JP4203870B2

JP4203870B2 - Thermally responsive switch

Info

Publication number: JP4203870B2
Application number: JP27947098A
Authority: JP
Inventors: 岳男辻; 秀樹小関
Original assignee: Ubukata Industries Co Ltd
Current assignee: Ubukata Industries Co Ltd
Priority date: 1998-09-14
Filing date: 1998-09-14
Publication date: 2009-01-07
Anticipated expiration: 2018-09-14
Also published as: JP2000090790A

Description

【０００１】
【発明の属する技術分野】
本発明は熱応動スイッチに係るものであり、特にバイメタルのような熱応動板が通電電流の大きさにより受ける影響を少なくするようにし、実質的に周囲温度で動作するように構成された密閉形熱応動スイッチに関するものである。
【０００２】
【従来の技術】
従来、エアコン等の電動機には異常時の過熱や過電流からの保護のために各種の保護スイッチが使用されてきた。これら従来の保護スイッチは圧縮機内の過熱及び電動機の過電流に応動するように熱応動板に電動機の運転電流を流す構造とされており、周囲温度が異常に上昇した場合や電流値が増大した場合にこの熱応動板が反転することにより運転電流を遮断するものであった。
【０００３】
近時、電動機として細やかな制御が容易で且つ効率が良いことからインバータ制御の電動機が広く使用されるようになってきた。しかしながらこのインバータ制御の電動機では、従来使われてきた保護スイッチによる保護が極めて困難なものになっていた。つまり従来の電動機に於いては通常の運転電流はほぼ一定であるために、保護スイッチをその運転電流値では動作せずローターロック等の異常時の過電流に於いて動作するように設定していたのであるが、インバータ制御の電動機に於いては通常運転に於いても負荷に応じて運転電流を変化させるものであるために運転電流による熱応動板の発熱を利用することは逆に保護特性の的確性を欠くおそれがある。そこでインバータ制御の電動機の保護スイッチとしては熱応動板に実質的に運転電流を流さない熱応動スイッチが使用される。
【０００４】
従来この種の熱応動スイッチとしては数々の提案がなされているが、その多くは可動接点を駆動するための熱応動板を配置するために樹脂などの絶縁物による比較的大きな基台を必要とし、小型化を困難なものにしていた。例えばこの例として特公昭５６−８４５６号公報に記載された「サーモスイッチ」などがある。ここで記載されているスイッチは可動接点支持板上に設けられた可動接点を固定接点と接触−開離させるバイメタルを設け、このバイメタルには電流が直接流れないようにしたものである。またバイメタルは中央部に嵌挿孔が設けられており、絶縁基台上の支承凸起に嵌挿されている。このような構造の熱応動スイッチにおいては金属板であるバイメタルを絶縁保持するために絶縁基台のように比較的大きな絶縁物が必要とされる。
【０００５】
しかしながらスイッチ容器を気密な密閉容器にする場合においては、容器内部に絶縁物、特に大きなものを入れることは好ましくない。なぜならば絶縁物が樹脂である場合には密閉容器中で長期に亘って使用される場合などにおいては、樹脂から何らかのガスが発生する可能性があり、このガスが熱伝導性などを考慮して選定されたスイッチ内の封入ガスの組成を変化させてしまったり接点表面で化学変化を起こすなどして接点間の導電性を損なう可能性があるからである。またセラミックスを使用した場合などにおいてはガスの発生などの可能性は低くなるが金属部品との固定方法が難しく、またどちらの場合も熱容量が大きくなるので熱応動スイッチとしての応答性が低下するという問題がある。
【０００６】
例えば絶縁物の量を減らしたものとしては特開平１−３０２６２８号公報の「スイッチ装置」において金属製の収容部（容器）内にバイメタル式の熱応動スイッチが収納されているものが開示されている。このスイッチ装置は可動接点支持板の固定部にバイメタル板の一端を固定し、バイメタル板が所定の温度で反転することによりこの可動接点支持板を駆動するものである。
【０００７】
しかしながらこのスイッチ装置は固定接点などの導電部と金属製収容部との間に絶縁板を挟むように配置しているために組み付け時の作業性が悪いという問題がある。またこのスイッチ装置は金属製の容器と樹脂製の台を密着させているだけであって気密構造とされたものではない。例えばここで本公報中に従来例として示されたものの如く容器の開口部に樹脂などを充填する方法もあるが、このような簡易的な密閉構造においては長期的に封入ガスの組成を一定に保つことは不可能である。
【０００８】
完全な密閉構造のものとしては例えば特公平２−２１０８８号公報に示された「サーマルプロテクタ」がある。このプロテクタはガラス製の容器内に固定電極と可動電極を対向させ熱応動素子板により可動電極を駆動するものである。このプロテクタは可動電極として熱応動素子板と金属弾性片とを接点と共に可動端側で溶接固定し熱応動素子板の他端を反転時に保持する構造としている。そのため熱応動素子板が反転すると金属弾性片の偏倚力に抗して可動接点を固着した側を駆動し接点間を開離する。このサーマルプロテクタにおいてはバイメタルを溶接によって固定しているために組付前と組付後ではバイメタルの反転及び復帰温度が変化してしまうという問題があった。またこのサーマルプロテクタはガラス容器を使用することにより高い気密性を得ているが、例えば熱応動スイッチを密閉形電動圧縮機の密閉ハウジング内で使用する場合などにおいては、スイッチ容器の破損に関して取扱上特別な注意を必要とする。
【０００９】
また上述の「スイッチ装置」や「サーマルプロテクタ」においては、どちらも熱応動板を片持ち状態で使用しているために接点圧を高く設定しようとすると熱応動板に対する負担が大きくなり、熱応動板のみの時に付与された動作温度や復帰温度が接点圧を印加する事で変化してしまう不具合がある。
【００１０】
さらに特開昭５５−１４８３３１号公報の「熱保護スイッチ」においては熱応動板であるバイメタルスナップ板の中央に貫通された孔に挿通された接点によってバネスナップ板と固定されているものが示されている。この熱保護スイッチも熱応動板の反転時にはバネスナップ板による偏倚力に抗して可動接点を駆動するものであるが、熱応動板の中央に接点を配置しているために反転時の力は熱応動板の周縁部に分散するので、片持ち式のものと比較して熱応動板に対する負担を軽減することができる。
【００１１】
しかしこの熱保護スイッチはケーシング基体とケーシング蓋とを絶縁体を挟んでカシメなどの方法で固定しているものであり、本願の意図する厳密な意味での気密構造とする為の構成とは全く異なっている。またケーシング蓋の内面自体を固定接点としているために、ケーシングの僅かな変形によってもバイメタルにかかる力が変化してしまい、スイッチとしての動作温度や復帰温度が変化するという問題がある。
【００１２】
【発明が解決しようとする課題】
以上のように熱応動板に電流が流れない構造の熱応動スイッチにおいて従来提案されたものには、特に密閉型電動圧縮機の密閉ハウジング中などの高圧力中で使用するのに適したものが無く、そのため高い気密性と耐圧力性を有する容器を持ち熱応答性が良くなおかつ量産性の高い熱応動スイッチが求められていた。これを解決するために本出願人は特願平９−３２２２４４において「熱応動スイッチ」を出願している。しかしながらこの熱応動スイッチを小型にするためには、可動接点が取り付けられる可動板はバイメタルの動きに応じた動作ができるように非常に薄い金属板が使用される。可動板が薄いと、可動接点の取り付けや導電基部への溶接時やスイッチとして動作して可動板に曲げ応力がかけられた時などにおいて塑性変形による歪が発生する可能性があり、この場合には可動接点と固定接点との接触圧力や開離時の接点間距離が予定した範囲に収まらなくなるという問題があった。
【００１３】
【課題を解決するための手段】
本発明は特願平９−３２２２４４の改良に関するものである。
【００１４】
その特徴は、有底筒形の金属製容器と、貫通孔を設けられた金属板を有し、この金属板の貫通孔に導電性のリード端子ピンが電気的に絶縁された状態で気密に貫通固定されて蓋板を構成し、この蓋板を前記容器の開口端部に溶接によって気密に固定することにより気密容器を構成し、浅い皿状に絞り成形され且つほぼ中心に貫通孔を設けた熱応動板が所定の温度で反転及び復帰動作を行うことにより可動接点を固定接点に接触または開離し、前記リード端子ピンの前記気密容器内には固定接点部が設けられ、前記蓋板の金属板の前記気密容器内面には剛性の高い可動板支持体が固着され、可動板支持体にはしなやかな弾性を有した可動板の固定部となる一端が固着され、この可動板は板バネ状の導電性金属板からなり常に固定部とは逆の端部にあたる自由端側を可動板支持体側に押しつけるように偏倚力が与えられており、この可動板の自由端側には可動接点が固定され、さらに可動板の自由端側に固定された部材が熱応動板の貫通孔に挿通され熱応動板を遊嵌保持することによって可動板が熱応動板によって駆動されるように両者が連結された熱応動スイッチにおいて、前記可動板の自由端側には熱応動板に設けられた貫通孔よりも一回り直径の小さい貫通孔を設け、可動接点は一端を大径部、他端を小径部とし、この大径部と小径部の間には少なくとも熱応動板の貫通孔には通るが可動板の貫通孔には挿通できない径を有する熱応動板遊嵌部を設け、可動接点の小径部は前記熱応動板及び可動板の貫通孔に挿通されており、可動接点小径部の先端は変形され前記熱応動板遊嵌部の端面とで可動板を挟持固定し、熱応動板を可動接点の熱応動板遊嵌部で遊嵌保持したことにある。
【００１５】
さらに他の特徴は、可動板の自由端側には熱応動板に設けられた貫通孔よりも一回り直径の小さい貫通孔を設け、可動接点は接点部材と熱応動板遊嵌部材とからなり、この接点部材はその一端を接触部としており、熱応動板の貫通孔に挿通された熱応動板遊嵌部材の熱応動板遊嵌部先端に可動板の貫通孔を介して接点部材が溶接され、可動接点はその溶接部周辺で可動板を挟持固定していると共に熱応動板を熱応動板遊嵌部で遊嵌保持した熱応動スイッチにある。
【００１６】
また他の特徴は、可動接点と熱応動板遊嵌部材とを有し、可動接点は可動板に直接溶接固定され、熱応動板遊嵌部材は一端を大径部、他端を熱応動板の貫通孔に挿通する熱応動板遊嵌部とされ、熱応動板の貫通孔にはこの熱応動板遊嵌部が挿通されており、前記可動板の可動接点が溶接された面の裏面に熱応動板遊嵌部の先端が溶接されていることで熱応動板を可動板に連結し且つ遊嵌保持したことにある。
【００１７】
さらに本発明の熱応動スイッチは、可動板の自由端側には熱応動板の貫通孔よりも一回り直径の小さい貫通孔を設け、可動接点は一端を大径部、他端を小径部とし、この大径部と小径部の間には少なくとも熱応動板の貫通孔には通るが可動板の貫通孔には挿通できない径を有する熱応動板遊嵌部を設けられ、前記熱応動板及び可動板の貫通孔に挿通された可動接点はその熱応動板遊嵌部の端面に可動板を溶接固定されており、熱応動板をこの熱応動板遊嵌部で遊嵌保持したことを特徴とする。
【００１８】
また他の特徴は、可動接点の小径部は前記熱応動板及び可動板とともに貫通孔を有した補強板に挿通されており、可動接点が前記補強板を介して熱応動板遊嵌部の端面に可動板を固定していることにある。
【００１９】
さらに他の特徴は、可動板の固定部には固定部周囲の変形を防ぐためのあて板が可動板を可動板支持体とで挟むようにして溶着されていることにある。
【００２０】
また、熱応動スイッチの可動板が固着された可動板支持体と固定接点部との間に電気絶縁性の位置決め部材を挿入し、可動板支持体と固定接点部によって位置決め部材を挟持する事により、可動接点と固定接点との位置関係を規定することを特徴とする。
【００２１】
【発明の実施の形態】
次に本発明の熱応動スイッチの実施の形態について図面を参照して説明する。図１は本発明による熱応動スイッチの一実施例の縦断面図であり、図２はその横断面図、また図３は図１のＡ−Ａ断面矢視図である。さらに図４には本発明で使用される可動接点を、図５には容器を省略した熱応動スイッチの分解斜視図を示す。
【００２２】
この熱応動スイッチ１は筒の一方を閉止された有底円筒形状をしている金属製の容器２と、金属板３Ａとその貫通孔３Ｂに挿通されてガラスの如き絶縁性充填材４によって気密に固着されたリード端子ピン５から成る蓋板３を有している。容器２の開口端部は蓋板３の金属板３Ａの周縁部近傍に溶接等の方法で全周に亘って気密に固着され、両者は気密容器を構成している。気密容器の内部には熱伝導性などの点から選定された組成のガスを含んだ混合ガスなどが封入されており、この気密構造により長期に亘って組成を変化させることなく保つことができる。例えば実施例においては封入ガス中に熱伝導性の良いヘリウムガスを容積比において７５パーセントとして残る２５パーセントを窒素としているが、このヘリウムの含有量は熱伝導性の観点からは１０パーセント以上とするのが好ましく、またヘリウムの濃度が高すぎると接点開放状態での接点間耐電圧が低下するので９０パーセント以下とすることが好ましい。
【００２３】
蓋板３のリード端子ピン５の気密容器内部側の端部にはほぼ角柱状の固定接点部６が導電的に固着されている。なお本実施例においてはリード端子ピン５と別体の固定接点部６を設けたものを例に説明しているが、例えばリード端子ピン５を延長して後述の可動接点と接離可能な位置となるようにクランク形状に加工したり金属板３Ａに対して偏芯させて取り付けるなどして先端付近を固定接点部とする構造としてもよい。
【００２４】
蓋板３の金属板３Ａ上には剛性の高い可動板支持体７の一端が固着されている。この可動板支持体７はリード端子ピン５及び固定接点部６と必要な絶縁間隔を保つように中央に空間部７Ｂを有する金属板で構成されており、その固定側端部７Ａを曲げてＬ字型とされかつ全体的には固定接点部６とほぼ並行となるように設けられている。可動板支持体７にはしなやかな弾性板である可動板８の一端が２ヶ所の取付部８Ａで溶接などにより固着されている。この可動板８は板バネ状の導電性金属板からなり常に先端部８Ｂを可動板支持体側に押しつけるように偏倚力が与えられている。
【００２５】
この可動板８は後述の熱応動板の反転動作に従ってしなやかに動くこととスイッチを小型化することを両立させるために薄い金属板を使用している。そのために取付部８Ａで溶接するだけでは熱応動板の動作時に可動板の取付部８Ａ周辺に曲げ応力が集中することにより可動板８が塑性変形を生じて、上述の偏倚力が初期値より減少する可能性がある。そこでこれを防ぐために可動板８の溶接時に固定部、本実施例では取付部８Ａに可動板に比べて充分な強度の有るあて板１１を溶接などにより配置して取付部への曲げ応力の集中による変形を防ぎ、偏倚力の低下を抑える事が好ましい。
【００２６】
可動板８の先端部８Ｂ近傍には貫通孔８Ｃが設けられ、可動接点９がこの貫通孔にカシメ等によって固定されている。この可動接点９は加工前には図４（Ａ）に示すように一端を比較的大径の頭部９Ａとし、他端には円筒形の小径部９Ｂを設け、さらに頭部と小径部との間には頭部の直径よりも小さく小径部の直径よりも大きい径を有した熱応動板遊嵌部９Ｃを有している。この遊嵌部９Ｃの頭部端面９Ｄから遊嵌部端面９Ｅまでの厚みは後述する熱応動板１０の厚みよりも大きく設定されている。可動接点９はプレスなどによるカシメ作業により可動板８に固定されると共に、小径部９Ｂの先端が図４（Ｂ）等に示す如く成形され前記固定接点部６と接離する接触部９Ｆとされる。また可動接点９は固定接点部６との接触のために銀や銀合金等の接点材料から構成されているが、上述のように固着作業をカシメによって行う場合には頭部９Ａ及び遊嵌部９Ｃは小径部９Ｂよりも固い材質を使用した方が固着作業が容易になり好ましい。
【００２７】
熱応動板１０はバイメタルやトリメタルなどの熱変形金属板を浅い皿状に絞り形成したものであり、所定の第１の温度でその湾曲方向を急跳反転し、第２の温度で急跳復帰する。熱応動板１０の絞り中心近傍には可動接点９を挿通するための貫通孔１０Ａが穿たれており、さらに貫通孔１０Ａからは放射状にスリット１０Ｂが本実施例では４本設けられている。この貫通孔１０Ａは前述の可動板８に穿たれた貫通孔８Ｃよりも直径を大きくされている。またこれらのスリット１０Ｂで挟まれた部分は周囲の変位量を拡大するアーム１０Ｃとなるため、可動接点９の移動量をスリットの無いものよりも大きくすることができ、接点開離時の接点間距離を大きくできる。また見かけ上の接点間距離を同一にすれば可動接点８の固定接点部６側への偏倚量が増えることになりその結果、接点間の接触圧力を高くすることができる。
【００２８】
ここで可動接点９と可動板８及び熱応動板１０との組み付けについての説明をする。まず可動接点９の小径部９Ｂを熱応動板１０の貫通孔１０Ａに挿入する。ここで貫通孔１０Ａの内径は可動接点の遊嵌部９Ｃの外径よりも若干大きく設定されており、熱応動板１０は可動接点９の頭部端面９Ｄに当接する。次に小径部９Ｂを可動板８の貫通孔８Ｃに挿入する。この可動板の貫通孔８Ｃは熱応動版の貫通孔１０Ａよりも直径が一回り小さく、さらに可動接点の遊嵌部９Ｃの外径よりも小さくされているために遊嵌部の端面９Ｅに当接する。
【００２９】
本実施例においては可動接点９を可動板８に挿通した後に補強板としてワッシャ１２が装着されている。このワッシャ１２は可動接点のカシメ作業で変形しない程度に充分な厚さと強度を有した金属板であり、可動板の貫通孔８Ｃの周囲に当接してカシメ加工時に力の偏りなどから起こる可動板８の歪の発生が無いように補強する。このワッシャ１２は変形による歪が問題にならなければ必ずしも必要ではない。例えば可動板のカシメ部分の周囲にスリットを設けて変形による歪を逃がしたり、可動板自体を長くしてしなやかさを保ったままに厚みを増やすことでワッシャを省略することもできる。
【００３０】
補強板としてワッシャを有する本実施例では熱応動板１０、可動板８、ワッシャ１２に可動接点９が挿通された後に、プレスなどにより可動接点小径部９Ｂの先端部分を図４（Ｂ）等に示すような形に変形させて接触部９Ｆとする。接触部９Ｆは加工前より直径が広がるによりワッシャ１２を保持しこのワッシャ１２と可動接点の遊嵌部端面９Ｅとで可動板８の貫通孔８Ｃの周縁部を上下の面からカシメて固定する。ここで熱応動板１０は可動接点の遊嵌部９Ｃに位置しており、この遊嵌部９Ｃは前述したように厚みを熱応動板１０の厚みよりも厚くしてあり、さらに前記カシメ作業において実質的に変形しないようにされているので熱応動板１０はその運動が拘束されないように遊嵌保持される。そのため熱応動板１０の前述した所定の第１の温度で急跳反転する動作温度が組付けにより変化することはない。即ち、熱応動板１０の単体での動作温度と熱応動スイッチ１に組み込まれてからの動作温度とは一致する。そのため熱応動板に何らかの力が加わっている構造を持つ従来の熱応動スイッチにおいては熱応動板単体とスイッチ組み付け後とでは動作温度が変化するために必要とされていたスイッチ組み付け後の動作温度の確認または較正作業を、本発明の熱応動スイッチにおいては省略することができる。
【００３１】
また本発明は蓋板上にスイッチの回路を構成する部品をすべて配設してあるので、容器２を蓋板３に固着する前に各部の位置関係やスイッチ機構の動作を直接確認する事ができる。ここで可動接点９と固定接点部６との接触圧力並びに開放時の接点間距離の調整が必要な場合には、可動板支持体７または固定接点部６を曲げて、可動板支持体７の可動接点頭部端面９Ｄが当接する側の面と固定接点部６の接触面との位置関係を調整する。実施例の熱応動スイッチ１においてはこの調整作業は可動板支持体７の先端７Ｃを図１の上下方向に変位させる事によって行なわれる。また本実施例では図２及び図５に示すように可動板支持体７には蓋板との固定側端部７Ａ近傍に調整時に変形しやすいようにした幅細部７Ｄが設けられ、可動板の取付部８Ａより先端側を変形させることなく調整されるので、可動板８に予め付与された偏倚力を変化させること無く確実に調整作業を行なうことができる。
【００３２】
次に図１及び図６の動作状態を示す断面図を参照しながら熱応動スイッチ１の動作について説明する。通常は熱応動板１０の湾曲方向は図１に示すように可動板８の側に凸となっており、可動接点９は可動板８に付与されている偏倚力により固定接点部６に所定の接点圧力で当接されている。従って導電端子ピン５−固定接点部６−可動接点９−可動板８−可動板支持体７−蓋板３による電路が閉じられている。ここでこの熱応動スイッチを電動機に取り付けた場合を例に考えると、電路に電流が流れた場合にも熱応動板１０には電動機の運転電流は実質的に流れないので、運転電流による熱応動板１０の自己発熱による動作温度への影響は無視できる。また密閉容器内にヘリウムを含む熱伝導性の良い混合気体を封入してあることにより、平常時つまり周囲温度が低い間は上記電路での発熱は混合気体及び容器を介して外部に放出されるので電路の抵抗によるジュール熱により熱応動板１０が反転することもない。
【００３３】
ここで例えば電動機が何らかの原因で過熱状態になると熱応動スイッチ１の周囲温度が上昇し、この熱が容器及び混合ガスを介して密閉容器内部へと伝達される。これにより熱応動板１０が所定の第１の温度に達すると、熱応動板１０は急跳反転して図６に示すようにその湾曲方向を逆転させる。そのため熱応動板１０の両端部が可動板支持体７に直接若しくは可動板８を介して当接し、中央に位置する可動接点９を可動板８の偏倚力に抗して移動させ、接触部９Ｆを固定接点部６から開離させて電路を遮断する。
【００３４】
上述の実施例においては可動接点をカシメによって弾性板に固定しているが、カシメに換えて溶接によって固定しても良い。この例について図７を参照しながら説明する。なお前述の熱応動スイッチ１と同じ部分には同一の記号を付して詳細な説明は省略する。この熱応動スイッチ２１は可動接点２９を熱応動板１０と可動板８に挿通した後に、可動接点２９と可動板８とを溶接固定している。この可動接点２９は前述の可動接点９と同様に一端を比較的大径の頭部２９とし、他端を円筒形の小径部２９Ｂとし、さらに頭部と小径部との間には熱応動板遊嵌部２９Ｃを有している。この小径部２９Ｂの先端は前述の可動接点のようなプレス加工を必要としない、組付け前の時点ですでに接触部としての形状を整えられている。
【００３５】
可動板８よりも大きな貫通孔を穿たれた熱応動板１０は遊嵌部２９Ｃにまで挿通されており、可動板８は遊嵌部端面２９Ｅに当接する。ここで可動板１０に遊嵌部端面２９Ｅを溶接する事により両者は固定され、また遊嵌部２９Ｃの厚みを熱応動板１０よりも厚くしておくことにより熱応動板１０は動きを拘束されないように遊嵌保持される。例えばこの溶接時に起こる変形によって生ずる歪が可動板の動作に対して問題となる場合には、この溶接部にワッシャのような補強板をあてながら溶接するなどして変形を抑えても良いし、溶接部の周囲に変形歪を逃がすためのスリットを設けても良い。
【００３６】
また上述の接点構造の他にも、例えば図８（Ａ）及び（Ｂ）に示す構造とすることも可能である。図８（Ａ）のものにおいては、可動接点３１は接触部材３１Ａと熱応動板遊嵌部材３１Ｂに分割されており、両部材を可動板８と熱応動板１０それぞれの貫通孔８Ｃ及び１０Ａを介して溶接して一体となし、この溶接時に可動板８と熱応動板１０とを可動接点の両部材３１Ａ，３１Ｂで挟持固定している。さらに図８（Ｂ）の実施例においては貫通孔を持たない可動板４８を使用して、この可動板４８の図示下面に可動接点４１を溶接し、これに対する可動板の裏面、つまり図示上面には大径部と熱応動板遊嵌部を有した熱応動板遊嵌部材４２を可動接点４１にほぼ対応する位置に溶接している。なお図８（Ｂ）の実施例においては例えば熱応動板遊嵌部材と可動接点との溶接位置をオフセットさせることにより通電経路を短くし、通電経路上での発熱をより少なくすることができる。また図８（Ａ）及び（Ｂ）のどちらにおいても熱応動板１０は貫通孔１０Ａにおいてそれぞれ熱応動板遊嵌部で遊嵌保持されて可動板８の自由端と連結されていることは前述の各実施例と同様である。
【００３７】
本実施例においては接点間の接触圧力は前述した通り可動板支持体を変形させて調整されるが、これは言い換えれば可動板支持体と固定接点との位置関係を規定することである。しかし可動板支持体の変形時にはいわゆるスプリングバックなども生ずるためにこの調整作業はその点も見込んで行なう必要があり作業性が悪いものになっている。また調整作業をなくすためには各部品の寸法公差、及び組付時の寸法公差を非常に厳しく管理する必要があり困難を有する。
【００３８】
そこでこの調整作業を容易にするために改良したものを図９に示す。この実施例においても前述の各実施例と同様の部分には同一の番号を付して詳細な説明は省略する。この実施例の熱応動スイッチ５１は固定接点部５６が可動板支持体７に沿って延長されており、その先端部付近において両者の間には互いの距離を規定するための絶縁体でできた位置決め部材５２が配置されている。次にこの構成による調整作業について説明する。実施例では固定接点部５６と可動板支持体７は、接点間の接触圧力が高くなるように予め互いの先端部を適正値より接近させて蓋板上に組付けられる。そしてどちらかの部材を変形させる代りに、この両部材の間に所定の厚みを有した位置決め部材５２が挟み込まれる。
【００３９】
実施例では位置決め部材５２は図に示すように挿入方向に対して楔形をしており、また図面手前から奥にむけて両端が可動板支持体７にさしわたされている。このように固定接点部５６と可動板支持体７との間に挿入された位置決め部材５２は、その両端部は図示上面が可動板支持体７の先端部７Ｃ近傍に当接し、中央部は図示下面が固定接点部５６の先端部近傍に当接する。位置決め部材は固定接点部と可動板支持体両部材とで挟持されるが、両部材のいずれかに戻り止めを設けることでより確実に保持される。このように位置決め部材を使用する事により、適正値より狭かった両部材の間隙は所定の位置関係にまで広げられる。こうして本実施例によれば固定接点と可動板支持体との間に位置決め部材５２を挿入配置するだけで調整作業は完了し、大幅にその作業を簡略化できる。
【００４０】
ここまでに述べた実施例においては容器として一方が閉塞された円筒形をしたものを使用しているが、この形は円筒形に限らず例えば図１０に示す熱応動スイッチ６１の容器６２のように断面形状が楕円形など円形以外の筒形容器であってもよい。以下、この熱応動スイッチ６１について説明するが前述の熱応動スイッチ１と同じ部分には同一の記号を付して詳細な説明は省略する。この熱応動スイッチ６１では容器６２の断面形状を楕円形としたことにより、その開口部に当接し固着される蓋板６３の金属板６３Ａも楕円形としている。また可動板支持体６７は金属板６３と固着される固定側端部６７Ａが容器６２の内周面に沿って高さが抑えられている。これらの点を除いてはその動作も含めて前述の熱応動スイッチ１と同様である。
【００４１】
このように容器の断面形状を楕円形とする事により、容器６２と熱応動板１０との距離が前述の円形断面のものよりも近くなるので、周囲の温度変化に対する熱応動板１０の熱応答性が良くなる。また発熱要素への取り付けが行ないやすくなると共に、密閉容器を構成した後も容器の形状から熱応動板の向きを知ることができるので発熱要素に対して熱応動板が対面するように取り付けることが容易になり熱応答性をさらに良くすることができる。
【００４２】
なお上述の各実施例の説明において可動板及び熱応動板の貫通孔、並びにこれらの貫通孔に挿通される可動接点の部分に関して、円形であると想定して説明したが、例えば円形の他に楕円や多角形に置き換え、直径と表現した部分を大きさや太さに置き換えても同等の効果を表すことは云うまでもない。
【００４３】
【発明の効果】
本発明の熱応動スイッチによれば、インバータ制御の電動機のように負荷に応じて電流の変化するものに使用した場合においても、その運転電流の変化による動作条件への影響が少なく外部の温度変化に対して確実に対応できる直切りのスイッチを簡単な構造で提供することができる。
【００４４】
また可動板に対して組付け時に溶接やカシメの力が加わる部分に応力を分散させるためのあて板やワッシャを配置した事により、可動板に歪が発生しにくくなりより薄くしなやかな金属板を使用することができる。さらに固定接点と可動接点による電路形成時に両接点間の接点圧力の大小に関わらず熱応動板に外部からの力が加わらないようにしたことにより、熱応動スイッチの動作温度を予め熱応動板のみの時に付与された動作温度と一致させることができ、スイッチ完成後の動作温度の確認作業を省略することができる。
【００４５】
また気密容器を金属製の有底円筒形容器の開口部に蓋板を溶接などの方法により密着封止する構造のものとしたことにより、高い気密性と耐圧力性を容易に得ることができる。その結果、気密容器内の空間に所望の組成とされた気体を封入する事により、熱応動板と容器との間の熱伝導度、及び可動接点と固定接点部とが開放した状態における耐電圧を選定することができる。
【００４６】
さらに蓋板上にスイッチの回路を構成する部品をすべて配設したことにより、製造過程において気密容器を構成する前、つまり蓋板と容器とを固着する前に各部の位置関係やスイッチ機構の動作を直接確認する事ができ、組立作業がより容易になる。またこの製造過程において、所定の大きさの位置決め部材を固定接点と可動板支持体との間に挟持して固定接点と可動接点との位置関係を所定値とすることにより、煩雑な調整作業を省略することができる。
【図面の簡単な説明】
【図１】本発明の熱応動スイッチの一実施例の縦断面図
【図２】図１の熱応動スイッチの横断面図
【図３】図１の熱応動スイッチのＡ−Ａ断面矢視図
【図４】本発明の熱応動スイッチに使用される可動接点の他の実施例
【図５】図１の熱応動スイッチの容器２を除いた分解斜視図
【図６】図１の熱応動スイッチの動作状態を示す縦断面図
【図７】本発明の熱応動スイッチの他の実施例
【図８】図７の熱応動スイッチなどに使用される可動接点の他の実施例
【図９】本発明の他の実施例
【図１０】本発明の熱応動スイッチの他の実施例
【符号の説明】
１，２１，５１，６１：熱応動スイッチ
２，６２：容器
３，６３：蓋板
５：リード端子ピン
６：固定接点部
７，６７：可動板支持体
８：可動板
８Ｃ：貫通孔
９，２９，３１，４１：可動接点
９Ａ：頭部
９Ｂ：小径部
９Ｃ：遊嵌部
９Ｄ：頭部端面
９Ｅ：遊嵌部端面
９Ｆ：接触部
１０：熱応動板
１０Ａ：貫通孔
１０Ｂ：スリット
１０Ｃ：アーム
１１：あて板
１２：ワッシャ（補強板）
４２：熱応動板遊嵌部材
５２：位置決め部材[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a thermally responsive switch, and in particular, a thermally responsive plate such as a bimetal is less affected by the magnitude of the energized current and is configured to operate substantially at ambient temperature. The present invention relates to a thermally responsive switch.
[0002]
[Prior art]
Conventionally, various protection switches have been used for motors such as air conditioners for protection from overheating and overcurrent in the event of an abnormality. These conventional protection switches have a structure in which the operating current of the motor flows through the thermally actuated plate so as to respond to overheating in the compressor and overcurrent of the motor, and when the ambient temperature rises abnormally or the current value increases. In this case, the operating current was interrupted by the reversal of the thermally responsive plate.
[0003]
In recent years, inverter-controlled motors have been widely used because fine control is easy and efficient as a motor. However, in this inverter-controlled electric motor, it has been extremely difficult to protect with the conventionally used protective switch. In other words, in a conventional motor, the normal operating current is almost constant, so the protection switch is set not to operate at that operating current value, but to operate at an overcurrent when there is an abnormality such as a rotor lock. However, in an inverter-controlled motor, the operating current is changed according to the load even during normal operation. There is a risk of lack of accuracy. Therefore, as a protective switch for the inverter-controlled electric motor, a thermally responsive switch that does not substantially pass an operating current to the thermally responsive plate is used.
[0004]
Conventionally, many proposals have been made for this type of heat responsive switch, but many of them require a relatively large base made of an insulating material such as resin in order to place a heat responsive plate for driving the movable contact. It was difficult to downsize. For example, there is a “thermo switch” described in Japanese Patent Publication No. 56-8456. The switch described here is provided with a bimetal that contacts and separates the movable contact provided on the movable contact support plate from the fixed contact so that no current flows directly through the bimetal. The bimetal is provided with an insertion hole in the center, and is inserted into a support protrusion on the insulating base. In the heat responsive switch having such a structure, a relatively large insulator such as an insulating base is required in order to insulate and hold the bimetal which is a metal plate.
[0005]
However, when the switch container is an airtight sealed container, it is not preferable to put an insulator, particularly a large one, inside the container. This is because if the insulator is a resin, there is a possibility that some gas may be generated from the resin when it is used in a closed container for a long time. This is because there is a possibility that the conductivity between the contacts may be impaired by changing the composition of the sealed gas in the selected switch or causing a chemical change on the contact surface. In addition, when ceramics are used, the possibility of gas generation is reduced, but it is difficult to fix to metal parts. In both cases, the heat capacity increases, so the responsiveness as a thermally responsive switch decreases. There's a problem.
[0006]
For example, as an example in which the amount of the insulator is reduced, Japanese Patent Application Laid-Open No. 1-302628 discloses a “switch device” in which a bimetallic thermal response switch is housed in a metal housing (container). Yes. In this switch device, one end of a bimetal plate is fixed to a fixed portion of a movable contact support plate, and the movable contact support plate is driven when the bimetal plate is inverted at a predetermined temperature.
[0007]
However, since this switch device is arranged so that an insulating plate is sandwiched between a conductive portion such as a fixed contact and a metal housing portion, there is a problem that workability at the time of assembly is poor. Further, this switch device is not an airtight structure, but only a metal container and a resin base are brought into close contact with each other. For example, there is a method of filling the opening of the container with resin or the like as shown here as a conventional example in this publication, but in such a simple sealed structure, the composition of the sealed gas is kept constant over a long period of time. It is impossible to keep.
[0008]
An example of a completely sealed structure is a “thermal protector” disclosed in Japanese Patent Publication No. 2-21088. In this protector, a fixed electrode and a movable electrode are opposed to each other in a glass container, and the movable electrode is driven by a thermally responsive element plate. This protector has a structure in which a thermally responsive element plate and a metal elastic piece as a movable electrode are welded and fixed together with a contact on the movable end side, and the other end of the thermally responsive element plate is held during reversal. Therefore, when the thermally responsive element plate is reversed, the side to which the movable contact is fixed is driven against the biasing force of the metal elastic piece to separate the contacts. In this thermal protector, since the bimetal is fixed by welding, there is a problem that the inversion and return temperature of the bimetal changes before and after assembly. This thermal protector has a high airtightness due to the use of a glass container. For example, when a heat-responsive switch is used in a sealed housing of a hermetic electric compressor, Requires special attention.
[0009]
In the above-mentioned “switch device” and “thermal protector”, both use the thermal reaction plate in a cantilevered state, so if an attempt is made to set the contact pressure high, the burden on the thermal reaction plate increases, and the thermal There is a problem that the operating temperature and the return temperature applied when only the plate is changed by applying the contact pressure.
[0010]
Furthermore, the “thermal protection switch” disclosed in Japanese Patent Application Laid-Open No. 55-148331 shows one that is fixed to the spring snap plate by a contact point that is inserted through a hole penetrating through the center of a bimetal snap plate that is a thermally responsive plate. ing. This thermal protection switch also drives the movable contact against the biasing force of the spring snap plate when the thermal reaction plate is reversed, but the force at the time of reversal is because the contact is located in the center of the thermal response plate. Since it is dispersed in the peripheral portion of the thermal reaction plate, the burden on the thermal reaction plate can be reduced as compared with the cantilever type.
[0011]
However, this thermal protection switch is one in which the casing base and casing lid are fixed by a method such as caulking with an insulator sandwiched between them, and is completely different from the configuration for making an airtight structure in the strict sense intended by the present application. Is different. Further, since the inner surface of the casing lid itself is a fixed contact, the force applied to the bimetal changes even if the casing is slightly deformed, and there is a problem that the operating temperature and the return temperature as a switch change.
[0012]
[Problems to be solved by the invention]
As described above, conventionally proposed thermal responsive switches having a structure in which no current flows through the thermal responsive plate are particularly suitable for use in a high pressure such as in a sealed housing of a hermetic electric compressor. Therefore, there has been a demand for a thermally responsive switch having a container having high airtightness and pressure resistance, good thermal response and high mass productivity. In order to solve this problem, the present applicant has applied for a “thermally responsive switch” in Japanese Patent Application No. 9-322244. However, in order to reduce the size of this thermally responsive switch, a very thin metal plate is used so that the movable plate to which the movable contact is attached can operate in accordance with the movement of the bimetal. If the movable plate is thin, distortion due to plastic deformation may occur when the movable contact is attached, welded to the conductive base, or when the movable plate is subjected to bending stress when operated as a switch. However, there is a problem that the contact pressure between the movable contact and the fixed contact and the distance between the contacts at the time of opening do not fall within a predetermined range.
[0013]
[Means for Solving the Problems]
The present invention relates to an improvement of Japanese Patent Application No. 9-322244.
[0014]
Its feature is that it has a bottomed cylindrical metal container and a metal plate provided with a through hole, and the lead plate pin is electrically insulated from the through hole of this metal plate. A cover plate is formed by being fixed through, and the cover plate is hermetically fixed to the opening end of the container by welding to form an airtight container, which is drawn into a shallow dish and provided with a through hole in the center. The thermally responsive plate performs a reversal and return operation at a predetermined temperature to contact or open the movable contact with the fixed contact, and a fixed contact portion is provided in the airtight container of the lead terminal pin. A highly rigid movable plate support is fixed to the inner surface of the hermetic container of the metal plate, and one end serving as a fixed portion of the movable plate having flexible elasticity is fixed to the movable plate support. Made of a conductive metal plate, the end opposite the fixed part at all times A biasing force is applied so that the corresponding free end side is pressed against the movable plate support side. A movable contact is fixed to the free end side of the movable plate, and a member fixed to the free end side of the movable plate is heated. In a thermally responsive switch in which both are connected so that the movable plate is driven by the thermally responsive plate by being loosely fitted and held in the through hole of the responsive plate, the free end of the movable plate has a heat A through-hole that is slightly smaller in diameter than the through-hole provided in the response plate is provided, and the movable contact has one end as a large diameter portion and the other end as a small diameter portion, and at least a thermal response is provided between the large diameter portion and the small diameter portion. A thermally responsive plate loosely fitting portion having a diameter that passes through the through hole of the plate but cannot be inserted into the through hole of the movable plate is provided, and the small diameter portion of the movable contact is inserted through the through hole of the thermally responsive plate and the movable plate. The tip of the movable contact small diameter portion is deformed and the heat responsive plate loosely fitting portion The movable plate is sandwiched and fixed between the end faces, it lies in the loosely holding the thermally responsive plate in thermally responsive plate loosely fitting portions of the movable contact.
[0015]
Yet another feature is that a free-side end of the movable plate is provided with a through-hole that is slightly smaller in diameter than the through-hole provided in the thermally responsive plate, and the movable contact consists of a contact member and a thermally responsive plate loose-fitting member. The contact member has one end as a contact portion, and the contact member is welded to the distal end of the thermally responsive plate loosely fitting portion inserted through the through hole of the thermally responsive plate via the through hole of the movable plate. The movable contact is in a thermally responsive switch that holds and fixes the movable plate around the welded portion and loosely holds the thermally responsive plate by the thermally responsive plate loosely fitting portion.
[0016]
Another feature is that it has a movable contact and a thermally responsive plate loose fitting member, and the movable contact is directly fixed to the movable plate by welding. The thermally responsive plate loosely fitted member has one end having a large diameter and the other end is a thermally responsive plate. The thermally responsive plate loosely fitting portion is inserted into the through hole of the thermal responsive plate, and the thermally responsive plate loosely fitted portion is inserted into the through hole of the thermally responsive plate. The surface where the movable contact is welded The tip of the thermally responsive plate loosely fitting portion is welded to the back surface so that the thermally responsive plate is connected to the movable plate and loosely held.
[0017]
Furthermore, in the thermally responsive switch of the present invention, a through hole having a diameter slightly smaller than the through hole of the thermally responsive plate is provided on the free end side of the movable plate, and the movable contact has one end as a large diameter portion and the other end as a small diameter portion. In addition, a thermal reaction plate loose fitting portion having a diameter that passes through at least the through hole of the thermal reaction plate but cannot be inserted into the through hole of the movable plate is provided between the large diameter portion and the small diameter portion, The movable contact inserted through the through hole of the movable plate has a movable plate welded and fixed to the end face of the thermally responsive plate loosely fitting portion, and the thermally responsive plate is loosely fitted and held by this thermally responsive plate loosely fitted portion. And
[0018]
Another feature is that the small-diameter portion of the movable contact is inserted through a reinforcing plate having a through hole together with the thermally responsive plate and the movable plate, and the movable contact is connected to the end surface of the thermally responsive plate loosely fitting portion via the reinforcing plate. This is because the movable plate is fixed.
[0019]
Yet another feature is that a fixed plate for preventing deformation around the fixed portion is welded to the fixed portion of the movable plate so as to sandwich the movable plate with the movable plate support.
[0020]
In addition, an electrically insulating positioning member is inserted between the movable plate support to which the movable plate of the thermally responsive switch is fixed and the fixed contact portion, and the positioning member is sandwiched between the movable plate support and the fixed contact portion. The positional relationship between the movable contact and the fixed contact is defined.
[0021]
DETAILED DESCRIPTION OF THE INVENTION
Next, an embodiment of the thermally responsive switch of the present invention will be described with reference to the drawings. FIG. 1 is a longitudinal sectional view of an embodiment of a thermally responsive switch according to the present invention, FIG. 2 is a transverse sectional view thereof, and FIG. 3 is a sectional view taken along the line AA of FIG. Further, FIG. 4 shows a movable contact used in the present invention, and FIG. 5 shows an exploded perspective view of a thermally responsive switch in which a container is omitted.
[0022]
This heat responsive switch 1 is hermetically sealed by a metal container 2 having a bottomed cylindrical shape with one of the cylinders closed, a metal plate 3A and its through hole 3B, and an insulating filler 4 such as glass. The cover plate 3 is composed of the lead terminal pins 5 fixed to each other. The opening end of the container 2 is hermetically fixed to the vicinity of the peripheral edge of the metal plate 3A of the cover plate 3 by welding or the like over the entire circumference, and both constitute an airtight container. A gas mixture containing a gas having a composition selected from the viewpoint of thermal conductivity and the like is sealed inside the hermetic container, and this hermetic structure can keep the composition without changing over a long period of time. For example, in the embodiment, helium gas having good thermal conductivity in the sealing gas is 75% in the volume ratio, and 25% is nitrogen, but this helium content is 10% or more from the viewpoint of thermal conductivity. In addition, if the concentration of helium is too high, the withstand voltage between contacts in the contact open state is lowered, so 90% or less is preferable.
[0023]
A substantially prismatic fixed contact portion 6 is conductively fixed to the end portion of the lead terminal pin 5 of the lid plate 3 on the inner side of the hermetic container. In this embodiment, the lead terminal pin 5 and a separate fixed contact portion 6 are provided as an example. However, for example, the lead terminal pin 5 is extended to be able to contact and separate from a movable contact described later. It is good also as a structure which makes the vicinity of a front-end | tip a fixed contact part by processing to a crank shape so that it may become, or attaching eccentrically with respect to 3A of metal plates.
[0024]
One end of a movable plate support 7 having high rigidity is fixed on the metal plate 3 A of the lid plate 3. The movable plate support 7 is composed of a metal plate having a space portion 7B in the center so as to maintain a necessary insulation distance from the lead terminal pin 5 and the fixed contact portion 6, and the fixed side end portion 7A is bent to form L. It is shaped like a letter and is provided so as to be substantially parallel to the fixed contact portion 6 as a whole. One end of a movable plate 8 which is a flexible elastic plate is fixed to the movable plate support 7 by welding or the like at two attachment portions 8A. The movable plate 8 is made of a plate spring-like conductive metal plate, and is given a biasing force so as to always press the tip 8B against the movable plate support.
[0025]
The movable plate 8 uses a thin metal plate in order to achieve both a smooth movement in accordance with a reversing operation of a thermal response plate, which will be described later, and a downsizing of the switch. For this reason, simply welding at the mounting portion 8A causes bending stress to concentrate around the mounting portion 8A of the movable plate during operation of the thermally responsive plate, causing the movable plate 8 to be plastically deformed, and the above-described biasing force is reduced from the initial value. there's a possibility that. Therefore, in order to prevent this, a bending plate 11 having sufficient strength compared to the movable plate is arranged on the fixed portion during welding of the movable plate 8, in this embodiment the mounting portion 8A, by welding or the like, and the bending stress is concentrated on the mounting portion. It is preferable to prevent deformation due to, and suppress a decrease in biasing force.
[0026]
A through hole 8C is provided in the vicinity of the distal end portion 8B of the movable plate 8, and the movable contact 9 is fixed to the through hole by caulking or the like. As shown in FIG. 4 (A), the movable contact 9 has a relatively large-diameter head 9A at one end and a cylindrical small-diameter portion 9B at the other end. Between them, there is a thermally responsive plate loosely fitting portion 9C having a diameter smaller than the diameter of the head and larger than the diameter of the small diameter portion. The thickness from the head end surface 9D to the loose fitting portion end surface 9E of the loose fitting portion 9C is set to be larger than the thickness of the thermally responsive plate 10 described later. The movable contact 9 is fixed to the movable plate 8 by caulking work such as pressing, and the tip of the small diameter portion 9B is formed as shown in FIG. The Further, the movable contact 9 is made of a contact material such as silver or a silver alloy for contact with the fixed contact portion 6, but when the fixing work is performed by caulking as described above, the head 9A and the loose fitting portion are provided. For 9C, it is preferable to use a harder material than the small-diameter portion 9B because the fixing work becomes easier.
[0027]
The thermally responsive plate 10 is formed by drawing a heat-deformed metal plate such as a bimetal or a trimetal into a shallow dish shape, suddenly reverses the curve direction at a predetermined first temperature, and returns suddenly at a second temperature. To do. A through hole 10A for inserting the movable contact 9 is formed in the vicinity of the center of the diaphragm of the thermally responsive plate 10, and four slits 10B are provided radially from the through hole 10A in this embodiment. The through hole 10A has a diameter larger than that of the through hole 8C formed in the movable plate 8 described above. Further, since the portion sandwiched between these slits 10B becomes an arm 10C that enlarges the displacement amount of the surroundings, the moving amount of the movable contact 9 can be made larger than that without the slit, so You can increase the distance. Further, if the apparent distance between the contacts is the same, the amount of deviation of the movable contact 8 toward the fixed contact portion 6 increases, and as a result, the contact pressure between the contacts can be increased.
[0028]
Here, the assembly of the movable contact 9, the movable plate 8, and the thermally responsive plate 10 will be described. First, the small diameter portion 9 B of the movable contact 9 is inserted into the through hole 10 A of the thermally responsive plate 10. Here, the inner diameter of the through hole 10A is set to be slightly larger than the outer diameter of the loosely fitting portion 9C of the movable contact, and the thermally responsive plate 10 contacts the head end surface 9D of the movable contact 9. Next, the small diameter portion 9 B is inserted into the through hole 8 C of the movable plate 8. The through hole 8C of the movable plate is slightly smaller in diameter than the through hole 10A of the thermally responsive plate, and further smaller than the outer diameter of the loose fitting portion 9C of the movable contact. Touch.
[0029]
In this embodiment, a washer 12 is attached as a reinforcing plate after the movable contact 9 is inserted into the movable plate 8. This washer 12 is a metal plate having sufficient thickness and strength so as not to be deformed by caulking work of the movable contact. The washer 12 comes into contact with the periphery of the through hole 8C of the movable plate and is caused by a bias of force during the caulking process. Reinforce so that no distortion of 8 occurs. The washer 12 is not necessarily required unless distortion due to deformation becomes a problem. For example, a washer can be omitted by providing a slit around the crimped portion of the movable plate to release distortion due to deformation, or by increasing the thickness while keeping the flexible plate long and flexible.
[0030]
In this embodiment having a washer as a reinforcing plate, after the movable contact 9 is inserted into the thermally responsive plate 10, the movable plate 8, and the washer 12, the tip of the movable contact small diameter portion 9B is pressed into a portion shown in FIG. The contact portion 9F is formed by being deformed as shown. The contact portion 9F holds the washer 12 as its diameter increases before processing, and the peripheral portion of the through hole 8C of the movable plate 8 is fixed by caulking from the upper and lower surfaces with the washer 12 and the loose fitting end surface 9E of the movable contact. Here, the thermally responsive plate 10 is located in the loosely fitting portion 9C of the movable contact, and the loosely fitted portion 9C is thicker than the thermally responsive plate 10 as described above. Since it does not substantially deform, the thermally responsive plate 10 is loosely fitted and held so that its movement is not restricted. Therefore, the operating temperature at which the thermoresponsive plate 10 jumps and reverses at the above-described predetermined first temperature does not change due to the assembly. That is, the operating temperature of the thermal reaction plate 10 as a single unit and the operation temperature after being incorporated in the thermal response switch 1 coincide. For this reason, in the case of a conventional heat responsive switch having a structure in which some force is applied to the heat responsive plate, the operation temperature after the switch assembly is required because the operation temperature changes between the heat responsive plate alone and after the switch is assembled. Verification or calibration operations can be omitted in the thermally responsive switch of the present invention.
[0031]
In the present invention, since all the parts constituting the circuit of the switch are arranged on the cover plate, it is possible to directly confirm the positional relationship of each part and the operation of the switch mechanism before the container 2 is fixed to the cover plate 3. it can. Here, when adjustment of the contact pressure between the movable contact 9 and the fixed contact portion 6 and the distance between the contacts at the time of opening is necessary, the movable plate support 7 or the fixed contact portion 6 is bent to The positional relationship between the surface on which the movable contact head end surface 9D abuts and the contact surface of the fixed contact portion 6 is adjusted. In the heat responsive switch 1 of the embodiment, this adjustment operation is performed by displacing the tip 7C of the movable plate support 7 in the vertical direction in FIG. In this embodiment, as shown in FIGS. 2 and 5, the movable plate support 7 is provided with a width detail 7D in the vicinity of the fixed side end portion 7A with the lid plate so as to be easily deformed during adjustment. Since the adjustment is made without deforming the distal end side from the mounting portion 8A, the adjustment work can be reliably performed without changing the biasing force previously applied to the movable plate 8.
[0032]
Next, the operation of the thermally responsive switch 1 will be described with reference to cross-sectional views showing the operation states of FIGS. Normally, the bending direction of the thermally responsive plate 10 is convex toward the movable plate 8 as shown in FIG. 1, and the movable contact 9 is fixed to the fixed contact portion 6 by a biasing force applied to the movable plate 8. It is contacted by contact pressure. Therefore, the electric path by the conductive terminal pin 5 -the fixed contact portion 6 -the movable contact 9 -the movable plate 8 -the movable plate support 7 -the cover plate 3 is closed. Here, when the case where this thermal responsive switch is attached to the electric motor is considered as an example, even when an electric current flows through the electric circuit, the electric operating current of the electric motor does not substantially flow through the thermal responsive plate 10, so The influence on the operating temperature due to the self-heating of the plate 10 is negligible. In addition, since a gas mixture with good thermal conductivity containing helium is sealed in a sealed container, heat generated in the electric circuit is released to the outside through the gas mixture and the container during normal times, that is, when the ambient temperature is low. Therefore, the thermally responsive plate 10 is not reversed by Joule heat due to the resistance of the electric circuit.
[0033]
Here, for example, when the electric motor is overheated for some reason, the ambient temperature of the heat responsive switch 1 rises, and this heat is transmitted to the inside of the sealed container through the container and the mixed gas. As a result, when the thermally responsive plate 10 reaches a predetermined first temperature, the thermally responsive plate 10 jumps over and reverses its direction of curvature as shown in FIG. Therefore, both end portions of the thermally responsive plate 10 are brought into contact with the movable plate support 7 directly or via the movable plate 8, and the movable contact 9 located at the center is moved against the biasing force of the movable plate 8 to contact the contact portion 9F. Is disconnected from the fixed contact portion 6 to interrupt the electric circuit.
[0034]
In the above-described embodiment, the movable contact is fixed to the elastic plate by caulking, but may be fixed by welding instead of caulking. This example will be described with reference to FIG. The same parts as those of the above-described thermally responsive switch 1 are denoted by the same reference numerals, and detailed description thereof is omitted. In this thermally responsive switch 21, the movable contact 29 is inserted into the thermally responsive plate 10 and the movable plate 8 and then the movable contact 29 and the movable plate 8 are fixed by welding. This movable contact 29 has a relatively large-diameter head 29 at one end, a cylindrical small-diameter portion 29B at the other end, and a thermally responsive plate between the head and the small-diameter portion. A loose fitting portion 29C is provided. The tip of the small-diameter portion 29B does not require pressing as in the above-described movable contact, and has already been shaped as a contact portion before assembly.
[0035]
The thermally responsive plate 10 having a through hole larger than the movable plate 8 is inserted through the loose fitting portion 29C, and the movable plate 8 contacts the loose fitting portion end surface 29E. Here, the loose fitting portion end face 29E is welded to the movable plate 10 to fix both of them, and by making the thickness of the loose fitting portion 29C thicker than that of the thermally responsive plate 10, the movement of the thermal responsive plate 10 is not restricted. So as to be loosely fitted. For example, when distortion caused by deformation that occurs during welding becomes a problem for the operation of the movable plate, the deformation may be suppressed by welding while applying a reinforcing plate such as a washer to the welded portion. You may provide the slit for releasing deformation distortion around a welding part.
[0036]
In addition to the contact structure described above, for example, a structure shown in FIGS. 8A and 8B may be used. In FIG. 8A, the movable contact 31 is divided into a contact member 31A and a thermally responsive plate loose fitting member 31B, and these members are connected to the through holes 8C and 10A of the movable plate 8 and the thermally responsive plate 10, respectively. The movable plate 8 and the thermally responsive plate 10 are sandwiched and fixed by both members 31A and 31B of the movable contact at the time of welding. Further, in the embodiment of FIG. 8B, a movable plate 48 having no through-hole is used, and a movable contact 41 is welded to the lower surface of the movable plate 48 in the figure, and on the rear surface of the movable plate, that is, the upper surface in the figure. Is welded to a position substantially corresponding to the movable contact 41 with a thermally responsive plate loosely fitting member 42 having a large diameter portion and a thermally responsive plate loosely fitted portion. In the embodiment of FIG. 8B, for example, the energization path can be shortened by offsetting the welding position between the thermally responsive plate loosely fitting member and the movable contact, and heat generation on the energization path can be reduced. 8A and 8B, the heat responsive plate 10 is loosely held by the heat responsive plate loose fitting portions in the through holes 10A and is connected to the free end of the movable plate 8 as described above. This is the same as each of the examples.
[0037]
In this embodiment, the contact pressure between the contacts is adjusted by deforming the movable plate support as described above. In other words, this is to define the positional relationship between the movable plate support and the fixed contact. However, when the movable plate support is deformed, so-called spring back is also generated. Therefore, this adjustment work needs to be performed in consideration of this point, and the workability is poor. Further, in order to eliminate the adjustment work, it is necessary to manage the dimensional tolerance of each part and the dimensional tolerance at the time of assembly very strictly, which is difficult.
[0038]
FIG. 9 shows an improvement made to facilitate this adjustment work. Also in this embodiment, the same parts as those in the above-described embodiments are denoted by the same reference numerals, and detailed description thereof is omitted. The thermally responsive switch 51 of this embodiment has a fixed contact 56 extending along the movable plate support 7 and is made of an insulator for defining the distance between the two near the tip. A positioning member 52 is disposed. Next, adjustment work by this configuration will be described. In the embodiment, the fixed contact portion 56 and the movable plate support 7 are assembled on the lid plate with their tip portions approaching each other in advance so as to increase the contact pressure between the contacts. Instead of deforming either member, a positioning member 52 having a predetermined thickness is sandwiched between the two members.
[0039]
In the embodiment, as shown in the drawing, the positioning member 52 has a wedge shape with respect to the insertion direction, and both ends are touched to the movable plate support 7 from the front to the back of the drawing. As described above, the positioning member 52 inserted between the fixed contact portion 56 and the movable plate support 7 has the upper end in the drawing at the top end of the movable plate support 7. 7C The lower surface of the center portion is in contact with the vicinity of the front end portion of the fixed contact portion 56. The positioning member is sandwiched between the fixed contact portion and the movable plate support member, but is more reliably held by providing a detent on either member. By using the positioning member in this way, the gap between the two members that is narrower than the appropriate value is expanded to a predetermined positional relationship. Thus, according to the present embodiment, the adjustment work is completed simply by inserting and positioning the positioning member 52 between the fixed contact and the movable plate support, and the work can be greatly simplified.
[0040]
In the embodiments described so far, a container having a closed cylindrical shape is used as the container. However, this shape is not limited to the cylindrical shape, for example, a container 62 of the thermally responsive switch 61 shown in FIG. The cross-sectional shape may be a cylindrical container other than a circle such as an ellipse. Hereinafter, although this thermal responsive switch 61 is demonstrated, the same code | symbol is attached | subjected to the same part as the above-mentioned thermal responsive switch 1, and detailed description is abbreviate | omitted. In this thermal responsive switch 61, the cross-sectional shape of the container 62 is elliptical, so that the metal plate 63A of the lid plate 63 that is in contact with and fixed to the opening is also elliptical. The movable plate support 67 has a fixed side end 67 A that is fixed to the metal plate 63 so that the height is suppressed along the inner peripheral surface of the container 62. Except for these points, the operation is the same as that of the above-described thermally responsive switch 1 including its operation.
[0041]
Thus, by making the cross-sectional shape of the container elliptical, the distance between the container 62 and the thermally responsive plate 10 becomes closer than that of the circular cross-section described above, so that the thermal response of the thermally responsive plate 10 to ambient temperature changes. Sexuality is improved. In addition, it is easy to attach to the heating element, and the orientation of the thermal reaction plate can be known from the shape of the container even after the sealed container is configured, so it can be attached so that the thermal reaction plate faces the heating element. It becomes easy and thermal response can be further improved.
[0042]
In the above description of each embodiment, the through holes of the movable plate and the thermally responsive plate, and the movable contact portion inserted through these through holes are assumed to be circular. Needless to say, the equivalent effect can be obtained by replacing an ellipse or polygon with a diameter or a thickness.
[0043]
【The invention's effect】
According to the thermally responsive switch of the present invention, even when it is used for an inverter-controlled motor whose current changes according to the load, the change in the operating current has little influence on the operating conditions and the external temperature change Therefore, it is possible to provide a straight-cut switch that can cope with the above with a simple structure.
[0044]
In addition, by placing a contact plate or washer to disperse the stress on the part where welding or caulking force is applied to the movable plate during assembly, the movable plate is less likely to be distorted, making a thinner and more flexible metal plate. Can be used. In addition, when an electric circuit is formed by a fixed contact and a movable contact, regardless of the contact pressure between the two contacts, no external force is applied to the heat responsive plate. It is possible to match the operating temperature given at the time of the operation, and the operation temperature confirmation work after the switch is completed can be omitted.
[0045]
In addition, since the airtight container has a structure in which the lid plate is tightly sealed to the opening of the metal bottomed cylindrical container by a method such as welding, high airtightness and pressure resistance can be easily obtained. . As a result, by enclosing a gas having a desired composition in the space in the hermetic container, the thermal conductivity between the thermally responsive plate and the container, and the withstand voltage in a state where the movable contact and the fixed contact are open. Can be selected.
[0046]
In addition, by arranging all the components that make up the circuit of the switch on the cover plate, the positional relationship of each part and the operation of the switch mechanism before the airtight container is formed in the manufacturing process, that is, before the cover plate and the container are fixed. Can be confirmed directly, making assembly work easier. Further, in this manufacturing process, a positioning member of a predetermined size is sandwiched between the fixed contact and the movable plate support, and the positional relationship between the fixed contact and the movable contact is set to a predetermined value, so that complicated adjustment work is performed. Can be omitted.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view of an embodiment of a thermally responsive switch of the present invention.
2 is a cross-sectional view of the thermally responsive switch of FIG.
3 is a cross-sectional view taken along the line AA of the thermally responsive switch of FIG. 1;
FIG. 4 shows another embodiment of the movable contact used in the thermally responsive switch of the present invention.
5 is an exploded perspective view of the thermally responsive switch of FIG. 1 with the container 2 removed.
6 is a longitudinal sectional view showing the operating state of the thermally responsive switch of FIG. 1. FIG.
FIG. 7 shows another embodiment of the thermally responsive switch of the present invention.
8 shows another embodiment of the movable contact used in the thermally responsive switch of FIG.
FIG. 9 shows another embodiment of the present invention.
FIG. 10 shows another embodiment of the thermally responsive switch of the present invention.
[Explanation of symbols]
1, 21, 51, 61: Thermally responsive switch
2,62: Container
3, 63: Cover plate
5: Lead terminal pin
6: Fixed contact
7, 67: Movable plate support
8: Movable plate
8C: Through hole
9, 29, 31, 41: movable contact
9A: head
9B: Small diameter part
9C: Free fitting part
9D: head end face
9E: Free fitting part end surface
9F: contact part
10: Thermally responsive plate
10A: Through hole
10B: Slit
10C: Arm
11: Address plate
12: Washer (reinforcement plate)
42: Thermally responsive plate loose-fitting member
52: Positioning member

Claims

有底筒形の金属製容器と、
貫通孔を設けられた金属板を有し、
この金属板の貫通孔に導電性のリード端子ピンが電気的に絶縁された状態で気密に貫通固定されて蓋板を構成し、
この蓋板を前記容器の開口端部に溶接によって気密に固定することにより気密容器を構成し、
浅い皿状に絞り成形され且つほぼ中心に貫通孔を設けた熱応動板が所定の温度で反転及び復帰動作を行うことにより可動接点を固定接点に接触または開離し、
前記リード端子ピンの前記気密容器内には固定接点部が設けられ、
前記蓋板の金属板の前記気密容器内面には剛性の高い可動板支持体が固着され、
可動板支持体にはしなやかな弾性を有した可動板の一端を固定部として固着され、
この可動板は板バネ状の導電性金属板からなり固定部とは逆の端部である自由端側を常に可動板支持体側に押しつけるように偏倚力が与えられており、
この可動板の自由端側には可動接点が固定され、
さらに可動接点が熱応動板の貫通孔に挿通され熱応動板を遊嵌保持することによって可動板が熱応動板によって駆動されるように両者が連結された熱応動スイッチにおいて、
前記可動板の自由端側には熱応動板に設けられた貫通孔よりも一回り直径の小さい貫通孔を設け、
可動接点は一端を大径部、他端を小径部とし、この大径部と小径部の間には少なくとも熱応動板の貫通孔には通るが可動板の貫通孔には挿通できない径を有する熱応動板遊嵌部を設け、
可動接点の小径部は前記熱応動板及び可動板の貫通孔に挿通されており、
可動接点小径部の先端は変形され前記熱応動板遊嵌部の端面とで可動板を挟持固定しており、
熱応動板は可動接点の熱応動板遊嵌部に遊嵌保持されていることを特徴とする熱応動スイッチ。A bottomed cylindrical metal container,
Having a metal plate provided with through holes,
In the state where the conductive lead terminal pin is electrically insulated in the through hole of the metal plate, the cover plate is configured to be hermetically penetrated and fixed.
An airtight container is configured by fixing the lid plate in an airtight manner to the opening end of the container by welding,
A thermally responsive plate that is drawn into a shallow dish shape and has a through hole at the center performs inversion and return operations at a predetermined temperature, thereby bringing the movable contact into contact with or separating from the fixed contact,
A fixed contact portion is provided in the airtight container of the lead terminal pin,
A highly rigid movable plate support is fixed to the inner surface of the hermetic container of the metal plate of the lid plate,
One end of the movable plate having supple elasticity is fixed to the movable plate support as a fixed portion,
This movable plate is made of a conductive metal plate in the form of a leaf spring, and a biasing force is applied so that the free end side, which is the end opposite to the fixed portion, is always pressed against the movable plate support.
A movable contact is fixed to the free end of the movable plate,
Further, in the thermally responsive switch in which the movable contact is inserted into the through hole of the thermally responsive plate and the thermally responsive plate is loosely fitted and held so that the movable plate is driven by the thermally responsive plate,
On the free end side of the movable plate, a through hole having a diameter smaller than the through hole provided in the thermally responsive plate is provided,
The movable contact has a large diameter portion at one end and a small diameter portion at the other end. Between the large diameter portion and the small diameter portion, the movable contact has a diameter that passes through at least the through hole of the thermally responsive plate but cannot be inserted into the through hole of the movable plate. A heat-responsive plate loose fitting part is provided,
The small-diameter portion of the movable contact is inserted through the thermally responsive plate and the through hole of the movable plate,
The tip of the movable contact small-diameter portion is deformed and the movable plate is sandwiched and fixed with the end face of the thermally responsive plate loose fitting portion,
A thermally responsive switch, wherein the thermally responsive plate is loosely held in a thermally responsive plate loosely fitting portion of a movable contact.

有底筒形の金属製容器と、
貫通孔を設けられた金属板を有し、
この金属板の貫通孔に導電性のリード端子ピンが電気的に絶縁された状態で気密に貫通固定されて蓋板を構成し、
この蓋板を前記容器の開口端部に溶接によって気密に固定することにより気密容器を構成し、
浅い皿状に絞り成形され且つほぼ中心に貫通孔を設けた熱応動板が所定の温度で反転及び復帰動作を行うことにより可動接点を固定接点に接触または開離し、
前記リード端子ピンの前記気密容器内には固定接点部が設けられ、
前記蓋板の金属板の前記気密容器内面には剛性の高い可動板支持体が固着され、
可動板支持体にはしなやかな弾性を有した可動板の一端を固定部として固着され、
この可動板は板バネ状の導電性金属板からなり固定部とは逆の端部である自由端側を常に可動板支持体側に押しつけるように偏倚力が与えられており、
この可動板の自由端側には可動接点が固定され、
さらに可動接点が熱応動板の貫通孔に挿通され熱応動板を遊嵌保持することによって可動板が熱応動板によって駆動されるように両者が連結された熱応動スイッチにおいて、
前記可動板の自由端側には熱応動板に設けられた貫通孔よりも一回り直径の小さい貫通孔を設け、
可動接点は接点部材と熱応動板遊嵌部材とからなり、
この接点部材はその一端を接触部としており、
熱応動板の貫通孔に挿通された熱応動板遊嵌部材の熱応動板遊嵌部先端に可動板の貫通孔を介して接点部材が溶接され、
可動接点はその溶接部周辺で可動板を挟持固定していると共に熱応動板を熱応動板遊嵌部で遊嵌保持していることを特徴とする熱応動スイッチ。A bottomed cylindrical metal container,
Having a metal plate provided with through holes,
In the state where the conductive lead terminal pin is electrically insulated in the through hole of the metal plate, the cover plate is configured to be hermetically penetrated and fixed.
An airtight container is configured by fixing the lid plate in an airtight manner to the opening end of the container by welding,
A thermally responsive plate that is drawn into a shallow dish shape and has a through hole at the center performs inversion and return operations at a predetermined temperature, thereby bringing the movable contact into contact with or separating from the fixed contact,
A fixed contact portion is provided in the airtight container of the lead terminal pin,
A highly rigid movable plate support is fixed to the inner surface of the hermetic container of the metal plate of the lid plate,
One end of the movable plate having supple elasticity is fixed to the movable plate support as a fixed portion,
This movable plate is made of a conductive metal plate in the form of a leaf spring, and a biasing force is applied so that the free end side, which is the end opposite to the fixed portion, is always pressed against the movable plate support.
A movable contact is fixed to the free end of the movable plate,
Further, in the thermally responsive switch in which the movable contact is inserted into the through hole of the thermally responsive plate and the thermally responsive plate is loosely fitted and held so that the movable plate is driven by the thermally responsive plate,
On the free end side of the movable plate, a through hole having a diameter smaller than the through hole provided in the thermally responsive plate is provided,
The movable contact consists of a contact member and a thermally responsive plate loose fitting member,
This contact member has one end as a contact portion,
The contact member is welded through the through hole of the movable plate to the distal end of the thermally responsive plate loosely fitting portion of the thermally responsive plate loosely fitting member inserted through the through hole of the thermally responsive plate,
A thermally responsive switch characterized in that the movable contact has a movable plate sandwiched and fixed around its welded portion, and the thermally responsive plate is loosely fitted and held by a thermally responsive plate loosely fitting portion.

有底筒形の金属製容器と、
貫通孔を設けられた金属板を有し、
この金属板の貫通孔に導電性のリード端子ピンが電気的に絶縁された状態で気密に貫通固定されて蓋板を構成し、
この蓋板を前記容器の開口端部に溶接によって気密に固定することにより気密容器を構成し、
浅い皿状に絞り成形され且つほぼ中心に貫通孔を設けた熱応動板が所定の温度で反転及び復帰動作を行うことにより可動接点を固定接点に接触または開離し、
前記リード端子ピンの前記気密容器内には固定接点部が設けられ、
前記蓋板の金属板の前記気密容器内面には剛性の高い可動板支持体が固着され、
可動板支持体にはしなやかな弾性を有した可動板の一端を固定部として固着され、
この可動板は板バネ状の導電性金属板からなり固定部とは逆の端部にあたる自由端側を常に可動板支持体側に押しつけるように偏倚力が与えられており、
この可動板の自由端側には可動接点が固定され、
さらに可動板の自由端側に可動接点とは別に固定された熱応動板遊嵌部材が熱応動板の貫通孔に挿通され熱応動板を遊嵌保持することによって可動板が熱応動板によって駆動されるように両者が連結された熱応動スイッチにおいて、
可動接点は前記可動板に直接溶接固定され、
熱応動板遊嵌部材は一端を大径部、他端を熱応動板の貫通孔に挿通する熱応動板遊嵌部とされ、
熱応動板の貫通孔にはこの熱応動板遊嵌部が挿通されており、
前記可動板の可動接点が溶接された面の裏面に熱応動板遊嵌部の先端が溶接されていることで熱応動板を可動板に連結し且つ遊嵌保持していることを特徴とする熱応動スイッチ。A bottomed cylindrical metal container,
Having a metal plate provided with through holes,
In the state where the conductive lead terminal pin is electrically insulated in the through hole of the metal plate, the cover plate is configured to be hermetically penetrated and fixed.
An airtight container is configured by fixing the lid plate in an airtight manner to the opening end of the container by welding ,
The movable contact contacts or separable with the fixed contact by shallow is dish-shaped to draw forming and thermally responsive plate provided with through holes substantially centered performs inversion and return operation at a predetermined temperature,
A fixed contact portion is provided in the airtight container of the lead terminal pin,
A highly rigid movable plate support is fixed to the inner surface of the hermetic container of the metal plate of the lid plate,
One end of the movable plate having supple elasticity is fixed to the movable plate support as a fixed portion,
This movable plate is made of a plate spring-like conductive metal plate, and a biasing force is applied so that the free end side corresponding to the end opposite to the fixed portion is always pressed against the movable plate support side.
A movable contact is fixed to the free end of the movable plate,
In addition, a thermally responsive plate loosely fitted member fixed separately from the movable contact on the free end side of the movable plate is inserted into the through hole of the thermally responsive plate, and the thermally responsive plate is loosely fitted and held so that the movable plate is driven by the thermally responsive plate. In a thermally responsive switch in which both are connected,
The movable contact is fixed directly to the movable plate by welding,
The thermally responsive plate loosely fitting member has a large diameter portion at one end and a thermally responsive plate loosely fitted portion inserted into the through hole of the thermally responsive plate,
The thermal reaction plate loose-fitting part is inserted through the through hole of the thermal reaction plate,
The tip of the thermally responsive plate loosely fitting portion is welded to the back surface of the surface on which the movable contact of the movable plate is welded, so that the thermally responsive plate is connected to the movable plate and held loosely. Thermally responsive switch.

有底筒形の金属製容器と、
貫通孔を設けられた金属板を有し、
この金属板の貫通孔に導電性のリード端子ピンが電気的に絶縁された状態で気密に貫通固定されて蓋板を構成し、
この蓋板を前記容器の開口端部に溶接によって気密に固定することにより気密容器を構成し、
浅い皿状に絞り成形され且つほぼ中心に貫通孔を設けた熱応動板が所定の温度で反転及び復帰動作を行うことにより可動接点を固定接点に接触または開離し、
前記リード端子ピンの前記気密容器内には固定接点部が設けられ、
前記蓋板の金属板の前記気密容器内面には剛性の高い可動板支持体が固着され、
可動板支持体にはしなやかな弾性を有した可動板の一端を固定部として固着され、
この可動板は板バネ状の導電性金属板からなり固定部とは逆の端部である自由端側を常に可動板支持体側に押しつけるように偏倚力が与えられており、
この可動板の自由端側には可動接点が固定され、
さらに可動接点が熱応動板の貫通孔に挿通され熱応動板を遊嵌保持することによって可動板が熱応動板によって駆動されるように両者が連結された熱応動スイッチにおいて、
可動板の自由端側には熱応動板の貫通孔よりも一回り直径の小さい貫通孔を設け、
可動接点は一端を大径部、他端を小径部とし、この大径部と小径部の間には少なくとも熱応動板の貫通孔には通るが可動板の貫通孔には挿通できない径を有する熱応動板遊嵌部を設けられ、
前記熱応動板及び可動板の貫通孔に挿通された可動接点はその熱応動板遊嵌部の端面に可動板を溶接固定されており、
熱応動板をこの熱応動板遊嵌部で遊嵌保持していることを特徴とする熱応動スイッチ。A bottomed cylindrical metal container,
Having a metal plate provided with through holes,
In the state where the conductive lead terminal pin is electrically insulated in the through hole of the metal plate, the cover plate is configured to be hermetically penetrated and fixed.
An airtight container is configured by fixing the lid plate in an airtight manner to the opening end of the container by welding ,
The movable contact contacts or separable with the fixed contact by shallow is dish-shaped to draw forming and thermally responsive plate provided with through holes substantially centered performs inversion and return operation at a predetermined temperature,
A fixed contact portion is provided in the airtight container of the lead terminal pin,
A highly rigid movable plate support is fixed to the inner surface of the hermetic container of the metal plate of the lid plate,
One end of the movable plate having supple elasticity is fixed to the movable plate support as a fixed portion,
This movable plate is made of a conductive metal plate in the form of a leaf spring, and a biasing force is applied so that the free end side, which is the end opposite to the fixed portion, is always pressed against the movable plate support.
A movable contact is fixed to the free end of the movable plate,
Further, in the thermally responsive switch in which the movable contact is inserted into the through hole of the thermally responsive plate and the thermally responsive plate is loosely fitted and held so that the movable plate is driven by the thermally responsive plate,
On the free end side of the movable plate, a through hole having a diameter slightly smaller than the through hole of the thermally responsive plate is provided,
The movable contact has a large diameter portion at one end and a small diameter portion at the other end. Between the large diameter portion and the small diameter portion, the movable contact has a diameter that passes through at least the through hole of the thermally responsive plate but cannot be inserted into the through hole of the movable plate. Provided with a heat responsive plate loose fit,
The movable contact inserted through the through hole of the thermally responsive plate and the movable plate is fixed by welding the movable plate to the end face of the thermally responsive plate loosely fitting portion,
A heat responsive switch, wherein the heat responsive plate is loosely held by the heat responsive plate loosely fitting portion.

可動接点の小径部は前記熱応動板及び可動板とともに貫通孔を有した補強板に挿通されており、
可動接点が前記補強板を介して熱応動板遊嵌部の端面に可動板を固定していることを特徴とする請求項１または請求項４に記載の熱応動スイッチ。The small-diameter portion of the movable contact is inserted through a reinforcing plate having a through hole together with the thermally responsive plate and the movable plate,
The thermally responsive switch according to claim 1 or 4, wherein the movable contact fixes the movable plate to an end face of the thermally responsive plate loosely fitting portion via the reinforcing plate.

可動板の固定部には固定部周囲の変形を防ぐためのあて板が可動板を可動板支持体とで挟むようにして溶着されていることを特徴とする請求項１乃至請求項５のいずれか１項に記載の熱応動スイッチ。 6. The fixing part of the movable plate is welded so as to sandwich a movable plate between the movable plate and the movable plate support so as to prevent deformation around the fixed part. Thermally responsive switch according to item.

可動板が固着された可動板支持体と固定接点部との間に電気絶縁性の位置決め部材を挿入し、可動板支持体と固定接点部によって位置決め部材を挟持する事により、可動接点と固定接点との位置関係を規定することを特徴とする請求項１乃至請求項６のいずれか１項に記載の熱応動スイッチ。 An electrically insulating positioning member is inserted between the movable plate support to which the movable plate is fixed and the fixed contact portion, and the movable contact and the fixed contact are sandwiched between the movable plate support and the fixed contact portion. The thermal responsive switch according to any one of claims 1 to 6, characterized in that a positional relationship between the thermal responsive switch and the switch is defined.