JP2005056884A

JP2005056884A - Fixing structure of circuit board

Info

Publication number: JP2005056884A
Application number: JP2003205640A
Authority: JP
Inventors: Tatsuya Matsumoto; 達也松本
Original assignee: TDK Lambda Corp
Current assignee: TDK Lambda Corp
Priority date: 2003-08-04
Filing date: 2003-08-04
Publication date: 2005-03-03
Anticipated expiration: 2023-08-04
Also published as: JP4337137B2

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fixing structure for a circuit board, which is simple in structure and capable of positioning the circuit board easily. <P>SOLUTION: The fixing structure is equipped with a plate-like circuit board 20, a chassis 1 provided with a base 3 and a side 7, and pinching units 9 and 11 which protrude from the side of the chassis 1 toward the side of the circuit board 20 facing the side of the chassis 1 and are provided with U-shaped cutouts 9b and 11c pinching the edge 21 of the circuit board 20 in the direction of height. The side 21b of the circuit board 20 and the side 7b of the chassis 1 are kept separate from each other by a prescribed gap A, and a horizontal distance B between the side 21b of the circuit board 20 and the U-shaped cutouts 9b of the pinching units 9 and 11 is set shorter than the prescribed gap A. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

【０００１】
【発明の属する技術分野】
本発明は、回路基板の固定構造、特に回路基板の縁部をシャーシに形成した挟持部に挿通して基板の位置決めをする回路基板の固定構造に関する。
【０００２】
【従来の技術】
一般に、スイッチング電源などに組み込まれる回路基板には、各種の電子部品が集約的に実装されており、こうした電子部品の中には、例えば、コイルやトランスといった高熱を発する電子部品が含まれている。このような高熱を発する電子部品の熱を放熱させるために、回路基板を取り付けるシャーシには、アルミニウムなどの放熱性に優れた部材が用いられ、放熱性をより一層向上させるために上面や側面が開放されている、いわゆるオープンフレームタイプが採用されている。そして、こうしたシャーシと回路基板との間には、一般に、シャーシや回路基板の仕上り誤差を吸収して作業性を向上させ、また、放熱板であるシャーシからの回路基板への熱伝導を遮断するために、所定の間隔のクリアランスが設定されている。さらに、回路基板はシャーシの底板と平行となるようにして水平に固定され、シャーシには、回路基板を支持する固定片が切り起し形成され、この固定片に回路基板をねじ止めしている。
【０００３】
こうしたねじ止め作業は、回路基板の組付作業工程が増えてしまうので、このようなねじ締め作業を最小限に抑え、しかも、回路基板のシャーシへの取り付け作業を簡易化するため、シャーシの縁部にテーパ状の溝として形成された案内部を設け、この案内部に回路基板の縁部を挿入することにより、回路基板を位置決めする際の作業性の向上を図った回路基板の固定構造が提案されている（例えば、特許文献１参照）。
【０００４】
【特許文献１】
特開平１０−２９００８１号公報
【０００５】
【発明が解決しようとする課題】
しかしながら、上述の特許文献１に開示された回路基板の固定構造においては、回路基板を挿入する方向には、テーパ状の案内部が設けられているため作業性が向上するものの、この案内部には、上述の所定のクリアランスを確保するための深溝が形成されているため、回路基板の位置がずれ易く、基板を固定するための位置だし作業が困難であるという問題が生じていた。
【０００６】
また、シャーシの仕上り精度によっては、この溝部の底と回路基板の側面とが、取り付け状態において接触し、耐振動性能や耐衝撃性能といった特性を損なう虞が生じていた。
【０００７】
そこで、本発明は上記のような従来技術の問題点に鑑みて、簡易な構成で、回路基板の位置決め作業を容易にする回路基板の固定構造を提供することを目的とする。
【０００８】
【課題を解決するための手段】
上記目的を達成するために、本発明に係る回路基板の固定構造は、回路基板をシャーシに取り付けて、該回路基板と該シャーシの底面とを、略平行に位置決めする回路基板の固定構造において、平板状の回路基板と、底面及び側面を有するシャーシと、前記回路基板の縁部を高さ方向に挟持する凹欠部を有し、前記シャーシの前記側面から、該側面と対向している前記回路基板の側面に向かって突出している挟持部とを備え、前記回路基板の前記側面と前記シャーシの前記側面とは、所定の間隔で離隔しており、前記回路基板の前記側面と前記挟持部の前記凹欠部との水平方向の距離は、前記所定の間隔よりも短いことを特徴とする。
【０００９】
このように構成した本発明に係る回路基板の固定構造においては、平板状の回路基板と、底面及び側面を有するシャーシと、回路基板の縁部を高さ方向に挟持する凹欠部を有し、シャーシの側面から、この側面と対向している回路基板の側面に向かって突出している挟持部とを備え、回路基板の側面とシャーシの側面とは、所定の間隔で離隔しており、回路基板の側面と挟持部の凹欠部との水平方向の距離は、この所定の間隔よりも短いので、シャーシ、回路基板の仕上り誤差を吸収し、回路基板の性能を保持するのに必要なシャーシと回路基板との間の所定のクリアランスを維持しつつ、回路基板をシャーシに取り付けた際の挟持部と回路基板とのクリアランスを小さくすることができる。これにより、回路基板をシャーシに取り付ける際の位置だしが容易となり、生産工程での取り付け作業性が向上すると共に、回路基板の耐振動性、耐衝撃性も向上させることができる。
【００１０】
ここで、前記挟持部は、前記シャーシの前記側面から、該側面と対向している前記回路基板の側面に向かって傾斜して形成されている傾斜部を備え、前記回路基板の前記側面に対向している前記凹欠部の底面は、該傾斜部の傾斜方向に対して、略直交する方向に形成されていてもよい。
【００１１】
この場合は、挟持部が、シャーシの側面から、該側面と対向している前記回路基板の側面に向かって傾斜して形成されている傾斜部を備え、回路基板の側面に対向している凹欠部の底面は、この傾斜部の傾斜方向に対して、略直交する方向に形成されているので、回路基板の側面と凹欠部の底面との接触が線接触となる。これにより、回路基板の側面と狭持部との接触が最小限であることが好ましい、例えば多層基板に好適なシャーシの挟持部を提供することができる。
【００１２】
また、前記挟持部は、前記シャーシの前記対向する側面の長手方向端部に設けられ、該挟持部の前記傾斜部の端部は開放されていてもよい。
【００１３】
この場合は、挟持部が、シャーシの対向する側面の長手方向端部に設けられ、この挟持部の傾斜部の端部は開放されているので、回路基板をシャーシの挟持部側から挿通する際に、開放端である傾斜部がガイドの役割を果たし、回路基板の取り付けの作業性を一層向上させることができる。
【００１４】
また、前記挟持部は、前記シャーシの前記対向する側面の長手方向中間部にさらに設けられ、該挟持部の長手方向断面は略台形状であってもよい。
【００１５】
この場合は、挟持部が、シャーシの対向する側面の長手方向中間部にさらに設けられ、この挟持部の長手方向断面は略台形状であるので、開放端挟持部から挿通された回路基板をシャーシ中間部に設けられた略台形状の挟持部により、より一層安定して保持することができる。
【００１６】
【発明の実施の形態】
以下図面を参照して、本発明の好適な一実施形態について説明する。
【００１７】
まず、本発明に係る回路基板の固定構造の概略について、図１を参照して説明する。図１は本発明に係る回路基板の固定構造が適用された回路基板の取り付け状態を模式的に示す斜視図である。
【００１８】
図１に示されるように、本発明の一実施形態に係る回路基板の固定構造においては、底面板３、背面板５及び側面板７の３面から構成されているオープンフレームタイプのシャーシ１に、不図示の電子部品が実装されている回路基板２０が、シャーシ１の底面板３と平行に取り付けられている。ここで、シャーシ１は、底面板３から背面板５と側面板７を垂直に折り曲げることにより構成され、放熱性に優れた、例えばアルミニウムによって成形することができる。また、シャーシ１の側面板７に対向している回路基板２０の縁部２１は、詳細を後述するように、シャーシ１の側面板７の端部に設けられた開放端挟持部９及び略中央部に設けられた台形状挟持部１１により高さ方向に挟持されている。さらに、基板２０の底面は、シャーシ１の底面板３に切り起こし形成された従来構造の不図示の固定片により支持されていると共に、不図示のビス等で固定されている。そして、取り付けの際には、回路基板２０の縁部２１が開放端挟持部９及び台形状挟持部１１を挿通するように、回路基板２０を開放端挟持部９の側から背面板５に向かって挿入することにより、回路基板２０をシャーシ１の低面３と略平行に位置決めすることができる。
【００１９】
なお、本実施形態におけるシャーシ１は、側面板７を片側に有するオープンフレームタイプとしたが、側面板７を両側に有するタイプのシャーシにも適用可能であり、この場合は、上述した開放端挟持部９及び台形状挟持部１１を両側の側面板７に設けることができる。
【００２０】
次に、図２及び図３を参照して、本発明に係るシャーシ１の側面板７の開放側端部に設けられた開放端挟持部９の詳細について説明する。ここで、図２は開放端挟持部を模式的に示す斜視図であり、図３（ａ）は取り付け状態における開放端挟持部近傍の平面図であり、（ｂ）は側面図である。
【００２１】
本発明に係る開放端挟持部９は、図２に示されるように、側面板７の開放端である側縁部７ａから、側面板７に対向している回路基板２０の縁部２１に向かって、長手方向外側に傾斜して突出形成されている傾斜部である一対の挟持片９ａ，９ａと、この挟持片９ａ，９ａの間に形成され、端部が開放されている凹状の切り欠きである凹欠部９ｂとにより構成されている。そして、図３（ａ）に最も良く示されるように、取り付け状態において、側面板７と回路基板２０の縁部２１とは、所定の間隔Ａ（クリアランス）で離隔されている。このクリアランスＡは、組立工程の作業性や、シャーシ１、回路基板２０の仕上り精度を考慮して、適宜所定の値に設定されている。これに対して、回路基板２０の縁部２１が挟持されている挟持片９ａ，９ａの凹欠部９ｂの底部には、底面９ｃが形成されており、この底面９ｃは、挟持片９ａ，９ａの傾斜方向と略直交する方向に形成されている。また、図３（ｂ）に最も良く示されるように、凹欠部９ｂの底面９ｃは、側面板７の基板側側面７ｂよりも、回路基板２０の縁部２１に近く、肉厚に形成されている。すなわち、取り付け状態において、回路基板２０の縁部２１を挟持している挟持部９の凹欠部９ｂに形成されている底面９ｃと回路基板２０の縁部２１の側面２１ｂとの水平方向の距離Ｂは、所定の間隔Ａよりも短くなっている。
【００２２】
以上のように、本実施形態における開放端挟持部９は、回路基板２０の縁部２１が挟持されている挟持片９ａ，９ａの凹欠部９ｂの底部に底面９ｃが形成されており、この底面９ｃと回路基板２０の縁部２１の側面２１ｂとの距離Ｂは、側面板７と回路基板２０の縁部２１との所定の距離Ａよりも短いので、シャーシ１、回路基板２０の仕上り誤差を吸収し、回路基板２０の性能を保持するのに必要なシャーシ１と回路基板２０との間の所定のクリアランスＡを維持しつつ、回路基板２０をシャーシ１に取り付けた際の挟持部９と回路基板２０とのクリアランスＢを小さくすることができる。これにより、回路基板２０をシャーシ１に取り付ける際の位置出しが容易となり、生産工程での取り付け作業性が向上すると共に、回路基板２０の耐振動性、耐衝撃性も向上させることができる。また、挟持部９の挟持片９ａ，９ａが、シャーシ１の側面７から、この側面７と対向している回路基板２０の側面２１ｂに向かって傾斜して形成されており、挟持片９ａ，９ａ間に形成された凹欠部９ｂの底面９ｃは、挟持片９ａ，９ａの傾斜方向に対して、略直交する方向に形成されているので、回路基板２０の側面２１ｂと凹欠部９ｂの底面９ｃとの接触が線接触となる。これにより、回路基板２０の側面２１ｂ若しくはこの近傍に配線等の電気回路が形成されており、側面２１ｂと狭持部９との接触が最小限であることが好ましい基板、例えば多層基板に好適なシャーシ１の挟持部９を提供することができる。さらに、挟持片９ａ，９ａの端部は開放されているので、回路基板２０をシャーシ１の挟持部９側から挿通する際に、開放端である挟持片９ａ，９ａがガイドの役割を果たし、回路基板２０の取り付けの作業性を一層向上させることができる。
【００２３】
次に、図４及び図５を参照して、本発明に係るシャーシ１の側面板７の長手方向中間部に設けられた台形状挟持部１１の詳細について説明する。ここで、図４は台形状挟持部を模式的に示す斜視図であり、図５（ａ）は取り付け状態における台形状挟持部近傍の平面図であり、（ｂ）は側面図である。
【００２４】
本発明に係る台形状挟持部１１は、図４に示されるように、開放端挟持部９の高さに対応して、側面板７の長手方向中間部に設けられ、側面板７に対向している回路基板２０の縁部２１に向かって突出形成されている。そして、この台形状挟持部１１は、長手方向断面が略台形状である一対の挟持片１１ａ，１１ａと、この挟持片１１ａ，１１ａの両端部において、挟持片１１ａ，１１ａを高さ方向に接続し、挟持片１１ａ，１１ａと一体に形成されている基部１１ｂと、これら挟持片１１ａ，１１ａ及び基部１１ｂの間に形成されている凹欠部１１ｃとにより構成されている。ここで、回路基板２０の縁部２１が挟持される凹欠部１１ｃの底部を構成している基部１１ｂには、回路基板２０側に凹欠部１１ｃの底面１１ｄが形成されており、この底面１１ｄは、挟持片１１ａ，１１ａの傾斜方向と略直交する方向に形成されている。そして、図５（ａ），（ｂ）に示されるように、取り付け状態において、前述した開放端挟持部９と同様に、側面板７の基板側側面７ｂと回路基板２０の縁部２１の側面２１ｂとは、所定の間隔Ａ（クリアランス）で離隔されているのに対し、回路基板２０の縁部２１を挟持している台形状挟持部１１の凹欠部１１ｃに形成されている底面１１ｄと回路基板２０の縁部２１の側面２１ｂとの水平方向の距離Ｂは、所定の間隔Ａよりも短くなっている。
【００２５】
以上のように、本実施形態における台形状挟持部１１は、回路基板２０の縁部２１が挟持されている挟持片１１ａ，１１ａの凹欠部１１ｃの底部に底面１１ｄが形成されており、この底面１１ｄと回路基板２０の縁部２１との水平方向の距離Ｂは、側面板７と回路基板２０の縁部２１との所定の距離Ａよりも短いので、シャーシ１、回路基板２０の仕上り誤差を吸収し、回路基板２０の性能を保持するのに必要なシャーシ１と回路基板２０との間の所定のクリアランスＡを維持しつつ、回路基板２０をシャーシ１に取り付けた際の挟持部９と回路基板２０とのクリアランスＢを小さくすることができる。これにより、前述した開放端挟持部９と同様の効果が得られるのに加え、開放端挟持部９と相俟って、シャーシ１の対向する側面７ｂの長手方向中間部にさらに設けられた台形状挟持部１１の凹欠部１１ｃにより、開放端挟持部９から挿通された回路基板２０を、より一層安定して保持することができる。
【００２６】
なお、この台形状挟持部１１は、長手方向中央部に１箇所設けてもよいし、設置間隔が均等になるように、複数箇所設けてもよい。
【００２７】
以上、本発明の回路基板の固定構造について添付図面を参照して説明してきたが、本発明は上記実施形態に限定されるものではなく、本発明の要旨の範囲内で種々の変形実施が可能である。例えば、凹欠部１１ｃの底面１１ｄは、挟持片１１ａ，１１ａの傾斜方向と略直交する方向に形成されていることが好ましいが、回路基板２０の構造や特性によっては、回路基板２０の側面２１ｂと面接触するような平面として形成してもよい。また、回路基板２０の端面とシャーシ１の端面とを揃えるために、シャーシ１の側縁部７ａに切り欠きを設け、この切り欠きから開放端挟持部９を突出させることにより、開放端挟持部９を背面板５側にオフセットさせてもよい。さらに本発明では、シャーシ１の３面を開放した構造で説明したが、シャーシ１の４面を開放した構造にも適用できる。その場合、平板状の回路基板２０に切欠きを設け、この切欠きを利用してシャーシ１に対し回路基板２０をスライドさせることで、同様の位置出しを行なうことが可能になる。また、本発明は、スイッチング電源に限らず各種タイプの電気機器に用いる回路基板の固定構造として広く利用することが可能である。
【００２８】
【発明の効果】
以上説明したとおり、本発明の請求項１に記載の回路基板の固定構造によれば、平板状の回路基板と、底面及び側面を有するシャーシと、回路基板の縁部を高さ方向に挟持する凹欠部を有し、シャーシの側面から、この側面と対向している回路基板の側面に向かって突出している挟持部とを備え、回路基板の側面とシャーシの側面とは、所定の間隔で離隔しており、回路基板の側面と挟持部の凹欠部との水平方向の距離は、この所定の間隔よりも短いので、シャーシ、回路基板の仕上り誤差を吸収し、回路基板の性能を保持するのに必要なシャーシと回路基板との間の所定のクリアランスを維持しつつ、回路基板をシャーシに取り付けた際の挟持部と回路基板とのクリアランスを小さくすることができる。これにより、回路基板をシャーシに取り付ける際の位置だしが容易となり、生産工程での取り付け作業性が向上すると共に、回路基板の耐振動性、耐衝撃性も向上させることができる。
【００２９】
また、請求項２に記載の回路基板の固定構造によれば、前記請求項１において、挟持部が、シャーシの側面から、該側面と対向している前記回路基板の側面に向かって傾斜して形成されている傾斜部を備え、回路基板の側面に対向している凹欠部の底面は、この傾斜部の傾斜方向に対して、略直交する方向に形成されているので、回路基板の側面と凹欠部の底面との接触が線接触となる。これにより、回路基板の側面と狭持部との接触が最小限であることが好ましい、例えば多層基板に好適なシャーシの挟持部を提供することができる。
【００３０】
また、請求項３に記載の回路基板の固定構造によれば、前記請求項２において、挟持部が、シャーシの対向する側面の長手方向端部に設けられ、この挟持部の傾斜部の端部は開放されているので、回路基板をシャーシの挟持部側から挿通する際に、開放端である傾斜部がガイドの役割を果たし、回路基板の取り付けの作業性を一層向上させることができる。
【００３１】
また、請求項４に記載の回路基板の固定構造によれば、前記請求項３において、挟持部が、シャーシの対向する側面の長手方向中間部にさらに設けられ、この挟持部の長手方向断面は略台形状であるので、開放端挟持部から挿通された回路基板をシャーシ中間部に設けられた略台形状の挟持部により、より一層安定して保持することができる。
【図面の簡単な説明】
【図１】本発明に係る回路基板の固定構造が適用された回路基板の取り付け状態を模式的に示す斜視図である。
【図２】開放端挟持部を模式的に示す斜視図である。
【図３】取り付け状態における開放端挟持部近傍を示す図であり、（ａ）は平面図、（ｂ）は側面図である。
【図４】台形状挟持部を模式的に示す斜視図である。
【図５】取り付け状態における台形状挟持部近傍を示す図であり、（ａ）は平面図、（ｂ）は側面図である。
【符号の説明】
１シャーシ
３底面板
５背面板
７側面板
７ａ側縁部
７ｂ基板側側面
９開放端挟持部
９ａ，９ａ挟持片
９ｂ凹欠部
９ｃ底面
１１台形状挟持部
１１ａ，１１ａ挟持片
１１ｂ基部
１１ｃ凹欠部
１１ｄ底面
２０回路基板
２１縁部
２１ｂ側面
Ａクリアランス
Ｂクリアランス[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a circuit board fixing structure, and more particularly to a circuit board fixing structure in which an edge portion of a circuit board is inserted into a holding part formed in a chassis to position the board.
[0002]
[Prior art]
In general, various electronic components are intensively mounted on a circuit board incorporated in a switching power supply or the like, and these electronic components include, for example, electronic components that generate high heat such as coils and transformers. . In order to dissipate the heat of electronic components that generate such high heat, the chassis to which the circuit board is attached uses a member having excellent heat dissipation such as aluminum, and the upper surface and side surfaces are further improved in order to further improve the heat dissipation. A so-called open frame type that is open is employed. In general, between the chassis and the circuit board, a finishing error of the chassis or the circuit board is absorbed to improve workability, and heat conduction from the chassis as a heat sink to the circuit board is cut off. Therefore, a clearance with a predetermined interval is set. Further, the circuit board is horizontally fixed so as to be parallel to the bottom plate of the chassis, and a fixing piece for supporting the circuit board is cut and formed on the chassis, and the circuit board is screwed to the fixing piece. .
[0003]
Such a screwing operation increases the circuit board assembly process. Therefore, in order to minimize such a screw tightening operation and simplify the mounting operation of the circuit board to the chassis, A circuit board fixing structure is provided for improving workability when positioning the circuit board by providing a guide part formed as a tapered groove in the part and inserting the edge of the circuit board into the guide part. It has been proposed (see, for example, Patent Document 1).
[0004]
[Patent Document 1]
Japanese Patent Application Laid-Open No. 10-290081
[Problems to be solved by the invention]
However, in the circuit board fixing structure disclosed in Patent Document 1 described above, since a tapered guide portion is provided in the direction in which the circuit board is inserted, the workability is improved. Since the deep groove for ensuring the above-mentioned predetermined clearance is formed, there is a problem that the position of the circuit board is liable to be shifted and the position finding work for fixing the board is difficult.
[0006]
Further, depending on the finishing accuracy of the chassis, there is a possibility that the bottom of the groove and the side surface of the circuit board come into contact with each other in the mounted state, and characteristics such as vibration resistance performance and impact resistance performance are impaired.
[0007]
In view of the above-described problems of the prior art, an object of the present invention is to provide a circuit board fixing structure that facilitates positioning of a circuit board with a simple configuration.
[0008]
[Means for Solving the Problems]
In order to achieve the above object, a circuit board fixing structure according to the present invention is a circuit board fixing structure in which a circuit board is attached to a chassis, and the circuit board and the bottom surface of the chassis are positioned substantially in parallel. A planar circuit board; a chassis having a bottom surface and a side surface; a recessed portion that sandwiches an edge of the circuit board in a height direction; and facing the side surface from the side surface of the chassis. A clamping part protruding toward the side surface of the circuit board, wherein the side surface of the circuit board and the side surface of the chassis are spaced apart from each other at a predetermined interval, and the side surface of the circuit board and the clamping part The distance in the horizontal direction from the recess is shorter than the predetermined interval.
[0009]
The circuit board fixing structure according to the present invention configured as described above has a flat circuit board, a chassis having a bottom surface and a side surface, and a recessed portion that holds the edge of the circuit board in the height direction. A holding portion that protrudes from the side surface of the chassis toward the side surface of the circuit board facing the side surface, and the side surface of the circuit board and the side surface of the chassis are separated at a predetermined interval, Since the horizontal distance between the side surface of the board and the recessed part of the clamping part is shorter than this predetermined interval, the chassis required to absorb the finishing error of the chassis and the circuit board and maintain the performance of the circuit board. The clearance between the clamping portion and the circuit board when the circuit board is attached to the chassis can be reduced while maintaining a predetermined clearance between the circuit board and the circuit board. This facilitates the positioning when the circuit board is attached to the chassis, improves the workability of attachment in the production process, and improves the vibration resistance and impact resistance of the circuit board.
[0010]
Here, the holding portion includes an inclined portion formed to be inclined from the side surface of the chassis toward the side surface of the circuit board facing the side surface, and opposed to the side surface of the circuit board. The bottom surface of the concave notched portion may be formed in a direction substantially orthogonal to the inclination direction of the inclined portion.
[0011]
In this case, the sandwiching portion includes an inclined portion formed to be inclined from the side surface of the chassis toward the side surface of the circuit board facing the side surface, and the concave portion facing the side surface of the circuit board. Since the bottom surface of the notched portion is formed in a direction substantially orthogonal to the tilt direction of the tilted portion, the contact between the side surface of the circuit board and the bottom surface of the recessed notch portion is a line contact. Thereby, it is preferable that the contact between the side surface of the circuit board and the holding portion is minimal. For example, a holding portion of the chassis suitable for a multilayer board can be provided.
[0012]
Moreover, the said clamping part may be provided in the longitudinal direction edge part of the said opposing side surface of the said chassis, and the edge part of the said inclination part of this clamping part may be open | released.
[0013]
In this case, the clamping part is provided at the longitudinal end of the opposite side surface of the chassis, and the end of the inclined part of the clamping part is open, so that the circuit board is inserted from the chassis clamping part side. In addition, the inclined portion which is an open end serves as a guide, and the workability of mounting the circuit board can be further improved.
[0014]
Moreover, the said clamping part is further provided in the longitudinal direction intermediate part of the said side surface of the said chassis, The longitudinal direction cross section of this clamping part may be substantially trapezoid shape.
[0015]
In this case, the clamping part is further provided in the longitudinal intermediate part of the opposite side surface of the chassis, and the longitudinal section of the clamping part is substantially trapezoidal, so that the circuit board inserted from the open-end clamping part is connected to the chassis. The substantially trapezoidal sandwiching portion provided in the intermediate portion can be held more stably.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a preferred embodiment of the present invention will be described with reference to the drawings.
[0017]
First, an outline of a circuit board fixing structure according to the present invention will be described with reference to FIG. FIG. 1 is a perspective view schematically showing an attached state of a circuit board to which a circuit board fixing structure according to the present invention is applied.
[0018]
As shown in FIG. 1, in the circuit board fixing structure according to an embodiment of the present invention, an open frame type chassis 1 composed of a bottom plate 3, a back plate 5 and a side plate 7 is used. A circuit board 20 on which electronic components (not shown) are mounted is attached in parallel with the bottom plate 3 of the chassis 1. Here, the chassis 1 is configured by vertically bending the back plate 5 and the side plate 7 from the bottom plate 3 and can be formed of, for example, aluminum having excellent heat dissipation. Further, the edge portion 21 of the circuit board 20 facing the side plate 7 of the chassis 1 has an open end clamping portion 9 provided at an end portion of the side plate 7 of the chassis 1 and a substantially central portion as will be described in detail later. It is clamped in the height direction by a trapezoidal clamping unit 11 provided in the section. Further, the bottom surface of the substrate 20 is supported by a fixing piece (not shown) having a conventional structure formed by cutting and raising the bottom plate 3 of the chassis 1 and is fixed by a screw (not shown) or the like. When mounting, the circuit board 20 is directed from the open end holding part 9 side toward the back plate 5 so that the edge 21 of the circuit board 20 passes through the open end holding part 9 and the trapezoidal holding part 11. The circuit board 20 can be positioned substantially parallel to the lower surface 3 of the chassis 1.
[0019]
Although the chassis 1 in this embodiment is an open frame type having the side plate 7 on one side, it can also be applied to a type of chassis having the side plate 7 on both sides. The part 9 and the trapezoidal sandwiching part 11 can be provided on the side plates 7 on both sides.
[0020]
Next, with reference to FIG.2 and FIG.3, the detail of the open end clamping part 9 provided in the open end part of the side plate 7 of the chassis 1 which concerns on this invention is demonstrated. Here, FIG. 2 is a perspective view schematically showing the open end holding portion, FIG. 3A is a plan view of the vicinity of the open end holding portion in the mounted state, and FIG. 2B is a side view.
[0021]
As shown in FIG. 2, the open end clamping portion 9 according to the present invention is directed from the side edge portion 7 a that is the open end of the side plate 7 to the edge portion 21 of the circuit board 20 that faces the side plate 7. A pair of sandwiching pieces 9a, 9a that are inclined and projecting outward in the longitudinal direction, and a concave notch formed between the sandwiching pieces 9a, 9a and having an open end. It is comprised by the recessed part 9b which is. As best shown in FIG. 3A, in the attached state, the side plate 7 and the edge 21 of the circuit board 20 are separated by a predetermined interval A (clearance). The clearance A is appropriately set to a predetermined value in consideration of workability in the assembly process and finishing accuracy of the chassis 1 and the circuit board 20. On the other hand, a bottom surface 9c is formed at the bottom of the recessed portion 9b of the sandwiching piece 9a, 9a on which the edge 21 of the circuit board 20 is sandwiched, and the bottom surface 9c is formed of the sandwiching piece 9a, 9a. It is formed in a direction substantially orthogonal to the inclination direction. Further, as best shown in FIG. 3B, the bottom surface 9c of the recess 9b is closer to the edge 21 of the circuit board 20 than the board side face 7b of the side plate 7, and is formed thick. ing. That is, in the attached state, the horizontal distance between the bottom surface 9 c formed in the recessed portion 9 b of the clamping part 9 that holds the edge 21 of the circuit board 20 and the side surface 21 b of the edge 21 of the circuit board 20. B is shorter than the predetermined interval A.
[0022]
As described above, the open end clamping portion 9 in the present embodiment has the bottom surface 9c formed at the bottom of the recessed portion 9b of the clamping pieces 9a and 9a where the edge 21 of the circuit board 20 is clamped. Since the distance B between the bottom surface 9c and the side surface 21b of the edge 21 of the circuit board 20 is shorter than the predetermined distance A between the side plate 7 and the edge 21 of the circuit board 20, the finishing error of the chassis 1 and the circuit board 20 The holding portion 9 when the circuit board 20 is attached to the chassis 1, while maintaining a predetermined clearance A between the chassis 1 and the circuit board 20 necessary for maintaining the performance of the circuit board 20. The clearance B with the circuit board 20 can be reduced. This facilitates positioning when the circuit board 20 is attached to the chassis 1, improves the workability of attachment in the production process, and improves the vibration resistance and impact resistance of the circuit board 20. Further, the sandwiching pieces 9a, 9a of the sandwiching portion 9 are formed to be inclined from the side surface 7 of the chassis 1 toward the side surface 21b of the circuit board 20 facing the side surface 7, and the sandwiching pieces 9a, 9a The bottom surface 9c of the recess 9b formed therebetween is formed in a direction substantially orthogonal to the inclination direction of the sandwiching pieces 9a, 9a, so that the side surface 21b of the circuit board 20 and the bottom surface of the recess 9b The contact with 9c is a line contact. Thereby, an electric circuit such as wiring is formed on the side surface 21b of the circuit board 20 or in the vicinity thereof, and the contact between the side surface 21b and the holding portion 9 is preferably minimal. The clamping part 9 of the chassis 1 can be provided. Furthermore, since the end portions of the sandwiching pieces 9a, 9a are open, when the circuit board 20 is inserted from the sandwiching portion 9 side of the chassis 1, the sandwiching pieces 9a, 9a which are open ends serve as a guide, The workability of mounting the circuit board 20 can be further improved.
[0023]
Next, with reference to FIG.4 and FIG.5, the detail of the trapezoid holding | grip part 11 provided in the longitudinal direction intermediate part of the side plate 7 of the chassis 1 which concerns on this invention is demonstrated. Here, FIG. 4 is a perspective view schematically showing the trapezoidal sandwiching portion, FIG. 5A is a plan view of the vicinity of the trapezoidal sandwiching portion in the attached state, and FIG. 4B is a side view.
[0024]
As shown in FIG. 4, the trapezoidal sandwiching portion 11 according to the present invention is provided at the middle portion in the longitudinal direction of the side plate 7 corresponding to the height of the open end sandwiching portion 9 and faces the side plate 7. It is formed so as to protrude toward the edge 21 of the circuit board 20. The trapezoidal sandwiching portion 11 connects the sandwiching pieces 11a and 11a in the height direction at a pair of sandwiching pieces 11a and 11a having a substantially trapezoidal cross section in the longitudinal direction and both ends of the sandwiching pieces 11a and 11a. The base 11b is formed integrally with the sandwiching pieces 11a and 11a, and the recess 11c is formed between the sandwiching pieces 11a and 11a and the base 11b. Here, a bottom surface 11d of the recess 11c is formed on the side of the circuit board 20 on the base 11b constituting the bottom of the recess 11c where the edge 21 of the circuit board 20 is sandwiched. 11d is formed in the direction substantially orthogonal to the inclination direction of the clamping pieces 11a and 11a. Then, as shown in FIGS. 5A and 5B, in the mounted state, the side surface 7b of the side plate 7 and the side surface of the edge portion 21 of the circuit board 20 are the same as the open end clamping unit 9 described above. 21b is spaced by a predetermined interval A (clearance), whereas the bottom surface 11d formed in the recessed portion 11c of the trapezoidal sandwiching portion 11 sandwiching the edge 21 of the circuit board 20 The distance B in the horizontal direction from the side surface 21b of the edge 21 of the circuit board 20 is shorter than the predetermined distance A.
[0025]
As described above, the trapezoidal sandwiching portion 11 according to the present embodiment has the bottom surface 11d formed on the bottom of the recessed portion 11c of the sandwiching pieces 11a and 11a on which the edge 21 of the circuit board 20 is sandwiched. Since the horizontal distance B between the bottom surface 11d and the edge 21 of the circuit board 20 is shorter than the predetermined distance A between the side plate 7 and the edge 21 of the circuit board 20, the finishing error of the chassis 1 and the circuit board 20 The holding portion 9 when the circuit board 20 is attached to the chassis 1, while maintaining a predetermined clearance A between the chassis 1 and the circuit board 20 necessary for maintaining the performance of the circuit board 20. The clearance B with the circuit board 20 can be reduced. As a result, the same effect as that of the open end clamping portion 9 described above can be obtained, and in addition to the open end clamping portion 9, a stand further provided at the longitudinal intermediate portion of the opposite side surface 7b of the chassis 1 The circuit board 20 inserted from the open end clamping part 9 can be held more stably by the recess 11c of the shape clamping part 11.
[0026]
In addition, this trapezoidal clamping part 11 may be provided in one place in the center part in the longitudinal direction, or a plurality of places may be provided so that the installation intervals are equal.
[0027]
The circuit board fixing structure of the present invention has been described above with reference to the accompanying drawings. However, the present invention is not limited to the above-described embodiment, and various modifications can be made within the scope of the present invention. It is. For example, the bottom surface 11d of the recessed portion 11c is preferably formed in a direction substantially orthogonal to the inclination direction of the sandwiching pieces 11a and 11a. However, depending on the structure and characteristics of the circuit board 20, the side surface 21b of the circuit board 20 is used. It may be formed as a flat surface that makes surface contact with the surface. Further, in order to align the end face of the circuit board 20 and the end face of the chassis 1, a notch is provided in the side edge portion 7 a of the chassis 1, and the open end holding portion 9 is protruded from the notch, thereby opening the open end holding portion. 9 may be offset to the back plate 5 side. Furthermore, although the present invention has been described with a structure in which the three surfaces of the chassis 1 are opened, the present invention can also be applied to a structure in which the four surfaces of the chassis 1 are opened. In that case, it is possible to perform the same positioning by providing a notch in the flat circuit board 20 and sliding the circuit board 20 with respect to the chassis 1 using this notch. The present invention is not limited to switching power supplies and can be widely used as a circuit board fixing structure used in various types of electrical equipment.
[0028]
【The invention's effect】
As described above, according to the fixing structure of the circuit board according to claim 1 of the present invention, the flat circuit board, the chassis having the bottom surface and the side surface, and the edge of the circuit board are sandwiched in the height direction. And a holding portion that protrudes from the side surface of the chassis toward the side surface of the circuit board facing the side surface, and the side surface of the circuit board and the side surface of the chassis are spaced at a predetermined interval. Since the horizontal distance between the side surface of the circuit board and the notched portion of the clamping part is shorter than the predetermined distance, the finishing error of the chassis and the circuit board is absorbed and the performance of the circuit board is maintained. While maintaining a predetermined clearance required between the chassis and the circuit board, the clearance between the clamping portion and the circuit board when the circuit board is attached to the chassis can be reduced. This facilitates the positioning when the circuit board is attached to the chassis, improves the workability of attachment in the production process, and improves the vibration resistance and impact resistance of the circuit board.
[0029]
According to the circuit board fixing structure of the second aspect, in the first aspect, the clamping portion is inclined from the side surface of the chassis toward the side surface of the circuit board facing the side surface. The bottom surface of the recessed portion that includes the formed inclined portion and faces the side surface of the circuit board is formed in a direction substantially orthogonal to the inclination direction of the inclined portion. And contact with the bottom surface of the recessed portion is line contact. Thereby, it is preferable that the contact between the side surface of the circuit board and the holding portion is minimal. For example, a holding portion of the chassis suitable for a multilayer board can be provided.
[0030]
According to the circuit board fixing structure of the third aspect, in the second aspect, the sandwiching portion is provided at a longitudinal end portion of the opposite side surface of the chassis, and the end portion of the inclined portion of the sandwiching portion is provided. Therefore, when the circuit board is inserted from the holding part side of the chassis, the inclined part which is an open end serves as a guide, and the workability of mounting the circuit board can be further improved.
[0031]
According to the circuit board fixing structure of the fourth aspect of the present invention, in the third aspect of the present invention, the sandwiching portion is further provided in the longitudinal intermediate portion of the opposite side surface of the chassis, and the longitudinal section of the sandwiching portion is Since it is substantially trapezoidal, the circuit board inserted from the open end clamping part can be held more stably by the substantially trapezoidal clamping part provided in the chassis middle part.
[Brief description of the drawings]
FIG. 1 is a perspective view schematically showing an attached state of a circuit board to which a circuit board fixing structure according to the present invention is applied.
FIG. 2 is a perspective view schematically showing an open end clamping portion.
3A and 3B are views showing the vicinity of an open end clamping portion in an attached state, where FIG. 3A is a plan view and FIG. 3B is a side view.
FIG. 4 is a perspective view schematically showing a trapezoidal sandwiching portion.
FIGS. 5A and 5B are diagrams showing the vicinity of a trapezoidal sandwiching portion in an attached state, where FIG. 5A is a plan view and FIG. 5B is a side view;
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Chassis 3 Bottom plate 5 Back plate 7 Side plate 7a Side edge 7b Substrate side side 9 Open end clamping part 9a, 9a Clamping piece 9b Recessed part 9c Bottom surface 11 Trapezoidal clamping part 11a, 11a Clamping part 11b Base part 11c Recessed part Part 11d Bottom 20 Circuit board 21 Edge 21b Side A Clearance B Clearance

Claims

In the circuit board fixing structure in which the circuit board is attached to the chassis and the circuit board and the bottom surface of the chassis are positioned substantially in parallel.
A flat circuit board;
A chassis having a bottom surface and side surfaces;
A holding portion that has a recessed portion that holds the edge portion of the circuit board in a height direction and protrudes from the side surface of the chassis toward the side surface of the circuit board that faces the side surface; ,
The side surface of the circuit board and the side surface of the chassis are separated at a predetermined interval, and a horizontal distance between the side surface of the circuit board and the recessed portion of the clamping portion is the predetermined distance. A circuit board fixing structure characterized by being shorter than the interval.

The sandwiching portion includes an inclined portion that is inclined from the side surface of the chassis toward the side surface of the circuit board facing the side surface, and faces the side surface of the circuit board. 2. The circuit board fixing structure according to claim 1, wherein the bottom surface of the recessed portion is formed in a direction substantially orthogonal to an inclination direction of the inclined portion.

The circuit board according to claim 2, wherein the sandwiching portion is provided at a longitudinal end portion of the opposing side surface of the chassis, and an end portion of the inclined portion of the sandwiching portion is open. Fixed structure.

The fixing of the circuit board according to claim 3, wherein the sandwiching portion is further provided at a longitudinal intermediate portion of the opposite side surface of the chassis, and a longitudinal section of the sandwiching portion is substantially trapezoidal. Construction.