JP2004253508A

JP2004253508A - Fixing structure and fixing method of large-size surface mounting component

Info

Publication number: JP2004253508A
Application number: JP2003040676A
Authority: JP
Inventors: Toshihiko Fujii; 俊彦冨士井
Original assignee: Denso Ten Ltd
Current assignee: Denso Ten Ltd
Priority date: 2003-02-19
Filing date: 2003-02-19
Publication date: 2004-09-09

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fixing method of large-size surface mounting component which can realize improvement in quality and cost reduction of an electronic apparatus including large-size surface mounting components. <P>SOLUTION: The fixing structure of large-size surface mounting component in which large-size surface mounting components are mounted over a substrate with the reflow soldering process comprises eyelets, which are inserted into the fixing holes formed on the substrate, the fixing holes formed to the large-size surface mounting components and holes of the substrate and large-size surface mounting components and are fixed by expanding the projected portions from any of the end surfaces and screws, which are inserted into the eyelets fixed to the substrate and large-size surface mounting components. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

【０００１】
【発明の属する技術分野】
本発明は基板に実装される大型表面実装部品の固定構造及び大型表面実装部品の固定方法に関する。
【０００２】
【従来の技術】
従来の大型表面実装部品の固定構造を図５および図６を用いて説明する。
【０００３】
図５は従来の実装基板の組立工程を示す概略図で、（ａ）大型表面実装コネクタ搭載状態、（ｂ）ねじ締め状態（リフローはんだ付け前）、（ｃ）リフローはんだ付け後、（ｄ）ねじ締め直し後の図である。図６は従来の実装基板と放熱板の組立工程を示す概略図で、（ａ）締結前、（ｂ）締結後の図である。
【０００４】
５０は大型表面実装コネクタ６０を有する電子機器の一部で、図６で示すように実装基板５５、放熱板６５およびねじ５１、５２などにより構成されている。
【０００５】
実装基板５５は、図５で示すように基板５６、大型表面実装コネクタ６０およびねじ５１などにより構成されている。
【０００６】
基板５６はアルミ基板で、アルミ板の表面が樹脂部材にて電気的に絶縁されており、表面には電子回路を形成する接続回路が形成され、接続回路の所定の位置には電子部品（図示省略）を実装するパターンや大型表面実装コネクタ６０の電極の実装パターン（いずれも図示省略）などが形成されている。その他に、大型表面実装コネクタ６０の位置決孔５７および大型表面実装コネクタ６０を取り付けるねじ孔５８や放熱板６５に取り付ける孔５９などが形成されている。
【０００７】
放熱板６５は、図６で示すように基板５６に実装された発熱型電子部品の熱を外部へ放出する部品で、実装基板５５を取り付けるねじ孔６６およびねじ５１の逃げ孔６７や位置決ピン６１の逃げ孔６８などが形成されている。放熱板６５の材料には軽くて熱伝導性のよいアルミ部材などが用いられる。
【０００８】
先ず、実装基板５５の組立について図５を用いて説明する。
【０００９】
実装基板５５を組み立てるには、先ず、基板５６の電子部品実装位置のパターン部に、はんだペーストを印刷（塗布）する。次に、塗布されたはんだペースト（図示省略）の上に小型の電子部品を搭載（機械実装）する。この状態において、大型表面実装コネクタ６０の実装面から突出した位置決ピン６１を基板５６に形成された位置決孔５７に挿入し、先に塗布されたはんだペーストの上に大型表面実装コネクタ６０の電極（図示省略）を位置決めする。次に、大型表面実装コネクタ６０に設けられた孔６２と基板５６に形成されたねじ孔５９とを合わせ、ねじ５１を挿通し締め付けて大型表面実装コネクタ６０を基板５６に固定する。この状態で高温の炉内を通過させ、はんだペーストを溶かして小型の電子部品と大型表面実装コネクタ６０の端子とを、それぞれのパターン部にはんだ付け（リフローはんだ付け）する。
【００１０】
次に、実装基板と放熱板の組立について図６を用いて説明する。
【００１１】
実装基板５５と放熱板６５（電子機器５０）を組み立てるには、先に組み立てた実装基板５５の基板５６に形成された孔５９と放熱板６５に形成されたねじ孔６６とを合わせ、ねじ５２を挿入して締め付け、基板５６と放熱板６５とを固定して電子機器５０の一部が完成する。
【００１２】
この出願の発明に関する先行技術文献としては次のものがある。
【００１３】
【特許文献１】
実公平７−３０４９号公報（第５−７頁、第１図）
【特許文献２】
実公平７−５５３７４号公報（第５−７頁、第１図）
【特許文献３】
実公平８−４５５８２号公報
【００１４】
【発明が解決しようとする課題】
しかし、上述の電子機器５０の構造では、大型表面実装コネクタ６０を基板５６に固定する際にねじ５１により締め付けるので、ねじ締め時の振動が、先にはんだペースト上に搭載した小型の電子部品に伝わり位置ずれが発生する。この状態でリフローはんだ付けが行われると、小型の電子部品が所定の位置からずれてはんだ付けされ、隣接する電子部品などに接触するなどの不具合につながる。また、リフローはんだ付け時の熱により大型表面実装コネクタ６０を固定しているねじ５１の当接部の樹脂が軟化して変形し、図５（ｃ）で示すように熱変形部６３ができる。その結果、ねじ５１の締付力が不十分となる場合があるので、図５（ｄ）で示すようにリフローはんだ付け後にねじ５１の締め直し（増し締め）が必要となり作業効率が低下する。
【００１５】
尚、上述の先行技術文献の特許文献１および特許文献２に開示されたものは、比較的に大きな物の締結には適しているが、本発明のように電子部品への適用には大きさ、品質面およびコスト面などにおいて適用するには構造上に無理がある。また、特許文献３に開示されたものは、本発明のように基板の裏面側に当接する放熱部材に締結する場合には、所定の位置に取付孔を設けることになるので、取付孔の分だけ基板の実装密度の減少につながるおそれがある。
【００１６】
本発明は上述の問題を解決するもので、大型表面実装部品を有する電子機器の品質向上とコスト低減が図れる大型表面実装部品の固定構造を提供することを目的とする。
【００１７】
【課題を解決するための手段】
本発明は上述の目的を達成するもので、基板に、リフローはんだ付けにより大型表面実装部品を実装する大型表面実装部品の固定構造において、前記基板に形成された固定用の孔と、前記大型表面実装部品に形成された固定用の孔と、前記基板と前記大型表面実装部品との孔に挿通し、少なくともいずれか一方の端面からの突出部分を押し拡げて固定する筒状固定部品と、前記基板と前記大型表面実装部品に固定された前記筒状固定部品に挿通される締結部材とからなることを特徴とするものである。
【００１８】
また、前記締結部材により前記基板の裏面側に構成される基板裏面側部材が締結されることを特徴とするものである。
【００１９】
また、前記締結部材には、ねじが用いられ前記基板裏面側部材には該ねじに螺合するねじ孔が形成されていることを特徴とするものである。
【００２０】
また、前記締結部材には、ハトメまたは筒状部材が用いられ少なくとも一方の端部または両端部を押し拡げて締結することを特徴とするものである。
【００２１】
また、前記締結部材には、リベットまたは棒状部材が用いられ少なくとも一方の端部または両端部を押潰して締結することを特徴とするものである。
【００２２】
また、前記締結部材には、樹脂製のリベットまたは棒状部材が用いられ少なくとも一方の端部または両端部を熱圧着して締結することを特徴とするものである。
【００２３】
また、前記基板裏面側部材が放熱板であることを特徴とするものである。
【００２４】
また、前記基板裏面側部材が筐体であることを特徴とするものである。
【００２５】
また、はんだペーストが塗布された基板に、大型表面実装部品を搭載する工程と、前記基板と前記大型表面実装部品とを筒状固定部品で固定する工程と、前記基板と前記大型表面実装部品とをリフローはんだ付けする工程とからなることを特徴とするものである。
【００２６】
また、前記リフローはんだ付け工程後に、前記筒状固定部品の孔に締結部材を挿通して締結する工程を含むことを特徴とするものである。
【００２７】
また、前記締結工程では、前記基板と前記大型表面実装部品と前記基板の裏面側に構成される基板裏面側部材とを一緒に締結することを特徴とするものである。
【００２８】
また、はんだペーストが塗布された基板に、大型表面実装部品を搭載する工程と、前記基板と前記大型表面実装部品とを筒状固定部品で固定する工程と、前記基板と前記大型表面実装部品とをリフローはんだ付けする工程と、前記リフローはんだ付け工程後に前記筒状固定部品の固定部の修正工程とからなることを特徴とするものである。
【００２９】
【発明の実施の形態】
本発明の大型表面実装部品の固定構造を適用した電子機器の事例について図を用いて説明する。
【００３０】
先ず、第１実施の形態を図１および図２を用いて説明する。
【００３１】
図１は本発明の第１実施の形態に係る実装基板の組立工程を示す概略図で、（ａ）大型表面実装コネクタ搭載状態、（ｂ）ハトメかしめ（固定）後、（ｃ）リフローはんだ付け後、（ｄ）ハトメかしめ部修正後の図である。図２は本発明に係る実装基板と放熱板の組立工程を示す概略図で、（ａ）締結前、（ｂ）締結後の図である。
【００３２】
１０は大型表面実装コネクタ３０を有する電子機器の一部で、図２で示すように実装基板２０、放熱板３５およびねじ１６などにより構成されている。
【００３３】
実装基板２０は、図１で示すように基板２１、大型表面実装コネクタ３０およびハトメ１４などにより構成されている。
【００３４】
基板２１はアルミ基板で、図１で示すようにアルミ板の表面が樹脂部材にて電気的に絶縁されており、表面には電子回路を形成する接続回路が形成され、接続回路の所定の位置には電子部品（図示省略）を実装するパターンや大型表面実装コネクタ３０の電極の実装パターン（いずれも図示省略）などが形成されている。その他に、大型表面実装コネクタ３０の位置決孔２２およびハトメ挿入孔２３などが形成されている。
【００３５】
放熱板３５（固定物に相当）は、図２で示すように基板２１に実装された発熱型電子部品の熱を外部へ放出する部品で、実装基板２０を取り付けるねじ孔３６およびハトメのかしめ部の逃げ孔３７や位置決ピン３１の逃げ孔３８などが形成されている。放熱板３５の材料には軽くて熱伝導性のよいアルミ部材などが用いられる。
【００３６】
先ず、実装基板２０の組立について図１を用いて説明する。
【００３７】
実装基板２０を組み立てるには、先ず、基板２１の電子部品実装位置のパターン部に、はんだペーストを印刷（塗布）する。次に、塗布されたはんだペースト（図示省略）の上に小型の電子部品を搭載（機械実装）する。この状態において、大型表面実装コネクタ３０の実装面から突出した位置決ピン３１を、基板２１に形成された位置決孔２２に挿入し、先に塗布されたはんだペーストの上に大型表面実装コネクタ３０の電極（図示省略）を位置決めする。次に、大型表面実装コネクタ３０に設けられた孔３２と基板２１に形成されたハトメ挿入孔２３とを合わせ、ハトメ１４（例えば、所定の長さに切断されたアルミや黄銅などの金属製の筒の一方を外側方向へ傘状に押し拡げている）を挿通する。そして、ハトメ１４の突出部分をかしめ（押し拡げる）て大型表面実装コネクタ３０を基板２１に固定する。この状態で高温の炉内を通過させ、はんだペーストを溶かして小型の電子部品と大型表面実装コネクタ３０の端子とを、それぞれのパターンにはんだ付け（リフローはんだ付け）して実装基板２０とする。
【００３８】
尚、ハトメ１４のかしめ状態を基板２１と大型表面実装コネクタ３０との当接面が離れないように仮止め程度にかしめることにより、かしめ時に発生する振動がさらに減少し、搭載された小型の電子部品のずれをさらに少なくする効果がある。但し、基板２１と大型表面実装コネクタ３０との固定力が弱まるので、基板２１の裏面側にハトメ１４の孔１５を利用して締結する部材がなく、実装基板２０をそのままの状態で使用する場合には、図１（ｄ）で示すようにハトメ１４のかしめ部を必要によりかしめ直す修正工程を追加してもよい。
【００３９】
次に、実装基板と放熱板の組立について図２を用いて説明する。
【００４０】
実装基板２０と放熱板３５を組み立てるには、先に組み立てた実装基板２０のハトメ１４の孔１５と放熱板３５に形成されたねじ孔３６とを合わせ、ハトメ１４の孔１５にねじ１６を挿入して締め付け、大型表面実装コネクタ３０と基板２１と放熱板３５とをサンドイッチ状に締結して電子機器１０の一部が完成される。
【００４１】
以上説明したように本発明の第１実施の形態に係る電子機器１０によれば、大型表面実装コネクタ３０と基板２１とを固定するのに、ハトメ１６を用いることにより、ハトメ１４のかしめ時に、軸芯方向に加わる力が主となり、従来例のねじ締結に比べ振動の発生が少なくなるので、はんだペーストの上に搭載されたリフローはんだ付け前の電子部品に加わる振動を少なくすることができる。したがって、電子部品が振動により当所の搭載位置から移動するのを防止することができ、所定の位置にはんだ付けすることができるので品質の向上が図れる。
【００４２】
また、ハトメ１４の孔１５を活用してねじ１６を挿入して実装基板２０と放熱板３５とを締結するので、リフローはんだ付け時の熱により大型表面実装コネクタ３０を固定しているハトメ１４の当接部の樹脂に、図１（ｃ）に示すように熱変形部３３ができ、ハトメ１４のかしめ部に緩みが発生する場合がある。しかし、次の組立工程でねじ１６により締めつけられ緩みが修正されるので、余分な工数を必要とせず品質の向上と作業効率が向上しコスト低減が図れる。
【００４３】
尚、本例では本発明の大型表面実装コネクタ３０と基板２１との固定にハトメ１４を用いたが、これに限らずハトメ１４の替わりに例えば、所定の長さに切断されたアルミや黄銅などの筒を用い、大型表面実装コネクタ３０と基板２１から突出した両側をかしめて（押し拡げて）大型表面実装コネクタ３０を基板２１に固定することもできる。アルミや黄銅の筒を用いればハトメ１４に比べ安価なのでコスト低減が図れる。
【００４４】
次に、第２実施の形態を図３を用いて説明する。図３は本発明の第２実施の形態に係る大型表面実装コネクタを有する電子機器の一部を示す概略図で、（ａ）締結前、（ｂ）締結後の図である。尚、第２実施の形態は第１実施の形態の締結部を除き第１実施の形態と同じであるので、同じ構成については同じ符号を付し変更部分を重点に説明しその他については説明を省略する。
【００４５】
電子機器１１は、実装基板２０、放熱板３５およびハトメ１７などにより構成されている。
【００４６】
放熱板３５には、実装基板２０のハトメ１４の孔１５と対応する位置に、孔１５と略同じ大きさのハトメ挿入孔３９が設けられており、電子機器１１を組み立てるには、実装基板２０のハトメ１４の孔１５と放熱板３５のハトメ挿入孔３９とを合わせ、例えばアルミや黄銅で形成されたハトメ１７を挿入する。そして、ハトメ１７の突出部分をかしめて、実装基板２０と放熱板３５とを締結して電子機器１１となる。
【００４７】
以上説明したように本発明の第２実施の形態に係る電子機器１１によれば、実装基板２０と放熱板３５との締結に、ハトメ１７を用いることにより実装基板２０の組立（固定）に用いたハトメ１４のかしめ用設備が、ハトメ１７のかしめ設備として共用できるので、かしめ用設備費の節減とハトメ１７のかしめ品質の管理が容易となる。その他に、実装基板２０のリフローはんだ付け工程での熱により、先にかしめたハトメ１４のかしめ部に緩みが発生しても、ハトメ１７のかしめにより緩みが修正されるので、余分な工数を必要とせず品質の向上と作業効率が向上しコスト低減が図れる。
【００４８】
尚、本例では実装基板２０と放熱板３５との締結にハトメ１７を用いたが、これに限らずハトメ１７の替わりに、例えば、所定の長さに切断されたアルミや黄銅などの筒を用い、実装基板２０と放熱板３５から突出した両側をかしめて（押し拡げて）実装基板２０と放熱板３５とを締結することもできる。アルミや黄銅の筒を用いればハトメ１４に比べ安価なのでコスト低減が図れる。
【００４９】
次に、第３実施の形態を図４を用いて説明する。図４は本発明の第３実施の形態に係る大型表面実装コネクタを有する電子機器の一部を示す概略図で、（ａ）締結前、（ｂ）締結後の図である。尚、第３実施の形態は第１実施の形態の締結部を除き第１実施の形態と同じであるので、同じ構成については同じ符号を付し変更部分を重点に説明しその他については説明を省略する。
【００５０】
電子機器１２は、実装基板２０、放熱板３５および鋲１８などにより構成されている。
【００５１】
放熱板３５には、実装基板２０のハトメ１４の孔１５と対応する位置に、孔１５と略同じ大きさの鋲挿入孔４０が設けられており、電子機器１２を組み立てるには、実装基板２０のハトメ１４の孔１５と放熱板３５の鋲挿入孔４０とを合わせ、金属製の鋲１８を挿入する。そして、鋲１８の突出部分を押潰して実装基板２０と放熱板３５とを締結して電子機器１２となる。
【００５２】
以上説明したように本発明の第３実施の形態に係る電子機器１２によれば、実装基板２０と放熱板３５との締結に、鋲１８を用いることにより、実装基板２０のリフローはんだ付け工程での熱により、先にかしめたハトメ１４のかしめ部に緩みが発生しても、実装基板２０と放熱板３５との締結時に用いる鋲１８のかしめにより緩みが修正されるので、余分な工数を必要とせず品質の向上と作業効率が向上しコスト低減が図れる。
【００５３】
尚、本例では鋲１８を用いたが鋲１８の替わりに所定の長さの金属棒を用い、実装基板２０と放熱板３５から突出した両側を押潰して実装基板２０と放熱板３５とを固定することもできる。金属棒を用いれば鋲１８に比べ安価なのでコスト低減が図れる。
【００５４】
また、金属製の鋲１８の替わりに樹脂製の鋲を用い、実装基板２０または放熱板３５から突出した部分に熱を加え熱圧着して実装基板２０と放熱板３５とを締結することもできる。その他に、樹脂製の鋲の替わりに所定の長さの樹脂棒を用い、その両側に熱を加え軟化させ熱圧着して実装基板２０と放熱板３５とを締結することもできる。このように金属製の鋲１８を樹脂製の鋲１８に、金属棒を樹脂棒にすることにより重量が軽くなると共に、熱圧着する設備が安価で用意することができるので設備費の節減につながる。
【００５５】
尚、本発明の第１乃至第３の実施の形態では実装基板２０の放熱に放熱板３５を用いたが、これに限らず、例えば、実装基板２０を電子機器の筐体に締結することで筐体を介して放熱することもできる。この場合にも本発明と同じ締結構造を適用することができる。
【００５６】
【発明の効果】
以上説明したように本発明によれば、大型表面実装部品（コネクタ）を有する電子機器の品質向上とコスト低減が図れる大型表面実装部品の固定構造を提供することができる。
【図面の簡単な説明】
【図１】本発明の第１実施の形態に係る実装基板の組立工程を示す概略図である。
【図２】本発明に係る実装基板と放熱板の組立工程を示す概略図である。
【図３】本発明の第２実施の形態に係る大型表面実装コネクタを有する電子機器の一部を示す概略図である。
【図４】本発明の第３実施の形態に係る大型表面実装コネクタを有する電子機器の一部を示す概略図である。
【図５】従来の実装基板の組立工程を示す概略図である。
【図６】従来の実装基板と放熱板の組立工程を示す概略図である。
【符号の説明】
１０，１１，１２・・電子機器
１４，１７・・ハトメ
１５，３２・・孔
１６・・ねじ
１８・・鋲
２０・・実装基板
２１・・基板
２２・・位置決孔
２３，３９・・ハトメ挿入孔
３０・・大型表面実装コネクタ
３１・・位置決ピン
３３・・熱変形部
３５・・放熱板
３６・・ねじ孔
３７，３８・・逃げ孔
４０・・鋲挿入孔[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a structure for fixing a large surface-mounted component mounted on a substrate and a method for fixing a large surface-mounted component.
[0002]
[Prior art]
A conventional structure for fixing a large surface mount component will be described with reference to FIGS.
[0003]
FIG. 5 is a schematic view showing a conventional mounting board assembling process, in which (a) a large-sized surface mount connector is mounted, (b) a screw is tightened (before reflow soldering), (c) is after reflow soldering, and (d). It is a figure after screw re-fastening. FIGS. 6A and 6B are schematic views showing a process of assembling a conventional mounting board and a heat radiating plate, in which FIG.
[0004]
Reference numeral 50 denotes a part of an electronic device having a large-sized surface mount connector 60, which includes a mounting board 55, a heat radiating plate 65, screws 51 and 52, as shown in FIG.
[0005]
As shown in FIG. 5, the mounting board 55 includes a board 56, a large surface mount connector 60, screws 51, and the like.
[0006]
The substrate 56 is an aluminum substrate. The surface of the aluminum plate is electrically insulated by a resin member. A connection circuit for forming an electronic circuit is formed on the surface of the aluminum plate. (Not shown), a pattern for mounting the electrodes of the large surface mount connector 60 (all are not shown), and the like. In addition, a positioning hole 57 of the large surface mount connector 60, a screw hole 58 for attaching the large surface mount connector 60, a hole 59 for attaching to the heat radiating plate 65, and the like are formed.
[0007]
The heat radiating plate 65 is a component that radiates heat of the heat-generating electronic components mounted on the substrate 56 to the outside as shown in FIG. 6, and has a screw hole 66 for mounting the mounting substrate 55, an escape hole 67 for the screw 51, and a positioning pin. 61 are formed with escape holes 68 and the like. As a material of the heat sink 65, a light aluminum member having good heat conductivity is used.
[0008]
First, the assembly of the mounting board 55 will be described with reference to FIG.
[0009]
To assemble the mounting board 55, first, a solder paste is printed (applied) on the pattern portion of the board 56 at the electronic component mounting position. Next, a small electronic component is mounted (mechanically mounted) on the applied solder paste (not shown). In this state, the positioning pins 61 protruding from the mounting surface of the large surface mount connector 60 are inserted into the positioning holes 57 formed on the substrate 56, and the large surface mount connector 60 is placed on the solder paste previously applied. An electrode (not shown) is positioned. Next, the holes 62 provided in the large surface mount connector 60 and the screw holes 59 formed in the substrate 56 are aligned, and the screws 51 are inserted and tightened to fix the large surface mount connector 60 to the substrate 56. In this state, the solder paste is passed through a high-temperature furnace, the solder paste is melted, and the small electronic components and the terminals of the large surface mount connector 60 are soldered (reflow soldering) to the respective pattern portions.
[0010]
Next, assembly of the mounting board and the heat sink will be described with reference to FIG.
[0011]
In order to assemble the mounting board 55 and the heat radiating plate 65 (electronic device 50), the holes 59 formed in the substrate 56 of the mounting board 55 previously assembled and the screw holes 66 formed in the heat radiating plate 65 are aligned with each other. Is inserted and tightened to fix the substrate 56 and the heat sink 65, thereby completing a part of the electronic device 50.
[0012]
Prior art documents relating to the invention of this application include the following.
[0013]
[Patent Document 1]
Japanese Utility Model Publication No. 7-3049 (page 5-7, Fig. 1)
[Patent Document 2]
Japanese Utility Model Publication No. 7-55374 (page 5-7, FIG. 1)
[Patent Document 3]
Japanese Utility Model Publication No. 8-45582
[Problems to be solved by the invention]
However, in the structure of the electronic device 50 described above, when the large surface mount connector 60 is fixed to the substrate 56 by the screw 51, the vibration at the time of screw tightening is applied to the small electronic component previously mounted on the solder paste. Transmission position shift occurs. If reflow soldering is performed in this state, a small electronic component is soldered out of a predetermined position, leading to a problem such as contact with an adjacent electronic component. Further, the resin at the abutment portion of the screw 51 fixing the large-sized surface mount connector 60 is softened and deformed by the heat at the time of reflow soldering, and a thermally deformed portion 63 is formed as shown in FIG. 5C. As a result, since the tightening force of the screw 51 may be insufficient, the screw 51 needs to be re-tightened (re-tightened) after the reflow soldering as shown in FIG.
[0015]
It should be noted that the above-mentioned prior art documents disclosed in Patent Documents 1 and 2 are suitable for fastening relatively large objects, but are not suitable for application to electronic components as in the present invention. However, there is no structure to apply in terms of quality, cost and the like. Further, in the case disclosed in Patent Document 3, when fastening to a heat radiating member abutting on the back surface side of the substrate as in the present invention, mounting holes are provided at predetermined positions, so Only the mounting density of the substrate may be reduced.
[0016]
SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problem, and an object of the present invention is to provide a fixing structure for a large-sized surface-mounted component that can improve the quality of an electronic device having a large-sized surface-mounted component and reduce costs.
[0017]
[Means for Solving the Problems]
The present invention achieves the above-mentioned object, and in a fixing structure of a large surface mounting component for mounting a large surface mounting component on a substrate by reflow soldering, a fixing hole formed in the substrate, A fixing hole formed in the mounting component, a cylindrical fixing component that is inserted through the hole of the substrate and the large-sized surface mounting component, and that expands and fixes a protruding portion from at least one end surface; It is characterized by comprising a substrate and a fastening member inserted into the tubular fixed component fixed to the large surface mount component.
[0018]
Further, the substrate back side member formed on the back side of the substrate is fastened by the fastening member.
[0019]
Further, a screw is used for the fastening member, and a screw hole to be screwed with the screw is formed in the substrate rear surface side member.
[0020]
Further, an eyelet or a tubular member is used as the fastening member, and at least one end or both ends are pushed and expanded for fastening.
[0021]
Also, a rivet or a bar-shaped member is used as the fastening member, and at least one end or both ends are crushed and fastened.
[0022]
Also, a rivet or a rod-shaped member made of resin is used as the fastening member, and at least one end or both ends is thermocompression-bonded and fastened.
[0023]
Further, the substrate back side member is a heat radiating plate.
[0024]
Further, the substrate back side member is a housing.
[0025]
Also, a step of mounting a large surface-mounted component on the substrate to which the solder paste has been applied, a step of fixing the substrate and the large surface-mounted component with a cylindrical fixed component, and a step of mounting the substrate and the large surface-mounted component. And a step of reflow soldering.
[0026]
The method may further include, after the reflow soldering step, a step of inserting a fastening member into a hole of the tubular fixed component and fastening the component.
[0027]
Further, in the fastening step, the substrate, the large-sized surface-mounted component, and a substrate rear surface-side member formed on the rear surface side of the substrate are fastened together.
[0028]
Also, a step of mounting a large surface-mounted component on the substrate to which the solder paste has been applied, a step of fixing the substrate and the large surface-mounted component with a cylindrical fixed component, and a step of mounting the substrate and the large surface-mounted component. And a step of correcting a fixing portion of the tubular fixing component after the reflow soldering step.
[0029]
BEST MODE FOR CARRYING OUT THE INVENTION
An example of an electronic device to which the fixing structure for a large surface-mounted component of the present invention is applied will be described with reference to the drawings.
[0030]
First, a first embodiment will be described with reference to FIGS.
[0031]
FIG. 1 is a schematic view showing an assembling process of a mounting board according to a first embodiment of the present invention, in which (a) a large surface-mounting connector is mounted, (b) eyelets are caulked (fixed), and (c) reflow soldering is performed. It is a figure after (d) eyelet caulking part correction. FIGS. 2A and 2B are schematic views showing a process of assembling the mounting board and the heat sink according to the present invention, wherein FIG.
[0032]
Reference numeral 10 denotes a part of an electronic device having a large-sized surface mount connector 30. As shown in FIG. 2, the electronic device 10 includes a mounting board 20, a heat sink 35, screws 16, and the like.
[0033]
As shown in FIG. 1, the mounting board 20 includes a board 21, large-sized surface mount connectors 30, eyelets 14, and the like.
[0034]
The substrate 21 is an aluminum substrate. As shown in FIG. 1, the surface of the aluminum plate is electrically insulated by a resin member, and a connection circuit for forming an electronic circuit is formed on the surface. Are formed with a pattern for mounting electronic components (not shown), a mounting pattern for electrodes of the large-sized surface mount connector 30 (both not shown), and the like. In addition, a positioning hole 22 and an eyelet insertion hole 23 of the large surface mount connector 30 are formed.
[0035]
The heat radiating plate 35 (corresponding to a fixed object) is a component for releasing the heat of the heat-generating electronic component mounted on the substrate 21 to the outside as shown in FIG. Of the positioning pin 31 and the like. As a material of the heat radiating plate 35, a light aluminum member having good thermal conductivity is used.
[0036]
First, the assembly of the mounting board 20 will be described with reference to FIG.
[0037]
To assemble the mounting board 20, first, a solder paste is printed (applied) on the pattern portion of the board 21 at the electronic component mounting position. Next, a small electronic component is mounted (mechanically mounted) on the applied solder paste (not shown). In this state, the positioning pins 31 protruding from the mounting surface of the large surface-mount connector 30 are inserted into the positioning holes 22 formed in the substrate 21, and the large surface-mount connector 30 is placed on the solder paste previously applied. (Not shown) are positioned. Next, the hole 32 provided in the large surface mount connector 30 and the eyelet insertion hole 23 formed in the substrate 21 are aligned, and the eyelet 14 (for example, a metal such as aluminum or brass cut to a predetermined length) is used. One of the tubes is pushed outward in an umbrella shape). Then, the protruding portion of the eyelet 14 is swaged (expanded) to fix the large-sized surface mount connector 30 to the substrate 21. In this state, the solder paste is passed through a high-temperature furnace, the solder paste is melted, and the small electronic components and the terminals of the large surface mount connector 30 are soldered (reflow soldered) to the respective patterns to form the mounting board 20.
[0038]
Note that the caulking state of the eyelet 14 is temporarily fixed so that the contact surface between the substrate 21 and the large surface mount connector 30 does not separate, so that the vibration generated at the time of caulking is further reduced, and the mounted small-sized This has the effect of further reducing the displacement of electronic components. However, since the fixing force between the board 21 and the large-sized surface mount connector 30 is weakened, there is no member to be fastened using the hole 15 of the eyelet 14 on the back side of the board 21 and the mounting board 20 is used as it is. As shown in FIG. 1 (d), a correction step of re-caulking the caulking portion of the eyelet 14 as necessary may be added.
[0039]
Next, assembly of the mounting board and the heat sink will be described with reference to FIG.
[0040]
In order to assemble the mounting board 20 and the heat radiating plate 35, the holes 15 of the eyelets 14 of the previously assembled mounting board 20 are aligned with the screw holes 36 formed in the heat radiating plate 35, and the screws 16 are inserted into the holes 15 of the eyelets 14. Then, the large-sized surface mount connector 30, the board 21, and the heat sink 35 are fastened in a sandwich shape, whereby a part of the electronic device 10 is completed.
[0041]
As described above, according to the electronic device 10 according to the first embodiment of the present invention, the eyelet 16 is used to fix the large-sized surface-mount connector 30 and the board 21, and when the eyelet 14 is swaged, Since the force applied in the axial direction is mainly generated and the vibration is reduced as compared with the conventional screw fastening, the vibration applied to the electronic component mounted on the solder paste before the reflow soldering can be reduced. Therefore, it is possible to prevent the electronic component from moving from the mounting position of the place due to vibration, and it is possible to solder at a predetermined position, thereby improving quality.
[0042]
Further, since the mounting board 20 and the heat sink 35 are fastened by inserting the screw 16 by utilizing the hole 15 of the eyelet 14, the eyelet 14 fixing the large surface mount connector 30 by heat at the time of reflow soldering. As shown in FIG. 1C, a thermally deformed portion 33 is formed in the resin at the contact portion, and the caulking portion of the eyelet 14 may be loosened. However, in the next assembling step, the looseness is corrected by tightening with the screw 16, so that an extra man-hour is not required, and the quality is improved, the working efficiency is improved, and the cost is reduced.
[0043]
In this embodiment, the eyelets 14 are used for fixing the large surface mount connector 30 of the present invention to the substrate 21. However, the present invention is not limited to this. For example, aluminum or brass cut to a predetermined length may be used instead of the eyelets 14. The large surface mount connector 30 can be fixed to the substrate 21 by caulking (pressing and expanding) both sides of the large surface mount connector 30 and the substrate 21 protruding from the substrate 21. If a cylinder made of aluminum or brass is used, the cost can be reduced because it is cheaper than the eyelet 14.
[0044]
Next, a second embodiment will be described with reference to FIG. FIG. 3 is a schematic view showing a part of an electronic device having a large-sized surface mount connector according to a second embodiment of the present invention, in which (a) is a diagram before fastening and (b) is a diagram after fastening. Since the second embodiment is the same as the first embodiment except for the fastening portion of the first embodiment, the same components are denoted by the same reference numerals, and the description will be focused on the changed portions, and the other portions will be described. Omitted.
[0045]
The electronic device 11 includes a mounting board 20, a heat sink 35, eyelets 17, and the like.
[0046]
The radiator plate 35 is provided with an eyelet insertion hole 39 having substantially the same size as the hole 15 at a position corresponding to the hole 15 of the eyelet 14 of the mounting board 20. The eyelet 14 made of, for example, aluminum or brass is inserted by aligning the hole 15 of the eyelet 14 with the eyelet insertion hole 39 of the heat sink 35. Then, the protruding portion of the eyelet 17 is swaged, and the mounting board 20 and the heat sink 35 are fastened to form the electronic device 11.
[0047]
As described above, according to the electronic device 11 according to the second embodiment of the present invention, the mounting board 20 and the heat sink 35 are fastened to each other by using the eyelets 17 to assemble (fix) the mounting board 20. Since the caulking equipment of the eyelet 14 can be shared as the caulking equipment of the eyelet 17, the cost of the caulking equipment can be reduced and the quality of the caulking of the eyelet 17 can be easily managed. In addition, even if the caulked portion of the eyelet 14 previously caulked is loosened due to the heat in the reflow soldering process of the mounting board 20, the loosening is corrected by caulking the eyelet 17, so extra man-hours are required. It is possible to improve quality and work efficiency and reduce costs.
[0048]
In this example, the eyelets 17 were used for fastening the mounting board 20 and the heat sink 35. However, the present invention is not limited to this, and instead of the eyelets 17, for example, a cylinder of aluminum or brass cut to a predetermined length may be used. The mounting board 20 and the heat radiating plate 35 can be fastened by crimping (pressing and expanding) both sides protruding from the mounting board 20 and the heat radiating plate 35. If a cylinder made of aluminum or brass is used, the cost can be reduced because it is cheaper than the eyelet 14.
[0049]
Next, a third embodiment will be described with reference to FIG. FIG. 4 is a schematic diagram showing a part of an electronic device having a large-sized surface mount connector according to a third embodiment of the present invention, in which (a) is a diagram before fastening and (b) is a diagram after fastening. Since the third embodiment is the same as the first embodiment except for the fastening portion of the first embodiment, the same components are denoted by the same reference numerals, and the changed portions will be mainly described, and the other portions will be described. Omitted.
[0050]
The electronic device 12 includes a mounting board 20, a heat sink 35, studs 18, and the like.
[0051]
The radiator plate 35 is provided with a rivet insertion hole 40 having substantially the same size as the hole 15 at a position corresponding to the hole 15 of the eyelet 14 of the mounting board 20. The holes 15 of the eyelets 14 and the stud insertion holes 40 of the heat sink 35 are aligned, and a metal stud 18 is inserted. Then, the protruding portion of the stud 18 is crushed to fasten the mounting board 20 and the heat radiating plate 35 to form the electronic device 12.
[0052]
As described above, according to the electronic device 12 according to the third embodiment of the present invention, by using the studs 18 to fasten the mounting board 20 and the heat sink 35, the reflow soldering process of the mounting board 20 is performed. If the caulking portion of the eyelet 14 previously caulked is loosened by the heat of the above, the loosening is corrected by caulking the stud 18 used for fastening the mounting board 20 and the heat radiating plate 35. It is possible to improve quality and work efficiency and reduce costs.
[0053]
In this example, the studs 18 were used, but instead of the studs 18, metal rods of a predetermined length were used, and both sides protruding from the mounting board 20 and the heat sink 35 were crushed to connect the mounting board 20 and the heat sink 35. It can also be fixed. If a metal bar is used, the cost can be reduced because it is cheaper than the stud 18.
[0054]
Alternatively, a resin stud may be used instead of the metal stud 18, and heat may be applied to a portion protruding from the mounting board 20 or the heat radiating plate 35 to perform thermocompression bonding to fasten the mounting board 20 and the heat radiating plate 35. . Alternatively, a resin rod having a predetermined length may be used in place of the resin-made stud, and heat may be applied to both sides of the rod to soften and thermocompression-bonded to fasten the mounting substrate 20 and the heat sink 35. In this manner, by using the metal studs 18 as the resin studs 18 and the metal rods as the resin sticks, the weight can be reduced, and the equipment for thermocompression bonding can be prepared at low cost, leading to a reduction in equipment costs. .
[0055]
In the first to third embodiments of the present invention, the heat radiating plate 35 is used for heat radiation of the mounting board 20. However, the present invention is not limited to this. For example, the mounting board 20 may be fastened to the housing of the electronic device. Heat can also be dissipated through the housing. In this case, the same fastening structure as the present invention can be applied.
[0056]
【The invention's effect】
As described above, according to the present invention, it is possible to provide a fixing structure for a large-sized surface-mounted component that can improve the quality and reduce the cost of an electronic device having a large-sized surface-mounted component (connector).
[Brief description of the drawings]
FIG. 1 is a schematic view showing an assembly process of a mounting board according to a first embodiment of the present invention.
FIG. 2 is a schematic view showing a process of assembling a mounting board and a heat sink according to the present invention.
FIG. 3 is a schematic view showing a part of an electronic device having a large-sized surface mount connector according to a second embodiment of the present invention.
FIG. 4 is a schematic view showing a part of an electronic device having a large-sized surface mount connector according to a third embodiment of the present invention.
FIG. 5 is a schematic view showing a process of assembling a conventional mounting board.
FIG. 6 is a schematic view showing a conventional assembly process of a mounting board and a heat sink.
[Explanation of symbols]
10, 11, 12 ··· Electronic equipment 14, 17 ··· Eyelet 15, 32 ··· Hole 16 ··· Screw 18 ··· Tack 20 ··· Mounting board 21 ··· Board 22 ··· Positioning holes 23, 39 ··· Eyelet Insertion hole 30 ・・ Large surface mount connector 31 ・・ Positioning pin 33 ・・ Thermal deformation part 35 ・・ Heat sink 36 ・・ Screw holes 37 and 38 ・・ Escape hole 40 ・・ Tack insertion hole

Claims

In the fixing structure of large surface mount components to mount large surface mount components by reflow soldering on the board,
Fixing holes formed in the substrate,
A fixing hole formed in the large surface mount component,
A cylindrical fixing component that is inserted into the hole of the substrate and the large surface mount component, and that expands and fixes a protruding portion from at least one end surface,
A fixing structure for a large-sized surface-mounted component, comprising: the substrate; and a fastening member inserted into the tubular fixed component fixed to the large-sized surface-mounted component.

The fixing structure for a large-sized surface-mounted component according to claim 1, wherein a member on the back surface of the substrate configured on the back surface side of the substrate is fastened by the fastening member.

5. The large surface mount component according to claim 2, wherein a screw is used as the fastening member, and a screw hole that is screwed to the screw is formed in the substrate back side member. 6. Fixed structure.

The fixing structure for a large-sized surface mount component according to claim 1 or 2, wherein an eyelet or a tubular member is used as the fastening member, and at least one end or both ends are expanded and fastened. .

The fixing structure according to claim 1, wherein a rivet or a bar-shaped member is used as the fastening member, and at least one end or both ends are crushed and fastened.

The large-sized surface mount component according to claim 1, wherein a resin rivet or a rod-shaped member is used as the fastening member, and at least one end or both ends are thermocompressed and fastened. Fixed structure.

The fixing structure for a large surface mount component according to claim 2, wherein the substrate back side member is a heat sink.

The fixing structure for a large-sized surface-mounted component according to claim 2, wherein the substrate back side member is a housing.

A process of mounting a large surface mount component on a substrate coated with solder paste,
Fixing the substrate and the large-sized surface mount component with a cylindrical fixed component,
A step of reflow soldering the substrate and the large-sized surface-mounted component.

The method for fixing a large surface mount component according to claim 9, further comprising: after the reflow soldering step, a step of inserting a fastening member into a hole of the tubular fixing component and fastening the component.

The fixing of the large-sized surface-mounted component according to claim 10, wherein, in the fastening step, the substrate, the large-sized surface-mounted component, and a substrate rear-side member configured on the backside of the substrate are fastened together. Method.

A process of mounting a large surface mount component on a substrate coated with solder paste,
Fixing the substrate and the large-sized surface mount component with a cylindrical fixed component,
A step of reflow soldering the substrate and the large-sized surface mount component,
A method of fixing a large surface mount component, comprising: a step of correcting a fixing portion of the cylindrical fixed component after the reflow soldering step.