JP4188057B2

JP4188057B2 - Silencer and its manufacturing method

Info

Publication number: JP4188057B2
Application number: JP2002321111A
Authority: JP
Inventors: 善光恒川; 稔郎沢木
Original assignee: Sango Co Ltd
Current assignee: Sango Co Ltd
Priority date: 2002-11-05
Filing date: 2002-11-05
Publication date: 2008-11-26
Anticipated expiration: 2022-11-05
Also published as: JP2004156474A

Description

【０００１】
【発明の属する技術分野】
本発明は消音器とその製造方法に関する。
【０００２】
【従来の技術】
従来、車両に搭載される内燃機関の排気系に使用される消音器の製造方法として、円筒状の外筒の両側における端部と、該外筒の両側を閉塞する端板（エンドプレート）の端部とを、巻締め加工（カーリング形式のシーミング）により接合する方法が一般に知られている。
【０００３】
また、近年、消音器の生産性向上（結合スピードの向上）、気密性確保（排気ガスの洩れ防止）およびカーリング部廃止による材料費低減として、前記の巻締め加工に代わり、レーザ溶接による接合が要求されている。
【０００４】
この要求に応えるため、例えば図８に示すように、消音器を形成する外筒１０１と端板１０２との重ね合わせ面１０３を、消音器本体の軸心と略平行に形成して該外筒１０１と端板１０２とを挿入または巻回し、その重ね合わせ面１０３に対して略直角に貫通レーザ光Ｌを照射して消音器本体の円周方向に沿って全周にわたって接合一体化した消音器が知られている（特許文献１および２参照）。これを第１の従来の技術とする。
【０００５】
また、図９に示すように、テーパ部２０１を形成した封止部材２０２と薄肉状のパイプ２０３とからなり、パイプ２０３の端部に封止部材２０２のテーパ部２０１を圧入嵌合し、パイプ２０３の端部をテーパ部２０１のテーパ形状に沿って変形させて封止部材２０２に密着させ、封止部材２０２の段付面２０４とパイプ２０３の板厚面２０５との突き合わせ部２０６をレーザ光Ｌで溶接するようにしたパイプの溶接方法が知られている（特許文献３参照）。これを第２の従来の技術とする。
【０００６】
更に、図１０に示すように、円筒３０１と蓋３０２の端面に、その板厚方向にテーパ面３０３を形成して、これらのテーパ面３０３を密着させて溶接するレーザ溶接継手構造も知られている（特許文献４参照）。これを第３の従来の技術とする。
【０００７】
【特許文献１】
特許第３１４５３１４号公報（第４頁、図２）
【特許文献２】
特開昭５９−１６２３１８号公報（第２頁、第３図）
【特許文献３】
特許第２６２３６５０号公報（第２頁、第１図）
【特許文献４】
特開昭６２−２３４６８４号公報（第３〜４頁、第２図）
【０００８】
【発明が解決しようとする課題】
ところで、レーザ溶接は、ＭＩＧ溶接やＴＩＧ溶接等の他の溶接に比べて、溶接速度を速くすることができ、また、スパッタが発生しにくい等のメリットがある反面、ＭＩＧ溶接やＴＩＧ溶接では溶接部材同士の隙間が１．２ｍｍ程度でも溶接できるのに対して、レーザ溶接では溶接部材同士の隙間が０．２〜０．３ｍｍ以上であると溶接不良が発生しやすいため、溶接部材同士を隙間なく密着させなければならない問題がある。
【０００９】
したがって、前記第１の従来の技術のように、その外筒１０１と端板１０２とを挿入または巻回してなる構造においては、その重ね合わせ面１０３の隙間を全周にわたって０．２〜０．３ｍｍ以下にすることが困難であるため、レーザ溶接が困難である。また、その溶接を確実に行うためには、その外筒１０１の単品寸法および端板１０２の単品寸法の高精度化や位置決め治具、芯出し治具の高精度化が要求される問題がある。
【００１０】
また、前記第２の従来の技術においては、接合部材相互を密着できるが、封止部材２０２の圧入時に、該封止部材２０２が変形しないように封止部材２０２の板厚をパイプ２０３に比べて厚くし、剛体としなければならないため、この接合方法を外筒と端板が同じ材質、板厚（例えばＳＵＳ４３２Ｔ，０．８ｍｍ）で形成される自動車用消音器の製造に適用することは不適当である。また、段付面２０４とパイプ２０３の突き合わせ溶接であるため、パイプ２０３が、自動車用消音器の外筒のような薄肉であると、そのパイプ２０３側が溶け易いという問題がある。更に、封止部材２０２のテーパ部２０１にパイプ２０３をなつかせて密着させる構造であるため、封止部材２０２のテーパ形状の精度によって密着性が左右され、テーパ形状の高精度化が要求される問題がある。
【００１１】
また、前記第３の従来の技術においては、円筒３０１の板厚方向にテーパ面３０３を形成するため、自動車用消音器のように、薄板の外筒（例えば板厚０．８ｍｍ）の場合には、この接合方法は不適当である。
【００１２】
そこで本発明は、前記の各問題を解決する消音器とその製造方法を提供することを目的とするものである。
【００１３】
【課題を解決するための手段】
前記の課題を解決するために、請求項１記載の第１の発明は、板材を椀状に加工して形成された２個の外筒をレーザ溶接により一体的に接合する消音器において、一方の外筒の開口周縁部に、消音器の軸心に対して直角以外の所定の角度で傾斜し外側に折曲したフランジ部が形成され、他方の外筒の開口周縁部に、消音器の軸心に対して直角以外の所定の角度で傾斜し内側に折曲したフランジ部が形成され、前記両外筒の開口側を相互に対向して前記両フランジを相互に重ね合わせレーザ溶接により貫通溶接したことを特徴とする消音器である。
【００１４】
請求項２記載の第２の発明は、前記第１の発明において、前記２個の外筒のうち、外側に位置するフランジを有する側の外筒において、その軸方向の開口部から内側に入った位置に隔壁が固着されていることを特徴とする消音器である。
【００１８】
請求項３記載の第３の発明は、板材を椀状に加工して形成された２個の外筒をレーザ溶接により一体的に接合する消音器の製造方法において、一方の外筒の開口周縁部に、消音器の軸心に対して直角以外の所定の角度で傾斜し外側に折り曲げられたフランジ部を形成し、他方の外筒の開口周縁部に、消音器の軸心に対して直角以外の所定の角度で傾斜し内側に折り曲げられたフランジ部を形成し、前記両外筒の開口側を相互に対向させて前記両フランジ部を相互に重ね合わせ、前記両外筒を軸心に沿って相互に近接方向に押圧しながら前記重ね合わせ面に対して直交する方向からレーザ光を照射し、両フランジ部をレーザ溶接により貫通溶接したことを特徴とする消音器の製造方法である。
【００２３】
【発明の実施の形態】
本発明の好ましい実施の形態を図１乃至図７に示す実施例に基づいて説明する。
【００２４】
図１は第１実施例を示す。
消音器１の外壁は２個の外筒２，３で構成されており、該外筒２，３は金属製の平板を、例えばパンチとダイスを用いたプレス加工等による深絞り成形によって一方が開口した椀状に形成されており、筒状の一般部２ａ，３ａと底部２ｂ，３ｂを有する。この椀状の成形方法は前記の方法に限るものではない。更に、その径、深さ、断面形状とも任意である。更に、図の例では２個の椀状の外筒２，３を用いたが、これら２個の外筒２，３間に更に筒状の外筒を介在して消音器の外壁を構成してもよい。前記両外筒２，３は金属製の板材からなるため、この構成材を板状部材２ｃ，３ｃとする。
【００２５】
消音器１の一方の外筒２を構成する一方の板状部材２ｃの開口周縁部には，図１（ａ）に示すように、外筒２の軸心（消音器の軸心）Ｘ−Ｘに対して所定の角度θ，例えば略４５°で、外筒２の外側へ折曲したテーパ状の一方のフランジ部４が形成されている。また、他方の外筒３を構成する他方の板状部材３ｃの開口周縁部には，前記一方のフランジ部４の傾斜角θに沿った角度で、外筒３の内側へ折曲したテーパ状の他方のフランジ部５が形成されている。なお、前記一方のフランジ部４を内側へ折曲し、他方のフランジ部５を外側へ折曲してもよい。更に、前記角度θは、４５°に限定されるものではなく、外筒２，３の軸心（消音器の軸心）Ｘ−Ｘに対して直角以外で傾斜していればよい。更に、前記一方のフランジ部４と他方のフランジ部５の角度θは同一角度でなくてもよく、両フランジ部４，５を相互に押し付けた際に、該両フランジ部４，５間に隙間が生じないように略同一角度に設定してもよい。更に、一方のフランジ部４と他方のフランジ部５は、外筒２，３、すなわち、板状部材２ｃ，３ｃの全周にわたって形成されている。
【００２６】
前記両フランジ４，５の成形方法は、例えばパンチによるプレス加工や、スピニング加工等で成形することができ、特に限定するものではない。
【００２７】
図１に示す実施例においては、一方の外筒２内、すなわち、一方の板状部材２ｃ内に隔壁６が嵌合配置されている。該隔壁６は、一方の板状部材２ｃの開口部から若干内側に入った位置に配置され、かつ該隔壁６の外周面が一方の板状部材２ｃの内面にスポット溶接７などにより固着されている。
【００２８】
また、一方の外筒２の底部２ｂと隔壁６間には、小孔８を穿設したインレットパイプ９が貫通架設され、他方の外筒３の底部３ｂと隔壁６間にはアウトレットパイプ１０が貫通架設されている。これら内部構成部品である隔壁６とインレットパイプ９とアウトレットパイプ１０は公知のものであり、これらは図１の構造に限るものではなく、個数、形状、配置レイアウト、接合手段等は任意である。
【００２９】
次に、前記第１実施例における製造方法について説明する。
先ず、隔壁６にインレットパイプ９およびアウトレットパイプ１０を挿通するとともに公知のカシメ接合１１により一体的に組み付けてサブアッセンブリとする。
【００３０】
次に、前記サブアッセンブリを一方の外筒２の開口側から挿入するとともにインレットパイプ９の先端側を一方の外筒２の底部２ｂに貫入し、隔壁６と一方の外筒２における一般部２ａの板状部材２ｃとをスポット溶接７で固着する。
【００３１】
次に、他方の外筒３の開口側を前記一方の外筒２の開口側に対向させて、両外筒２と３の一方のフランジ部４と他方のフランジ部５同士が重なりあうように配置するとともに、アウトレットパイプ１０の後端側を他方の外筒３の底部３ｂに貫入する。
【００３２】
次に、両外筒２と３を、該外筒２，３の軸心、すなわち消音器の軸心Ｘ−Ｘに沿って相互に近接する方向Ａへ適宜加圧手段（図示せず）により押圧して両フランジ部４，５を圧着しながら、両フランジ部４，５の重ね合わせ面１２に対して略直角にレーザ光Ｌを外筒２の外部から照射し、より詳しくは、フランジ４の表面に照射し、例えばレーザ光Ｌを発する溶接トーチ側を軸心Ｘ−Ｘを中心として回転させ、外筒２，３の周方向、すなわち板状部材２ｃ，３ｃの円周方向に沿って全周または部分的に貫通溶接し、両フランジ部４，５を一体化させる。
【００３３】
なお、前記の貫通溶接は、図１（ｃ）に示すように、レーザビームを２枚のフランジ部４，５に貫通させる溶接Ｗ１と、図１（ｄ）に示すように、レーザビームを１枚のフランジ部４だけ貫通させ、残りのフランジ部５は板厚方向の途中までとする溶接Ｗ２も含むものである。
【００３４】
前記の貫通溶接時には、両フランジ部４，５が相向き合うテーパ状であること、および両フランジ部４，５を近接方向に押圧しながらレーザ溶接することにより、両フランジ部４，５同士の単品形状の角度、フランジ面精度がバラついていたとしても、両フランジ部４，５同士が変形し、互いになつき合って密着し、その重ね合わせ面１２の隙間を全周にわたってなくすことができ、安定したレーザ溶接が可能になる。
【００３５】
また、溶接進行途中において発生する動的な隙間に対しても、両フランジ部４，５同士を近接方向に押圧しながらレーザ溶接することにより、両フランジ部４，５同士が互いになつき合って密着し、同様に安定したレーザ溶接が可能になる。
なお、前記動的な隙間とは、フランジ部全体（全周）への溶接による入熱量は、溶接の進行とともに増加するため、フランジ部の熱歪量は全周にわたって一定ではなく、溶接の進行途中（開始から終了までの間）において進行方向で隙間の大きさが変動することをいう。
【００３６】
また、外側に位置するフランジ部４を有する側の外筒２に隔壁６を固設したので、この隔壁６の存在により外筒２の一般部２ａ、すなわち板状部材２ｃの一般部の剛性が高くなり、押圧時における板状部材２ｃの一般部の変形（口開き）が防止され、両フランジ部４，５のみが変形し、互いになつき合って密着する。したがって、消音器のように外筒、すなわち板状部材４，５の板圧が０．数ｍｍと薄い場合には有効である。
【００３７】
また、図１に示す実施例のように、椀状に形成された外筒を２個設けて、これらの開口部にフランジ部４，５を形成し、該フランジ部４，５を相互に接合して消音器１を構成するようにしたものにおいては、消音器１全体としての外壁の接合箇所が１箇所となり、レーザ溶接工程が少なくてすむ効果がある。
【００３８】
図２は第２実施例を示す。
本第２実施例は、前記実施例における内側に位置する他方のフランジ部５を変形させたものである。
【００３９】
すなわち、前記他方のフランジ部５を径方向の外側へ山状に屈曲させたリブ状フランジ部５Ａとし、両外筒２，３の一般部２ａ，３ａの外径Ｒを同径にしたものである。その他の構造および製造方法は前記第１実施例と同様である。なお、このリブ状フランジ部５Ａを谷状に形成し、フランジ部４を内側へ折曲してもよい。
【００４０】
本第２実施例においては、フランジ部４，５Ａの成形前段階における一方の外筒２と他方の外筒３の外径Ｒを同径にすることができ、深絞りのパンチとダイスを１種類だけ用意すればよい特長がある。
【００４１】
前記第１実施例のように、一方の外筒２と他方の外筒３の外径が異なるものにおいては、パンチとダイスを２種類用意する必要があり、型費が嵩むのに対し、本第２実施例では型費が低減され、かつ、フランジ部４，５Ａの成形前段階における一方の外筒２と他方の外筒３の共通化を図ることができる。
【００４２】
なお、本第２実施例のように、リブ状フランジとした場合においても、前記第１実施例と同様に、一方の外筒２における一般部２ａの外径Ｒと他方の外筒３における一般部３ａの外径Ｒを異ならしめてもよい。
【００４３】
図３は第３実施例を示す。
本第３実施例は、前記第２実施例（図２）のリブ状フランジ５Ａの先端部に、外筒２の軸心Ｘ−Ｘと平行に延長する延長片５ａを形成したリブ状フランジ５Ｂとしたものである。
【００４４】
その他の構造および製造方法は前記第２実施例と同様である。
本第３実施例においても前記第２実施例と同様の効果を発揮できる。
【００４５】
なお、本第３実施例のように、リブ状フランジ５Ｂとした場合においても、前記第１実施例と同様に、一方の外筒２における一般部２ａの外径Ｒと他方の外筒３における一般部３ａの外径Ｒを異ならしめてもよい。
【００４６】
図４は第４実施例を示す。
本第４実施例は、前記第２実施例（図２）のリブ状フランジ部５Ａを外側へコの字状に形成したリブ状フランジ部５Ｃとしたものである。また、一方のフランジ部４の先部４ａは、前記リブ状フランジ部５Ｃの外面まで延長されている。
【００４７】
その他の構造および製造方法は前記第２実施例と同様である。
本第４実施例においても前記第２実施例と同様の効果を発揮できる。
【００４８】
なお、本第３実施例のように、リブ状フランジ５Ｃとした場合においても、前記第１実施例と同様に、一方の外筒２における一般部２ａの外径Ｒと他方の外筒３における一般部３ａの外径Ｒを異ならしめてもよい。
【００６１】
図５はレーザ溶接の他の方法を示すもので、前記のように、例えば第１実施例の両フランジ部４，５を圧接した状態において、他方の外筒３に形成したアウトレットパイプ１０の挿通穴１５を通じてレーザ光Ｌをフランジ部５の内部側から照射するようにしたものである。このレーザ光Ｌの照射時にインレットパイプ９やアウトレットパイプ１０が存在するとこれらがレーザ光Ｌの照射の妨げとなるため、インレットパイプ９とアウトレットパイプ１０は、レーザ光Ｌによる溶接後に組み付ける。すなわち、隔壁６を予め一方の外筒２内に前記のように配置固着しておき、レーザ光照射後に、インレットパイプ９およびアウトレットパイプ１０を挿入し、この両パイプ９，１０の内側から両パイプ９，１０を隔壁６にカシメて、カシメ接合１１により固定する。
【００６２】
この実施例によれば、レーザ貫通溶接による裏ビードを消音器１の外部から目視で確認できる。
【００６３】
このような図５に示す溶接方法を、前記各実施例について適用してもよい。
以上の実施例の他に、次のような実施例でもよい。
【００６４】
前記図２および図３に示すリブ状のフランジ部５Ａ，５Ｂの径寸法を、一方のフランジ部４の径寸法よりも若干大きく設定し、一方のフランジ部４をリブ状フランジ部５Ａ，５Ｂで拡径させながら両フランジ部を密着させる、圧入式としてもよい。
【００６５】
また、図１〜図４に示すフランジ部において、両フランジ部を接触させた後に、一方のフランジ部４の外側から他方のフランジ部５，５Ａ〜５Ｄに向けて、スピニング加工やスウェージング加工等により縮径加工を施して両フランジ部を絞り、両フランジ部をなつかせるようにしてもよい。
【００６６】
更に、前記各実施例におけるレーザ光Ｌを発する溶接トーチを図６に示すように、消音器１の円周方向において２個、略１８０°で対向する位置に配置し、該２個の溶接トーチ２１，２２を、円周方向に沿って同方向へ同時に半周ずつ走らせて、溶接ａと溶接ｂを同時に半周ずつ行うようにしてもよい。
【００６７】
これにより、１個の溶接トーチで全周溶接する場合に比べて、溶接時間が半分に短縮される。また、入熱バランスがよく、溶接熱によるワーク歪（熱変形）を抑えることができ、両フランジ相互の密着性が高まる。
【００６８】
なお、この溶接トーチの個数は等間隔に３個以上設けてもよい。
図７は前記図１乃至図４に示す実施例におけるレーザ貫通溶接の検査方法の実施例を示す。
【００６９】
前記図１乃至図４に示す実施例では、レーザ貫通溶接によって生じる裏波（裏ビード）が消音器１の内部に形成されるため、消音器１の外部からは裏波を目視で確認しずらく、また、過流深傷等の方法も取れない。
【００７０】
そこで、図７に示すように、例えばインレットパイプ９を通じて光センサ３１を消音器１内に挿入配置し、フランジ部４，５において、レーザ光によるレーザ溶接Ｗが貫通したときに、その裏波側から出るアークを前記の光センサ３１などで検知して、貫通溶接を確認するようにしたものである。なお、前記光センサ３１の代わりに、熱センサを用いて、貫通溶接時に消音器１内に生じる熱によって確認するようにしてもよい。
【００７１】
【発明の効果】
以上のようであるから、請求項１記載の発明によれば、両フランジ部を、消音器の軸心に対して直角以外の所定の角度で傾斜させたので、重ね合わせた両フランジ部を消音器の軸心方向に沿って近接方向に押圧しながらレーザ溶接することにより、フランジ部同士の単品状態での角度やフランジ面精度がバラついていても、両フランジ部同士が変形し、互いになつき合って密着し、重ね合わせ面の隙間を全周にわたってなくし、安定したレーザ溶接が可能になる。
【００７２】
更に、消音器の外壁が、２個の椀状物を、各開口側で嵌合して構成されるため、その１個の嵌合部における両フランジ部を溶接するのみでよく、溶接箇所が１箇所となり、レーザ溶接工程が少なくてすむ効果がある。
【００７６】
請求項３の発明によれば、前記の効果を発揮する消音器の製造方法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実施例を示すもので、（ａ）は消音器全体の断面図、（ｂ）は（ａ）における丸部Ｂの拡大断面図、（ｃ）（ｄ）は貫通溶接を示す断面図。
【図２】本発明の第２実施例を示す接合部の拡大断面図。
【図３】本発明の第３実施例を示す接合部の拡大断面図。
【図４】本発明の第４実施例を示す接合部の拡大断面図。
【図５】本発明におけるレーザ光の照射方法の実施例を示す断面図。
【図６】本発明における溶接方法の実施例を説明する図。
【図７】本発明における溶接検査方法の実施例を説明する図。
【図８】第１の従来の構造を示す断面図。
【図９】第２の従来の構造を示す断面図。
【図１０】第３の従来の構造を示す断面図。
【符号の説明】
１消音器
２，３外筒
２ｃ，３ｃ板状部材
４フランジ部
５，５Ａ〜５Ｅフランジ部
Ｌレーザ光
Ｘ−Ｘ消音器の軸心[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a silencer and a manufacturing method thereof.
[0002]
[Prior art]
Conventionally, as a method of manufacturing a silencer used in an exhaust system of an internal combustion engine mounted on a vehicle, end portions on both sides of a cylindrical outer cylinder, and end plates (end plates) closing both sides of the outer cylinder are used. A method is generally known in which the end portions are joined by winding (curling type seaming).
[0003]
Also, in recent years, instead of the above-mentioned winding process, joining by laser welding has been used as a means of improving silencer productivity (improving coupling speed), ensuring airtightness (preventing exhaust gas leakage) and reducing material costs by eliminating the curling part. It is requested.
[0004]
In order to meet this requirement, for example, as shown in FIG. 8 , an overlapping surface 103 of the outer cylinder 101 and the end plate 102 forming the silencer is formed substantially parallel to the shaft center of the silencer main body to form the outer cylinder. A silencer in which 101 and an end plate 102 are inserted or wound, and the penetrating laser beam L is irradiated at a substantially right angle to the overlapping surface 103 so as to be joined and integrated along the circumferential direction of the silencer body. Is known (see Patent Documents 1 and 2). This is the first conventional technique.
[0005]
Further, as shown in FIG. 9 , the sealing member 202 is formed with a tapered portion 201 and a thin pipe 203, and the tapered portion 201 of the sealing member 202 is press-fitted into the end portion of the pipe 203. The end portion of 203 is deformed along the taper shape of the taper portion 201 and brought into close contact with the sealing member 202, and the butted portion 206 between the stepped surface 204 of the sealing member 202 and the plate thickness surface 205 of the pipe 203 is laser light. A pipe welding method in which welding is performed with L is known (see Patent Document 3). This is the second conventional technique.
[0006]
Furthermore, as shown in FIG. 10, there is also known a laser welded joint structure in which a tapered surface 303 is formed on the end surfaces of a cylinder 301 and a lid 302 in the plate thickness direction, and these tapered surfaces 303 are in close contact and welded. (See Patent Document 4). This is the third conventional technique.
[0007]
[Patent Document 1]
Japanese Patent No. 3145314 (page 4, FIG. 2)
[Patent Document 2]
JP 59-162318 (2nd page, FIG. 3)
[Patent Document 3]
Japanese Patent No. 2623650 (second page, FIG. 1)
[Patent Document 4]
JP 62-234684 A (pages 3 to 4, FIG. 2)
[0008]
[Problems to be solved by the invention]
By the way, laser welding has advantages such as higher welding speed and less spatter generation compared to other welding such as MIG welding and TIG welding, but welding in MIG welding and TIG welding. While welding is possible even when the gap between members is about 1.2 mm, laser welding tends to cause poor welding if the gap between weld members is 0.2 to 0.3 mm or more. There is a problem that must be closely adhered.
[0009]
Therefore, in the structure in which the outer cylinder 101 and the end plate 102 are inserted or wound as in the first prior art, the clearance of the overlapping surface 103 is 0.2 to 0. Since it is difficult to make it 3 mm or less, laser welding is difficult. In addition, in order to perform the welding reliably, there is a problem that it is required to improve the accuracy of the single product size of the outer cylinder 101 and the single product size of the end plate 102 and the accuracy of the positioning jig and the centering jig. .
[0010]
In the second prior art, the joining members can be brought into close contact with each other, but the thickness of the sealing member 202 is compared with that of the pipe 203 so that the sealing member 202 is not deformed when the sealing member 202 is press-fitted. Therefore, this joining method cannot be applied to the manufacture of a silencer for automobiles in which the outer cylinder and the end plate are made of the same material and plate thickness (for example, SUS432T, 0.8 mm). Is appropriate. In addition, since the stepped surface 204 and the pipe 203 are butt-welded, if the pipe 203 is thin like the outer cylinder of an automobile silencer, there is a problem that the pipe 203 side is easily melted. Further, since the pipe 203 is connected to the tapered portion 201 of the sealing member 202 in close contact, the adhesiveness depends on the accuracy of the tapered shape of the sealing member 202, and high accuracy of the tapered shape is required. There's a problem.
[0011]
In the third prior art, since the tapered surface 303 is formed in the thickness direction of the cylinder 301, the outer cylinder is a thin plate (for example, a thickness of 0.8 mm) as in a car silencer. However, this joining method is inappropriate.
[0012]
Accordingly, an object of the present invention is to provide a silencer that solves each of the above problems and a method for manufacturing the silencer.
[0013]
[Means for Solving the Problems]
In order to solve the above-mentioned problem, a first invention according to claim 1 is a silencer in which two outer cylinders formed by processing a plate material into a bowl shape are integrally joined by laser welding. A flange portion that is inclined at a predetermined angle other than a right angle with respect to the shaft center of the silencer and is bent outward is formed on the outer periphery of the outer cylinder of the outer cylinder. A flange portion that is inclined at a predetermined angle other than a right angle with respect to the shaft center and bent inward is formed, the opening sides of the outer cylinders are opposed to each other, and the flanges are overlapped with each other and penetrated by laser welding. It is a silencer characterized by welding.
[0014]
According to a second aspect of the present invention, in the first aspect, of the two outer cylinders, the outer cylinder on the side having a flange positioned on the outside enters the inside from the axial opening. The silencer is characterized in that a partition wall is fixed at a certain position.
[0018]
A third invention of claim 3, wherein, in the method for manufacturing a muffler integrally joining two of the outer cylinder formed by processing a plate material like a bowl by laser welding, the opening peripheral edge of one of the outer cylinder A flange portion that is inclined at a predetermined angle other than a right angle with respect to the shaft center of the silencer and bent outward is formed at the portion, and a right angle with respect to the shaft center of the silencer is formed at the opening peripheral edge of the other outer cylinder. Forming a flange portion that is inclined at a predetermined angle and bent inward, the opening sides of the two outer cylinders are opposed to each other, the two flange portions are overlapped with each other, and the two outer cylinders are axially centered. A method of manufacturing a silencer, characterized in that a laser beam is irradiated from a direction orthogonal to the overlapping surface while being pressed in the proximity direction to each other, and both flange portions are through-welded by laser welding.
[0023]
DETAILED DESCRIPTION OF THE INVENTION
The preferred embodiments of the present invention will be described with reference to the embodiments shown in FIGS. 1-7.
[0024]
FIG. 1 shows a first embodiment.
The outer wall of the silencer 1 is composed of two outer cylinders 2 and 3, and the outer cylinders 2 and 3 are made of a metal flat plate by deep drawing, for example, by press working using a punch and a die. It is formed in an open bowl shape and has cylindrical general portions 2a and 3a and bottom portions 2b and 3b. This bowl-shaped forming method is not limited to the above method. Furthermore, the diameter, depth, and cross-sectional shape are arbitrary. Furthermore, in the example shown in the figure, two bowl-shaped outer cylinders 2 and 3 are used. However, an outer wall of the silencer is configured by further interposing a cylindrical outer cylinder between the two outer cylinders 2 and 3. May be. Since both the outer cylinders 2 and 3 are made of a metal plate, the constituent members are referred to as plate-like members 2c and 3c.
[0025]
As shown in FIG. 1 (a), the axial center of the outer cylinder 2 (axial center of the silencer) X- is provided at the opening peripheral edge of one plate-like member 2c constituting one outer cylinder 2 of the silencer 1. One tapered flange portion 4 that is bent outward from the outer cylinder 2 is formed at a predetermined angle θ with respect to X, for example, approximately 45 °. Further, the opening peripheral edge of the other plate-like member 3c constituting the other outer cylinder 3 is tapered so as to be bent inward of the outer cylinder 3 at an angle along the inclination angle θ of the one flange portion 4. The other flange portion 5 is formed. The one flange portion 4 may be bent inward, and the other flange portion 5 may be bent outward. Further, the angle θ is not limited to 45 °, and may be inclined at a position other than a right angle with respect to the axial center (axial center of the silencer) XX of the outer cylinders 2 and 3. Further, the angle θ between the one flange portion 4 and the other flange portion 5 may not be the same angle, and when the flange portions 4 and 5 are pressed against each other, there is a gap between the flange portions 4 and 5. May be set at substantially the same angle so as not to occur. Furthermore, the one flange portion 4 and the other flange portion 5 are formed over the entire circumferences of the outer cylinders 2 and 3, that is, the plate-like members 2c and 3c.
[0026]
The method for forming the flanges 4 and 5 can be formed by, for example, punching or spinning, and is not particularly limited.
[0027]
In the embodiment shown in FIG. 1, a partition wall 6 is fitted and arranged in one outer cylinder 2, that is, one plate-like member 2c. The partition wall 6 is disposed at a position slightly inside the opening of one plate-like member 2c, and the outer peripheral surface of the partition wall 6 is fixed to the inner surface of the one plate-like member 2c by spot welding 7 or the like. Yes.
[0028]
Further, an inlet pipe 9 having a small hole 8 is provided between the bottom 2b of one outer cylinder 2 and the partition wall 6, and an outlet pipe 10 is provided between the bottom 3b of the other outer cylinder 3 and the partition wall 6. It is built through. The partition 6, the inlet pipe 9, and the outlet pipe 10 which are these internal components are well known, and these are not limited to the structure shown in FIG. 1, and the number, shape, layout, joining means, etc. are arbitrary.
[0029]
Next, the manufacturing method in the first embodiment will be described.
First, the inlet pipe 9 and the outlet pipe 10 are inserted into the partition wall 6 and are integrally assembled by a known caulking joint 11 to form a subassembly.
[0030]
Next, the subassembly is inserted from the opening side of one outer cylinder 2 and the distal end side of the inlet pipe 9 is inserted into the bottom 2b of the one outer cylinder 2, so that the partition wall 6 and the general portion 2a in the one outer cylinder 2 are inserted. The plate-like member 2 c is fixed by spot welding 7.
[0031]
Next, the opening side of the other outer cylinder 3 is opposed to the opening side of the one outer cylinder 2 so that one flange portion 4 and the other flange portion 5 of the outer cylinders 2 and 3 overlap each other. While arrange | positioning, the rear-end side of the outlet pipe 10 penetrates into the bottom part 3b of the other outer cylinder 3. FIG.
[0032]
Next, both outer cylinders 2 and 3 are appropriately pressed by a pressing means (not shown) in the direction A adjacent to each other along the axis of the outer cylinders 2 and 3, that is, the axis XX of the silencer. While pressing the two flange portions 4 and 5, the laser beam L is irradiated from the outside of the outer cylinder 2 at a substantially right angle with respect to the overlapping surface 12 of the both flange portions 4 and 5. For example, the welding torch side that emits the laser beam L is rotated about the axis XX, and along the circumferential direction of the outer cylinders 2 and 3, that is, the circumferential direction of the plate-like members 2c and 3c. The flanges 4 and 5 are integrated by through-welding the entire circumference or partially.
[0033]
In addition, as shown in FIG. 1 (c), the above-mentioned through welding includes welding W1 that penetrates the laser beam through the two flange portions 4 and 5, and laser beam 1 as shown in FIG. 1 (d). Only the flange portion 4 of the sheet is penetrated, and the remaining flange portion 5 also includes a weld W2 that is halfway in the plate thickness direction.
[0034]
At the time of the above-mentioned through welding, both flange portions 4 and 5 are tapered so that they face each other, and laser welding is performed while pressing both flange portions 4 and 5 in the proximity direction, so that both flange portions 4 and 5 are separated from each other. Even if the angle of the shape and the accuracy of the flange surface are varied, the flange portions 4 and 5 are deformed, and are in close contact with each other, so that the gap between the overlapping surfaces 12 can be eliminated over the entire circumference and stable. Laser welding is possible.
[0035]
In addition, both flange portions 4 and 5 are brought into close contact with each other by laser welding while pressing both flange portions 4 and 5 in the proximity direction even with respect to dynamic gaps that occur during welding progress. Similarly, stable laser welding is possible.
The dynamic gap means that the amount of heat input by welding to the entire flange portion (entire circumference) increases with the progress of welding, so the amount of thermal strain of the flange portion is not constant over the entire circumference, and the progress of welding. It means that the size of the gap fluctuates in the traveling direction in the middle (from the start to the end).
[0036]
Further, since the partition wall 6 is fixed to the outer cylinder 2 on the side having the flange portion 4 located on the outside, the presence of the partition wall 6 increases the rigidity of the general portion 2a of the outer cylinder 2, that is, the general portion of the plate-like member 2c. The height is increased, the deformation (opening) of the general part of the plate-like member 2c at the time of pressing is prevented, and only the two flange parts 4 and 5 are deformed, and are brought into close contact with each other. Therefore, the outer cylinder, that is, the plate pressure of the plate-like members 4 and 5 is 0. It is effective when it is as thin as several mm.
[0037]
Further, as in the embodiment shown in FIG. 1, two outer cylinders formed in a bowl shape are provided, and flange portions 4 and 5 are formed in these openings, and the flange portions 4 and 5 are joined to each other. Thus, the silencer 1 constituting the silencer 1 has an effect of reducing the number of laser welding processes since there is only one joint portion of the outer wall of the silencer 1 as a whole.
[0038]
FIG. 2 shows a second embodiment.
In the second embodiment, the other flange portion 5 located on the inner side in the embodiment is deformed.
[0039]
That is, the other flange portion 5 is a rib-like flange portion 5A bent in a mountain shape outward in the radial direction, and the outer diameters R of the general portions 2a and 3a of both the outer cylinders 2 and 3 are the same. is there. Other structures and manufacturing methods are the same as those in the first embodiment. The rib-shaped flange portion 5A may be formed in a valley shape, and the flange portion 4 may be bent inward.
[0040]
In the second embodiment, the outer diameter R of one outer cylinder 2 and the other outer cylinder 3 in the pre-molding stage of the flange portions 4 and 5A can be made the same diameter, and the deep drawing punch and the die are 1 There is a feature that only needs to be prepared.
[0041]
In the case where the outer diameters of one outer cylinder 2 and the other outer cylinder 3 are different as in the first embodiment, it is necessary to prepare two types of punches and dies, which increases the mold cost. In the second embodiment, the mold cost is reduced, and the one outer cylinder 2 and the other outer cylinder 3 can be made common in the stage before molding the flange portions 4 and 5A.
[0042]
Even in the case of the rib-like flange as in the second embodiment, the outer diameter R of the general portion 2a in one outer cylinder 2 and the general in the other outer cylinder 3 are the same as in the first embodiment. The outer diameter R of the portion 3a may be made different.
[0043]
FIG. 3 shows a third embodiment.
In the third embodiment, a rib-like flange 5B in which an extension piece 5a extending in parallel with the axis XX of the outer cylinder 2 is formed at the tip of the rib-like flange 5A of the second embodiment (FIG. 2). It is what.
[0044]
Other structures and manufacturing methods are the same as those in the second embodiment.
In the third embodiment, the same effects as in the second embodiment can be exhibited.
[0045]
Even when the rib-like flange 5B is used as in the third embodiment, the outer diameter R of the general portion 2a in one outer cylinder 2 and the other outer cylinder 3 are the same as in the first embodiment. The outer diameter R of the general part 3a may be made different.
[0046]
FIG. 4 shows a fourth embodiment.
In the fourth embodiment, the rib-like flange portion 5A of the second embodiment (FIG. 2) is formed as a rib-like flange portion 5C formed outwardly in a U-shape. Moreover, the front part 4a of one flange part 4 is extended to the outer surface of the said rib-shaped flange part 5C.
[0047]
Other structures and manufacturing methods are the same as those in the second embodiment.
In the fourth embodiment, the same effects as in the second embodiment can be exhibited.
[0048]
Even in the case of the rib-like flange 5C as in the third embodiment, the outer diameter R of the general portion 2a in one outer cylinder 2 and the other outer cylinder 3 are the same as in the first embodiment. The outer diameter R of the general part 3a may be made different.
[0061]
FIG. 5 shows another method of laser welding. As described above, for example, in the state in which the flange portions 4 and 5 of the first embodiment are pressed together, the outlet pipe 10 formed in the other outer cylinder 3 is inserted. The laser beam L is irradiated from the inside of the flange portion 5 through the hole 15. If the inlet pipe 9 or the outlet pipe 10 is present when the laser beam L is irradiated, these hinder the irradiation of the laser beam L. Therefore, the inlet pipe 9 and the outlet pipe 10 are assembled after welding with the laser beam L. That is, the partition wall 6 is arranged and fixed in advance in the one outer cylinder 2 as described above, and after the laser beam irradiation, the inlet pipe 9 and the outlet pipe 10 are inserted, and both pipes 9 and 10 are inserted from both insides. 9 and 10 are caulked to the partition wall 6 and fixed by caulking joint 11.
[0062]
According to this embodiment, the back bead by laser penetration welding can be visually confirmed from the outside of the silencer 1.
[0063]
Such a welding method shown in FIG. 5 may be applied to each of the embodiments.
In addition to the above embodiments, the following embodiments may be used.
[0064]
The diameter dimensions of the rib-shaped flange portions 5A and 5B shown in FIGS. 2 and 3 are set slightly larger than the diameter dimension of the one flange portion 4, and the one flange portion 4 is formed by the rib-shaped flange portions 5A and 5B. It is good also as a press-fit type which makes both flange parts closely_contact | adhere while expanding a diameter.
[0065]
Moreover, in the flange part shown in FIGS. 1-4 , after making both flange parts contact, it is a spinning process, a swaging process, etc. toward the other flange part 5, 5A-5D from the outer side of one flange part 4. Thus, the diameter reduction processing may be performed to squeeze both flange portions so that both flange portions can be gripped.
[0066]
Further, as shown in FIG. 6 , two welding torches for emitting laser light L in each of the above-described embodiments are arranged at positions facing each other at approximately 180 ° in the circumferential direction of the silencer 1, and the two welding torches. 21 and 22 may be run simultaneously in the same direction along the circumferential direction by half a cycle, and welding a and welding b may be performed simultaneously by half a cycle.
[0067]
As a result, the welding time is reduced by half compared to the case where the entire circumference is welded with one welding torch. Moreover, the heat input balance is good, work distortion (thermal deformation) due to welding heat can be suppressed, and the adhesiveness between both flanges increases.
[0068]
Note that three or more welding torches may be provided at equal intervals.
Figure 7 shows an embodiment of the inspection method of the laser penetration welding in the embodiment shown in FIG. 1 to FIG.
[0069]
In the embodiment shown in FIGS. 1 to 4, since the back wave (back bead) generated by laser penetration welding is formed inside the silencer 1, the back wave is not visually confirmed from the outside of the silencer 1. In addition, methods such as overflow deep injury cannot be taken.
[0070]
Therefore, as shown in FIG. 7 , for example, when the optical sensor 31 is inserted and arranged in the silencer 1 through the inlet pipe 9 and the laser welding W by the laser beam penetrates in the flange portions 4 and 5, The arc coming out of is detected by the optical sensor 31 or the like, and through welding is confirmed. In addition, you may make it confirm with the heat which generate | occur | produces in the silencer 1 at the time of penetration welding using a thermal sensor instead of the said optical sensor 31. FIG.
[0071]
【The invention's effect】
As described above, according to the first aspect of the present invention, both flange portions are inclined at a predetermined angle other than a right angle with respect to the shaft center of the silencer. By laser welding while pressing in the proximity direction along the axial direction of the vessel, even if the angle between the flange parts and the flange surface accuracy vary, both flange parts deform and mate with each other The gap between the overlapping surfaces is eliminated over the entire circumference, and stable laser welding is possible.
[0072]
In a further, outer wall of the muffler, the two bowl-like material, for constitution fitted in each opening side, well only welding the flange portions at the one of the fitting portion, the weld portion Is one place, and the laser welding process can be reduced.
[0076]
According to invention of Claim 3 , the manufacturing method of the silencer which exhibits the said effect can be provided.
[Brief description of the drawings]
1A and 1B show a first embodiment of the present invention, in which FIG. 1A is a cross-sectional view of the entire silencer, FIG. 1B is an enlarged cross-sectional view of a round portion B in FIG. 1A, and FIGS. Sectional drawing which shows penetration welding.
FIG. 2 is an enlarged cross-sectional view of a joint portion showing a second embodiment of the present invention.
FIG. 3 is an enlarged cross-sectional view of a joint portion showing a third embodiment of the present invention.
FIG. 4 is an enlarged sectional view of a joint portion showing a fourth embodiment of the present invention.
FIG. 5 is a cross-sectional view showing an embodiment of a laser beam irradiation method in the present invention.
FIG. 6 is a diagram illustrating an embodiment of a welding method according to the present invention.
FIG. 7 is a diagram for explaining an embodiment of a welding inspection method according to the present invention.
FIG. 8 is a cross-sectional view showing a first conventional structure.
FIG. 9 is a cross-sectional view showing a second conventional structure.
FIG. 10 is a sectional view showing a third conventional structure.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Silencer 2, 3 Outer cylinder 2c, 3c Plate-shaped member 4 Flange part 5, 5A-5E Flange part L Laser beam XX The axis of a silencer

Claims

In a silencer that integrally joins two outer cylinders formed by processing a plate material into a bowl shape by laser welding, the outer peripheral edge of one outer cylinder is not perpendicular to the axis of the silencer. A flange portion that is inclined at a predetermined angle and is bent outward, and a flange portion that is inclined at a predetermined angle other than a right angle with respect to the shaft center of the silencer and is bent inward at the peripheral edge of the opening of the other outer cylinder The silencer is characterized in that a part is formed, the opening sides of the two outer cylinders face each other, and the flanges are overlapped with each other and penetrated by laser welding.

The partition wall is fixed to the outer cylinder on the side having the flange located on the outside of the two outer cylinders, at a position entering the inner side from the opening in the axial direction. The listed silencer.

In a method of manufacturing a silencer in which two outer cylinders formed by processing a plate material into a bowl shape are integrally joined by laser welding, an opening peripheral portion of one outer cylinder is disposed on the axis of the silencer. A flange that is inclined at a predetermined angle other than a right angle and bent outward is formed, and the outer peripheral edge of the other outer cylinder is inclined at a predetermined angle other than a right angle with respect to the axis of the silencer and bent inward. Forming the flange portion, the opening sides of the outer cylinders are opposed to each other, the flange portions are overlapped with each other, and the outer cylinders are pressed toward each other along the axial center while A method of manufacturing a silencer, characterized in that laser light is irradiated from a direction orthogonal to the overlapping surface, and both flange portions are through-welded by laser welding.