、真空バルブの高電圧化を図ることができる。
【００３９】
また、前記固定側絶縁円錐板２３や前記可動側絶縁円錐板２４は、第１の実施の形態の固定側絶縁円板１６や可動側絶縁円板１７に比べて沿面距離が増加する。
【００４０】
更に、前記固定側絶縁円錐板２３が前記固定電極７に向かって設けられており、前記固定通電軸６が真空中で断熱されている部分を短くできるので、放熱特性が向上する。
【００４１】
なお、図４のように、上記第２の実施の形態に用いた前記固定側絶縁円錐板２３と可動側絶縁円錐板２４の前記電極７、８側に、皿状のシールドリング２９、３０を前記固定通電軸６と前記可動通電軸９に固設してもよい。
【００４２】
これにより、前記メタライズ層２３ａ、２４ａの真空側に位置する部位は、前記シールドリング２９、３０にそれぞれ覆われるので、トリプルジャンクションによる電界強度の上昇を抑制できる。
【００４３】
また、前記シールドリング２９、３０で、前記電極７、８の間で電流遮断したときに発生する金属蒸気が前記絶縁円錐板２３、２４の表面に付着することを防止できる。
【００４４】
更に、上記第２の実施の形態では、可動側において、前記可動側絶縁円錐板２４の円錐状の内側に前記ベローズ２８を設けたが、図５のように、前記可動側絶縁円錐板２４と前記可動電極８の間にベローズ３１を設けてもよい。この場合においても、前記ベローズ３１の自由端部３１ａは、前記可動側絶縁円錐板２４の小径部の外気側表面に設けたメタライズ層２４ａに接合されている。
【００４５】
これにより、上記第２の実施の形態の効果の他に、前記可動通電軸９が真空中で断熱されている部分が短くなるため、放熱特性が向上する。また、前記ベローズ３１が前記真空絶縁容器１の内側に設けられているので、外力による損傷を防止することができる。
【００４６】
（他の実施の形態）
本発明の他の実施の形態に係る真空バルブを図６乃至図１０を参照して説明する。図６は、本実施の形態に係る真空バルブの固定側の縦断面図、図７は、本実施の形態に係る真空バルブの固定側の縦断面図、図８は、本実施の形態に係る真空バルブの縦断面図、図９は、本実施の形態に係る真空バルブの固定側の縦断面図、図１０は、本実施の形態に係る真空バルブの固定側の縦断面図である。なお、図６乃至図１０において、第１の実施の形態と同一構成部分には、同一符号を付して詳しい説明は省略する。
【００４７】
先ず、本発明の他の実施の形態で電界緩和を図る構成を説明する。図６に示すように、真空バルブの固定側では、固定通電軸６を貫通させた環状の固定側絶縁円板１６の内径側の真空側表面に環状のメタライズ層１６ｃを形成させる。そして、このメタライズ層１６ｃの外径より大きい外周径を有する金属製で断面Ｃ字状の環状の第７の接合部材３２の一端が、前記メタライズ層１６ｃを介して例えば銀ろう付けで接合され、また、他端が前記固定通電軸６の軸周囲に接合される。
【００４８】
前記固定側絶縁円板１６の外径側の側面と真空絶縁容器１の端面には、それぞれメタライズ層１６ｄ、１ａが設けられ、両者間に金属製で断面円弧状の環状の第８の接合部材３３が例えば銀ろう付けで接合される。そして、前記第８の接合部材３３の前記固定側絶縁円板１６のメタライズ層１６ｄ側近傍には、先端が前記固定通電軸６の方向に向かって湾曲した環状のシールドリング３４が固設される。
【００４９】
このように、前記固定側絶縁円板１６の内径側の前記メタライズ層１６ｃが真空側に位置する部位は、前記第７の接合部材３２が曲率している外周の曲面に近接することになる。また、外径側の前記メタライズ層１６ｄの真空側に位置する部位は、前記シールドリング３４の湾曲した曲率部の内側に覆われている。
【００５０】
上記の実施の形態によれば、前記メタライズ層１６ｃの真空側に位置する部位は、前記第７の接合部材３２に近接しているため、トリプルジャンクションでの電界強度の上昇が抑えられる。また、前記メタライズ層１６ｄの真空側に位置する部位は、前記シールドリング３４の曲率部の内側に覆われるため、トリプルジャンクションでの電界強度の上昇が抑えられる。
【００５１】
なお、上記の実施の形態で用いた前記固定通電軸６において、この固定通電軸６が前記固定側絶縁円板１６を貫通した外気側の軸周囲に、図７のように、突出した環状のシールドリング３５を設けてもよい。このシールドリング３５は、真空バルブ組立て後に前記固定通電軸６に装着する。これにより、前記メタライズ層１６ｃの全体が真空側の前記第７の接合部材３２と外気側の前記シールドリング３５に挟装され、トリプルジャンクションでの電界強度の上昇が抑えられる。
【００５２】
なお、上記の他の実施の形態では、固定側について述べたが、可動側においても上記と同様の前記シールドリング３４を設けることにより、トリプルジャンクションによる電界強度の上昇を抑制することができる。
【００５３】
次に、本発明の更に他の実施の形態で沿面距離の増加を図る構成を説明する。図８に示すように、真空バルブは、例えばセラミックからなる筒状の真空絶縁容器１が中間リング２を介して連結され、前記真空絶縁容器１の両端開口部内に、例えばセラミックからなる固定側絶縁円筒３６と可動側絶縁円筒３７を前記真空絶縁容器１と同軸に設ける。
【００５４】
そして、金属製で断面Ｕ字状の環状の第９の接合部材３８の一端が、前記真空絶縁容器１の一側に接合され、また、他端が前記固定側絶縁円筒３６の一側に接合される。更に、金属製で断面Ｕ字状の環状の第１０の接合部材３９の一端が、前記固定側絶縁円筒３６の他側に接合され、また、他端が前記固定通電軸６の軸周囲に接合される。
【００５５】
一方、可動側においては、金属製で断面Ｕ字状の環状の第１１の接合部材４１の一端が前記真空絶縁容器１の他側に接合され、また、他端が前記可動側絶縁円筒３７の一側に接合される。更に、一端を前記可動通電軸９に接合されたベローズ４０の自由端部４０ａは、半径方向の外側に広がって、前記可動側絶縁円筒３７の他側の端部に接合され、前記真空絶縁容器１内が高真空に保たれている。
【００５６】
上記の実施の形態によれば、前記固定側絶縁円筒３６と前記可動側絶縁円筒３７により真空バルブの沿面距離が増加する。
【００５７】
なお、図９のように、前記固定通電軸６が前記第９の接合部材３８を貫通する部分に絶縁層４２を設ければ、前記固定通電軸６と前記第９の接合部材３８の間の絶縁耐力を向上させることができる。
【００５８】
更に、図１０のように、前記固定通電軸６に設けた絶縁層４２のほかに、前記第９の接合部材３８の表面に絶縁層４３を設ければ、前記固定通電軸６と前記第９の接合部材３８の間の絶縁耐力が更に向上する。なお、可動側でも同様に、前記第１１の接合部材４１に絶縁層を設ければ、前記ベローズ４０との絶縁耐力を向上させることができる。
【００５９】
本発明は、上記の実施の形態に限定されるものではなく、発明の要旨を逸脱しない範囲で、種々変形して実施することができる。例えば、第１および第２の実施の形態では、真空絶縁容器１、固定側絶縁円板１６、２２、可動側絶縁円板１７、固定側絶縁円錐板２３、可動側絶縁円錐板２４の全てを同種材料としている。これらを比誘電率の異なる異種材料として、前記真空絶縁容器１より、前記固定側絶縁円板１６、前記可動側絶縁円板１７、前記固定側絶縁円錐板２３、前記可動側絶縁円錐板２４の方の比誘電率を小さくしてもよい。
【００６０】
これにより、真空バルブを真空遮断器に組込んだとき、真空遮断器の取付け板などの対地間との静電容量結合による電位分担を改善できる。即ち、前記第２の接合部材１９、前記第３の接合部材２０、前記第５の接合部材２６、前記第６の接合部材２７および前記第８の接合部材３３の電位は、対地側の固有容量が大きく接地電位側へ変位するが、この変位の程度を抑制することができる。
【００６１】
【発明の効果】
以上述べたように、本発明によれば、真空絶縁容器の両端開口部に設けられる絶縁板の外気側表面にメタライズ層を施し、このメタライズ層を介して接合部材を接合することにより、真空側に位置する部位の金属層のメタライズ層と、絶縁物製の絶縁板と、真空の絶縁媒体の３つの境界が結合されるトリプルジャンクションでの電界強度の上昇を抑制できるので、電界依存性を示す破壊電圧特性が向上し、真空バルブの高電圧化を図ることができる。
【図面の簡単な説明】
【図１】本発明の第１の実施の形態に係る真空バルブを示す縦断面図。
【図２】本発明の第１の実施の形態の変形例に係る真空バルブを示す固定側の要部縦断面図。
【図３】本発明の第２の実施の形態に係る真空バルブを示す縦断面図。
【図４】本発明の第２の実施の形態の変形例に係る真空バルブを示す縦断面図。
【図５】本発明の第２の実施の形態の変形例に係る真空バルブを示す縦断面図。
【図６】本発明のその他の実施の形態に係る真空バルブを示す固定側の要部縦断面図。
【図７】本発明のその他の実施の形態に係る真空バルブを示す固定側の要部縦断面図。
【図８】本発明のその他の実施の形態に係る真空バルブを示す縦断面図。
【図９】本発明のその他の実施の形態に係る真空バルブを示す固定側の要部縦断面図。
【図１０】本発明のその他の実施の形態に係る真空バルブを示す固定側の要部縦断面図。
【図１１】従来の真空バルブを示す縦断面図。
【図１２】従来の真空バルブを示す固定側の要部縦断面図。
【符号の説明】
１真空絶縁容器
１ａ、１３ａ、１３ｂ、１６ａ、１６ｂ、１６ｃ、１６ｄ、１７ａ、１７ｂ、２２ａ、２２ｂ、２３ａ、２３ｂ、２４ａ、２４ｂメタライズ層
２中間リング
３、１４、１５接合部材
４固定側端板
５可動側端板
６固定通電軸
７固定電極
８可動電極
９可動通電軸
１０、２１、２８、３１、４０ベローズ
１１アークシールド
１２取付金具
１３絶縁円板
１６、２２固定側絶縁円板
１７可動側絶縁円板
１８第１の接合部材
１９第２の接合部材
２０第３の接合部材
２１ａ、２８ａ、３１ａ、４０ａベローズ自由端部
２２ｃ固定側絶縁円板の突出部
２３固定側絶縁円錐板
２４可動側絶縁円錐板
２５第４の接合部材
２６第５の接合部材
２７第６の接合部材
２９、３０、３４、３５シールドリング
３２第７の接合部材
３３第８の接合部材
３６固定側絶縁円筒
３７可動側絶縁円筒
３８第９の接合部材
３９第１０の接合部材
４１第１１の接合部材
４２、４３絶縁層[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a vacuum valve that suppresses electric field strength in a vacuum insulating container.
[0002]
[Prior art]
As is well known, a vacuum valve used in a vacuum circuit breaker utilizes the excellent arc extinguishing and insulating properties of a vacuum by contacting and separating a pair of electrodes in a high vacuum of about 10 ⁻² Pa or less. Current interruption is performed.
[0003]
A vacuum valve whose typical structure is shown in FIG. 11 is such that a cylindrical vacuum insulating container 1 made of, for example, ceramics is connected via an intermediate ring 2, and both ends of the vacuum insulating container 1 are made of metal and have an annular shape. They are sealed with a fixed side end plate 4 and a movable side end plate 5 via a joining member 3. A fixed energizing shaft 6 is fixed through the fixed end plate 4, and a fixed electrode 7 is fixed to an end surface portion of the fixed energizing shaft 6 in the vacuum insulating container 1.
[0004]
Opposite to the fixed electrode 7, a movable electrode 8 is fixed to an end surface portion in the vacuum insulating container 1 of a movable energizing shaft 9 connected to an operation mechanism (not shown). The central opening portion of the movable energizing shaft 9 and the movable side end plate 5 is kept airtight by the bellows 10 so that the movable energizing shaft 9 can be operated while maintaining a vacuum. Yes.
[0005]
In addition, the arc shield 11 is fixed to the intermediate ring 2 through the mounting bracket 12, and metal vapor and molten metal spattered from the electrodes 7 and 8 adhere to the inner surface of the insulating container 1, and creeping insulation performance Is prevented from falling.
[0006]
When a general vacuum valve as described above is used for a high voltage, it is necessary to improve the creeping insulation characteristics of the inner surface of the vacuum insulating container 1. Therefore, a method for increasing the creepage distance while maintaining the entire length of the vacuum insulating container 1 is known (for example, see Patent Document 1). This is because, as shown in FIG. 12, an annular insulating disk 13 made of, for example, ceramic is passed through the fixed energizing shaft 6, and the creeping distance of the insulating disk 13 is added to increase the creeping distance of the entire vacuum valve. It is something to be made.
[0007]
Further, the side surface on the inner diameter side of the insulating disk 13 and the fixed energizing shaft 6 are joined by a metal circular ring 14, and the side surface on the outer diameter side and the end surface of the vacuum insulating container 1 are connected. The space is joined by a metal arcuate joining member 15. These bondings are performed by forming metallized layers 1a, 13a, and 13b on the respective end faces of the vacuum insulating container 1 and the side surfaces of the insulating disc 13.
[0008]
The metallized layers 1a, 13a, and 13b are subjected to a metallization treatment in the vicinity of a brazed portion of the ceramic in advance when the ceramic and the metal are joined by silver brazing. For example, in the case of alumina ceramics, molybdenum and manganese fine powders are applied and heated at a high temperature to form a diffusion phase, and a metal layer such as nickel is formed thereon by plating.
[0009]
[Patent Document 1]
Japanese Patent Laid-Open No. 11-203996 (5th page, FIG. 9)
[0010]
[Problems to be solved by the invention]
According to the vacuum valve having the above-described configuration, the metallized layers 1a, 13a, and 13b of the metal layer are separated from the vacuum insulating container 1 made of an insulating material and the insulating disc 13 by vacuum insulation. It becomes a so-called triple junction in which the metal / insulator / insulating medium are combined, and the electric field strength is increased. In particular, in the insulating disc 13, the vacuum side portions of the metallized layers 13a and 13b are formed toward the electrode 7, and the creeping distance is shorter than that of the vacuum insulating container 1, so that the electric field strength is extremely increased. growing. In addition, since dielectric breakdown in vacuum shows electric field dependency, when a high voltage is applied to the vacuum bulb, discharge starts from the triple junction portion, causing dielectric breakdown on the inner surface of the vacuum bulb of the insulating disc 13. was there.
[0011]
Therefore, in order to use the vacuum valve for high voltage, the creeping distance of the vacuum insulating container 1 and the insulating disk 13 has to be increased. This goes against the recent trend of shrinking.
[0012]
An object of the present invention is to provide a vacuum valve that suppresses an increase in electric field strength due to a triple junction that is a starting point of dielectric breakdown.
[0016]
[Means for Solving the Problems]
The vacuum valve according to the present invention includes a pair of electrodes that are provided in a cylindrical vacuum insulating container and are detachable from each other, a fixed energizing shaft to which one of the electrodes is fixed, the fixed energizing shaft is penetrated, and An annular fixed-side insulating conical plate having a small-diameter portion provided in the opening on one side of the vacuum insulating container toward the electrode, and a small-diameter side and a large-diameter side on the outside air surface of the fixed-side insulating conical plate, respectively. A cross-section in which one end is joined through the small-diameter side and large-diameter side metallized layers, the small-diameter side of the fixed-side insulating conical plate and the metallized layer on the small-diameter side, and the other end is joined to the fixed-side conductive shaft One end is joined via the arcuate annular fourth joining member, the large-diameter side of the fixed-side insulating conical plate, and the metallized layer on the large-diameter side, and the other end is joined to one side of the vacuum insulating container An annular fifth joining member having an arcuate cross section, and the electrode And a movable energizing shaft to which one end of a bellows is secured, and an annular portion in which the movable energizing shaft is penetrated and a small-diameter portion is provided in the opening on the other side of the vacuum insulating container toward the electrode. A movable-side insulating conical plate, a small-diameter side and a large-diameter side metallization layer respectively applied to a small- diameter side and a large-diameter side on the outside air surface of the movable-side insulating conical plate, and a large-diameter side of the movable-side insulating conical plate And a sixth joining member having an arcuate cross section in which one end is joined via the metallization layer on the large diameter side and the other end is joined to the other side of the vacuum insulating container, and the movable side insulation the conical the bellows inside the conical plates provided, and is characterized in that via said small diameter side metallized layer between the small-diameter side of the movable side insulation conical plate bonding the free end portion of the bellows.
[0017]
As described above, according to the configuration of the present invention, the metallized layer of the insulating conical plate provided in the opening portions at both ends of the vacuum insulating container is provided on the outside air surface, the fourth joining member, the fifth joining member, In the triple junction where the three boundaries of metal / insulator / insulating medium are coupled to reduce the electric field of the portion located on the vacuum side in the metallized layer by the sixth joining member and the bellows free end. An increase in electric field strength can be suppressed.
[0018]
Therefore, since the electric field strength can be sufficiently suppressed on the vacuum side, the breakdown voltage characteristic showing the electric field dependency is improved, and the voltage of the vacuum valve can be increased.
[0019]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings. In addition, in each figure, the same code | symbol was attached | subjected about the component similar to the past.
[0020]
(First embodiment)
First, a vacuum valve according to a first embodiment of the present invention will be described with reference to FIG. FIG. 1 is a longitudinal sectional view of a vacuum valve according to the present embodiment.
[0021]
As shown in FIG. 1, the vacuum valve has a cylindrical vacuum insulating container 1 made of, for example, ceramic, connected via an intermediate ring 2, and has the same kind as the vacuum insulating container 1 at both ends of the vacuum insulating container 1. An annular fixed insulating disc 16 and an annular movable insulating disc 17 made of ceramic material are provided.
[0022]
On the fixed side of the vacuum valve, the fixed energizing shaft 6 is penetrated through the annular fixed-side insulating disc 16, and the first energizing member 18 having a circular cross-section made of metal is used to form the fixed energizing shaft 6. The periphery of the shaft and the inside surface of the fixed-side insulating disk 16 and the outside air-side surface are joined. Further, the outer side of the fixed-side insulating disc 16 and the outside-air-side surface and the end face of the vacuum insulating container 1 are joined by a second joining member 19 made of metal and having an arcuate cross section.
[0023]
On the other hand, on the movable side, an annular third joining member 20 made of metal and having an arc-shaped cross section is formed between the outer diameter side of the annular movable insulating disk 17 and between the outside air surface and the end face of the vacuum insulating container 1. Be joined. Moreover, the free end 21a of the bellows 21 whose one end is joined around the axis of the movable energizing shaft 9 is formed in an annular shape spreading outward in the radial direction, and the free end 21a of the movable-side insulating disc 17 is formed. It is joined to the outside surface on the inner diameter side.
[0024]
Metallized layers 1a, 16a, 16b, 17a, and 17b are formed on the vacuum insulating container 1, the annular fixed-side insulating disc 16, and the movable-side insulating disc 17, respectively, in a ring shape. Is done. The metallized layers 1a, 16a, 16b, 17a, 17b are silver brazed to the first joining member 18, the second joining member 19, the third joining member 20, and the free end 21a of the bellows 21. Are joined together.
[0025]
Further, the portions of the metallized layers 16a, 16b, 17a, and 17b of the fixed-side insulating disc 16 and the movable-side insulating disc 17 that are located on the vacuum side are the first joining member 18 and the second joining member. The free end portion 21a of the member 19, the third joining member 20, and the bellows 21 is positioned inside the curved portion having an arc shape.
[0026]
Note that a fixed electrode 7 and a movable electrode 8 are fixed oppositely in the vacuum insulating container 1 of the fixed energizing shaft 6 and the movable energizing shaft 9, respectively, and an operation (not shown) is performed on the movable energizing shaft 9. The mechanism is connected, and the electrodes 7 and 8 are contacted and separated. Further, an arc shield 11 is fixed to the intermediate ring 2 via a mounting bracket 12, and metal vapor and molten metal scattered from the electrodes 7, 8 adhere to the inner surface of the insulating container 1, and creeping insulation performance Is prevented.
[0027]
According to the first embodiment, the portions located on the vacuum side of the metallized layers 16a, 16b, 17a, and 17b in the annular fixed insulating disc 16 and the movable insulating disc 17 are respectively The first joining member 18, the second joining member 19, the third joining member 20, and the free end portion 21 a of the bellows 21 are positioned inside the arcuate curved portions. For this reason, the fixed-side insulating disk 16 and the movable-side insulating disk 17 made of an insulating material, and the vacuum insulating medium at the portion of the metal layer located on the vacuum side of the metallized layers 16a, 16b, 17a and 17b The increase in electric field strength at the triple junction that becomes the three boundaries is suppressed.
[0028]
Therefore, the breakdown voltage characteristic showing the electric field dependency is improved, and the voltage of the vacuum valve can be increased.
[0029]
In the first embodiment, the annular fixed-side insulating disc 16 is used. However, as shown in FIG. 2, the annular fixed-side insulating disc 22 having an annular protrusion 22c on the vacuum side. May be used. Even in this configuration, the portions located on the vacuum side in the annular metallized layers 22a and 22b are located inside the curvature portions of the first joining member 18 and the second joining member 19, so that the electric field strength at the triple junction is obtained. Rise is suppressed. Further, the creeping distance on the vacuum side can be increased.
[0030]
In the movable-side insulating disc, if a similar protrusion is provided on the vacuum side, an increase in electric field strength can be suppressed and the creeping distance on the vacuum side can be increased.
[0031]
(Second Embodiment)
Next, a vacuum valve according to a second embodiment of the present invention will be described with reference to FIG. FIG. 3 is a longitudinal sectional view of the vacuum valve according to the present embodiment. In the figure, the same components as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.
[0032]
As shown in FIG. 3, the vacuum valve is formed by connecting a cylindrical vacuum insulating container 1 made of, for example, ceramic via an intermediate ring 2, and the same kind of the vacuum insulating container 1 is provided at both ends of the vacuum insulating container 1. An annular fixed-side insulating conical plate 23 and an annular movable-side insulating conical plate 24 made of a material such as ceramic are provided. The small-diameter portions of the fixed insulating cone plate 23 and the movable insulating cone plate 24 are provided toward the fixed electrode 7 and the movable electrode 8, respectively.
[0033]
On the fixed side, the fixed energization shaft 6 penetrates the small diameter portion of the annular fixed side insulating conical plate 23, and the fixed energization is performed by the annular fourth joining member 25 made of metal and having a circular arc shape. The periphery of the shaft 6 is joined to the outside air side surface of the small diameter portion. Further, the outside air side surface of the large-diameter portion of the fixed-side insulating conical plate 23 and the end face of the vacuum insulating container 1 are joined by an annular fifth joining member 26 made of metal and formed in an arcuate cross section. .
[0034]
On the other hand, on the movable side, an annular sixth joining member 27 made of a metal and having an arcuate cross section is formed between the outside surface of the large-diameter portion of the movable-side insulating conical plate 24 and the end surface of the vacuum insulating container 1. Be joined. Further, a free end portion 28a of a bellows 28, which is provided inside the conical shape of the movable-side insulating conical plate 24 and has one end portion joined to the movable energizing shaft 9, is joined to the outside air surface of the small-diameter portion. The
[0035]
Metallized layers 1 a, 23 a, 23 b, 24 a, and 24 b are respectively formed on the portions that serve as joining surfaces of the vacuum insulating container 1, the fixed insulating cone plate 23, and the movable insulating cone plate 24. The free ends 28a of the fourth joining member 25, the fifth joining member 26, the sixth joining member 27, and the bellows 28 are silver brazed to the metallized layers 1a, 23a, 23b, 24a, 24b. Be joined.
[0036]
And the part located in the vacuum side in the metallized layers 23a, 23b, 24b of the fixed insulating cone plate 23 and the movable insulating cone plate 24 is the fourth bonding member 25, the fifth bonding member. The member 26 is located inside the curvature portion of the sixth joining member 27. Further, in the portion of the metallized layer 24a located on the vacuum side, the free end portion 28a of the bellows 28 is located close to the inner portion of the curvature portion.
[0037]
According to the second embodiment, the portions located on the vacuum side of the metallized layers 23a, 23b, and 24b are the fourth bonding member 25, the fifth bonding member 26, and the sixth bonding member 27, respectively. Since it is provided inside the curvature portion, an increase in electric field strength at the triple junction can be suppressed. Further, in the portion located on the vacuum side of the metallized layer 24a, the free end portion 28a of the bellows 28 is close to the inner portion of the curvature portion, so that an increase in electric field strength at the triple junction can be suppressed.
[0038]
Therefore, the breakdown voltage characteristic showing the electric field dependency is improved, and the voltage of the vacuum valve can be increased.
[0039]
Further, the creeping distance of the fixed-side insulating conical plate 23 and the movable-side insulating conical plate 24 is increased as compared with the fixed-side insulating disc 16 and the movable-side insulating disc 17 of the first embodiment.
[0040]
Furthermore, since the fixed insulating cone plate 23 is provided toward the fixed electrode 7 and the portion where the fixed energizing shaft 6 is thermally insulated in a vacuum can be shortened, heat dissipation characteristics are improved.
[0041]
As shown in FIG. 4, dish-shaped shield rings 29 and 30 are provided on the electrodes 7 and 8 side of the fixed-side insulating conical plate 23 and the movable-side insulating conical plate 24 used in the second embodiment. The fixed energizing shaft 6 and the movable energizing shaft 9 may be fixed.
[0042]
Thereby, since the site | part located in the vacuum side of the said metallization layers 23a and 24a is each covered with the said shield rings 29 and 30, the raise of the electric field strength by a triple junction can be suppressed.
[0043]
Further, the shield rings 29 and 30 can prevent the metal vapor generated when the current is interrupted between the electrodes 7 and 8 from adhering to the surfaces of the insulating conical plates 23 and 24.
[0044]
Furthermore, in the second embodiment, on the movable side, the bellows 28 is provided on the conical inner side of the movable insulating conical plate 24. However, as shown in FIG. A bellows 31 may be provided between the movable electrodes 8. Also in this case, the free end portion 31 a of the bellows 31 is joined to the metallized layer 24 a provided on the outside air surface of the small diameter portion of the movable insulating conical plate 24.
[0045]
Thereby, in addition to the effect of the second embodiment, the portion where the movable energizing shaft 9 is thermally insulated in a vacuum is shortened, so that the heat dissipation characteristics are improved. Further, since the bellows 31 is provided inside the vacuum insulating container 1, damage due to external force can be prevented.
[0046]
(Other embodiments)
A vacuum valve according to another embodiment of the present invention will be described with reference to FIGS. 6 is a longitudinal sectional view of the fixed side of the vacuum valve according to the present embodiment, FIG. 7 is a longitudinal sectional view of the fixed side of the vacuum valve according to the present embodiment, and FIG. 8 is according to the present embodiment. FIG. 9 is a vertical cross-sectional view of the vacuum valve according to the present embodiment, FIG. 9 is a vertical cross-sectional view of the vacuum valve according to the present embodiment, and FIG. 10 is a vertical cross-sectional view of the vacuum valve according to the present embodiment. 6 to 10, the same components as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.
[0047]
First, a configuration for reducing electric field in another embodiment of the present invention will be described. As shown in FIG. 6, on the fixed side of the vacuum valve, an annular metallized layer 16 c is formed on the vacuum side surface on the inner diameter side of the annular fixed insulating disc 16 penetrating the fixed energizing shaft 6. Then, one end of an annular seventh joining member 32 made of metal having a larger outer diameter than the outer diameter of the metallized layer 16c and having a C-shaped cross section is joined by, for example, silver brazing via the metallized layer 16c, The other end is joined around the fixed energizing shaft 6.
[0048]
Metallized layers 16d and 1a are provided on the outer diameter side surface of the fixed-side insulating disc 16 and the end surface of the vacuum insulating container 1, respectively, and an annular eighth joint member made of metal and having an arc-shaped cross section is provided therebetween. 33 is joined by, for example, silver brazing. In the vicinity of the metallized layer 16d side of the fixed insulating disc 16 of the eighth bonding member 33, an annular shield ring 34 whose tip is curved toward the fixed energizing shaft 6 is fixed. .
[0049]
As described above, the portion where the metallized layer 16c on the inner diameter side of the fixed insulating disc 16 is positioned on the vacuum side is close to the curved surface of the outer periphery on which the seventh bonding member 32 is curved. Further, the portion of the metallized layer 16d on the outer diameter side that is located on the vacuum side is covered inside the curved curvature portion of the shield ring 34.
[0050]
According to the above embodiment, since the portion located on the vacuum side of the metallized layer 16c is close to the seventh bonding member 32, an increase in electric field strength at the triple junction can be suppressed. Moreover, since the site | part located in the vacuum side of the said metallization layer 16d is covered inside the curvature part of the said shield ring 34, the raise of the electric field strength in a triple junction is suppressed.
[0051]
In the fixed energizing shaft 6 used in the above embodiment, the fixed energizing shaft 6 protrudes around the outside air-side shaft that penetrates the fixed-side insulating disc 16 as shown in FIG. A shield ring 35 may be provided. The shield ring 35 is attached to the fixed energizing shaft 6 after the vacuum valve is assembled. As a result, the entire metallized layer 16c is sandwiched between the vacuum-side seventh joining member 32 and the outside-air-side shield ring 35, and an increase in electric field strength at the triple junction is suppressed.
[0052]
In the other embodiments described above, the fixed side has been described. However, by providing the shield ring 34 similar to the above on the movable side as well, an increase in electric field strength due to triple junction can be suppressed.
[0053]
Next, a configuration for increasing the creepage distance according to still another embodiment of the present invention will be described. As shown in FIG. 8, the vacuum valve has a cylindrical vacuum insulating container 1 made of, for example, ceramic, connected via an intermediate ring 2, and fixed side insulation made of, for example, ceramic in the opening at both ends of the vacuum insulating container 1. A cylinder 36 and a movable insulating cylinder 37 are provided coaxially with the vacuum insulating container 1.
[0054]
One end of an annular ninth joining member 38 made of metal and having a U-shaped cross section is joined to one side of the vacuum insulating container 1, and the other end is joined to one side of the fixed-side insulating cylinder 36. Is done. In addition, one end of an annular tenth joining member 39 made of metal and having a U-shaped cross section is joined to the other side of the fixed-side insulating cylinder 36, and the other end is joined to the periphery of the fixed energizing shaft 6. Is done.
[0055]
On the other hand, on the movable side, one end of an annular eleventh joining member 41 made of metal and having a U-shaped cross section is joined to the other side of the vacuum insulating container 1, and the other end of the movable insulating cylinder 37. Bonded to one side. Furthermore, the free end 40a of the bellows 40 having one end joined to the movable energizing shaft 9 spreads outward in the radial direction and joined to the other end of the movable insulating cylinder 37, and the vacuum insulating container The inside of 1 is kept at a high vacuum.
[0056]
According to the above embodiment, the creeping distance of the vacuum valve is increased by the fixed insulating cylinder 36 and the movable insulating cylinder 37.
[0057]
As shown in FIG. 9, if an insulating layer 42 is provided in a portion where the fixed energizing shaft 6 penetrates the ninth joining member 38, the space between the fixed energizing shaft 6 and the ninth joining member 38 is provided. Dielectric strength can be improved.
[0058]
Further, as shown in FIG. 10, if an insulating layer 43 is provided on the surface of the ninth joining member 38 in addition to the insulating layer 42 provided on the fixed energizing shaft 6, the fixed energizing shaft 6 and the ninth The dielectric strength between the joining members 38 is further improved. Similarly, if the insulating layer is provided on the eleventh bonding member 41 on the movable side, the dielectric strength with respect to the bellows 40 can be improved.
[0059]
The present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the invention. For example, in the first and second embodiments, all of the vacuum insulating container 1, the fixed-side insulating disks 16 and 22, the movable-side insulating disk 17, the fixed-side insulating cone plate 23, and the movable-side insulating cone plate 24 are all attached. The same kind of material. These are made of different materials having different dielectric constants, and from the vacuum insulating container 1, the fixed-side insulating disc 16, the movable-side insulating disc 17, the fixed-side insulating conical plate 23, and the movable-side insulating conical plate 24. The relative dielectric constant may be reduced.
[0060]
As a result, when the vacuum valve is incorporated in the vacuum circuit breaker, the potential sharing due to capacitive coupling with the ground such as the mounting plate of the vacuum circuit breaker can be improved. That is, the potentials of the second joining member 19, the third joining member 20, the fifth joining member 26, the sixth joining member 27, and the eighth joining member 33 are the specific capacitance on the ground side. Is greatly displaced toward the ground potential, but the degree of this displacement can be suppressed.
[0061]
【The invention's effect】
As described above, according to the present invention, the metallization layer is applied to the outside air side surface of the insulating plate provided at the both end openings of the vacuum insulation container, and the joining member is joined via the metallization layer, whereby the vacuum side Since the increase in electric field strength at the triple junction where the three boundaries of the metal layer, the insulating insulating plate, and the vacuum insulating medium are combined can be suppressed, electric field dependency is exhibited. The breakdown voltage characteristics are improved, and the voltage of the vacuum valve can be increased.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view showing a vacuum valve according to a first embodiment of the present invention.
FIG. 2 is a longitudinal sectional view of an essential part on a fixed side showing a vacuum valve according to a modification of the first embodiment of the present invention.
FIG. 3 is a longitudinal sectional view showing a vacuum valve according to a second embodiment of the present invention.
FIG. 4 is a longitudinal sectional view showing a vacuum valve according to a modification of the second embodiment of the present invention.
FIG. 5 is a longitudinal sectional view showing a vacuum valve according to a modification of the second embodiment of the present invention.
FIG. 6 is a longitudinal sectional view of an essential part on the fixed side showing a vacuum valve according to another embodiment of the present invention.
FIG. 7 is a longitudinal sectional view of an essential part on the fixed side showing a vacuum valve according to another embodiment of the present invention.
FIG. 8 is a longitudinal sectional view showing a vacuum valve according to another embodiment of the present invention.
FIG. 9 is a longitudinal sectional view of an essential part on the fixed side showing a vacuum valve according to another embodiment of the present invention.
FIG. 10 is a longitudinal sectional view of an essential part on the fixed side showing a vacuum valve according to another embodiment of the present invention.
FIG. 11 is a longitudinal sectional view showing a conventional vacuum valve.
FIG. 12 is a longitudinal sectional view of a main part on the fixed side showing a conventional vacuum valve.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Vacuum insulation container 1a, 13a, 13b, 16a, 16b, 16c, 16d, 17a, 17b, 22a, 22b, 23a, 23b, 24a, 24b Metallization layer 2 Intermediate ring 3, 14, 15 Joining member 4 Fixed side end plate 5 Movable side end plate 6 Fixed energizing shaft 7 Fixed electrode 8 Movable electrode 9 Movable energizing shaft 10, 21, 28, 31, 40 Bellows 11 Arc shield 12 Mounting bracket 13 Insulating disk 16, 22 Fixed side insulating disk 17 Movable side Insulating disk 18 1st joining member 19 2nd joining member 20 3rd joining members 21a, 28a, 31a, 40a Bellows free end 22c Fixed side insulating disc protrusion 23 Fixed side insulating conical plate 24 Movable side Insulating conical plate 25 4th joining member 26 5th joining member 27 6th joining members 29, 30, 34, 35 Shield ring 32 7th joining member 33 1st Joining member 41 11th joint member 36 fixed side insulation cylinder 37 movable insulating cylinder 38 ninth joint member 39 tenth of joint members 42, 43 insulating layer

Claims

A pair of electrodes which are provided in a cylindrical vacuum insulating container and can be separated from each other;
A fixed energizing shaft to which one of the electrodes is fixed;
An annular fixed-side insulating conical plate in which the fixed energizing shaft is penetrated and a small-diameter portion is provided toward the electrode at an opening on one side of the vacuum insulating container;
A metallized layer on the small diameter side and the large diameter side respectively applied to the small diameter side and the large diameter side on the outside air surface of the fixed-side insulating conical plate;
A fourth joint member having an arcuate cross section in which one end is joined via the metallization layer on the small diameter side and the small diameter side of the fixed-side insulating conical plate, and the other end is joined to the fixed-side conductive shaft;
A fifth joint having an annular cross-section in which one end is joined via the large-diameter side of the fixed-side insulating conical plate and the metallized layer on the large-diameter side, and the other end is joined to one side of the vacuum insulating container. A member,
A movable energizing shaft to which the other of the electrodes is fixed and one end of a bellows is fixed;
An annular movable-side insulating conical plate that is penetrated by the movable energizing shaft and has a small-diameter portion provided at the opening on the other side of the vacuum insulating container toward the electrode;
A small-diameter side and a large-diameter side metallization layer each applied to a small-diameter side and a large-diameter side on the outside-air-side surface of the movable insulating conical plate;
A sixth joint having an arcuate cross section in which one end is joined via the metallized layer on the large diameter side and the large diameter side of the movable insulating conical plate, and the other end is joined to the other side of the vacuum insulating container. And having a member
Wherein the conical the bellows inside the movable side insulation conical plate provided was joined to the free end of the bellows and through the small-diameter side diameter side metallized layer of said movable insulating conical plate A vacuum valve.

2. A shield ring is provided on each of the fixed energizing shaft between the fixed-side insulating conical plate and the electrode and on the movable energizing shaft between the movable-side insulating conical plate and the electrode. The vacuum valve as described in .

The vacuum valve according to claim 1, wherein the bellows is provided between a small diameter portion of the movable insulating conical plate and the electrode .