JP4360013B2

JP4360013B2 - Circuit breaker

Info

Publication number: JP4360013B2
Application number: JP2000192293A
Authority: JP
Inventors: 孝夫三橋; 満月間; 征浩伏見
Original assignee: Mitsubishi Electric Corp
Current assignee: Mitsubishi Electric Corp
Priority date: 2000-06-27
Filing date: 2000-06-27
Publication date: 2009-11-11
Anticipated expiration: 2020-06-27
Also published as: JP2002008508A

Description

【０００１】
【発明の属する技術分野】
この発明は、短絡電流により平行導体間に発生する電磁力を利用して接触子を開離させる回路遮断器に関するものである。
【０００２】
【従来の技術】
図１４は例えば特公昭６２−２４２３号公報に示された従来の回路遮断器を示す部分断面図であり、図において、１は可動接点２が一端に固着された可動接触子、５は可動接点２と接点対をなす固定接点６を有する固定接触子であり、端子部１５ａにて電源回路と接続される。閉路状態では、上記可動接触子１と固定接触子５は、上下にわずかな間隔で重合し互いに平行に保持されている。１３は消弧側板１４にて保持された複数の消弧板、２５は可動接触子１を開閉動作させる機構部、２９は機構部２５を手動にて操作するためのハンドルである。これらの構成部品は、カバー２８とベース２７からなる筐体にて収納される。
【０００３】
次に動作について説明する。通常通電時の開閉では、ハンドル２９の操作にて機構部２５が動作し、可動接触子１が回動して開閉される。一方、閉路状態で短絡電流等の大電流が流れた場合、可動接触子と固定接触子に流れる逆方向電流による電磁反発力によって上記機構部に無関係に接触子が開離し、続いて過電流に応答して引外し機構（図示せず）の作動により、機構部２５を遮断状態に駆動する。従って、事故発生直後の早い時期に、接点２、６間にアークを発生させ、このアークを急速に引き延ばすことができ、接点間のアーク電圧は素早く立ち上がる。このアーク電圧により事故電流が限流される。続いて、電流瞬時値が低下すると、アークは鉄製の消弧板１３に引き込まれて分断、冷却され、消弧されるので、電流が遮断される。
【０００４】
このような図１４に示す回路遮断器においては、固定接触子５は、閉路状態において可動接触子１と対向し平行且つ逆方向電流が流れる平行導体部７ａを確保するために略Ｕ状に折り曲げられ、可動接触子と対向する先端部に固定接点６が固着されている。このような固定接触子においては、可動接触子１に電磁吸引力を発生させる逆平行導体部７ｂを流れる電流の影響を小さくするため、また折曲げ加工時の金型の制約から垂直導体部７ｅの高さを小さくできず回路遮断器の高さ方向の小形化が難しく、さらには固定接触子の導体が長くなり部品コスト高になるという欠点もあった。
【０００５】
そこで、上記公報に開示された別の従来の回路遮断器では、図１５に示す固定接触子構造にて回路遮断器の高さ方向の小形化を図っている。図１５において、固定接触子５は可動接触子１（図示しない）と対向する部分に、その先端側５ｂから基端側５ａに向かって延びる舌片を形成するようにコ字形の抜穴３６が設けられている。上記舌片は、閉路状態の可動接触子と平行且つ逆方向電流が流れる平行導体部７ａとその一端部に固着された固定接点６にて形成されており、閉路状態の可動接触子と平行且つ同方向電流が流れる逆平行導体部７ｂが上記平行導体部７ａと同一高さに配置され、図１４の垂直導体部７ｅのように、上下方向に延びる導体は存在しない。従って、回路遮断器の高さ方向の寸法を小さくでき、ユーザの使い勝手が良くなる。また、固定接触子の製造に曲げ加工を用いる必要が無くなり、加工性が向上する。
【０００６】
【発明が解決しようとする課題】
従来の回路遮断器では、閉路状態の可動接触子と平行且つ逆方向電流が流れて電磁反発力を発生させる平行導体部とそれ以外の固定接触子を形成する電路とが同一高さに配置されることにより、高さ寸法を小さくすることができたが、閉路状態の可動接触子と平行且つ同方向電流が流れて可動接触子に対して電磁吸引力を発生させる逆平行導体部が存在するので、短絡事故時の可動接触子の開極速度を十分に上げることができない。特に、回路遮断器の幅方向（可動接触子が延びる方向に垂直な方向）の寸法に制限がある場合、逆平行導体部を平行導体部と同一高さに配置することにより、逆平行導体部を流れる電流により発生する可動接触子を電磁吸引する力が、図１４に示した略Ｕ字状の固定接触子を用いた場合より大きくなることがあり、可動接触子の開極速度が低下して十分な限流性能が得られないと言う問題点があった。
【０００７】
また、逆平行導体部を流れる電流が発生する磁界成分は、平行導体部を流れる電流が発生するアークを消弧板へと引き延ばす磁界成分を打ち消し、接点間に発生したアークが消弧板にて分断、冷却され難くなる。これにより、遮断時間が長くなって消弧室構成部品の損耗が増大したり、最悪の場合は、遮断不能となると言う問題点があった。
【０００８】
この発明は、上記のような問題点を解消するためになされたものであり、回路遮断器の高さ方向の寸法を小さくした遮断器においても、限流性能に優れた回路遮断器を得ることを目的とするものである。
【０００９】
【課題を解決するための手段】
この発明に係る回路遮断器においては、固定接触子が、固定接点を一端部に有して閉成状態の可動接触子と略平行且つ逆方向電流が流れる平行導体部と、一端部にて上記平行導体と接続され且つ上記平行導体部の左右両側に配置されて閉成状態の上記可動接触子と略平行且つ同方向電流が流れる逆平行導体部とを有するようにし、上記逆平行導体部の上記可動接触子側に上記可動接触子の可動接点側の一端部を左右より挟み込むように一対の磁性体板を配置し、上記一対の磁性体板を構成する各磁性体板間の間隔より、上記各磁性体板と上記可動接触子の一端部に対向して設けられた磁性体の消弧板との夫々の間隔が小さくなるようにしたものである。
【００１０】
また、平行導体部の一端部にはアークランナが延設され、可動接点が固定接点から開離する方向を上方としたとき、固定接触子は、逆平行導体部の他端部から上方向に延びて端子部と接続される接続導体垂直部を有し、この接続導体垂直部には、可動接触子の開閉動作時の軌跡を含む面と交わる部位にスリットが設けられており、このスリットの左右の接続導体垂直部を構成する一対の導体部に一対の磁性体板が各々対向するようにしたものである。
【００１１】
また、平行導体部の一端部にはアークランナが延設され、可動接点が固定接点から開離する方向を上方としたとき、固定接触子は、逆平行導体部の他端部から上方向に延びて端子部と接続される接続導体垂直部を有し、この接続導体部の固定接点側の前面に磁性体の遮蔽板を配置したものである。
【００１２】
また、接続導体垂直部には、可動接触子の開閉動作時の軌跡を含む面と交わる部位にスリットが設けられており、このスリットの左右の接続導体垂直部を構成する一対の導体部の固定接点側の前面に磁性体の一対の遮蔽板を各々配置したものである。
【００１３】
また、平行導体部の一端部にはアークランナが延設され、このアークランナの先端部は、一対の磁性体板に囲まれる空間外にあり、可動接点が固定接点から開離する方向を上方としたとき、上記アークランナの先端部の上部空間に磁性体の消弧板が配置されたものである。
【００１４】
また、固定接触子は、逆平行導体部の他端部から上方向に延びて端子部と接続される接続導体垂直部を有し、複数の磁性体の消弧板の内の一部の消弧板が上記接続導体垂直部と一対の磁性体板の間に配置されたものである。
【００１５】
また、平行導体部の一端部にはアークランナが延設され、且つ、絶縁カバーの固定接点の直ぐ横より平行導体部の他端部側にかけての部位に突起部を設け、上記突起部に囲まれる空間が、上記アークランナ側に広がるラッパ状となるようにしたものである。
【００１６】
また、平行導体部の一端部にはアークランナが延設され、且つ、絶縁カバーの固定接点の直ぐ横から平行導体部の他端部側にかけての部位を、その他の部位よりアークの熱により多量の蒸気を発生する物質にて形成したものである。
【００１７】
また、平行導体部の一端部にはアークランナが延設され、このアークランナ、可動接触子、固定接触子、一対の磁性体板および磁性体の消弧板は筐体にて収納され、この筐体内面と上記一対の磁性体板の反可動接触子側の面との間に、上記アークランナの先端部近傍の空間より連通する流路が形成されるようにしたものである。
【００１８】
また、複数の極を有し、各極ごとに一対の磁性体板を形成する磁性体片の内、極間側の磁性体片を隣り合う他極の磁性体片と一体にしたものである。
【００１９】
【発明の実施の形態】
実施の形態１．
図１は、この発明の実施の形態１による回路遮断器を説明するための図であり、より具体的には開成状態の消弧ユニット部分の部分断面斜視図である。また、図２は、この消弧ユニット内に配置される主要部の部品展開図である。図３は、図１に示した消弧ユニットを用いて構成される回路遮断器の構成を示す展開図である。
【００２０】
図１において、１は一端部に可動接点２（図示せず）が固着された可動接触子、５は上記可動接触子１と接触子対を形成する固定接触子である。１０は略Ｌ字状の一対の磁性体板であり、上記可動接触子１を左右から挟み込むように配置されており、可動接触子１側の面を絶縁カバー１２により覆われている。１３は消弧側板１４に保持された磁性体からなる複数の馬蹄形の消弧板である。１７は可動接触子１に接触圧を発生させるバネであり、一端部をバネ掛け１８にて保持されている。１６は端子部１５ｃと可動接触子１とを電気的に接続する摺動接触子、１９は機構部２５（図示せず）の動きをクロスバ２４（図示せず）を介して可動接触子１へ伝えるロータであり、このロータの内部構造が分かるように断面をとっている。これらの消弧ユニットを形成する部品は、消弧ユニット筐体本体２１と消弧ユニット筐体蓋２２にて収納される。
【００２１】
図２において、上記消弧ユニット内部の主要部品構成をさらに詳細に説明すると、固定接触子５は、固定接点６が固着された舌片を有しており、この舌片は閉路状態の可動接触子１と略平行且つ逆方向の電流が流れる平行導体部７ａと固定接点６から反ロータ１９側へと延びるアークランナ９を有している。平行導体部７ａはロータ１９側で逆平行導体部７ｂの一端部と接続され、逆平行導体部７ｂは平行導体部７ａの左右に略同一高さで配置されており、逆平行導体部７ｂの他端部は、上下方向に延びる接続導体垂直部７ｃと前後方向に延びる接続導体平行部７ｄを介して端子部１５ａに接続される。接続導体垂直部７ｃと接続導体平行部７ｄには、可動接触子１の回動の軌跡を含む面に沿ったスリット８が設けられている。固定接触子５の逆平行導体部７ｂの上部には絶縁シート１１にて固定接触子と電気的に絶縁された状態の一対の磁性体板１０が可動接触子１の可動接点２側端部を挟み込むように配置され、接点間に発生するアークに暴露される上記一対の磁性体板１０の内面とロータ側端面と消弧板１３側端面とが絶縁カバー１２にて覆われている。
【００２２】
上記一対の磁性体板は可動接触子１の左右にて上下方向に延びる第１の磁性体板の部位１０ａと逆平行導体部７ｂに沿って延び、一端面が接続導体垂直部７ｃと対向している第２の磁性体板の部位１０ｂにて、各々略Ｌ字状となっている。上記絶縁カバー１２は、上記一対の磁性体板を覆う第１の絶縁カバーの部位１２ａと、平行導体部７ａの上面を覆う第２の絶縁カバーの部位１２ｂと、接続導体７ｃ、７ｄを覆う第３の絶縁カバーの部位１２ｃにて一体に形成されている。この絶縁カバーの上に、消弧側板１４にて保持された複数の磁性体消弧板１３が配置される。上記消弧板の形状は可動接触子１側に切欠き部を有する馬蹄形である。また、可動接触子１は、可動子回転軸４にて回動自在に保持されており、機構部２５（図示せず）の動きをロータ１９を介して伝えられる構成となっている。このロータ１９には、クロスバー２４（図示せず）連通用の貫通穴が設けられている。このような消弧室ユニット２３を、図３に示すように、複数個クロスバー２４にてロータ連通し、このクロスバーと機構部２５を係合させ、これらと回路の異常を検知して上記機構部を駆動するリレー部２６とハンドル２９とを、カバー２８とベース２７とからなる筐体にて収納すれば、回路遮断器が構成される。
【００２３】
次に動作について説明する。通常通電時の開閉では、ハンドル２９の操作にて機構部２５が動作し、可動接触子１が回動して開閉される。一方、閉路状態で短絡電流等の大電流が流れた場合、可動接触子と固定接触子に流れる逆方向電流による電磁反発力によって上記機構部に無関係に接触子が開離し、続いて過電流に応答してリレー部２６の作動により、機構部２５を遮断状態に駆動する。従って、事故発生直後の早い時期に、接点２、６間にアークを発生させ、このアークを急速に引き延ばすことができ、接点間のアーク電圧は素早く立ち上がる。このアーク電圧により事故電流が限流される。続いて、電流瞬時値が低下すると、アークは鉄製の消弧板１３に引き込まれて分断、冷却され、消弧されるので、電流が遮断される。これらの遮断動作は基本的に上記従来の回路遮断器と同様である。また、閉路状態の可動接触子と平行且つ逆方向電流が流れる平行導体部７ａと、閉路状態の可動接触子と平行且つ同方向電流が流れる逆平行導体部７ｂが上記電路７ａと同一高さに配置されることにより、回路遮断器の高さ方向の寸法を小さくでき、ユーザの使い勝手が良くなること、および、固定接触子の製造に曲げ加工を用いる必要が無くなり加工性が向上することも上記別の従来の回路遮断器と同様である。
【００２４】
しかしながら本実施の形態では、上記別の従来の回路遮断器と異なり、逆平行導体部７ｂ上部に略Ｌ字状の一対の磁性体板１０を配置しており、この一対の磁性体板と磁性体消弧板１３にて磁気回路を形成し、逆平行導体部７ｂの電流が発生する磁界成分が可動接触子１および接点間に発生したアークに作用するのを防止するとともに、上記可動接触子およびアークの駆動を促進している。
【００２５】
図４および図５は、本実施の形態での可動接触子１、固定接触子５、一対の磁性体板１０および消弧板１３の位置関係を模式的に示す説明図である。図４は閉路状態を、図５は遮断動作途中の可動接触子が最大開極した状態を夫々示している。図５（ａ）は、図５（ｂ）を上方より見た図である。また、図４および図５（ｂ）中には、白抜き矢印にて電流の流れを夫々示している。図５（ａ）に示す様に、逆平行導体部７ｂの上部に設けられた一対の磁性体板１０の間隔Ｗは、一対の磁性体板１０と消弧板１３との間隙ｄ１より大きく配置されている。
【００２６】
このような構成とすると、図４に示した閉路状態において、逆平行導体部７ｂを流れる電流が発生する磁束（可動接触子１の開極を妨げる磁界成分）は、一対の磁性体板１０および消弧板１３がつくる磁気回路を通るため、可動接触子１には作用しなくなる（可動接触子１は逆平行導体部７ｂを流れる電流がつくる磁界成分から遮蔽される）。さらに、閉路状態の可動接触子１は、一対の磁性体板１０と消弧板１３にて形成される略Ｕ字状の磁性体に囲まれる空間内に位置しているので、上記磁性体による吸引力が働き、開極速度が向上する（言い換えれば、限流性能が向上する）。
【００２７】
同様に、図５（ｂ）に示すように、接点間に発生したアークにも上記逆平行導体部７ｂを流れる電流が発生する磁界は作用しなくなり、アークは平行導体部７ａの電流がつくる磁界によりアークランナ９へと押しだされる。さらに、アークは、一対の磁性体板１０と消弧板１３にて形成される略Ｕ字状の磁性体に囲まれる空間内に位置しており、疑似的に馬蹄形消弧板の足の部分（消弧板の切欠き部左右の部分）が可動接触子１側へと延びた構成と等価となるので、アークに働く消弧板１３への吸引力が向上する。この吸引力の向上により、アークが消弧板にて分断、冷却される時点が早くなるので、遮断時間の短縮が図れ、消弧室の損耗低減につながる。また、アーク時間が長くなることによりホットガスが充満して遮断不能となることを防げる。
【００２８】
ところで、回路遮断器の端子部は電線との接続ネジ等の関係から取付面より高い位置に設けられるのが一般的である。一方、固定接点６は、筐体内部空間を最大限利用して回路遮断器の高さ方向を小さくするため、できるだけ底面側（上記取付面側）に設けられる。そのため、図５（ｂ）に示すように、端子部１５ａと固定接点６を結ぶ導体には、上下方向に延びる接続導体垂直部位７ｃが必須となる。この接続導体垂直部７ｃを流れる電流は、アークを流れる電流と略平行且つ逆方向となるので、アークランナ９に押しだされて消弧板１３側へと駆動してきたアークを固定接点６側へと押し戻す電磁力を発生する。このアークを押し戻す電磁力を低減するために、接続導体垂直部位７ｃにはスリット８を設け、アークの走行方向から左右にずれた位置に接続導体垂直部位７ｃを配置している。さらに、略Ｌ字状の一対の磁性体板１０の第２の磁性体板の部位１０ｂの端子部１５ａ側端面が、上記左右にずれた位置に配置された接続導体垂直部位７ｃと対向するように配置されており、接続導体垂直部７ｃの電流がつくる磁界は、逆平行導体部７ｂの場合と同様に、一対の磁性体板１０と消弧板１３とで構成される磁気回路にて遮蔽されてアークには作用し難くなっているので、消弧板側へと駆動されたアークが、逆駆動方向の電磁力にて再び接点側へと押し戻されることがなく、再点弧による遮断失敗が起こり難い回路遮断器が得られる。
【００２９】
また、本実施の形態では、コアを一対の略Ｌ字状の磁性体板１０にて構成しているので、一般的な、左右の磁性体板を上部でつないだコ字状のコアに比べて、加工性、組立性に優れている。
【００３０】
実施の形態２．
図６は、この発明の実施の形態２による回路遮断器の主要部を説明するための図である。図６において、図１、及び図２と同一の符号を付したものは、同一またはこれに相当するものである。
【００３１】
図６において、１は可動接点２を有する可動接触子、５は固定接点６を有する固定接触子、１５ａは端子部、１０は前後方向に長い長方形の一対の磁性体板、１３は上記１０一対の磁性体板の上部に設けられた複数の磁性体消弧板である。同図（ａ）は、同図（ｂ）の左側面図であり、複数の消弧板の内、最下部の消弧板１３ａ以外の消弧板は省略している。上記最下部の消弧板１３ａと一対の磁性体板１０との距離ｄ２は、一対の磁性体板１０の各磁性体板間隔Ｗより小さくなるように配置されている。また、同図には本実施の形態の主要部のみ示したが、それ以外の回路遮断器を構成する部品は、基本的に実施の形態１と同様である。
【００３２】
本実施の形態では、逆平行導体部７ｂに沿って一対の磁性体板１０を設け、この一対の磁性体板と消弧板とにて磁気回路を形成して、可動接触子１を逆平行導体部７ｂを流れる電流がつくる磁界成分から遮蔽すること、閉路状態の可動接触子１に磁性体による吸引力が働き開極速度が向上すること、接続導体垂直部７ｃを流れる電流がつくるアークを接点間に押し戻す磁界成分を上記磁気回路にて遮蔽することは実施の形態１と同様である。しかし、本実施の形態では、上記磁気回路は、主に、一対の磁性体板１０と最下部消弧板１３ａにて形成されるので、最下部消弧板１３ａが磁気飽和しないように板厚を厚くする必要がある。
【００３３】
また、本実施の形態では、一対の磁性体板１０に囲まれる空間を固定接触子側に限定しているので、一対の磁性体板上部空間に容積の大きな消弧板を配置することができ、消弧板の熱容量が増加して、短絡遮断時のアークの熱による消弧板の損耗を低減できる。
【００３４】
さらに、実施の形態１で示した略Ｌ字状の一対の磁性体板に比べて、一対の磁性体板１０と開成状態の可動接触子先端部の距離を大きくできるので、磁性体板１０の絶縁が不十分で、可動接触子１、磁性体板１０、固定接触子５の経路で電流が流れて遮断不能となることを防げる。また、磁性体板形状が単純化されるので、一対の磁性体板を切り出す板材の利用率が向上する。
【００３５】
実施の形態３．
図７は、この発明の実施の形態３による回路遮断器の主要部を説明するための図である。図７において、図１、及び図２と同一の符号を付したものは、同一またはこれに相当するものである。
【００３６】
図７において、１は可動接点２を有する可動接触子、５は固定接点６を有する固定接触子、１５ａは端子部、１０は上下方向に長い長方形の一対の磁性体板、１３は上記一対の磁性体板の上部に設けられた複数の磁性体の消弧板である。同図（ａ）は、同図（ｂ）の上面図であり、消弧板１３と一対の磁性体板１０との距離ｄ３より、一対の磁性体板１０の間隔Ｗの方が大きくなるように配置されている。また、同図には本実施の形態の主要部のみ示したが、それ以外の回路遮断器を構成する部品は、基本的に実施の形態１と同様である。
【００３７】
本実施の形態では、逆平行導体部７ｂ上部に一対の磁性体板１０を設け、この一対の磁性体板と消弧板とにて磁気回路を形成して、可動接触子１を逆平行導体部７ｂを流れる電流がつくる磁界成分から遮蔽すること、閉路状態の可動接触子１に磁性体による吸引力が働き開極速度が向上すること、一対の磁性体板１０により、疑似的に馬蹄形消弧板の足の部分（消弧板切欠き部左右の部分）が可動接触子１側へと延びた構成と等価となり、アークに働く消弧板１３への吸引力が向上することは実施の形態１と同様である。しかし、本実施の形態では、接続導体垂直部７ｃと対向する位置に一対の磁性体板１０が配置されないので、接続導体垂直部７ｃを流れる電流がつくるアークを接点間に押し戻す磁界成分を一対の磁性体板１０にて遮蔽することない。代りに、この磁界成分は、一対の磁性体板１０と接続導体垂直部７ｃの間に配置される複数の磁性体消弧板１３の一部１３ｂにて、アークに対して遮蔽される。
【００３８】
また、本実施の形態では、一対の磁性体板１０に囲まれる空間を接点対側に限定しているので、アークランナ９上部に設けられる消弧板の枚数を多くすることができ、消弧板によるアーク分断、冷却作用が向上する。これにより、同作用が遮断性能に大きな影響を及ぼす過負荷以下の電流領域での遮断性能や直流遮断性能が向上するとともに、上記アーク冷却作用の向上により短絡遮断時の筐体内圧の上昇が押えられる。また、磁性体板形状が単純化されるので、一対の磁性体板を切り出す板材の利用率が向上する。
【００３９】
実施の形態４．
図８は、この発明の実施の形態４による回路遮断器の主要部を説明するための図である。図８において、図１、及び図２と同一の符号を付したものは、同一またはこれに相当するものである。
【００４０】
図８において、５は固定接点６を有する固定接触子、１５ａは端子部、１０は略Ｌ字状の一対の磁性体板（図では、手前側磁性体板を省略している）、３０は接続導体７ｃのアークランナ９側に設けられた磁性体の遮蔽板である。また、同図には本実施の形態の主要部のみ示したが、それ以外の回路遮断器を構成する部品は、基本的に実施の形態１と同様である。
【００４１】
本実施の形態では、実施の形態１とは異なり、接続導体垂直部７ｃの電流がつくるアークを接点対側へと押し戻す磁場成分を遮蔽するため、一対の磁性体板１０とは別に遮蔽板３０を設けており、これにより上記遮蔽効果をより向上させている。
【００４２】
しかし、このように遮蔽板３０をアークランナ９先端と接続導体垂直部７ｃとの間に設けると、アーク柱が伸張する空間が小さくなり、アークの伸張に起因した遮断直前の急激なアーク電圧の上昇が生じなくなる。筐体寸法等の制限から、消弧板枚数を十分設けることができない場合、このアーク伸張にともなうアーク電圧の上昇が生じないと遮断性能が著しく低下する。特に、自然に電流零点が生じない直流遮断で、その傾向が大きい。
【００４３】
実施の形態５．
図９は、この発明の実施の形態５による回路遮断器の主要部を説明するための図である。図９において、図１、及び図２と同一の符号を付したものは、同一またはこれに相当するものである。
【００４４】
図９において、５は固定接点６を有する固定接触子、１５ａは端子部、１０は略Ｌ字状の一対の磁性体板（図では、手前側磁性体板を省略している）、３１は接続導体７ｃのアークランナ９側に設けられた磁性体の一対の遮蔽板である。また、同図には本実施の形態の主要部のみ示したが、それ以外の回路遮断器を構成する部品は、基本的に実施の形態１と同様である。
【００４５】
本実施の形態では、実施の形態４で示した遮蔽板３０に相当する部品が、一対の略Ｌ字状の遮蔽板３１であり、同遮蔽板３１にて接続導体垂直部７ｃの固定接点６側の面とスリット８側の面とを覆うようにして、接続導体垂直部７ｃの電流が発生するアークを接点間に押し戻す磁界成分をアークに対して遮蔽している。さらに、遮蔽板３１は、接続導体垂直部７ｃに設けられたスリット８を塞がないので、アークが伸張する空間を確保することができ、前述の遮断性能の低下が生じることがない。
【００４６】
実施の形態６．
図１０は、この発明の実施の形態６による回路遮断器の主要部を説明するための上面図である。図１０において、図１、及び図２と同一の符号を付したものは、同一またはこれに相当するものである。
【００４７】
図１０において、５は固定接点６を有する固定接触子、９は上記固定接点から端子部１５ａ側へと延びるアークランナ、１０は絶縁カバー１２により接点対側の面を覆われた略Ｌ字状の一対の磁性体板、１３は消弧板である。また、同図には本実施の形態の主要部のみ示したが、それ以外の回路遮断器を構成する部品は、基本的に実施の形態１と同様である。
【００４８】
本実施の形態では、絶縁カバー１２の固定接点６の左右直ぐ横から可動接触子回転中心４（図示せず）側の部位に突起部１２ｄを設けて、上記突起に囲まれる空間をアークランナ９側にひらいたラッパ状となるようにしている。これにより、接点間に発生したアークは、前述の平行導体部７ａを流れる電流の磁気駆動力や磁性体の吸引力以外に、同図中に白抜き矢印で示すように、上記ラッパ状の壁面でのアークの圧力反射による力やアーク熱によるラッパ状の壁面からの蒸気流の力が、アークをアークランナ９側へと押しだすように働くので、より早い時間でアークが固定接点６を離れ、アークランナ９先端部へと移動する。これにより、固定接点６の消耗が低減するとともに、アークが消弧板１３に触れる時刻が早くなり、遮断時間が低減するので、消弧ユニットの損耗が減り、繰り返し遮断動作が行える遮断の信頼性が高い回路遮断器が得られる。
【００４９】
ところで、上記突起部１２ｄを設けると、固定接点６より可動接触子回転中心４（図示せず）側の絶縁カバー１２の内幅Ｗ'（可動接触子が移動する空間の幅）が狭くなり、可動接触子１（図示せず）の左右のブレにより、可動接触子と絶縁カバー内壁が接触して、開極速度低下による限流性能が悪化や、遮断動作時の絶縁カバー１２の沿面を介した絶縁破壊による遮断失敗の原因となることがある。そのため、可動接触子の左右のブレが大きい場合、上記ラッパ状の部位１２ｄを設けることはできない。
【００５０】
実施の形態７．
前述の実施の形態６のように絶縁カバーに突起部を設け難い場合においても、アーク熱による壁面からの蒸気によりアークを押しだす力が発生できるようにしたのが、本実施の形態である。
【００５１】
図１１は、この発明の実施の形態７による回路遮断器の主要部を説明するための上面図である。図１１において、図１０と同一の符号を付したものは、同一またはこれに相当するものである。また、同図には本実施の形態の主要部のみ示したが、それ以外の回路遮断器を構成する部品は、基本的に実施の形態１と同様である。
【００５２】
本実施の形態では、図１０の突起部１２ｄの代りに、絶縁カバーの一部１２ｅを、それ以外の絶縁カバーの部位よりアークの熱により大量の蒸気を発生する材料にて構成しており、この絶縁カバーの一部１２ｅから発生する大量の蒸気により接点間に発生したアークの前後に圧力差が生じるので、アークがアークランナ９側へと駆動される。従って、前述の電磁力によるアークを駆動する力とともに、アークの熱による絶縁カバー蒸気を利用したアークを駆動する力が得られ、且つ、前述の可動接触子１（図示せず）が絶縁カバー壁に触れることによる限流性能悪化および遮断失敗を防止できる。
【００５３】
一般に、絶縁カバー１２は成形性の良い樹脂材にてつくられる場合が多いが、この絶縁カバーには、電流遮断時にアークの圧力や高熱を受けるので、機械強度や耐熱性を上げるため、ガラス繊維やセラミック粒子などを強化材を充填する。このような強化樹脂材を絶縁カバーの主な構成材として用いた場合、絶縁カバーの一部１２ｅに非強化樹脂もしくは強化材を減らした樹脂を用いることにより、相対的に絶縁カバーの一部１２ｅの蒸気発生量をその他の部位より多くすることができる。
【００５４】
実施の形態８．
図１２は、この発明の実施の形態８による回路遮断器の主要部を説明するための部分断面図である。図１２において、図１、及び図２と同一の符号を付したものは、同一またはこれに相当するものである。
【００５５】
図１２において、３２は接続導体垂直部７ｃ（図示せず）を覆うセラミック、３３は略Ｌ字状の一対の磁性体板１０の外側の面を覆う絶縁物、３４はアークランナ９先端部より一対の磁性体板１０と消弧ユニット筐体本体２１もしくは消弧ユニット筐体蓋２２との間隙にて形成される流路である。上記絶縁物３３と絶縁カバー１２は一体に成形されており、これら絶縁物により上記一対の磁性体板１０は、固定接触子５と対向する端面を除き、全周面覆われている。同図（ａ）は、同図（ｂ）のＣ１-Ｃ１断面であり、同図（ｂ）は同図（ａ）のＣ２-Ｃ２断面であり、同図（ａ）では、可動接触子１とロータ１９を省略している。また、同図には本実施の形態の主要部のみ示したが、それ以外の回路遮断器を構成する部品は、基本的に実施の形態１と同様である。
【００５６】
前述のように、接点間に発生したアークはアークランナ９先端へと駆動され消弧板１３にて分断、冷却される。アークランナ先端部に達したアークには、接続導体垂直部７ｃを流れる電流に起因する逆駆動力（アークランナ９先端部から固定接点６側へアークを押し戻す駆動力）の他に、アークランナ先端部へアークが駆動された結果、上記接続導体垂直部７ｃを覆う絶縁物とアークが近接し、アークの熱により前記絶縁物から発生する蒸気圧によるもう一つの逆駆動力が生じる。このもう一つの逆駆動力を低減する為、本実施の形態では、接続導体垂直部７ｃを覆う絶縁物として、比較的アークの熱により蒸気を発生し難いセラミック３２を用いている。
【００５７】
また、アークの固定接点６からアークランナ９先端への走行にともない、アーク前面の気体が押されてアーク前面の圧力が高まってアーク走行速度が低下したり、アークランナ９先端に達したアークから発生する金属蒸気が接点間にもどり、接点間にて再点弧することがある。これらは、遮断時間を長くして消弧ユニットの損耗を増やすのみならず、遮断失敗の原因となることもある。そこで、本実施の形態では、走行アーク前面の圧力上昇や金属蒸気の接点間への逆流を防止するため、アークランナ先端部から一対の磁性体板１０の背面側へとつながる流路３４を設けて、図１２中の白抜き矢印で示す気流を発生させている。
【００５８】
実施の形態９．
図１３は、この発明の実施の形態９による回路遮断器の主要部を説明するための多極回路遮断器の部分断面図である。図１３において、図１、及び図２と同一の符号を付したものは、同一またはこれに相当するものである。
【００５９】
図１３において、１２ｆは回路遮断器の左右端部に配置される磁性体片１０ａもしくは１０ｆを絶縁する端極絶縁カバー、１２ｇは各極間に配置される磁性体片１０ｂ、１０ｃもしくは１０ｄ、１０ｅの対を絶縁する極間絶縁カバー、３５は各極間の可動接触子１の動きを連動させ、且つ、可動接触子回転軸４（図示せず）を介して可動接触子１の保持を行うクロスバーである。また、消弧装置を収納する消弧ユニット筐体は有しておらず、ベース２７（図示せず）とカバー２８とにて消弧装置等を直接収納している。また、磁性体の消弧板１３は省略されているが、各極において、逆平行導体部７ｂ（図示せず）に沿って一対の磁性体板を設け、この一対の磁性体板と消弧板とにて磁気回路を形成して、可動接触子１を逆平行導体部７ｂを流れる電流がつくる磁界成分から遮蔽すること、閉路状態の可動接触子１に磁性体による吸引力が働き開極速度が向上すること、接続導体垂直部７ｃ（図示せず）を流れる電流がつくるアークを接点間に押し戻す磁界成分を一対の磁性体板にて遮蔽すること等は実施の形態１と同様である。
【００６０】
本実施の形態では、各極の極間で隣り合う磁性体片１０ｂと１０ｃおよび１０ｄと１０ｅを一括して極間絶カバー１２ｇにて絶縁し、且つ、同極間絶縁カバーにて各極間の絶縁も兼ねている。また、図１３では、隣り合う磁性体片１０ｂと１０ｃおよび磁性体片１０ｄと１０ｅを各々設けたが、磁性体片１０ｂと１０ｃおよび磁性体片１０ｄと１０ｅを各々一体化してもよい。このように、各極の極間側に位置する部品を隣合う極で一体化することにより部品点数が減り、回路遮断器がより安価となる。
【００６１】
【発明の効果】
以上のように、この発明によれば、固定接点を一端部に有して閉成状態の可動接触子と略平行且つ逆方向電流が流れる平行導体部と、一端部にて上記平行導体と接続され且つ上記平行導体部の左右両側に配置されて閉成状態の上記可動接触子と略平行且つ同方向電流が流れる逆平行導体部とを有する固定接触子を用い、上記逆平行導体部の上記可動接触子側に上記可動接触子の可動接点側の一端部を左右より挟み込むように一対の磁性体板を配置し、上記一対の磁性体板を構成する各磁性体板間の間隔より、上記各磁性体板と上記可動接触子の一端部に対向して設けられた磁性体の消弧板との夫々の間隔が小さくなるようにしたしたので、上記のような回路遮断器の高さ方向の寸法を小さくできる固定接触子構成を用いた場合においても、逆平行導体部の電流がつくる磁界の影響を遮蔽することができ、短絡電流遮断時の開極速度が向上して優れた限流性能が得られ、また、アークを消弧板へと駆動する電磁力が強化されて遮断時間が短縮するので、遮断時の消弧室の損耗が低減されるものが得られる効果がある。
【００６２】
また、平行導体部の一端部にはアークランナが延設され、可動接点が固定接点から開離する方向を上方としたとき、固定接触子は、逆平行導体部の他端部から上方向に延びて端子部と接続される接続導体垂直部を有し、この接続導体垂直部には、可動接触子の開閉動作時の軌跡を含む面と交わる部位にスリットが設けられており、このスリットの左右の接続導体垂直部を構成する一対の導体部に一対の磁性体板が各々対向するようにしたので、接続導体垂直部を流れる電流によるアークを接点間に押し戻す磁界成分をアークに対して遮蔽することができ、再点弧による遮断失敗が起こり難いものが得られる効果がある。
【００６３】
さらに、平行導体部の一端部にはアークランナが延設され、可動接点が固定接点から開離する方向を上方としたとき、固定接触子は、逆平行導体部の他端部から上方向に延びて端子部と接続される接続導体垂直部を有し、この接続導体部の固定接点側の前面に磁性体の遮蔽板を配置したので、接続導体垂直部を流れる電流によるアークを接点間に押し戻す磁界成分をアークに対してより確実に遮蔽することができ、再点弧による遮断失敗が起こり難いものが得られる効果がある。
【００６４】
さらに、接続導体垂直部には、可動接触子の開閉動作時の軌跡を含む面と交わる部位にスリットが設けられており、このスリットの左右の接続導体垂直部を構成する一対の導体部の固定接点側の前面に磁性体の一対の遮蔽板を各々配置したので、接続導体垂直部を流れる電流によるアークを接点間に押し戻す磁界成分をアークに対して遮蔽し、且つ、アークランナ先端部のアークが伸張する空間を確保することができ、アーク伸張不足による遮断性能の低下が生じ難いものが得られる効果がある。
【００６５】
さらに、平行導体部の一端部にはアークランナが延設され、このアークランナの先端部は、一対の磁性体板に囲まれる空間外にあり、可動接点が固定接点から開離する方向を上方としたとき、上記アークランナの先端部の上部空間に磁性体の消弧板を配置したので、設置できる消弧板枚数を多くすることができ、消弧板によるアーク分断、冷却作用が向上し、過負荷電流遮断性能や直流遮断性能を向上させることができ、また、短絡遮断時の筐体内圧の上昇を低減できるものが得られる効果がある。
【００６６】
さらに、固定接触子は、逆平行導体部の他端部から上方向に延びて端子部と接続される接続導体垂直部を有し、複数の磁性体の消弧板の内の一部の消弧板を上記接続導体垂直部と一対の磁性体板の間に配置したので、上記接続導体垂直部を流れる電流が発生するアークを接点間に押し戻す磁界成分を上記一部の消弧板にてアークに対して遮蔽することができ、再点弧による遮断失敗の生じ難いものが得られる効果がある。
【００６７】
さらに、平行導体部の一端部にはアークランナが延設され、且つ、絶縁カバーの固定接点の直ぐ横より平行導体部の他端部側にかけての部位に突起部を設け、上記突起部に囲まれる空間が、上記アークランナ側に広がるラッパ状となるようにしたので、上記ラッパ状の絶縁物壁によるアーク圧力反射および上記絶縁壁の蒸気圧にてより早い時間でアークを固定接点からアークランナへと押しだすことができ、固定接点の消耗が低減するとともに遮断時間が短縮され、繰り返し遮断動作ができる信頼性の高いものが得られる効果がある。
【００６８】
さらに、平行導体部の一端部にはアークランナが延設され、且つ、絶縁カバーの固定接点の直ぐ横から平行導体部の他端部側にかけての部位を、その他の部位よりアークの熱により多量の蒸気を発生する物質にて形成したので、接点間に発生したアークを絶縁物蒸気に起因する圧力差による駆動力にて固定接点からアークランナに押しだすことができ、また、絶縁カバーに可動接触子が触れ難くなり、絶縁カバーの沿面を介した絶縁破壊に起因する遮断失敗が生じ難いものが得られる効果がある。
【００６９】
さらに、平行導体部の一端部にはアークランナが延設され、このアークランナ、可動接触子、固定接触子、一対の磁性体板および磁性体の消弧板が筐体にて収納され、この筐体内面と上記一対の磁性体板の反可動接触子側の面との間に、上記アークランナの先端部近傍の空間より連通する流路が形成されるようにしたので、アークランナを走行するアーク前面の圧力上昇が押えられ、アーク走行速度を向上させることができ、また、アークから発生する金属蒸気が接点間にもどることに起因する遮断失敗が生じ難いものが得られる効果がある。
【００７０】
さらに、複数の極を有し、各極ごとに一対の磁性体板を形成する磁性体片の内、極間側の磁性体片を隣り合う他極の磁性体片と一体にしたので、部品点数を減らすことができ、安価なものが得られる効果がある。
【図面の簡単な説明】
【図１】この発明の実施の形態１の回路遮断器の消弧ユニットを説明するための図である。
【図２】この発明の実施の形態１の消弧ユニット内の主要構成部品を説明するための図である。
【図３】この発明の実施の形態１の回路遮断器を説明するための図である。
【図４】この発明の実施の形態１の主要部品の位置関係と作用を説明するための図である。
【図５】この発明の実施の形態１の主要部品の位置関係と作用を説明するための図である。
【図６】この発明の実施の形態２の主要部品の位置関係と作用を説明するための図である。
【図７】この発明の実施の形態３の主要部品の位置関係と作用を説明するための図である。
【図８】この発明の実施の形態４の遮蔽板を説明するための図である。
【図９】この発明の実施の形態５の一対の遮蔽板を説明するための図である。
【図１０】この発明の実施の形態６の絶縁カバーを説明するための図である。
【図１１】この発明の実施の形態７の絶縁カバーを説明するための図である。
【図１２】この発明の実施の形態８の消弧ユニット内部構成を説明するための図である。
【図１３】この発明の実施の形態９の多極回路遮断器を説明するための図である。
【図１４】従来の回路遮断器を説明するための図である。
【図１５】従来の別の回路遮断器の固定接触子構造を説明するための図である。
【符号の説明】
１可動接触子、２可動接点、５固定接触子、６固定接点、７ａ平行導体部、７ｂ逆平行導体部、７ｃ接続導体垂直部、８スリット、９アークランナ、１０一対の磁性体板、１０ａ、１０ｂ、１０ｃ、１０ｄ、１０ｅ、１０ｆ磁性体片、１２絶縁カバー、１２ｄ突起部、１２ｅ絶縁カバーの一部、１３消弧板、１３ｂ一部の消弧板、１５ａ端子部、２１、２２筐体、２５機構部、３０遮蔽板、３１一対の遮蔽板、３４流路[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a circuit breaker that opens a contact using electromagnetic force generated between parallel conductors by a short-circuit current.
[0002]
[Prior art]
FIG. 14 is a partial sectional view showing a conventional circuit breaker disclosed in, for example, Japanese Patent Publication No. 62-2423. In the figure, 1 is a movable contact with a movable contact 2 fixed to one end, and 5 is a movable contact. 2 is a fixed contact having a fixed contact 6 that forms a contact pair, and is connected to a power supply circuit at a terminal portion 15a. In the closed state, the movable contact 1 and the fixed contact 5 are superposed at a slight distance in the vertical direction and are held parallel to each other. Reference numeral 13 denotes a plurality of arc extinguishing plates held by the arc extinguishing side plate 14, 25 denotes a mechanism portion that opens and closes the movable contact 1, and 29 denotes a handle for manually operating the mechanism portion 25. These components are housed in a housing composed of a cover 28 and a base 27.
[0003]
Next, the operation will be described. In the opening and closing at the time of normal energization, the mechanism unit 25 is operated by the operation of the handle 29, and the movable contact 1 is rotated and opened and closed. On the other hand, when a large current such as a short-circuit current flows in the closed circuit state, the contact is released regardless of the mechanism section due to the electromagnetic repulsive force due to the reverse current flowing in the movable contact and the stationary contact. In response, the mechanism unit 25 is driven to a shut-off state by the operation of a tripping mechanism (not shown). Accordingly, an arc can be generated between the contacts 2 and 6 at an early stage immediately after the occurrence of the accident, and this arc can be extended rapidly, and the arc voltage between the contacts quickly rises. The arc current limits the fault current. Subsequently, when the instantaneous current value decreases, the arc is drawn into the iron arc extinguishing plate 13 and is cut off, cooled, and extinguished, so that the current is interrupted.
[0004]
In such a circuit breaker shown in FIG. 14, the stationary contact 5 is bent in a substantially U shape so as to secure a parallel conductor portion 7 a that faces the movable contact 1 in a closed state and flows a parallel and reverse current. The fixed contact 6 is fixed to the tip portion facing the movable contact. In such a stationary contact, in order to reduce the influence of the current flowing through the antiparallel conductor portion 7b that generates an electromagnetic attractive force in the movable contact 1, and the vertical conductor portion 7e due to the restriction of the mold at the time of bending. The height of the circuit breaker cannot be reduced, making it difficult to reduce the size of the circuit breaker in the height direction, and further, the conductor of the fixed contactor becomes longer and the cost of parts increases.
[0005]
Therefore, in another conventional circuit breaker disclosed in the above publication, the circuit breaker is miniaturized in the height direction with the fixed contactor structure shown in FIG. In FIG. 15, the stationary contact 5 has a U-shaped through hole 36 at a portion facing the movable contact 1 (not shown) so as to form a tongue piece extending from the distal end side 5b toward the proximal end side 5a. Is provided. The tongue piece is formed by a parallel conductor portion 7a through which a reverse current flows in parallel with the movable contact in the closed state and a fixed contact 6 fixed to one end thereof, and is parallel to the movable contact in the closed state and The antiparallel conductor portion 7b through which the current in the same direction flows is arranged at the same height as the parallel conductor portion 7a, and there is no conductor extending in the vertical direction like the vertical conductor portion 7e in FIG. Therefore, the dimension of the circuit breaker in the height direction can be reduced, and user convenience is improved. Moreover, it is not necessary to use a bending process for manufacturing the stationary contact, and the workability is improved.
[0006]
[Problems to be solved by the invention]
In a conventional circuit breaker, a parallel conductor portion that generates an electromagnetic repulsive force in parallel with a closed movable contact and an electric circuit that forms other stationary contacts are arranged at the same height. However, the height dimension can be reduced, but there is an anti-parallel conductor part that generates an electromagnetic attractive force to the movable contact by flowing in the same direction and in the same direction as the closed movable contact. Therefore, the opening speed of the movable contact at the time of a short circuit accident cannot be sufficiently increased. In particular, when there is a limit on the width of the circuit breaker (the direction perpendicular to the direction in which the movable contact extends), the antiparallel conductor part is arranged at the same height as the parallel conductor part. The force for electromagnetically attracting the movable contact generated by the current flowing through the coil may be larger than when the substantially U-shaped fixed contact shown in FIG. 14 is used, and the opening speed of the movable contact decreases. Therefore, there was a problem that sufficient current limiting performance could not be obtained.
[0007]
The magnetic field component generated by the current flowing in the antiparallel conductor part cancels the magnetic field component that extends the arc generated by the current flowing in the parallel conductor part to the arc extinguishing plate, and the arc generated between the contacts is It becomes difficult to be divided and cooled. As a result, there is a problem that the interruption time becomes longer and wear of the arc extinguishing chamber components increases or, in the worst case, the interruption becomes impossible.
[0008]
The present invention has been made to solve the above-described problems, and it is possible to obtain a circuit breaker having excellent current-limiting performance even in a circuit breaker having a reduced size in the height direction of the circuit breaker. It is intended.
[0009]
[Means for Solving the Problems]
In the circuit breaker according to the present invention, the fixed contact has a fixed contact at one end, a parallel conductor portion that is substantially parallel to the closed movable contact and through which a reverse current flows, and the above-mentioned at one end. An antiparallel conductor portion connected to the parallel conductor and disposed on both left and right sides of the parallel conductor portion and the movable contactor in a closed state and an approximately parallel and unidirectional current flow. A pair of magnetic plates is arranged on the movable contact side so as to sandwich one end portion of the movable contact side of the movable contact from the left and right, and from the interval between the magnetic plates constituting the pair of magnetic plates, The intervals between the magnetic plates and the magnetic arc-extinguishing plates provided to face one end of the movable contact are reduced.
[0010]
In addition, an arc runner is provided at one end of the parallel conductor, and the fixed contact extends upward from the other end of the antiparallel conductor when the direction in which the movable contact is separated from the fixed contact is upward. The connecting conductor vertical portion is connected to the terminal portion, and the connecting conductor vertical portion is provided with a slit at a portion that intersects the surface including the locus during the opening / closing operation of the movable contact. A pair of magnetic plates are respectively opposed to a pair of conductor portions constituting the connecting conductor vertical portion.
[0011]
In addition, an arc runner is provided at one end of the parallel conductor, and the fixed contact extends upward from the other end of the antiparallel conductor when the direction in which the movable contact is separated from the fixed contact is upward. The connecting conductor vertical portion is connected to the terminal portion, and a magnetic shielding plate is disposed on the front surface of the connecting conductor portion on the fixed contact side.
[0012]
The connecting conductor vertical part is provided with a slit at a portion intersecting with the surface including the locus during the opening / closing operation of the movable contact, and the pair of conductor parts constituting the right and left connecting conductor vertical parts of the slit are fixed. A pair of shielding plates made of a magnetic material are respectively arranged on the front surface on the contact side.
[0013]
In addition, an arc runner is extended at one end of the parallel conductor, and the tip of the arc runner is outside the space surrounded by the pair of magnetic plates, and the direction in which the movable contact is separated from the fixed contact is upward. At this time, an arc extinguishing plate made of a magnetic material is disposed in the upper space at the tip of the arc runner.
[0014]
The fixed contact has a connecting conductor vertical portion extending upward from the other end of the antiparallel conductor portion and connected to the terminal portion, and a part of the plurality of magnetic arc extinguishing plates is extinguished. An arc plate is disposed between the connecting conductor vertical portion and the pair of magnetic plates.
[0015]
In addition, an arc runner is provided at one end of the parallel conductor portion, and a protrusion is provided at a portion from the side next to the fixed contact of the insulating cover to the other end of the parallel conductor portion, and is surrounded by the protrusion. The space is formed in a trumpet shape extending toward the arc runner side.
[0016]
In addition, an arc runner is extended at one end of the parallel conductor portion, and a part from the side next to the fixed contact of the insulating cover to the other end side of the parallel conductor part is larger than the other part by the heat of the arc. It is made of a material that generates steam.
[0017]
An arc runner extends from one end of the parallel conductor, and the arc runner, the movable contact, the fixed contact, the pair of magnetic plates, and the magnetic arc extinguishing plate are housed in a housing. A flow path communicating from the space near the tip of the arc runner is formed between the surface and the surface of the pair of magnetic plates on the side opposite to the movable contact.
[0018]
In addition, among magnetic pieces having a plurality of poles and forming a pair of magnetic plates for each pole, the magnetic pieces on the interpolar side are integrated with adjacent magnetic pieces. .
[0019]
DETAILED DESCRIPTION OF THE INVENTION
Embodiment 1 FIG.
FIG. 1 is a diagram for explaining a circuit breaker according to Embodiment 1 of the present invention, and more specifically, a partial cross-sectional perspective view of an arc extinguishing unit portion in an open state. FIG. 2 is an exploded view of the main part disposed in the arc extinguishing unit. FIG. 3 is a development view showing the configuration of a circuit breaker configured using the arc extinguishing unit shown in FIG.
[0020]
In FIG. 1, reference numeral 1 denotes a movable contact having a movable contact 2 (not shown) fixed to one end thereof, and 5 denotes a fixed contact that forms a contact pair with the movable contact 1. Reference numeral 10 denotes a pair of substantially L-shaped magnetic plates, which are arranged so as to sandwich the movable contact 1 from the left and right sides, and the surface on the movable contact 1 side is covered with an insulating cover 12. Reference numeral 13 denotes a plurality of horseshoe-shaped arc extinguishing plates made of a magnetic material held by the arc extinguishing side plate 14. Reference numeral 17 denotes a spring that generates a contact pressure on the movable contact 1, and one end thereof is held by a spring hook 18. 16 is a sliding contact for electrically connecting the terminal portion 15c and the movable contact 1, and 19 is a movement of the mechanism 25 (not shown) to the movable contact 1 via a crossbar 24 (not shown). It is a transmitting rotor and has a cross section so that the internal structure of this rotor can be seen. The parts forming these arc-extinguishing units are housed in the arc-extinguishing unit casing body 21 and the arc-extinguishing unit casing lid 22.
[0021]
In FIG. 2, the main component configuration inside the arc-extinguishing unit will be described in more detail. The fixed contact 5 has a tongue piece to which the fixed contact 6 is fixed, and this tongue piece is a movable contact in a closed state. A parallel conductor portion 7a through which a current substantially parallel to and opposite to the child 1 flows and an arc runner 9 extending from the fixed contact 6 to the opposite rotor 19 side are provided. The parallel conductor portion 7a is connected to one end of the antiparallel conductor portion 7b on the rotor 19 side, and the antiparallel conductor portion 7b is disposed at substantially the same height on the left and right of the parallel conductor portion 7a. The other end is connected to the terminal portion 15a via a connecting conductor vertical portion 7c extending in the vertical direction and a connecting conductor parallel portion 7d extending in the front-rear direction. The connecting conductor vertical portion 7c and the connecting conductor parallel portion 7d are provided with slits 8 along the plane including the trajectory of the rotation of the movable contact 1. A pair of magnetic plates 10 in a state of being electrically insulated from the fixed contact by the insulating sheet 11 is provided at the upper part of the antiparallel conductor portion 7b of the fixed contact 5 so that the end of the movable contact 1 on the side of the movable contact 2 is disposed. The insulating cover 12 covers the inner surface, the rotor-side end surface, and the arc-extinguishing plate 13-side end surface of the pair of magnetic plates 10 that are arranged so as to be sandwiched and exposed to the arc generated between the contacts.
[0022]
The pair of magnetic plates extend along the portion 10a of the first magnetic plate extending in the vertical direction on the left and right of the movable contact 1 and the antiparallel conductor portion 7b, and one end faces the connecting conductor vertical portion 7c. Each of the second magnetic plate portions 10b is substantially L-shaped. The insulating cover 12 includes a first insulating cover portion 12a that covers the pair of magnetic plates, a second insulating cover portion 12b that covers the top surface of the parallel conductor portion 7a, and a first cover that covers the connection conductors 7c and 7d. 3 of the insulating cover 3 is integrally formed. A plurality of magnetic material arc extinguishing plates 13 held by the arc extinguishing side plate 14 are disposed on the insulating cover. The arc extinguishing plate has a horseshoe shape having a notch on the movable contact 1 side. In addition, the movable contact 1 is rotatably held by the mover rotating shaft 4 and is configured to transmit the movement of the mechanism portion 25 (not shown) via the rotor 19. The rotor 19 is provided with a through hole for communicating a crossbar 24 (not shown). As shown in FIG. 3, a plurality of such arc-extinguishing chamber units 23 are communicated with each other by crossbars 24, the crossbars are engaged with the mechanism portions 25, and abnormalities in the circuits are detected by detecting the above-described abnormalities. If the relay unit 26 and the handle 29 that drive the mechanism unit are housed in a housing made up of the cover 28 and the base 27, a circuit breaker is configured.
[0023]
Next, the operation will be described. In the opening and closing at the time of normal energization, the mechanism unit 25 is operated by the operation of the handle 29, and the movable contact 1 is rotated and opened and closed. On the other hand, when a large current such as a short-circuit current flows in the closed circuit state, the contact is released regardless of the mechanism section due to the electromagnetic repulsive force due to the reverse current flowing in the movable contact and the stationary contact. In response, the operation of the relay unit 26 drives the mechanism unit 25 to the cut-off state. Accordingly, an arc can be generated between the contacts 2 and 6 at an early stage immediately after the occurrence of the accident, and this arc can be extended rapidly, and the arc voltage between the contacts quickly rises. The arc current limits the fault current. Subsequently, when the instantaneous current value decreases, the arc is drawn into the iron arc extinguishing plate 13 and is cut off, cooled, and extinguished, so that the current is interrupted. These breaking operations are basically the same as those of the conventional circuit breaker. Further, the parallel conductor portion 7a that is parallel to the closed state movable contact and flows in the reverse direction, and the antiparallel conductor portion 7b that is parallel to the closed state movable contact and flows in the same direction have the same height as the electric circuit 7a. By arranging the circuit breaker, the dimension in the height direction of the circuit breaker can be reduced, the convenience of the user is improved, and it is not necessary to use a bending process for manufacturing the stationary contact, and the workability is also improved. Similar to another conventional circuit breaker.
[0024]
However, in the present embodiment, unlike the other conventional circuit breaker described above, a pair of substantially L-shaped magnetic plates 10 are arranged on the upper part of the antiparallel conductor portion 7b, and the pair of magnetic plates and the magnetic A magnetic circuit is formed by the body arc extinguishing plate 13, and the magnetic field component generated by the current of the antiparallel conductor portion 7b is prevented from acting on the arc generated between the movable contact 1 and the contact, and the movable contact described above. And driving the arc.
[0025]
4 and 5 are explanatory views schematically showing the positional relationship among the movable contact 1, the fixed contact 5, the pair of magnetic plates 10 and the arc extinguishing plate 13 in the present embodiment. FIG. 4 shows a closed state, and FIG. 5 shows a state where the movable contact during the breaking operation is fully opened. Fig.5 (a) is the figure which looked at FIG.5 (b) from the upper direction. In FIGS. 4 and 5 (b), the flow of current is indicated by white arrows. As shown in FIG. 5A, the interval W between the pair of magnetic plates 10 provided on the upper portion of the antiparallel conductor portion 7b is larger than the gap d1 between the pair of magnetic plates 10 and the arc extinguishing plate 13. Has been.
[0026]
With such a configuration, in the closed state shown in FIG. 4, the magnetic flux generated by the current flowing through the antiparallel conductor portion 7 b (the magnetic field component that prevents the opening of the movable contact 1) is generated by the pair of magnetic plates 10 and Since the arc-extinguishing plate 13 passes through the magnetic circuit, it does not act on the movable contact 1 (the movable contact 1 is shielded from a magnetic field component generated by the current flowing through the antiparallel conductor portion 7b). Furthermore, since the movable contact 1 in the closed state is located in a space surrounded by a substantially U-shaped magnetic body formed by the pair of magnetic plates 10 and the arc extinguishing plate 13, the above-described magnetic body is used. The attractive force works and the opening speed is improved (in other words, the current limiting performance is improved).
[0027]
Similarly, as shown in FIG. 5B, the magnetic field generated by the current flowing through the antiparallel conductor portion 7b does not act on the arc generated between the contacts, and the arc generates a magnetic field generated by the current of the parallel conductor portion 7a. Is pushed out to the arc runner 9. Furthermore, the arc is located in a space surrounded by a substantially U-shaped magnetic body formed by the pair of magnetic body plates 10 and the arc-extinguishing plate 13, and is a part of the foot of the horseshoe-shaped arc-extinguishing plate in a pseudo manner Since (the left and right portions of the cutout portion of the arc extinguishing plate) is equivalent to a configuration extending to the movable contact 1 side, the attractive force to the arc extinguishing plate 13 acting on the arc is improved. By improving the suction force, the time when the arc is divided and cooled by the arc extinguishing plate is advanced, so that the interruption time can be shortened and the arc extinguishing chamber is reduced in wear. Moreover, it becomes possible to prevent the hot gas from filling up and becoming impossible to shut off due to the long arc time.
[0028]
By the way, the terminal part of the circuit breaker is generally provided at a position higher than the mounting surface because of the connection screw and the like with the electric wire. On the other hand, the fixed contact 6 is provided on the bottom surface side (the mounting surface side) as much as possible in order to reduce the height direction of the circuit breaker by making maximum use of the internal space of the housing. For this reason, as shown in FIG. 5B, the conductor connecting the terminal portion 15a and the fixed contact 6 must have a connecting conductor vertical portion 7c extending in the vertical direction. Since the current flowing through the connecting conductor vertical portion 7c is substantially parallel to and opposite to the current flowing through the arc, the arc driven by the arc runner 9 and driven toward the arc extinguishing plate 13 is moved to the fixed contact 6 side. Generates electromagnetic force to push back. In order to reduce the electromagnetic force that pushes back the arc, a slit 8 is provided in the connecting conductor vertical portion 7c, and the connecting conductor vertical portion 7c is arranged at a position shifted left and right from the traveling direction of the arc. Further, the terminal part 15a side end surface of the portion 10b of the second magnetic plate of the pair of substantially L-shaped magnetic plates 10 faces the connecting conductor vertical portion 7c arranged at the position shifted to the left and right. The magnetic field generated by the current of the connecting conductor vertical portion 7c is shielded by a magnetic circuit composed of the pair of magnetic plates 10 and the arc extinguishing plate 13 as in the case of the antiparallel conductor portion 7b. Since it is difficult to act on the arc, the arc driven to the arc extinguishing plate side is not pushed back to the contact side again by the electromagnetic force in the reverse drive direction, and the interruption failure due to re-ignition A circuit breaker that is less likely to occur is obtained.
[0029]
In the present embodiment, the core is composed of a pair of substantially L-shaped magnetic plates 10, so that it is compared with a general U-shaped core in which left and right magnetic plates are connected at the top. Excellent workability and assembly.
[0030]
Embodiment 2. FIG.
FIG. 6 is a diagram for explaining a main part of a circuit breaker according to Embodiment 2 of the present invention. In FIG. 6, the same reference numerals as those in FIGS. 1 and 2 are the same or equivalent.
[0031]
In FIG. 6, 1 is a movable contact having a movable contact 2, 5 is a fixed contact having a fixed contact 6, 15 a is a terminal portion, 10 is a pair of rectangular magnetic plates that are long in the front-rear direction, and 13 is the above-mentioned 10 pairs. A plurality of magnetic material arc extinguishing plates provided on an upper portion of the magnetic material plate. The figure (a) is the left view of the figure (b), and arc-extinguishing plates other than the lowest arc-extinguishing board 13a are abbreviate | omitted among several arc-extinguishing boards. A distance d2 between the lowermost arc extinguishing plate 13a and the pair of magnetic plates 10 is arranged to be smaller than the interval W between the magnetic plates of the pair of magnetic plates 10. Moreover, although only the principal part of this Embodiment was shown in the figure, the components which comprise the circuit breaker other than that are the same as that of Embodiment 1 fundamentally.
[0032]
In the present embodiment, a pair of magnetic plates 10 is provided along the antiparallel conductor portion 7b, and a magnetic circuit is formed by the pair of magnetic plates and the arc extinguishing plate, so that the movable contact 1 is antiparallel. Shielding from the magnetic field component generated by the current flowing through the conductor portion 7b, the attraction force by the magnetic body acting on the closed movable contact 1 to improve the opening speed, and the arc generated by the current flowing through the connecting conductor vertical portion 7c The magnetic field component pushed back between the contacts is shielded by the magnetic circuit as in the first embodiment. However, in the present embodiment, the magnetic circuit is mainly formed by a pair of magnetic plates 10 and the lowermost arc extinguishing plate 13a, so that the lower arc extinguishing plate 13a is not magnetically saturated. It is necessary to thicken.
[0033]
In the present embodiment, since the space surrounded by the pair of magnetic plates 10 is limited to the fixed contact side, a large volume arc extinguishing plate can be disposed in the upper space of the pair of magnetic plates. The heat capacity of the arc extinguishing plate is increased, and the wear of the arc extinguishing plate due to the heat of the arc when the short circuit is interrupted can be reduced.
[0034]
Furthermore, since the distance between the pair of magnetic plates 10 and the open movable contact tip can be increased compared to the pair of substantially L-shaped magnetic plates shown in the first embodiment, the magnetic plate 10 Insulation is insufficient, and it is possible to prevent a current from flowing through the path of the movable contact 1, the magnetic plate 10, and the fixed contact 5, thereby making it impossible to cut off. Further, since the magnetic plate shape is simplified, the utilization factor of the plate material for cutting out the pair of magnetic plates is improved.
[0035]
Embodiment 3 FIG.
FIG. 7 is a diagram for explaining a main part of a circuit breaker according to Embodiment 3 of the present invention. In FIG. 7, the same reference numerals as those in FIGS. 1 and 2 are the same or equivalent.
[0036]
In FIG. 7, 1 is a movable contact having a movable contact 2, 5 is a fixed contact having a fixed contact 6, 15 a is a terminal portion, 10 is a pair of long magnetic plates in the vertical direction, and 13 is a pair of the above-described pairs. A plurality of magnetic arc-extinguishing plates provided on an upper portion of the magnetic plate. FIG. 4A is a top view of FIG. 4B, and the distance W between the pair of magnetic plates 10 is larger than the distance d3 between the arc extinguishing plate 13 and the pair of magnetic plates 10. Is arranged. Moreover, although only the principal part of this Embodiment was shown in the figure, the components which comprise the circuit breaker other than that are the same as that of Embodiment 1 fundamentally.
[0037]
In the present embodiment, a pair of magnetic plates 10 is provided on the antiparallel conductor portion 7b, and a magnetic circuit is formed by the pair of magnetic plates and the arc extinguishing plate. Shielding from the magnetic field component generated by the current flowing through the portion 7b, the attractive force by the magnetic material acting on the closed movable contact 1 and improving the opening speed, and a pair of magnetic plates 10 in a pseudo horseshoe shape It is equivalent to the configuration in which the foot portions of the arc plate (the left and right portions of the arc extinguishing plate notch portion) extend to the movable contact 1 side, and the attraction force to the arc extinguishing plate 13 acting on the arc is improved. This is the same as the first embodiment. However, in the present embodiment, since the pair of magnetic plates 10 is not disposed at a position facing the connection conductor vertical portion 7c, a pair of magnetic field components that push back the arc generated by the current flowing through the connection conductor vertical portion 7c between the contact points. It is not shielded by the magnetic plate 10. Instead, the magnetic field component is shielded against the arc by the portions 13b of the plurality of magnetic material arc extinguishing plates 13 disposed between the pair of magnetic material plates 10 and the connecting conductor vertical portion 7c.
[0038]
In the present embodiment, the space surrounded by the pair of magnetic plates 10 is limited to the contact pair side, so that the number of arc extinguishing plates provided on the arc runner 9 can be increased, and the arc extinguishing plates can be increased. This improves arc cutting and cooling effect. As a result, the interruption performance in the current region below the overload and the DC interruption performance that have the same effect on the interruption performance are improved, and the increase in the internal pressure at the time of short-circuit interruption is suppressed by improving the arc cooling action. It is done. Further, since the magnetic plate shape is simplified, the utilization factor of the plate material for cutting out the pair of magnetic plates is improved.
[0039]
Embodiment 4 FIG.
FIG. 8 is a diagram for explaining a main part of a circuit breaker according to Embodiment 4 of the present invention. In FIG. 8, the same reference numerals as those in FIGS. 1 and 2 are the same or equivalent.
[0040]
In FIG. 8, 5 is a fixed contact having a fixed contact 6, 15a is a terminal portion, 10 is a pair of substantially L-shaped magnetic plates (in the figure, the front side magnetic plate is omitted), 30 It is a magnetic shielding plate provided on the arc runner 9 side of the connecting conductor 7c. Moreover, although only the principal part of this Embodiment was shown in the figure, the components which comprise the circuit breaker other than that are the same as that of Embodiment 1 fundamentally.
[0041]
In the present embodiment, unlike the first embodiment, the shielding plate 30 is separated from the pair of magnetic plates 10 in order to shield the magnetic field component that pushes back the arc generated by the current in the connecting conductor vertical portion 7c to the contact pair side. As a result, the shielding effect is further improved.
[0042]
However, when the shielding plate 30 is provided between the tip of the arc runner 9 and the connecting conductor vertical portion 7c in this way, the space in which the arc column extends is reduced, and a sudden increase in arc voltage immediately before the interruption due to the arc extension occurs. Will not occur. If a sufficient number of arc extinguishing plates cannot be provided due to restrictions on the size of the casing, etc., the interruption performance will be significantly reduced unless the arc voltage increases due to this arc extension. In particular, the tendency is large in direct current interruption where a current zero point does not occur naturally.
[0043]
Embodiment 5 FIG.
FIG. 9 is a diagram for explaining a main part of a circuit breaker according to Embodiment 5 of the present invention. 9, the same reference numerals as those in FIGS. 1 and 2 denote the same or corresponding parts.
[0044]
In FIG. 9, 5 is a fixed contact having a fixed contact 6, 15a is a terminal part, 10 is a pair of substantially L-shaped magnetic plates (in the figure, the front magnetic plate is omitted), 31 These are a pair of magnetic shielding plates provided on the arc runner 9 side of the connection conductor 7c. Moreover, although only the principal part of this Embodiment was shown in the figure, the components which comprise the circuit breaker other than that are the same as that of Embodiment 1 fundamentally.
[0045]
In the present embodiment, the parts corresponding to the shielding plate 30 shown in the fourth embodiment are a pair of substantially L-shaped shielding plates 31, and the fixed contact 6 of the connecting conductor vertical portion 7 c by the shielding plate 31. The magnetic field component that pushes back the arc generated by the current of the connecting conductor vertical portion 7c between the contacts is shielded against the arc so as to cover the surface on the side and the surface on the slit 8 side. Furthermore, since the shielding plate 31 does not block the slit 8 provided in the connecting conductor vertical portion 7c, a space in which the arc extends can be secured, and the above-described degradation of the shielding performance does not occur.
[0046]
Embodiment 6 FIG.
FIG. 10 is a top view for explaining a main part of a circuit breaker according to Embodiment 6 of the present invention. In FIG. 10, the same reference numerals as those in FIGS. 1 and 2 are the same or equivalent.
[0047]
In FIG. 10, 5 is a stationary contact having a stationary contact 6, 9 is an arc runner extending from the stationary contact to the terminal portion 15 a side, and 10 is a substantially L-shaped surface covered with an insulating cover 12. A pair of magnetic plates 13 are arc extinguishing plates. Moreover, although only the principal part of this Embodiment was shown in the figure, the components which comprise the circuit breaker other than that are the same as that of Embodiment 1 fundamentally.
[0048]
In the present embodiment, a protrusion 12d is provided at a position on the movable contact rotating center 4 (not shown) side from the right and left of the fixed contact 6 of the insulating cover 12, and the space surrounded by the protrusion is formed on the arc runner 9 side. A trumpet shape is opened. As a result, the arc generated between the contacts is not only the magnetic driving force of the current flowing through the parallel conductor portion 7a and the attractive force of the magnetic material, but also the trumpet-shaped wall surface as indicated by the white arrow in the figure. The force of the steam reflected from the arc and the force of the steam flow from the trumpet-shaped wall surface due to the arc heat acts to push the arc toward the arc runner 9 side, so that the arc leaves the fixed contact 6 in an earlier time, Move to the tip of the arcrunner 9. As a result, the wear of the fixed contact 6 is reduced, the time when the arc touches the arc extinguishing plate 13 is shortened, and the interruption time is reduced, so that the wear of the arc extinguishing unit is reduced and the interruption reliability can be repeated. A high circuit breaker is obtained.
[0049]
By the way, when the protrusion 12d is provided, the inner width W ′ (the width of the space in which the movable contact moves) of the insulating cover 12 on the movable contact rotating center 4 (not shown) side from the fixed contact 6 becomes narrower. The movable contact 1 (not shown) has left and right movements that cause contact between the movable contact and the inner wall of the insulating cover, thereby deteriorating the current limiting performance due to a decrease in the opening speed, and via the creeping surface of the insulating cover 12 during the breaking operation. May cause failure due to insulation breakdown. For this reason, the trumpet-shaped portion 12d cannot be provided when the left and right blurs of the movable contactor are large.
[0050]
Embodiment 7 FIG.
In the present embodiment, even when it is difficult to provide a protrusion on the insulating cover as in the sixth embodiment described above, the force that pushes the arc by the steam from the wall surface caused by the arc heat can be generated.
[0051]
FIG. 11 is a top view for explaining a main part of a circuit breaker according to Embodiment 7 of the present invention. In FIG. 11, the same reference numerals as those in FIG. 10 denote the same or corresponding parts. Moreover, although only the principal part of this Embodiment was shown in the figure, the components which comprise the circuit breaker other than that are the same as that of Embodiment 1 fundamentally.
[0052]
In the present embodiment, instead of the protrusion 12d in FIG. 10, a part 12e of the insulating cover is made of a material that generates a large amount of vapor by the heat of the arc from the other part of the insulating cover, Since a large amount of steam generated from the part 12e of the insulating cover causes a pressure difference before and after the arc generated between the contacts, the arc is driven toward the arc runner 9 side. Therefore, in addition to the force for driving the arc by the electromagnetic force described above, the force for driving the arc using the insulating cover steam by the heat of the arc is obtained, and the above-mentioned movable contact 1 (not shown) is provided on the insulating cover wall. It is possible to prevent current-limiting performance deterioration and interruption failure due to touching.
[0053]
In general, the insulating cover 12 is often made of a resin material having good moldability. However, since this insulating cover is subjected to arc pressure and high heat when the current is interrupted, glass fiber is used to increase mechanical strength and heat resistance. Fill with reinforcing material such as ceramic particles. When such a reinforced resin material is used as a main constituent material of the insulating cover, the insulating cover part 12e can be relatively made by using a non-reinforced resin or a resin with a reduced reinforcing material for the insulating cover part 12e. It is possible to increase the amount of steam generated from other parts.
[0054]
Embodiment 8 FIG.
FIG. 12 is a partial cross-sectional view for explaining a main part of a circuit breaker according to Embodiment 8 of the present invention. In FIG. 12, the same reference numerals as those in FIGS. 1 and 2 are the same or equivalent.
[0055]
In FIG. 12, 32 is a ceramic covering the connection conductor vertical portion 7c (not shown), 33 is an insulator covering the outer surface of the pair of substantially L-shaped magnetic plates 10, and 34 is a pair from the tip of the arc runner 9. The magnetic material plate 10 and the arc extinguishing unit housing main body 21 or the arc extinguishing unit housing lid 22 form a flow path. The insulator 33 and the insulating cover 12 are integrally formed, and the pair of magnetic plates 10 are covered with these insulators except for the end face facing the fixed contact 5. 2A is a cross section taken along line C1-C1 in FIG. 1B. FIG. 1B is a cross section taken along line C2-C2 in FIG. 1A. In FIG. And the rotor 19 is omitted. Moreover, although only the principal part of this Embodiment was shown in the figure, the components which comprise the circuit breaker other than that are the same as that of Embodiment 1 fundamentally.
[0056]
As described above, the arc generated between the contacts is driven to the tip of the arc runner 9 and is divided and cooled by the arc extinguishing plate 13. In addition to the reverse driving force (driving force that pushes the arc back from the arc runner 9 tip to the fixed contact 6 side) caused by the current flowing through the connecting conductor vertical portion 7c, the arc that reaches the arc runner tip is arced to the arc runner tip. As a result, the insulator covering the connecting conductor vertical portion 7c and the arc are close to each other, and another reverse driving force is generated by the vapor pressure generated from the insulator due to the heat of the arc. In order to reduce this other reverse driving force, in the present embodiment, ceramic 32 that does not easily generate steam due to the heat of arc is used as an insulator covering the connecting conductor vertical portion 7c.
[0057]
Further, as the arc travels from the stationary contact 6 to the tip of the arc runner 9, the gas on the front side of the arc is pushed to increase the pressure on the front side of the arc and the arc traveling speed decreases, or the arc travels from the arc reaching the tip of the arc runner 9. Metal vapor may return between the contacts and reignite between the contacts. These not only increase the wear time of the arc-extinguishing unit by extending the cut-off time, but may cause a cut-off failure. Therefore, in the present embodiment, in order to prevent a pressure increase on the front surface of the traveling arc and a back flow between the contact points of the metal vapor, a flow path 34 connected from the arc runner tip to the back side of the pair of magnetic plates 10 is provided. The airflow shown by the white arrow in FIG. 12 is generated.
[0058]
Embodiment 9 FIG.
FIG. 13 is a partial cross-sectional view of a multipolar circuit breaker for explaining the main part of a circuit breaker according to Embodiment 9 of the present invention. In FIG. 13, the same reference numerals as those in FIGS. 1 and 2 are the same or equivalent.
[0059]
In FIG. 13, 12f is an end electrode insulating cover for insulating the magnetic piece 10a or 10f arranged at the left and right ends of the circuit breaker, and 12g is a magnetic piece 10b, 10c or 10d, 10e arranged between the poles. The inter-electrode insulating cover 35 that insulates the pair of the electrodes interlocks the movement of the movable contact 1 between the respective poles, and holds the movable contact 1 via the movable contact rotating shaft 4 (not shown). It is a crossbar. Further, the arc extinguishing unit housing for accommodating the arc extinguishing device is not provided, and the arc extinguishing device or the like is directly accommodated by the base 27 (not shown) and the cover 28. Further, although the magnetic arc extinguishing plate 13 is omitted, a pair of magnetic plates are provided along the antiparallel conductor portion 7b (not shown) at each pole, and the pair of magnetic extinguishing plates and arc extinguishing are provided. A magnetic circuit is formed with the plate to shield the movable contact 1 from a magnetic field component generated by the current flowing through the antiparallel conductor portion 7b, and the magnetic contact force acts on the closed movable contact 1 to open the pole. As in the first embodiment, the speed is improved and the magnetic field component that pushes back the arc generated by the current flowing through the connecting conductor vertical portion 7c (not shown) between the contacts is shielded by a pair of magnetic plates. .
[0060]
In the present embodiment, the adjacent magnetic pieces 10b and 10c and 10d and 10e between the poles of each pole are collectively insulated by the gap-break cover 12g, and each pole is separated by the same-pole insulation cover. Also serves as an insulation. In FIG. 13, the adjacent magnetic pieces 10b and 10c and the magnetic pieces 10d and 10e are provided, but the magnetic pieces 10b and 10c and the magnetic pieces 10d and 10e may be integrated. In this way, by integrating the parts located between the poles with the adjacent poles, the number of parts is reduced, and the circuit breaker becomes cheaper.
[0061]
【The invention's effect】
As described above, according to the present invention, a parallel conductor portion having a fixed contact at one end and substantially parallel to the closed movable contact and through which a reverse current flows is connected to the parallel conductor at one end. And a stationary contact that is disposed on both the left and right sides of the parallel conductor portion and has the closed movable contact and an antiparallel conductor portion that is substantially parallel and through which current flows in the same direction. A pair of magnetic plates is arranged on the movable contact side so as to sandwich one end of the movable contact side of the movable contact from the left and right sides, and the distance between the magnetic plates constituting the pair of magnetic plates is Since the distance between each magnetic plate and the magnetic arc extinguishing plate provided opposite to one end of the movable contact is reduced, the height direction of the circuit breaker as described above Even when using a stationary contact configuration that can reduce the size of The effect of the magnetic field generated by the current in the row conductor can be shielded, the opening speed at the time of short-circuit current interruption is improved, excellent current limiting performance is obtained, and the electromagnetic that drives the arc to the arc extinguishing plate Since the force is strengthened and the shut-off time is shortened, there is an effect that an arc extinguishing chamber with reduced wear during shut-off can be obtained.
[0062]
In addition, an arc runner is provided at one end of the parallel conductor, and the fixed contact extends upward from the other end of the antiparallel conductor when the direction in which the movable contact is separated from the fixed contact is upward. The connecting conductor vertical portion is connected to the terminal portion, and the connecting conductor vertical portion is provided with a slit at a portion that intersects the surface including the locus during the opening / closing operation of the movable contact. Since the pair of magnetic plates are opposed to the pair of conductors constituting the connecting conductor vertical part, the magnetic field component that pushes back the arc caused by the current flowing through the connecting conductor vertical part between the contacts is shielded against the arc. This is advantageous in that it is difficult to cause interruption failure due to re-ignition.
[0063]
Furthermore, an arc runner is extended at one end of the parallel conductor, and the fixed contact extends upward from the other end of the antiparallel conductor when the direction in which the movable contact is separated from the fixed contact is upward. Since there is a connecting conductor vertical part connected to the terminal part and a magnetic shielding plate is arranged on the front surface of the connecting conductor part on the fixed contact side, the arc caused by the current flowing through the connecting conductor vertical part is pushed back between the contacts. The magnetic field component can be more reliably shielded against the arc, and there is an effect that it is difficult to cause a failure to shut off due to re-ignition.
[0064]
Furthermore, the connecting conductor vertical part is provided with a slit at a portion that intersects the plane including the locus during the opening / closing operation of the movable contact, and the pair of conductor parts constituting the right and left connecting conductor vertical parts of the slit are fixed. Since a pair of magnetic shielding plates are arranged on the front surface on the contact side, the magnetic field component that pushes back the arc caused by the current flowing through the connecting conductor vertical portion between the contacts is shielded against the arc, and the arc at the tip of the arc runner is There is an effect that a space for expansion can be ensured, and it is possible to obtain a material in which the interruption performance is hardly deteriorated due to insufficient arc expansion.
[0065]
Furthermore, an arc runner is extended to one end of the parallel conductor portion, and the tip of the arc runner is outside the space surrounded by the pair of magnetic plates, and the direction in which the movable contact is separated from the fixed contact is upward. Since the arc extinguishing plate made of a magnetic material is disposed in the upper space of the tip of the arc runner, the number of arc extinguishing plates that can be installed can be increased, and the arc division and cooling action by the arc extinguishing plate can be improved. The current interruption performance and the direct current interruption performance can be improved, and there is an effect that an increase in the internal pressure of the casing at the time of short circuit interruption can be reduced.
[0066]
Further, the fixed contact has a connecting conductor vertical portion extending upward from the other end of the antiparallel conductor portion and connected to the terminal portion, and a part of the plurality of magnetic arc extinguishing plates is extinguished. Since the arc plate is disposed between the connecting conductor vertical portion and the pair of magnetic plates, the magnetic field component that pushes back the arc generated by the current flowing through the connecting conductor vertical portion between the contacts is turned into the arc by the partial arc extinguishing plate. In contrast, it is possible to shield, and it is possible to obtain an object that is difficult to cause a failure of interruption due to re-ignition.
[0067]
Furthermore, an arc runner is extended at one end of the parallel conductor portion, and a protrusion is provided at a portion from the side next to the fixed contact of the insulating cover to the other end of the parallel conductor, and is surrounded by the protrusion. Since the space is in the form of a trumpet spreading toward the arc runner side, the arc is pushed from the fixed contact to the arc runner in an earlier time by the arc pressure reflection by the trumpet-like insulator wall and the vapor pressure of the insulating wall. Thus, there is an effect that the wear of the fixed contact is reduced, the interruption time is shortened, and a highly reliable one that can repeatedly perform the interruption operation is obtained.
[0068]
Furthermore, an arc runner is extended at one end of the parallel conductor portion, and a portion from the side next to the fixed contact of the insulating cover to the other end portion side of the parallel conductor portion is larger than the other portions by the heat of the arc. Since it is made of a material that generates steam, the arc generated between the contacts can be pushed out from the fixed contact to the arc runner by the driving force due to the pressure difference caused by the insulator vapor, and the movable cover is attached to the insulation cover. This is advantageous in that it is difficult to touch, and it is difficult to cause a failure to shut off due to dielectric breakdown through the creeping surface of the insulating cover.
[0069]
Further, an arc runner is extended to one end of the parallel conductor portion, and this arc runner, movable contact, fixed contact, a pair of magnetic plates and a magnetic arc extinguishing plate are accommodated in the case. Since a flow path communicating from the space near the tip of the arc runner is formed between the surface and the surface on the side opposite to the movable contact of the pair of magnetic plates, the front surface of the arc traveling through the arc runner is formed. An increase in pressure is suppressed, the arc traveling speed can be improved, and there is an effect that it is difficult to cause a failure of interruption due to the return of the metal vapor generated from the arc between the contacts.
[0070]
Furthermore, among the magnetic pieces that have a plurality of poles and form a pair of magnetic plates for each pole, the magnetic piece on the interpolar side is integrated with the adjacent magnetic piece of the other pole, so that The number of points can be reduced, and an inexpensive product can be obtained.
[Brief description of the drawings]
FIG. 1 is a diagram for explaining an arc extinguishing unit of a circuit breaker according to a first embodiment of the present invention.
FIG. 2 is a diagram for explaining main components in an arc extinguishing unit according to Embodiment 1 of the present invention.
FIG. 3 is a diagram for explaining a circuit breaker according to a first embodiment of the present invention.
FIG. 4 is a diagram for explaining the positional relationship and operation of main parts according to the first embodiment of the present invention.
FIG. 5 is a diagram for explaining the positional relationship and operation of main parts according to the first embodiment of the present invention.
FIG. 6 is a diagram for explaining the positional relationship and operation of main components according to Embodiment 2 of the present invention.
FIG. 7 is a diagram for explaining the positional relationship and operation of main components according to Embodiment 3 of the present invention.
FIG. 8 is a view for explaining a shielding plate according to a fourth embodiment of the present invention.
FIG. 9 is a view for explaining a pair of shielding plates according to a fifth embodiment of the present invention.
FIG. 10 is a view for explaining an insulating cover according to a sixth embodiment of the present invention.
FIG. 11 is a view for explaining an insulating cover according to a seventh embodiment of the present invention.
FIG. 12 is a diagram for explaining an internal configuration of an arc extinguishing unit according to an eighth embodiment of the present invention.
FIG. 13 is a diagram for explaining a multipolar circuit breaker according to a ninth embodiment of the present invention.
FIG. 14 is a diagram for explaining a conventional circuit breaker.
FIG. 15 is a view for explaining a stationary contact structure of another conventional circuit breaker.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Movable contact, 2 Movable contact, 5 Fixed contact, 6 Fixed contact, 7a Parallel conductor part, 7b Antiparallel conductor part, 7c Connection conductor perpendicular | vertical part, 8 Slit, 9 Archer, 10 A pair of magnetic board, 10a, 10b, 10c, 10d, 10e, 10f Magnetic body piece, 12 Insulating cover, 12d Projection part, 12e Part of insulating cover, 13 Arc extinguishing plate, 13b Some arc extinguishing plate, 15a Terminal part, 21, 22 Housing , 25 mechanical part, 30 shielding plate, 31 pair of shielding plates, 34 flow path

Claims

A movable contact having a movable contact at one end, a parallel conductor having a fixed contact forming a contact pair with the movable contact at one end, and being substantially parallel to the closed movable contact and flowing a reverse current; A fixed contact having an antiparallel conductor portion connected to the parallel conductor at one end and disposed on the left and right sides of the parallel conductor portion and the closed movable contact portion and a substantially parallel and unidirectional current flow; A pair of magnetic plates arranged to sandwich one end of the movable contact from the left and right sides of the antiparallel conductor portion on the movable contact side, an insulating cover that covers the surface of the magnetic plate on the movable contact side, A magnetic arc extinguishing plate provided opposite one end of the movable contact, a mechanism for closing or separating the movable contact from the fixed contact, and each of the pair of magnetic plates From the spacing between the magnetic plates, the arc extinguishing plate and each of the above Circuit breaker, wherein an interval of each of the sex material plate is small.

An arc runner is extended to one end of the parallel conductor, and when the direction in which the movable contact is separated from the fixed contact is upward, the fixed contact extends upward from the other end of the antiparallel conductor. The connecting conductor vertical part has a slit at a portion that intersects the surface including the locus during the opening / closing operation of the movable contact. 2. The circuit breaker according to claim 1, wherein a pair of magnetic plates are respectively opposed to the pair of conductor portions constituting the conductor vertical portion.

An arc runner is extended to one end of the parallel conductor, and when the direction in which the movable contact is separated from the fixed contact is upward, the fixed contact extends upward from the other end of the antiparallel conductor. 2. The circuit breaker according to claim 1, further comprising a connecting conductor vertical portion connected to the portion, and a magnetic shielding plate disposed on a front surface of the connecting conductor portion on the fixed contact side.

In the connecting conductor vertical portion, a slit is provided at a portion that intersects the plane including the locus during the opening / closing operation of the movable contact, and the fixed contact side of the pair of conductor portions constituting the left and right connecting conductors of this slit 4. The circuit breaker according to claim 3, wherein a pair of magnetic shielding plates are respectively disposed on the front surface of the circuit board.

An arc runner is extended to one end of the parallel conductor portion, and the tip of the arc runner is outside the space surrounded by the pair of magnetic plates, and when the direction in which the movable contact is separated from the fixed contact is upward, 2. The circuit breaker according to claim 1, wherein an arc extinguishing plate made of a magnetic material is disposed in an upper space at the tip of the arc runner.

The fixed contact has a connecting conductor vertical portion extending upward from the other end portion of the antiparallel conductor portion and connected to the terminal portion, and a part of the arc extinguishing plates of a plurality of magnetic materials. 6. The circuit breaker according to claim 5, wherein the circuit breaker is disposed between the connecting conductor vertical portion and the pair of magnetic plates.

An arc runner is extended at one end of the parallel conductor portion, and a protrusion is provided at a portion from the side next to the fixed contact of the insulating cover to the other end of the parallel conductor portion, and a space surrounded by the protrusion is formed. 2. The circuit breaker according to claim 1, wherein the circuit breaker has a trumpet shape extending to the arc runner side.

An arc runner is extended at one end of the parallel conductor portion, and a large amount of steam is generated from the other portion to the other end side of the parallel conductor portion by the heat of the arc from the side next to the fixed contact of the insulating cover. 2. The circuit breaker according to claim 1, wherein the circuit breaker is formed of a material that is generated.

An arc runner is extended to one end of the parallel conductor, and the arc runner, movable contact, fixed contact, a pair of magnetic plates and a magnetic arc extinguishing plate are housed in a housing, 2. The circuit breaker according to claim 1, wherein a flow path is formed between the pair of magnetic plates and the surface on the side opposite to the movable contact side from the space near the tip of the arc runner. .

Among the magnetic pieces having a plurality of poles and forming a pair of magnetic plates for each pole, the magnetic pieces on the interpolar side are integrated with the adjacent magnetic pieces of other poles. The circuit breaker according to claim 1.