【０００１】
【発明の属する技術分野】
本発明は、回路遮断器に関するものである。
【０００２】
【従来の技術】
近年、住宅の分岐回路に使用される回路遮断器には、一般に安全ブレーカと呼称される住宅用分電盤用配線用遮断器（ＪＩＳ Ｃ ８３７０参照）に代わって、分岐回路に接続される電気機器の電源コードが被覆の損傷や劣化によって短絡した場合のように比較的小さな短絡電流でも瞬時に電路を遮断し得るコード短絡保護用瞬時遮断機能付配線用遮断器（日本電機工業会規格 ＪＥＭ １４７７参照）が用いられている。
【０００３】
上記コード短絡保護用瞬時遮断機能付配線用遮断器（以下、「回路遮断器」と略す）は、従来の安全ブレーカよりも高感度の電磁釈放装置を備えており、その動作電流（電磁釈放装置が引外し動作を行う短絡電流の大きさ）が上記規格において３５０Ａを上限とし、ＪＩＳ Ｃ ８３７０に規定する越流試験にて引外し動作を行わない電流値を下限とする値に設定される。
【０００４】
このような回路遮断器としては特開２００２−２５４１５公報に記載されたものがある。この公報に記載されている従来例は、主回路に含まれる通電導体を間に挟むようにして固定鉄心及び可動鉄心が接離自在に配設されるとともに固定鉄心と可動鉄心を連結する板ばねにより可動鉄心が固定鉄心から離れる向きに付勢され、通電導体に短絡電流のような過大な電流が流れたときに固定鉄心と可動鉄心との間に生じる電磁吸引力で可動鉄心が固定鉄心に吸引され、板ばねのばね力に抗して可動鉄心が固定鉄心と接触する向きに移動することで開閉機構を釈放して主接点を強制的に開極するようにした電磁釈放装置を備えている。そして、この電磁釈放装置の動作電流は、図２７（ａ）に示すように越流（実線イ）のピーク値よりも大きく、且つコード短絡時に流れる比較的に小さな短絡電流（実線ロ）のピーク値よりも小さい値に設定される。なお、実線ハは回路短絡時に流れる大きな短絡電流を示している。
【０００５】
ここで、電磁釈放装置の動作を図２７を参照して簡単に説明する。なお、同図（ｂ）〜（ｅ）における横軸は時間、縦軸は固定鉄心と可動鉄心の間の距離をそれぞれ示している。まず、通電導体に越流が流れた場合、上述のように動作電流を越流よりも大きい値に設定していることから可動鉄心は移動せず、主接点は開極されない（同図（ｃ）参照）。一方、コード短絡による比較的に小さな短絡電流（以下、「コード短絡電流」と呼ぶ）が通電導体に流れた場合には、上述のように動作電流をコード短絡電流よりも小さい値に設定しているので、同図（ｄ）に示すようにコード短絡電流（同図（ａ）における実線ロ参照）が動作電流を超えた時点から可動鉄心が固定鉄心に吸引されて固定鉄心に接触する向きに移動し始め、コード短絡電流の上昇に伴って可動鉄心と固定鉄心の間の距離が狭くなり、両者の距離が所定値を下回ったときに開閉機構を釈放して主接点を強制的に開極する。なお、回路短絡による大きな短絡電流（以下、「短絡電流」と略す）が流れた場合には短絡電流がコード短絡電流よりも急激に上昇するから（同図（ａ）における実線ハ参照）、同図（ｅ）に示すようにコード短絡電流が流れた場合よりも短い時間で可動鉄心と固定鉄心との距離が上記所定値を下回って開閉機構を釈放して主接点を強制的に開極することになる。
【０００６】
【発明が解決しようとする課題】
しかしながら、モータあるいはインバータのようにその起動の際に瞬時に大きな突入電流が流れる負荷を分岐回路に接続した場合、図２７（ａ）の実線ニに示すように起動時の突入電流がコード短絡電流以上に流れると、電磁釈放装置の動作電流を超えてしまい、可動鉄心が固定鉄心に接触する向きに移動して突入電流の上昇に伴って可動鉄心と固定鉄心の間の距離が狭くなり、コード短絡等の異常が生じていないにもかかわらず、両者の距離が所定値を下回ったときに開閉機構を釈放して主接点を強制的に開極してしまうという問題があった。
【０００７】
本発明は上記問題に鑑みて為されたものであり、その目的は、負荷起動の際に瞬時に流れる突入電流により主接点が誤って強制開極されることを防止した回路遮断器を提供することにある。
【０００８】
【課題を解決するための手段】
請求項１の発明は、上記目的を達成するために、主回路を収納する器体と、少なくとも一部が器体から回動自在に露出するハンドルと、少なくともハンドルの操作に応じて主回路の主接点を開閉する開閉機構と、短絡電流が主回路に流れた場合に開閉機構を釈放して主接点を強制的に開極する電磁釈放装置とを備え、電磁釈放装置は、第１鉄心及び第２鉄心を具備し、主回路を形成する通電導体を間に挟む形で第１鉄心を第２鉄心に揺動自在に接離させるとともに第１鉄心を第２鉄心から離れる向きに付勢し第２鉄心が第１鉄心を吸引して第１鉄心と第２鉄心との距離が所定値を下回ったときに開閉機構を釈放してなる回路遮断器において、第２鉄心を第１鉄心と接離する方向に移動自在に配設するとともに、第１鉄心を第２鉄心から離れる向きに付勢する力よりも弱い力で第２鉄心を第１鉄心から離れる向きに付勢したことを特徴とし、通電導体に定格を超える電流が流れた場合には最初に第２鉄心が第１鉄心に接触する向きに移動した後に第１鉄心が第２鉄心に接触する向きに移動するため、短絡電流やコード短絡電流が流れたときには第１及び第２鉄心がそれぞれ電磁吸引力により互いに接触する向きに移動して主接点が強制開極されるが、負荷起動の際に瞬時に流れる突入電流は第１鉄心が移動し始める前に流れなくなることから第１鉄心と第２鉄心との距離が所定値を下回ることがなく、主接点が誤って強制開極されることを防止できる。
【０００９】
請求項２の発明は、請求項１の発明において、第２鉄心と通電導体との間に第２鉄心を第１鉄心から離す向きに弾性付勢する圧縮ばねを介装したことを特徴とし、圧縮ばねを第２鉄心の中心位置に当接させることが容易になるため、第２鉄心をスムーズに移動させることができる。
【００１０】
請求項３の発明は、請求項２の発明において、バイメタルからなる通電導体を一端で固定して他端を揺動自在としてなり、過負荷電流が通電導体に流れた場合に過負荷電流による温度上昇で通電導体の他端が揺動することにより開閉機構を釈放して主接点を強制的に開極する熱動釈放装置を備え、通電導体の中央から固定された一端側寄りの位置に圧縮ばねを介装したことを特徴とし、通電導体の他端が揺動する際の圧縮ばねと第２鉄心との間の距離の変動を抑えて圧縮ばねの位置ずれや脱落が防止できる。
【００１１】
請求項４の発明は、請求項１の発明において、第２鉄心と器体との間に第２鉄心を第１鉄心から離す向きに弾性付勢する圧縮ばねを介装したことを特徴とし、第２鉄心と圧縮ばねを器体内に配設した後に通電導体や第１鉄心を配設することができて組立作業が容易になる。
【００１２】
請求項５の発明は、請求項１〜４の何れかの発明において、主接点を閉極状態にラッチさせるラッチ部材と、器体内で揺動自在に配設され、主接点を開極状態へ移行させるラッチ部材の動きを規制するとともに電磁釈放装置が具備する第１鉄心と第２鉄心との距離が所定値を下回ったときに前記規制が解除される引外し部材とを開閉機構に具備し、引外し部材の揺動する部位に第１鉄心を取着したことを特徴とし、電磁釈放装置においては第１鉄心の動きを引外し部材に伝える部材が不要となり、部品点数を削減できるとともに第１鉄心と引外し部材との距離を縮めることで小型化が図れる。
【００１３】
請求項６の発明は、上記目的を達成するために、主回路を収納する器体と、少なくとも一部が器体から回動自在に露出するハンドルと、少なくともハンドルの操作に応じて主回路の主接点を開閉する開閉機構と、短絡電流が主回路に流れた場合に開閉機構を釈放して主接点を強制的に開極する電磁釈放装置とを備え、開閉機構は、主接点を閉極状態にラッチさせるラッチ部材と、器体内に揺動自在に配設されて主接点を開極状態へ移行させるラッチ部材の動きを規制するとともにラッチ部材の動きを規制する方向に付勢され、短絡電流が主回路に流れた場合に電磁釈放装置により前記規制を解除する方向に揺動させられる引外し部材とを具備し、電磁釈放装置は、引外し部材の揺動部位に対して固定鉄心と接離する方向に移動自在に設けた可動鉄心と、主回路を形成する通電導体を可動鉄心との間に挟む形で器体に固定した固定鉄心とを具備し、引外し部材をラッチ部材の動きを規制する方向に付勢する力よりも弱い力で可動鉄心を固定鉄心から離れる向きに付勢し、固定鉄心が可動鉄心を吸引して可動鉄心と固定鉄心との距離が所定値を下回ったときに引外し部材による前記規制を解除してなることを特徴とし、通電導体に定格を超える電流が流れた場合には最初に可動鉄心が引外し部材の揺動部位に対して固定鉄心に接触する向きに移動した後に引外し部材を揺動しながら可動鉄心が固定鉄心に接触する向きに移動するため、短絡電流やコード短絡電流が流れたときには可動鉄心が引外し部材を揺動しながら固定鉄心に接触する向きに移動して主接点が強制開極されるが、負荷起動の際に瞬時に流れる突入電流は可動鉄心が引外し部材を揺動しながら移動し始める前に流れなくなることから可動鉄心と固定鉄心との距離が所定値を下回ることがなく、主接点が誤って強制開極されることを防止できる。
【００１４】
請求項７の発明は、請求項６の発明において、棒状の主部の先端に鍔部を設けた取付部材を電磁釈放装置に具備し、可動鉄心を表裏に貫通し主部の径よりも大きく且つ鍔部の径よりも小さい径を有する貫通孔に取付部材の主部を挿通するとともに貫通孔に挿通した主部の後端を引外し部材の揺動部位に固定し、取付部材の主部に外挿した圧縮コイルばねを鍔部と可動鉄心との間に配置したことを特徴とし、圧縮コイルばねが鍔部と可動鉄心との間で取付部材の主部に支持されることとなり、圧縮コイルばねの脱落や座屈が防止できる。
【００１５】
請求項８の発明は、請求項７の発明において、複数の取付部材を電磁釈放装置に具備するとともに、各取付部材の主部を挿通する複数の貫通孔を可動鉄心に設けたことを特徴とし、引外し部材の揺動部位に対する可動鉄心の位置ずれを防止して特性を安定化させることができる。
【００１６】
請求項９の発明は、請求項７又は８の発明において、取付部材の主部の後端を挿抜自在に圧入する圧入孔を引外し部材の揺動部位に設けたことを特徴とし、圧縮ばねや可動鉄心を容易に交換することができる。
【００１７】
【発明の実施の形態】
（実施形態１）
以下、本発明を漏電遮断器に適用した実施形態１について図１〜図１５を参照して詳細に説明する。
【００１８】
本実施形態は、両側の合成樹脂製の第１側ケース１Ａと第２側ケース１Ｂとを連結して構成される器体１内に、器体１の幅方向に並設された２つの固定接点２Ａ，２Ｂと、これら各固定接点２Ａ，２Ｂに接離自在に対向する可動接点３Ａ，３Ｂを固着した２つの可動接触子４Ａ，４Ｂと、これらの２つの可動接触子４Ａ，４Ｂを駆動する開閉機構５とを備え、ハンドル６の投入・開放操作により開閉機構５を介して各可動接点３Ａ，３Ｂを各固定接点２Ａ，２Ｂに接離（接触・開離）させる構成となっており、各固定接点２Ａ，２Ｂ及び各可動接触子４Ａ，４Ｂを、器体１の高さ方向に上下に配設するとともに両可動接触子４Ａ，４Ｂの内、高さ方向で２つの固定接点２Ａ，２Ｂ間に介在する一方の可動接触子４Ｂと、他方の可動接触子４Ａの可動接点３Ａが接離する固定接点２Ａとを、各固定接点２Ａ，２Ｂから各可動接点３Ａ，３Ｂが開離した状態で器体１の幅方向から見て交差しない高さ位置に配設してある。
【００１９】
器体１の長手方向における一端部内には両側ケース１Ａ，１Ｂ間に挟み込むようにして、合成樹脂材料から成形された中間ケース７を固定しており、第１側ケース１Ａの側壁（外壁）内側の凹部８と中間ケース７の縦壁部３５とで構成される区画内に固定接点２Ａを一端に設けた電圧極側の出力端子を構成する端子ブロック１０Ａを収納し、中間ケース７の第２側ケース１Ｂ側に設けた凹部９と第２側ケース１Ｂの側壁（外壁）とで構成される区画内に下側の固定接点２Ｂを一端に設けた中性極側又は他方の電圧極側の出力端子を構成する端子ブロック１０Ｂを収納してある。
【００２０】
端子ブロック１０Ａは、コ状に折り曲げられた端子板１１と、該端子板１１の下片の一端より上方に延長片１１ａが一体延長され、該延長片１１ａの上端から延長片１１ａに対し直角に折り曲げて端子板１１に対して外向きに一体延長された固定接触子１２Ａと、該固定接触子１２Ａの一端上面にかしめ固定された固定接点２Ａと、端子板１１の下片上に載置されて端子板１１内に収納される略ム字状の鎖錠ばね１３Ａとで構成される。そして、上記第１側ケース１Ａの凹部８の下向き傾斜した底面上に端子板１１の下片を乗せ、凹部８の一端の立ち上がり壁８ａに沿うように延長片１１ａを配置し、立ち上がり壁８ａの上端を越えて固定接触子１２Ａを凹部８の外へ導出して立ち上がり壁８ａと、第１側ケース１Ａの底部より立ち上がった隔壁１４との間に凹部８の底部と同様に傾斜させて一体形成した固定接点配置部１５上に固定接触子１２Ａの先部を配置することにより、端子ブロック１０Ａが凹部８内に配設される。固定接点配置部１５には固定接触子１２Ａの下面側に突出した固定接点２Ａの下端を逃がす凹部１５ａが形成されている。端子板１１は上片の他端から上向きにＴ字片１１ｂを一体に延長形成しており、このＴ字片１１ｂの上端の側方突出部の片側先端を第１側ケース１Ａの内側面に形成してある凸平部２２の上端面に載置する。また端子板１１の側片の側面には鎖錠ばね１３Ａの押さえ片１３ｂ内に挿入され、鎖錠ばね１３Ａのがたつきを防止する突起２３を一体に形成してある。
【００２１】
鎖錠ばね１３Ａと端子板１１は導体接続部たる速結端子を構成するもので、第１側ケース１Ａに中間ケース７を重ね合わせた時に、第１側ケース１Ａの他端部の縦壁部に形成した断面が半円状の斜め下向き溝１６０と中間ケース７の対向壁面に形成した壁に同様な形状の斜め下向き溝１６０とで形成される斜め下向き電線挿入孔１６Ａを介して外部より挿入された電線（図示せず）の芯線が端子板１１の上片と鎖錠ばね１３Ａの鎖錠片１３ａの上端と押さえ片１３ｂの上端との間に圧入され、鎖錠片１３ａ先端により電線の引き抜き方向に対して芯線を鎖錠し且つ、押さえ片１３ｂの上端面で芯線を端子板１１の上片に押し付けることにより、電気的に芯線を接続すると共に、機械的に保持するようになっている。この電線鎖錠を解除するのが解除ハンドル１７でこの解除ハンドル１７は下部側面に設けた回動軸１８が第１側ケース１Ａの内側面の凸平部２２に設けた軸孔２０に回動自在に軸支され且つ中間ケース７の縦壁部３５の壁面に突出させている軸（図示せず）を下部他側面に設けた凹部３７に回動自在に軸支してあり、器体１の外側に露出する操作部１７ａを手動操作して回動させることで、下端に設けた駆動突起１９が鎖錠ばね１３Ａの鎖錠片１３ａの一側端の先部を押して鎖錠片１３ａを撓ませ、芯線に対する鎖錠を解除することができるようになっている。図中２１は解除ハンドル１７を常時反手動操作方向に回動付勢する復帰ばねである。
【００２２】
一方端子ブロック１０Ｂは、基本的に端子ブロック１０Ａと同様に端子板１１と、鎖錠ばね１３Ｂと、固定接触子１２Ｂとで構成されているが、端子ブロック１０Ａの端子板１１とは異なり、端子ブロック１０Ｂの端子板１１はその下片の一端より下向きに延長片１１ｃを延長形成し、その延長片１１ｃの先端より器体１の底部と平行するようにして固定接触子１２Ｂを延長形成し、また端子板１１の側片の一端部から直角に延長した奥片１１ｄを形成してある。
【００２３】
鎖錠ばね１３Ｂは、鎖錠ばね１３Ａと同じ構造のものであって、端子板１１の下片上に載置され、端子板１１の側片より突出させた突起２３が押さえ片１３ｂ内に挿入されようになっている。
【００２４】
この端子ブロック１０Ｂは中間ケース７の凹部９の底部を構成し器体１の底部に略平行に延出形成された横壁部２４上に端子板１１の下片を載置するともに、凹部９の一端部の縦壁２５に奥片１１ｄを沿わせるとともに縦壁２５の下端と、横壁部２４の一端部との間に形成された切欠２７に端子板１１の一端を嵌めて延長片１１ｃを凹部９外に出すようになっており、中間ケース７を第１側ケース１Ａ側に重ね合わせときに、固定接触子１２Ｂの先部、つまり固定接点２Ｂを設けた下面が第１側ケース１Ａの底部のリブ２６，２６上に載置されるようになっている。つまり固定接点２Ｂは中間ケース７の横壁部２４及び後述する膨出部３０及び両側ケース１Ａ，１Ｂの側壁間で構成される空間で両側ケース１Ａ，１Ｂ間に跨って配置される。尚リブ２６，２６間の凹所は固定接触子１２Ｂの先部にかしめ固定された固定接点２Ｂの固定接触子１２Ｂの下面側に突出した下端部の逃げとなる。
【００２５】
また端子板１１の上片の他端部より上方に延長形成されたＴ字片１１ｂの上端の側方突出部の先端は中間ケース７の壁面に形成してある凸平部２２’の上端面に載置される。
【００２６】
端子ブロック１０Ｂの鎖錠ばね１３Ｂと端子板１１は端子ブロック１０Ａの場合と同様に導体接続部たる速結端子を構成し、第２側ケース１Ｂに中間ケース７を重ね合わせたときに、中間ケース７の凹部９の他端部の縦壁部に設けられた断面半円状の斜め下向き溝１６０とこの斜め下向き溝１６０と同様に第２側ケース１Ｂの他端部の縦壁に設けられた斜め下向き溝１６０とで形成される電線挿入孔１６Ｂから電線が挿入されるとその芯線を鎖錠ばね１３Ｂの鎖錠片１３ａで鎖錠し、押さえ片１３ｂで芯線を端子板１１の上片に押しつけて電線を電気的に接続するともに機械的に鎖錠するようになっている。
【００２７】
この電線鎖錠を解除するのが解除ハンドル１７’で、この解除ハンドル１７’は上記の解除ハンドル１７と同様に下部側面に設けた回動軸１８が中間ケース７の凸平部２２’に設けた軸孔２０に回動自在に軸支され且つ第２側ケース１Ｂの内側壁面に突出させている軸３８を側面に形成してある凹部３７に回動自在に軸支し、器体１の外側に露出する操作部１７ａを手動操作して回動させたときに下端に設けた駆動突起１９が鎖錠ばね１３Ｂの鎖錠片１３ａの一側端の先部を押して鎖錠片１３ａを撓ませて鎖錠状態を解除することができるようになっている。図中２１’は解除ハンドル１７’を常時反手動操作方向に回動付勢する復帰ばねである。
【００２８】
中間ケース７は両側ケース１Ａ，１Ｂの側壁に略平行する縦壁部３５に対して第２側ケース１Ｂ側へ突出して第２側ケース１Ｂの側壁内面に当接する膨出部３０が形成され、この膨出部３０下面より垂下させた壁が上記縦壁２５であり、第２側ケース１Ｂ側に面する側壁、底壁、一端部の縦壁３２及び天井壁３３とで囲まれた凹所を第１側ケース１Ａ側に設けてある。そして第１側ケース１Ａ側に中間ケース７を突き合わせときに第１側ケース１Ａ側に組み付けてある端子ブロック１０Ａの固定接触子１２Ａの先端側部が凹所の底壁の段面上に載置され、また天井壁３３が第１側ケース１Ａの内側面より突出している横壁２９の下面に沿うよう配置される。また縦壁３２には固定接点２Ａに対応する可動接触子４Ａの自由端を凹所内に挿入するための開口部３９を形成してある。
【００２９】
一方器体１の長手方向における他端内部には、分電盤内において異なる位置（図２の上下方向）に各々配設された３本の導電バー（図示せず）の内で最下段の電圧極の導電バーを差込接続する１つの固定端子Ｔ１を収納配置する収納部９０と、最上段の中性極又は中段の他の電圧極の導電バーの何れかを選択して差込接続する１つの選択端子Ｔ２を中性極及び他の電圧極の導電バーに対応した少なくとも２つの位置間で移動自在に配設する内方収納部２００を設けてある。すなわち、本実施形態では選択端子Ｔ２を中性極の導電バーに接続すれば１００Ｖ、選択端子Ｔ２を他方の電圧極の導電バーに接続すれば２００Ｖの配電電圧に選択的に対応させることができる、いわゆる１００Ｖ／２００Ｖ兼用型となっている。
【００３０】
固定端子Ｔ１及び選択端子Ｔ２は共に略コ字状で、上下に並行する両側片の先部が互いに近接した後、先端にかけて拡開した刃受ばねから構成され、先端拡開により導電バーの差込を容易とし、中央の近接部位で導電バーを挟み込むようになっている。
【００３１】
内方収納部２００には、中性極及び電圧極の２本の導電バーに各々対応する２つの位置で選択端子Ｔ２を位置決めする位置決め手段として、第１側ケース１Ａの内方収納部２００を構成する区画の端部壁面に断面略半円状の突起９７を第１側ケース１Ａの幅方向に設けてある。
【００３２】
前記器体１の内方収納部２００の天井部に当たる壁には、選択端子Ｔ２が中性極又は電圧極の導電バーのうちのどちらに対応する位置にあるのか表示する表示手段として、内方収納部２００内に連通する通孔２０１を設け、この通孔２０１から選択端子Ｔ２を収納したスライド部材８３の上部に形成せる円柱状の表示部２０２が通孔２０１に臨んで外部から視認できるか、通孔２０１から離れた位置にあって外部から視認できないかにより選択端子Ｔ２の位置を知ることができるようになっている。また通孔２０１を介してスライド部材８３を外部から押し操作して下方移動させることも可能としている。この通孔２０１は両側ケース１Ａ、１Ｂの上面側壁に設けた半円の切欠孔２０１ａが突き合わせられて形成される円形の孔からなる。
【００３３】
スライド部材８３は合成樹脂成形品からなり器体１の両端方向に対応する両端面が開口した枠体状に形成されたもので、選択端子Ｔ２を構成する刃受ばねを一端開口から挿入して他端開口より刃受ばねの先端部を突出させるようにして保持しており、選択端子Ｔ２はこのスライド部材８３と共に内方収納部２００内を図２において上下方向に移動自在に配置される。
【００３４】
内方収納部２００の両側壁を構成する両側ケース１Ａ，１Ｂの側壁の内面にはスライド部材８３の両側部に形成したスライド突起２０３を上下移動自在に係合してスライドさせる上下方向のガイド溝２０４を２条の並行する突起２０５間に形成しており、内方収納部２００はこの両側壁のガイド溝２０４，２０４にスライド部材８３の両側のスライド突起２０３を係合した状態でスライド部材８３とともに選択端子Ｔ２を上下方向にスライド移動自在に収納保持している。なお、内方収納部２００側にスライド突起を、ガイド溝をスライド部材８３側に設けても良い。
【００３５】
スライド部材８３は第１側ケース１Ａの側部より図１に示すように図において下方に延びた脚片８３ａを一体に延長形成するとともに、脚片８３ａの下端部には外向きに突出した突出部２０６を形成してある。
【００３６】
この突出部２０６は内方収納部２００の側壁を構成する第１側ケース１Ａの側壁の外側に、図２に示すように第１側ケース１Ａの底面から上方向に形成されたスライド溝２０７の上端底部に内方収納部２００と連通するように開口した挿通孔（図示せず）からスライド溝２０７内に挿入されて脚片８３ａとともにスライド溝２０７内を上下方向にスライド自在に位置される。
【００３７】
スライド溝２０７、挿通孔は選択端子Ｔ２を装着したスライド部材８３を上下移動させるためのガイド部を構成しており、スライド溝２０７の底部は内方収納部２００内に突出するように形成され、スライド溝２０７の上端底部に形成された挿通孔を介してスライド溝２０７内に上方挿入される脚片８３ａの裏面がスライド溝２０７の底部に摺接可能なようになっている。またスライド溝２０７の最上方には突出部２０６がスライド溝２０７の上端部へ移動したときに衝合する突出部２０７ａを設けてある。
【００３８】
而して、突出部２０６が内方収納部２００内の選択端子Ｔ２を上下移動させる操作部を構成し、器体１外部からこの突出部２０６を持って或いはドライバ等で押し上げたり、押し下げることによってスライド溝２０７内をスライド移動させれば、このスライド移動に伴い内方収納部２００内のスライド部材８３が選択端子Ｔ２と共にスライド突起２０３とガイド溝２０４とによるガイドによって上又は下へ移動することになる。
【００３９】
上記の操作によってスライド部材８３が移動する際、位置決め突起９７をスライド部材８３の先端上部或いは先端下部がその弾性と位置決め突起９７のアール面とにより乗り越え、移動後は位置決め突起９７に枠部８３の先端下部或いは先端上部が当たって、選択端子Ｔ２の位置を保持するようになっている。
【００４０】
さて可動接触子４Ａ，４Ｂを開閉駆動する開閉機構５は、ラッチ部材たる作動板４３と、クロスバー４０と、作動板４３の一端を係止する段状の係止部４１ｅを備えた第１引外し板４１と、第２引外し板４２と、ハンドル６と、コ字状リンク４４等からなる。そして、一方の主接点（固定接点２Ａ及び可動接点３Ａ）の閉極状態において地絡事故や短絡事故により異常な大電流が流れれば第１の電磁釈放装置４７Ａによって、他方の主接点（固定接点２Ｂ及び可動接点３Ｂ）の閉極状態において同じく地絡事故や短絡事故により異常な大電流が流れれば第２の電磁釈放装置４７Ｂによって、主回路に漏洩電流が流れれば漏電保護用の第３の電磁釈放装置４８によって、さらに過負荷電流のような過電流が流れれば熱動釈放装置によって、それぞれ開閉機構５を釈放して主接点を強制的に開極させる。
【００４１】
ハンドル６は、操作部６ａと回動部６ｂとハンドル軸６ｃとで構成され、回動部６ｂの両側面の中央に突出したハンドル軸６ｃを第１側ケース１Ａの内側面に形成された軸孔４９と、第２側ケース１Ｂの内側面に形成された軸孔４９とにそれぞれ回動自在に挿入して両側ケース１Ａ，１Ｂ間に保持され、操作部６ａは、両側ケース１Ａ，１Ｂの連結した状態で構成される器体１の上面に開口する窓孔５０に臨むようになっている。またハンドル軸６ｃにはねじりばね３６が装着され、ねじりばね３６により、ハンドル６は投入操作位置（図２及び図３参照）において、開放操作方向に付勢されている。
【００４２】
回動部６ｂの下端に設けた軸孔６ｄにはコ字状リンク４４の上側軸４４ａを回動自在に挿入して、コ字状リンク４４を介して作動板４３と連結されている。
【００４３】
作動板４３は中央両側に設けた軸受け孔４３ａにコ字状リンク４４の下側軸４４ｂを貫挿させることによりコ字状リンク４４を介してハンドル６と連結され、器体１内に上下移動自在に配置される。
【００４４】
クロスバー４０は上部の両側面に突出させた軸４０ａを両側ケース１Ａ，１Ｂの内側面に形成した軸孔５２、５２に挿入して両側ケース１Ａ，１Ｂ間に枢支されるもので、図２に示すように軸４０ａよりやや下方の第１側ケース１Ａ側の側部には可動接触子４Ａの側部を横方向から嵌める切溝５４を、また図１に示すように下部の第２側ケース１Ｂ側の側部には可動接触子４Ｂを横方向から嵌める切溝５５をそれぞれ設けてある。そして可動接点側端面には、中間ケース７及び第１側ケース１Ａの側壁の内面に突設してある止片１３０を、各可動接点３Ａ，３Ｂが各固定接点２Ａ，２Ｂから開離した状態で係入してその底部に当接する凹溝１３１を幅方向に形成してある（図３参照）。
【００４５】
ここで可動接触子４Ａは剛体の導電金属板から構成され、クロスバー４０の切溝５４に側方から挿入されるとともに、切溝５４の後ろに設けた凹み部４０ｂ（図３参照）において、後部下面と凹み部４０ｂの底部との間に圧縮配置される接圧用のコイルばね５３により後部が上方に付勢されるようになっており、クロスバー４０が軸４０ａを中心として回動したときに可動接触子４Ａは切溝５４の開口縁を中心として回動し、自由端にかしめ固定した可動接点３Ａを対応する固定接点２Ａに対して開離・接触させるようになっている。
【００４６】
また可動接触子４Ｂは導電性ばね薄板材からなり、クロスバー４０が投入動作方向に回動したときには下方に押されて撓み、この撓んだ状態からクロスバー４０が開放動作方向に回動したときには復帰し、その撓みと、復帰とで、先端にかしめ固定した可動接点３Ｂを固定接点２Ｂに対して接触・開離させるようになっている。
【００４７】
クロスバー４０の下端部は、該下端部と、第１側ケース１Ａの底部より垂立させた壁６３との間で圧縮配置されたコイルばね６２により押されて回転力が付与される。
【００４８】
図５に示すように、第１引外し板４１は軸部４１ａと、この軸部４１ａの上部に突出する突出部４１ｂと、軸部４１ａの下部に突出する一対の脚部４１ｃ，４１ｄとからなり、軸部４１ａの両端を両側ケース１Ａ，１Ｂの内側面に設けられた軸孔５６、５６に挿入して両側ケース１Ａ，１Ｂ間で回動自在に支持されるとともに、ねじりばね８１によって突出部４１ｂがバイメタル４５から離れる向き（図２における時計回り）に弾性付勢される。突出部４１ｂの上端部には作動板４３の一端が係脱する係止部４１ｅを形成し、一方の脚部４１ｃの先端側面には後述するバイメタル４５に押し駆動される受け部４１ｇを突設するとともに、他方の脚部４１ｄの先端側面には第２の引外し板４２に押し駆動される受け部４１ｆを突設している。
【００４９】
第２引外し板４２は軸孔４２ｂを有する中央部から対向部４２ａ並びに受け部４２ｃが突出した略へ字形に形成され、後述する隔壁部材３１に設けられた軸３１ｆを軸孔４２ｂに挿入して回動自在に枢支される。また対向部４２ａの端面には、後述するバイメタル４６の下端に対向し、バイメタル４６の湾曲時に押される駆動片４２ｄが設けてある。
【００５０】
厚板金属材からなる導電板７１Ａ，７１Ｂは、図１及び図５に示すように一端部側に調整螺子７７，７７’が螺合するねじ孔７１ａが貫設され、他端部の下面側に一対のかしめ軸７１ｂが突設されている。そして、熱動釈放装置を構成するバイメタル４５，４６をそれぞれ一端側に溶着固定して垂下させた薄板金属材からなる調整板７２，７２’が、その他端側に貫設された一対の孔７２ａにかしめ軸７１ｂを挿通してかしめることで導電板７１Ａ，７１Ｂの下面側にそれぞれ取り付けられている。
【００５１】
一方のバイメタル４５の調整板７２との固定部分には固定端子Ｔ１に一端が溶着された編組線７９Ａの他端が溶着され、後述する第１の回路基板７３に一端が接続されたリード線８２Ａが溶着されるとともに、一端が可動接触子４Ａに溶着された編組線７９Ｄの他端がバイメタル４５の略中央部に溶着され、固定端子Ｔ１，編組線７９Ａ，導電板７１Ａ，バイメタル４５，編組線７９Ｄ，可動接触子４Ａが電気的に接続されている。また、他方のバイメタル４６の調整板７２’との固定部分には選択端子Ｔ２に一端が溶着された編組線７９Ｂの他端が溶着されるとともに、可動接触子４Ｂに連結された通電導体８０（後述する）に一端が溶着された編組線７９Ｃの他端がバイメタル４６の略中央部に溶着され、選択端子Ｔ２，編組線７９Ｂ，導電板７１Ｂ，バイメタル４６，編組線７９Ｃ，通電導体８０，可動接触子４Ｂが電気的に接続されている。なお、調整螺子７７，７７’を螺進させることで調整板７２，７２’と導電板７１Ａ，７１Ｂとの距離を変化させ、バイメタル４５，４６の下端位置、すなわち熱動釈放装置の感度が調整可能となっている。
【００５２】
ところで、導電板７１Ａ，７１Ｂ並びにバイメタル４５，４６は隔壁部材３１に保持される。この隔壁部材３１は絶縁性を有する合成樹脂成型品からなり、２つのバイメタル４５，４６を隔絶する平板状の隔壁３１ａと、隔壁３１ａの周縁よりその厚み方向（器体１の幅方向）両側へ突出する周壁３１ｂとを有し、隔壁３１ａ並びに周壁３１ｂに囲まれた各凹所３１ｃ，３１ｃに導電板７１Ａとバイメタル４５並びに導電板７１Ｂとバイメタル４６がそれぞれ収納される。凹所３１ｃ，３１ｃ上部の周壁３１ｂには複数の突起３１ｄが対向して突設されており、これらの突起３１ｄ間に導電板７１Ａ，７１Ｂを圧入することで導電板７１Ａ，７１Ｂ並びにバイメタル４５，４６を隔壁部材３１に保持させている（図２及び図３参照）。また、導電板７１Ａ，７１Ｂを収納した凹所３１ｃ，３１ｃの上部周壁３１ｂには、調整螺子７７，７７’を凹所３１ｃ，３１ｃの外へ臨ませるために矩形の切り欠き３１ｅ，３１ｅが形成してある。さらに、導電板７１Ｂ及びバイメタル４６を収納する側の凹所３１ｃ底部には第２引外し板４２の軸孔４２ｂに挿入する軸３１ｆが突設してある。
【００５３】
第１の電磁釈放装置４７Ａは、図５に示すように磁性鉄板を長さの異なる一対の側片６０ａ，６０ｂを有する平面視略コ字型に折曲してなる第２鉄心６０と、矩形平板状の磁性鉄板からなる第１鉄心６１とで構成される。第２鉄心６０は、導電板７１Ａを収納した凹所３１ｃ側の周壁３１ｂに形成された段部３１ｇに載置されるとともに隔壁３１ａに設けられた凹溝３１ｈに一方（短い方）の側片６０ａを前後方向（図２における左右方向）において移動自在に嵌合する形で凹所３１ｃ内に収納され、バイメタル４５と周壁３１ｂとの間に配置される（図２参照）。一方、第１鉄心６１は厚み方向に貫通する一対の貫通孔６１ａが形成され、第１引外し板４１の突出部４１ｂの上端部における係止部４１ｅと反対側の面に突設された一対の突起４１ｈを貫通孔６１ａに挿通してかしめることにより第１引外し板４１に取着され、図２に示すように第２鉄心６０の他方（長い方）の側片６０ｂの先端である磁極面と対向する。ここで、第２鉄心６０の側片６０ａ，６０ｂにおいてバイメタル４５と対向する部位に円柱形のばね座６０ｃが突設され、このばね座６０ｃと対向するバイメタル４５の長手方向中央から固定された一端（図５における上端）側寄りの位置にも同様に円柱形のばね座４５ａが突設されており、これら２つのばね座６０ｃ，４５ａに圧縮コイルばねからなる復帰ばね６４の両端部がそれぞれ外挿されて第２鉄心６０とバイメタル４５との間に復帰ばね６４が介装されている。すなわち、第２鉄心６０は一方の側片６０ａを凹溝３１ｈに嵌合した状態で第１鉄心６１と接離する方向（図２における左右方向）に移動自在であり、且つ復帰ばね６４によって第１鉄心６１から離れる向きに弾性付勢されている。なお、復帰ばね６４のばね力を第１引外し板４１を弾性付勢するねじりばね８１のばね力よりも弱く設定することによって、第１鉄心６１を第２鉄心６０から離れる向きに付勢する力（ねじりばね８１のばね力）よりも弱い力で第２鉄心６０を第１鉄心６１から離れる向きに付勢している。なお、このように第２鉄心６０とバイメタル４５との間に第２鉄心６０を第１鉄心６１から離す向きに弾性付勢する復帰ばね６４を介装すれば、復帰ばね６４を第２鉄心６０の中心位置に当接させることが容易になるために第２鉄心６０をスムーズに移動させることができる。また、バイメタル４５の中央から固定された一端側寄りの位置にばね座４５ａを設けて復帰ばね６４を取り付けているので、バイメタル４５の他端が揺動する際の復帰ばね６４と第２鉄心６０との間の距離の変動を抑えて復帰ばね６４の位置ずれや脱落が防止できるという利点がある。
【００５４】
而して、主接点（固定接点２Ａ及び可動接点３Ａ）を含む一方の極の通電導体であるバイメタル４５にコード短絡や回路短絡による異常な大電流が流れたときに第２鉄心６０の側片６０ｂの磁極面と第１鉄心６１との間に発生する電磁吸引力により、まず第２鉄心６０が復帰ばね６４のばね力に抗して第１鉄心６１に近付く向きに移動し、側片６０ａが凹溝３１ｈの端面に当接する位置まで第２鉄心６０が移動した後にさらに電磁吸引力により第１鉄心６１を第２鉄心６０に近付く向きに吸引揺動させ、第１鉄心６１が取着された第１引外し板４１を、図２における反時計回りに回動させるのである。なお、このように第１鉄心６１を第１引外し板４１に取着することにより、第１鉄心６１の動きを第１引外し板４１に伝える部材（例えば、第２の電磁釈放装置４７Ｂにおける第２引外し板４２のようなもの）が不要となり、部品点数を削減できるとともに第１鉄心６１と第１引外し板４１との距離を縮めることで小型化が図れるものである。
【００５５】
第２の電磁釈放装置４７Ｂは、図６に示すように磁性鉄板を平面視略コ字型に折曲してなる固定鉄心５７と、矩形平板状の磁性鉄板からなる可動鉄心５８と、可動鉄心５８を固定鉄心５７の両端磁極面に揺動自在に対向支持させ且つ可動鉄心５８を固定鉄心５７から離れる向きに弾性付勢する弾性部材たる板ばね５９とで構成される。また、通電導体８０は先端部に編組線７９Ｃの一端が溶着される内片８０ａと、内片８０ａの後端より略Ｌ字形に延出されて内片８０ａと略平行に対向する外片８０ｂとで構成され、外片８０ｂの先端部に可動接触子４Ｂの後端部が連結される。
【００５６】
可動鉄心５８は固定鉄心５７側の面に突出させた突起５８ａ，５８ａを、板ばね５９の中央片５９ａの一端部に形成した孔５９ｂ，５９ｂに挿入してかしめ固定することで板ばね５９に揺動自在に支持される。一方、板ばね５９は中央片５９ａの両側方に折り曲げ形成した両側片５９ｃ，５９ｃを固定鉄心５７の両側片５７ａ，５７ａの外面に沿わせるように配置して両側片５９ｃ，５９ｃの先端に内向きに突出させた係止片５９ｄ，５９ｄを、固定鉄心５７の外側角部に形成した凹部５７ｂ，５７ｂに係止させることにより、図７に示すように通電導体８０の内片８０ａを固定鉄心５７と可動鉄心５８の間に介在させ、内片８０ａと外片８０ｂの間に可動鉄心５８を挟む形で固定鉄心５７に固持される。このとき、固定鉄心５７の両側片５７ａ，５７ａの先端である磁極面が板ばね５９の中央片５９ａと、両側片５９ｃ，５９ｃとの間を介して可動鉄心５８に対向する。
【００５７】
而して、他方の極の主接点を構成する可動接点３Ｂと電気的に接続される通電導体８０に回路短絡による短絡電流のような異常な大電流が流れたときに固定鉄心５７の両側片５７ａ，５７ａの磁極面に発生する電磁吸引力により可動鉄心５８を吸引揺動させるのである。なお、このように固定鉄心５７と可動鉄心５８を板ばね５９で連結してブロック化しているため、後述するように第２の電磁釈放装置４７Ｂの器体１への組み込み作業が容易になるものである。
【００５８】
ここで通電導体８０の内片８０ａに流れる電流によって固定鉄心５７の両側片５７ａ，５７ａの磁極面に発生する電磁吸引力の向きと、外片８０ｂに流れる電流によって固定鉄心５７の両側片５７ａ，５７ａの磁極面に発生する電磁吸引力の向きとを同一とし、可動鉄心５８を吸引する電磁吸引力を強めて主接点を素早く開極するようにしている。
【００５９】
一方、第３の電磁釈放装置４８は、第２の電磁釈放装置４７Ｂの固定鉄心５７に励磁用のコイル６８を巻装して構成される。すなわち、図６に示すように合成樹脂のような絶縁材料により一側面が開放した角筒状に形成されたコイルボビン６９を、軸方向両端から固定鉄心５７の側片５７ａ，５７ａをそれぞれ突出するようにして固定鉄心５７に装着し、図７に示すようにコイルボビン６９の軸方向両端部に設けた外鍔６９ａ，６９ａ間にコイル６８が巻回してある。なお、コイルボビン６９の外鍔６９ａ，６９ａの開放された側面近傍には挿着孔６９ｃが貫設された略立方体形の支持部６９ｂ，６９ｂが突設され、略Ｌ字形の端子ピン６９ｄの一端部が挿着孔６９ｃにそれぞれ挿着されており、挿着孔６９ｃから突出する端子ピン６９ｄの一端部にコイル６８の端末６８ａがそれぞれからげて電気的に接続してある。
【００６０】
而して、地絡事故によって漏洩電流が流れたときに後述する漏電保護回路５１により端子ピン６９ｄを介してコイル６８に通電して固定鉄心５７を励磁し、固定鉄心５７の両側片５７ａ，５７ａの磁極面に電磁吸引力を発生させて可動鉄心５８を吸引揺動させるのである。つまり、固定鉄心５７にコイル６８を巻装することで第２の電磁釈放装置４７Ｂを構成する固定鉄心５７，可動鉄心５８，板ばね５９を漏電保護用の第３の電磁釈放装置４８に兼用することができるから、各極毎の大電流保護用の電磁釈放装置と漏電保護用の電磁釈放装置とを独立した部品で構成する場合に比較して、部品点数を削減することができて省スペース化並びに小型化が図れるものである。
【００６１】
また、固定鉄心５７と可動鉄心５８との間におけるコイル６８並びに通電導体８０（内片８０ａ）の通電方向が一致するため、コイル６８に通電されて第３の電磁釈放装置４８が動作した場合に固定鉄心５７の両側片５７ａ，５７ａの磁極面に発生する電磁吸引力を強めることができ、主接点を素早く開極させることができる。さらにコイル６８を固定鉄心５７に巻装しているため、コイル６８が移動しないことからコイル６８の断線を防ぐことができる。但し、可動鉄心５８にコイル６８を巻装してもよい。
【００６２】
漏電保護回路５１は図８に示す回路構成を有するものであって、主回路の電圧極の電路（編組線７９Ａ）と中性極又は他方の電圧極の電路（編組線７９Ｂ）が貫挿された零相変流器ＺＣＴを備え、地絡電流等の漏洩電流によって主回路の各極に流れる電流が不平衡となると零相変流器ＺＣＴの出力端子間に不平衡度合いに応じた電流（検出電流）が流れる。この検出電流は交番電流であって、逆並列に接続したダイオードＤ１，Ｄ２からなるクランプ回路でクランプされ、抵抗Ｒ１を介して平滑コンデンサＣ１を充電することにより検出電流を電圧に変換する。そして、平滑コンデンサＣ１の両端電圧、すなわち検出電流から変換された検出電圧が漏洩電流判定回路５１ａに入力される。
【００６３】
漏洩電流判定回路５１ａの電源は、端子ピン６９ｄから第３の電磁釈放装置４８のコイル６８を通して、ダイオードＤ３、抵抗Ｒ２〜Ｒ５、平滑コンデンサＣ２の直列回路を主回路の２つの極の間に接続し、平滑コンデンサＣ２の両端電圧を漏洩電流判定回路５１ａの電源端子及び接地端子に印加することで得られる。また、主回路の２つの極の間には、コイル６８とサイリスタＳＣＲとダイオードＤ３の直列回路が接続され、漏洩電流判定回路５１ａの出力端子から出力する制御信号をサイリスタＳＣＲのゲートに印加することでサイリスタＳＣＲをターンオンさせる。なお、サイリスタＳＣＲの両端間にはコンデンサＣ０と抵抗Ｒ０からなるフィルタ回路が接続されている。
【００６４】
漏洩電流判定回路５１ａは、上記検出電圧を所定の閾値と比較し、比較結果に応じてコンデンサＣ３を充電又は放電し、コンデンサＣ３の両端電圧に応じて出力端子から制御信号を出力することによって比較結果を遅延するように構成してある。したがって、主回路に漏洩電流が流れると制御信号によってサイリスタＳＣＲがターンオンし、コイル６８に通電されることによって第３の電磁釈放装置４８が動作し、可動鉄心５８が固定鉄心５７に吸引される。漏洩電流判定回路５１ａは集積回路よりなり、上記コンデンサＣ３並びに漏電検出後にコンデンサＣ３を放電するための時定数を決める抵抗Ｒ６が外付けされる。
【００６５】
また、主回路の２つの極の間には、抵抗ＲＴ、常開のテストスイッチＳＷ並びに零相変流器ＺＣＴに貫挿されたリード７０ａの直列回路からなる試験回路７０が接続される。すなわち、テストスイッチＳＷをオンしてリード７０ａに電流を流すことにより零相変流器ＺＣＴの１次側に不平衡電流を流して擬似的に漏電状態を作り出し、漏電保護回路５１が正常に動作するか否かの試験を行うことができる。なお、抵抗ＲＴ並びにテストスイッチＳＷにはサージ吸収素子ＳＡが並列に接続してある。
【００６６】
ところで、漏電保護回路５１並びに試験回路７０を構成する上記複数種の回路部品は、図９に示すようにプリント配線基板からなる第１及び第２の回路基板７３，７４に実装される。第１の回路基板７３には図８の回路図中に点線で示した境界線Ｗから左側の強電系の回路を構成する強電系の回路部品（抵抗Ｒ２，Ｒ３、ダイオードＤ３、試験回路７０、フィルタ回路等）が実装され、第２の回路基板７４には境界線Ｗから右側の弱電系の回路を構成する弱電系の回路部品（漏洩電流判定回路５１ａ、クランプ回路、平滑コンデンサＣ１、零相変流器ＺＣＴ等）並びにサイリスタＳＣＲが実装される。テストスイッチＳＷは、一端が第１の回路基板７３に接合されて揺動自在に支持された可動接点板７６ａと、可動接点板７６ａに対向するように第１の回路基板７３に実装されたピン状の固定接点７６ｂとで構成され、可動接点板７６ａの自由端側の上部に移動自在に配設されるテスト釦７８を押操作している場合に、テスト釦７８に押駆動された可動接点板７６ａが固定接点７６ｂに接触してオンするものである。
【００６７】
零相変流器ＺＣＴは、図９に示すように巻線（図示せず）を巻回したリング形のコア（図示せず）を合成樹脂成型品のハウジング７５に納装したものであって、コアの軸方向に対向するハウジング７５の側面端部から突出する一対の出力端子７５ａが第２の回路基板７４の上部に設けた切り欠き７４ａ，７４ａに挿通され、ハウジング７５を第２の回路基板７４の表面にほぼ密着させた状態で出力端子７５ａを裏面の配線パターン（図示せず）に半田付けして実装される。
【００６８】
また、零相変流器ＺＣＴのハウジング７５には、図９に示すように第１及び第２の回路基板７３，７４を取り付けるための複数の取付部たるコンタクトピン６７1〜６７5が軸方向の両側面より突設されている。これらのコンタクトピン６７1〜６７5は金属製であってその軸方向を零相変流器ＺＣＴの軸方向に一致させ且つ両端部をハウジング７５の側面から各々突出させてハウジング７５にインサート成型され、第１の回路基板７３と対向する側面側にはコンタクトピン６７1〜６７5をその先端部を残して被うボス部７５ｃがハウジング７５と一体に形成されている。
【００６９】
一方、第１及び第２の回路基板７３，７４には各コンタクトピン６７1〜６７5を挿通するスルーホール７３ａ，７４ｂがそれぞれ穿孔されており、各スルーホール７３ａ，７４ｂに挿通したコンタクトピン６７1〜６７5の端部を配線パターンに接合することにより、第１及び第２の回路基板７３，７４が零相変流器ＺＣＴの厚み方向（軸方向）の両側面に振り分けて取り付けられる。このとき、コンタクトピン６７1〜６７4が２つの回路基板７３，７４間の通電路を兼ね、コンタクトピン６７1〜６７5を介して第１及び第２の回路基板７３，７４に実装された回路部品が電気的に接続される。また、第１の回路基板７３の下部には第３の電磁釈放装置４８を構成する端子ピン６９ｄがそれぞれ挿通されるスルーホール７３ｂが穿孔されており、各スルーホール７３ｂに挿通した端子ピン６９ｄの端部を配線パターンに接合することでコイル６８が漏電保護回路５１に電気的に接続される。さらにハウジング７５の中央に開口する貫通孔７５ｂの近傍にコンタクトピン６７5が設けてあり、このコンタクトピン６７5が零相変流器ＺＣＴのコアを貫挿する試験回路７０のリード７０ａとなる。なお、第１及び第２の回路基板７３，７４にはハウジング７５の貫通孔７５ｂに連通して編組線７９Ａ，７９Ｂが挿通される円形の挿通孔７３ｃ，７４ｃが設けてある。また、第１の回路基板７３には導電板７１Ａを介して主回路の一方の極（固定接点２Ａ及び可動接点３Ａの主接点を有する極）に接続するリード線８２Ａの一端と、主回路の他方の極（固定接点２Ｂ及び可動接点３Ｂの主接点を有する極）に接続するための接続部材９９に一端が溶着されたリード線８２Ｂの他端とが接続されている。
【００７０】
而して、漏電保護回路５１を構成する複数種の回路部品を第１及び第２の回路基板７３，７４に実装し、零相変流器ＺＣＴの厚み方向両側に第１及び第２の回路基板７３，７４を配置して器体１に収納するため、従来のように１枚の回路基板に漏電保護回路５１と零相変流器ＺＣＴを実装する場合に比較して各回路基板７３，７４の長手方向の寸法を小さくでき、器体１の小型化が図れるものである。また、零相変流器ＺＣＴのハウジング７５に取付部たるコンタクトピン６７1〜６７5を設けることにより、第１及び第２の回路基板７３，７４に零相変流器ＺＣＴを容易に取り付けることができる。さらに、取付部を金属製のコンタクトピン６７1〜６７4とし、第１及び第２の回路基板７３，７４間を電気的に接続する通電路としているので、別途リード線等を用いて配線する場合に比較して回路基板７３，７４間の通電路が簡単に形成できるという利点があり、しかもコンタクトピン６７1〜６７5をハウジング７５にインサート成型することで零相変流器ＺＣＴの巻線と絶縁することができる。
【００７１】
また、コンタクトピン６７5を試験回路７０のリード７０ａとしているため、第１及び第２の回路基板７３，７４を零相変流器ＺＣＴに取り付けることで試験回路７０のリード７０ａを零相変流器ＺＣＴのコアに簡単に貫挿させることができる。さらに、第１の回路基板７３には強電系の回路を構成する強電系の回路部品を実装し、第２の回路基板７４には主に弱電系の回路を構成する弱電系の回路部品を実装しているため、強電系に比較して絶縁距離を短くできる弱電系の回路部品を主に実装した第２の回路基板７４により多くの回路部品を実装することができる。ここで、主回路の一方の極に接続するためのリード線８２Ａと他方の極に接続するためのリード線８２Ｂが強電系の回路部品を実装した第１の回路基板７３に接続してあるため、第２の回路基板７４においてはリード線８２Ａ，８２Ｂの接続位置からの絶縁距離を考慮せずに回路部品を配置することができるという利点がある。
【００７２】
而して、本実施形態の漏電遮断器を組み立てるに当たっては、まず第１側ケース１Ａの凹部８に端子ブロック１０Ａを収納するとともに解除ハンドル１７を復帰ばね２１とともに定位置に組み込む。またハンドル６を所定位置にねじりばね３６とともに組み込む。そして、クロスバー４０を、切溝５４に可動接触子４Ａを嵌め込むとともにコイルばね５３を凹部内に収納し、第１側ケース１Ａの所定位置にコイルばね６２とともに回動自在に配置する。また作動板４３をリンク４４でハンドル６と連結させて配設する。
【００７３】
さらに、器体１の他端底部に設けた収納部９０に固定端子Ｔ１を収納するとともに、スライド部材８３と一緒に選択端子Ｔ２を、第２側ケース１Ｂと突き合わせたときに構成される内方収納部２００に対応する第１側ケース１Ａの内側の区画に収納する。またスライド部材８３の脚片８３ａを挿通孔を介して第１側ケース１Ａの側壁の外側面に形成せるスライド溝２０７に入れて突出部２０６を外部に露出させる。
【００７４】
さらに、内方収納部２００に沿って第１側ケース１Ａの高さ方向に形成された分離壁９１と、第１側ケース１Ａの長手方向略中央で分離壁９１に対向して高さ方向に形成された分離壁６５との間の空間上部に、長手方向の寸法が長い第２の回路基板７４を隔壁９１側として零相変流器ＺＣＴに取り付けた第１及び第２の回路基板７３，７４を収納するとともに、上記空間下部に第１及び第３の電磁釈放装置４７Ｂ，４８を収納する。ここで、第１側ケース１Ａ底部の隔壁９１近傍の部位には器体１の幅方向に沿って２条のリブ９２が設けてあり、この２条のリブ９２間に形成される嵌合溝９２ａに第２の回路基板７４の下端部を嵌合することにより、その長手方向が第１側ケース１Ａの高さ方向と略一致し且つ零相変流器ＺＣＴの軸方向が第１側ケース１Ａの長手方向と略一致するように第２の回路基板７４を位置決め固定している。
【００７５】
また、両側ケース１Ａ，１Ｂの零相変流器ＺＣＴと対向する側壁に矩形の窓孔９８をそれぞれ開口し、ハウジング７５の幅寸法が最も大きい部分を窓孔９８に挿入してハウジング７５の逃げとしている。すなわち、零相変流器ＺＣＴのハウジング７５の幅寸法が第１及び第２の回路基板７３，７４の幅寸法よりも若干大きいために器体１の幅寸法をハウジング７５の幅寸法に合わせると無駄なスペースが生じてしまうが、上述のように窓孔９８を設けてハウジング７５を逃がすことにより、無駄なスペースが生じるのを防いで器体１の幅寸法の小型化が図れる。但し、窓孔９８に挿入したハウジング７５が両側ケース１Ａ，１Ｂの側壁外側面よりも突出しないようにハウジング７５並びに器体１の幅寸法を設定している。
【００７６】
一方、第２及び第３の電磁釈放装置４７Ｂ，４８は、図１１に示すように可動鉄心５８を器体１の高さ方向において下にして上記空間下部の第１側ケース１Ａ底部に配置され、器体１の高さ方向における固定鉄心５７の上部に零相変流器ＺＣＴが配置されている。このように板ばね５９で連結した固定鉄心５７及び可動鉄心５８を器体１の高さ方向にそって器体１底部に配置するとともに、固定鉄心５７及び可動鉄心５８の上部に、軸方向を器体１の長手方向に略一致させて零相変流器ＺＣＴを配置すれば、固定鉄心５７及び可動鉄心５８に挟まれる通電導体８０をその延出方向を器体１の長手方向に一致させて器体１内に配設することができるために器体１の高さ方向の寸法を小型化することができる。また、固定鉄心５７及び可動鉄心５８の高さ方向上部に零相変流器ＺＣＴを配置することで器体１の長手方向の寸法を小型化することができる。さらに、零相変流器ＺＣＴの軸方向を器体１の長手方向と一致させているから、主回路の電路（編組線７９Ａ，７９Ｂ）を零相変流器ＺＣＴに貫通させる作業が容易に行える。あるいは、予め編組線７９Ａ，７９Ｂを零相変流器ＺＣＴに貫通させた状態で第１側ケース１Ａに組み込む場合には、器体１内で編組線７９Ａ，７９Ｂを引き回す距離が短くて済む。しかも、可動鉄心５８を器体１の底部側に配置しているため、可動鉄心５８の吸引動作に零相変流器ＺＣＴの影響が及ばず、後述する主接点の開極特性を安定させることができる。
【００７７】
ここで、外片８０ｂの先端部に後端部が連結された可動接触子４Ｂは、その中央部の斜め上向きの傾斜部位を、第１側ケース１Ａの底部よりやや上方に位置する分離壁６５の下端より第１側ケース１Ａの他端部方向へ底部に平行し、さらにこの平行部より上向きに傾斜して延長された隔壁９５と第１側ケース１Ａの底部との間に配置して、可動接触子４Ｂの自由端側を隔壁１４の切欠部１４ａを介して固定接触子１２Ｂが配置される空間に配設される。このとき隔壁９５の平行部の下面と第１側ケース１Ａの底部とにそれぞれ突設した複数のリブ９６で可動接触子４Ｂの後端部を挟んで固定する。またこのとき第１側ケース１Ａの底部と可動接触子４Ｂとの間に、第１の回路基板７３とリード線８２Ｂで接続された接続部材９９を挟持固定して漏電保護回路５１並びに試験回路７０を片方の極の電路に接続している。
【００７８】
さらに分離壁６５と隔壁９５との間の空間に、導電板７１Ａ，７１Ｂ並びにバイメタル４５，４６を保持させた隔壁部材３１を収納する。このとき隔壁部材３１の下部周壁３１ｂの斜め上向きに傾斜した傾斜部位を隔壁９５の傾斜部位に沿うように載置することにより、隔壁部材３１を器体１の上記空間内で位置決めしている。而して、器体１の長手方向においてバイメタル４５，４６に近い側に第１の回路基板７３が配置されることになるため、第２の回路基板７４とバイメタル４５，４６との距離を離して第２の回路基板７４に実装したＩＣ（漏洩電流判定回路５１ａ）等の熱に弱い弱電系の回路部品にバイメタル４５，４６の発する熱の影響が及ぶのを抑えることができる。
【００７９】
さらにまた第２鉄心６０を復帰ばね６４とともに凹所３１ｃ内に配置した後に第１引外し板４１をねじりばね８１とともに定位置に回動自在に配置するとともに、第２引外し板４２を定位置に回動自在に配置する。このとき第２引外し板４２の受け部４２ｃが可動鉄心５８の先端部と対向する。
【００８０】
このようにして図１１に示すように中間ケース７及びこの中間ケース７の凹部９内に収納する端子ブロック１０Ｂ、解除ハンドル１７’及びその復帰ばね２１’以外を第１側ケース１Ａ側に配置、組み付けた後に、端子ブロック１０Ｂ、解除ハンドル１７’及び復帰ばね２１’を凹部９に組み付けた中間ケース７を第１側ケース１Ａ側に重ねるように配設する。
【００８１】
ここで中間ケース７を第１側ケース１Ａ側の定位置に配設すると、可動接触子４Ａの自由端側が縦壁の開口部を介して凹所内に配置されるとともに、端子ブロック１０Ａに設けられた固定接触子１２Ａの先端側部が底壁の段面上に載置されることになるとともに軸が解除ハンドル１７の凹部３７に嵌まることになる。
【００８２】
一方端子ブロック１０Ｂに設けられた固定接触子１２Ｂが第１側ケース１Ａの底部上のリブ２６上に載置される。また中間ケース７の端部に形成せる下向き段部の下面が第１側ケース１Ａの端部壁に形成した平坦面上に載置される。
【００８３】
この状態で第２側ケース１Ｂを第１側ケース１Ａ側に重ね合わせて結合するのである。このとき第１側ケース１Ａから第２側ケース１Ｂ側へ一体突出させた両端上下の４カ所の弾性係止片１００の先端の爪状の引掛係止部１０１が第２側ケース１Ｂ側に対応して設けた突起状の被引掛部１０２に係止されて第１側ケース１Ａと第２側ケース１Ｂとが結合固定されて器体１を構成することになる（図１１等参照）。この第１側ケース１Ａと第２側ケース１Ｂの結合固定を外す場合には、第２側ケース１Ｂに各被引掛部１０２に対応させて開口した各解除孔１５０よりドライバを挿入して対応する各弾性係止片１００の引掛係止部１０１を上方へ押圧して、被引掛部１０２との引掛状態を外すことにより、第１側ケース１Ａから第２側ケース１Ｂを外すことができる。
【００８４】
第２側ケース１Ｂを被着することにより第２側ケース１Ｂの内側面に設けてある軸孔５２，５６にクロスバー４０の軸４０ａ、第１引外し板４１の軸部４１ａが回動自在に挿入される。
【００８５】
また各バイメタル４５，４６に対応する調整螺子７７，７７’の頭部は、隔壁部材３１の切り欠き３１ｅを通して器体１の上面に開口する開口部１０４に臨むことになり、組立後の動作試験時に最適な動作点が得られるように開口部１０４を介して動作調整螺子７７，７７’を螺進させ、バイメタル４５の先端部とクロスバー４０の脚部４１ｃ並びにバイメタル４６の先端部と第２引外し板４２の駆動片４２ｄとの間隔を調整し、その調整後に、蓋１０６をその弾性を利用して器体１の開口部１０４周縁の部位に嵌め込んで開口部１０４を被蔽する。
【００８６】
ここでバイメタル４５，４６は、隔壁部材３１に保持された状態で器体１の幅方向を幅方向として並設され、器体１の幅方向の寸法の小型化を図っている。また変位方向を互いに器体１の長手方向に沿って第２の回路基板７４及び第１及び第３の電磁釈放装置４７Ｂ，４８から遠ざかる向きに設定しているため、バイメタル４５，４６と第１及び第３の電磁釈放装置４７Ｂ，４８並びに零相変流器ＺＣＴ（第２の回路基板７４）との間隔を狭くして器体１の長手方向の小型化が図れる。
【００８７】
またバイメタル４５，４６の間を隔壁部材３１の隔壁３１ａで隔絶するため、隔壁３１ａによって両バイメタル４５，４６間の絶縁を図るとともにその間隔を狭くすることができる。さらに零相変流器ＺＣＴを器体１の幅方向に隔壁３１ａを跨ぐように配置することにより、各バイメタル４５，４６に接続される編組線７９Ａ，７９Ｂを零相変流器ＺＣＴに貫通させ易くしている。またさらに固定鉄心５７及び可動鉄心５８を含む第１及び第３の電磁釈放装置４７Ｂ，４８も器体１の幅方向に隔壁３１ａを跨ぐように配置しているから、固定鉄心５７並びに可動鉄心５８の幅寸法を充分に大きくすることができ、電磁吸引力を増大させて主接点の開極に要する時間を短くすることができる。
【００８８】
而して器体１の他端内部の内方収納部２００及び収納部９０には選択端子Ｔ２、固定端子Ｔ１がそれぞれ収納され、またこれら端子Ｔ１，Ｔ２に対応するように器体１の一端部には器体１の端面と両側面とに亘るように開口した差込部２０９ａ〜２０９ｃが形成されることになる。さらに器体１の一端部には斜め上向きに開口した一対の電線挿入孔１６Ａ，１６Ｂが並行形成される。
【００８９】
よって、電線挿入孔１６Ａ，１６Ｂにそれぞれ負荷側の電線を挿入して各端子ブロック１０Ａ，１０Ｂに接続し、電圧極の導電バーを差込部２０９ｃを介して幅方向に固定端子Ｔ１に差込接続し、中性極又は他方の電圧極の導電バーを差込部２０９ａ又は２０９ｂを介して選択端子Ｔ２に幅方向に差込接続すれば電路に本実施形態の漏電遮断器を挿入することができることになる。
【００９０】
ところで、図１に示すように第２側ケース１Ｂの開口部１０４近傍にはテスト釦７８を挿通する挿通孔１０５ａが貫通した突台部１０５が設けてあり、先端を二股に形成したテスト釦７８を上方から挿通孔１０５ａに挿通して係止段部７８ａを器体１内の挿通孔１０５ａ周縁に係止することでテスト釦７８が器体１の高さ方向に移動自在且つ抜け止めして突台部１０５に取り付けられる。このテスト釦７８の先端部が第２の回路基板７４に実装したテストスイッチＳＷの可動接点板７６ａと対向しており、テスト釦７８を押操作することでその先端部にて可動接点板７６ａを押駆動して固定接点７６ｂに接触させ、テストスイッチＳＷをオンさせることができる。なお、蓋１０６にはテスト釦７８との干渉を避けるためにテスト釦７８が挿通する半円形の切り欠き１０６ａが設けてある。
【００９１】
ここで、器体１両側面には零相変流器ＺＣＴのハウジング７５が部分的に露出する窓孔９８が開口しているので、窓孔９８から器体１内への異物侵入を防止するとともに外観上の見栄えを良くするために、絶縁性を有するシート状の材料で角筒状に形成された絶縁シート（図示せず）を器体１に取着して窓孔９８を覆い隠している。
【００９２】
次に本実施形態の動作を図２，図３並びに図１２〜図１５を参照して説明する。図３は開放状態を示しており、この開放状態ではハンドル６の操作部６ａが窓孔５０より倒立露出した状態にあり、作動板４３の一端と第１引外し板４１との係合は外れた状態にある。そしてコイルばね６２によりクロスバー４０は図３においては反時計回りに回動するように付勢されており、クロスバー４０の切溝５４に貫挿されている可動接触子４Ａが自由端を上方に移動させた状態にあり、また切溝５５に貫挿させた可動接触子４Ｂはそのばね弾性力により自由端を上方に移動させた状態にあり、夫々の自由端に設けてある可動接点３Ａ，３Ｂが対応する固定接点２Ａ，２Ｂから開離した状態にある。
【００９３】
この状態でハンドル６の操作部６ａを図３における反時計回りに回動操作すると、リンク４４の上側軸４４ａが下方向に押し動かされてリンク４４は下側軸４４ｂにより作動板４３を押し下げる。この作動板４３の押し下げにより作動板４３の一端（図３において左端）が第１引外し板４１の係止部４１ｅに当たり、その位置を回動中心として作動板４３は図３において時計回りに回動し、作動板４３の他端（図３において右端）がクロスバー４０の上端に設けてある突出部８４に当たり、クロスバー４０を図３において時計回りにばね付勢に抗して回動させる。
【００９４】
この回動によりクロスバー４０の切溝５５に貫挿された可動接触子４Ｂが自由端を下向きに移動させる方向に撓むことになり、自由端の可動接点３Ｂを固定接点２Ｂに接触させる。また切溝５４に貫挿された可動接触子４Ａが図３において時計回りに回動してその自由端の可動接点３Ａを固定接点２Ａに接触させる。この接触は可動接点３Ｂが固定接点２Ｂに接触するよりも遅れるようなっている。
【００９５】
そしてハンドル６をさらに回動させると、リンク４４の下側軸４４ｂの位置とハンドル６の回転中心を結ぶ線より上側軸４４ａが図２に示すように右方向に移動し、この状態でハンドル６のねじりばね３６、クロスバー４４を付勢するコイルスばね６２、更に可動接触子４Ｂのばね力等が均衡して作動板４３の一端と第１引外し板４１の係止部４１ｅとのラッチ状態が保持され、図２の投入状態が維持される。
【００９６】
さて投入状態でハンドル６の操作部６ａを図２において時計回りに回動させると、リンク４４の上側軸４４ａの位置が、ハンドル６の回転中心と、下側軸４４ｂを結ぶ線を図２において左方向に越えて上方へ移動するため作動板４３の図２における左端と第１引外し板４１の係止部４１ｅとのラッチ状態が解かれ、クロスバー４０はコイルばね６２の付勢力で図２において反時計回りに回動するとともに、ハンドル６がねじりばね３６の付勢力でオフ側に急速に回動復帰する。クロスバー４０の図２における反時計回りへの回動により可動接触子４Ａが図２における反時計回りに回動して自由端を上方へ移動させ可動接点３Ａを固定接点２Ａより開離させる。また可動接触子４Ｂが下向きの押し下げが無くなって、そのばね力で元の状態に復帰することになり、自由端の可動接点３Ｂを固定接点２Ｂより開離する。この開離は上記可動接点３Ａが固定接点２Ａから開離するよりも遅れる。この遅れは後述する強制開極時も同様である。
【００９７】
ここで上記のように両極の主接点の開閉に上記のように遅れを持たせているため接点開閉時に生じるアークは剛体側の可動接触子４Ａのみとなり、ばね材からなる可動接触子３Ｂのアークによる消耗を防止できる。
【００９８】
さらに主接点の開離時に回動するクロスバー４０の先端面の幅方向に形成した凹溝１３１に両ケース１Ａ，１Ｂ及び中間ケース７に形成した止片１３０…が係入して凹溝１３１の底部に当接するため、一方の区画で発生したアークが器体１の奥側のクロスバー４０側から回りこんで他の区画へ入り込む恐れを無くして、器体１内部でのアークによる極間短絡を防止する。
【００９９】
さて図２に示す上記投入状態において、負荷に過電流が流れると、バイメタル４５，４６は過電流により発熱して湾曲変位することになる。ここで上方から垂下したバイメタル４５，４６は下端が図２において右方向に移動するように変位し、バイメタル４６の下端は第２引外し板４２の駆動片４２ｄを図２における右方向に押し、バイメタル４５の下端は第１引外し板４１の脚部４１ｃ先端の受け部４１ｇを図２における右方向に押す。そしてバイメタル４６の変位によって第２引外し板４２が図２における時計回りに回動し、第２引外し板４２の対向部４２ａが第１引外し板４１の受け部４１ｆを右方向に押す。そして、第１引外し板４１は受け部４１ｇがバイメタル４５に押されるとともに受け部４１ｆが第２引外し板４２に押されることで図２において反時計回りに回動する。
【０１００】
さて第１引外し板４１が図２において反時計回りに回動すると、係止部４１ｅと作動板４３の一端（図２における左端）とのラッチ状態が解除され、作動板４３はリンク４４の下側軸４４ｂを中心として図２において反時計回りに回動することになる。そのため作動板４３の他端（図２における右端）によるクロスバー４０の規制が無くなり、クロスバー４０はコイルばね６２のばね力により図２において反時計回りに回動し、可動接触子４Ａ，４Ｂを開放状態に復帰させ、可動接点３Ａ，３Ｂを固定接点２Ａ，２Ｂからそれぞれ開離させる。すなわち、主回路に過負荷電流が流れた場合には、熱動釈放装置によって開閉機構５が釈放されて主接点を強制的に開極して負荷を保護することができる。
【０１０１】
その後、電路遮断によりバイメタル４５，４６は元の状態に戻り、第１引外し板４１はねじりばね８１の付勢により元の位置へ回動復帰し、同時に第２引外し板４２の対向部４２ａを受け部４１ｆが押し動かして第２引外し板４２を元へ戻す。またハンドル６はねじりばね３６の付勢により開放方向（図２における時計回り）に回動することになる。
【０１０２】
また上記投入状態において、短絡電流（回路短絡による大きな短絡電流）のような異常な大電流が一方の極の通電導体８０に流れると、固定鉄心５７に電磁吸引力が発生して可動鉄心５８を吸引して揺動させる。これにより図１２に示すように、可動鉄心５８の先端部が第２引外し板４２の受け部４２ｃを押し上げて第２引外し板４２を反時計回りに回動させる。過負荷電流が流れたときと同様に第２引外し板４２が反時計回りに回動すると、第２引外し板４２の対向部４２ａが第１引外し板４１の受け部４１ｆを左方向に押して時計回りに回動する。そして、第１引外し板４１が時計回りに回動すると、係止部４１ｅと作動板４３の一端（右端）とのラッチ状態が解除され、作動板４３はリンク４４の下側軸４４ｂを中心として時計回りに回動することになる。そのため作動板４３の他端（左端）によるクロスバー４０の規制が無くなり、クロスバー４０はコイルばね６２のばね力により時計回りに回動し、可動接触子４Ａ，４Ｂを開放状態に復帰させ、可動接点３Ａ，３Ｂを固定接点２Ａ，２Ｂからそれぞれ開離させる。すなわち、主回路の一方の極（固定接点２Ｂ及び可動接点３Ｂ）に短絡電流のような異常な大電流が流れた場合には、第２の電磁釈放装置４７Ｂによって開閉機構５が釈放されて主接点を強制的に開極することができる。
【０１０３】
その後、電路遮断により固定鉄心５７に電磁吸引力が発生しなくなると、可動鉄心５８は板ばね５９のばね力により元の状態に戻り、第１引外し板４１はねじりばね８１の付勢により元の位置へ回動復帰し、同時に第２引外し板４２の対向部４２ａを受け部４１ｆが押し動かして第２引外し板４２を元へ戻す。またハンドル６はねじりばね３６の付勢により開放方向（反時計回り）に回動することになる。なお、第２の電磁釈放装置４７Ｂの動作電流はコード短絡電流よりも大きい値に設定されており、上述のように回路短絡による短絡電流（同図における実線ハ参照）では動作するが、コード短絡電流（同図における実線ロ参照）では動作しないようになっている。
【０１０４】
さらに上記投入状態において、地絡電流等の漏洩電流が流れると、漏電保護回路５１がコイル６８に通電することにより固定鉄心５７に電磁吸引力が発生して可動鉄心５８を吸引して揺動させる。これにより短絡電流が流れたときと同様、図１２に示すように、可動鉄心５８の先端部が第２引外し板４２の受け部４２ｃを押して第２引外し板４２を反時計回りに回動させるとともに第１引外し板４１を時計回りに回動させ、可動接触子４Ａ，４Ｂを開放状態に復帰させて可動接点３Ａ，３Ｂを固定接点２Ａ，２Ｂからそれぞれ開離させる。すなわち、主回路に漏洩電流が流れた場合には、第３の電磁釈放装置４８によって開閉機構５が釈放されて主接点を強制的に開極して地絡保護ができる。
【０１０５】
一方上記投入状態において、コード短絡電流や短絡電流が他方の極のバイメタル４５に流れると、第１の電磁釈放装置４７Ａによって開閉機構５が釈放されて主接点を強制的に開極する。すなわち、第１の電磁釈放装置４７Ａの動作電流は越流（図１５（ａ）における実線イ参照）よりも大きく且つコード短絡電流よりも小さい値に設定されており（同図（ａ）のレベルＢ）、短絡電流に比較してレベルの小さいコード短絡電流でも動作するようになっている。
【０１０６】
而して、通電導体であるバイメタル４５にコード短絡電流又は短絡電流が流れると、第２鉄心６０の側片６０ｂの磁極面と第１鉄心６１との間に発生する電磁吸引力により、まず第２鉄心６０が復帰ばね６４のばね力に抗して第１鉄心６１に近付く向きに移動し、側片６０ａが凹溝３１ｈの端面に当接する位置まで第２鉄心６０が移動した後にさらに電磁吸引力により第１鉄心６１が第２鉄心６０に近付く向きに吸引揺動させる。これにより図１３に示すように、第１鉄心６１が取着されている第１引外し板４１が図１３における反時計回りに回動し、係止部４１ｅと作動板４３の一端（左端）とのラッチ状態が解除され、作動板４３はリンク４４の下側軸４４ｂを中心として反時計回りに回動することになる。そのため作動板４３の他端（右端）によるクロスバー４０の規制が無くなり、クロスバー４０はコイルばね６２のばね力により反時計回りに回動し、可動接触子４Ａ，４Ｂを開放状態に復帰させ、可動接点３Ａ，３Ｂを固定接点２Ａ，２Ｂからそれぞれ開離させる。
【０１０７】
図１５はバイメタル４５に越流（同図（ａ）の実線イ）、コード短絡電流（同図（ａ）の実線ロ）、短絡電流（同図（ａ）の実線ハ）、並びにモータやインバータのような負荷を起動したときに越流よりも遙かに短い時間で瞬時に流れる突入電流（同図（ａ）の実線ニで表し、以下「瞬時突入電流」と呼ぶ）が流れた場合の第１鉄心６１と第２鉄心６０の移動する様子を表している。また、第２鉄心６０が復帰ばね６４のばね力に抗して移動を開始するときの電流の閾値を同図（ａ）においてはレベルＣとしている。ここで、図１５（ｂ）〜（ｅ）における横軸は上述のような定格を超える電流が流れ始めた時点からの経過時間〔秒〕を示し、縦軸は第１鉄心６１と第２鉄心６０の位置を示している。但し、定格以下の電流しか流れていないときの第１鉄心６１及び第２鉄心６０のそれぞれの位置（初期位置）は、第１鉄心６１についてはＰ１、第２鉄心６０については縦軸のゼロの位置とし、第２鉄心６０が移動して第１鉄心６１に最も近付いたときの位置（移動完了位置）をＰ２とする。また、図１６は第１鉄心６１と第２鉄心６０の間にはたらく電磁吸引力（動作時荷重）〔Ｎ〕と両者の距離〔ｍｍ〕との関係を示しており、電磁吸引力が閾値Ｘ１を超えると復帰ばね６４のばね力に電磁吸引力が勝って第２鉄心６０が第１鉄心６１に近付く向きに移動し始め、電磁吸引力が閾値Ｘ２に達した時点で第２鉄心６０が移動完了位置Ｐ２に至る。そこからさらに電磁吸引力が増大して閾値Ｘ３を超えると、ねじりばね８１のばね力とラッチ状態にある作動板４３が第１引外し板４１に与える荷重の和に電磁吸引力が勝って、今度は第１鉄心６１が第２鉄心６０に近付く向きに移動し始め、電磁吸引力が閾値Ｘ４に達した時点で第１引外し板４１の係止部４１ｅと作動板４３の一端とのラッチ状態が解除されて引外し動作が行われる。なお、第１の電磁釈放装置４７Ａの動作電流（レベルＢ）は第２鉄心６０が移動完了位置にあるときの第１鉄心６１との距離に基づいた値（閾値Ｘ４の電磁吸引力を生じる電流値）となっている。また、図１５（ａ）におけるレベルＡは第２鉄心６０が復帰ばね６４のばね力に抗して移動を開始する電流レベルであり、レベルＤは第２鉄心６０が初期位置にあるときの動作電流を示している。
【０１０８】
而して、バイメタル４５に越流が流れた場合、図１５（ｃ）に示すように越流がレベルＣを超えた時点から第２鉄心６０が初期位置から移動を開始して移動完了位置Ｐ２まで移動するものの、越流がレベルＡを超えないために第１鉄心６１は移動を開始せずに初期位置Ｐ１に留まっているから、越流が流れても主接点が強制開極されることはない。
【０１０９】
一方、バイメタル４５にコード短絡電流が流れた場合、図１５（ｄ）に示すようにコード短絡電流がレベルＣを超えた時点から第２鉄心６０が初期位置から移動を開始して移動完了位置Ｐ２まで移動し、その後、コード短絡電流がレベルＡを超えた時点から第１鉄心６１が初期位置Ｐ１から移動を開始して第２鉄心６０に近づき、コード短絡電流がレベルＢを超えて第２鉄心６０と第１鉄心６１との距離が所定値以下となったときに第１引外し板４１の係止部４１ｅと作動板４３の一端とのラッチ状態が解除されて引外し動作が行われて主接点（固定接点２Ａと可動接点３Ａ）が強制開極される。また、図１５（ｅ）に示すようにバイメタル４５に短絡電流が流れた場合もコード短絡電流が流れた場合と同様であるが、短絡電流の立ち上がり時間がコード短絡電流の立ち上がり時間よりも短いため、電流が流れ始めてから動作電流（レベルＡ）に達するまでの時間も短くなって引外し動作の開始も早まることになる。
【０１１０】
しかしながら、図１５（ａ）の実線ニに示すような瞬時突入電流がバイメタル４５に流れた場合には、同図（ｂ）に示すように瞬時突入電流が非常に短い時間しか流れないので、移動を開始した第２鉄心６０が移動完了位置Ｐ２に達する前に瞬時突入電流が流れなくなる。そのために第１鉄心６１と第２鉄心６０との距離が所定値を下回ることがなく、主接点が誤って強制開極されることを防止できるものである（図１４参照）。
【０１１１】
（実施形態２）
本実施形態は、第２鉄心６０と器体１との間に第２鉄心６０を第１鉄心６１から離す向きに弾性付勢する復帰ばね６４を介装した点に特徴があり、これ以外の構成は実施形態１と共通である。よって、実施形態１と共通の構成要素には同一の符号を付して説明を省略し、本実施形態の特徴となる構成についてのみ説明する。
【０１１２】
図１７に示すように第２鉄心６０の短い方の側片６０ａの先端面に円柱形のばね座６０ｃが突設されるとともに、側片６０ａの先端面と対向する凹溝３１ｈの片側（図１７における右側）の端面にも円柱形のばね座３１ｉが突設されており、これら２つのばね座６０ｃ，３１ｉに復帰ばね６４の両端部がそれぞれ外挿されて第２鉄心６０と器体１（隔壁部材３１）との間に復帰ばね６４が介装されている。
【０１１３】
而して、バイメタル４５に定格を超える電流が流れていなければ、図１８（ａ）に示すように第２鉄心６０は復帰ばね６４のばね力で第１鉄心６１から離れる向きに付勢されて隔壁部材３１の周壁３１ｂに当接した状態で保持されている。そして、バイメタル４５に流れる電流が上記レベルＣを超えると、同図（ｂ）に示すように復帰ばね６４のばね力に抗して第２鉄心６０が第１鉄心６１に近付く向きに移動し始め、復帰ばね６４の圧縮限界において第２鉄心６０の移動が停止する。バイメタル４５に流れる電流がさらに大きくなって上記レベルＡを超えれば、第１鉄心６１が第２鉄心６０に近付く向きに移動を開始し、上記レベルＢを超えた時点で同図（ｃ）に示すように第１鉄心６１と第２鉄心６０との距離が所定値以下となったときに第１引外し板４１の係止部４１ｅと作動板４３の一端とのラッチ状態が解除されて引外し動作が行われて主接点（固定接点２Ａと可動接点３Ａ）が強制開極される。
【０１１４】
上述のように本実施形態では、第２鉄心６０と器体１との間に第２鉄心６０を第１鉄心６１から離す向きに弾性付勢する復帰ばね６４を介装したので、第２鉄心６０と復帰ばね６４を隔壁部材３１に配設した後にバイメタル４５や第１鉄心６１を配設することができて組立作業が容易になるものである。
【０１１５】
（実施形態３）
本実施形態は、実施形態１，２における第２鉄心６０を隔壁部材３１に対して移動しないように固定した固定鉄心とし、第１鉄心（可動鉄心）６１を第１引外し板４１に対して固定鉄心６０と接離する方向に移動自在に設けるとともに、第１引外し板４１を作動板４３の動きを規制する方向に付勢する力（ねじりばね８１のばね力）よりも弱い力で可動鉄心６１を固定鉄心６０から離れる向きに付勢するようにした点に特徴がある。このように第１の電磁釈放装置４７Ａ以外の構成は実施形態１又は２と共通であるから、共通の構成要素には同一の符号を付して説明を省略する。
【０１１６】
本実施形態における第１の電磁釈放装置４７Ａは、棒状の主部６６ａの先端に鍔部６６ｂを設けた一対の取付部材６６を具備し、可動鉄心６１を表裏に貫通し主部６６ａの径よりも大きく且つ鍔部６６ｂの径よりも小さい径を有する一対の貫通孔６１ａに各々取付部材６６の主部６６ａを挿通するとともに貫通孔６１ａに挿通した主部６６ａの後端を、第１引外し板４１の突出部４１ｂの上端部における係止部４１ｅと反対側の面に形成される一対の圧入孔４１ｉに圧入することで固定し、圧縮コイルばねからなる復帰ばね６４を取付部材６６の主部６６ａに挿通して鍔部６６ｂと可動鉄心６１との間に配置して構成される。すなわち、可動鉄心６１は取付部材６６により第１引外し板４１に対して固定鉄心６０に接離する方向で移動自在に取り付けられており、復帰ばね６４のばね力によって固定鉄心６０から離れる向きに弾性付勢されている。なお、復帰ばね６４のばね力は第１引外し板４１を作動板４３の動きを規制する方向に付勢するねじりばね８１のばね力よりも弱く設定される。
【０１１７】
而して、バイメタル４５にコード短絡電流や短絡電流が流れたときに固定鉄心６０の側片６０ｂの磁極面と可動鉄心６１との間に発生する電磁吸引力により、まず可動鉄心６１が復帰ばね６４のばね力に抗して取付部材６６の鍔部６６ｂに近付く向きに移動し、復帰ばね６４の圧縮限界まで移動した後、さらに電磁吸引力によりねじりばね８１のばね力に抗して可動鉄心６１を固定鉄心６０に近付く向きに吸引揺動させ、可動鉄心６１が取着された第１引外し板４１を、図２０における反時計回りに回動させるのである。
【０１１８】
次に本実施形態の動作を図２０〜図２６を参照して説明する。但し、投入状態から開放状態又は開放状態から投入状態へ手動で切り換える場合の動作、並びに第２及び第３の電磁釈放装置４７Ｂ、４８と熱動釈放装置によって主接点を強制開極させる場合の動作については実施形態１と共通であるから説明を省略し、本実施形態の特徴である第１の電磁釈放装置４７Ａにより主接点を強制開極される場合の動作についてのみ説明する。
【０１１９】
図２０に示す投入状態において、コード短絡電流や短絡電流がバイメタル４５に流れると、第１の電磁釈放装置４７Ａによって開閉機構５が釈放されて主接点を強制的に開極する。すなわち、実施形態１と同様に第１の電磁釈放装置４７Ａの動作電流は越流（図２５（ａ）における実線イ参照）よりも大きく且つコード短絡電流よりも小さい値に設定されており（同図（ａ）のレベルＢ）、短絡電流に比較してレベルの小さいコード短絡電流でも動作するようになっている。
【０１２０】
而して、バイメタル４５にコード短絡電流又は短絡電流が流れると、固定鉄心６０の側片６０ｂの磁極面と可動鉄心６１との間に発生する電磁吸引力により、まず可動鉄心６１が復帰ばね６４のばね力に抗して取付部材６６の鍔部６６ｂに近付く向きに移動し、復帰ばね６４の圧縮限界まで移動した後、さらに電磁吸引力によりねじりばね８１のばね力に抗して可動鉄心６１を固定鉄心６０に近付く向きに吸引揺動させる。これにより図２３に示すように、可動鉄心６１が取着されている第１引外し板４１が図２３における反時計回りに回動し、係止部４１ｅと作動板４３の一端（左端）とのラッチ状態が解除され、作動板４３はリンク４４の下側軸４４ｂを中心として反時計回りに回動することになる。そのため作動板４３の他端（右端）によるクロスバー４０の規制が無くなり、クロスバー４０はコイルばね６２のばね力により反時計回りに回動し、可動接触子４Ａ，４Ｂを開放状態に復帰させ、可動接点３Ａ，３Ｂを固定接点２Ａ，２Ｂからそれぞれ開離させる。
【０１２１】
図２５はバイメタル４５に越流（同図（ａ）の実線イ）、コード短絡電流（同図（ａ）の実線ロ）、短絡電流（同図（ａ）の実線ハ）、並びに瞬時突入電流（同図（ａ）の実線ニ）が流れた場合の可動鉄心６１と固定鉄心６０の移動する様子を表している。また、可動鉄心６１が復帰ばね６４のばね力に抗して第１引外し板４１に対して移動を開始するときの電流の閾値を同図（ａ）においてはレベルＣとしている。ここで、図２５（ｂ）〜（ｅ）における横軸は上述のような定格を超える電流が流れ始めた時点からの経過時間〔秒〕を示し、縦軸は可動鉄心６１と固定鉄心６０の位置を示している。但し、固定鉄心６０の位置Ｐ３、定格以下の電流しか流れていないときの可動鉄心６１の位置（初期位置）を縦軸のゼロの位置とし、可動鉄心６１が第１引外し板４１に対して移動して取付部材６６の鍔部６６ｂに最も近付いたときの位置（移動完了位置）をＰ４とする。また、図２６は可動鉄心６１と固定鉄心６０の間にはたらく電磁吸引力〔Ｎ〕と両者の距離〔ｍｍ〕との関係を示しており、電磁吸引力が閾値Ｙ１を超えると復帰ばね６４のばね力に電磁吸引力が勝って可動鉄心６１が第１引外し板４１に対して鍔部６６ｂに近付く向きに移動し始め、電磁吸引力が閾値Ｙ２に達した時点で可動鉄心６１が移動完了位置Ｐ４に至る。そこからさらに電磁吸引力が増大して閾値Ｙ３を超えると、ねじりばね８１のばね力とラッチ状態にある作動板４３が第１引外し板４１に与える荷重の和に電磁吸引力が勝って、可動鉄心６１が固定鉄心６０に近付く向きに移動し始め、電磁吸引力が閾値Ｙ４に達した時点で第１引外し板４１の係止部４１ｅと作動板４３の一端とのラッチ状態が解除されて引外し動作が行われる。なお、第１の電磁釈放装置４７Ａの動作電流（レベルＢ）は可動鉄心６１が移動完了位置Ｐ４にあるときの固定鉄心６０との距離に基づいた値（閾値Ｙ４の電磁吸引力を生じる電流値）となっている。また、図２５（ａ）におけるレベルＡは可動鉄心６１が復帰ばね６４のばね力に抗して移動を開始する電流レベルであり、レベルＤは可動鉄心６１が初期位置にあるときの動作電流を示している。
【０１２２】
而して、バイメタル４５に越流が流れた場合、図２５（ｃ）に示すように越流がレベルＣを超えた時点から可動鉄心６１が初期位置から移動を開始して移動完了位置Ｐ３まで移動するものの、越流がレベルＡを超えないために可動鉄心６１は移動完了位置Ｐ３からさらに固定鉄心６０に近付く向きに移動しないから、越流が流れても主接点が強制開極されることはない。
【０１２３】
一方、バイメタル４５にコード短絡電流が流れた場合、図２５（ｄ）に示すようにコード短絡電流がレベルＣを超えた時点から可動鉄心６１が初期位置から移動を開始して移動完了位置Ｐ３まで移動し、その後さらに、コード短絡電流がレベルＡを超えた時点から可動鉄心６１が移動完了位置Ｐ３からさらに固定鉄心６０に近付く向きに移動し、コード短絡電流がレベルＢを超えて固定鉄心６０と可動鉄心６１との距離が所定値以下となったときに第１引外し板４１の係止部４１ｅと作動板４３の一端とのラッチ状態が解除されて引外し動作が行われて主接点（固定接点２Ａと可動接点３Ａ）が強制開極される。また、図２５（ｅ）に示すようにバイメタル４５に短絡電流が流れた場合もコード短絡電流が流れた場合と同様であるが、短絡電流の立ち上がり時間がコード短絡電流の立ち上がり時間よりも短いため、電流が流れ始めてから動作電流（レベルＡ）に達するまでの時間も短くなって引外し動作の開始も早まることになる。
【０１２４】
しかしながら、図２５（ａ）の実線ニに示すような瞬時突入電流がバイメタル４５に流れた場合には、同図（ｂ）に示すように瞬時突入電流が非常に短い時間しか流れないので、移動を開始した可動鉄心６１が移動完了位置Ｐ４に達する前に瞬時突入電流が流れなくなる。そのために可動鉄心６１と固定鉄心６０との距離が所定値を下回ることがなく、主接点が誤って強制開極されることを防止できるものである（図２４参照）。
【０１２５】
ここで本実施形態における第１の電磁釈放装置４７Ａでは、取付部材６６の主部６６ａに外挿した復帰ばね６４を鍔部６６ｂと可動鉄心６１との間に配置しているので、復帰ばね６４が鍔部６６ｂと可動鉄心６１との間で取付部材６６の主部６６ａに支持されることとなり、復帰ばね６４の脱落や座屈が防止できる。また、複数の取付部材６６を第１の電磁釈放装置４７Ａに具備するとともに、各取付部材６６の主部６６ａを挿通する複数の貫通孔６１ａを可動鉄心６１に設けているので、第１引外し板４１の揺動部位（突出部４１ｂ）に対する可動鉄心６１の位置ずれを防止して特性を安定化させることができる。さらに取付部材６６の主部６６ａの後端を挿抜自在に圧入する圧入孔４１ｉを第１引外し板４１の揺動部位に設けているので、復帰ばね６４や可動鉄心６１を容易に交換することができるという利点がある。
【０１２６】
【発明の効果】
請求項１の発明は、主回路を収納する器体と、少なくとも一部が器体から回動自在に露出するハンドルと、少なくともハンドルの操作に応じて主回路の主接点を開閉する開閉機構と、短絡電流が主回路に流れた場合に開閉機構を釈放して主接点を強制的に開極する電磁釈放装置とを備え、電磁釈放装置は、第１鉄心及び第２鉄心を具備し、主回路を形成する通電導体を間に挟む形で第１鉄心を第２鉄心に揺動自在に接離させるとともに第１鉄心を第２鉄心から離れる向きに付勢し第２鉄心が第１鉄心を吸引して第１鉄心と第２鉄心との距離が所定値を下回ったときに開閉機構を釈放してなる回路遮断器において、第２鉄心を第１鉄心と接離する方向に移動自在に配設するとともに、第１鉄心を第２鉄心から離れる向きに付勢する力よりも弱い力で第２鉄心を第１鉄心から離れる向きに付勢したので、通電導体に定格を超える電流が流れた場合には最初に第２鉄心が第１鉄心に接触する向きに移動した後に第１鉄心が第２鉄心に接触する向きに移動するため、短絡電流やコード短絡電流が流れたときには第１及び第２鉄心がそれぞれ電磁吸引力により互いに接触する向きに移動して主接点が強制開極されるが、負荷起動の際に瞬時に流れる突入電流は第１鉄心が移動し始める前に流れなくなることから第１鉄心と第２鉄心との距離が所定値を下回ることがなく、主接点が誤って強制開極されることを防止できるという効果がある。
【０１２７】
請求項２の発明は、請求項１の発明において、第２鉄心と通電導体との間に第２鉄心を第１鉄心から離す向きに弾性付勢する圧縮ばねを介装したので、圧縮ばねを第２鉄心の中心位置に当接させることが容易になるため、第２鉄心をスムーズに移動させることができるという効果がある。
【０１２８】
請求項３の発明は、請求項２の発明において、バイメタルからなる通電導体を一端で固定して他端を揺動自在としてなり、過負荷電流が通電導体に流れた場合に過負荷電流による温度上昇で通電導体の他端が揺動することにより開閉機構を釈放して主接点を強制的に開極する熱動釈放装置を備え、通電導体の中央から固定された一端側寄りの位置に圧縮ばねを介装したので、通電導体の他端が揺動する際の圧縮ばねと第２鉄心との間の距離の変動を抑えて圧縮ばねの位置ずれや脱落が防止できるという効果がある。
【０１２９】
請求項４の発明は、請求項１の発明において、第２鉄心と器体との間に第２鉄心を第１鉄心から離す向きに弾性付勢する圧縮ばねを介装したので、第２鉄心と圧縮ばねを器体内に配設した後に通電導体や第１鉄心を配設することができて組立作業が容易になるという効果がある。
【０１３０】
請求項５の発明は、請求項１〜４の何れかの発明において、主接点を閉極状態にラッチさせるラッチ部材と、器体内で揺動自在に配設され、主接点を開極状態へ移行させるラッチ部材の動きを規制するとともに電磁釈放装置が具備する第１鉄心と第２鉄心との距離が所定値を下回ったときに前記規制が解除される引外し部材とを開閉機構に具備し、引外し部材の揺動する部位に第１鉄心を取着したので、電磁釈放装置においては第１鉄心の動きを引外し部材に伝える部材が不要となり、部品点数を削減できるとともに第１鉄心と引外し部材との距離を縮めることで小型化が図れるという効果がある。
【０１３１】
請求項６の発明は、主回路を収納する器体と、少なくとも一部が器体から回動自在に露出するハンドルと、少なくともハンドルの操作に応じて主回路の主接点を開閉する開閉機構と、短絡電流が主回路に流れた場合に開閉機構を釈放して主接点を強制的に開極する電磁釈放装置とを備え、開閉機構は、主接点を閉極状態にラッチさせるラッチ部材と、器体内に揺動自在に配設されて主接点を開極状態へ移行させるラッチ部材の動きを規制するとともにラッチ部材の動きを規制する方向に付勢され、短絡電流が主回路に流れた場合に電磁釈放装置により前記規制を解除する方向に揺動させられる引外し部材とを具備し、電磁釈放装置は、引外し部材の揺動部位に対して固定鉄心と接離する方向に移動自在に設けた可動鉄心と、主回路を形成する通電導体を可動鉄心との間に挟む形で器体に固定した固定鉄心とを具備し、引外し部材をラッチ部材の動きを規制する方向に付勢する力よりも弱い力で可動鉄心を固定鉄心から離れる向きに付勢し、固定鉄心が可動鉄心を吸引して可動鉄心と固定鉄心との距離が所定値を下回ったときに引外し部材による前記規制を解除してなるので、通電導体に定格を超える電流が流れた場合には最初に可動鉄心が引外し部材の揺動部位に対して固定鉄心に接触する向きに移動した後に引外し部材を揺動しながら可動鉄心が固定鉄心に接触する向きに移動するため、短絡電流やコード短絡電流が流れたときには可動鉄心が引外し部材を揺動しながら固定鉄心に接触する向きに移動して主接点が強制開極されるが、負荷起動の際に瞬時に流れる突入電流は可動鉄心が引外し部材を揺動しながら移動し始める前に流れなくなることから可動鉄心と固定鉄心との距離が所定値を下回ることがなく、主接点が誤って強制開極されることを防止できるという効果がある。
【０１３２】
請求項７の発明は、請求項６の発明において、棒状の主部の先端に鍔部を設けた取付部材を電磁釈放装置に具備し、可動鉄心を表裏に貫通し主部の径よりも大きく且つ鍔部の径よりも小さい径を有する貫通孔に取付部材の主部を挿通するとともに貫通孔に挿通した主部の後端を引外し部材の揺動部位に固定し、取付部材の主部に外挿した圧縮コイルばねを鍔部と可動鉄心との間に配置したので、圧縮コイルばねが鍔部と可動鉄心との間で取付部材の主部に支持されることとなり、圧縮コイルばねの脱落や座屈が防止できるという効果がある。
【０１３３】
請求項８の発明は、請求項７の発明において、複数の取付部材を電磁釈放装置に具備するとともに、各取付部材の主部を挿通する複数の貫通孔を可動鉄心に設けたので、引外し部材の揺動部位に対する可動鉄心の位置ずれを防止して特性を安定化させることができるという効果がある。
【０１３４】
請求項９の発明は、請求項７又は８の発明において、取付部材の主部の後端を挿抜自在に圧入する圧入孔を引外し部材の揺動部位に設けたので、圧縮ばねや可動鉄心を容易に交換することができるという効果がある。
【図面の簡単な説明】
【図１】実施形態１を示す分解斜視図である。
【図２】同上の投入状態を示し、第１側ケースを取り外した状態の側面図である。
【図３】同上の開放状態を示し、第１側ケースを取り外した状態の側面図である。
【図４】同上の背面断面図である。
【図５】同上における第１の電磁釈放装置並びに熱動釈放装置の分解斜視図である。
【図６】同上における第２及び第３の電磁釈放装置の分解斜視図である。
【図７】同上における第２及び第３の電磁釈放装置の斜視図である。
【図８】同上における漏電保護回路並びに試験回路の回路図である。
【図９】同上における零相変流器、第１及び第２の回路基板の構造部位の分解斜視図である。
【図１０】同上における零相変流器、第１及び第２の回路基板の構造部位の斜視図である。
【図１１】同上の背面断面図である。
【図１２】同上の投入状態から第２の電磁釈放装置が動作した状態を示し、第２側ケースを取り外した状態の側面図である。
【図１３】同上の投入状態から第１の電磁釈放装置が動作した状態を示し、第１側ケースを取り外した状態の側面図である。
【図１４】同上の投入状態から第１の電磁釈放装置の第２鉄心が移動した状態を示し、第１側ケースを取り外した状態の側面図である。
【図１５】（ａ）〜（ｅ）は同上における第１の電磁釈放装置の動作説明図である。
【図１６】同上における第１の電磁釈放装置の動作説明図である。
【図１７】実施形態２における第１の電磁釈放装置並びに熱動釈放装置の分解斜視図である。
【図１８】（ａ）〜（ｃ）は同上における第１の電磁釈放装置の動作説明図である。
【図１９】実施形態３における第１引外し板と可動鉄心の分解斜視図である。
【図２０】同上の投入状態を示し、第１側ケースを取り外した状態の側面図である。
【図２１】同上の開放状態を示し、第１側ケースを取り外した状態の側面図である。
【図２２】同上の開放状態を示し、第２側ケースを取り外した状態の側面図である。
【図２３】同上の投入状態から第１の電磁釈放装置が動作して主接点が開極した状態を示し、第１側ケースを取り外した状態の側面図である。
【図２４】同上の投入状態から第１の電磁釈放装置の可動鉄心が第１引外し板に対してのみ移動した状態を示し、第１側ケースを取り外した状態の側面図である。
【図２５】（ａ）〜（ｅ）は同上における第１の電磁釈放装置の動作説明図である。
【図２６】同上における第１の電磁釈放装置の動作説明図である。
【図２７】（ａ）〜（ｅ）は従来例における電磁釈放装置の動作説明図である。
【符号の説明】
１ 器体
２Ａ，２Ｂ 固定接点
３Ａ，３Ｂ 可動接点
５ 開閉機構
６ ハンドル
４１ 第１引外し板
４５ バイメタル
４７Ａ 第１の電磁釈放装置
６０ 第２鉄心
６１ 第１鉄心
６４ 復帰ばね
８１ ねじりばね[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a circuit breaker.
[0002]
[Prior art]
In recent years, a circuit breaker used for a branch circuit in a house is an electric circuit connected to a branch circuit instead of a circuit breaker for a distribution board for houses (refer to JIS C 8370) generally called a safety breaker. Circuit breaker with instantaneous interruption function for cord short-circuit protection that can instantaneously interrupt the electric circuit even with a relatively small short-circuit current, such as when the power cord of the equipment is short-circuited due to damage or deterioration of the coating (JEM 1477, JEM 1477) Reference) is used.
[0003]
The above circuit breaker with instantaneous break function for short circuit protection (hereinafter abbreviated as “circuit breaker”) has an electromagnetic release device with higher sensitivity than the conventional safety breaker, and its operating current (electromagnetic release device) The magnitude of the short-circuit current at which the trip operation is performed) is set to a value having 350 A as the upper limit in the above standard and the lower limit as the current value at which the trip operation is not performed in the overflow test specified in JIS C 8370.
[0004]
An example of such a circuit breaker is described in JP-A-2002-25415. In the conventional example described in this publication, the fixed iron core and the movable iron core are arranged so as to be able to come into contact with each other with the energizing conductor included in the main circuit sandwiched therebetween, and are movable by a leaf spring connecting the fixed iron core and the movable iron core. When the iron core is energized away from the fixed core, and an excessive current such as a short circuit current flows through the conducting conductor, the movable iron core is attracted to the fixed core by the electromagnetic attraction generated between the fixed core and the movable core. An electromagnetic release device is provided in which the movable iron core moves against the spring force of the leaf spring in a direction in contact with the fixed iron core to release the opening / closing mechanism and forcibly open the main contact. The operating current of the electromagnetic release device is larger than the peak value of overflow (solid line A) as shown in FIG. 27A, and the peak of a relatively small short-circuit current (solid line B) that flows when the cord is short-circuited. It is set to a value smaller than the value. The solid line C indicates a large short-circuit current that flows when a circuit is short-circuited.
[0005]
Here, the operation of the electromagnetic release device will be briefly described with reference to FIG. In FIGS. 4B to 4E, the horizontal axis represents time, and the vertical axis represents the distance between the fixed iron core and the movable iron core. First, when overflow flows through the current-carrying conductor, the operating current is set to a value larger than the overflow as described above, so the movable iron core does not move and the main contact is not opened ((c )reference). On the other hand, when a relatively small short-circuit current (hereinafter referred to as “cord short-circuit current”) due to the cord short-circuit flows through the conducting conductor, the operating current is set to a value smaller than the cord short-circuit current as described above. Therefore, as shown in FIG. 4D, the movable iron core is attracted to the fixed core from the time when the cord short-circuit current (see the solid line B in FIG. 1A) exceeds the operating current in a direction to contact the fixed iron core. As the cord short-circuit current increases, the distance between the movable iron core and the fixed iron core becomes narrower, and when the distance between the two falls below a predetermined value, the switching mechanism is released to forcibly open the main contact To do. When a large short-circuit current (hereinafter abbreviated as “short-circuit current”) flows due to a circuit short-circuit, the short-circuit current rises more rapidly than the cord short-circuit current (see the solid line C in FIG. 1A). As shown in FIG. 4E, the distance between the movable iron core and the fixed iron core falls below the predetermined value in a shorter time than when a cord short-circuit current flows, releasing the switching mechanism and forcibly opening the main contact. It will be.
[0006]
[Problems to be solved by the invention]
However, when a load in which a large inrush current flows instantaneously at the time of startup, such as a motor or an inverter, is connected to the branch circuit, the inrush current at the time of start-up is the cord short-circuit current as shown by the solid line D in FIG. If it flows above, the operating current of the electromagnetic release device will be exceeded, the movable iron core will move in the direction of contact with the fixed iron core, and the distance between the movable iron core and the fixed iron core will become narrower as the inrush current increases. In spite of the absence of an abnormality such as a short circuit, there is a problem that when the distance between the two is below a predetermined value, the open / close mechanism is released and the main contact is forcibly opened.
[0007]
The present invention has been made in view of the above problems, and an object of the present invention is to provide a circuit breaker that prevents a main contact from being accidentally forcibly opened due to an inrush current that flows instantaneously when a load is started. There is.
[0008]
[Means for Solving the Problems]
In order to achieve the above object, the first aspect of the present invention provides a container that houses the main circuit, a handle that is at least partially pivotably exposed from the container, and at least the main circuit according to the operation of the handle. An open / close mechanism that opens and closes the main contact; and an electromagnetic release device that releases the open / close mechanism and forcibly opens the main contact when a short-circuit current flows in the main circuit. A second iron core is provided, and the first iron core is swingably contacted with and separated from the second iron core with an energizing conductor forming the main circuit interposed therebetween, and the first iron core is energized in a direction away from the second iron core. In a circuit breaker in which the opening and closing mechanism is released when the second iron core sucks the first iron core and the distance between the first iron core and the second iron core falls below a predetermined value, the second iron core is brought into contact with the first iron core. The first iron core is separated from the second iron core while being movably arranged in the separating direction. The second core is urged away from the first core with a force weaker than the force that is applied at the time. When the current exceeding the rating flows through the conducting conductor, the second core Since the first iron core moves in the direction of contact with the second iron core after moving in the direction of contact with the first iron core, the first and second iron cores contact each other by electromagnetic attraction when a short circuit current or cord short circuit current flows The main contact is forcibly opened when the load is started, but the inrush current that flows instantaneously when the load is started stops flowing before the first iron core starts to move, so the distance between the first iron core and the second iron core Does not fall below a predetermined value, and the main contact can be prevented from being forcibly opened by mistake.
[0009]
The invention of claim 2 is characterized in that, in the invention of claim 1, a compression spring that elastically biases the second iron core in a direction away from the first iron core is interposed between the second iron core and the conducting conductor. Since it becomes easy to make a compression spring contact | abut to the center position of a 2nd iron core, a 2nd iron core can be moved smoothly.
[0010]
According to a third aspect of the present invention, in the second aspect of the invention, the temperature of the overload current is fixed when the conductive conductor made of bimetal is fixed at one end and the other end is freely swingable, and an overload current flows through the conductive conductor. Equipped with a thermal release device that releases the open / close mechanism and forcibly opens the main contact by swinging the other end of the current-carrying conductor as it rises, and compresses it to a position closer to one end that is fixed from the center of the current-carrying conductor The spring is interposed, and the displacement of the compression spring can be prevented from being displaced and falling off by suppressing the fluctuation of the distance between the compression spring and the second iron core when the other end of the conducting conductor swings.
[0011]
The invention of claim 4 is characterized in that, in the invention of claim 1, a compression spring that elastically biases the second iron core in a direction away from the first iron core is interposed between the second iron core and the body. After the second iron core and the compression spring are arranged in the container, the conducting conductor and the first iron core can be arranged, and the assembling work becomes easy.
[0012]
According to a fifth aspect of the present invention, in any of the first to fourth aspects of the present invention, the main contact is latched to be closed in a closed state, and the main contact is brought into an open state. The opening / closing mechanism includes a tripping member that restricts the movement of the latch member to be transferred and that releases the restriction when the distance between the first iron core and the second iron core of the electromagnetic release device falls below a predetermined value. The first iron core is attached to the swinging part of the tripping member. In the electromagnetic release device, a member for transmitting the movement of the first iron core to the tripping member is not required, and the number of parts can be reduced. The size can be reduced by reducing the distance between the iron core and the tripping member.
[0013]
In order to achieve the above object, a sixth aspect of the present invention provides a container that houses the main circuit, a handle that is at least partially exposed from the container in a freely rotatable manner, and at least the main circuit according to the operation of the handle. An open / close mechanism that opens and closes the main contact and an electromagnetic release device that releases the open / close mechanism and forcibly opens the main contact when a short-circuit current flows in the main circuit. The open / close mechanism closes the main contact. The latch member that is latched to the state and the latch member that is swingably disposed in the body and that moves the main contact to the open state is regulated, and the bias is biased in the direction that regulates the movement of the latch member, and the short circuit A tripping member that is swung in a direction to release the restriction by an electromagnetic release device when an electric current flows through the main circuit, and the electromagnetic release device has a fixed iron core with respect to a swinging portion of the tripping member. Possible to move freely in the direction of contact From a force that urges the tripping member in a direction that restricts the movement of the latch member, and includes an iron core and a fixed iron core that is fixed to the container in such a manner that the conductive conductor forming the main circuit is sandwiched between the movable iron core The movable iron core is urged away from the fixed core with a weak force, and when the distance between the movable core and the fixed core falls below a predetermined value when the fixed core sucks the movable core, the restriction by the tripping member is released. When a current exceeding the rating flows through the current-carrying conductor, the movable iron core first moves in a direction in contact with the fixed iron core with respect to the swinging part of the tripping member, and then the tripping member is moved. Since the movable iron core moves in the direction of contact with the fixed iron core while swinging, when the short-circuit current or cord short-circuit current flows, the movable iron core moves in the direction of contact with the fixed iron core while swinging the tripping member. The contact is forcibly opened, but the load The inrush current that flows instantaneously during movement stops before the movable iron core starts to move while tripping the tripping member, so the distance between the movable iron core and the fixed iron core does not fall below a predetermined value, and the main contact It can prevent accidental forced opening.
[0014]
The invention of claim 7 is the invention of claim 6, wherein the electromagnetic release device includes an attachment member having a flange at the tip of the rod-like main portion, and penetrates the movable iron core on the front and back and is larger than the diameter of the main portion. The main portion of the mounting member is inserted into the through hole having a diameter smaller than the diameter of the flange portion and the rear end of the main portion inserted into the through hole is tripped and fixed to the swinging portion of the member. The compression coil spring extrapolated to the center of the mounting member is supported between the collar and the movable iron core, and the compression coil spring is supported between the collar and the movable iron core. The coil spring can be prevented from falling off or buckling.
[0015]
The invention of claim 8 is characterized in that, in the invention of claim 7, a plurality of mounting members are provided in the electromagnetic release device, and a plurality of through holes through which the main parts of the mounting members are inserted are provided in the movable iron core. The position of the movable iron core relative to the swinging part of the tripping member can be prevented and the characteristics can be stabilized.
[0016]
A ninth aspect of the present invention provides the compression spring according to the seventh or eighth aspect, wherein a press-fitting hole for press-fitting the rear end of the main portion of the mounting member is provided in the swinging portion of the tripping member. And the movable iron core can be easily replaced.
[0017]
DETAILED DESCRIPTION OF THE INVENTION
(Embodiment 1)
Hereinafter, Embodiment 1 which applied this invention to the earth-leakage circuit breaker is demonstrated in detail with reference to FIGS.
[0018]
In the present embodiment, two fixings arranged in parallel in the width direction of the container body 1 in the container body 1 configured by connecting the first side case 1A and the second side case 1B made of synthetic resin on both sides. The contacts 2A and 2B, the two movable contacts 4A and 4B, to which the movable contacts 3A and 3B that are detachably opposed to the fixed contacts 2A and 2B are fixed, and the two movable contacts 4A and 4B are driven. The movable contact 3A and 3B are brought into and out of contact with the fixed contacts 2A and 2B through the opening and closing mechanism 5 by the opening and closing operation of the handle 6 (contact / release). The fixed contacts 2A, 2B and the movable contacts 4A, 4B are arranged vertically in the height direction of the body 1, and two fixed contacts 2A in the height direction of the movable contacts 4A, 4B. , 2B, one movable contact 4B and the other movable contact 4A The fixed contact 2A to which the movable contact 3A comes in contact is separated from the fixed contact 2A and 2B at a height position where the movable contact 3A and 3B are not separated from each other when viewed from the width direction of the container 1 with the movable contacts 3A and 3B being separated from each other. It is.
[0019]
An intermediate case 7 molded from a synthetic resin material is fixed in one end portion in the longitudinal direction of the container body 1 so as to be sandwiched between both side cases 1A and 1B, and the inner side wall (outer wall) inside the first side case 1A is fixed. A terminal block 10A constituting an output terminal on the voltage electrode side having a fixed contact 2A provided at one end is accommodated in a section constituted by the concave portion 8 and the vertical wall portion 35 of the intermediate case 7, and the second case of the intermediate case 7 is accommodated. The neutral electrode side or the other voltage electrode side provided with the lower fixed contact 2B at one end in a section constituted by the recess 9 provided on the side case 1B side and the side wall (outer wall) of the second case 1B. The terminal block 10B which comprises an output terminal is accommodated.
[0020]
In the terminal block 10A, an extension piece 11a is integrally extended above a terminal plate 11 bent in a U-shape and one end of a lower piece of the terminal plate 11, and the upper end of the extension piece 11a is perpendicular to the extension piece 11a. A fixed contact 12A that is bent and integrally extended outward with respect to the terminal plate 11, a fixed contact 2A that is caulked and fixed to the upper surface of one end of the fixed contact 12A, and a lower piece of the terminal plate 11 It is comprised with the substantially M-shaped lock spring 13A accommodated in the terminal board 11. FIG. Then, the lower piece of the terminal plate 11 is placed on the bottom inclined surface of the concave portion 8 of the first side case 1A, the extension piece 11a is disposed along the rising wall 8a at one end of the concave portion 8, and the rising wall 8a The fixed contact 12A is led out of the recess 8 beyond the upper end, and is integrally formed between the rising wall 8a and the partition wall 14 rising from the bottom of the first side case 1A in the same manner as the bottom of the recess 8. The terminal block 10 </ b> A is disposed in the recess 8 by disposing the tip of the fixed contact 12 </ b> A on the fixed contact disposition portion 15. The fixed contact placement portion 15 is formed with a recess 15a that allows the lower end of the fixed contact 2A protruding to the lower surface side of the fixed contact 12A to escape. The terminal plate 11 is formed by integrally extending a T-shaped piece 11b upward from the other end of the upper piece, and one end of a side protruding portion at the upper end of the T-shaped piece 11b is formed on the inner surface of the first side case 1A. It mounts on the upper end surface of the formed convex flat part 22. Further, a protrusion 23 is integrally formed on the side surface of the side piece of the terminal plate 11 to be inserted into the holding piece 13b of the locking spring 13A and prevent the locking spring 13A from rattling.
[0021]
The lock spring 13A and the terminal plate 11 constitute a quick connection terminal as a conductor connecting portion. When the intermediate case 7 is superimposed on the first side case 1A, the vertical wall portion at the other end of the first side case 1A. Inserted from the outside through an oblique downward electric wire insertion hole 16A formed by an oblique downward groove 160 having a semicircular cross section and an oblique downward groove 160 having a similar shape on the wall formed on the opposite wall surface of the intermediate case 7. A core wire of an electric wire (not shown) is press-fitted between the upper piece of the terminal plate 11, the upper end of the locking piece 13a of the locking spring 13A, and the upper end of the holding piece 13b, and the end of the locking piece 13a The core wire is locked with respect to the pulling direction, and the core wire is pressed against the upper piece of the terminal plate 11 at the upper end surface of the pressing piece 13b, whereby the core wire is electrically connected and mechanically held. Yes. The wire lock is released by a release handle 17, and the release handle 17 has a rotary shaft 18 provided on a lower side surface thereof rotated in a shaft hole 20 provided on a convex flat portion 22 on the inner side surface of the first side case 1 </ b> A. A shaft (not shown) that is freely pivotally supported and protrudes from the wall surface of the vertical wall portion 35 of the intermediate case 7 is pivotally supported in a recess 37 provided on the other lower side surface. By manually operating and rotating the operating portion 17a exposed to the outside, the drive projection 19 provided at the lower end pushes the tip of one side end of the locking piece 13a of the locking spring 13A to move the locking piece 13a. It can be bent and the lock on the core wire can be released. In the figure, reference numeral 21 denotes a return spring that constantly urges the release handle 17 to rotate in the anti-manual operation direction.
[0022]
On the other hand, the terminal block 10B is basically composed of a terminal plate 11, a lock spring 13B, and a stationary contact 12B, like the terminal block 10A. However, unlike the terminal plate 11 of the terminal block 10A, the terminal block 10B The terminal plate 11 of the block 10B has an extension piece 11c extending downward from one end of the lower piece, and a fixed contact 12B is extended from the tip of the extension piece 11c so as to be parallel to the bottom of the body 1. Further, a back piece 11d extending at a right angle from one end of the side piece of the terminal plate 11 is formed.
[0023]
The lock spring 13B has the same structure as the lock spring 13A, is placed on the lower piece of the terminal plate 11, and a protrusion 23 protruding from the side piece of the terminal plate 11 is inserted into the holding piece 13b. It is like that.
[0024]
The terminal block 10B constitutes the bottom of the concave portion 9 of the intermediate case 7 and places the lower piece of the terminal plate 11 on the lateral wall portion 24 formed so as to extend substantially parallel to the bottom portion of the vessel body 1. The back piece 11d is placed along the vertical wall 25 at one end, and one end of the terminal plate 11 is fitted into a notch 27 formed between the lower end of the vertical wall 25 and one end of the horizontal wall 24, and the extension piece 11c is recessed. When the intermediate case 7 is superimposed on the first side case 1A side, the tip of the fixed contact 12B, that is, the lower surface provided with the fixed contact 2B is the bottom of the first side case 1A. Are placed on the ribs 26, 26. That is, the fixed contact 2B is disposed across the side cases 1A and 1B in a space formed between the side wall 24 of the intermediate case 7, the bulging portion 30 described later, and the side walls of the side cases 1A and 1B. The recess between the ribs 26 is a relief at the lower end of the fixed contact 2B, which is fixed by caulking to the tip of the fixed contact 12B, protruding from the lower surface side of the fixed contact 12B.
[0025]
Further, the tip of the side projecting portion at the upper end of the T-shaped piece 11 b that extends upward from the other end of the upper piece of the terminal plate 11 is the upper end surface of the convex flat portion 22 ′ formed on the wall surface of the intermediate case 7. Placed on.
[0026]
The lock spring 13B and the terminal plate 11 of the terminal block 10B constitute a quick connection terminal as a conductor connecting portion as in the case of the terminal block 10A, and when the intermediate case 7 is superimposed on the second side case 1B, the intermediate case 7 is provided in the vertical wall at the other end of the second side case 1B in the same manner as the oblique downward groove 160 having a semicircular cross section provided in the vertical wall portion at the other end of the recess 9. When the electric wire is inserted from the electric wire insertion hole 16B formed by the oblique downward groove 160, the core wire is locked by the locking piece 13a of the locking spring 13B, and the core wire is attached to the upper piece of the terminal plate 11 by the pressing piece 13b. The wires are pressed to electrically connect the wires and are mechanically locked.
[0027]
The wire locking is released by a release handle 17 ′. Like the release handle 17, the release handle 17 ′ has a rotating shaft 18 provided on the lower side surface provided on the convex flat portion 22 ′ of the intermediate case 7. A shaft 38 that is pivotally supported in the shaft hole 20 and protrudes from the inner wall surface of the second side case 1B is pivotally supported in a recess 37 formed on a side surface thereof. When the operating portion 17a exposed to the outside is manually operated and rotated, the driving projection 19 provided at the lower end pushes the tip of one side end of the locking piece 13a of the locking spring 13B to bend the locking piece 13a. You can now unlock the locked state. In the figure, reference numeral 21 'denotes a return spring that constantly urges the release handle 17' to rotate in the anti-manual operation direction.
[0028]
The intermediate case 7 is formed with a bulging portion 30 that protrudes toward the second side case 1B with respect to the vertical wall portion 35 substantially parallel to the side walls of the two side cases 1A and 1B and contacts the inner surface of the side wall of the second side case 1B. The wall suspended from the lower surface of the bulging portion 30 is the vertical wall 25, and is a recess surrounded by the side wall, the bottom wall, the vertical wall 32 at one end, and the ceiling wall 33 facing the second side case 1B. Is provided on the first side case 1A side. Then, when the intermediate case 7 is abutted against the first side case 1A side, the front end side portion of the fixed contact 12A of the terminal block 10A assembled on the first side case 1A side is placed on the step surface of the bottom wall of the recess. The ceiling wall 33 is arranged along the lower surface of the lateral wall 29 protruding from the inner surface of the first case 1A. The vertical wall 32 is formed with an opening 39 for inserting the free end of the movable contact 4A corresponding to the fixed contact 2A into the recess.
[0029]
On the other hand, inside the other end in the longitudinal direction of the container body 1, the lowermost step among three conductive bars (not shown) respectively disposed at different positions (vertical direction in FIG. 2) in the distribution board. The storage portion 90 for storing and arranging one fixed terminal T1 for plugging and connecting the conductive bar of the voltage electrode, and either the uppermost neutral electrode or the conductive bar of the other voltage electrode for the plugging connection is selected. An inner storage portion 200 is provided in which one selection terminal T2 is movably disposed between at least two positions corresponding to the conductive bars of the neutral electrode and the other voltage electrodes. That is, in this embodiment, it is possible to selectively correspond to a distribution voltage of 100 V if the selection terminal T2 is connected to the conductive bar of the neutral electrode, and 200 V if the selection terminal T2 is connected to the conductive bar of the other voltage electrode. It is a so-called 100V / 200V combined type.
[0030]
The fixed terminal T1 and the selection terminal T2 are both substantially U-shaped, and are composed of blade receiving springs that expand toward the tip after the tips of both side pieces that are parallel to each other are close to each other. It is easy to insert, and the conductive bar is sandwiched between the central adjacent parts.
[0031]
The inner storage portion 200 includes an inner storage portion 200 of the first side case 1A as positioning means for positioning the selection terminal T2 at two positions respectively corresponding to the two conductive bars of the neutral electrode and the voltage electrode. A protrusion 97 having a substantially semicircular cross section is provided in the width direction of the first side case 1A on the end wall surface of the partition to be configured.
[0032]
As a display means for displaying whether the selection terminal T2 is located at a position corresponding to either the neutral electrode or the conductive electrode of the voltage electrode on the wall corresponding to the ceiling part of the inner storage part 200 of the container 1, the inner side Is the columnar display portion 202 formed on the upper portion of the slide member 83 that accommodates the selection terminal T <b> 2 provided in the accommodation portion 200 communicating with the through-hole 201 and can be visually recognized from the outside? The position of the selection terminal T2 can be known depending on whether it is located away from the through hole 201 and cannot be visually recognized from the outside. Further, the slide member 83 can be pushed downward from the outside through the through hole 201 and moved downward. The through-hole 201 is a circular hole formed by abutting a semicircular cut-out hole 201a provided on the upper side walls of the two side cases 1A and 1B.
[0033]
The slide member 83 is formed of a synthetic resin molded product and is formed in a frame shape with both end faces corresponding to both end directions of the container body 1 being opened, and a blade receiving spring constituting the selection terminal T2 is inserted from one end opening. The tip end of the blade receiving spring protrudes from the other end opening, and the selection terminal T2 is disposed so as to be movable in the vertical direction in FIG.
[0034]
A guide groove in the vertical direction in which slide projections 203 formed on both side portions of the slide member 83 are slidably engaged and slid on the inner surfaces of the side walls of both side cases 1A and 1B constituting both side walls of the inner storage portion 200. 204 is formed between two parallel projections 205, and the inner housing portion 200 has the slide member 83 in a state where the slide projections 203 on both sides of the slide member 83 are engaged with the guide grooves 204, 204 on both side walls. At the same time, the selection terminal T2 is stored and held so as to be slidable in the vertical direction. Note that a slide protrusion may be provided on the inner storage portion 200 side, and a guide groove may be provided on the slide member 83 side.
[0035]
As shown in FIG. 1, the slide member 83 is integrally formed with a leg piece 83a extending downward in the figure as shown in FIG. 1, and the lower end portion of the leg piece 83a projects outward. A portion 206 is formed.
[0036]
This protrusion 206 is formed on the outside of the side wall of the first side case 1A constituting the side wall of the inner storage part 200, as shown in FIG. 2, from the slide groove 207 formed upward from the bottom surface of the first side case 1A. It is inserted into the slide groove 207 through an insertion hole (not shown) opened so as to communicate with the inner storage portion 200 at the upper end bottom, and is slidable in the slide groove 207 together with the leg piece 83a in the vertical direction.
[0037]
The slide groove 207 and the insertion hole constitute a guide part for moving the slide member 83 mounted with the selection terminal T2 up and down, and the bottom part of the slide groove 207 is formed to protrude into the inner storage part 200. The back surface of the leg piece 83a inserted upward into the slide groove 207 through an insertion hole formed at the upper end bottom portion of the slide groove 207 can be brought into sliding contact with the bottom portion of the slide groove 207. In addition, a protrusion 207 a that abuts when the protrusion 206 moves to the upper end of the slide groove 207 is provided at the top of the slide groove 207.
[0038]
Thus, the projecting portion 206 constitutes an operating portion that moves the selection terminal T2 in the inner storage portion 200 up and down, and is held by the projecting portion 206 from the outside of the container 1 or pushed up or down by a driver or the like. If the slide movement in the slide groove 207 is performed, the slide member 83 in the inner storage portion 200 is moved up or down by the guide by the slide protrusion 203 and the guide groove 204 together with the selection terminal T2 along with the slide movement. Become.
[0039]
When the slide member 83 is moved by the above operation, the upper end or the lower end of the slide member 83 gets over the positioning projection 97 by its elasticity and the rounded surface of the positioning projection 97, and after the movement, the frame portion 83 is moved to the positioning projection 97. The position of the selection terminal T2 is held by hitting the lower end or the upper end of the tip.
[0040]
The opening / closing mechanism 5 that opens and closes the movable contacts 4A and 4B is a first member that includes an operation plate 43 that is a latch member, a crossbar 40, and a stepped locking portion 41e that locks one end of the operation plate 43. It consists of a tripping plate 41, a second tripping plate 42, a handle 6, a U-shaped link 44 and the like. If an abnormal large current flows due to a ground fault or a short circuit accident in a closed state of one main contact (the fixed contact 2A and the movable contact 3A), the other main contact (fixed) is caused by the first electromagnetic release device 47A. In the closed state of the contact 2B and the movable contact 3B), if an abnormal large current flows due to a ground fault or a short-circuit accident, the second electromagnetic release device 47B causes a leakage protection to flow if a leakage current flows in the main circuit. If an overcurrent such as an overload current further flows through the third electromagnetic release device 48, the open / close mechanism 5 is released by the thermal release device to forcibly open the main contact.
[0041]
The handle 6 includes an operation unit 6a, a rotation unit 6b, and a handle shaft 6c, and a shaft formed on the inner surface of the first case 1A with a handle shaft 6c protruding from the center of both side surfaces of the rotation unit 6b. A hole 49 and a shaft hole 49 formed on the inner side surface of the second side case 1B are rotatably inserted and held between the side cases 1A and 1B. The operating portion 6a is connected to the side cases 1A and 1B. It faces the window hole 50 opened to the upper surface of the container 1 configured in a connected state. Further, a torsion spring 36 is attached to the handle shaft 6c, and the handle 6 is biased by the torsion spring 36 in the opening operation direction at the closing operation position (see FIGS. 2 and 3).
[0042]
An upper shaft 44 a of the U-shaped link 44 is rotatably inserted into a shaft hole 6 d provided at the lower end of the rotating portion 6 b and is connected to the operation plate 43 via the U-shaped link 44.
[0043]
The actuating plate 43 is connected to the handle 6 via the U-shaped link 44 by inserting the lower shaft 44b of the U-shaped link 44 through bearing holes 43a provided on both sides of the center, and moves up and down in the container 1 Arranged freely.
[0044]
The cross bar 40 is inserted into shaft holes 52, 52 formed on the inner side surfaces of both side cases 1A, 1B with shafts 40a projecting on both side surfaces of the upper part, and is pivotally supported between the side cases 1A, 1B. As shown in FIG. 2, a cut groove 54 for fitting the side portion of the movable contact 4A from the lateral direction is formed in the side portion of the first side case 1A slightly below the shaft 40a, and the lower second portion as shown in FIG. A cut groove 55 for fitting the movable contact 4B from the lateral direction is provided on the side portion on the side case 1B side. In the movable contact side end face, the stop piece 130 protruding from the inner surface of the side wall of the intermediate case 7 and the first side case 1A is in a state where the movable contacts 3A and 3B are separated from the fixed contacts 2A and 2B. A concave groove 131 is formed in the width direction so as to be engaged with and abut against the bottom (see FIG. 3).
[0045]
Here, the movable contact 4A is composed of a rigid conductive metal plate, and is inserted into the cut groove 54 of the crossbar 40 from the side, and at a recessed portion 40b (see FIG. 3) provided behind the cut groove 54, When the rear part is urged upward by a coil spring 53 for contact pressure that is compressed between the lower surface of the rear part and the bottom part of the recessed part 40b, and the cross bar 40 rotates about the shaft 40a. Further, the movable contact 4A is rotated about the opening edge of the groove 54, and the movable contact 3A, which is caulked and fixed to the free end, is brought into contact with the corresponding fixed contact 2A.
[0046]
The movable contact 4B is made of a conductive spring thin plate material. When the cross bar 40 is rotated in the closing operation direction, the movable contact 4B is pressed downward to be bent, and from this bent state, the cross bar 40 is rotated in the opening operation direction. The movable contact 3B that is caulked and fixed to the tip is brought into contact with and separated from the fixed contact 2B by the return and the bending and the return.
[0047]
The lower end portion of the cross bar 40 is pressed by a coil spring 62 that is compressed between the lower end portion and a wall 63 that is suspended from the bottom portion of the first side case 1 </ b> A, so that a rotational force is applied.
[0048]
As shown in FIG. 5, the first tripping plate 41 includes a shaft portion 41a, a protrusion portion 41b protruding above the shaft portion 41a, and a pair of leg portions 41c and 41d protruding below the shaft portion 41a. Thus, both ends of the shaft portion 41a are inserted into shaft holes 56, 56 provided on the inner side surfaces of both side cases 1A, 1B, and are supported rotatably between both side cases 1A, 1B, and protruded by a torsion spring 81 The portion 41b is elastically biased in a direction away from the bimetal 45 (clockwise in FIG. 2). A locking portion 41e with which one end of the operating plate 43 is engaged and disengaged is formed at the upper end portion of the projecting portion 41b, and a receiving portion 41g that is pushed and driven by a bimetal 45, which will be described later, protrudes from the tip side surface of one leg portion 41c. In addition, a receiving portion 41f that is pushed and driven by the second tripping plate 42 is provided projectingly on the tip side surface of the other leg portion 41d.
[0049]
The second tripping plate 42 is formed in a substantially square shape in which a facing portion 42a and a receiving portion 42c protrude from a central portion having a shaft hole 42b, and a shaft 31f provided on a partition wall member 31 described later is inserted into the shaft hole 42b. And pivotally supported. A driving piece 42d is provided on the end face of the facing portion 42a so as to face the lower end of the bimetal 46 described later and to be pushed when the bimetal 46 is bent.
[0050]
As shown in FIGS. 1 and 5, the conductive plates 71A and 71B made of thick plate metal material have screw holes 71a through which adjustment screws 77 and 77 ′ are screwed on one end side, as shown in FIGS. A pair of caulking shafts 71b are provided so as to project. Then, a pair of holes 72a in which adjustment plates 72 and 72 'made of a thin metal material, each of which is made by hanging and fixing the bimetals 45 and 46 constituting the thermal release device to one end side, are penetrating on the other end side. The caulking shaft 71b is inserted and caulked to be attached to the lower surfaces of the conductive plates 71A and 71B.
[0051]
One end of the braided wire 79A, one end of which is welded to the fixed terminal T1, is welded to the portion of the bimetal 45 that is fixed to the adjusting plate 72, and the other end of the braided wire 79A is connected to a first circuit board 73 described later. And the other end of the braided wire 79D, one end of which is welded to the movable contact 4A, is welded to a substantially central portion of the bimetal 45, and the fixed terminal T1, the braided wire 79A, the conductive plate 71A, the bimetal 45, and the braided wire. 79D, the movable contact 4A is electrically connected. In addition, the other end of the braided wire 79B having one end welded to the selection terminal T2 is welded to a portion of the other bimetal 46 fixed to the adjustment plate 72 ′, and the current-carrying conductor 80 connected to the movable contact 4B ( The other end of the braided wire 79C whose one end is welded to the bimetal 46 is welded to a substantially central portion of the bimetal 46, which will be described later. The selection terminal T2, the braided wire 79B, the conductive plate 71B, the bimetal 46, the braided wire 79C, the energizing conductor 80, the movable The contact 4B is electrically connected. The adjustment screws 77 and 77 ′ are screwed to change the distance between the adjustment plates 72 and 72 ′ and the conductive plates 71A and 71B, thereby adjusting the lower end positions of the bimetals 45 and 46, that is, the sensitivity of the thermal release device. It is possible.
[0052]
Incidentally, the conductive plates 71 </ b> A and 71 </ b> B and the bimetals 45 and 46 are held by the partition wall member 31. The partition member 31 is made of a synthetic resin molded product having an insulating property, and has a flat partition wall 31a that separates the two bimetals 45 and 46, and both sides of the partition wall 31a in the thickness direction (the width direction of the body 1) from both sides. The conductive plate 71A and the bimetal 45 and the conductive plate 71B and the bimetal 46 are accommodated in the recesses 31c and 31c surrounded by the partition wall 31a and the peripheral wall 31b. A plurality of protrusions 31d are provided so as to face each other on the peripheral walls 31b above the recesses 31c and 31c. The conductive plates 71A and 71B and the bimetal 45, 46 is held by the partition member 31 (see FIGS. 2 and 3). In addition, rectangular cutouts 31e and 31e are formed on the upper peripheral wall 31b of the recesses 31c and 31c in which the conductive plates 71A and 71B are accommodated so that the adjusting screws 77 and 77 'face the recesses 31c and 31c. It is. Further, a shaft 31f to be inserted into the shaft hole 42b of the second tripping plate 42 projects from the bottom of the recess 31c on the side where the conductive plate 71B and the bimetal 46 are accommodated.
[0053]
As shown in FIG. 5, the first electromagnetic release device 47A includes a second iron core 60 formed by bending a magnetic iron plate into a substantially U-shaped plan view having a pair of side pieces 60a, 60b having different lengths, and a rectangular shape. It is comprised with the 1st iron core 61 which consists of a flat magnetic iron plate. The second iron core 60 is placed on a step 31g formed in the peripheral wall 31b on the recess 31c side in which the conductive plate 71A is housed, and one (shorter) side piece in a groove 31h provided in the partition wall 31a. 60a is accommodated in the recess 31c so as to be movably fitted in the front-rear direction (left-right direction in FIG. 2), and is disposed between the bimetal 45 and the peripheral wall 31b (see FIG. 2). On the other hand, the first iron core 61 is formed with a pair of through holes 61a penetrating in the thickness direction, and a pair of protrusions provided on the surface opposite to the engaging portion 41e at the upper end portion of the protruding portion 41b of the first tripping plate 41. The protrusion 41h is inserted into the through hole 61a and caulked to be attached to the first tripping plate 41, and is the tip of the other (longer) side piece 60b of the second iron core 60 as shown in FIG. Opposite the pole face. Here, a cylindrical spring seat 60c protrudes from a portion of the side pieces 60a, 60b of the second iron core 60 facing the bimetal 45, and one end fixed from the center in the longitudinal direction of the bimetal 45 facing the spring seat 60c. Similarly, a cylindrical spring seat 45a is provided at a position closer to the (upper end in FIG. 5) side, and both end portions of a return spring 64 made of a compression coil spring are externally attached to these two spring seats 60c and 45a. A return spring 64 is interposed between the second iron core 60 and the bimetal 45 by being inserted. That is, the second iron core 60 is movable in a direction (left-right direction in FIG. 2) that is in contact with and away from the first iron core 61 with one side piece 60a fitted in the concave groove 31h. 1 It is elastically biased away from the iron core 61. Note that the first iron core 61 is urged away from the second iron core 60 by setting the spring force of the return spring 64 to be weaker than the spring force of the torsion spring 81 that elastically urges the first tripping plate 41. The second iron core 60 is urged away from the first iron core 61 by a force weaker than the force (spring force of the torsion spring 81). If the return spring 64 that elastically biases the second iron core 60 in the direction away from the first iron core 61 is interposed between the second iron core 60 and the bimetal 45 in this way, the return spring 64 is attached to the second iron core 60. Therefore, the second iron core 60 can be moved smoothly. Moreover, since the spring seat 45a is provided in the position near the one end side fixed from the center of the bimetal 45 and the return spring 64 is attached, the return spring 64 and the second iron core 60 when the other end of the bimetal 45 swings. There is an advantage that the positional deviation and dropout of the return spring 64 can be prevented by suppressing fluctuations in the distance between the return spring 64 and the return spring 64.
[0054]
Thus, the side piece of the second iron core 60 when an abnormally large current flows due to a cord short circuit or a circuit short circuit through the bimetal 45 which is a conducting conductor of one pole including the main contact (the fixed contact 2A and the movable contact 3A). Due to the electromagnetic attractive force generated between the magnetic pole surface of 60b and the first iron core 61, the second iron core 60 first moves in the direction approaching the first iron core 61 against the spring force of the return spring 64, and the side piece 60a. After the second iron core 60 moves to a position where it contacts the end surface of the groove 31h, the first iron core 61 is further swung in the direction of approaching the second iron core 60 by electromagnetic attraction, and the first iron core 61 is attached. Further, the first tripping plate 41 is rotated counterclockwise in FIG. In addition, by attaching the first iron core 61 to the first tripping plate 41 in this way, a member that transmits the movement of the first iron core 61 to the first tripping plate 41 (for example, in the second electromagnetic release device 47B). (Such as the second tripping plate 42) is not required, and the number of parts can be reduced, and the distance between the first iron core 61 and the first tripping plate 41 can be reduced.
[0055]
As shown in FIG. 6, the second electromagnetic release device 47B includes a fixed iron core 57 formed by bending a magnetic iron plate into a substantially U shape in plan view, a movable iron core 58 formed of a rectangular flat magnetic iron plate, and a movable iron core. 58 is constituted by a leaf spring 59 which is an elastic member which is supported in a swingable manner on both end magnetic pole surfaces of the fixed iron core 57 and elastically urges the movable iron core 58 in a direction away from the fixed iron core 57. The conducting conductor 80 has an inner piece 80a in which one end of the braided wire 79C is welded to the front end portion, and an outer piece 80b that extends substantially L-shaped from the rear end of the inner piece 80a and faces the inner piece 80a substantially in parallel. The rear end of the movable contact 4B is connected to the front end of the outer piece 80b.
[0056]
The movable iron core 58 is fixed to the leaf spring 59 by inserting and fixing the projections 58a and 58a projected on the surface on the fixed iron core 57 side into holes 59b and 59b formed at one end of the central piece 59a of the leaf spring 59. It is swingably supported. On the other hand, the leaf spring 59 is arranged so that both side pieces 59c, 59c formed by bending on both sides of the central piece 59a are arranged along the outer surfaces of the both side pieces 57a, 57a of the fixed iron core 57, and are arranged at the ends of the both side pieces 59c, 59c. The engaging pieces 59d and 59d that protrude in the direction are engaged with recesses 57b and 57b formed at the outer corners of the fixed iron core 57, whereby the inner piece 80a of the conductive conductor 80 is fixed to the fixed iron core as shown in FIG. The movable iron core 58 is sandwiched between the inner piece 80a and the outer piece 80b so that the movable iron core 58 is sandwiched between the inner piece 80a and the outer piece 80b. At this time, the magnetic pole surface, which is the tip of both side pieces 57a, 57a of the fixed iron core 57, opposes the movable iron core 58 through the space between the center piece 59a of the leaf spring 59 and both side pieces 59c, 59c.
[0057]
Thus, when an abnormal large current such as a short-circuit current due to a circuit short circuit flows in the conducting conductor 80 electrically connected to the movable contact 3B constituting the main contact of the other pole, both side pieces of the fixed core 57 The movable iron core 58 is attracted and oscillated by the electromagnetic attractive force generated on the magnetic pole surfaces of 57a and 57a. In addition, since the fixed iron core 57 and the movable iron core 58 are connected to each other by the leaf spring 59 in this way, the second electromagnetic release device 47B can be easily assembled into the body 1 as will be described later. It is.
[0058]
Here, the direction of the electromagnetic attracting force generated on the magnetic pole surfaces of the both side pieces 57a, 57a of the fixed iron core 57 by the current flowing through the inner piece 80a of the current-carrying conductor 80, and the both side pieces 57a of the fixed iron core 57 by the current flowing through the outer piece 80b. The direction of the electromagnetic attractive force generated on the magnetic pole surface of 57a is made the same, and the electromagnetic attractive force for attracting the movable iron core 58 is strengthened so that the main contact is quickly opened.
[0059]
On the other hand, the third electromagnetic release device 48 is configured by winding an exciting coil 68 around the fixed iron core 57 of the second electromagnetic release device 47B. That is, as shown in FIG. 6, a coil bobbin 69 formed in a rectangular tube shape with one side opened by an insulating material such as a synthetic resin is protruded from the side pieces 57a and 57a of the fixed iron core 57 from both ends in the axial direction. As shown in FIG. 7, a coil 68 is wound between outer casings 69a and 69a provided at both ends of the coil bobbin 69 in the axial direction. In addition, in the vicinity of the opened side surfaces of the outer casings 69a and 69a of the coil bobbin 69, substantially cubic support portions 69b and 69b having insertion holes 69c are provided so as to protrude from one end of a substantially L-shaped terminal pin 69d. The end portions 68a of the coils 68 are respectively connected and electrically connected to one end portions of the terminal pins 69d protruding from the insertion holes 69c.
[0060]
Thus, when a leakage current flows due to a ground fault, the leakage protection circuit 51, which will be described later, energizes the coil 68 through the terminal pin 69d to excite the fixed core 57, and both side pieces 57a, 57a of the fixed core 57 are excited. An electromagnetic attractive force is generated on the magnetic pole surface of the magnetic core surface so that the movable iron core 58 is attracted and swung. That is, the fixed iron core 57, the movable iron core 58, and the leaf spring 59 constituting the second electromagnetic release device 47B by winding the coil 68 around the fixed iron core 57 are also used as the third electromagnetic release device 48 for protection against leakage. Therefore, the number of parts can be reduced and the space can be saved compared to the case where the electromagnetic release device for high current protection and the electromagnetic release device for leakage protection are configured with independent parts for each pole. The size and size can be reduced.
[0061]
Further, since the energizing directions of the coil 68 and the energizing conductor 80 (inner piece 80a) between the fixed iron core 57 and the movable iron core 58 coincide with each other, when the third electromagnetic release device 48 is operated by energizing the coil 68. The electromagnetic attractive force generated on the magnetic pole surfaces of the both side pieces 57a and 57a of the fixed iron core 57 can be increased, and the main contact can be opened quickly. Further, since the coil 68 is wound around the fixed iron core 57, the coil 68 does not move, so that the coil 68 can be prevented from being disconnected. However, the coil 68 may be wound around the movable iron core 58.
[0062]
The leakage protection circuit 51 has the circuit configuration shown in FIG. 8, and the voltage circuit (braided wire 79A) of the main circuit and the circuit of the neutral electrode or the other voltage electrode (braided wire 79B) are inserted. If the current flowing through each pole of the main circuit is unbalanced due to a leakage current such as a ground fault current, a current corresponding to the degree of unbalance between the output terminals of the zero-phase current transformer ZCT ( Detection current) flows. This detection current is an alternating current and is clamped by a clamp circuit composed of diodes D1 and D2 connected in antiparallel, and the detection current is converted into a voltage by charging the smoothing capacitor C1 through the resistor R1. The voltage across the smoothing capacitor C1, that is, the detected voltage converted from the detected current is input to the leakage current determination circuit 51a.
[0063]
The power source of the leakage current determination circuit 51a is connected to the series circuit of the diode D3, resistors R2 to R5, and the smoothing capacitor C2 between the two poles of the main circuit through the coil 68 of the third electromagnetic release device 48 from the terminal pin 69d. The voltage across the smoothing capacitor C2 is applied to the power supply terminal and the ground terminal of the leakage current determination circuit 51a. A series circuit of a coil 68, a thyristor SCR, and a diode D3 is connected between the two poles of the main circuit, and a control signal output from the output terminal of the leakage current determination circuit 51a is applied to the gate of the thyristor SCR. To turn on the thyristor SCR. A filter circuit including a capacitor C0 and a resistor R0 is connected between both ends of the thyristor SCR.
[0064]
The leakage current determination circuit 51a compares the detected voltage with a predetermined threshold, charges or discharges the capacitor C3 according to the comparison result, and outputs a control signal from the output terminal according to the voltage across the capacitor C3. Configured to delay results. Therefore, when a leakage current flows in the main circuit, the thyristor SCR is turned on by the control signal, and the coil 68 is energized to operate the third electromagnetic release device 48 and the movable iron core 58 is attracted to the fixed iron core 57. The leakage current determination circuit 51a is formed of an integrated circuit, and is externally connected with the capacitor C3 and a resistor R6 that determines a time constant for discharging the capacitor C3 after detecting leakage.
[0065]
Between the two poles of the main circuit, a test circuit 70 comprising a series circuit of a resistor RT, a normally open test switch SW, and a lead 70a inserted through the zero-phase current transformer ZCT is connected. That is, by turning on the test switch SW and passing a current through the lead 70a, an unbalanced current is caused to flow to the primary side of the zero-phase current transformer ZCT to create a pseudo-leakage state, and the leakage protection circuit 51 operates normally. You can test whether or not you want to. A surge absorbing element SA is connected in parallel to the resistor RT and the test switch SW.
[0066]
By the way, the plurality of types of circuit components constituting the leakage protection circuit 51 and the test circuit 70 are mounted on the first and second circuit boards 73 and 74 formed of a printed wiring board as shown in FIG. The first circuit board 73 includes high-power circuit components (resistors R2 and R3, a diode D3, a test circuit 70, a high-power circuit constituting the left-hand high-power circuit from the boundary line W indicated by a dotted line in the circuit diagram of FIG. A low-power circuit component (leakage current determination circuit 51a, clamp circuit, smoothing capacitor C1, zero-phase) constituting the low-power circuit on the right side from the boundary line W is mounted on the second circuit board 74. Current transformer ZCT, etc.) and a thyristor SCR are mounted. The test switch SW includes a movable contact plate 76a having one end bonded to the first circuit board 73 and supported to be swingable, and a pin mounted on the first circuit board 73 so as to face the movable contact plate 76a. When the test button 78 that is movably disposed on the free end side of the movable contact plate 76a is being pushed, the movable contact that is pushed and driven by the test button 78. The plate 76a contacts the fixed contact 76b and is turned on.
[0067]
The zero-phase current transformer ZCT has a ring-shaped core (not shown) around which a winding (not shown) is wound as shown in FIG. The pair of output terminals 75a projecting from the end portions of the housing 75 facing the axial direction of the core are inserted into the notches 74a and 74a provided on the upper portion of the second circuit board 74, and the housing 75 is connected to the second circuit. The output terminal 75a is mounted by soldering it to a wiring pattern (not shown) on the back surface in a state of being in close contact with the surface of the substrate 74.
[0068]
Further, as shown in FIG. 9, a contact pin 67 as a plurality of attachment portions for attaching the first and second circuit boards 73 and 74 to the housing 75 of the zero-phase current transformer ZCT. 1 ~ 67 Five Projecting from both side surfaces in the axial direction. These contact pins 67 1 ~ 67 Five Is made of metal, has its axial direction coincided with the axial direction of the zero-phase current transformer ZCT, and both ends protrude from the side surfaces of the housing 75 and are insert-molded into the housing 75 so as to face the first circuit board 73. Contact pin 67 on the side 1 ~ 67 Five A boss 75 c that covers the surface of the housing 75 is formed integrally with the housing 75.
[0069]
On the other hand, each of the first and second circuit boards 73 and 74 has contact pins 67. 1 ~ 67 Five Through-holes 73a and 74b are respectively drilled, and contact pins 67 are inserted through the through-holes 73a and 74b. 1 ~ 67 Five The first and second circuit boards 73 and 74 are distributed and attached to both side surfaces in the thickness direction (axial direction) of the zero-phase current transformer ZCT. At this time, the contact pin 67 1 ~ 67 Four Serves as a current path between the two circuit boards 73 and 74, and the contact pin 67 1 ~ 67 Five The circuit components mounted on the first and second circuit boards 73 and 74 are electrically connected via the. In addition, through holes 73b through which terminal pins 69d constituting the third electromagnetic release device 48 are respectively inserted are formed in the lower part of the first circuit board 73, and terminal pins 69d inserted into the respective through holes 73b are formed. The coil 68 is electrically connected to the leakage protection circuit 51 by joining the end portion to the wiring pattern. Further, a contact pin 67 is provided in the vicinity of the through hole 75b opened in the center of the housing 75. Five This contact pin 67 is provided. Five Becomes the lead 70a of the test circuit 70 which penetrates the core of the zero-phase current transformer ZCT. The first and second circuit boards 73 and 74 are provided with circular insertion holes 73c and 74c that communicate with the through holes 75b of the housing 75 and through which the braided wires 79A and 79B are inserted. The first circuit board 73 has one end of a lead wire 82A connected to one pole of the main circuit (the pole having the main contact of the fixed contact 2A and the movable contact 3A) via the conductive plate 71A, and the main circuit. The other end of the lead wire 82B having one end welded to the connecting member 99 for connecting to the other pole (the pole having the main contact of the fixed contact 2B and the movable contact 3B) is connected.
[0070]
Thus, a plurality of types of circuit components constituting the leakage protection circuit 51 are mounted on the first and second circuit boards 73 and 74, and the first and second circuits are disposed on both sides in the thickness direction of the zero-phase current transformer ZCT. Since the boards 73 and 74 are arranged and accommodated in the container 1, each circuit board 73, 74 is compared with the case where the leakage protection circuit 51 and the zero-phase current transformer ZCT are mounted on one circuit board as in the prior art. The size of 74 in the longitudinal direction can be reduced, and the body 1 can be miniaturized. Further, a contact pin 67 as a mounting portion on the housing 75 of the zero-phase current transformer ZCT. 1 ~ 67 Five By providing this, the zero-phase current transformer ZCT can be easily attached to the first and second circuit boards 73 and 74. Further, the mounting portion is made of a metal contact pin 67. 1 ~ 67 Four Since the first and second circuit boards 73 and 74 are electrically connected to each other, the current path between the circuit boards 73 and 74 is different from that in the case where wiring is separately performed using a lead wire or the like. There is an advantage that it can be formed easily, and the contact pin 67 1 ~ 67 Five Can be insulated from the winding of the zero-phase current transformer ZCT by insert molding in the housing 75.
[0071]
Contact pin 67 Five Since the first and second circuit boards 73 and 74 are attached to the zero-phase current transformer ZCT, the lead 70a of the test circuit 70 can be easily used as the core of the zero-phase current transformer ZCT. Can be inserted. Further, a high-power circuit component constituting a high-power circuit is mounted on the first circuit board 73, and a weak-power circuit component mainly constituting a low-power circuit is mounted on the second circuit board 74. Therefore, it is possible to mount more circuit components on the second circuit board 74 on which light-electric circuit components that can shorten the insulation distance compared to the high-electric system are mainly mounted. Here, the lead wire 82A for connecting to one pole of the main circuit and the lead wire 82B for connecting to the other pole are connected to the first circuit board 73 on which a high-voltage circuit component is mounted. In the second circuit board 74, there is an advantage that the circuit components can be arranged without considering the insulation distance from the connection position of the lead wires 82A and 82B.
[0072]
Thus, when assembling the earth leakage breaker of this embodiment, first, the terminal block 10A is housed in the recess 8 of the first side case 1A, and the release handle 17 is assembled together with the return spring 21 at a fixed position. Further, the handle 6 is assembled together with a torsion spring 36 at a predetermined position. Then, the cross bar 40 is fitted with the movable contact 4A in the cut groove 54, and the coil spring 53 is housed in the recess, and is rotatably arranged with the coil spring 62 at a predetermined position of the first side case 1A. Further, the operation plate 43 is connected to the handle 6 by a link 44.
[0073]
In addition, the fixed terminal T1 is accommodated in the accommodating portion 90 provided at the bottom of the other end of the container 1, and the inner side is configured when the selection terminal T2 is abutted with the second side case 1B together with the slide member 83. It is stored in the inner compartment of the first side case 1 </ b> A corresponding to the storage unit 200. Further, the leg piece 83a of the slide member 83 is inserted into the slide groove 207 formed on the outer side surface of the side wall of the first side case 1A through the insertion hole to expose the protruding portion 206 to the outside.
[0074]
Furthermore, the separation wall 91 formed in the height direction of the first side case 1A along the inner storage portion 200, and in the height direction facing the separation wall 91 at a substantially longitudinal center of the first side case 1A. First and second circuit boards 73 attached to the zero-phase current transformer ZCT with the second circuit board 74 having a long longitudinal dimension as the partition wall 91 side, in the upper part of the space between the formed separation wall 65, 74 is accommodated, and the first and third electromagnetic release devices 47B and 48 are accommodated in the lower portion of the space. Here, two ribs 92 are provided along the width direction of the container body 1 in the vicinity of the partition wall 91 at the bottom of the first side case 1A, and a fitting groove formed between the two ribs 92. By fitting the lower end portion of the second circuit board 74 to 92a, the longitudinal direction thereof substantially coincides with the height direction of the first side case 1A, and the axial direction of the zero-phase current transformer ZCT is the first side case. The second circuit board 74 is positioned and fixed so as to substantially coincide with the longitudinal direction of 1A.
[0075]
In addition, rectangular window holes 98 are respectively opened on the side walls of the opposite cases 1A and 1B facing the zero-phase current transformer ZCT, and the portion with the largest width dimension of the housing 75 is inserted into the window hole 98 to escape the housing 75. It is said. That is, since the width dimension of the housing 75 of the zero-phase current transformer ZCT is slightly larger than the width dimension of the first and second circuit boards 73 and 74, the width dimension of the container body 1 is adjusted to the width dimension of the housing 75. Although a useless space is generated, by providing the window hole 98 and releasing the housing 75 as described above, it is possible to prevent the useless space from being generated and to reduce the width dimension of the body 1. However, the width dimensions of the housing 75 and the container body 1 are set so that the housing 75 inserted into the window hole 98 does not protrude from the outer side surfaces of the side walls 1A and 1B.
[0076]
On the other hand, the second and third electromagnetic release devices 47B and 48 are arranged on the bottom of the first side case 1A in the lower part of the space with the movable iron core 58 in the height direction of the body 1 as shown in FIG. A zero-phase current transformer ZCT is arranged above the fixed iron core 57 in the height direction of the vessel body 1. Thus, the fixed iron core 57 and the movable iron core 58 connected by the leaf spring 59 are arranged at the bottom of the vessel body 1 along the height direction of the vessel body 1, and the axial direction is set on the upper portions of the fixed iron core 57 and the movable iron core 58. If the zero-phase current transformer ZCT is arranged so as to be substantially coincident with the longitudinal direction of the container body 1, the extending direction of the conducting conductor 80 sandwiched between the fixed iron core 57 and the movable iron core 58 is made coincident with the longitudinal direction of the container body 1. Therefore, the size of the container body 1 in the height direction can be reduced. Further, by arranging the zero-phase current transformer ZCT at the upper part in the height direction of the fixed iron core 57 and the movable iron core 58, the size in the longitudinal direction of the body 1 can be reduced. Furthermore, since the axial direction of the zero-phase current transformer ZCT coincides with the longitudinal direction of the body 1, it is easy to penetrate the main circuit circuit (braided lines 79A and 79B) through the zero-phase current transformer ZCT. Yes. Alternatively, when the braided wires 79A and 79B are incorporated in the first-side case 1A in a state where the braided wires 79A and 79B are passed through the zero-phase current transformer ZCT in advance, the distance for drawing the braided wires 79A and 79B in the container 1 may be short. In addition, since the movable iron core 58 is disposed on the bottom side of the body 1, the suction operation of the movable iron core 58 is not affected by the zero-phase current transformer ZCT, and the opening characteristics of the main contact described later are stabilized. Can do.
[0077]
Here, the movable contact 4B, the rear end of which is connected to the front end of the outer piece 80b, has a separating wall 65 located at a slightly upwardly inclined portion at the center thereof slightly above the bottom of the first side case 1A. It is arranged between the partition wall 95 extended from the lower end of the first side case 1A toward the other end of the first side case 1A, and further inclined and extended upward from the parallel portion, and the bottom of the first side case 1A. The free contact side of the movable contact 4 </ b> B is disposed in a space where the fixed contact 12 </ b> B is disposed via the notch 14 a of the partition wall 14. At this time, the plurality of ribs 96 projecting from the lower surface of the parallel portion of the partition wall 95 and the bottom portion of the first side case 1A are fixed with the rear end portion of the movable contact 4B interposed therebetween. At this time, the connection member 99 connected to the first circuit board 73 and the lead wire 82B is sandwiched and fixed between the bottom of the first side case 1A and the movable contact 4B, and the leakage protection circuit 51 and the test circuit 70 are fixed. Is connected to the electric circuit of one pole.
[0078]
Further, the partition member 31 holding the conductive plates 71A and 71B and the bimetals 45 and 46 is accommodated in the space between the separation wall 65 and the partition wall 95. At this time, the partition member 31 is positioned in the space of the body 1 by placing the inclined part inclined obliquely upward of the lower peripheral wall 31 b of the partition member 31 along the inclined part of the partition wall 95. Thus, since the first circuit board 73 is disposed on the side close to the bimetals 45 and 46 in the longitudinal direction of the container 1, the distance between the second circuit board 74 and the bimetals 45 and 46 is increased. Thus, it is possible to suppress the influence of heat generated by the bimetals 45 and 46 on weakly-electric circuit components that are weak against heat, such as an IC (leakage current determination circuit 51a) mounted on the second circuit board 74.
[0079]
Furthermore, after the second iron core 60 is disposed in the recess 31c together with the return spring 64, the first trip plate 41 is disposed so as to be rotatable in a fixed position together with the torsion spring 81, and the second trip plate 42 is disposed in a fixed position. It is arranged to be freely rotatable. At this time, the receiving portion 42 c of the second tripping plate 42 faces the distal end portion of the movable iron core 58.
[0080]
In this way, as shown in FIG. 11, the intermediate case 7 and the terminal block 10B housed in the recess 9 of the intermediate case 7, the release handle 17 ′ and its return spring 21 ′ are arranged on the first side case 1A side. After the assembly, the intermediate case 7 in which the terminal block 10B, the release handle 17 ′, and the return spring 21 ′ are assembled in the recess 9 is disposed so as to overlap the first case 1A side.
[0081]
Here, when the intermediate case 7 is disposed at a fixed position on the first side case 1A side, the free end side of the movable contact 4A is disposed in the recess through the opening of the vertical wall and is provided in the terminal block 10A. The distal end side portion of the fixed contact 12 </ b> A is placed on the step surface of the bottom wall and the shaft is fitted into the recess 37 of the release handle 17.
[0082]
On the other hand, the stationary contact 12B provided in the terminal block 10B is placed on the rib 26 on the bottom of the first side case 1A. Further, the lower surface of the downward stepped portion that can be formed at the end of the intermediate case 7 is placed on a flat surface formed on the end wall of the first side case 1A.
[0083]
In this state, the second side case 1B is overlapped and coupled to the first side case 1A side. At this time, the claw-like hooking locking portions 101 at the tips of the elastic locking pieces 100 at the upper and lower ends of the both ends integrally projecting from the first side case 1A to the second side case 1B correspond to the second side case 1B side. The first case 1 </ b> A and the second case 1 </ b> B are coupled and fixed by the protrusion-like hooked portion 102 provided as described above to constitute the container 1 (see FIG. 11 and the like). When the first side case 1A and the second side case 1B are uncoupled and fixed, a driver is inserted into the second side case 1B through the release holes 150 corresponding to the hooked portions 102. The second side case 1 </ b> B can be removed from the first side case 1 </ b> A by pressing the hook locking portion 101 of each elastic locking piece 100 upward to remove the hooked state with the hooked portion 102.
[0084]
By attaching the second side case 1B, the shaft 40a of the cross bar 40 and the shaft portion 41a of the first tripping plate 41 are rotatable in the shaft holes 52 and 56 provided on the inner surface of the second side case 1B. Inserted into.
[0085]
Further, the heads of the adjusting screws 77 and 77 ′ corresponding to the bimetals 45 and 46 face the opening 104 opened on the upper surface of the container body 1 through the notch 31 e of the partition wall member 31, and an operation test after assembly is performed. The operation adjusting screws 77 and 77 ′ are screwed through the opening 104 so that an optimum operating point is sometimes obtained, so that the tip of the bimetal 45, the leg 41 c of the cross bar 40, the tip of the bimetal 46, and the second The distance between the trip plate 42 and the drive piece 42d is adjusted, and after the adjustment, the lid 106 is fitted into the peripheral portion of the opening 104 of the container 1 by using its elasticity to cover the opening 104.
[0086]
Here, the bimetals 45 and 46 are juxtaposed with the width direction of the container body 1 as the width direction while being held by the partition wall member 31, so that the dimensions in the width direction of the container body 1 are reduced. Further, since the displacement direction is set in the direction away from the second circuit board 74 and the first and third electromagnetic release devices 47B and 48 along the longitudinal direction of the container 1, the bimetal 45 and 46 and the first metal And the space | interval with the 3rd electromagnetic release apparatuses 47B and 48 and zero phase current transformer ZCT (2nd circuit board 74) can be narrowed, and size reduction of the longitudinal direction of the body 1 can be achieved.
[0087]
In addition, since the bimetals 45 and 46 are separated from each other by the partition wall 31a of the partition wall member 31, it is possible to achieve insulation between the bimetals 45 and 46 by the partition wall 31a and to narrow the interval. Further, by arranging the zero-phase current transformer ZCT across the partition wall 31a in the width direction of the body 1, the braided wires 79A and 79B connected to the bimetals 45 and 46 are passed through the zero-phase current transformer ZCT. It is easy. Furthermore, since the first and third electromagnetic release devices 47B and 48 including the fixed iron core 57 and the movable iron core 58 are also arranged so as to straddle the partition wall 31a in the width direction of the body 1, the fixed iron core 57 and the movable iron core 58 are also disposed. The width dimension of the main contact can be sufficiently increased, and the time required for opening the main contact can be shortened by increasing the electromagnetic attractive force.
[0088]
Thus, the selection terminal T2 and the fixed terminal T1 are respectively stored in the inner storage part 200 and the storage part 90 inside the other end of the container body 1, and one end of the container body 1 corresponds to these terminals T1 and T2. The insertion portions 209a to 209c that are open so as to extend over the end surface and both side surfaces of the container body 1 are formed in the portion. Further, a pair of wire insertion holes 16A and 16B opened obliquely upward are formed in parallel at one end of the vessel body 1.
[0089]
Therefore, the load side electric wires are inserted into the electric wire insertion holes 16A and 16B, respectively, and connected to the terminal blocks 10A and 10B, and the conductive bar of the voltage electrode is inserted into the fixed terminal T1 in the width direction via the insertion portion 209c. By connecting and connecting the conductive bar of the neutral electrode or the other voltage electrode to the selection terminal T2 in the width direction via the insertion portion 209a or 209b, the leakage breaker of this embodiment can be inserted into the electric circuit. It will be possible.
[0090]
By the way, as shown in FIG. 1, a projecting portion 105 through which an insertion hole 105a for inserting the test button 78 is provided is provided in the vicinity of the opening 104 of the second side case 1B, and the test button 78 is formed with a bifurcated tip. Is inserted into the insertion hole 105a from above and the locking step 78a is locked to the periphery of the insertion hole 105a in the container 1 so that the test button 78 is movable in the height direction of the container 1 and is prevented from coming off. It is attached to the projecting part 105. The tip of the test button 78 is opposed to the movable contact plate 76a of the test switch SW mounted on the second circuit board 74. By pressing the test button 78, the movable contact plate 76a is moved at the tip. The test switch SW can be turned on by being pushed and brought into contact with the fixed contact 76b. The lid 106 is provided with a semicircular cutout 106a through which the test button 78 is inserted in order to avoid interference with the test button 78.
[0091]
Here, since the window hole 98 in which the housing 75 of the zero-phase current transformer ZCT is partially exposed is opened on both sides of the container 1, foreign matter intrusion into the container 1 from the window hole 98 is prevented. At the same time, in order to improve appearance, an insulating sheet (not shown) formed of a sheet-like material having an insulating property in a rectangular tube shape is attached to the body 1 to cover the window hole 98. Yes.
[0092]
Next, the operation of the present embodiment will be described with reference to FIGS. 2 and 3 and FIGS. FIG. 3 shows an open state. In this open state, the operation portion 6a of the handle 6 is exposed in an inverted manner from the window hole 50, and the engagement between one end of the operating plate 43 and the first tripping plate 41 is released. It is in the state. The crossbar 40 is urged by the coil spring 62 so as to rotate counterclockwise in FIG. 3, and the movable contact 4A inserted through the groove 54 of the crossbar 40 moves the free end upward. The movable contact 4B inserted into the kerf 55 is in a state where the free end is moved upward by its spring elastic force, and the movable contact 3A provided at each free end. , 3B are separated from the corresponding fixed contacts 2A, 2B.
[0093]
When the operation portion 6a of the handle 6 is rotated counterclockwise in FIG. 3 in this state, the upper shaft 44a of the link 44 is pushed downward, and the link 44 pushes down the operating plate 43 by the lower shaft 44b. By pushing down the operating plate 43, one end (the left end in FIG. 3) of the operating plate 43 hits the locking portion 41e of the first tripping plate 41, and the operating plate 43 rotates clockwise in FIG. The other end (right end in FIG. 3) of the operating plate 43 hits the protrusion 84 provided at the upper end of the cross bar 40, and the cross bar 40 is rotated clockwise in FIG. 3 against the spring bias. .
[0094]
By this rotation, the movable contact 4B inserted into the groove 55 of the cross bar 40 bends in the direction of moving the free end downward, and the free end movable contact 3B is brought into contact with the fixed contact 2B. Further, the movable contact 4A inserted through the kerf 54 rotates clockwise in FIG. 3 so that the movable contact 3A at its free end contacts the fixed contact 2A. This contact is delayed from the time when the movable contact 3B contacts the fixed contact 2B.
[0095]
When the handle 6 is further rotated, the upper shaft 44a moves to the right as shown in FIG. 2 from the line connecting the position of the lower shaft 44b of the link 44 and the rotation center of the handle 6, and in this state the handle 6 The torsion spring 36, the coil spring 62 for urging the cross bar 44, and the spring force of the movable contact 4B are balanced so that one end of the operating plate 43 and the latching portion 41e of the first trip plate 41 are latched. Is maintained and the input state of FIG. 2 is maintained.
[0096]
Now, when the operating portion 6a of the handle 6 is rotated clockwise in FIG. 2 in the closed state, the position of the upper shaft 44a of the link 44 is a line connecting the rotation center of the handle 6 and the lower shaft 44b in FIG. Since the leftward movement of the actuating plate 43 in FIG. 2 and the locking portion 41e of the first tripping plate 41 are released, the crossbar 40 is moved by the biasing force of the coil spring 62. In FIG. 2, the handle 6 is rotated counterclockwise, and the handle 6 is rapidly returned to the OFF side by the biasing force of the torsion spring 36. As the cross bar 40 rotates counterclockwise in FIG. 2, the movable contact 4A rotates counterclockwise in FIG. 2 to move the free end upward, and the movable contact 3A is separated from the fixed contact 2A. Further, the movable contact 4B is not pushed downward, and is returned to its original state by its spring force, so that the movable contact 3B at the free end is separated from the fixed contact 2B. This separation is delayed from the time when the movable contact 3A is separated from the fixed contact 2A. This delay is the same during forced opening described later.
[0097]
Here, since the opening and closing of the main contacts of both poles is delayed as described above, the arc generated when the contacts are opened and closed is only the movable contact 4A on the rigid body side, and the arc of the movable contact 3B made of a spring material. It is possible to prevent exhaustion due to.
[0098]
Further, the stoppers 130 formed in both the cases 1A and 1B and the intermediate case 7 are inserted into the concave groove 131 formed in the width direction of the front end surface of the cross bar 40 that rotates when the main contact is opened, and the concave groove 131 is engaged. Because of the contact with the bottom of the container 1, there is no risk that an arc generated in one section will wrap around from the crossbar 40 side on the back side of the container 1 and enter the other section. Prevent short circuit.
[0099]
Now, when an overcurrent flows through the load in the above-described input state shown in FIG. 2, the bimetals 45 and 46 generate heat due to the overcurrent and are displaced in a curved manner. Here, the bimetals 45 and 46 suspended from above are displaced so that their lower ends move in the right direction in FIG. 2, and the lower ends of the bimetal 46 push the drive piece 42d of the second tripping plate 42 in the right direction in FIG. The lower end of the bimetal 45 pushes the receiving portion 41g at the tip of the leg portion 41c of the first tripping plate 41 in the right direction in FIG. Then, the displacement of the bimetal 46 causes the second trip plate 42 to rotate clockwise in FIG. 2, and the opposing portion 42a of the second trip plate 42 pushes the receiving portion 41f of the first trip plate 41 to the right. The first tripping plate 41 rotates counterclockwise in FIG. 2 when the receiving portion 41g is pushed by the bimetal 45 and the receiving portion 41f is pushed by the second tripping plate.
[0100]
Now, when the first tripping plate 41 rotates counterclockwise in FIG. 2, the latching state between the locking portion 41 e and one end of the operation plate 43 (left end in FIG. 2) is released, and the operation plate 43 is connected to the link 44. It rotates counterclockwise in FIG. 2 about the lower shaft 44b. Therefore, the restriction of the cross bar 40 by the other end (the right end in FIG. 2) of the operation plate 43 is eliminated, and the cross bar 40 is rotated counterclockwise in FIG. 2 by the spring force of the coil spring 62, and the movable contacts 4A and 4B. Is returned to the open state, and the movable contacts 3A and 3B are separated from the fixed contacts 2A and 2B, respectively. That is, when an overload current flows through the main circuit, the switching mechanism 5 is released by the thermal release device, and the main contact can be forcibly opened to protect the load.
[0101]
Thereafter, the bimetals 45 and 46 return to their original state due to the interruption of the electric circuit, and the first tripping plate 41 returns to its original position by the urging of the torsion spring 81, and at the same time, the opposing portion 42a of the second tripping plate 42. The receiving portion 41f pushes and moves the second tripping plate 42 back. Further, the handle 6 is rotated in the opening direction (clockwise in FIG. 2) by the bias of the torsion spring 36.
[0102]
Further, in the above-mentioned input state, when an abnormal large current such as a short-circuit current (a large short-circuit current due to a circuit short-circuit) flows through the current-carrying conductor 80 of one pole, an electromagnetic attractive force is generated in the fixed core 57 and the movable core 58 is Suction and rock. As a result, as shown in FIG. 12, the tip of the movable iron core 58 pushes up the receiving portion 42c of the second tripping plate 42 to rotate the second tripping plate 42 counterclockwise. When the second trip plate 42 rotates counterclockwise in the same manner as when an overload current flows, the opposing portion 42a of the second trip plate 42 moves the receiving portion 41f of the first trip plate 41 leftward. Push to turn clockwise. When the first tripping plate 41 rotates clockwise, the latched state between the locking portion 41e and one end (right end) of the operating plate 43 is released, and the operating plate 43 is centered on the lower shaft 44b of the link 44. Will rotate clockwise. Therefore, there is no restriction of the cross bar 40 by the other end (left end) of the operating plate 43, the cross bar 40 is rotated clockwise by the spring force of the coil spring 62, and the movable contacts 4A and 4B are returned to the open state. The movable contacts 3A and 3B are separated from the fixed contacts 2A and 2B, respectively. That is, when an abnormal large current such as a short-circuit current flows through one pole (the fixed contact 2B and the movable contact 3B) of the main circuit, the opening / closing mechanism 5 is released by the second electromagnetic release device 47B. The contact can be forcibly opened.
[0103]
Thereafter, when the electromagnetic attraction force is no longer generated in the fixed iron core 57 due to the interruption of the electric circuit, the movable iron core 58 returns to the original state by the spring force of the leaf spring 59, and the first tripping plate 41 is restored to the original state by the bias of the torsion spring 81. At the same time, the receiving portion 41f of the second tripping plate 42 is pushed and moved to return the second tripping plate 42 to the original position. Further, the handle 6 is rotated in the opening direction (counterclockwise) by the bias of the torsion spring 36. Note that the operating current of the second electromagnetic release device 47B is set to a value larger than the cord short-circuit current, and operates as described above due to a short-circuit current due to a circuit short-circuit (see solid line C in the figure). It does not operate with current (see the solid line b in the figure).
[0104]
Further, when a leakage current such as a ground fault current flows in the input state, the leakage protection circuit 51 energizes the coil 68 to generate an electromagnetic attracting force on the fixed core 57 to attract and swing the movable core 58. . As in this case, as shown in FIG. 12, the tip of the movable iron core 58 pushes the receiving portion 42c of the second tripping plate 42 to rotate the second tripping plate 42 counterclockwise, as in the case where a short-circuit current flows. At the same time, the first tripping plate 41 is rotated clockwise to return the movable contacts 4A and 4B to the open state, thereby separating the movable contacts 3A and 3B from the fixed contacts 2A and 2B, respectively. That is, when a leakage current flows in the main circuit, the third electromagnetic release device 48 releases the opening / closing mechanism 5 to forcibly open the main contact to protect the ground fault.
[0105]
On the other hand, when the cord short circuit current or the short circuit current flows to the bimetal 45 of the other pole in the above-mentioned input state, the opening / closing mechanism 5 is released by the first electromagnetic release device 47A to forcibly open the main contact. That is, the operating current of the first electromagnetic release device 47A is set to a value larger than the overflow (see the solid line a in FIG. 15A) and smaller than the cord short-circuit current (the level of FIG. B) Operation is made even with a cord short-circuit current having a level lower than that of the short-circuit current.
[0106]
Thus, when a cord short-circuit current or a short-circuit current flows through the bimetal 45 that is a current-carrying conductor, first of all, due to the electromagnetic attractive force generated between the magnetic pole surface of the side piece 60b of the second iron core 60 and the first iron core 61, 2 The iron core 60 moves in a direction approaching the first iron core 61 against the spring force of the return spring 64, and further electromagnetically attracts after the second iron core 60 moves to a position where the side piece 60a contacts the end face of the groove 31h. The first iron core 61 is sucked and swung in the direction approaching the second iron core 60 by the force. As a result, as shown in FIG. 13, the first tripping plate 41, to which the first iron core 61 is attached, rotates counterclockwise in FIG. 13, and one end (left end) of the locking portion 41e and the operating plate 43. Thus, the actuating plate 43 rotates counterclockwise around the lower shaft 44b of the link 44. Therefore, the restriction of the cross bar 40 by the other end (right end) of the operating plate 43 is eliminated, and the cross bar 40 is rotated counterclockwise by the spring force of the coil spring 62 to return the movable contacts 4A and 4B to the open state. The movable contacts 3A and 3B are separated from the fixed contacts 2A and 2B, respectively.
[0107]
FIG. 15 shows the overflow of the bimetal 45 (solid line a in FIG. 15A), the cord short circuit current (solid line b in FIG. 15A), the short circuit current (solid line c in FIG. 15A), and the motor and inverter. When an inrush current that flows instantaneously in a much shorter time than overflow (when represented by the solid line d in Fig. 3 (a), hereinafter referred to as "instantaneous inrush current") The mode that the 1st iron core 61 and the 2nd iron core 60 move is represented. Further, the current threshold when the second iron core 60 starts moving against the spring force of the return spring 64 is set to level C in FIG. Here, the horizontal axis in FIGS. 15B to 15E indicates the elapsed time [seconds] from the time when the current exceeding the rating as described above starts flowing, and the vertical axes indicate the first iron core 61 and the second iron core. 60 positions are shown. However, the positions (initial positions) of the first iron core 61 and the second iron core 60 when only the current below the rating flows are P1 for the first iron core 61 and zero on the vertical axis for the second iron core 60. The position when the second iron core 60 moves and approaches the first iron core 61 (movement completion position) is defined as P2. FIG. 16 shows the relationship between the electromagnetic attractive force (load during operation) [N] and the distance [mm] between the first iron core 61 and the second iron core 60, and the electromagnetic attractive force is the threshold value X1. Exceeds the spring force of the return spring 64, the second iron core 60 starts moving toward the first iron core 61, and the second iron core 60 moves when the electromagnetic attraction force reaches the threshold value X2. The completion position P2 is reached. When the electromagnetic attraction force further increases from that point and exceeds the threshold value X3, the electromagnetic attraction force wins over the sum of the spring force of the torsion spring 81 and the load applied to the first trip plate 41 by the actuating plate 43 in the latched state, This time, the first iron core 61 starts to move toward the second iron core 60, and when the electromagnetic attractive force reaches the threshold value X4, the latching portion 41e of the first tripping plate 41 and one end of the operating plate 43 are latched. The state is released and the tripping operation is performed. The operating current (level B) of the first electromagnetic release device 47A is a value based on the distance from the first iron core 61 when the second iron core 60 is at the movement completion position (current that generates an electromagnetic attraction force with a threshold value X4). Value). Further, level A in FIG. 15A is a current level at which the second iron core 60 starts to move against the spring force of the return spring 64, and level D is an operation when the second iron core 60 is in the initial position. Current is shown.
[0108]
Thus, when overflow occurs in the bimetal 45, as shown in FIG. 15C, the second iron core 60 starts moving from the initial position from the time when the overflow exceeds level C, and the movement completion position P2 Although the first iron core 61 remains at the initial position P1 without starting to move because the overflow does not exceed level A, the main contact is forcibly opened even if the overflow occurs. There is no.
[0109]
On the other hand, when the cord short-circuit current flows through the bimetal 45, the second iron core 60 starts moving from the initial position from the time when the cord short-circuit current exceeds the level C as shown in FIG. After that, the first iron core 61 starts moving from the initial position P1 when the cord short-circuit current exceeds the level A, approaches the second iron core 60, the cord short-circuit current exceeds the level B, and the second iron core. When the distance between 60 and the first iron core 61 becomes a predetermined value or less, the latching state between the locking portion 41e of the first tripping plate 41 and one end of the operation plate 43 is released, and the tripping operation is performed. The main contacts (fixed contact 2A and movable contact 3A) are forcibly opened. Further, as shown in FIG. 15E, the case where the short-circuit current flows through the bimetal 45 is the same as the case where the short-circuit current flows, but the rise time of the short-circuit current is shorter than the rise time of the short-circuit current. The time from when the current starts to flow until it reaches the operating current (level A) is shortened, and the tripping operation is also started earlier.
[0110]
However, when an instantaneous inrush current as shown by a solid line d in FIG. 15A flows through the bimetal 45, the instantaneous inrush current flows only for a very short time as shown in FIG. The inrush current stops flowing before the second iron core 60 that has started the movement reaches the movement completion position P2. Therefore, the distance between the first iron core 61 and the second iron core 60 does not fall below a predetermined value, and the main contact can be prevented from being forcibly opened (see FIG. 14).
[0111]
(Embodiment 2)
The present embodiment is characterized in that a return spring 64 that elastically biases the second iron core 60 in a direction away from the first iron core 61 is interposed between the second iron core 60 and the container body 1. The configuration is the same as in the first embodiment. Therefore, the same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted. Only the configuration that is a feature of the present embodiment will be described.
[0112]
As shown in FIG. 17, a cylindrical spring seat 60c protrudes from the tip surface of the shorter side piece 60a of the second iron core 60, and one side of the concave groove 31h facing the tip surface of the side piece 60a (see FIG. A cylindrical spring seat 31i protrudes from the end face on the right side in FIG. 17, and both ends of the return spring 64 are extrapolated to the two spring seats 60c and 31i, respectively, and the second iron core 60 and the body 1 A return spring 64 is interposed between the partition wall member 31 and the partition wall member 31.
[0113]
Thus, if no current exceeding the rating flows through the bimetal 45, the second iron core 60 is urged away from the first iron core 61 by the spring force of the return spring 64 as shown in FIG. The partition member 31 is held in contact with the peripheral wall 31b. When the current flowing through the bimetal 45 exceeds the level C, the second iron core 60 starts to move toward the first iron core 61 against the spring force of the return spring 64 as shown in FIG. The movement of the second iron core 60 stops at the compression limit of the return spring 64. If the current flowing through the bimetal 45 further increases and exceeds the above level A, the first iron core 61 starts moving toward the second iron core 60, and when the level B is exceeded, as shown in FIG. Thus, when the distance between the first iron core 61 and the second iron core 60 becomes equal to or less than a predetermined value, the latching state between the locking portion 41e of the first tripping plate 41 and one end of the operation plate 43 is released and the tripping is performed. The operation is performed and the main contacts (the fixed contact 2A and the movable contact 3A) are forcibly opened.
[0114]
As described above, in the present embodiment, the return core 64 that elastically biases the second iron core 60 in a direction away from the first iron core 61 is interposed between the second iron core 60 and the body 1. Since the bimetal 45 and the first iron core 61 can be disposed after the 60 and the return spring 64 are disposed on the partition wall member 31, the assembling work is facilitated.
[0115]
(Embodiment 3)
In this embodiment, the second iron core 60 in the first and second embodiments is a fixed iron core fixed so as not to move with respect to the partition member 31, and the first iron core (movable iron core) 61 is attached to the first tripping plate 41. It is provided so as to be movable in the direction of contact with and away from the fixed iron core 60, and is movable with a force weaker than the force (the spring force of the torsion spring 81) for urging the first trip plate 41 in the direction of restricting the movement of the operation plate 43. There is a feature in that the iron core 61 is urged away from the fixed iron core 60. Thus, since the configuration other than the first electromagnetic release device 47A is the same as that of the first or second embodiment, the same components are denoted by the same reference numerals and the description thereof is omitted.
[0116]
The first electromagnetic release device 47A in the present embodiment includes a pair of attachment members 66 provided with a flange 66b at the tip of a rod-like main portion 66a, and penetrates the movable iron core 61 on the front and back sides from the diameter of the main portion 66a. The main portion 66a of the mounting member 66 is inserted into a pair of through holes 61a having a diameter larger than that of the flange portion 66b, and the rear end of the main portion 66a inserted into the through hole 61a is first tripped. The upper end of the protruding portion 41b of the plate 41 is fixed by press-fitting into a pair of press-fitting holes 41i formed on the surface opposite to the engaging portion 41e, and a return spring 64 made of a compression coil spring is fixed to the main portion of the mounting member 66. It is configured to be inserted between the portion 66 a and disposed between the flange 66 b and the movable iron core 61. That is, the movable iron core 61 is movably attached to the first tripping plate 41 by the attachment member 66 in a direction in which the movable iron core 61 contacts and separates from the fixed iron core 60, and moves away from the fixed iron core 60 by the spring force of the return spring 64. It is elastically biased. The spring force of the return spring 64 is set to be weaker than the spring force of the torsion spring 81 that urges the first trip plate 41 in a direction that restricts the movement of the operation plate 43.
[0117]
Thus, when the cord short-circuit current or the short-circuit current flows through the bimetal 45, the movable iron core 61 is first restored by the electromagnetic attractive force generated between the magnetic pole surface of the side piece 60b of the fixed iron core 60 and the movable iron core 61. The movable core moves against the spring force of 64 and moves toward the flange 66b of the mounting member 66, moves to the compression limit of the return spring 64, and further moves against the spring force of the torsion spring 81 by electromagnetic attraction force. The first tripping plate 41 to which the movable iron core 61 is attached is rotated counterclockwise in FIG. 20 by sucking and swinging 61 in a direction approaching the fixed iron core 60.
[0118]
Next, the operation of the present embodiment will be described with reference to FIGS. However, the operation when manually switching from the open state to the open state or from the open state to the open state, and the operation when the main contact is forcibly opened by the second and third electromagnetic release devices 47B and 48 and the thermal release device Since this is the same as that of the first embodiment, the description thereof will be omitted, and only the operation when the main contact is forcibly opened by the first electromagnetic release device 47A, which is a feature of the present embodiment, will be described.
[0119]
In the closed state shown in FIG. 20, when a cord short-circuit current or a short-circuit current flows to the bimetal 45, the opening / closing mechanism 5 is released by the first electromagnetic release device 47A to forcibly open the main contact. That is, as in the first embodiment, the operating current of the first electromagnetic release device 47A is set to a value that is larger than the overflow (see the solid line a in FIG. 25A) and smaller than the cord short circuit current (same as above). Level B) in the figure (a) operates even with a cord short-circuit current having a lower level than the short-circuit current.
[0120]
Thus, when a cord short-circuit current or a short-circuit current flows through the bimetal 45, the movable iron core 61 is first returned to the return spring 64 by electromagnetic attraction generated between the magnetic pole surface of the side piece 60 b of the fixed iron core 60 and the movable iron core 61. After moving to the flange 66b of the mounting member 66 against the spring force of the mounting member 66 and moving to the compression limit of the return spring 64, the movable iron core 61 is further resisted against the spring force of the torsion spring 81 by electromagnetic attraction force. Is sucked and swung in a direction approaching the fixed iron core 60. Accordingly, as shown in FIG. 23, the first tripping plate 41 to which the movable iron core 61 is attached rotates counterclockwise in FIG. 23, and the locking portion 41e and one end (left end) of the operation plate 43 Thus, the actuating plate 43 is rotated counterclockwise around the lower shaft 44b of the link 44. Therefore, the restriction of the cross bar 40 by the other end (right end) of the operating plate 43 is eliminated, and the cross bar 40 is rotated counterclockwise by the spring force of the coil spring 62 to return the movable contacts 4A and 4B to the open state. The movable contacts 3A and 3B are separated from the fixed contacts 2A and 2B, respectively.
[0121]
FIG. 25 shows the overflow of the bimetal 45 (solid line a in FIG. 25A), the cord short circuit current (solid line b in FIG. 15A), the short circuit current (solid line c in FIG. 25A), and the instantaneous inrush current. The state in which the movable iron core 61 and the fixed iron core 60 move when the flow (the solid line d in FIG. 10A) flows is shown. The threshold value of the current when the movable iron core 61 starts moving with respect to the first tripping plate 41 against the spring force of the return spring 64 is set to level C in FIG. Here, the horizontal axis in FIGS. 25 (b) to 25 (e) represents the elapsed time [seconds] from the point when the current exceeding the rating as described above starts flowing, and the vertical axis represents the movable core 61 and the fixed core 60. Indicates the position. However, the position (initial position) of the movable iron core 61 when the position P3 of the fixed iron core 60 and a current less than the rated current flows is the zero position on the vertical axis, and the movable iron core 61 is in relation to the first tripping plate 41. A position (moving completion position) when moving and closest to the flange 66b of the mounting member 66 is defined as P4. FIG. 26 shows the relationship between the electromagnetic attractive force [N] acting between the movable iron core 61 and the fixed iron core 60 and the distance [mm] between them, and when the electromagnetic attractive force exceeds the threshold value Y1, the return spring 64 The movable iron core 61 starts moving when the electromagnetic attraction force wins over the spring force and the movable iron core 61 starts moving toward the flange 66b with respect to the first tripping plate 41, and the electromagnetic attraction force reaches the threshold value Y2. The position P4 is reached. When the electromagnetic attraction force further increases from this and exceeds the threshold value Y3, the electromagnetic attraction force wins over the sum of the spring force of the torsion spring 81 and the load applied to the first trip plate 41 by the actuating plate 43 in the latched state, When the movable iron core 61 starts to move toward the fixed iron core 60 and the electromagnetic attractive force reaches the threshold value Y4, the latched state between the locking portion 41e of the first tripping plate 41 and one end of the operating plate 43 is released. The tripping operation is performed. The operating current (level B) of the first electromagnetic release device 47A is a value based on the distance from the fixed iron core 60 when the movable iron core 61 is at the movement completion position P4 (the current value that generates the electromagnetic attractive force of the threshold Y4). ). Further, level A in FIG. 25A is a current level at which the movable iron core 61 starts moving against the spring force of the return spring 64, and level D is an operating current when the movable iron core 61 is in the initial position. Show.
[0122]
Thus, when overflow occurs in the bimetal 45, the movable iron core 61 starts moving from the initial position to the movement completion position P3 from the time when the overflow exceeds level C as shown in FIG. 25 (c). Although moving, since the overflow does not exceed level A, the movable iron core 61 does not move further from the movement completion position P3 toward the fixed iron core 60, so that the main contact is forcibly opened even if overflow occurs. There is no.
[0123]
On the other hand, when the cord short-circuit current flows through the bimetal 45, the movable iron core 61 starts moving from the initial position to the movement completion position P3 from the time when the cord short-circuit current exceeds the level C as shown in FIG. After that, the movable iron core 61 further moves from the movement completion position P3 toward the fixed iron core 60 when the cord short-circuit current exceeds the level A, and the cord short-circuit current exceeds the level B and the fixed iron core 60. When the distance from the movable iron core 61 becomes a predetermined value or less, the latching state between the locking portion 41e of the first tripping plate 41 and one end of the operation plate 43 is released, and the tripping operation is performed to perform the main contact ( The fixed contact 2A and the movable contact 3A) are forcibly opened. Further, as shown in FIG. 25 (e), the case where the short circuit current flows through the bimetal 45 is the same as the case where the short circuit current flows, but the rise time of the short circuit current is shorter than the rise time of the short circuit current. The time from when the current starts to flow until it reaches the operating current (level A) is shortened, and the tripping operation is also started earlier.
[0124]
However, when an instantaneous inrush current as shown by a solid line D in FIG. 25A flows through the bimetal 45, the instantaneous inrush current flows only for a very short time as shown in FIG. The inrush current stops flowing before the movable iron core 61 that has started has reached the movement completion position P4. Therefore, the distance between the movable iron core 61 and the fixed iron core 60 does not fall below a predetermined value, and the main contact can be prevented from being forcibly opened (see FIG. 24).
[0125]
Here, in the first electromagnetic release device 47A according to the present embodiment, the return spring 64 that is extrapolated to the main portion 66a of the mounting member 66 is disposed between the flange portion 66b and the movable iron core 61. Is supported by the main portion 66a of the mounting member 66 between the flange portion 66b and the movable iron core 61, so that the return spring 64 can be prevented from falling off or buckling. Further, since the plurality of mounting members 66 are provided in the first electromagnetic release device 47A, and the plurality of through holes 61a through which the main portions 66a of the respective mounting members 66 are inserted are provided in the movable iron core 61, the first tripping is performed. It is possible to prevent the displacement of the movable iron core 61 with respect to the swinging portion (projecting portion 41b) of the plate 41 and stabilize the characteristics. Further, since the press-fitting hole 41 i for press-fitting the rear end of the main portion 66 a of the mounting member 66 is provided in the swinging portion of the first tripping plate 41, the return spring 64 and the movable iron core 61 can be easily replaced. There is an advantage that can be.
[0126]
【The invention's effect】
The invention according to claim 1 is a device housing a main circuit, a handle that is at least partially exposed from the device, and an opening / closing mechanism that opens and closes a main contact of the main circuit according to an operation of the handle. An electromagnetic release device that releases the switching mechanism to forcibly open the main contact when a short-circuit current flows in the main circuit, the electromagnetic release device having a first iron core and a second iron core, The first iron core is slidably connected to and away from the second iron core with a current-carrying conductor forming a circuit in between, and the first iron core is urged away from the second iron core, and the second iron core pushes the first iron core. In a circuit breaker that releases the opening and closing mechanism when the distance between the first iron core and the second iron core is less than a predetermined value by suction, the second iron core is movably arranged in the direction of contact with and away from the first iron core. It is weaker than the force that urges the first iron core away from the second iron core Since the second iron core is energized in the direction away from the first iron core, when a current exceeding the rating flows through the current-carrying conductor, the first iron core moves first in the direction in contact with the first iron core and then the first iron core. Moves in a direction in contact with the second iron core, so that when the short-circuit current or the cord short-circuit current flows, the first and second iron cores move in directions in which they contact each other by electromagnetic attraction force, and the main contact is forcibly opened. However, since the inrush current that flows instantaneously when the load is started does not flow before the first iron core starts to move, the distance between the first iron core and the second iron core does not fall below a predetermined value, and the main contact is incorrect. This has the effect of preventing forced opening.
[0127]
In the invention of claim 2, in the invention of claim 1, a compression spring that elastically biases the second iron core in a direction away from the first iron core is interposed between the second iron core and the conducting conductor. Since it becomes easy to contact | abut to the center position of a 2nd iron core, there exists an effect that a 2nd iron core can be moved smoothly.
[0128]
According to a third aspect of the present invention, in the second aspect of the invention, the temperature of the overload current is fixed when the conductive conductor made of bimetal is fixed at one end and the other end is freely swingable, and an overload current flows through the conductive conductor. Equipped with a thermal release device that releases the open / close mechanism and forcibly opens the main contact by swinging the other end of the current-carrying conductor as it rises, and compresses it to a position closer to one end that is fixed from the center of the current-carrying conductor Since the spring is interposed, there is an effect that it is possible to prevent the displacement and dropout of the compression spring by suppressing the fluctuation of the distance between the compression spring and the second iron core when the other end of the conducting conductor swings.
[0129]
According to a fourth aspect of the present invention, in the first aspect of the invention, a compression spring that elastically biases the second iron core in a direction away from the first iron core is interposed between the second iron core and the body. In addition, since the current-carrying conductor and the first iron core can be disposed after the compression spring is disposed in the container, the assembly work can be facilitated.
[0130]
According to a fifth aspect of the present invention, in any of the first to fourth aspects of the present invention, the main contact is latched to be closed in a closed state, and the main contact is brought into an open state. The opening / closing mechanism includes a tripping member that restricts the movement of the latch member to be transferred and that releases the restriction when the distance between the first iron core and the second iron core of the electromagnetic release device falls below a predetermined value. Since the first iron core is attached to the swinging part of the tripping member, the electromagnetic release device does not require a member for transmitting the movement of the first iron core to the tripping member, and the number of parts can be reduced and the first iron core There is an effect that the size can be reduced by reducing the distance from the tripping member.
[0131]
The invention according to claim 6 is a container housing the main circuit, a handle that is at least partially exposed from the container, and an opening / closing mechanism that opens and closes the main contact of the main circuit according to the operation of the handle. An electromagnetic release device that releases the open / close mechanism and forcibly opens the main contact when a short-circuit current flows in the main circuit, the open / close mechanism includes a latch member that latches the main contact in a closed state; When a short-circuit current flows to the main circuit when it is energized in a direction that regulates the movement of the latch member while restricting the movement of the latch member that is swingably arranged in the body and shifts the main contact to the open state And a tripping member that is swung in a direction to release the restriction by the electromagnetic release device, and the electromagnetic release device is movable in a direction in which the fixed iron core is in contact with and separated from the swinging portion of the tripping member. Form the main circuit with the movable core It has a fixed core fixed to the body in such a way that the electric conductor is sandwiched between the movable core and the movable core is fixed with a force weaker than the force that urges the tripping member in the direction to restrict the movement of the latch member. Since the fixed iron core attracts the movable iron core and the distance between the movable iron core and the fixed iron core falls below a predetermined value, the restriction by the tripping member is released, so When a current exceeding the rating flows, the movable iron core first trips and moves in the direction of contact with the fixed iron core relative to the swinging part of the member, and then the movable iron core contacts the fixed iron core while swinging the tripping member. Therefore, when a short-circuit current or cord short-circuit current flows, the movable iron core moves in a direction that contacts the fixed iron core while swinging the tripping member, and the main contact is forcibly opened. Inrush current that flows instantaneously at the time of Since the core does not flow before starting to move while swinging the tripping member, the distance between the movable iron core and the fixed iron core does not fall below a predetermined value, and the main contact can be prevented from being forcibly opened. There is an effect.
[0132]
The invention of claim 7 is the invention of claim 6, wherein the electromagnetic release device includes an attachment member having a flange at the tip of the rod-like main portion, and penetrates the movable iron core on the front and back and is larger than the diameter of the main portion. The main portion of the mounting member is inserted into the through hole having a diameter smaller than the diameter of the flange portion and the rear end of the main portion inserted into the through hole is tripped and fixed to the swinging portion of the member. Since the compression coil spring extrapolated to is disposed between the collar and the movable iron core, the compression coil spring is supported by the main part of the mounting member between the collar and the movable iron core. It has the effect of preventing falling off and buckling.
[0133]
The invention of claim 8 provides the tripping device according to the invention of claim 7, wherein the electromagnetic release device includes a plurality of mounting members and a plurality of through holes through which the main portions of the mounting members are inserted in the movable iron core. There is an effect that the position of the movable iron core relative to the rocking part of the member can be prevented and the characteristics can be stabilized.
[0134]
The invention according to claim 9 is the invention according to claim 7 or 8, wherein the press-fitting hole into which the rear end of the main part of the mounting member is detachably inserted is provided in the swinging portion of the tripping member. There is an effect that can be easily exchanged.
[Brief description of the drawings]
FIG. 1 is an exploded perspective view showing a first embodiment.
FIG. 2 is a side view showing the input state, with the first side case removed.
FIG. 3 is a side view showing the opened state, with the first side case removed.
FIG. 4 is a rear sectional view of the above.
FIG. 5 is an exploded perspective view of the first electromagnetic release device and the thermal release device in the same as above.
FIG. 6 is an exploded perspective view of the second and third electromagnetic release devices.
FIG. 7 is a perspective view of the second and third electromagnetic release devices in the same as above.
FIG. 8 is a circuit diagram of a leakage protection circuit and a test circuit in the same as above.
FIG. 9 is an exploded perspective view of the structural portion of the zero-phase current transformer and the first and second circuit boards in the same as above.
FIG. 10 is a perspective view of the structural portion of the zero-phase current transformer and the first and second circuit boards in the same as above.
FIG. 11 is a rear sectional view of the same.
FIG. 12 is a side view showing a state in which the second electromagnetic release device has been operated from the input state, with the second side case removed.
FIG. 13 is a side view showing a state in which the first electromagnetic release device has been operated from the input state same as above, with the first side case removed.
FIG. 14 is a side view showing a state in which the second iron core of the first electromagnetic release device has moved from the throwing-up state, with the first side case removed.
FIGS. 15A to 15E are operation explanatory views of the first electromagnetic release device according to the embodiment.
FIG. 16 is an operation explanatory diagram of the first electromagnetic release device according to the above.
FIG. 17 is an exploded perspective view of the first electromagnetic release device and the thermal release device in the second embodiment.
FIGS. 18A to 18C are operation explanatory views of the first electromagnetic release device according to the embodiment.
FIG. 19 is an exploded perspective view of a first trip plate and a movable iron core according to the third embodiment.
FIG. 20 is a side view showing the input state, with the first side case removed.
FIG. 21 is a side view showing the opened state, with the first side case removed.
FIG. 22 is a side view showing the opened state, with the second side case removed.
FIG. 23 is a side view showing a state in which the first electromagnetic release device has been operated and the main contact has been opened from the input state, and the first side case has been removed.
FIG. 24 is a side view showing a state in which the movable iron core of the first electromagnetic release device has moved only with respect to the first tripping plate from the input state, and the first side case is removed.
FIGS. 25A to 25E are operation explanatory views of the first electromagnetic release device according to the embodiment;
FIG. 26 is a diagram for explaining the operation of the first electromagnetic release device according to the first embodiment.
FIGS. 27A to 27E are operation explanatory views of an electromagnetic release device in a conventional example.
[Explanation of symbols]
1 body
2A, 2B fixed contact
3A, 3B movable contact
5 Opening and closing mechanism
6 Handle
41 First trip plate
45 bimetal
47A First electromagnetic release device
60 Second iron core
61 1st iron core
64 Return spring
81 Torsion spring
