JP4247779B2

JP4247779B2 - Laser welding method and apparatus

Info

Publication number: JP4247779B2
Application number: JP2003067489A
Authority: JP
Inventors: 和弘黒木; 重之塚田; 優介大脇
Original assignee: Toyota Motor Corp
Current assignee: Toyota Motor Corp
Priority date: 2003-03-13
Filing date: 2003-03-13
Publication date: 2009-04-02
Anticipated expiration: 2023-03-13
Also published as: JP2004276038A

Description

【０００１】
【発明の属する技術分野】
本発明は、レーザ溶接方法及び装置に関し、特に、本体部とフランジ部が略直交するように夫々金属薄板によって形成して成る第１の部材及び第２の部材を溶接して、燃料タンク等の大型の装置を製造するのに好適なレーザ溶接方法及び装置に係る。
【０００２】
【従来の技術】
燃料タンク等の大型容器の製造に好適なレーザ溶接方法に関し、例えば下記の特許文献１には、隙間なく重ね合わせた両面アルミメッキ鋼板に対しレーザビームを相対的に移動させながら溶接する方法において、相対速度を遅くすることによって溶接強度を向上させることが提案されている。この特許文献１には、アルミメッキ鋼板から成る半殻体のフランジ部を重ね合わせて溶接する方法として、三種の代表例が以下のように説明されている。
【０００３】
先ず、（Ａ）として、レーザの照射方向をフランジ面方向に対して略直角方向とし、レーザ溶接機を周縁に沿って全周に亘って移動させながら溶接する方法が示され、（Ｂ）として、レーザの照射方向をフランジ面と略平行にし、両フランジ部の端部の接合面端部に向けて照射しながら溶接機を周縁に沿って全周に亘って移動させ全周を溶接する方法が示されている。更に、（Ｃ）として、フランジ部の張出し幅を変化させ、張出し幅の狭い方の接合端部に向けて斜め方向からレーザ光を照射する方法が示されている。
【０００４】
上記（Ａ）の範疇のレーザ溶接方法として、下記の特許文献２には、立体薄板構造体の２枚の薄板の端部を重ね合わせた状態で、これら両薄板の端部を溶接接合する方法において、レーザー光発生器から光ファイバーで導光されるレーザー光を受ける溶接ヘッドと、その溶接ヘッドの近くに設けられた少なくとも１対の相対向するローラを用い、両薄板の端部を相対向するローラで挟圧した状態で、溶接ヘッドとローラとを両薄板の端部に沿って同期移動させながら、溶接ヘッドからレーザー光を両薄板端部の板厚方向に出射して連続的に溶接する立体薄板構造体の溶接方法が提案されている。
【０００５】
また、上記（Ｂ）の範疇のレーザ溶接方法として、下記の特許文献３には、フランジ継目の所で重なる２つの金属板をフランジ継目の範囲で互いに押付け、溶接過程中に金属板とレーザビームとを互いに動かし、フランジ継目の面にあるレーザビームにより溶接を行い、溶接送り方向においてレーザビームより前にある位置で、金属板を互いに広げ、互いに広げられる金属板の間隙の底の範囲へレーザビームを照射するレーザ溶接方法において、金属板を互いに広げるため、溶接送り方法においてレーザビームより前にある楔状広げ部材を使用するレーザ溶接方法が提案されている。
【０００６】
更に、上記（Ｃ）の範疇における変形例として、下記の特許文献４には、レーザ加工ロボットのロボットアームの先端部に、レーザ加工ヘッドを備えたキャリヤ部材に、それぞれワークの水平面内輪郭及び上下方向面に弾性的に圧接追随する機械的接触追随手段を設けたレーザ加工ロボットのワーク倣い装置が提案されている。これにより、初期のロボット動作プログラムの少数の要点のラフなティーチングのみで、各点間は実際のワーク形状の倣いにより高精度のティーチングが行われる旨記載されている。
【０００７】
【特許文献１】
特許第３２２３１７２号公報
【特許文献２】
特開平５−１５４６７７号公報
【特許文献３】
特許第２９８１７３８号公報
【特許文献４】
特開平９−２４８６８３号公報
【０００８】
【発明が解決しようとする課題】
前掲の特許文献１には、前記（Ａ）乃至（Ｃ）のレーザ溶接方法に関し、夫々の利害得失に言及されており、特許文献１では前記（Ａ）のレーザ溶接方法における改良が提案されている。しかし、前記（Ａ）のレーザ溶接方法では、前掲の特許文献２の溶接方法と同様、フランジ部の幅を広くせざるを得ず、また、溶接後、外観品質を保つため防錆塗装を施す必要がある。前記（Ｂ）のレーザ溶接方法では防錆塗装は不要であるが、レーザ照射位置を保持することが困難である。これに対し、前掲の特許文献３に記載のレーザ溶接方法においては、金属板を互いに広げるための広げ部材を用いているが、その駆動制御は容易ではなく、必ずしも量産に適するものではない。
【０００９】
ここで、前記（Ｂ）のレーザ溶接方法は、本体部とフランジ部が略直交するように夫々金属薄板によって形成して成る第１の部材及び第２の部材を、各々のフランジ部が対向するように配置し、各々のフランジ部の端面間に対し、レーザヘッドからフランジ面に平行にレーザビームを照射して第１の部材及び第２の部材を接合するレーザ溶接方法ということができる。このレーザ溶接方法によれば、加工対象は円形に限らず複雑な３次元形状であっても、また、フランジ部の幅を然程広くすることなく、適切に溶接することができるので、燃料タンクの製造に好適である。
【００１０】
一方、前掲の特許文献４に記載のワーク倣い装置は、特許文献３において必須とされる広げ部材を必要とすることなく、レーザ照射位置を保持することができるが、特許文献４に記載の装置は、外形輪郭に沿ってその周縁を溶接する場合に用いられるものであることから、この溶接対象特有の構造であり、前記（Ｂ）又は（Ｃ）のレーザ溶接方法にそのまま適用することはできず、また、そのような適用に関する記載は見当たらない。
【００１１】
例えば、前掲の特許文献４には、レーザ加工ロボットのロボットアームの先端部に配設されたキャリア部材に、それぞれ一対のサイドローラ及び上下ローラ３がＺ方向軸心及びＸ方向軸心回りに自由回転可能に配設されていると記載され、加工ヘッドはワークとサイドローラ及び上下ローラにより、ワーク外形輪部（輪郭）に倣って溶接加工を実施することができる旨記載されている。しかし、このようなワーク倣い装置を前記（Ｂ）のレーザ溶接方法に適用するときには、ワーク外形輪郭とフランジ部の相違に対する適切な対応が必要であり、直ちに具体的手段が想起されるものではない。
【００１２】
そこで、本発明は、本体部とフランジ部が略直交するように夫々金属薄板によって形成して成る第１の部材及び第２の部材を、各々のフランジ部が対向するように配置し、各々のフランジ部の端面間に対し、レーザヘッドからフランジ面に平行にレーザビームを照射して接合するレーザ溶接方法において、簡単な構成で迅速且つ適切に第１の部材と第２の部材を溶接接合し得るようにすることを課題とする。
【００１３】
また、本発明は、簡単な構成で迅速且つ適切に上記第１の部材と第２の部材を容易に溶接接合し得るレーザ溶接装置を提供することを別の課題とする。
【００１４】
【課題を解決するための手段】
上記課題を解決するため、本発明のレーザ溶接方法は、請求項１に記載のように、本体部とフランジ部が略直交するように夫々金属薄板によって形成して成る第１の部材及び第２の部材を、各々のフランジ部が対向するように配置し、各々のフランジ部の端面間に対し、レーザヘッドから当該フランジ部のフランジ面に平行にレーザビームを照射して前記第１の部材及び第２の部材を接合するレーザ溶接方法において、前記第１の部材の本体部に当接する第１案内部、及び前記第１の部材のフランジ部に当接する第１把持部を有し、該第１把持部が前記第１の部材のフランジ部に当接した状態で前記各々のフランジ部の端面間に対し、前記各々のフランジ部のフランジ面に平行に前記レーザヘッドが指向する所定の位置関係に、前記レーザヘッドを支持する第１の支持部材と、該第１の支持部材に対し相対移動可能に支持し、前記第２の部材の本体部に当接する第２案内部、及び前記第２の部材のフランジ部に当接する第２把持部を有し、該第２把持部が前記第２の部材のフランジ部に当接したときに前記第１把持部と対向するように配置する第２の支持部材とを備え、前記レーザヘッドが支持された前記第１の支持部材に対して前記第２の支持部材を駆動し、前記第１把持部と前記第２把持部との間に前記第１及び第２の部材のフランジ部を挟持した状態で、前記各々のフランジ部の端面間に対し、前記各々のフランジ部のフランジ面に平行に前記レーザヘッドからレーザビームを照射しながら、前記各々のフランジ部に沿って前記第１及び第２の支持部材を前記第１及び第２の部材に対して相対駆動するものである。
【００１５】
前記レーザ溶接方法において、請求項２に記載のように、前記第２把持部が前記第２の部材のフランジ部に当接したときに前記第１把持部の方向に所定の圧力で付勢し、該付勢状態を維持するように、前記第２の支持部材を前記第１の支持部材に支持するとよい。
【００１６】
尚、前記第１及び第２の案内部は着脱可能なボールユニットによって構成することができる。また、前記第１及び第２の把持部はローラ部材によって構成し、ローラ部材がフランジ面を転動しながらフランジ部を挟持するように構成するとよい。そして、ローラ部材によって第１及び第２の部材のフランジ部を挟持したときに、各フランジ部が弾性変形し端面間に微少間隙が形成されるように構成するとよい。
【００１７】
あるいは、本発明のレーザ溶接方法として、請求項３に記載のように、本体部とフランジ部が略直交するように夫々金属薄板によって形成して成る第１の部材及び第２の部材を、各々のフランジ部が対向するように配置し、各々のフランジ部の端面間に対し、レーザヘッドから当該フランジ部のフランジ面に平行にレーザビームを照射して前記第１の部材及び第２の部材を接合するレーザ溶接方法において、夫々前記第１及び第２の部材のフランジ部に平行な誘導部を有し、前記第１及び第２の部材の本体部に対し略平行で、前記第１及び第２の部材のフランジ部を挟持するように配置する第３の部材及び第４の部材と、前記第３の部材の誘導部に当接する第１被誘導部、及び前記第４の部材の誘導部に当接する第２被誘導部を有し、該第２被誘導部と前記第１被誘導部との間の所定の位置に前記レーザヘッドを配置すると共に、前記各々のフランジ部の端面間に対し、前記各々のフランジ部のフランジ面に平行に前記レーザヘッドが指向する所定の位置関係に、前記レーザヘッドを支持する支持部材とを備え、前記第３の部材と前記第４の部材との間に前記第１及び第２の部材のフランジ部を挟持した状態で、前記各々のフランジ部の端面間に対し、前記各々のフランジ部のフランジ面に平行に前記レーザヘッドからレーザビームを照射しながら、前記各々のフランジ部に沿って前記支持部材を前記第１乃至第４の部材に対して相対駆動するように構成してもよい。
【００１８】
例えば、前記誘導部としては、前記第３の部材及び第４の部材の外側表面に形成するＶ字溝とし、前記第１被誘導部及び第２被誘導部としては、Ｖ字溝に合致するＶ字断面を有するローラ部材とし、該ローラ部材を前記Ｖ字溝に沿って回動するように構成するとよい。
【００１９】
そして、本発明のレーザ溶接装置としては、請求項４に記載のように、本体部とフランジ部が略直交するように夫々金属薄板によって形成して成る第１の部材及び第２の部材を、各々のフランジ部が対向するように配置し、各々のフランジ部の端面間に対し、レーザヘッドから当該フランジ部のフランジ面に平行にレーザビームを照射して前記第１の部材及び第２の部材を接合するレーザ溶接装置において、前記第１の部材の本体部に当接する第１案内部、及び前記第１の部材のフランジ部に当接する第１把持部を有し、該第１把持部が前記第１の部材のフランジ部に当接した状態で前記各々のフランジ部の端面間に対し、前記各々のフランジ部のフランジ面に平行に前記レーザヘッドが指向する所定の位置関係に、前記レーザヘッドを支持する第１の支持部材と、該第１の支持部材に対し相対移動可能に支持し、前記第２の部材の本体部に当接する第２案内部、及び前記第２の部材のフランジ部に当接する第２把持部を有し、該第２把持部が前記第２の部材のフランジ部に当接したときに前記第１把持部と対向するように配置する第２の支持部材と、前記レーザヘッドが支持された前記第１の支持部材に対して前記第２の支持部材を駆動し、前記第１把持部と前記第２把持部との間に前記第１及び第２の部材のフランジ部を挟持した状態で、前記各々のフランジ部の端面間に対し、前記各々のフランジ部のフランジ面に平行に前記レーザヘッドからレーザビームを照射しながら、前記各々のフランジ部に沿って前記第１及び第２の支持部材を前記第１及び第２の部材に対して相対駆動する駆動手段を備えることとしたものである。
【００２０】
更に、請求項５に記載のように、前記第２の支持部材を前記第１の支持部材に対し揺動自在に支持し、前記駆動手段は、前記第２把持部が前記第２の部材のフランジ部に当接したときに前記第１把持部の方向に所定の圧力で付勢し、該付勢状態を維持するように、前記第２の支持部材を駆動するとよい。
【００２１】
前記駆動手段としては、例えばロボット装置のロボットアームに装着した構成とし、例えばリンク機構を介して、前記第２の支持部材を前記第１の支持部材に対し揺動可能に支持すると共に、例えば空気圧シリンダによって前記リンク機構を駆動して、前記第１及び第２の部材のフランジ部を挟持するように構成することができる。
【００２２】
あるいは、本発明のレーザ溶接装置としては、請求項６に記載のように、本体部とフランジ部が略直交するように夫々金属薄板によって形成して成る第１の部材及び第２の部材を、各々のフランジ部が対向するように配置し、各々のフランジ部の端面間に対し、レーザヘッドから当該フランジ部のフランジ面に平行にレーザビームを照射して前記第１の部材及び第２の部材を接合するレーザ溶接装置において、夫々前記第１及び第２の部材のフランジ部に平行な誘導部を有し、前記第１及び第２の部材の本体部に対し略平行で、前記第１及び第２の部材のフランジ部を挟持するように配置する第３の部材及び第４の部材と、前記第３の部材の誘導部に当接する第１被誘導部、及び前記第４の部材の誘導部に当接する第２被誘導部を有し、該第２被誘導部と前記第１被誘導部との間の所定の位置に前記レーザヘッドを配置すると共に、前記各々のフランジ部の端面間に対し、前記各々のフランジ部のフランジ面に平行に前記レーザヘッドが指向する所定の位置関係に、前記レーザヘッドを支持する支持部材と、前記第３の部材と前記第４の部材との間に前記第１及び第２の部材のフランジ部を挟持した状態で、前記各々のフランジ部の端面間に対し、前記各々のフランジ部のフランジ面に平行に前記レーザヘッドからレーザビームを照射しながら、前記各々のフランジ部に沿って前記支持部材を前記第１乃至第４の部材に対して相対駆動する駆動手段を備えたものとしてもよい。例えば、前記第３の部材及び第４の部材の外側表面にＶ字溝を形成して前記誘導部とすると共に、Ｖ字溝に合致するＶ字断面を有するローラ部材を前記第１被誘導部及び第２被誘導部とし、該ローラ部材を前記Ｖ字溝に沿って回動するように構成することができる。
【００２３】
【発明の実施の形態】
以下、本発明の実施形態について図面を参照して説明する。図１乃至図９は、本発明の一実施形態に係るレーザ溶接装置に関し、燃料タンクの溶接に供される。先ず、燃料タンク外周の溶接部を拡大して示す図１において、二分割の燃料タンクのアッパシェル１００とロアシェル２００が夫々本発明の第１の部材及び第２の部材を構成している。アッパシェル１００及びロアシェル２００は、何れも金属薄板、例えばアルミメッキ鋼板によって半割容器状に形成されており、本体部１０１及び２０１とフランジ部１０２及び２０２とが夫々略直交するように形成されている。
【００２４】
これらのアッパシェル１００及びロアシェル２００の溶接時には、各々のフランジ部１０２及び２０２が対向するように配置される。そして、各々のフランジ部１０２及び２０２の端面１０３及び２０３間に対し、レーザヘッド３１から各フランジ部１０２及び２０２のフランジ面に平行にレーザビームが照射されるように、レーザユニット３０が配置される。このレーザユニット３０は、本発明の第１の支持部材を構成する支持アーム１０に支持され、レーザヘッド３１が支持アーム１０に対し所定の位置関係（これについては後述する）となるように固定されている。また、本発明の第２の支持部材を構成するＬ字状の揺動アーム２０が、支持アーム１０に対し揺動可能に支持されている。
【００２５】
ここで、上記支持アーム１０、揺動アーム２０及びレーザユニット３０を含むレーザ装置全体の構成について、図２乃至図４を参照して説明する。図２に示すように、支持アーム１０はフローティング機構４０を介してロボットアーム５０に装着されている。ロボットアーム５０はロボット装置（図示せず）の一部を構成するものであり、周知であるので説明は省略する。支持アーム１０は、フローティグ機構４０に固着されたアーム本体１０ｂと、その先端に接合されたＬ字状のフィンガ部１０ａを有し、これに垂直にブラケット１０ｃ及び１０ｄが支持されている。そして、ブラケット１０ｃには、レーザユニット３０が固定され、アーム本体１０ｂと平行に支持され、レーザヘッド３１がフィンガ部１０ａに対し図２に示す位置関係に保持されている。また、ブラケット１０ｄには、揺動アーム２０が揺動可能に支持されている。
【００２６】
揺動アーム２０は、Ｌ字状のフィンガ部２０ａとＬ字状のアーム本体２０ｂが接合されてクランク形状とされ、アーム本体２０ｂは、その角部にて軸Ｃ１を中心に回動可能に、ブラケット１０ｄに軸支されている。更に、アーム本体２０ｂの先端には、駆動アーム２０ｃの一端が軸Ｃ２を中心に回動可能に軸支されている。この駆動アーム２０ｃの他端は駆動ユニット６０の空気圧シリンダ６１に連結されており、空気圧シリンダ６１によって図２の水平方向に移動し得るように構成されている。尚、空気圧シリンダ６１に代えて、油圧シリンダを用いてもよく、電動モータを用いてもよい。而して、本実施形態においては、アーム本体２０ｂ及び駆動アーム２０ｃによって揺動リンク機構が構成され、空気圧シリンダ６１による駆動アーム２０ｃの移動に応じて、アーム本体２０ｂが軸Ｃ１を中心に揺動し、フィンガ部２０ａの先端がフィンガ部１０ａの先端に対し近接又は離隔するように構成されている。
【００２７】
次に、図１に戻り、支持アーム１０のフィンガ部１０ａの先端には、本発明の第１把持部を構成するローラ部材１１が回動自在に支持され、支持アーム１０のフィンガ部１０ａの角部には、本発明の第１案内部を構成するボールユニット１２が装着されている。同様に、揺動アーム２０のフィンガ部２０ａの先端には、本発明の第２把持部を構成するローラ部材２１が回動自在に支持され、角部には、本発明の第２案内部を構成するボールユニット２２が装着されている。
【００２８】
ローラ部材１１及び２１は、図１に示すように、夫々ローラ１１ａ及び２１ａがベアリング１１ｂ及び２１ｂを介して軸１１ｃ及び２１ｃに回動自在に支持され、軸１１ｃ及び２１ｃはフィンガ部１０ａ及び２０ａの先端部に固定されている。これらのローラ部材１１及び２１は、溶接作動時には、夫々フランジ部１０２及び２０２に当接すると共に、両者が対向するように配置される。
【００２９】
一方、ボールユニット１２及び２２は、図５乃至図７に示すように構成されており、フィンガ部１０ａ及びフィンガ部２０ａに対し着脱可能に支持されている。即ち、ボール１２ａがベース１２ｂに収容され、所定距離外方に突出した状態で回転可能に支持されており、フィンガ部１０ａに形成された凹部にベース１２ｂが嵌合され、ボルトＢによって固定されている。従って、ベース１２ｂの厚さ（図５の左右方向の寸法）を適宜設定し、あるいは種々の厚さのベースを用意しておき、その中から適宜選択することにより、ボール１２ａのフィンガ部１０ａからの突出距離を適宜設定することができる。これにより、ローラ部材１１及び２１によって把持する位置を、フランジ部１０２及び２０２の幅に応じて適宜調整することができる。
【００３０】
上記のボールユニット１２及び２２は、溶接作動時には、夫々本体部１０１及び２０１の外側表面に当接するように配置される。そして、ボール１２ａはアッパシェル１００の本体部１０１の外側表面上を滑らかに移動するので、フィンガ部１０ａ（ひいてはローラ部材１１）を、本体部１０１に対し所定の間隙を維持し乍ら、円滑に移動させることができる。従って、ローラ部材１１のローラ１１ａは本体部１０１から所定距離離隔した位置でフランジ部１０２に当接し、この当接位置からフランジ部１０２の端面１０３までの距離は、成形時のフランジ部１０２の幅が略均一であれば、略一定に維持することができる。例えば、周長が１ｍ以上の燃料タンクを対象とする本実施形態においても５乃至２０ｍｍの範囲で一定に維持することができる。尚、ボールユニット２２も同一の構成であるので、説明は省略する。
【００３１】
而して、上記の構成になるレーザ溶接装置によってアッパシェル１００とロアシェル２００を溶接接合する場合には、図８に示すように、先ずアッパシェル１００及びロアシェル２００のフランジ部１０２及び２０２が対向するように配置する。このとき、レーザ溶接装置の駆動アーム２０ｃは図８の左方の初期位置に保持されており、揺動アーム２０の先端に装着されたローラ部材２１が、支持アーム１０の先端に装着されたローラ部材１１から最も離隔した位置に保持された状態にある。
【００３２】
そして、ロボットアーム５０を駆動し、ボールユニット１２のボール１２ａが本体部１０１の外側表面に当接する共に、ローラ部材１１のローラ１１ａがフランジ部１０２に当接するように支持アーム１０を配置すると、フランジ部１０２及び２０２の端面１０３及び２０３間に対し、フランジ面に平行にレーザヘッド３１が指向する図８の位置関係となる。この状態で、空気圧シリンダ６１を図８の右方に駆動し、駆動アーム２０ｃを同方向に駆動すると、揺動アーム２０は軸Ｃ１を中心に右回転で揺動する。従って、図９に示すように、ローラ部材２１がフランジ部２０２に当接するまで揺動アーム２０を駆動し所定の圧力で付勢した状態に維持する。このとき、ローラ部材２１はローラ部材１１に対向する位置となるので、両者によってフランジ部１０２及び２０２を所定の圧力で挟持する状態となる。この結果、図１に示すローラ部材１１及び２１のフランジ部１０２及び２０２への当接位置から端面１０３及び２０３までの間が弾性変形し、端面１０３及び２０３の位置で約０．１ｍｍの微少間隙が形成される。
【００３３】
而して、ローラ部材１１及び２１によってフランジ部１０２及び２０２を挟持した状態で、上記端面１０３及び２０３間に対し、レーザヘッド３１からフランジ部１０２及び２０２のフランジ面に平行にレーザビームを照射し乍ら、フランジ部１０２及び２０２に沿って移動させることにより、３次元形状の溶接対象に対しても連続して溶接することができる。この間、ローラ部材１１及び２１がフランジ面を転動しながら移動すると共に、ボール１２ａ及び２２ａが本体部１０１及び２０１に対し所定の間隙を維持し乍ら、円滑に移動するので、レーザヘッド３１を上記端面１０３及び２０３間に対し所定の位置関係に維持した状態で、比較的高速（例えば３ｍ／分以上）で移動し乍ら適切に溶接することができる。しかも、この溶接時に発生する蒸気は上記端面１０３及び２０３間の微少間隙から放出されるので安定した接合状態を確保することができる。尚、必要に応じ、上記端面１０３及び２０３間の微少間隙を略零にすることもできる。
【００３４】
次に、本発明の他の実施形態に係るレーザ溶接装置を図１０乃至図１３を参照して説明する。本実施形態においては、前述のアッパシェル１００及びロアシェル２００を所定の間隙を隔てて囲繞するように押え型３００及び４００が配置され、これらが本発明の第３の部材及び第４の部材を構成している。これらの押え型３００及び４００は、開口端部３０２及び４０２が前述のローラ１１ａ及び１１ｂの先端部と同様の断面形状に形成されており、これらの開口端部３０２及び４０２によってフランジ部１０２及び２０２を所定の圧力で挟持するように構成されている。更に、押え型３００及び４００の外側表面には、本発明の誘導部として、フランジ部１０２及び２０２から所定距離隔てて平行に、Ｖ字溝３０１及び４０１が形成されている。これらのＶ字溝３０１及び４０１は、溶接面の３／１００乃至１０／１００ｍｍの精度で形成することが望ましい。
【００３５】
そして、前述の支持アーム１０に代えて支持アーム７０がフローティング機構４０に固定されると共に、揺動アーム２０に代えて支持アーム８０が設けられ、フローティング機構４０に固定されている。即ち、本実施形態においては、図１１に示すように支持アーム７０及び８０は左右対称で、何れもフローティング機構４０に固定されており、これらによって支持部材が構成されている。従って、前述の駆動ユニット６０は備えていない。また、本実施形態においては、前述のローラ部材１１及び２１並びにボールユニット１２及び２２は備えておらず、図１１に示すＶ字溝３０１及び４０１に合致するＶ字断面を有するローラ部材７１及び８１が支持アーム７０及び８０に回動自在に支持されている。
【００３６】
即ち、図１０に示すように、支持アーム７０及び８０の支持部７０ａ及び８０ａには、夫々本発明の第１及び第２被誘導部を構成するローラ部材７１及び８１が回動自在に支持されている。ローラ部材７１及び８１は、夫々Ｖ字断面を有するローラ７１ａ及び８１ａがベアリング７１ｂ及び８１ｂを介して軸７１ｃ及び８１ｃに回動自在に支持され、軸７１ｃ及び８１ｃは支持部７０ａ及び８０ａの先端部に固定されている。これらのローラ部材７１及び８１は、ローラ７１ａ及び８１ａがＶ字溝３０１及び４０１に嵌合するように配置される。従って、レーザヘッド３１はＶ字溝３０１とＶ字溝４０１との間に配置され、所定の位置関係、即ち、フランジ部１０２及び２０２の端面１０３及び２０３間に対し、フランジ面に平行に先端が指向するように保持される。尚、図１０乃至図１３においては、前述の図１乃至図４に記載の部材と実質的に同じ部材については同一の符号を付している（尚、７０ｂ及び８０ｂはアーム本体）。
【００３７】
而して、図１０乃至図１３に記載の構成になるレーザ溶接装置によってアッパシェル１００とロアシェル２００を溶接接合する場合には、図１０に示すように、先ずアッパシェル１００及びロアシェル２００のフランジ部１０２及び２０２が対向するように配置する。そして、これらのアッパシェル１００及びロアシェル２００を所定の間隙を隔てて囲繞するように、押え型３００及び４００を配置し、開口端部３０２及び４０２によってフランジ部１０２及び２０２を所定の圧力で挟持する。この結果、図１０に示す開口端部３０２及び４０２のフランジ部１０２及び２０２への当接位置から端面１０３及び２０３までの間が弾性変形し、端面１０３及び２０３の位置で約０．１ｍｍの微少間隙が形成される。
【００３８】
この状態でロボットアーム５０を駆動し、ローラ部材７１及び８１が押え型３００及び４００のＶ字溝３０１及び４０１に嵌合するように、支持アーム７０及び８０を配置すると、レーザヘッド３１はフランジ部１０２及び２０２の端面１０３及び２０３間に対し、フランジ面に平行に指向する。而して、ローラ部材７１及び８１はＶ字溝３０１及び４０１に誘導され、押え型３００及び４００ひいてはアッパシェル１００及びロアシェル２００の本体部１０１及び２０１に対し所定の間隙を維持し乍ら、円滑に移動する。
【００３９】
而して、レーザヘッド３１からフランジ部１０２及び２０２のフランジ面に平行にレーザビームを照射し乍ら、フランジ部１０２及び２０２に沿って移動させることにより、連続して溶接することができる。この間、レーザヘッド３１を上記端面１０３及び２０３間に対し所定の位置関係に維持した状態で、移動し乍ら適切に溶接することができる。しかも、この溶接時に発生する蒸気は上記端面１０３及び２０３間の間隙から放出されるので安定した接合状態を確保することができる。尚、上記の何れの実施形態においてもアッパシェル１００及びロアシェル２００を固定しレーザユニット３０側を駆動することとしたが、固定側と駆動側を逆にしてもよく、要は相対的に駆動すればよい。
【００４０】
【発明の効果】
本発明は上述のように構成されているので以下に記載の効果を奏する。即ち、請求項１及び４に記載のレーザ溶接方法及び装置においては、レーザヘッドが支持された第１の支持部材に対して第２の支持部材を駆動し、第１案内部及び第２案内部を第１及び２の部材の本体部に当接させると共に、第１把持部と第２把持部との間に第１及び第２の部材のフランジ部を挟持した状態で、各々のフランジ部の端面間に対し、フランジ面に平行にレーザヘッドからレーザビームを照射しながら、フランジ部に沿って第１及び第２の支持部材を第１及び第２の部材に対して相対駆動するように構成されているので、３次元形状の溶接対象に対しても連続して溶接することができ、フランジ部の端面間に対しフランジ面に平行にレーザヘッドが指向する所定の位置関係に維持した状態で、フランジ部に沿って移動し乍ら、円滑且つ適切に溶接することができる。
【００４１】
前記レーザ溶接方法及び装置において、請求項２及び５に記載のように構成すれば、溶接時に発生する蒸気はフランジ部の端面間の微少間隙から放出されるので安定した接合状態を確保することができる。尚、フランジ部の端面間の微少間隙を略零にすることもできる。
【００４２】
また、請求項３及び６に記載のレーザ溶接方法及び装置においては、第１及び第２の部材の本体部に対し略平行で第１及び第２の部材のフランジ部を挟持するように配置する第３の部材及び第４の部材と、これらの誘導部に当接する第１及び第２の被誘導部を有し、これらの間の所定の位置にレーザヘッドを配置すると共に、各々のフランジ部の端面間に対し、フランジ面に平行にレーザヘッドが指向する所定の位置関係に、レーザヘッドを支持する支持部材とを備え、第３の部材と第４の部材との間に第１及び第２の部材のフランジ部を挟持した状態で、各々のフランジ部の端面間に対しフランジ面に平行にレーザヘッドからレーザビームを照射しながら、フランジ部に沿って支持部材を第１乃至第４の部材に対して相対駆動するように構成されているので、フランジ部の端面間に対しフランジ面に平行にレーザヘッドが指向する所定の位置関係に維持した状態で、フランジ部に沿って移動し乍ら、円滑且つ適切に溶接することができる。
【図面の簡単な説明】
【図１】本発明の一実施形態に係るレーザ溶接装置において、燃料タンク外周の溶接部を拡大して示す一部断面図である。
【図２】本発明の一実施形態に係るレーザ溶接装置の正面図である。
【図３】本発明の一実施形態に係るレーザ溶接装置の側面図である。
【図４】本発明の一実施形態に係るレーザ溶接装置の底面図である。
【図５】本発明の一実施形態に係るレーザ溶接装置に供するボールユニットの一例を示す断面図である。
【図６】本発明の一実施形態に係るレーザ溶接装置に供するボールユニットの一例を示す平面図である。
【図７】本発明の一実施形態に係るレーザ溶接装置に供するボールユニットの一例を示す側面図である。
【図８】本発明の一実施形態に係るレーザ溶接装置の溶接作動前の状態を示す正面図である。
【図９】本発明の一実施形態に係るレーザ溶接装置の溶接作動状態を示す正面図である。
【図１０】本発明の他の実施形態に係るレーザ溶接装置において、燃料タンク外周の溶接部を拡大して示す一部断面図である。
【図１１】本発明の他の実施形態に係るレーザ溶接装置の正面図である。
【図１２】本発明の他の実施形態に係るレーザ溶接装置の側面図である。
【図１３】本発明の他の実施形態に係るレーザ溶接装置の底面図である。
【符号の説明】
１０支持アーム，２０揺動アーム，１１，２１ローラ部材，
１２，２２ボールユニット，３０レーザユニット，
３１レーザヘッド，４０フローティング機構，
５０ロボットアーム，６０駆動ユニット，６１空気圧シリンダ，
７１，８１ローラ部材，１００アッパシェル，２００ロアシェル，
１０１，２０１本体部，１０２，２０２フランジ部，
３００，４００押え型，３０１，４０１Ｖ字溝[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a laser welding method and apparatus, and in particular, welds a first member and a second member formed by a thin metal plate so that a main body portion and a flange portion are substantially orthogonal to each other, such as a fuel tank. The present invention relates to a laser welding method and apparatus suitable for manufacturing a large apparatus.
[0002]
[Prior art]
Regarding a laser welding method suitable for manufacturing a large container such as a fuel tank, for example, in Patent Document 1 below, in a method of welding while moving a laser beam relative to a double-sided aluminized steel sheet stacked without a gap, It has been proposed to improve the welding strength by reducing the relative speed. In this Patent Document 1, three types of typical examples are described as follows as a method of overlapping and welding the flange portions of a half-shell body made of an aluminized steel plate.
[0003]
First, as (A), the laser irradiation direction is set to a direction substantially perpendicular to the flange surface direction, and a method of welding while moving the laser welding machine along the entire circumference is shown as (B). A method of welding the entire circumference by moving the welding machine along the entire circumference while irradiating the laser irradiation direction substantially parallel to the flange surface and irradiating toward the end of the joint surface of both flange portions. It is shown. Further, (C) shows a method of changing the overhang width of the flange portion and irradiating the laser beam from an oblique direction toward the joint end portion having the narrow overhang width.
[0004]
As a laser welding method within the category of (A), the following Patent Document 2 discloses a method in which the ends of two thin plates of a three-dimensional thin plate structure are welded and joined together. In this embodiment, a welding head that receives laser light guided by an optical fiber from a laser light generator and at least one pair of opposing rollers provided in the vicinity of the welding head are used to oppose the ends of both thin plates. While the pressure is sandwiched between the rollers, the welding head and the roller are synchronously moved along the ends of the two thin plates, and laser light is emitted from the welding head in the thickness direction of the two thin plate ends to continuously weld. A welding method for a three-dimensional thin plate structure has been proposed.
[0005]
In addition, as a laser welding method in the category (B), in Patent Document 3 below, two metal plates that overlap at a flange seam are pressed against each other within the flange seam, and the metal plate and the laser beam are welded during the welding process. Are moved to each other, welding is performed with a laser beam on the surface of the flange joint, the metal plates are spread out at a position in front of the laser beam in the welding feed direction, and the laser is applied to the bottom area of the gap between the metal plates that can be spread out. In a laser welding method for irradiating a beam, a laser welding method using a wedge-shaped spreading member in front of a laser beam in a welding feed method has been proposed in order to spread metal plates.
[0006]
Further, as a modification in the category of (C) above, Patent Document 4 below discloses that the tip of the robot arm of a laser processing robot is provided with a carrier member equipped with a laser processing head, the contour in the horizontal plane of the workpiece, There has been proposed a workpiece copying apparatus for a laser processing robot provided with mechanical contact tracking means for elastically pressing and tracking a direction surface. Thus, it is described that high-precision teaching is performed between each point by copying the actual workpiece shape only by rough teaching of a few main points of the initial robot operation program.
[0007]
[Patent Document 1]
Japanese Patent No. 3223172
[Patent Document 2]
Japanese Patent Laid-Open No. 5-154677
[Patent Document 3]
Japanese Patent No. 2981738
[Patent Document 4]
JP-A-9-248683
[0008]
[Problems to be solved by the invention]
Patent Document 1 mentioned above refers to the advantages and disadvantages of the laser welding methods (A) to (C) described above, and Patent Document 1 proposes an improvement in the laser welding method (A). Yes. However, in the laser welding method of (A), the width of the flange portion must be widened as in the above-described welding method of Patent Document 2, and rust-proof coating is applied after welding to maintain the appearance quality. There is a need. The laser welding method (B) does not require rust-proof coating, but it is difficult to maintain the laser irradiation position. On the other hand, in the laser welding method described in Patent Document 3 described above, a spreading member for spreading the metal plates is used, but its drive control is not easy and is not necessarily suitable for mass production.
[0009]
Here, in the laser welding method of (B), each flange portion faces the first member and the second member that are formed of metal thin plates so that the main body portion and the flange portion are substantially orthogonal to each other. It can be said that the laser welding method is arranged such that the first member and the second member are joined by irradiating a laser beam from the laser head in parallel to the flange surface between the end faces of the flange portions. According to this laser welding method, even if the object to be processed is not limited to a circular shape but has a complicated three-dimensional shape, and it is possible to perform appropriate welding without increasing the width of the flange portion, the fuel tank It is suitable for manufacturing.
[0010]
On the other hand, the workpiece copying apparatus described in Patent Document 4 described above can hold the laser irradiation position without requiring a spreading member essential in Patent Document 3, but the apparatus described in Patent Document 4 Since this is used when welding the periphery along the outer contour, it is a structure unique to this welding object, and can be directly applied to the laser welding method of (B) or (C). In addition, there is no description regarding such application.
[0011]
For example, in the above-mentioned Patent Document 4, a pair of side rollers and upper and lower rollers 3 are free to move around the Z-direction axis and the X-direction axis, respectively, on the carrier member disposed at the tip of the robot arm of the laser processing robot. It is described that it is rotatably arranged, and it is described that the machining head can perform welding by following the workpiece outer ring portion (contour) by the workpiece, the side roller, and the upper and lower rollers. However, when such a workpiece copying apparatus is applied to the laser welding method (B) described above, it is necessary to appropriately cope with the difference between the workpiece outer contour and the flange portion, and no specific means are immediately conceived. .
[0012]
Therefore, the present invention arranges the first member and the second member formed by metal thin plates so that the main body portion and the flange portion are substantially orthogonal to each other so that the respective flange portions face each other. In a laser welding method in which a laser beam is irradiated from a laser head in parallel to the flange surface between the end faces of the flange portion, the first member and the second member are welded and joined quickly and appropriately with a simple configuration. The problem is to get it.
[0013]
It is another object of the present invention to provide a laser welding apparatus that can easily weld and join the first member and the second member quickly and appropriately with a simple configuration.
[0014]
[Means for Solving the Problems]
In order to solve the above-mentioned problems, a laser welding method according to the present invention includes a first member and a second member each formed by a thin metal plate so that the main body portion and the flange portion are substantially orthogonal to each other. Are arranged so that each flange portion faces each other, and a laser beam is irradiated in parallel from the laser head to the flange surface of the flange portion between the end surfaces of each flange portion, and the first member and In the laser welding method for joining the second member, the first member has a first guide portion that contacts the main body portion of the first member, and a first grip portion that contacts the flange portion of the first member. 1 gripping part But Above Of the first member Flange part Between the end faces of the flange portions in contact with each other Whereas The laser head is oriented parallel to the flange surface of each flange portion. Predetermined positional relationship In addition, A first support member that supports the laser head; a second guide portion that is supported so as to be relatively movable with respect to the first support member; and abuts against a main body portion of the second member; and the second member And a second support disposed so as to face the first grip when the second grip is in contact with the flange of the second member. With members, Driving the second support member relative to the first support member on which the laser head is supported; In a state where the flange portions of the first and second members are sandwiched between the first grip portion and the second grip portion, Between each end face of each of the flange portions, While irradiating a laser beam from the laser head parallel to the flange surface of the flange portion, Each The first and second support members are driven relative to the first and second members along the flange portion.
[0015]
In the laser welding method, as described in claim 2, when the second gripping portion comes into contact with the flange portion of the second member, the laser welding method biases the first gripping portion with a predetermined pressure. The second support member may be supported by the first support member so as to maintain the biased state.
[0016]
The first and second guide portions can be constituted by detachable ball units. The first and second gripping portions may be constituted by a roller member, and the roller member may be configured to sandwich the flange portion while rolling on the flange surface. And when the flange part of the 1st and 2nd member is clamped with a roller member, it is good to comprise so that each flange part may be elastically deformed and a micro clearance gap may be formed between end surfaces.
[0017]
Alternatively, as a laser welding method of the present invention, as described in claim 3, the first member and the second member respectively formed by metal thin plates so that the main body portion and the flange portion are substantially orthogonal to each other, The first and second members are arranged so that the flange portions of the flange portions face each other, and a laser beam is irradiated from the laser head in parallel to the flange surfaces of the flange portions between the end faces of the flange portions. In the laser welding method for joining, the first and second members have guide portions parallel to the flange portions of the first and second members, respectively, and are substantially parallel to the main body portions of the first and second members. A third member and a fourth member disposed so as to sandwich the flange portion of the second member, a first guided portion contacting the guiding portion of the third member, and a guiding portion of the fourth member A second guided portion abutting against the second guided portion; Predetermined position between the induction portion first the guided portion Between the end faces of the flange portions Whereas The laser head is oriented parallel to the flange surface of each flange portion. Predetermined positional relationship In addition, A support member for supporting the laser head, and the third member; Above The flange portions of the first and second members are sandwiched between the fourth member and the fourth member. In a state where each flange portion is between the end surfaces of each flange portion, While irradiating a laser beam from the laser head parallel to the flange surface of the flange portion, Each You may comprise so that the said supporting member may be driven relatively with respect to the said 1st thru | or 4th member along a flange part.
[0018]
For example, the guiding part is a V-shaped groove formed on the outer surface of the third member and the fourth member, and the first guided part and the second guided part are matched with the V-shaped groove. A roller member having a V-shaped cross section may be used, and the roller member may be configured to rotate along the V-shaped groove.
[0019]
And as a laser welding apparatus of the present invention, as described in claim 4, the first member and the second member formed by a thin metal plate so that the main body portion and the flange portion are substantially orthogonal to each other, The first member and the second member are arranged so that each flange portion faces each other, and a laser beam is irradiated from the laser head in parallel to the flange surface of the flange portion between the end faces of each flange portion. A first guide portion that contacts the main body portion of the first member, and a first grip portion that contacts the flange portion of the first member. But Above Of the first member Flange part Between the end faces of the flange portions in contact with each other Whereas The laser head is oriented parallel to the flange surface of each flange portion. Predetermined positional relationship In addition, A first support member that supports the laser head; a second guide portion that is supported so as to be relatively movable with respect to the first support member; and abuts against a main body portion of the second member; and the second member And a second support disposed so as to face the first grip when the second grip is in contact with the flange of the second member. Members, Driving the second support member relative to the first support member on which the laser head is supported; In a state where the flange portions of the first and second members are sandwiched between the first grip portion and the second grip portion, Between each end face of each of the flange portions, While irradiating a laser beam from the laser head parallel to the flange surface of the flange portion, Each Drive means for driving the first and second support members relative to the first and second members along the flange portion is provided.
[0020]
Further, according to a fifth aspect of the present invention, the second support member is swingably supported with respect to the first support member, and the drive means includes the second gripping portion of the second member. The second support member may be driven so as to be urged with a predetermined pressure in the direction of the first gripping portion when abutting on the flange portion and to maintain the urged state.
[0021]
The drive means is configured to be mounted on a robot arm of a robot apparatus, for example, and supports the second support member in a swingable manner with respect to the first support member, for example, via a link mechanism. The link mechanism can be driven by a cylinder so as to sandwich the flange portions of the first and second members.
[0022]
Alternatively, as the laser welding apparatus of the present invention, as described in claim 6, the first member and the second member formed by a thin metal plate so that the main body portion and the flange portion are substantially orthogonal to each other, The first member and the second member are arranged so that each flange portion faces each other, and a laser beam is irradiated from the laser head in parallel to the flange surface of the flange portion between the end faces of each flange portion. In the laser welding apparatus for joining the first and second members, each of the first and second members has a guide portion parallel to the flange portion, and is substantially parallel to the main body portion of the first and second members. Third member and fourth member disposed so as to sandwich the flange portion of the second member, a first guided portion that contacts the guiding portion of the third member, and guidance of the fourth member A second guided portion that comes into contact with the portion, Predetermined position between the first the guided portion and the guided portion Between the end faces of the flange portions Whereas The laser head is oriented parallel to the flange surface of each flange portion. Predetermined positional relationship In addition, A support member for supporting the laser head, and the third member; Above The flange portions of the first and second members are sandwiched between the fourth member and the fourth member. In a state where each flange portion is between the end surfaces of each flange portion, While irradiating a laser beam from the laser head parallel to the flange surface of the flange portion, Each Drive means for driving the support member relative to the first to fourth members along the flange portion may be provided. For example, a V-shaped groove is formed on the outer surface of the third member and the fourth member to form the guiding portion, and a roller member having a V-shaped cross section that matches the V-shaped groove is used as the first guided portion. And it can be set as the 2nd guided part, and it can comprise so that this roller member may rotate along the said V-shaped groove.
[0023]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings. 1 to 9 relate to a laser welding apparatus according to an embodiment of the present invention and are used for welding a fuel tank. First, in FIG. 1 showing an enlarged welded portion on the outer periphery of the fuel tank, the upper shell 100 and the lower shell 200 of the two-part fuel tank constitute the first member and the second member of the present invention, respectively. Each of the upper shell 100 and the lower shell 200 is formed in a half container shape by a thin metal plate, for example, an aluminum-plated steel plate, and the main body portions 101 and 201 and the flange portions 102 and 202 are formed so as to be substantially orthogonal to each other. .
[0024]
When the upper shell 100 and the lower shell 200 are welded, the flange portions 102 and 202 are arranged to face each other. The laser unit 30 is arranged between the end faces 103 and 203 of the flange portions 102 and 202 so that the laser head 31 emits a laser beam in parallel to the flange surfaces of the flange portions 102 and 202. . The laser unit 30 is supported by the support arm 10 constituting the first support member of the present invention, and the laser head 31 is fixed to the support arm 10 so as to have a predetermined positional relationship (which will be described later). ing. The L-shaped swing arm 20 constituting the second support member of the present invention is supported so as to be swingable with respect to the support arm 10.
[0025]
Here, the configuration of the entire laser apparatus including the support arm 10, the swing arm 20, and the laser unit 30 will be described with reference to FIGS. As shown in FIG. 2, the support arm 10 is attached to the robot arm 50 via the floating mechanism 40. The robot arm 50 constitutes a part of a robot apparatus (not shown), and since it is well known, description thereof is omitted. The support arm 10 has an arm main body 10b fixed to the floating mechanism 40 and an L-shaped finger portion 10a joined to the tip thereof, and brackets 10c and 10d are supported vertically thereto. The laser unit 30 is fixed to the bracket 10c and supported in parallel with the arm body 10b, and the laser head 31 is held in the positional relationship shown in FIG. 2 with respect to the finger portion 10a. The swing arm 20 is swingably supported by the bracket 10d.
[0026]
The swing arm 20 is formed into a crank shape by joining an L-shaped finger portion 20a and an L-shaped arm main body 20b, and the arm main body 20b is rotatable around an axis C1 at its corners. It is pivotally supported by the bracket 10d. Further, one end of the drive arm 20c is pivotally supported at the tip of the arm body 20b so as to be rotatable about the axis C2. The other end of the drive arm 20c is connected to a pneumatic cylinder 61 of the drive unit 60, and is configured to be movable in the horizontal direction in FIG. In place of the pneumatic cylinder 61, a hydraulic cylinder or an electric motor may be used. Thus, in this embodiment, the arm main body 20b and the drive arm 20c constitute a swing link mechanism, and the arm main body 20b swings about the axis C1 in accordance with the movement of the drive arm 20c by the pneumatic cylinder 61. And the front-end | tip of the finger part 20a is comprised so that it may adjoin or space apart with respect to the front-end | tip of the finger part 10a.
[0027]
Next, returning to FIG. 1, the roller member 11 constituting the first gripping portion of the present invention is rotatably supported at the tip of the finger portion 10 a of the support arm 10, and the corner of the finger portion 10 a of the support arm 10 is supported. The ball unit 12 constituting the first guide portion of the present invention is mounted on the portion. Similarly, the roller member 21 constituting the second gripping portion of the present invention is rotatably supported at the tip of the finger portion 20a of the swing arm 20, and the second guide portion of the present invention is supported at the corner portion. A ball unit 22 is mounted.
[0028]
As shown in FIG. 1, the roller members 11 and 21 have rollers 11a and 21a rotatably supported on shafts 11c and 21c via bearings 11b and 21b, respectively. The shafts 11c and 21c are provided on the finger portions 10a and 20a. It is fixed to the tip. These roller members 11 and 21 are arranged so as to abut against the flange portions 102 and 202 and to face each other during welding operation.
[0029]
On the other hand, the ball units 12 and 22 are configured as shown in FIGS. 5 to 7, and are detachably supported by the finger portion 10a and the finger portion 20a. That is, the ball 12a is accommodated in the base 12b and is rotatably supported in a state protruding outward by a predetermined distance, and the base 12b is fitted into the recess formed in the finger portion 10a and fixed by the bolt B. Yes. Accordingly, by appropriately setting the thickness of the base 12b (dimension in the left-right direction in FIG. 5), or preparing bases of various thicknesses and selecting them appropriately, the finger portion 10a of the ball 12a The protruding distance can be set as appropriate. Thereby, the position held by the roller members 11 and 21 can be appropriately adjusted according to the width of the flange portions 102 and 202.
[0030]
The ball units 12 and 22 are arranged so as to contact the outer surfaces of the main body portions 101 and 201, respectively, during welding operation. Since the ball 12a smoothly moves on the outer surface of the main body 101 of the upper shell 100, the finger 10a (and eventually the roller member 11) moves smoothly while maintaining a predetermined gap with respect to the main body 101. Can be made. Accordingly, the roller 11a of the roller member 11 contacts the flange portion 102 at a position spaced apart from the main body portion 101 by a predetermined distance, and the distance from the contact position to the end surface 103 of the flange portion 102 is the width of the flange portion 102 during molding. Can be maintained substantially constant. For example, even in the present embodiment for a fuel tank having a circumference of 1 m or more, it can be kept constant in the range of 5 to 20 mm. Since the ball unit 22 has the same configuration, the description is omitted.
[0031]
Thus, when the upper shell 100 and the lower shell 200 are welded together by the laser welding apparatus having the above-described configuration, first, as shown in FIG. Deploy. At this time, the drive arm 20c of the laser welding apparatus is held at the initial position on the left side in FIG. 8, and the roller member 21 attached to the tip of the swing arm 20 is a roller attached to the tip of the support arm 10. It is in a state of being held at a position farthest from the member 11.
[0032]
When the robot arm 50 is driven and the support arm 10 is arranged so that the ball 12a of the ball unit 12 contacts the outer surface of the main body 101 and the roller 11a of the roller member 11 contacts the flange 102, the flange The positional relationship in FIG. 8 is such that the laser head 31 is directed parallel to the flange surface between the end faces 103 and 203 of the portions 102 and 202. In this state, when the pneumatic cylinder 61 is driven rightward in FIG. 8 and the drive arm 20c is driven in the same direction, the swing arm 20 swings clockwise around the axis C1. Therefore, as shown in FIG. 9, the swing arm 20 is driven until the roller member 21 comes into contact with the flange portion 202 and maintained in a state of being urged with a predetermined pressure. At this time, since the roller member 21 is located at a position facing the roller member 11, the flange portions 102 and 202 are sandwiched at a predetermined pressure by both. As a result, the portion between the contact positions of the roller members 11 and 21 shown in FIG. Is formed.
[0033]
Thus, a laser beam is irradiated from the laser head 31 in parallel to the flange surfaces of the flange portions 102 and 202 between the end surfaces 103 and 203 in a state where the flange portions 102 and 202 are sandwiched by the roller members 11 and 21. On the other hand, by moving along the flange portions 102 and 202, it is possible to continuously weld even a three-dimensional weld target. During this time, the roller members 11 and 21 move while rolling on the flange surface, and the balls 12a and 22a move smoothly while maintaining a predetermined gap with respect to the main body portions 101 and 201. While maintaining a predetermined positional relationship between the end faces 103 and 203, welding can be appropriately performed while moving at a relatively high speed (for example, 3 m / min or more). In addition, since the steam generated at the time of welding is released from the minute gap between the end faces 103 and 203, a stable joint state can be ensured. If necessary, the minute gap between the end faces 103 and 203 can be made substantially zero.
[0034]
Next, a laser welding apparatus according to another embodiment of the present invention will be described with reference to FIGS. In the present embodiment, the presser molds 300 and 400 are arranged so as to surround the upper shell 100 and the lower shell 200 with a predetermined gap therebetween, and these constitute the third member and the fourth member of the present invention. ing. In these presser molds 300 and 400, the opening end portions 302 and 402 are formed in the same cross-sectional shape as the tip portions of the rollers 11a and 11b described above, and the flange portions 102 and 202 are formed by these opening end portions 302 and 402. Is held at a predetermined pressure. Furthermore, V-shaped grooves 301 and 401 are formed on the outer surfaces of the presser molds 300 and 400 as a guide portion of the present invention in parallel with a predetermined distance from the flange portions 102 and 202. These V-shaped grooves 301 and 401 are desirably formed with an accuracy of 3/100 to 10/100 mm of the weld surface.
[0035]
A support arm 70 is fixed to the floating mechanism 40 in place of the support arm 10 described above, and a support arm 80 is provided in place of the swing arm 20 and is fixed to the floating mechanism 40. That is, in this embodiment, as shown in FIG. 11, the support arms 70 and 80 are symmetrical, and both are fixed to the floating mechanism 40, and these constitute a support member. Therefore, the drive unit 60 described above is not provided. In the present embodiment, the roller members 11 and 21 and the ball units 12 and 22 are not provided, and the roller members 71 and 81 having V-shaped cross sections that match the V-shaped grooves 301 and 401 shown in FIG. Is rotatably supported by the support arms 70 and 80.
[0036]
That is, as shown in FIG. 10, on the support portions 70a and 80a of the support arms 70 and 80, roller members 71 and 81 constituting the first and second guided portions of the present invention are rotatably supported, respectively. ing. The roller members 71 and 81 have rollers 71a and 81a each having a V-shaped cross section supported rotatably on shafts 71c and 81c via bearings 71b and 81b, respectively. It is fixed to. These roller members 71 and 81 are arranged so that the rollers 71 a and 81 a are fitted in the V-shaped grooves 301 and 401. Therefore, the laser head 31 is disposed between the V-shaped groove 301 and the V-shaped groove 401, and the tip is parallel to the flange surface with respect to a predetermined positional relationship, that is, between the end surfaces 103 and 203 of the flange portions 102 and 202. Hold to be oriented. 10 to 13, members substantially the same as those described in FIGS. 1 to 4 are denoted by the same reference numerals (70 b and 80 b are arm bodies).
[0037]
Thus, when the upper shell 100 and the lower shell 200 are welded together by the laser welding apparatus having the configuration shown in FIGS. 10 to 13, first, as shown in FIG. 10, the upper shell 100 and the flange portions 102 of the lower shell 200 It arrange | positions so that 202 may oppose. The presser molds 300 and 400 are arranged so as to surround the upper shell 100 and the lower shell 200 with a predetermined gap therebetween, and the flange portions 102 and 202 are sandwiched by the opening end portions 302 and 402 with a predetermined pressure. As a result, the portion between the contact positions of the opening end portions 302 and 402 shown in FIG. A gap is formed.
[0038]
When the robot arm 50 is driven in this state and the support arms 70 and 80 are arranged so that the roller members 71 and 81 are fitted in the V-shaped grooves 301 and 401 of the presser molds 300 and 400, the laser head 31 has a flange portion. The end surfaces 103 and 203 of the 102 and 202 are oriented parallel to the flange surface. Thus, the roller members 71 and 81 are guided into the V-shaped grooves 301 and 401, and smoothly maintain a predetermined gap with respect to the presser molds 300 and 400, and consequently the main body portions 101 and 201 of the upper shell 100 and the lower shell 200. Moving.
[0039]
Thus, the laser head 31 can be continuously welded by moving along the flange portions 102 and 202 while irradiating the laser beam parallel to the flange surfaces of the flange portions 102 and 202. During this time, the laser head 31 can be appropriately welded while being moved in a state where the laser head 31 is maintained in a predetermined positional relationship with the end faces 103 and 203. In addition, since the steam generated during the welding is released from the gap between the end faces 103 and 203, a stable joining state can be ensured. In any of the above-described embodiments, the upper shell 100 and the lower shell 200 are fixed and the laser unit 30 side is driven. However, the fixed side and the driving side may be reversed. Good.
[0040]
【The invention's effect】
Since this invention is comprised as mentioned above, there exists an effect as described below. That is, in the laser welding method and apparatus according to claims 1 and 4, Driving the second support member relative to the first support member on which the laser head is supported; The first guide portion and the second guide portion are brought into contact with the main body portions of the first and second members, and the flange portions of the first and second members are sandwiched between the first grip portion and the second grip portion. In the state Between the end faces of each flange, Since the first and second support members are driven relative to the first and second members along the flange portion while irradiating the laser beam from the laser head parallel to the flange surface, It can be welded continuously even for 3D-shaped welding objects , Between the flange end faces The laser head is oriented parallel to the flange surface. While maintaining the predetermined positional relationship, it is possible to weld smoothly and appropriately while moving along the flange portion.
[0041]
In the laser welding method and apparatus, when configured as described in claims 2 and 5, steam generated during welding is discharged from a minute gap between the end faces of the flange portion, so that a stable joint state can be secured. it can. Note that the minute gap between the end faces of the flange portion can be made substantially zero.
[0042]
In the laser welding method and apparatus according to claims 3 and 6, the laser welding method and apparatus are arranged so as to be substantially parallel to the main body portions of the first and second members and sandwich the flange portions of the first and second members. Third member and fourth member And the first and second guided parts that abut against these guiding parts, the laser head is arranged at a predetermined position between them, and the flange surface between the end faces of each flange part. A support member for supporting the laser head in a predetermined positional relationship in which the laser head is directed in parallel; With , The flange portions of the first and second members are sandwiched between the third member and the fourth member. Between the end faces of each flange Since the support member is driven relative to the first to fourth members along the flange portion while irradiating the laser beam from the laser head parallel to the flange surface. , Between the flange end faces The laser head is oriented parallel to the flange surface. While maintaining the predetermined positional relationship, it is possible to weld smoothly and appropriately while moving along the flange portion.
[Brief description of the drawings]
FIG. 1 is a partial cross-sectional view showing an enlarged welded portion on the outer periphery of a fuel tank in a laser welding apparatus according to an embodiment of the present invention.
FIG. 2 is a front view of a laser welding apparatus according to an embodiment of the present invention.
FIG. 3 is a side view of a laser welding apparatus according to an embodiment of the present invention.
FIG. 4 is a bottom view of a laser welding apparatus according to an embodiment of the present invention.
FIG. 5 is a cross-sectional view showing an example of a ball unit used in a laser welding apparatus according to an embodiment of the present invention.
FIG. 6 is a plan view showing an example of a ball unit used in the laser welding apparatus according to an embodiment of the present invention.
FIG. 7 is a side view showing an example of a ball unit used in a laser welding apparatus according to an embodiment of the present invention.
FIG. 8 is a front view showing a state before the welding operation of the laser welding apparatus according to the embodiment of the present invention.
FIG. 9 is a front view showing a welding operation state of the laser welding apparatus according to one embodiment of the present invention.
FIG. 10 is an enlarged partial cross-sectional view of a welded portion on the outer periphery of a fuel tank in a laser welding apparatus according to another embodiment of the present invention.
FIG. 11 is a front view of a laser welding apparatus according to another embodiment of the present invention.
FIG. 12 is a side view of a laser welding apparatus according to another embodiment of the present invention.
FIG. 13 is a bottom view of a laser welding apparatus according to another embodiment of the present invention.
[Explanation of symbols]
10 support arms, 20 swinging arms, 11, 21 roller members,
12, 22 ball unit, 30 laser unit,
31 laser head, 40 floating mechanism,
50 robot arm, 60 drive unit, 61 pneumatic cylinder,
71, 81 roller member, 100 upper shell, 200 lower shell,
101, 201 body part, 102, 202 flange part,
300, 400 Presser type, 301, 401 V-shaped groove

Claims

The first member and the second member, which are each formed of a thin metal plate so that the main body portion and the flange portion are substantially orthogonal to each other, are disposed so that the respective flange portions face each other, and between the end surfaces of the respective flange portions. On the other hand, in the laser welding method of joining the first member and the second member by irradiating a laser beam in parallel to the flange surface of the flange portion from the laser head, the first contact with the main body portion of the first member is performed. 1 guide portion, and having a first gripping portion abutting against the flange portion of said first member, said first gripping portion of the flange portion of said each in contact with the flange portion of said first member A first support member that supports the laser head and a relative position relative to the first support member in a predetermined positional relationship in which the laser head is directed parallel to the flange surface of each flange portion with respect to the end surfaces . Movably supported A second guide portion that contacts the main body portion of the second member; and a second grip portion that contacts the flange portion of the second member, and the second grip portion is a flange portion of the second member. And a second support member disposed so as to face the first grip portion when contacting the first support member, and the second support member is disposed on the first support member on which the laser head is supported. The flanges of the first and second members are driven and sandwiched between the end faces of the flange portions with the flange portions of the first and second members sandwiched between the first grip portion and the second grip portion. The first and second support members are driven relative to the first and second members along the respective flange portions while irradiating a laser beam from the laser head in parallel with the flange surface of each portion. And a laser welding method.

When the second gripping portion comes into contact with the flange portion of the second member, the second gripping portion is biased with a predetermined pressure in the direction of the first gripping portion and the biased state is maintained. The laser welding method according to claim 1, wherein a support member is supported by the first support member.

The first member and the second member, which are each formed of a thin metal plate so that the main body portion and the flange portion are substantially orthogonal to each other, are disposed so that the respective flange portions face each other, and between the end surfaces of the respective flange portions. On the other hand, in the laser welding method of joining the first member and the second member by irradiating a laser beam from the laser head in parallel to the flange surface of the flange portion, the flange portions of the first and second members, respectively. And a third member disposed so as to sandwich the flange portions of the first and second members and substantially parallel to the main body portions of the first and second members. 4 member, a first guided portion that contacts the guiding portion of the third member, and a second guided portion that contacts the guiding portion of the fourth member, and the second guided portion It said laser head to a predetermined position between the first the guided portion While location, to between the end faces of the flange portion of the respective, in a predetermined positional relationship to be oriented parallel to the laser head on the flange surface of the flange portion of the respective, and a supporting member supporting the laser head, while holding the flange portion of the first and second members between the fourth member and the third member, to between the end faces of the flange portion of said each flange portion of the respective A laser welding method, wherein the support member is driven relative to the first to fourth members along each flange portion while irradiating a laser beam from the laser head in parallel with the flange surface. .

The first member and the second member, which are each formed of a thin metal plate so that the main body portion and the flange portion are substantially orthogonal to each other, are disposed so that the respective flange portions face each other, and between the end surfaces of the respective flange portions. On the other hand, in a laser welding apparatus that joins the first member and the second member by irradiating a laser beam in parallel to the flange surface of the flange portion from the laser head, the first portion that contacts the main body portion of the first member. 1 guide portion, and having a first gripping portion abutting against the flange portion of said first member, said first gripping portion of the flange portion of said each in contact with the flange portion of said first member A first support member that supports the laser head and a relative position relative to the first support member in a predetermined positional relationship in which the laser head is directed parallel to the flange surface of each flange portion with respect to the end surfaces . Movably supported A second guide portion that contacts the main body portion of the second member; and a second grip portion that contacts the flange portion of the second member, and the second grip portion is a flange portion of the second member. A second support member disposed so as to be opposed to the first gripping portion when being in contact with the first support member, and driving the second support member relative to the first support member on which the laser head is supported. In a state where the flange portions of the first and second members are sandwiched between the first grip portion and the second grip portion, the flange portions of the flange portions are disposed between the end surfaces of the flange portions. Driving means for driving the first and second support members relative to the first and second members along each flange portion while irradiating a laser beam from the laser head parallel to the flange surface A laser welding apparatus comprising:

The second support member is swingably supported with respect to the first support member, and the driving means is configured to move the first support member when the second gripping portion comes into contact with the flange portion of the second member. 5. The laser welding apparatus according to claim 4, wherein the second support member is driven so as to be biased at a predetermined pressure in the direction of the grip portion and to maintain the biased state.

The first member and the second member, which are each formed of a thin metal plate so that the main body portion and the flange portion are substantially orthogonal to each other, are disposed so that the respective flange portions face each other, and between the end surfaces of the respective flange portions. On the other hand, in the laser welding apparatus that joins the first member and the second member by irradiating a laser beam in parallel to the flange surface of the flange portion from the laser head, the flange portions of the first and second members, respectively. And a third member disposed so as to sandwich the flange portions of the first and second members and substantially parallel to the main body portions of the first and second members. 4 member, a first guided portion that contacts the guiding portion of the third member, and a second guided portion that contacts the guiding portion of the fourth member, and the second guided portion It said laser head to a predetermined position between the first the guided portion While location, to between the end faces of the flange portion of the respective, in a predetermined positional relationship directing said laser head in parallel to the flange surface of the flange portion of the respective, a support member for supporting the laser head, said first while holding the flange portion of the first and second members between the third member and the fourth member, to between the end faces of the flange portion of said each flange surface of the flange portion of the respective Drive means for driving the support member relative to the first to fourth members along the flange portions while irradiating a laser beam from the laser head in parallel with the laser head. Laser welding equipment.