JP3945065B2

JP3945065B2 - Manufacturing method of electromagnet for electromagnetic relay

Info

Publication number: JP3945065B2
Application number: JP05173499A
Authority: JP
Inventors: 敏光藤原; 健西山
Original assignee: Omron Corp
Current assignee: Omron Corp
Priority date: 1999-02-26
Filing date: 1999-02-26
Publication date: 2007-07-18
Anticipated expiration: 2019-02-26
Also published as: JP2000252116A

Description

【０００１】
【発明の属する技術分野】
本発明は、電磁リレー用電磁石及びその製造方法に係り、特に、鉄芯とヨークとの継合工程において、磁気ひずみを抑えることにより、小電流で確実な動作特性が得られるとともに、鉄芯とヨークとの公差管理も容易に行なえ、リレー接点の初期状態における精度を向上させた電磁リレー用電磁石及びその製造方法に関する。
【０００２】
【従来の技術】
通常、電磁リレーに使用される電磁石は、図１６，図１７に示すように、コイル１を外周に巻装した鉄芯２の軸方向両端部分にスプール３を取り付け、断面Ｌ字状のヨーク４のフランジ部５に取り付けて構成されている。
【０００３】
そして、図１７に示すように、電磁石に通電された際、鉄芯２が可動鉄片６を矢印ａ方向に吸着し、また、電磁石への通電が停止した際、図示しないバネ手段により矢印ｂ方向に可動鉄片６が動作することにより、接点のＯＮ・ＯＦＦが行なわれる。
【０００４】
ところで、上記鉄芯２とヨーク４との結合構造は、図１８に示すように、ヨーク４のフランジ部５に開設した挿入穴７に鉄芯２を嵌め込んで継合しているが、鉄芯２とヨーク４との継合方法は、かしめ加工方法と溶接加工方法が従来からよく知られている。
【０００５】
まず、かしめ加工方法は、図１９に示すように、鉄芯２の径に対してヨーク４に設ける挿入穴７の径を若干大径に設定しておき、鉄芯２を挿入穴７内に挿入した後、鉄芯２の軸方向両端末をプレス機により押圧加工することにより、挿入穴７に挿通した箇所をかしめ、ヨーク４に対する鉄芯２の継合固定を行なっている。
【０００６】
また、図示はしないが、溶接加工方法は、ヨーク４の挿入穴７内に鉄芯２を圧入した後、フランジ部５下面の挿入穴７廻りに沿ってレーザー溶接や抵抗溶接等によりヨーク４に対する鉄芯２の継合固定を行なっている。
【０００７】
【発明が解決しようとする課題】
しかしながら、かしめ加工方法による鉄芯とヨークとの継合方法においては、鉄芯２及びヨーク４が軟磁性材料を使用しているため、かしめ加工により鉄芯２に塑性ひずみが発生するという問題点があった。
【０００８】
塑性ひずみが発生した場合、磁気特性が大きく劣化するとともに、保磁力が大きくなる傾向にある。例えば、電磁リレー用電磁石に適用した場合には、磁気特性の劣化により動作特性の低下を招き、確実なＯＮ・ＯＦＦ切り替えが期待できないという欠点があった。また、保磁力が増大した場合には、ＯＮ・ＯＦＦ切り替えに大きな電流を要することになり、コンパクト化の支障になるという欠点があった。
【０００９】
更に、かしめ加工方法においては、プレス機でかしめ加工を行なうが、その際、鉄芯２のスプリングバックにより鉄芯２の高さ位置を精度良く管理できず、鉄芯２の高さ位置にばらつきが生じやすく、このばらつきを少なくして、接点の初期状態を良好に保つための管理が非常に面倒になるという問題点があった。
【００１０】
一方、溶接加工方法においても、鉄芯２とヨーク４との継合強度に難があるとともに、挿入穴７と鉄芯２との間の空隙部が原因となる磁気特性の劣化があるため、同様に安定した動作特性が得られないという欠点が指摘されている。
【００１１】
この発明は、このような事情に鑑みてなされたもので、鉄芯内部に塑性ひずみを生じることなく、安定した動作特性が得られるとともに、ヨークに対する鉄芯の取付位置の公差管理も簡単かつ精度良く行なえることにより、接点の初期状態を簡単に確保できる電磁リレー用電磁石及びその製造方法を提供することを目的としている。
【００１２】
【課題を解決するための手段】
この出願の発明は、外周にコイルを巻装した鉄芯を断面Ｌ字状のヨークのフランジ部に設けた挿入穴に継合する電磁リレー用電磁石の製造方法であります。この電磁リレー用電磁石の製造方法は、ヨークのフランジ部に鉄芯の径よりやや大径の挿入穴が開設され、該挿入穴とフランジ部の端縁との間にスリットが連通形成され、フランジ部の挿入穴に鉄芯を挿入した状態でスリット幅を縮小させるようにフランジ部を塑性変形させることにより、鉄芯を挿入穴内で締め付け、鉄芯とヨークとを継合させ、かつフランジ部には、スリットを境とした左右側に突片が設けられ、突片同士を接合方向に塑性変形させることにより、スリット幅を縮小させて、鉄芯とヨークとの継合を行い、更に一方側の突片の先端を鉤状に延設し、突片同士をスリット幅の縮小方向に塑性変形させた後、上記鉤状部と他方側の突片とを係止させることにより、鉄芯とヨークとの継合状態をロックしたことを特徴とするものであります。
【００１３】
従って、本発明によれば、ヨークのフランジ部に設けた挿入穴内に鉄芯を挿入した後、スリット幅の縮小方向にフランジ部を塑性変形させることにより、鉄芯をヨークに継合固定できるため、磁路に関係ないフランジ部のスリット形成部分にのみ塑性ひずみが生じるだけであり、鉄芯には塑性ひずみが全く発生せず、電磁石に磁気特性の劣化が生じることがなく、また鉄芯高さにばらつきが生じない。また、スリット幅を広く設定しておけば、鉄芯の継合力を強化できる等、スリット幅により鉄芯とヨークとの継合力を制御できる。
また、スリットを挟んで左右に突片が形成されているため、スリット幅を縮小させるには、突片同士を接合方向に塑性変形されば良く、かしめ加工が容易であり、磁性ひずみを磁路に関係のない突片部分だけに規制できる。更に、スリット幅を縮小する方向に突片同士を塑性変形させてフランジ部の挿入穴内に鉄芯を挿入した後、一方側の突片に設けた鉤状部を他方側の突片に係止すれば、スリットの開きが防止でき、ヨークと鉄芯との継合力を長期に亘り強固に維持できる。
【００１４】
また、本発明の電磁リレー用電磁石の製造方法は、スリットに２分割される突片同士を内方に向けて塑性変形させた後、スリットの開きを規制するリング状拘束部材を突片同士に嵌め込み固着することを特徴とするものであります。
【００１５】
従って、本発明によれば、スリットに２分割される突片同士を内方に向けて塑性変形させた後、塑性ひずみが全く生じないため、磁性部品の磁気劣化がなく、電磁石の磁気特性劣化が生じない。また、リング状拘束部材を取外すことで塑性ひずみを与えることなく鉄芯の分離が行なえるために鉄芯とヨークの再利用が可能となる。
【００１６】
更に、本発明の電磁リレー用電磁石の製造方法は、リング状拘束部材を嵌め込む突片は、先端に向けてテーパー状に設定されていることを特徴とするものであります。
【００１７】
従って、本発明によれば、リング状拘束部材を突片に深く差し込めば、それだけ突片同士をきつく接合することができ、ヨークと鉄芯との継合力を強固に維持できる。
【００１８】
【発明の実施の形態】
以下、本発明に係る本発明に係る電磁リレー用電磁石及びその製造方法の実施形態について、添付図面を参照しながら詳細に説明する。
【００１９】
図１は本発明に係る電磁石に使用する鉄芯とヨークとを示す斜視図、図２，図３は本発明に係る電磁石の製造方法の第１の実施形態を示す説明図、図４，図５は本発明に係る電磁石の製造方法の第２の実施形態を示す説明図、図６，図７は本発明に係る電磁石の製造方法の第３の実施形態を示す説明図、図８，図９は本発明に係る電磁石の製造方法の第４の実施形態を示す説明図、図１０，図１１は本発明に係る電磁石の製造方法の第５の実施形態を示す説明図、図１２，図１３は本発明に係る電磁石の製造方法の第６の実施形態を示す説明図、図１４は第４の実施形態の作用を示す説明図、図１５は磁性ひずみによる磁気特性低下を示すグラフである。
【００２０】
尚、電磁石の一般構成については、従来例の図１６，図１７に示すものを援用するので、ここでは詳細な説明は省略する。
【００２１】
図１において、鉄芯１０とヨーク２０との構成について説明する。尚、鉄芯１０の外周にはコイルが巻装され、かつ鉄芯１０の軸方向両端部分にはスプールが取り付けられるが、本発明においては鉄芯１０とヨーク２０との構成並びに継合方法に特徴があるため、ここでは省略する。符号１０は軟磁性材料からなる鉄芯を示し、鉄芯１０の挿入端の反対側には、円盤状のフランジ１１が形成されている。
【００２２】
一方、ヨーク２０も軟磁性材料からなり、フランジ部２１を有する断面Ｌ字状の板材から構成されており、フランジ部２１の中央に鉄芯１０の挿入穴２２が開設されているとともに、フランジ部２１の先端縁に外方に向けて突出する突片２３が突設され、この突片２３を左右に２分割するようにスリット２４が挿入穴２２と連通形成されている。従って、スリット２４を挟んで左右に一対の突片２３がフランジ部２１に一体形成され、スリット２４により挿入穴２２の径が可変できるようにしたことが特徴である。
【００２３】
次いで、鉄芯１０とヨーク２０との継合方法について図２以下の各実施形態について説明する。まず、本発明の第１の実施形態は、まず、鉄芯１０の径に対してヨーク２０のフランジ部２１に開設されている挿入穴２２径はそれよりも小径に設定されている。
【００２４】
従って、ヨーク２０の挿入穴２２に鉄芯１０を挿入させるためには、図２に示すように突片２３を図中矢印方向に左右側に押し広げ、スリット２４を拡開させて挿入穴２２の径を拡大させ、鉄芯１０を挿入した後、突片２３に加わっている外力を解除すれば、図３に示すように、突片２３がそれぞれ元位置に戻ることにより、鉄芯１０は挿入穴２２の径が縮小し、鉄芯１０に締付け力が作用することにより鉄芯１０とヨーク２０とが継合される。
【００２５】
このように、第１の実施形態によれば、突片２３を弾性変形させて挿入穴２２の径を拡大させて鉄芯１０を挿入した後、突片２３の弾性復帰により鉄芯１０を締付け固定するという構成であるため、従来のかしめ加工方法や溶接加工方法に比べ、鉄芯１０、ヨーク２０に塑性ひずみが全く生じないため、磁気劣化がなく、安定した動作特性を確保できる。
【００２６】
更に、かしめ加工方法のようにスプリングバック等が鉄芯１０の軸方向に作用することがないため、鉄芯高さのバラツキも小さく、鉄芯１０とヨーク２０との位置関係を精度良く管理でき、電磁リレーとして適用した際、接点の初期状態を良好に維持できるという効果がある。
【００２７】
加えて、突片２３を外方に弾性変形により押し広げれば、鉄芯１０とヨーク２０との分解することができ、鉄芯１０とヨーク２０との再利用が可能となり、材料の有効利用が図れる。尚、本実施形態では、スリット２４を拡開させる操作を円滑に行なうために、突片２３を設けたが、フランジ部２１に挿入穴２２とスリット２４だけを設けた構成としても良い。
【００２８】
次いで、図４，図５は本発明方法の第２の実施形態を示すもので、図４に示すように、鉄芯１０の径に比べヨーク２０のフランジ部２１に開設されている挿入穴２２の径は鉄芯１０の径よりもやや大きめに設定されており、また、スリット２４のスリット幅も第１の実施形態よりは幅広に設定されていることが特徴である。
【００２９】
まず、図４に示すように、この大径の挿入穴２２内に鉄芯１０を挿入するが、鉄芯１０の挿入作業は、挿入穴２２が大径に設定されているため、作業は簡単に行なえる。その後、図５に示すように、スリット２４の左右側の突片２３を互いに接近させるように外部から力を加え、突片２３を塑性変形させる。
【００３０】
従って、スリット２４がほぼ閉鎖状態となるまで突片２３を突き合わせるため、挿入穴２２の径が縮小し、鉄芯１０を締め付けることになり、鉄芯１０を強固にヨーク２０に継合固定することができる。
【００３１】
このように、第２の実施形態によれば、磁性ひずみが生じるのは塑性変形するフランジ部２１の突片２３部分だけであり、フランジ部２１のその他の部位や鉄芯１０には何等塑性ひずみが生じないため、電磁石の磁気特性の劣化が生じることがなく、安定した動作特性が得られる。
【００３２】
また、かしめ加工等のように、鉄芯１０にスプリングバック等も発生しないため、鉄芯１０の高さのバラツキが小さく、第１の実施形態同様、電磁リレーとして使用した際には接点の初期状態を簡単に設定できるという有利さがある。
【００３３】
加えて、この第２実施形態においては、スリット２４のスリット幅を調整することにより、鉄芯１０の締付け力を任意に制御できるという利点もある。尚、この第２実施形態においても、突片２３を省略しても良く、その場合、磁性ひずみはスリット２４の近傍部分に分散する傾向にあるが、直接、磁路に悪影響を及ぼすものではなく、上述した作用効果が期待できる。
【００３４】
次いで、図６，図７は本発明方法の第３の実施形態を示すもので、基本的には第２の実施形態と同一であるが、ただ突片２３並びにスリット２４の形状に工夫が加えられている。すなわち、一方側の突片２３ａを他方側の突片２３ｂに対して延長し、更に先端を鉤状に折曲形成した鉤状部２５が設定されている。
【００３５】
従って、鉄芯１０の径よりも大径の挿入穴２２内に簡単に鉄芯１０を挿入した後、図６中矢印方向に突片２３ａ，２３ｂを塑性変形させることにより、図７に示すように、挿入穴２２の径を縮小させて鉄芯１０に締付け力を作用させ、ヨーク２０に対して鉄芯１０を堅固に継合固定できる。
【００３６】
そして、この実施形態によれば、鉄芯１０に塑性ひずみが生じることなく、安定した動作特性が得られるとともに、鉄芯１０とヨーク２０との取付公差の管理も容易であり、特に、一方側の突片２３ａに設けた鉤状部２５の先端が他方側の突片２３ｂに係止した状態となり、突片２３同士を拘束することにより、鉄芯１０の継合状態が緩むことがなく、堅固な継合構造を長期に亘り維持できるという有利さがある。
【００３７】
次いで、図８，図９は、本発明方法の第４の実施形態を示すもので、第２の実施形態の発展形である。すなわち、ヨーク２０のフランジ部２１に開設されている鉄芯１０よりも大径の挿入穴２２内に鉄芯１０を挿入した後、図９に示すように、スリット２０を挟んだ左右側の突片２３同士を互いに接近させるようにそれぞれ塑性変形させることにより、鉄芯１０に締付け力を働かせて、ヨーク２０に対して鉄芯１０を継合固定する。その後、突片２３同士の接合部位における端面、上面又は下面の隙間近傍部等適宜箇所にレーザー照射し、溶接部２６により突片２３同士の接合強度を高める。尚、溶接方法としては、上述したレーザー溶接の他に、抵抗溶接、アーク溶接、超音波溶接等の慣用の溶接方法を使用しても良い。
【００３８】
従って、磁路に関係ない突片２３部分で溶接加工が行なわれるため、鉄芯１０には塑性ひずみが全く発生せず、電磁石の安定した動作特性が得られ、上述した実施形態同様、鉄芯１０とヨーク２０との間で良好な取付精度も得られ、また、スリット２４の幅を任意に設定することにより、鉄芯１０の継合力を調整できるなどの有利さもある。
【００３９】
更に、図１０，図１１は本発明方法の第５の実施形態を示すもので、上述した実施形態と同様に、溶接加工を利用したものである。すなわち、鉄芯１０より大径の挿入穴２２内に鉄芯１０を挿入した後、スリット２４を閉鎖するように左右側の突片２３同士を図１０に示すように、矢印方向に塑性変形させる。
【００４０】
そして、このとき、スリット２４の形状は、基部側に比べ先端側が幅広に設定されており、フランジ部２１の塑性変形途中では、スリット２４は基部側が閉鎖したＶ字形状となっており、塑性加工の途中から、レーザを図中矢印Ｌで示すようにスリット２４の内側接触部の基部側から先端側に向けて、レーザの焦点を引きながら、塑性変形加工と同時にレーザ溶接を行なう（レーザの初期照射部位を図１０中符号Ｐで示す）。
【００４1】
したがって、図１１に示すように、溶接箇所がスリット２４の内側接触部であり、メッキ劣化箇所を閉じ込めることができるため錆の発生をおさえることができる。
【００４２】
さらに、スリット２４の幅が縮小する方向に、塑性加工を施しながら、スリット２４の全長に沿ってレーザ溶接を行なうことができるため、溶接強度を強化でき、鉄芯１０の継合強度を高めることができるという利点がある。
【００４３】
次いで、図１２，図１３は本発明方法の第６の実施形態を示すもので、基本的に本発明方法の第２実施形態の改良形である。すなわち、鉄芯１０より大径の挿入穴２２内に鉄芯１０を挿入した後、スリット２４を閉鎖するように左右側の突片２３を図１３に示すように矢印方向に塑性変形させることにより、鉄芯１０に締付け力を働かせて、ヨーク２０に対して鉄芯１０を継合するとともに、この継合状態を維持するとともに、リング状拘束部材２７を突片２３の外周に嵌め込むことで、スリット２４が拡開することがなく、鉄芯１０の強固な継合力を長期に亘り維持できる。
【００４４】
従って、この第６の実施形態においても、鉄芯１０に塑性ひずみが生じないことから、安定した動作特性が得られ、かつ鉄芯１０とヨーク２０との間の公差管理も容易なものとなり、しかも、スリット２４の幅を可変することにより、継合力を調整できるなどの効果を備えている。
【００４５】
また、図示はしないが、突片２３の先端をテーパー状に設定すれば、リング状拘束部材２７の嵌め込み作業も簡単に行なえるとともに、嵌め込み深さが深くなればなるほどリング状拘束部材２７の拘束力が増すため、鉄芯１０の強固な継合が得られるという付随的な利点もある。
【００４６】
次いで、本発明方法と従来方法（かしめ加工方法）とを比較して、図１４並びに表１を基に説明すると、図１４（ａ）のように、ヨーク２０の挿入穴２２にスリット幅Ｗのスリット２４を設け、鉄芯１０を挿入穴２２内に挿入する。そして、図１４（ｂ）のように、スリット２４の幅が狭まるようにプレスにて加圧し、固定した状態でスリット２４の先端をレーザーにて溶接加工を施す。図１４（ｃ）に示すように、磁路ａからはずれた部分のみに塑性ひずみｂが生じることから、かしめによる塑性ひずみｂに起因する鉄芯１０の磁気特性劣化が生じない。
【００４７】
スリット幅Ｗと鉄芯１０の保磁力Ｈｃ（Ｏｅ）、抜け荷重（ｋＮ）の関係を表１に示す。
【００４８】
【表１】

保磁力Ｈｃは鉄芯１０をかしめた後に、再度ヨーク２０から抜いた（分解した）鉄芯１０についてＨｃメーターにて測定した。抜け荷重は鉄芯１０を分解するのに必要な最大荷重を測定した。
【００４９】
従来の方式によるかしめの同様の評価では、保磁力Ｈｃは１．２７（Ｏｅ）、抜け荷重０．２６０（ｋＮ）を示すことがわかっており、本発明方法は従来方法に比べてかしめ強度はほぼ同等であるが、保磁力の劣化の程度が小さくなっているのがわかる。また、抜け荷重はスリット幅に関係なく安定することがわかる。
【００５０】
このように、本発明方法によれば、従来のものに比べ保磁力が半減しており、保磁力が小さければ小さいほど、安定した動作特性が得られるとともに、小さい電流で大きなパワーを現出させることができ、リレー装置をコンパクト化できるという有利さがある。
【００５１】
次いで、図１５のグラフで塑性ひずみによる磁気特性低下について磁性ひずみと磁束密度との関係を示す。図１５は、磁化Ｈが０．５から４０までの各Ｈで得られる磁束密度Ｂを区別して示している。
【００５２】
例えば、最下端に位置するＢ０．５（Ｈが０．５（Ｏｅ）のときのＢ）を見ると塑性ひずみを与えていないもの（塑性ひずみ０％）では磁束密度９０００（Ｇ）程度が得られるが、１％程度の塑性ひずみを与えると１０００（Ｇ）程度しか得られない。割合では９０％程度の低下を示している。どの曲線においても、わずかな塑性ひずみにて磁束密度の低下が確認でき、低磁場領域での磁束密度は特に顕著な低下を示している。
【００５３】
このように、かしめなどによって付与されるわずかな塑性ひずみによって磁気特性が大きく劣化することがわかっており、このことからも、本発明に係る電磁リレー用電磁石及びその製造方法の有用性が明らかである。
【００５４】
【発明の効果】
以上説明した通り、本発明によれば、鉄芯とヨークとの継合の際に磁気ひずみが生じることがないため、安定した動作特性が得られるとともに、保磁力も小さく抑えることができ、電磁リレーのコンパクト化を可能にするとともに、ヨークと鉄芯との取付位置の公差管理を容易なものにできるという効果を有する。
【図面の簡単な説明】
【図１】本発明に係る電磁リレー用電磁石に使用する鉄芯とヨークを示す分解斜視図である。
【図２】本発明に係る電磁石の製造方法の第１の実施形態における鉄芯の挿入前の状態を示す説明図である。
【図３】本発明に係る電磁石の製造方法の第１の実施形態における鉄芯の継合状態を示す説明図である。
【図４】本発明に係る電磁石の製造方法の第２の実施形態における鉄芯の挿入前の状態を示す説明図である。
【図５】本発明に係る電磁石の製造方法の第２実施形態における鉄芯の継合状態を示す説明図である。
【図６】本発明に係る電磁石の製造方法の第３の実施形態における鉄芯のヨークに対する挿入前の状態を示す説明図である。
【図７】本発明に係る電磁石の製造方法の第３の実施形態における鉄芯の継合状態を示す説明図である。
【図８】本発明に係る電磁石の製造方法の第４の実施形態における鉄芯の挿入前の状態を示す説明図である。
【図９】本発明に係る電磁石の製造方法の第４の実施形態における鉄芯の継合状態を示す説明図である。
【図１０】本発明に係る電磁石の製造方法の第５の実施形態におけるプレス加工とレーザー溶接加工工程を示す説明図である。
【図１１】本発明に係る電磁石の製造方法の第５の実施形態における鉄芯の継合状態を示す説明図である。
【図１２】本発明に係る電磁石の製造方法の第６の実施形態における鉄芯の挿入前の状態を示す説明図である。
【図１３】本発明に係る電磁石の製造方法の第６の実施形態における鉄芯の継合状態を示す説明図である。
【図１４】本発明に係る電磁石の製造方法を示す説明図である。
【図１５】磁性ひずみによる磁気特性低下を示すグラフである。
【図１６】電磁リレー用電磁石を示す斜視図である。
【図１７】電磁リレーを示す構成説明図である。
【図１８】電磁リレー用電磁石における従来の鉄芯とヨークとを示す斜視図である。
【図１９】ヨークに対する鉄芯の継合方法の従来例を示す説明図である。
【符号の説明】
１０鉄芯
２０ヨーク
２１フランジ部
２２挿入穴
２３（２３ａ，２３ｂ）突片
２４スリット
２５鉤状部
２６溶接部
２７リング状拘束部材[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an electromagnet for an electromagnetic relay and a method for manufacturing the same, and in particular, in a joining process between an iron core and a yoke, by suppressing magnetostriction, reliable operating characteristics can be obtained with a small current, and The present invention relates to an electromagnet for an electromagnetic relay that can easily manage tolerances with a yoke, and has improved accuracy in an initial state of a relay contact, and a manufacturing method thereof.
[0002]
[Prior art]
Usually, as shown in FIGS. 16 and 17, an electromagnet used for an electromagnetic relay is provided with a spool 3 attached to both end portions in the axial direction of an iron core 2 around which a coil 1 is wound, and a yoke 4 having an L-shaped cross section. It is attached to the flange part 5 and is comprised.
[0003]
Then, as shown in FIG. 17, when the electromagnet is energized, the iron core 2 attracts the movable iron piece 6 in the direction of arrow a, and when energization of the electromagnet is stopped, the spring means (not shown) causes the direction of arrow b. When the movable iron piece 6 operates, the contact is turned ON / OFF.
[0004]
By the way, as shown in FIG. 18, the connecting structure of the iron core 2 and the yoke 4 is formed by fitting the iron core 2 into the insertion hole 7 formed in the flange portion 5 of the yoke 4 and joining them. As a method for joining the core 2 and the yoke 4, a caulking method and a welding method are conventionally well known.
[0005]
First, as shown in FIG. 19, the caulking method is such that the diameter of the insertion hole 7 provided in the yoke 4 is set to be slightly larger than the diameter of the iron core 2, and the iron core 2 is inserted into the insertion hole 7. After the insertion, both ends in the axial direction of the iron core 2 are pressed by a press machine, thereby caulking the portion inserted through the insertion hole 7 and fixing the iron core 2 to the yoke 4.
[0006]
Although not shown in the figure, the welding method is to press-fit the iron core 2 into the insertion hole 7 of the yoke 4 and then to the yoke 4 by laser welding, resistance welding or the like along the insertion hole 7 on the lower surface of the flange portion 5. The iron core 2 is joined and fixed.
[0007]
[Problems to be solved by the invention]
However, in the joining method of the iron core and the yoke by the caulking method, since the iron core 2 and the yoke 4 use a soft magnetic material, a plastic strain is generated in the iron core 2 by caulking. was there.
[0008]
When plastic strain occurs, the magnetic properties tend to deteriorate greatly and the coercive force tends to increase. For example, when it is applied to an electromagnet for an electromagnetic relay, there is a drawback that a reliable ON / OFF switching cannot be expected due to a decrease in operating characteristics due to deterioration of magnetic characteristics. In addition, when the coercive force is increased, a large current is required for ON / OFF switching, and there is a drawback in that the compactness is hindered.
[0009]
Furthermore, in the caulking method, caulking is performed with a press machine. At that time, the height position of the iron core 2 cannot be accurately controlled by the spring back of the iron core 2, and the height position of the iron core 2 varies. There is a problem that management for reducing the variation and maintaining the initial state of the contact is very troublesome.
[0010]
On the other hand, in the welding method as well, there is a difficulty in the joint strength between the iron core 2 and the yoke 4, and there is a deterioration in magnetic properties caused by the gap between the insertion hole 7 and the iron core 2, Similarly, it has been pointed out that a stable operating characteristic cannot be obtained.
[0011]
The present invention has been made in view of such circumstances, so that stable operation characteristics can be obtained without causing plastic strain inside the iron core, and tolerance management of the mounting position of the iron core with respect to the yoke is simple and accurate. An object of the present invention is to provide an electromagnet for an electromagnetic relay that can easily ensure the initial state of the contact by performing well and a method for manufacturing the same.
[0012]
[Means for Solving the Problems]
The invention of this application is a method for manufacturing an electromagnet for an electromagnetic relay in which an iron core having a coil wound around its outer periphery is joined to an insertion hole provided in a flange portion of an L-shaped yoke. In this method of manufacturing an electromagnet for an electromagnetic relay, an insertion hole having a diameter slightly larger than the diameter of the iron core is formed in the flange portion of the yoke, and a slit is formed in communication between the insertion hole and the edge of the flange portion. With the steel core inserted into the insertion hole of the part, the flange part is plastically deformed so as to reduce the slit width, so that the iron core is tightened in the insertion hole, the iron core and the yoke are joined, and the flange part is joined. Is provided with projecting pieces on the left and right sides of the slit, and by deforming the projecting pieces in the joining direction, the slit width is reduced, and the iron core and the yoke are joined together. After extending the tip of the protruding piece in a bowl shape and plastically deforming the protruding pieces in the direction of reducing the slit width, the hook-shaped part and the protruding piece on the other side are locked, thereby Characterized by locking the joint state with the yoke Yes you.
[0013]
Therefore, according to the present invention, the iron core can be joined and fixed to the yoke by inserting the iron core into the insertion hole provided in the flange portion of the yoke and then plastically deforming the flange portion in the direction of reducing the slit width. In addition, plastic strain is generated only in the slit forming portion of the flange portion not related to the magnetic path, the plastic core does not generate any plastic strain, the electromagnet does not deteriorate in magnetic characteristics, and the iron core height is high. There is no variation in length. Further, if the slit width is set wide, the joining force between the iron core and the yoke can be controlled by the slit width, for example, the joining force of the iron core can be strengthened.
In addition, since the protrusions are formed on the left and right sides of the slit, it is only necessary to plastically deform the protrusions in the joining direction to reduce the slit width. It can be restricted only to the protruding piece part that is not related to Furthermore, after the projecting pieces are plastically deformed in the direction of reducing the slit width and the iron core is inserted into the insertion hole of the flange portion, the hook-shaped portion provided on the projecting piece on one side is locked to the projecting piece on the other side. If it does, opening of a slit can be prevented and the joint force of a yoke and an iron core can be maintained firmly over a long period of time.
[0014]
Further, in the method for manufacturing an electromagnet for an electromagnetic relay according to the present invention, a ring-shaped restraining member for restricting the opening of the slit is formed between the projecting pieces after plastically deforming the projecting pieces divided into two into the slits. It is characterized by being fitted and fixed.
[0015]
Therefore, according to the present invention, after the projecting pieces divided into two slits are plastically deformed inward, no plastic strain is generated. Therefore, there is no magnetic deterioration of the magnetic parts, and the magnetic characteristics of the electromagnet are deteriorated. Does not occur. Further, since the iron core can be separated without applying plastic strain by removing the ring-shaped restraining member, the iron core and the yoke can be reused.
[0016]
Furthermore, the method for manufacturing an electromagnet for an electromagnetic relay according to the present invention is characterized in that the projecting piece into which the ring-shaped restraining member is fitted is set in a tapered shape toward the tip.
[0017]
Therefore, according to the present invention, if the ring-shaped restraining member is inserted deeply into the projecting piece, the projecting pieces can be tightly joined to each other, and the joint force between the yoke and the iron core can be maintained firmly.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of an electromagnet for an electromagnetic relay according to the present invention and a manufacturing method thereof according to the present invention will be described below in detail with reference to the accompanying drawings.
[0019]
FIG. 1 is a perspective view showing an iron core and a yoke used in an electromagnet according to the present invention. FIGS. 2 and 3 are explanatory views showing a first embodiment of an electromagnet manufacturing method according to the present invention. 5 is an explanatory view showing a second embodiment of the method for manufacturing an electromagnet according to the present invention, FIG. 6 and FIG. 7 are explanatory views showing a third embodiment of the method for manufacturing an electromagnet according to the present invention, FIG. 9 is an explanatory view showing a fourth embodiment of the method for manufacturing an electromagnet according to the present invention, FIGS. 10 and 11 are explanatory views showing a fifth embodiment of the method for manufacturing an electromagnet according to the present invention, and FIGS. 13 is an explanatory view showing a sixth embodiment of an electromagnet manufacturing method according to the present invention, FIG. 14 is an explanatory view showing the operation of the fourth embodiment, and FIG. 15 is a graph showing a decrease in magnetic characteristics due to magnetic strain. .
[0020]
In addition, about the general structure of an electromagnet, since what is shown to FIG. 16, FIG. 17 of a prior art example is used, detailed description is abbreviate | omitted here.
[0021]
In FIG. 1, the structure of the iron core 10 and the yoke 20 is demonstrated. A coil is wound around the outer periphery of the iron core 10 and spools are attached to both ends of the iron core 10 in the axial direction. In the present invention, the structure of the iron core 10 and the yoke 20 and the joining method are used. Since there is a feature, it is omitted here. Reference numeral 10 denotes an iron core made of a soft magnetic material. A disk-shaped flange 11 is formed on the opposite side of the insertion end of the iron core 10.
[0022]
On the other hand, the yoke 20 is also made of a soft magnetic material and is composed of a plate member having an L-shaped cross section having a flange portion 21. An insertion hole 22 for the iron core 10 is opened at the center of the flange portion 21. A projecting piece 23 projecting outward is projected from the tip edge of 21, and a slit 24 is formed in communication with the insertion hole 22 so as to divide the projecting piece 23 into left and right parts. Therefore, a feature is that a pair of projecting pieces 23 are integrally formed on the flange portion 21 on both sides of the slit 24 so that the diameter of the insertion hole 22 can be varied by the slit 24.
[0023]
Next, a method for joining the iron core 10 and the yoke 20 will be described with reference to FIG. First, in the first embodiment of the present invention, the diameter of the insertion hole 22 provided in the flange portion 21 of the yoke 20 is set to be smaller than the diameter of the iron core 10.
[0024]
Therefore, in order to insert the iron core 10 into the insertion hole 22 of the yoke 20, as shown in FIG. 2, the projecting piece 23 is expanded to the left and right in the direction of the arrow in the figure, and the slit 24 is expanded to insert the insertion hole 22. When the external force applied to the projecting piece 23 is released after the iron core 10 is inserted and the projecting piece 23 returns to the original position, as shown in FIG. When the diameter of the insertion hole 22 is reduced and a tightening force is applied to the iron core 10, the iron core 10 and the yoke 20 are joined together.
[0025]
As described above, according to the first embodiment, after the protruding piece 23 is elastically deformed to increase the diameter of the insertion hole 22 and the iron core 10 is inserted, the iron core 10 is tightened by elastic return of the protruding piece 23. Since the structure is fixed, plastic distortion does not occur at all in the iron core 10 and the yoke 20 as compared with the conventional caulking method and welding method, so that there is no magnetic deterioration and stable operating characteristics can be ensured.
[0026]
Furthermore, unlike the caulking method, the springback or the like does not act in the axial direction of the iron core 10, so the variation in the iron core height is small, and the positional relationship between the iron core 10 and the yoke 20 can be managed with high accuracy. When applied as an electromagnetic relay, there is an effect that the initial state of the contact can be maintained satisfactorily.
[0027]
In addition, if the protruding piece 23 is spread outward by elastic deformation, the iron core 10 and the yoke 20 can be disassembled, and the iron core 10 and the yoke 20 can be reused. I can plan. In the present embodiment, the protruding piece 23 is provided in order to smoothly perform the operation of expanding the slit 24. However, the flange portion 21 may be provided with only the insertion hole 22 and the slit 24.
[0028]
4 and 5 show a second embodiment of the method of the present invention. As shown in FIG. 4, the insertion hole 22 formed in the flange portion 21 of the yoke 20 compared to the diameter of the iron core 10. The diameter is set to be slightly larger than the diameter of the iron core 10, and the slit width of the slit 24 is also set to be wider than that of the first embodiment.
[0029]
First, as shown in FIG. 4, the iron core 10 is inserted into the large-diameter insertion hole 22. The insertion operation of the iron core 10 is easy because the insertion hole 22 is set to a large diameter. It can be done. After that, as shown in FIG. 5, a force is applied from the outside so that the left and right protruding pieces 23 of the slit 24 approach each other, and the protruding pieces 23 are plastically deformed.
[0030]
Therefore, since the projecting piece 23 is abutted until the slit 24 is almost closed, the diameter of the insertion hole 22 is reduced, the iron core 10 is tightened, and the iron core 10 is firmly fixed to the yoke 20. be able to.
[0031]
As described above, according to the second embodiment, the magnetic strain is generated only in the projecting piece 23 portion of the flange portion 21 that is plastically deformed, and the other portions of the flange portion 21 and the iron core 10 are not subjected to any plastic strain. Therefore, the magnetic characteristics of the electromagnet are not deteriorated, and stable operating characteristics can be obtained.
[0032]
In addition, unlike the caulking process or the like, no springback or the like is generated in the iron core 10, so that the variation in the height of the iron core 10 is small, and, as in the first embodiment, the initial contact point when used as an electromagnetic relay. There is an advantage that the state can be easily set.
[0033]
In addition, the second embodiment has an advantage that the tightening force of the iron core 10 can be arbitrarily controlled by adjusting the slit width of the slit 24. In the second embodiment, the projecting piece 23 may be omitted. In this case, the magnetic strain tends to be distributed in the vicinity of the slit 24, but does not directly affect the magnetic path. The effects described above can be expected.
[0034]
Next, FIG. 6 and FIG. 7 show a third embodiment of the method of the present invention, which is basically the same as the second embodiment, but only the shape of the protruding piece 23 and the slit 24 is devised. It has been. That is, a hook-like portion 25 is set in which one protrusion piece 23a is extended with respect to the other protrusion piece 23b and the tip is bent into a hook shape.
[0035]
Accordingly, after the iron core 10 is simply inserted into the insertion hole 22 having a diameter larger than the diameter of the iron core 10, the projecting

pieces

23a and 23b are plastically deformed in the direction of the arrow in FIG. Further, the diameter of the insertion hole 22 can be reduced to apply a tightening force to the iron core 10, so that the iron core 10 can be firmly joined and fixed to the yoke 20.
[0036]
According to this embodiment, stable operating characteristics can be obtained without causing plastic strain in the iron core 10, and management of mounting tolerances between the iron core 10 and the yoke 20 is easy. The end of the hook-shaped portion 25 provided on the protruding piece 23a is locked to the protruding piece 23b on the other side, and by restraining the protruding pieces 23, the joined state of the iron core 10 is not loosened. There is an advantage that a firm joint structure can be maintained over a long period of time.
[0037]
Next, FIG. 8 and FIG. 9 show a fourth embodiment of the method of the present invention, which is a development of the second embodiment. That is, after the iron core 10 is inserted into the insertion hole 22 having a diameter larger than that of the iron core 10 provided in the flange portion 21 of the yoke 20, as shown in FIG. By causing the pieces 23 to be plastically deformed so as to approach each other, a tightening force is applied to the iron core 10 to jointly fix the iron core 10 to the yoke 20. Thereafter, laser irradiation is applied to an appropriate portion such as a gap near the end surface, the upper surface, or the lower surface of the joining portion between the projecting pieces 23, and the joining strength between the projecting pieces 23 is increased by the welded portion 26. As a welding method, in addition to the laser welding described above, a conventional welding method such as resistance welding, arc welding, or ultrasonic welding may be used.
[0038]
Therefore, since welding is performed at the projecting piece 23 portion that is not related to the magnetic path, the iron core 10 is not subjected to plastic strain at all, and stable operation characteristics of the electromagnet can be obtained. Good attachment accuracy is also obtained between the yoke 10 and the yoke 20, and there is an advantage that the joining force of the iron core 10 can be adjusted by arbitrarily setting the width of the slit 24.
[0039]
Further, FIGS. 10 and 11 show a fifth embodiment of the method of the present invention, which uses welding as in the above-described embodiment. That is, after inserting the iron core 10 into the insertion hole 22 having a diameter larger than that of the iron core 10, the left and right projecting pieces 23 are plastically deformed in the direction of the arrow as shown in FIG. .
[0040]
At this time, the shape of the slit 24 is set wider on the tip side than on the base side, and the slit 24 is V-shaped with the base side closed in the middle of plastic deformation of the flange portion 21. In the middle of the laser beam, laser welding is performed simultaneously with plastic deformation while the laser is focused from the base side to the tip side of the inner contact portion of the slit 24 as indicated by an arrow L in the figure (laser initial stage). An irradiation site is indicated by a symbol P in FIG. 10).
[0041]
Therefore, as shown in FIG. 11, the welding location is the inner contact portion of the slit 24, and the plating degradation location can be confined, so that generation of rust can be suppressed.
[0042]
Furthermore, since laser welding can be performed along the entire length of the slit 24 while performing plastic working in the direction in which the width of the slit 24 is reduced, the welding strength can be enhanced and the joint strength of the iron core 10 can be increased. There is an advantage that can be.
[0043]
12 and 13 show a sixth embodiment of the method of the present invention, which is basically an improved version of the second embodiment of the method of the present invention. That is, by inserting the iron core 10 into the insertion hole 22 having a diameter larger than that of the iron core 10, the left and right projecting pieces 23 are plastically deformed in the direction of the arrow as shown in FIG. 13 so as to close the slit 24. By applying a tightening force to the iron core 10 to join the iron core 10 to the yoke 20 and maintaining this joined state, the ring-shaped restraining member 27 is fitted on the outer periphery of the projecting piece 23. The slit 24 does not expand, and the strong joining force of the iron core 10 can be maintained for a long time.
[0044]
Accordingly, even in the sixth embodiment, since plastic distortion does not occur in the iron core 10, stable operation characteristics can be obtained, and tolerance management between the iron core 10 and the yoke 20 can be easily performed. In addition, by changing the width of the slit 24, the effect of adjusting the joining force is provided.
[0045]
Although not shown, if the tip of the projecting piece 23 is set in a tapered shape, the ring-shaped restraining member 27 can be easily fitted, and the ring-like restraining member 27 is restrained as the fitting depth increases. Since the force increases, there is also an attendant advantage that a strong joint of the iron core 10 can be obtained.
[0046]
Next, the method of the present invention is compared with the conventional method (caulking method) and will be described with reference to FIG. 14 and Table 1. As shown in FIG. A slit 24 is provided, and the iron core 10 is inserted into the insertion hole 22. Then, as shown in FIG. 14B, pressurization is performed by a press so that the width of the slit 24 is narrowed, and the tip of the slit 24 is welded by laser in a fixed state. As shown in FIG. 14C, since the plastic strain b is generated only in the portion deviated from the magnetic path a, the magnetic characteristics of the iron core 10 are not deteriorated due to the plastic strain b due to caulking.
[0047]
Table 1 shows the relationship between the slit width W, the coercive force Hc (Oe) of the iron core 10, and the removal load (kN).
[0048]
[Table 1]

The coercive force Hc was measured with an Hc meter on the iron core 10 that was pulled out (decomposed) from the yoke 20 after caulking the iron core 10. The maximum load required for disassembling the iron core 10 was measured.
[0049]
In a similar evaluation of caulking by the conventional method, it is known that the coercive force Hc is 1.27 (Oe) and the removal load is 0.260 (kN), and the caulking strength of the method of the present invention is higher than that of the conventional method. Although it is almost the same, it can be seen that the degree of degradation of the coercive force is small. Further, it can be seen that the pull-out load is stable regardless of the slit width.
[0050]
As described above, according to the method of the present invention, the coercive force is halved compared to the conventional one, and the smaller the coercive force, the more stable operation characteristics can be obtained, and a large power can be produced with a small current. There is an advantage that the relay device can be made compact.
[0051]
Next, the graph of FIG. 15 shows the relationship between the magnetic strain and the magnetic flux density with respect to the decrease in magnetic properties due to plastic strain. FIG. 15 separately shows the magnetic flux density B obtained at each magnetization H of 0.5 to 40.
[0052]
For example, looking at B0.5 (B when H is 0.5 (Oe)) located at the lowermost end, a magnetic flux density of about 9000 (G) is obtained with no plastic strain (plastic strain 0%). However, when a plastic strain of about 1% is applied, only about 1000 (G) can be obtained. The ratio shows a decrease of about 90%. In any curve, a decrease in the magnetic flux density can be confirmed with a slight plastic strain, and the magnetic flux density in the low magnetic field region shows a particularly remarkable decrease.
[0053]
As described above, it is known that the magnetic characteristics are greatly deteriorated by slight plastic strain applied by caulking or the like, and this also reveals the usefulness of the electromagnet for electromagnetic relay and the manufacturing method thereof according to the present invention. is there.
[0054]
【The invention's effect】
As described above, according to the present invention, no magnetostriction occurs when the iron core and the yoke are joined, so that stable operating characteristics can be obtained, and the coercive force can be kept small. The relay can be made compact, and the tolerance management of the mounting position between the yoke and the iron core can be easily managed.
[Brief description of the drawings]
FIG. 1 is an exploded perspective view showing an iron core and a yoke used in an electromagnet for an electromagnetic relay according to the present invention.
FIG. 2 is an explanatory view showing a state before the iron core is inserted in the first embodiment of the electromagnet manufacturing method according to the present invention.
FIG. 3 is an explanatory view showing an iron core joining state in the first embodiment of the electromagnet manufacturing method according to the present invention.
FIG. 4 is an explanatory view showing a state before insertion of an iron core in a second embodiment of the electromagnet manufacturing method according to the present invention.
FIG. 5 is an explanatory view showing an iron core joining state in the second embodiment of the electromagnet manufacturing method according to the present invention.
FIG. 6 is an explanatory view showing a state before the iron core is inserted into the yoke in the third embodiment of the electromagnet manufacturing method according to the present invention.
FIG. 7 is an explanatory view showing a joining state of iron cores in a third embodiment of an electromagnet manufacturing method according to the present invention.
FIG. 8 is an explanatory view showing a state before insertion of an iron core in a fourth embodiment of an electromagnet manufacturing method according to the present invention.
FIG. 9 is an explanatory view showing a joining state of iron cores in a fourth embodiment of an electromagnet manufacturing method according to the present invention.
FIG. 10 is an explanatory diagram showing press working and laser welding processing steps in a fifth embodiment of a method for producing an electromagnet according to the present invention.
FIG. 11 is an explanatory view showing a joining state of iron cores in a fifth embodiment of an electromagnet manufacturing method according to the present invention.
FIG. 12 is an explanatory diagram showing a state before insertion of an iron core in a sixth embodiment of an electromagnet manufacturing method according to the present invention.
FIG. 13 is an explanatory view showing an iron core joining state in a sixth embodiment of a method of manufacturing an electromagnet according to the present invention.
FIG. 14 is an explanatory view showing a method for manufacturing an electromagnet according to the present invention.
FIG. 15 is a graph showing a decrease in magnetic characteristics due to magnetic strain.
FIG. 16 is a perspective view showing an electromagnet for an electromagnetic relay.
FIG. 17 is a configuration explanatory view showing an electromagnetic relay.
FIG. 18 is a perspective view showing a conventional iron core and yoke in an electromagnet for an electromagnetic relay.
FIG. 19 is an explanatory view showing a conventional example of a method for joining an iron core to a yoke.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 Iron core 20 Yoke 21 Flange part 22 Insertion hole 23 (23a, 23b) Projection piece 24 Slit 25 Gutter-like part 26 Welding part 27 Ring-shaped restraint member

Claims

外周にコイルを巻装した鉄芯の一端を断面Ｌ字状のヨークのフランジ部に設けた挿入穴に継合する電磁リレー用電磁石の製造方法において、
ヨークのフランジ部に鉄芯の径よりやや大径の挿入穴が開設され、該挿入穴とフランジ部の端縁との間にスリットが連通形成され、フランジ部の挿入穴に鉄芯を挿入した状態でスリット幅を縮小させるようにフランジ部を塑性変形させることにより、鉄芯を挿入穴内で締め付け、鉄芯とヨークとを継合させ、かつ
フランジ部には、スリットを境とした左右側に突片が設けられ、突片同士を接合方向に塑性変形させることにより、スリット幅を縮小させて、鉄芯とヨークとの継合を行い、さらに
一方側の突片の先端を鉤状に延設し、突片同士をスリット幅の縮小方向に塑性変形させた後、上記鉤状部と他方側の突片とを係止させることにより、鉄芯とヨークとの継合状態をロックしたことを特徴とする電磁リレー用電磁石の製造方法。In the method for producing an electromagnet for an electromagnetic relay in which one end of an iron core having a coil wound on the outer periphery is joined to an insertion hole provided in a flange portion of an L-shaped yoke,
An insertion hole with a diameter slightly larger than the diameter of the iron core was established in the flange portion of the yoke, a slit was formed in communication between the insertion hole and the edge of the flange portion, and the iron core was inserted into the insertion hole of the flange portion. By plastically deforming the flange part so as to reduce the slit width in the state, the iron core is tightened in the insertion hole, the iron core and the yoke are joined, and the flange part is on the left and right sides with the slit as a boundary. Projections are provided, and the projecting pieces are plastically deformed in the joining direction to reduce the slit width, join the iron core and the yoke, and extend the tip of the projecting piece on one side into a bowl shape. After the projecting pieces were plastically deformed in the direction of decreasing the slit width, the joining state between the iron core and the yoke was locked by locking the hook-shaped part and the projecting piece on the other side. A method for producing an electromagnet for an electromagnetic relay.

外周にコイルを巻装した鉄芯の一端を断面Ｌ字状のヨークのフランジ部に設けた挿入穴に継合する電磁リレー用電磁石の製造方法において、
ヨークのフランジ部に鉄芯の径よりやや大径の挿入穴が開設され、該挿入穴とフランジ部の端縁との間にスリットが連通形成され、フランジ部の挿入穴に鉄芯を挿入した状態でスリット幅を縮小させるようにフランジ部を塑性変形させることにより、鉄芯を挿入穴内で締め付け、鉄芯とヨークとを継合させ、かつ
フランジ部には、スリットを境とした左右側に突片が設けられ、突片同士を接合方向に塑性変形させることにより、スリット幅を縮小させて、鉄芯とヨークとの継合を行い、さらに
スリットに２分割される突片同士を内方に向けて塑性変形させた後、スリットの開きを規制するリング状拘束部材を突片同士に嵌め込み固着することを特徴とする電磁リレー用電磁石の製造方法。In the method for producing an electromagnet for an electromagnetic relay in which one end of an iron core having a coil wound on the outer periphery is joined to an insertion hole provided in a flange portion of an L-shaped yoke,
An insertion hole with a diameter slightly larger than the diameter of the iron core was established in the flange portion of the yoke, a slit was formed in communication between the insertion hole and the edge of the flange portion, and the iron core was inserted into the insertion hole of the flange portion. By plastically deforming the flange part so as to reduce the slit width in the state, the iron core is tightened in the insertion hole, the iron core and the yoke are joined, and the flange part is on the left and right sides with the slit as a boundary. Protruding pieces are provided, and the projecting pieces are plastically deformed in the joining direction to reduce the slit width, to connect the iron core and the yoke, and to further separate the protruding pieces that are divided into two into the slits. A method of manufacturing an electromagnet for an electromagnetic relay, comprising: a ring-shaped restraining member that restricts the opening of a slit is fitted into and fixed to protrusions after being plastically deformed toward the surface.

リング状拘束部材を嵌め込む突片は、先端に向けてテーパー状に設定されていることを特徴とする請求項２に記載の電磁リレー用電磁石の製造方法。 The method of manufacturing an electromagnet for an electromagnetic relay according to claim 2, wherein the projecting piece into which the ring-shaped restraining member is fitted is set in a tapered shape toward the tip.