JP3713787B2

JP3713787B2 - Vacuum capacitor

Info

Publication number: JP3713787B2
Application number: JP02291496A
Authority: JP
Inventors: 祥弘深津; 利眞深井
Original assignee: Meidensha Corp
Current assignee: Meidensha Corp
Priority date: 1996-02-09
Filing date: 1996-02-09
Publication date: 2005-11-09
Anticipated expiration: 2016-02-09
Also published as: JPH09219342A

Description

【０００１】
【発明の属する技術分野】
本発明は大電力送信機の発振回路とか半導体製造装置用の高周波電源、あるいは誘導加熱装置のタンク回路等に用いられる真空コンデンサに関する。
【０００２】
【従来の技術】
上記真空コンデンサの一例として、本出願人は先に特願平６−２３３９１２号により図４に示す可変形真空コンデンサを提案した。この真空コンデンサの基本構成を説明すると、セラミック等の絶縁円筒１２の両端側に銅製の円筒管１１ａ，１１ｂを接合して円筒部を形成し、この円筒部を固定側端板兼固定電極取付導体１３（以下、固定電極取付導体と略称）と可動側端板１４により閉塞してコンデンサ部を収容する真空容器１０を形成する。
【０００３】
この固定電極取付導体１３の内側には、径（半径）の異なる複数の円筒状電極板Ｆ₁，Ｆ₂・・・・Ｆ_nを同心円状に一定間隔をもって取り付けて固定電極１５を形成しており、この固定電極１５の各電極板間の間隙内に、非接触状態で挿出入できるように内径の異なる複数の円筒状電極板Ｍ₁，Ｍ₂・・・・Ｍ_nを可動電極取付導体１８に設けて可動電極１６を形成している。
【０００４】
上記固定電極１５と可動電極１６とを電気的に絶縁するために、真空容器１０の円筒部はセラミック等による絶縁円筒で形成されている。又、固定側電極取付導体１３の内側で円筒状電極板Ｆ₁〜Ｆ_nの同心部に、円筒状電極板の軸線に沿ってガイドピン１を設けるとともに、可動電極取付導体１８側にこのガイドピン１を挿入するガイドピン挿入孔を有するガイド部５を可動リード２と一体に設けて案内部を形成し、このガイド部５内にガイドピン１を摺動自在に挿入して可動電極１６をガイドピン１で案内して移動可能とし、固定側の円筒状電極板と一定間隔を保ちながら可動側の円筒状電極板を移動させて可動リード２の傾きに起因する耐電圧、静電容量の不安定さをなくしている。
【０００５】
上記ガイド部５は可動リード２と一体に形成するか、可動電極取付導体１８と一体又は別個に設けてもよい。又、ガイドピン１を可動電極取付導体１８側に設け、ガイド部５を固定側端板１３側に設けてもよい。
【０００６】
上記固定電極１５と可動電極１６とは電気的に絶縁する必要があるため、ガイドピン１とガイド部５とは電気的に絶縁されなければならないが、この絶縁手段としてはガイドピン１およびガイド部５のいずれか一方を絶縁材料で構成すればよい。又、摺動性の円滑を保つためにガイドピン１をセラミック、特にアルミナによるセラミックで形成し、ガイド部５をリン青銅で形成すると好適であり、更にガイドピン１を金属性にし、その表面に滑性の優れたナイロン樹脂をコーティングする手段も有効である。
【０００７】
３１はねじ受部であり、該ねじ受部３１は可動側端板１４の内側に立設され、内端部に鍔部３１ａが設けてある。３２は外周にねじが螺設された可動リードボルトであって、一端側は可動リード２を短くしたその先端部の接続部３７に取付けられ、他端側は軸線に沿って前記鍔部３１ａ内の空隙を遊貫してねじ受部３１内に突き出されている。３３は調整ナットであり、その一端側はねじ受部３１内に突出した可動リードボルト３２の端部に螺合し、ベアリング等の軸受３４を介して鍔部３１ａの内底に回転自在に取付けられている。
【０００８】
１９はベローズであり、一端が可動側端板１４にロー付けされ、他端側は可動リード２又は可動導体１８にロー付けされている。このベローズ１９は可動リード２の摺動部と可動側端板１４の貫通部を覆っており、真空漏れを防止しながら可動リード２の上下動ができるようにしている。
【０００９】
３５は最大静電容量調節部であって、該最大静電容量調節部３５は調整ナット３３の内側にあって前記可動リードボルト３２の先端に設けたねじ穴に螺入する調節ねじ３６と、調節ねじ３６が挿入されるように調整ナット３３の内側に形成された大径部３３ａ及び段部３３ｂとから形成されている。
【００１０】
４０は駆動モータであり、上記調整ナット３３と駆動モータ４０の出力シャフト４０ａに固定されたスプロケット４１との間に回転力を伝達するベルト４２が取付けられている。
【００１１】
このような真空コンデンサによれば、最大静電容量値を調節する場合には先ず調節ねじ３６を可動リードボルト３２の先端に螺入して固定する前に調整ナット３３を若干右に回し（右ねじの場合）、ガイドピン１の先端１ａと可動リードボルト３２の接続部３７の終端面とが突き当たる最大静電容量の位置より若干可動リード２を下方に移動させ、定義した最大静電容量値に調節する。この若干の調節量は真空コンデンサの静電容量のばらつきの程度で決まる。
【００１２】
この状態で調節ねじ３６をその頭部の当接面が段部３３ｂに当接するまで螺入し、当接したところで調節ねじ３６を可動リードボルト３２に接着剤等で固定し、可動リードボルト３２の上昇位置を規制する（調整ナット３３とは接着しない）。このように可動リードボルト３２の上昇位置を規制することにより、製作された真空コンデンサの最大静電容量値にばらつきがあっても、各真空コンデンサごとに最大静電容量値が調節でき、定義された最大静電容量値に合致した品質の真空コンデンサが得られる。
【００１３】
真空コンデンサの静電容量値の調整は、駆動モータ４０の作用によって調整ナット３３を左右に回転することにより、例えば右回転では可動リードボルト３２が下方に移動し、左回転では上方に移動して可動電極１６が上下動を行い、固定電極１５との対向総面積を可変して静電容量を任意に調整することができる。この最大静電容量値の位置よりも調整ナット３３を左に回そうとしても調節ねじ３６が段部３３ｂに当たってそれ以上左に回らないので、調節ねじ３６は調整ナット３３が可動リードボルトから抜けるのを防止するストッパの機能をも合わせ持っている。
【００１４】
【発明が解決しようとする課題】
前記したように真空コンデンサの静電容量値を調整する場合には、駆動モータ４０の回転力を出力シャフト４０ａに固定されたスプロケット４１とベルト４２を介して調整ナット３３に伝達することにより、可動電極１６が上下動を行って固定電極１５との対向総面積が可変され、任意に調整することができるが、このような操作時に調整ナット３３には図示上で横方向、即ち、該調整ナット３３の回転軸に対して垂直な方向の力が加えられることになるため、この外力によって調整ナット３３が横方向に動く「ぶれ」現象が生じるという難点がある。
【００１５】
即ち、調整ナット３３と可動リードボルト３２とのねじ部には多少のガタがあるため、調整ナット３３が横方向に動くと該調整ナット３３の回転軸と可動リードボルト３２の軸がずれることがあり、このような状態で調整ナット３３を更に回転させると、ねじ部の摩擦が増加して調整ナット３３の回転に要するトルクが上昇したり、ねじ部の「かじり」等が発生して部品の寿命が低下してしまうことになりやすい。
【００１６】
又、このような横方向力が比較的大きな場合には、調整ナット３３を動かすだけでなく該調整ナット３３から可動リードボルト３２を経て可動リード２にも横方向力が加わるが、するとガイド部５とガイドピン１間の摩擦が増加し、これによっても調整ナット３３の回転に要するトルクが上昇することがある。更にガイド部５とガイドピン１には多少の公差があるため、ガイド部５は力を受けた方向に公差の距離だけ移動するが、それに伴って可動側の円筒状電極板Ｍ₁，Ｍ₂，・・・・Ｍｎも同じ方向に移動して固定側の円筒状電極板Ｆ₁，Ｆ₂・・・・Ｆ_nとの距離が短くなり、耐電圧が低下するという問題も生じる。
【００１７】
本発明は以上の点に鑑みてなされたものであって、真空コンデンサの静電容量値を調整する際に調整ナットを回転しても該調整ナットに横方向の力が加えられることがなく、これにより調整ナットの回転軸と可動リードボルトの軸の「ずれ」を防止するとともに、ねじ部の摩擦増加に起因する調整ナットの回転トルクの上昇を防止し、合わせてねじ部の「かじり」による部品の寿命低下がない真空コンデンサを提供することを目的とするものである。
【００１８】
本発明は上記の目的を達成するために、円筒部の一端側に固定側端板を有し、他端側に可動側端板を有する真空容器と、該真空容器内にあって同心円状で径の異なる複数の円筒状電極板を固定電極取付導体に取り付けて形成した固定電極と、この固定電極の各円筒状電極板間に非接触状態で挿出入できるように径の異なる複数の円筒状電極板を可動電極取付導体に取り付けて形成した可動電極と、該可動電極を前記真空容器の可動側端板の外部から円筒状電極板の軸線方向に移動させる可動リードと、該可動リードの外周側で前記可動側端板の内側に設けられ、真空状態を保持した状態で可動リードの移動を可能とするベローズと、前記固定電極取付導体と可動電極取付導体の相対向する面の中心部に夫々設けられたガイドピン及びこのガイドピンを電気的に絶縁して摺動自在に挿入するガイド部と、前記可動リードの先端部に軸線方向に取付けられた可動リードボルトと、前記可動側端板の内側でベローズ内に突出したねじ受部、及び該ねじ受部と軸受を介して支持され、前記可動リードボルトに螺合する調整ナットとを備え、該調整ナットの回転操作によりコンデンサの静電容量を調整するようにした真空コンデンサにおいて、
前記調整ナットと前記ねじ受部との間に、ニードルベアリングを配設したことを特徴とするものである。
【００１９】
更に請求項２により、円筒部の一端側に固定側端板を有し、他端側に可動側端板を有する真空容器と、該真空容器内にあって同心円状で径の異なる複数の円筒状電極板を固定電極取付導体に取り付けて形成した固定電極と、この固定電極の各円筒状電極板間に非接触状態で挿出入できるように径の異なる複数の円筒状電極板を可動電極取付導体に取り付けて形成した可動電極と、該可動電極を前記真空容器の可動側端板の外部から円筒状電極板の軸線方向に移動させる可動リードと、該可動リードの外周側で前記可動側端板の内側に設けられ、真空状態を保持した状態で可動リードの移動を可能とするベローズと、前記固定電極取付導体と可動電極取付導体の相対向する面の中心部に夫々設けられたガイドピン及びこのガイドピンを電気的に絶縁して摺動自在に挿入するガイド部と、前記可動リードの先端部に軸線方向に取付けられた可動リードボルトと、前記可動側端板の内側でベローズ内に突出したねじ受部、及び該ねじ受部と軸受を介して支持され、前記可動リードボルトに螺合する調整ナットとを備え、該調整ナットの回転操作によりコンデンサの静電容量を調整するようにした真空コンデンサにおいて、
前記可動側端板の下面に、内周側フランジ部を有するニードルベアリング取付ブラケットを固着し、このニードルベアリング取付ブラケットの内周側フランジ部と前記調整ナットとの間にニードルベアリングを配設したことを特徴とするものである。
また、請求項３は、円筒部の一端側に固定側端板を有し、他端側に可動側端板を有する真空容器と、該真空容器内にあって同心円状で径の異なる複数の円筒状電極板を固定電極取付導体に取り付けて形成した固定電極と、この固定電極の各円筒状電極板間に非接触状態で挿出入できるように径の異なる複数の円筒状電極板を可動電極取付導体に取り付けて形成した可動電極と、該可動電極を前記真空容器の可動側端板の外部から円筒状電極板の軸線方向に移動させる可動リードと、該可動リードの外周側で前記可動側端板の内側に設けられ、真空状態を保持した状態で可動リードの移動を可能とするベローズと、前記固定電極取付導体と可動電極取付導体の相対向する面の中心部に夫々設けられたガイドピン及びこのガイドピンを電気的に絶縁して摺動自在に挿入するガイド部と、前記可動リードの先端部に軸線方向に取付けられた可動リードボルトと、前記可動側端板の内側でベローズ内に突出したねじ受部、及び該ねじ受部と軸受を介して支持され、前記可動リードボルトに螺合する調整ナットとを備え、該調整ナットの回転操作によりコンデンサの静電容量を調整するようにした真空コンデンサにおいて、
前記可動側端板の下面に、内周側フランジ部を有する外部導体を固着し、この外部導体の内周側フランジ部と前記調整ナットとの間にニードルベアリングを配設したことを特徴とするものである。
【００２０】
かかる真空コンデンサによれば、調整ナットとねじ受け部との間に嵌合した状態に配備したニードルベアリングが調整ナットに加えられる横方向の力を受け止め、外力に起因する調整ナットの「ぶれ」現象を防止し、且つ調整ナットの回転軸と可動リードボルトの軸は一致したまま保持されるので、ねじ部の摩擦増加に伴う調整ナットの回転トルクの上昇はなく、ねじ部の「かじり」に伴う部品の寿命低下とか、ガイド部とガイドピン間に存在する公差に起因する耐電圧の低下現象は防止される。
【００２１】
請求項２記載の構成によれば、可動側端板の下面にニードルベアリング取付ブラケットを固着したことにより、設計上の自由度が広げられ、請求項３記載の構成によれば可動側端板の下面に直接外部導体を固着したことにより、構成が簡易化される作用が得られる。
【００２２】
【発明の実施の形態】
以下本発明の各種実施例を図面に基づいて説明する。図１は本発明の第１実施例を示す構成図であって、図示例では縦断正面図として示している。尚、前記図４と同一構成部分には同一の符号を付して表示してある。
【００２３】
１２はセラミック等の絶縁円筒であり、この絶縁円筒１２の両端側に銅製の円筒管１１ａ，１１ｂを接合して円筒部を形成し、この円筒部を固定電極取付導体１３と可動側端板１４により閉塞してコンデンサ部を収容する真空容器１０を形成する。固定電極取付導体１３の内側には、径（半径）の異なる同心円状の複数の円筒状電極板Ｆ₁，Ｆ₂・・・・Ｆ_nを一定間隔をもって取り付けてあり、固定電極１５を形成する。この固定電極１５の各電極板間の間隙内に、非接触状態で挿出入できるように内径の異なる複数の円筒状電極板Ｍ₁，Ｍ₂・・・・Ｍ_nを可動電極取付導体１８に設けて可動電極１６を形成している。
【００２４】
上記固定側電極取付導体１３の内側で円筒状電極板Ｆ₁〜Ｆ_nの同心部に、円筒状電極板の軸線に沿ってガイドピン１を設け、可動電極取付導体１８側にこのガイドピン１を挿入するガイドピン挿入孔を有するガイド部５を可動リード２と一体に設けて案内部を形成し、このガイド部５内にガイドピン１を摺動自在に挿入して可動電極１６をガイドピン１で案内して移動可能とし、固定側の円筒状電極板と一定間隔を保ちながら可動側の円筒状電極板を移動させて可動リード２の傾きに起因する耐電圧、静電容量の不安定さをなくしている。上記ガイドピン１を可動電極取付導体１８側に設け、且つガイド部５を固定側端板１３側に設けてもよい。
【００２５】
３１はねじ受部であり、該ねじ受部３１は可動側端板１４の内側に立設され、内端部に鍔部３１ａが設けてある。３２は外周にねじが螺設された可動リードボルトであって、一端側は可動リード２を短くしたその先端部の接続部３７に取付けられ、他端側は軸線に沿って前記鍔部３１ａ内の空隙を遊貫してねじ受部３１内に突き出されている。３３は調整ナットであり、その一端側はねじ受部３１内に突出した可動リードボルト３２の端部に螺合し、ベアリング等の軸受３４を介して鍔部３１ａの内底に回転自在に取付けられている。
【００２６】
１９はベローズであり、一端が可動側端板１４にロー付けされ、他端側は可動リード２又は可動導体１８にロー付けされている。このベローズ１９は可動リード２の摺動部と可動側端板１４の貫通部を覆っており、真空漏れを防止しながら可動リード２の上下動ができるようにしている。
【００２７】
調整ナット３３の内側には、前記可動リードボルト３２の先端に設けたねじ穴に螺入する調節ねじ３６と、調節ねじ３６が挿入されるように調整ナット３３の内側に形成された大径部３３ａ及び段部３３ｂが形成されている。
【００２８】
そして本実施例では、上記調整ナット３３とねじ受け部３１との間にニードルベアリング４５を嵌合した状態に配備してある。
【００２９】
４０は駆動モータであり、この駆動モータ４０の出力シャフト４０ａに固定されたスプロケット４１と前記調整ナット３３との間に回転力を伝達するベルト４２が取付けられている。
【００３０】
このような真空コンデンサによれば、最大静電容量値を調節する場合には調節ねじ３６を可動リードボルト３２の先端に螺入して固定する前に調整ナット３３を若干右に回し（右ねじの場合）、ガイドピン１の先端１ａと可動リードボルト３２の接続部３７の終端面とが突き当たる最大静電容量の位置より若干可動リード２を下方に移動させ、定義した最大静電容量値に調節する。この若干の調節量は真空コンデンサの静電容量のばらつきの程度で決まる。
【００３１】
この状態で調節ねじ３６をその頭部の当接面が段部３３ｂに当接するまで螺入し、当接したところで調節ねじ３６を可動リードボルト３２に接着剤等で固定し、可動リードボルト３２の上昇位置を規制する。
【００３２】
真空コンデンサの静電容量値の調整は、駆動モータ４０の回転力を出力シャフト４０ａからベルト４２を介して調整ナット３３に伝達し、この調整ナット３３を左右に回転することによって可動リードボルト３２が上下に移動して可動電極１６が上下動を行い、固定電極１５との対向総面積が変化して静電容量を任意に調整することができる。
【００３３】
この時に調整ナット３３とねじ受け部３１との間に嵌合した状態に配備したニードルベアリング４５が調整ナット３３に加えられる横方向の力を受け止めて、外力に起因する調整ナット３３の「ぶれ」現象を防止し、調整ナット３３の回転軸と可動リードボルト３２の軸を一致したままの状態に保持することができる。従ってねじ部の摩擦増加に伴う調整ナット３３の回転トルクの上昇はなく、ねじ部の「かじり」に伴う部品の寿命低下とか、ガイド部５とガイドピン１間に存在する公差に起因する耐電圧の低下現象を防止することができる。
【００３４】
図２は本発明の第２実施例を示す要部拡大図であり、この例では可動側端板１４の下面にニードルベアリング取付ブラケット４６を固着して、このニードルベアリング取付ブラケット４６の内周側フランジ部４６ａと調整ナット３３との間にニードルベアリング４５を嵌合した状態に配備してある。４７はニードルベアリング取付ブラケット４６に固着された外部導体である。この外部導体４７は図示したようにニードルベアリング取付ブラケット４６に直接固着するか、もしくは可動側端板１４とニードルベアリング取付ブラケット４６との間に嵌挿して固着してもよい。
【００３５】
かかる第２実施例の基本的作用は第１実施例と同一であるが、第１実施例に比較して可動側端板１４の下面にニードルベアリング取付ブラケット４６を固着したことにより、設計上の自由度が広がるという利点がある。
【００３６】
図３は本発明の第３実施例を示す要部拡大図であり、この例では可動側端板１４の下面に直接外部導体４７を固着して、この外部導体４７の内周側フランジ部４７ａと調整ナット３３との間にニードルベアリング４５を嵌合した状態に配備してある。
【００３７】
かかる第３実施例の基本的作用は第１実施例と同一であるが、可動側端板１４の下面に直接外部導体４７を固着したことにより、構成が簡易化される利点がある。
【００３８】
【発明の効果】
以上詳細に説明したように、本発明にかかる真空コンデンサは、静電容量値の調整時に駆動モータ等の回転力を利用して調整ナットを回転する際に、調整ナットとねじ受け部との間に嵌合した状態に配備したニードルベアリングが調整ナットに加えられる横方向の力を受け止めて「ぶれ」現象が防止されるので、調整ナットの回転軸と可動リードボルトの軸は一致したまま保持されてねじ部の摩擦増加に伴う調整ナットの回転トルクの上昇現象はなくなり、且つねじ部の「かじり」に伴う部品の寿命低下とか、ガイド部とガイドピン間に存在する公差に起因する耐電圧の低下現象を防止することができる。
【００３９】
特に上記横方向力が比較的大きな場合には、調整ナットから可動リードボルトを経て可動リードにも横方向力が加わり、ガイド部とガイドピン間の摩擦が増加して調整ナットの回転に要するトルクが上昇したり耐電圧が低下するという懸念があるが、本発明によれば上記の難点を確実に解消する効果が得られる。
【００４０】
更に請求項２記載の構成によれば、可動側端板の下面にニードルベアリング取付ブラケットを固着したことによって設計上の自由度が広げられ、請求項３記載の構成によれば可動側端板の下面に直接外部導体を固着したことにより、構成が簡易化されるという効果が得られる。
【００４１】
又、製作された真空コンデンサの最大静電容量値は簡単に調節可能であって、定義する最大静電容量値に合致することが可能であり、最大静電容量値のばらつきを無くして均一な最大静電容量値の真空コンデンサを得ることができる。
【図面の簡単な説明】
【図１】本発明の第１実施例を示す構成図。
【図２】本発明の第２実施例の要部拡大図。
【図３】本発明の第３実施例の要部拡大図。
【図４】本発明が適用した真空コンデンサの基本構成図。
【符号の説明】
１…ガイドピン
２…可動リード
５…ガイド部
１０…真空容器
１３…固定電極取付導体
１１ａ，１１ｂ…円筒管
１２…絶縁内筒
１４…可動側端板
１５…固定電極
１６…可動電極
１８…可動電極取付導体
１９…ベローズ
３１…ねじ受部
３２…可動リードボルト
３３…調整ナット
３４…軸受
３６…調節ねじ
３７…接続部
４０…駆動モータ
４５…ニードルベアリング
４６…ニードルベアリング取付ブラケット
４７…外部導体
４６ａ，４７ａ…フランジ部[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a vacuum capacitor used in an oscillation circuit of a high-power transmitter, a high-frequency power source for a semiconductor manufacturing apparatus, a tank circuit of an induction heating apparatus, or the like.
[0002]
[Prior art]
As an example of the vacuum capacitor, the present applicant previously proposed a variable vacuum capacitor shown in FIG. 4 according to Japanese Patent Application No. 6-233912. The basic configuration of this vacuum capacitor will be described. A cylindrical portion is formed by joining copper cylindrical tubes 11a and 11b to both ends of an insulating cylinder 12 made of ceramic or the like, and this cylindrical portion is used as a fixed side end plate / fixed electrode mounting conductor. 13 (hereinafter abbreviated as “fixed electrode mounting conductor”) and the movable side end plate 14 are closed to form the vacuum vessel 10 that houses the capacitor portion.
[0003]
Inside the fixed electrode mounting conductor 13, a plurality of cylindrical electrode plates F ₁ , F ₂ ... F _n having different diameters (radius) are mounted concentrically at regular intervals to form a fixed electrode 15. A plurality of cylindrical electrode plates M ₁ , M ₂ ... M _n having different inner diameters are inserted into the gaps between the electrode plates of the fixed electrode 15 in a non-contact state. The movable electrode 16 is formed at 18.
[0004]
In order to electrically insulate the fixed electrode 15 and the movable electrode 16, the cylindrical portion of the vacuum vessel 10 is formed of an insulating cylinder made of ceramic or the like. Further, a guide pin 1 is provided along the axis of the cylindrical electrode plate in the concentric part of the cylindrical electrode plates F _{1 to} F _n inside the fixed electrode mounting conductor 13, and this guide is provided on the movable electrode mounting conductor 18 side. A guide portion 5 having a guide pin insertion hole for inserting the pin 1 is provided integrally with the movable lead 2 to form a guide portion, and the guide pin 1 is slidably inserted into the guide portion 5 so that the movable electrode 16 is inserted. It is possible to move by being guided by the guide pin 1, and the withstand voltage and capacitance due to the inclination of the movable lead 2 by moving the movable cylindrical electrode plate while keeping a certain distance from the fixed cylindrical electrode plate. Eliminates instability.
[0005]
The guide portion 5 may be formed integrally with the movable lead 2 or may be provided integrally with or separately from the movable electrode mounting conductor 18. Alternatively, the guide pin 1 may be provided on the movable electrode mounting conductor 18 side, and the guide portion 5 may be provided on the fixed side end plate 13 side.
[0006]
Since the fixed electrode 15 and the movable electrode 16 need to be electrically insulated, the guide pin 1 and the guide portion 5 must be electrically insulated. The insulating means includes the guide pin 1 and the guide portion. Any one of 5 may be made of an insulating material. In order to keep the smoothness of the slidability, it is preferable that the guide pin 1 is made of ceramic, particularly alumina ceramic, and the guide portion 5 is made of phosphor bronze. Means for coating nylon resin with excellent lubricity is also effective.
[0007]
Reference numeral 31 denotes a screw receiving portion. The screw receiving portion 31 is erected on the inner side of the movable side end plate 14, and a collar portion 31a is provided on the inner end portion. Reference numeral 32 denotes a movable lead bolt having a screw threaded on its outer periphery, one end of which is attached to a connecting portion 37 at the distal end of the movable lead 2 shortened, and the other end of the movable lead bolt along the axis inside the flange portion 31a. And projecting into the screw receiving portion 31. Reference numeral 33 denotes an adjustment nut, one end of which is screwed into the end of the movable lead bolt 32 protruding into the screw receiving portion 31, and is rotatably attached to the inner bottom of the flange portion 31a via a bearing 34 such as a bearing. It has been.
[0008]
Reference numeral 19 denotes a bellows, one end of which is brazed to the movable end plate 14, and the other end is brazed to the movable lead 2 or the movable conductor 18. The bellows 19 covers the sliding portion of the movable lead 2 and the penetrating portion of the movable side end plate 14 so that the movable lead 2 can be moved up and down while preventing vacuum leakage.
[0009]
35 is a maximum capacitance adjusting unit, and the maximum capacitance adjusting unit 35 is inside the adjusting nut 33 and is an adjusting screw 36 that is screwed into a screw hole provided at the tip of the movable lead bolt 32; A large-diameter portion 33a and a step portion 33b are formed inside the adjustment nut 33 so that the adjustment screw 36 is inserted.
[0010]
Reference numeral 40 denotes a drive motor, and a belt 42 for transmitting a rotational force is attached between the adjusting nut 33 and a sprocket 41 fixed to the output shaft 40a of the drive motor 40.
[0011]
According to such a vacuum capacitor, when adjusting the maximum capacitance value, first, the adjustment nut 33 is slightly turned to the right before the adjustment screw 36 is screwed into the tip of the movable lead bolt 32 and fixed (right In the case of a screw), the movable lead 2 is slightly moved downward from the position of the maximum capacitance where the tip 1a of the guide pin 1 and the end face of the connecting portion 37 of the movable lead bolt 32 abut, and the defined maximum capacitance value Adjust to. This slight adjustment amount is determined by the degree of variation in the capacitance of the vacuum capacitor.
[0012]
In this state, the adjusting screw 36 is screwed in until the contact surface of the head comes into contact with the stepped portion 33b. When the adjusting screw 36 comes into contact, the adjusting screw 36 is fixed to the movable lead bolt 32 with an adhesive or the like. The rising position is regulated (not adhered to the adjusting nut 33). By regulating the rising position of the movable lead bolt 32 in this way, the maximum capacitance value can be adjusted and defined for each vacuum capacitor even if the maximum capacitance value of manufactured vacuum capacitors varies. A vacuum capacitor with a quality that matches the maximum capacitance value can be obtained.
[0013]
The electrostatic capacitance value of the vacuum capacitor is adjusted by rotating the adjustment nut 33 left and right by the action of the drive motor 40. For example, the movable lead bolt 32 moves downward in the right rotation and moves upward in the left rotation. The movable electrode 16 moves up and down, and the total area facing the fixed electrode 15 can be varied to arbitrarily adjust the capacitance. Even if the adjustment nut 33 is turned counterclockwise from the position of the maximum capacitance value, the adjustment screw 36 hits the step portion 33b and does not turn any further to the left. Therefore, the adjustment screw 36 is pulled out of the movable lead bolt. It also has a stopper function to prevent this.
[0014]
[Problems to be solved by the invention]
As described above, when adjusting the capacitance value of the vacuum capacitor, the rotational force of the drive motor 40 is transmitted to the adjustment nut 33 via the sprocket 41 and the belt 42 fixed to the output shaft 40a. The electrode 16 moves up and down to change the total area facing the fixed electrode 15 and can be arbitrarily adjusted. In such an operation, the adjustment nut 33 has a lateral direction in the drawing, that is, the adjustment nut. Since a force in a direction perpendicular to the rotation axis 33 is applied, there is a problem that a “blurring” phenomenon occurs in which the adjustment nut 33 moves laterally due to this external force.
[0015]
That is, since there is some backlash between the threaded portions of the adjustment nut 33 and the movable lead bolt 32, the rotation axis of the adjustment nut 33 and the axis of the movable lead bolt 32 may be shifted when the adjustment nut 33 moves in the lateral direction. Yes, if the adjustment nut 33 is further rotated in such a state, the friction of the screw portion increases and the torque required for the rotation of the adjustment nut 33 increases, or the screw portion “galling” or the like occurs. Life is likely to decrease.
[0016]
When such a lateral force is relatively large, not only the adjustment nut 33 is moved, but also a lateral force is applied from the adjustment nut 33 to the movable lead 2 via the movable lead bolt 32. 5 and the guide pin 1 increase in friction, which may increase the torque required for the adjustment nut 33 to rotate. Further, since there is some tolerance between the guide part 5 and the guide pin 1, the guide part 5 moves by a tolerance distance in the direction in which the force is received, and accordingly, the cylindrical electrode plates M ₁ and M ₂ on the movable side are moved. , · · · · Mn also the distance between the cylindrical electrode plate F _1, F ₂ ···· F _n of the fixed side is shortened by moving in the same direction, resulting a problem that the withstand voltage is lowered.
[0017]
The present invention has been made in view of the above points, and even when the adjustment nut is rotated when adjusting the capacitance value of the vacuum capacitor, a lateral force is not applied to the adjustment nut. As a result, the rotation of the adjustment nut and the shaft of the movable lead bolt are prevented from being displaced, and the increase in the rotation torque of the adjustment nut due to increased friction of the screw is prevented. An object of the present invention is to provide a vacuum capacitor in which the life of components is not reduced.
[0018]
In order to achieve the above object, the present invention has a vacuum vessel having a fixed side end plate on one end side of a cylindrical portion and a movable side end plate on the other end side, and a concentric circle in the vacuum vessel. A fixed electrode formed by attaching a plurality of cylindrical electrode plates having different diameters to a fixed electrode mounting conductor, and a plurality of cylindrical shapes having different diameters so that they can be inserted / removed in a non-contact state between the cylindrical electrode plates of the fixed electrode A movable electrode formed by attaching an electrode plate to a movable electrode mounting conductor, a movable lead for moving the movable electrode from the outside of the movable side end plate of the vacuum vessel in the axial direction of the cylindrical electrode plate, and an outer periphery of the movable lead Provided on the inner side of the movable side end plate and at the center of the opposing surfaces of the fixed electrode mounting conductor and the movable electrode mounting conductor, the bellows enabling movement of the movable lead while maintaining a vacuum state Each guide pin and this guy A guide portion for electrically slidably inserting a pin, a movable lead bolt attached in an axial direction to the distal end portion of the movable lead, and a screw protruding into the bellows inside the movable side end plate A vacuum capacitor comprising a receiving portion, and an adjusting nut supported by the screw receiving portion and a bearing and screwed to the movable lead bolt, and adjusting a capacitance of the capacitor by rotating the adjusting nut In
A needle bearing is disposed between the adjustment nut and the screw receiving portion .
[0019]
Further, according to claim 2, a vacuum vessel having a fixed side end plate on one end side of the cylindrical portion and a movable side end plate on the other end side, and a plurality of concentric cylinders having different diameters in the vacuum vessel A fixed electrode formed by attaching a cylindrical electrode plate to a fixed electrode mounting conductor, and a plurality of cylindrical electrode plates with different diameters attached to each cylindrical electrode plate of this fixed electrode so that they can be inserted and removed without contact A movable electrode attached to a conductor, a movable lead for moving the movable electrode from the outside of the movable side end plate of the vacuum vessel in the axial direction of the cylindrical electrode plate, and the movable side end on the outer peripheral side of the movable lead A bellows provided on the inner side of the plate and capable of moving the movable lead while maintaining a vacuum state, and a guide pin provided at the center of the opposing surface of the fixed electrode mounting conductor and the movable electrode mounting conductor, respectively. And this guide pin electrically A guide portion that is slidably inserted at the edge, a movable lead bolt that is attached to the distal end portion of the movable lead in the axial direction, a screw receiving portion that projects into the bellows inside the movable side end plate, and In a vacuum capacitor comprising a screw receiving portion and an adjustment nut supported through a bearing and screwed to the movable lead bolt, and adjusting the capacitance of the capacitor by rotating the adjustment nut;
A needle bearing mounting bracket having an inner peripheral flange portion is fixed to the lower surface of the movable side end plate, and the needle bearing is disposed between the inner peripheral flange portion of the needle bearing mounting bracket and the adjustment nut. It is characterized by.
According to a third aspect of the present invention, there is provided a vacuum vessel having a fixed side end plate on one end side of the cylindrical portion and a movable side end plate on the other end side, and a plurality of concentric and different diameters in the vacuum vessel. A fixed electrode formed by attaching a cylindrical electrode plate to a fixed electrode mounting conductor, and a plurality of cylindrical electrode plates having different diameters so that they can be inserted and removed in a non-contact state between the cylindrical electrode plates of the fixed electrode A movable electrode attached to the mounting conductor, a movable lead for moving the movable electrode from the outside of the movable side end plate of the vacuum vessel in the axial direction of the cylindrical electrode plate, and the movable side on the outer peripheral side of the movable lead A bellows provided inside the end plate and capable of moving the movable lead while maintaining a vacuum state, and a guide provided at the center of the opposing surfaces of the fixed electrode mounting conductor and the movable electrode mounting conductor, respectively. Electrically disconnect the pin and this guide pin A slidably inserted guide portion, a movable lead bolt attached in the axial direction to the tip of the movable lead, a screw receiving portion protruding into the bellows inside the movable side end plate, and the screw In a vacuum capacitor that is supported via a receiving portion and a bearing and includes an adjustment nut that is screwed to the movable lead bolt, and the capacitance of the capacitor is adjusted by rotating the adjustment nut.
An outer conductor having an inner peripheral flange portion is fixed to the lower surface of the movable side end plate, and a needle bearing is disposed between the inner peripheral flange portion of the outer conductor and the adjustment nut. Is .
[0020]
According to such a vacuum capacitor, the needle bearing provided in a state of being fitted between the adjusting nut and the screw receiving portion receives a lateral force applied to the adjusting nut, and the “blurring” phenomenon of the adjusting nut caused by an external force. Since the rotating shaft of the adjusting nut and the shaft of the movable lead bolt are held in alignment, there is no increase in the rotating torque of the adjusting nut due to an increase in friction of the screw portion. A reduction in the withstand voltage due to a decrease in the service life of the component or a tolerance existing between the guide portion and the guide pin is prevented.
[0021]
According to the second aspect of the present invention, the needle bearing mounting bracket is fixed to the lower surface of the movable side end plate, so that the degree of freedom in design is widened. By fixing the outer conductor directly to the lower surface, an effect of simplifying the configuration can be obtained.
[0022]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, various embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing a first embodiment of the present invention, which is shown as a longitudinal front view in the illustrated example. The same components as those in FIG. 4 are denoted by the same reference numerals.
[0023]
Reference numeral 12 denotes an insulating cylinder such as ceramic. Copper cylinders 11a and 11b are joined to both ends of the insulating cylinder 12 to form a cylindrical portion. The cylindrical portion is formed into a fixed electrode mounting conductor 13 and a movable side end plate 14. The vacuum vessel 10 is closed and accommodates the capacitor portion. Inside the fixed electrode mounting conductor 13, a plurality of concentric cylindrical electrode plates F ₁ , F ₂ ... F _n having different diameters (radius) are mounted at a constant interval to form the fixed electrode 15. . In the gap of the electrode plates of the fixed electrode 15, a plurality of different cylindrical electrode plates M _1, M ₂ ···· M _n inner diameter to allow interpolation and from the movable electrode mounting conductor 18 in a non-contact state The movable electrode 16 is formed.
[0024]
A guide pin 1 is provided along the axis of the cylindrical electrode plate in the concentric part of the cylindrical electrode plates F _{1 to} F _n inside the fixed electrode mounting conductor 13, and the guide pin 1 is provided on the movable electrode mounting conductor 18 side. A guide portion 5 having a guide pin insertion hole for inserting a guide pin is provided integrally with the movable lead 2 to form a guide portion, and the guide pin 1 is slidably inserted into the guide portion 5 to insert the movable electrode 16 into the guide pin. 1 is movable by being guided, and the movable side cylindrical electrode plate is moved while keeping a certain distance from the fixed side cylindrical electrode plate. It is lost. The guide pin 1 may be provided on the movable electrode mounting conductor 18 side, and the guide portion 5 may be provided on the fixed side end plate 13 side.
[0025]
Reference numeral 31 denotes a screw receiving portion. The screw receiving portion 31 is erected on the inner side of the movable side end plate 14, and a collar portion 31a is provided on the inner end portion. Reference numeral 32 denotes a movable lead bolt having a screw threaded on its outer periphery, one end of which is attached to a connecting portion 37 at the distal end of the movable lead 2 shortened, and the other end of the movable lead bolt along the axis inside the flange portion 31a. And projecting into the screw receiving portion 31. Reference numeral 33 denotes an adjustment nut, one end of which is screwed into the end of the movable lead bolt 32 protruding into the screw receiving portion 31, and is rotatably attached to the inner bottom of the flange portion 31a via a bearing 34 such as a bearing. It has been.
[0026]
Reference numeral 19 denotes a bellows, one end of which is brazed to the movable end plate 14, and the other end is brazed to the movable lead 2 or the movable conductor 18. The bellows 19 covers the sliding portion of the movable lead 2 and the penetrating portion of the movable side end plate 14 so that the movable lead 2 can be moved up and down while preventing vacuum leakage.
[0027]
Inside the adjustment nut 33, an adjustment screw 36 that is screwed into a screw hole provided at the tip of the movable lead bolt 32, and a large-diameter portion formed inside the adjustment nut 33 so that the adjustment screw 36 is inserted. 33a and step 33b are formed.
[0028]
In this embodiment, the needle bearing 45 is fitted between the adjusting nut 33 and the screw receiving portion 31.
[0029]
Reference numeral 40 denotes a drive motor, and a belt 42 that transmits a rotational force is attached between a sprocket 41 fixed to an output shaft 40 a of the drive motor 40 and the adjustment nut 33.
[0030]
According to such a vacuum capacitor, when adjusting the maximum capacitance value, the adjustment nut 33 is slightly turned to the right before the adjustment screw 36 is screwed into and fixed to the tip of the movable lead bolt 32 (right screw). In this case, the movable lead 2 is moved slightly downward from the position of the maximum capacitance where the tip 1a of the guide pin 1 and the end surface of the connecting portion 37 of the movable lead bolt 32 abut, and the defined maximum capacitance value is obtained. Adjust. This slight adjustment amount is determined by the degree of variation in the capacitance of the vacuum capacitor.
[0031]
In this state, the adjusting screw 36 is screwed in until the contact surface of the head comes into contact with the stepped portion 33b. When the adjusting screw 36 comes into contact, the adjusting screw 36 is fixed to the movable lead bolt 32 with an adhesive or the like. Regulate the ascending position.
[0032]
The electrostatic capacitance value of the vacuum capacitor is adjusted by transmitting the rotational force of the drive motor 40 from the output shaft 40a to the adjustment nut 33 via the belt 42, and rotating the adjustment nut 33 left and right to move the movable lead bolt 32. The movable electrode 16 moves up and down to move up and down, the total area facing the fixed electrode 15 changes, and the capacitance can be adjusted arbitrarily.
[0033]
At this time, the needle bearing 45 disposed in a state of being fitted between the adjustment nut 33 and the screw receiving portion 31 receives a lateral force applied to the adjustment nut 33, and “blurring” of the adjustment nut 33 due to external force. The phenomenon can be prevented, and the rotating shaft of the adjusting nut 33 and the shaft of the movable lead bolt 32 can be held in the same state. Accordingly, there is no increase in the rotational torque of the adjusting nut 33 due to the increase in friction of the threaded portion. Can be prevented.
[0034]
FIG. 2 is an enlarged view of an essential part showing a second embodiment of the present invention. In this example, a needle bearing mounting bracket 46 is fixed to the lower surface of the movable side end plate 14, and the inner peripheral side of the needle bearing mounting bracket 46 is shown. A needle bearing 45 is fitted between the flange portion 46a and the adjusting nut 33. Reference numeral 47 denotes an outer conductor fixed to the needle bearing mounting bracket 46. The outer conductor 47 may be directly fixed to the needle bearing mounting bracket 46 as shown in the drawing, or may be inserted and fixed between the movable side end plate 14 and the needle bearing mounting bracket 46.
[0035]
The basic operation of the second embodiment is the same as that of the first embodiment. However, the needle bearing mounting bracket 46 is fixed to the lower surface of the movable side end plate 14 as compared with the first embodiment, so that the design is improved. There is an advantage that the degree of freedom is expanded.
[0036]
FIG. 3 is an enlarged view of an essential part showing a third embodiment of the present invention. In this example, an outer conductor 47 is directly fixed to the lower surface of the movable side end plate 14, and an inner peripheral flange 47a of the outer conductor 47 is shown. And the adjustment nut 33 are arranged in a state in which the needle bearing 45 is fitted.
[0037]
The basic operation of the third embodiment is the same as that of the first embodiment, but there is an advantage that the configuration is simplified by fixing the external conductor 47 directly to the lower surface of the movable side end plate 14.
[0038]
【The invention's effect】
As described in detail above, the vacuum capacitor according to the present invention is provided between the adjusting nut and the screw receiving portion when the adjusting nut is rotated using the rotational force of the drive motor or the like when adjusting the capacitance value. The needle bearing deployed in a state where it is fitted to the side receives the lateral force applied to the adjustment nut and prevents the "blurring" phenomenon, so that the rotation axis of the adjustment nut and the axis of the movable lead bolt are held in alignment. As a result, there is no increase in the rotational torque of the adjusting nut due to increased friction of the screw part, and the life of the parts is reduced due to `` galling '' of the screw part or the withstand voltage due to the tolerance existing between the guide part and the guide pin. The decrease phenomenon can be prevented.
[0039]
In particular, when the lateral force is relatively large, the lateral force is also applied to the movable lead from the adjustment nut via the movable lead bolt, increasing the friction between the guide portion and the guide pin, resulting in the torque required for rotation of the adjustment nut. However, according to the present invention, it is possible to obtain the effect of reliably eliminating the above-mentioned difficulties.
[0040]
Furthermore, according to the configuration of claim 2, the degree of freedom in design is widened by fixing the needle bearing mounting bracket to the lower surface of the movable side end plate. By fixing the outer conductor directly to the lower surface, an effect that the configuration is simplified can be obtained.
[0041]
In addition, the maximum capacitance value of the manufactured vacuum capacitor can be easily adjusted and can match the defined maximum capacitance value. A vacuum capacitor having a maximum capacitance value can be obtained.
[Brief description of the drawings]
FIG. 1 is a configuration diagram showing a first embodiment of the present invention.
FIG. 2 is an enlarged view of a main part of a second embodiment of the present invention.
FIG. 3 is an enlarged view of a main part of a third embodiment of the present invention.
FIG. 4 is a basic configuration diagram of a vacuum capacitor to which the present invention is applied.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Guide pin 2 ... Movable lead 5 ... Guide part 10 ... Vacuum vessel 13 ... Fixed electrode attachment conductor 11a, 11b ... Cylindrical tube 12 ... Insulating inner cylinder 14 ... Movable side end plate 15 ... Fixed electrode 16 ... Movable electrode 18 ... Movable Electrode mounting conductor 19 ... Bellows 31 ... Screw receiving portion 32 ... Movable lead bolt 33 ... Adjustment nut 34 ... Bearing 36 ... Adjustment screw 37 ... Connection portion 40 ... Drive motor 45 ... Needle bearing 46 ... Needle bearing mounting bracket 47 ... External conductor 46a 47a ... Flange

Claims

A vacuum vessel having a fixed end plate on one end side of the cylindrical portion and a movable end plate on the other end side, and a plurality of concentric cylindrical electrode plates having different diameters in the vacuum vessel are fixed electrodes. A fixed electrode formed by attaching to a mounting conductor and a plurality of cylindrical electrode plates having different diameters attached to the movable electrode mounting conductor so that they can be inserted and removed in a non-contact state between the cylindrical electrode plates of the fixed electrode. A movable electrode; a movable lead that moves the movable electrode in the axial direction of the cylindrical electrode plate from the outside of the movable side end plate of the vacuum vessel; and an inner side of the movable side end plate on an outer peripheral side of the movable lead. , A bellows capable of moving the movable lead in a vacuum state, a guide pin provided at the center of the opposing surface of the fixed electrode mounting conductor and the movable electrode mounting conductor, and the guide pin Insulatively and slidably inserted A guide portion for the movable lead bolt mounted axially distal end portion of the movable lead screw receiving portion projecting into the bellows inside the movable-side end plate, and through the screw receiving portion and the bearing A vacuum capacitor that is supported and includes an adjustment nut that is screwed onto the movable lead bolt, and that adjusts the capacitance of the capacitor by rotating the adjustment nut;
Between the screw receiving part and the adjustment nut, vacuum capacitor, characterized in that arranged the needle bearings.

A vacuum vessel having a fixed end plate on one end side of the cylindrical portion and a movable end plate on the other end side, and a plurality of concentric cylindrical electrode plates having different diameters in the vacuum vessel are fixed electrodes. A fixed electrode formed by attaching to a mounting conductor and a plurality of cylindrical electrode plates having different diameters attached to the movable electrode mounting conductor so that they can be inserted and removed in a non-contact state between the cylindrical electrode plates of the fixed electrode. A movable electrode; a movable lead that moves the movable electrode in the axial direction of the cylindrical electrode plate from the outside of the movable side end plate of the vacuum vessel; and an inner side of the movable side end plate on an outer peripheral side of the movable lead. , A bellows capable of moving the movable lead in a vacuum state, a guide pin provided at the center of the opposing surface of the fixed electrode mounting conductor and the movable electrode mounting conductor, and the guide pin Insulatively and slidably inserted Through the guide portion, the movable lead bolt attached to the tip of the movable lead in the axial direction, the screw receiving portion protruding into the bellows inside the movable side end plate, and the screw receiving portion and the bearing A vacuum capacitor that is supported and includes an adjustment nut that is screwed onto the movable lead bolt, and that adjusts the capacitance of the capacitor by rotating the adjustment nut;
A needle bearing mounting bracket having an inner peripheral flange portion is fixed to the lower surface of the movable side end plate, and the needle bearing is disposed between the inner peripheral flange portion of the needle bearing mounting bracket and the adjustment nut. Vacuum capacitor characterized by

A vacuum vessel having a fixed end plate on one end side of the cylindrical portion and a movable end plate on the other end side, and a plurality of concentric cylindrical electrode plates having different diameters in the vacuum vessel are fixed electrodes. A fixed electrode formed by attaching to a mounting conductor and a plurality of cylindrical electrode plates having different diameters attached to the movable electrode mounting conductor so that they can be inserted and removed in a non-contact state between the cylindrical electrode plates of the fixed electrode. A movable electrode; a movable lead that moves the movable electrode in the axial direction of the cylindrical electrode plate from the outside of the movable side end plate of the vacuum vessel; and an inner side of the movable side end plate on an outer peripheral side of the movable lead. , A bellows capable of moving the movable lead in a vacuum state, a guide pin provided at the center of the opposing surface of the fixed electrode mounting conductor and the movable electrode mounting conductor, and the guide pin Insulatively and slidably inserted Through the guide portion, the movable lead bolt attached to the tip of the movable lead in the axial direction, the screw receiving portion protruding into the bellows inside the movable side end plate, and the screw receiving portion and the bearing A vacuum capacitor that is supported and includes an adjustment nut that is screwed onto the movable lead bolt, and that adjusts the capacitance of the capacitor by rotating the adjustment nut;
The lower surface of the movable-side end plate, and secured to the outer conductor having an inner peripheral side flange portion, characterized in that disposed a needle bearing between the adjusting nut and the inner flange portion of the outer conductor Vacuum capacitor.