JP4479065B2

JP4479065B2 - Laser processing equipment

Info

Publication number: JP4479065B2
Application number: JP2000188041A
Authority: JP
Inventors: 昭浩西見; 誠二福冨; 文夫松坂; 寿夫中村
Original assignee: IHI Corp
Current assignee: IHI Corp
Priority date: 2000-06-22
Filing date: 2000-06-22
Publication date: 2010-06-09
Anticipated expiration: 2020-06-22
Also published as: JP2002001555A

Description

【０００１】
【発明の属する技術分野】
本発明はレーザ加工装置に関するものである。
【０００２】
【従来の技術】
近年、物品の切断、溶接等の加工にはレーザ光が使用されるようになっており、このため、従来から種々のレーザ加工装置が提案されている。而して、レーザ加工装置では、物品の加工が支障なく行われているか否か、又、装置が正常に作動しているか否か監視する必要がある。
【０００３】
被加工物の加工状態若しくは装置の作動状態を監視し得るようにした従来の加工装置の一例としては、例えば、特開平１０−２０２３７８号公報に示すような装置がある。而して、この装置では、被加工物からの光を監視用光学系であるレンズに透過させ、透過した光を監視用のレーザ光を伝送するために設けた光ファイバに伝送し、干渉フィルタ及びモニタ用光学系であるレンズを透過させた後、フォトダイオードにより検出し、その結果から被加工物の加工状態が正常か否か或は装置が正常に作動しているか否か、監視している。
【０００４】
【発明が解決しようとする課題】
上述のレーザ加工装置では、レーザ光を被加工物へ伝送するための入射光学系や出射光学系のレンズ、入射光学系から伝送されて来たレーザ光を出射光学系へ伝送するための光ファイバの他に、加工状態を監視するために、監視光学系のレンズ、監視用の光を伝送するための光ファイバ等が必要になる。従って、斯かる装置では構造が複雑となると共に、レーザ光を出射光学系へ伝送するための光ファイバを透過して来た光を間接的にモニタリングしているため、監視の信頼性が低い、等の問題がある。
【０００５】
本発明は、上述の実情に鑑み、被加工物から反射して来た反射光を直接検出するようにして、被加工物の加工状態或は装置の状態を監視するための機構をシンプルにすると共に、被加工物の加工状態或は装置の状態を容易且つ確実に監視し得るようにしたレーザ加工装置を提供することを目的としてなしたものである。
【０００６】
【課題を解決するための手段】
本発明の請求項１のレーザ加工装置は、レーザ発振器と、該レーザ発振器から発振されたレーザ光を反射させる折返しミラーと、該折返しミラーで反射されたレーザ光を入射集光レンズを経て伝送する光ファイバと、該光ファイバで伝送された該レーザ光を集光レンズにより集光して被加工物に照射し該被加工物を加工する加工ヘッドとを備え、
該レーザ発振器より該被加工物に照射された該レーザ光を該被加工物で反射して反射光にするレーザ加工装置であって、
該折返しミラーの背面に設置され且つ該折返しミラーを透過した該反射光の光強度を検出する光検出器と、
該光検出器で検出した光強度の検出信号と予め設定した光強度の閾値とを比較して被加工物の加工状態若しくは装置の作動状態が正常か否かを判別する手段と、
該加工ヘッドに備えられた該集光レンズの焦点位置を検出するように、該被加工物の上面で回転して該レーザ光を横切る治具を配置し且つ該レーザ発振器から該被加工物へ照射される該レーザ光を該治具で反射して反射光にする焦点位置検出器と、
該焦点位置検出器で反射した該反射光から該被加工物の加工点に対する該集光レンズの焦点のずれを求め、該加工ヘッドを該被加工物に近接、離反するよう移動させる手段に、前記焦点が該被加工物の加工点に合うよう該加工ヘッドを移動させる指令を与える手段と、
該折返しミラーを透過した該反射光を検出する該光検出器を、検出面が４分割された光検出器とし、該光検出器で検出した複数の光強度の検出信号から、該集光レンズの焦点の該被加工物における加工点平面方向のずれを求め、該ずれをなくすよう、該被加工物を支持する手段を該被加工物の平面方向へ移動させる手段に指令を与える手段と、
を備えたものである。
【０００７】
本発明の請求項２のレーザ加工装置は、レーザ発振器と、該レーザ発振器から発振されたレーザ光を反射させる第一の折返しミラーと、該第一の折返しミラーで反射された該レーザ光を反射させる第二の折返しミラーと、該第二の折返しミラーで反射された該レーザ光を入射集光レンズを経て伝送する光ファイバと、該光ファイバで伝送された該レーザ光を集光レンズにより集光して被加工物に照射し該被加工物を加工する加工ヘッドとを備え、
該レーザ発振器より該被加工物に照射された該レーザ光を該被加工物で反射して反射光にするレーザ加工装置であって、
該第一若しくは第二の折返しミラーの背面に設置され且つ該第一若しくは第二の折返しミラーを透過した該反射光の光強度を検出するための第一の光検出器と、
該第二若しくは第一の折返しミラーの背面に設置され且つ該レーザ発振器から発振されて該第二若しくは第一の折返しミラーを透過した該レーザ光の光強度を検出するための第二の光検出器と、
該第一、第二の光検出器で検出した光強度の検出信号を比較すると共に比較して求めた信号を予め設定した光強度の閾値と比較して被加工物の加工状態若しくは装置の作動状態が正常か否かを判別する手段と、
該加工ヘッドに備えられた該集光レンズの焦点位置を検出するように、該被加工物の上面で回転して該レーザ光を横切る治具を配置し且つ該レーザ発振器から該被加工物へ照射される該レーザ光を該治具で反射して反射光にする焦点位置検出器と、
該焦点位置検出器で反射した該反射光から該被加工物の加工点に対する該集光レンズの焦点のずれを求め、該加工ヘッドを該被加工物に近接、離反するよう移動させる手段に、前記焦点が該被加工物の加工点に合うよう該加工ヘッドを移動させる指令を与える手段と、
該第二の折返しミラーを透過した該反射光を検出する該第二の光検出器を、検出面が４分割された光検出器とし、該光検出器で検出した複数の光強度の検出信号から、該集光レンズの焦点の該被加工物における加工点平面方向のずれを求め、該ずれをなくすよう、該被加工物を支持する手段を該被加工物の平面方向へ移動させる手段に指令を与える手段と、
を備えたものである。
【０００８】
本発明の請求項３のレーザ加工装置は、レーザ発振器と、該レーザ発振器から発振されたレーザ光を反射させる折返しミラーと、該折返しミラーで反射された該レーザ光を入射集光レンズを経て伝送する光ファイバと、該光ファイバで伝送された該レーザ光を集光レンズにより集光して被加工物に照射し該被加工物を加工する加工ヘッドとを備え、
該レーザ発振器より該被加工物に照射された該レーザ光を該被加工物で反射して反射光にするレーザ加工装置であって、
該折返しミラーの背面に設置され且つ折返しミラーを透過した該反射光の光強度を検出するための第一の光検出器及び該折返しミラーを透過した該レーザ光の光強度を検出するための第二の光検出器と、
該第一、第二の光検出器で検出した光強度の検出信号を比較すると共に比較して求めた信号を予め設定した光強度の閾値と比較して被加工物の加工状態若しくは装置の作動状態が正常か否かを判別する手段と、
該加工ヘッドに備えられた該集光レンズの焦点位置を検出するように、該被加工物の上面で回転して該レーザ光を横切る治具を配置し且つ該レーザ発振器から該被加工物へ照射される該レーザ光を該治具で反射して反射光にする焦点位置検出器と、
該焦点位置検出器で反射した該反射光から該被加工物の加工点に対する該集光レンズの焦点のずれを求め、該加工ヘッドを該被加工物に近接、離反するよう移動させる手段に、前記焦点が該被加工物の加工点に合うよう該加工ヘッドを移動させる指令を与える手段と、
該折返しミラーを透過した該反射光を検出する該第二の光検出器を、検出面が４分割された光検出器とし、該光検出器で検出した複数の光強度の検出信号から、該集光レンズの焦点の該被加工物における加工点平面方向のずれを求め、該ずれをなくすよう、該被加工物を支持する手段を該被加工物の平面方向へ移動させる手段に指令を与える手段と、
を備えたものである。
【００１１】
本発明の請求項４のレーザ加工装置は、該レーザ発振器から発振されて該折返しミラー側へ伝送される該レーザ光を遮断するシャッタと、該シャッタで遮断された該レーザ光を吸収するビームダンパと、該シャッタを駆動するインタロック装置と、装置の作動状態が異常な場合には、該インタロック装置に該シャッタを閉止させる指令を与える手段を設けたものである。
【００１２】
本発明によれば、被加工物の加工状態若しくは装置の作動状態を監視するための機構がシンプルとなって、設備費、運転維持費を抑えることが可能となり、又、被加工物から反射して来た反射光を直接検出するようにしているため、容易且つ確実に被加工物の加工状態若しくは装置の状態を監視することができ、更には、装置の保護を確実に行うことができ、更に又、被加工物の加工を最適な状態で行うことができる。
【００１３】
【発明の実施の形態】
以下、本発明の実施の形態を図示例と共に説明する。
【００１４】
図１及び図２は本発明のレーザ加工装置を実施する形態の一例である。図１中、１はレーザ発振器、２はレーザ発振器１からの加工用のレーザ光３の伝送方向を変えるための折返しミラー、４は折返しミラー２で向きを変えて伝送されて来たレーザ光３の伝送方向を変えるための折返しミラー、５は折返しミラー４で向きを変えて伝送されて来たレーザ光３を集光するための入射集光レンズである。
【００１５】
６は入射集光レンズ５からのレーザ光３を伝送するための光ファイバ、７は光ファイバ６から伝送されたレーザ光３を被加工物８に照射する集光レンズ９を備えた加工ヘッドである。而して、加工ヘッド７はサーボモータ等の駆動装置１０を駆動することにより、送りネジ軸１１及びナット１２を介して昇降し得るようになっており、昇降することにより、集光レンズ９の焦点を被加工物８の加工点Ｐに合せ得るようになっている。
【００１６】
１３は折返しミラー２で反射せずに透過したレーザ光３の光強度を検出し、検出信号Ｖ１として監視制御装置１４へ送信するフォトセンサ等の光検出器、１５は被加工物８で反射して戻って来ると共に折返しミラー４を透過した反射光１６の光強度を検出し、検出信号Ｖ２として監視制御装置１４へ送信するフォトセンサ等の光検出器である。
【００１７】
１７は光ファイバ６等の伝送光学系に何等かの異常が発生した場合にインタロック装置１８により切替えられ、レーザ発振器１から発振されて折返しミラー２へ伝送されるレーザ光３を遮断するためのシャッタ、１９はシャッタ１７からのレーザ光３を吸収するためのビームダンパであり、監視制御装置１４からは、駆動装置１０及びインタロック装置１８へ夫々指令信号Ｖ３，Ｖ４を与え得るようになっている。
【００１８】
２０は被加工物８の加工点Ｐに集光レンズ９の焦点があるか否かを検出するための焦点位置検出器であり、焦点位置検出器２０は駆動装置２１により水平方向へ回転し、集光レンズ９で集光されたレーザ光３を反射させるための、高反射材料から成る板状の冶具２２を備えている。
【００１９】
２３は反射光１６の光強度が予め設定した閾値を越えたら、監視制御装置１４からの指令により警報を発する警報器である。
【００２０】
次に、上記図示例の作動を説明する。
【００２１】
被加工物８を加工する際には、シャッタ１７は開いて図１の実線位置にあり、加工ヘッド７は集光レンズ９の焦点が被加工物８の加工点Ｐに位置するよう高さが調整してあり、焦点位置検出器２０の冶具２２は駆動装置に２１により水平方向へ回転している。
【００２２】
レーザ発振器１から発振されたレーザ光３は、折返しミラー２，４で反射して伝送方向を変えられ、折返しミラー４から入射集光レンズ５へ導入されたうえ、集光されて光ファイバ６へ入射され、光ファイバ６の先端から出射されて集光レンズ９により集光され、被加工物８の加工点Ｐに照射されて被加工物８が加工される。加工としては、溶接や切断がある。
【００２３】
上述の作業の際、レーザ発振器１からのレーザ光３の一部は折返しミラー２を透過して光検出器１３により検出され、検出信号Ｖ１として監視制御装置１４へ与えられる。又、被加工物８の表面から反射した反射光１６は集光レンズ９及び光ファイバ６並びに入射集光レンズ５を経て折返しミラー４ヘ達し、折返しミラー２へ向けて反射するが、一部の反射光１６は折返しミラー４を透過して光検出器１５により検出され、検出信号Ｖ２として監視制御装置１４ヘ与えられる。
【００２４】
監視制御装置１４では、光検出器１５からの光強度の検出信号Ｖ２を基として加工状態或は装置の状態が監視され、判別される。すなわち、例えば検出信号Ｖ２が予め監視制御装置１４に設定した光強度の閾値よりも低い場合には、被加工物８の加工状態は正常であり、且つレーザ加工装置に異常は発生しておらず、このため、被加工物８の加工は継続される。この場合、光検出器１３からの検出信号Ｖ１と光検出器１５からの検出信号Ｖ２を比較して差を求め、その差から状態を判別すると、被加工物８の加工が正常に行なわれているか否か、或は、レーザ加工装置に異常が生じているか否かをより正確に監視することができ、レーザ光３がパルス光の場合にも対応することができる。
【００２５】
焦点位置検出器２０の水平回転する冶具２２は高反射材料が用いられているため、冶具２２が被加工物８の上面でレーザ光３を横切った場合には、反射光１６の光強度は高くなる。このため、光検出器１５からの検出信号Ｖ２の値を基に、予め監視制御装置１４では、集光レンズ９の焦点が被加工物８の加工点Ｐにあるかどうか、又どの程度ずれているかが判別される。
【００２６】
而して、集光レンズ９の焦点が被加工物８の加工点Ｐにない場合には、予め監視制御装置１４から駆動装置１０に指令信号Ｖ３が与えられ、駆動装置１０が駆動される。このため、送りネジ軸１１が回転して加工ヘッド７延いては集光レンズ９が昇降して、その焦点は被加工物８の加工点Ｐに一致し、自動焦点位置補正が行なわれる。
【００２７】
光検出器１５からの検出信号Ｖ２又は、光検出器１３からの検出信号Ｖ１と光検出器１５からの検出信号Ｖ２を比較したものが、閾値よりも高い場合には、予め監視制御装置１４から警報器２３へ指令が与えられて警報器２３が被加工物８の加工状態やレーザ加工装置の異常を知らせると共に監視制御装置１４からインタロック装置１８へ指令信号Ｖ４が与えられてシャッタ１７が閉じるため、レーザ発振器１から発振されたレーザ光３はシャッタ１７により遮断されてビームダンパ１９に吸収される。従って、被加工物８の加工が中止されると共に、レーザ加工装置が熱により損傷することを防止することができる。
【００２８】
本図示例によれば、被加工物８の加工状態若しくは装置の作動状態を監視するための機構がシンプルであるため、設備費、運転維持費を抑えることが可能となり、又、被加工物８から反射して来た反射光１６を直接検出するようにしているため、容易且つ確実に被加工物８の加工状態若しくは装置の状態を監視することができ、更には、装置の保護を確実に行うことができ、更に又、被加工物８の加工を最適な状態で行うことができる。
【００２９】
図３及び図４は本発明のレーザ加工装置を実施する形態の他の例であり、レーザ加工装置は基本的には、図１、２に示すものと共通の構成物品を備えている。図３中、１５’は被加工物８で反射して戻って来て折返しミラー４を透過した反射光の光強度を検出し得るようにした、フォトセンサ等の光検出器である。この光検出器１５’は図４に示すように検出面が４分割されており、４個の検出信号Ｖ２１，Ｖ２２，Ｖ２３，Ｖ２４を監視制御装置１４へ与え得るようになっている。
【００３０】
２４は被加工物８を支持するベッドで、ベッド２４は、サーボモータ等の駆動装置２５により平面的に見て紙面に対し平行なＸ方向へ移動し得るようにした上段ベッド２６及びサーボモータ等の駆動装置２７により平面的に見て紙面に対し直交するＹ方向へ移動し得るようにした下段ベッド２８を備えている。
【００３１】
監視制御装置１４では、光検出器１５’からの検出信号Ｖ２１，Ｖ２２，Ｖ２３，Ｖ２４を基として、平面的に見て被加工物８のどの位置の加工を行っているか判別し得るようになっていると共に、監視制御装置１４からは、ベッド２４の駆動装置２５，２７に指令信号Ｖ５，Ｖ６を与えて駆動装置２５，２７を駆動し、上、下段ベッド２６，２８の加工面の平面的な位置を調整し、被加工物８の加工位置を補正し得るようになっている。
【００３２】
本図示例における被加工物８の加工の仕方は、基本的には、図１、２の図示例のものと略同じであるが、本図示例では、被加工物８の加工位置を補正する点で前記図示例と相違する。すなわち、本図示例では、被加工物８で反射して戻ってきた反射光１６の一部は折返しミラー４を透過して光検出器１５’により検出され、光強度の検出信号Ｖ２１，Ｖ２２，Ｖ２３，Ｖ２４として光検出器１５’から監視制御装置１４へ与えられる。
【００３３】
監視制御装置１４では、検出信号Ｖ２１，Ｖ２２，Ｖ２３，Ｖ２４が加算されてトータルの検出信号Ｖ１が求められ、予め設定してある光強度の閾値と比較されるか或は、光検出器１３からの光強度の検出信号Ｖ１と比較されたうえ、被加工物の加工状態若しくは装置の作動状態が判別され、監視される。
【００３４】
又、各検出信号Ｖ２１，Ｖ２２，Ｖ２３，Ｖ２４の電圧差により、集光レンズ９から被加工物８へ照射されるレーザ光３が、被加工物８の平面方向において、被加工物８の所定の加工点Ｐに照射されているか否か判別されると共に、集光レンズ９の焦点が加工点Ｐに対して被加工物８の平面方向にどの程度ずれているかが求められ、その結果に対応して、監視制御装置１４からは指令信号Ｖ５，Ｖ６が駆動装置２５，２７に与えられ、駆動装置２５，２７が駆動される。
【００３５】
従って、上段ベッド２６はＸ方向へ位置調整され、下段ベッド２８はＹ方向へ位置調整されるため、被加工物８は、平面方向において加工点Ｐが光レンズ９の焦点に合致するよう、Ｘ，Ｙ両方向へ位置調整される。
【００３６】
本発明の図示例においても、前述の図示例と同様、被加工物８の加工状態若しくは装置の作動状態を監視するための機構がシンプルとなって、設備費、運転維持費を抑えることが可能となり、又、被加工物８から反射して来た反射光１６を直接検出するようにしているため、容易且つ確実に被加工物８の加工状態若しくは装置の状態を監視することができ、更には、装置の保護を確実に行うことができ、更に又、被加工物８の加工を最適な状態で行うことができる。
【００３７】
なお、本発明の図示例では、２個の折返しミラーを設けて一方の折返しミラーの背面に設けた光検出器により、当該折返しミラーを透過したレーザ光の光強度を検出し、他方の折返しミラーの背面に設けた光検出器により、被加工物で反射して戻って来た反射光の光強度を検出する場合について説明したが、１個の折返しミラーの背面に９０度角度をずらして２個の光検出器を設け、一方の光検出器において、折返しミラーを透過して来たレーザ光の光強度を検出し、他方の光検出器において、被加工物で反射して戻って来て折返しミラーを透過した反射光の光強度を検出するようにしても実施できること、その他、本発明の要旨を逸脱しない範囲内で種々変更を加え得ることは勿論である。
【００３８】
【発明の効果】
本発明の請求項１〜６のレーザ加工装置によれば、被加工物の加工状態若しくは装置の作動状態を監視するための機構がシンプルとなって、設備費、運転維持費を抑えることが可能となり、又、被加工物から反射して来た反射光を直接検出するようにしているため、容易且つ確実に被加工物の加工状態若しくは装置の状態を監視することができ、更には、装置の保護を確実に行うことができ、更に又、被加工物の加工を最適な状態で行うことができる、等種々の優れた効果を奏し得る。
【図面の簡単な説明】
【図１】本発明の実施の形態の一例を示すレーザ加工装置の概要図である。
【図２】図１の装置に適用する焦点位置検出器の概略平面図である。
【図３】本発明の実施の形態の他の例を示すレーザ加工装置の概要図である。
【図４】図３の装置に適用する光検出器の正面図である。
【符号の説明】
１レーザ発振器
２折返しミラー
３レーザ光
４折返しミラー
５入射集光レンズ
６光ファイバ
７加工ヘッド
８被加工物
９集光レンズ
１０駆動装置（移動させる手段）
１３光検出器
１４監視制御装置（判別する手段、指令を与える手段）
１５光検出器
１５’ 光検出器
１６反射光
１７シャッタ
１８インタロック装置
１９ビームダンパ
２０焦点位置検出器
２１駆動装置（移動させる手段）
２５駆動装置（移動させる手段）
２６上段ベッド（支持する手段）
２７駆動装置（移動させる手段）
２８下段ベッド（支持する手段）
Ｐ加工点
Ｖ１検出信号
Ｖ２検出信号
Ｖ２１検出信号
Ｖ２２検出信号
Ｖ２３検出信号
Ｖ２４検出信号
Ｖ３指令信号（指令）
Ｖ４指令信号（指令）
Ｖ５指令信号（指令）
Ｖ６指令信号（指令）[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a laser processing apparatus.
[0002]
[Prior art]
In recent years, laser light has been used for processing such as cutting and welding of articles, and various laser processing apparatuses have been proposed in the past. Thus, in the laser processing apparatus, it is necessary to monitor whether or not the processing of the article is performed without any problem and whether or not the apparatus is operating normally.
[0003]
An example of a conventional processing apparatus that can monitor the processing state of the workpiece or the operation state of the apparatus is, for example, an apparatus as disclosed in JP-A-10-202378. Thus, in this apparatus, light from a workpiece is transmitted through a lens that is a monitoring optical system, and the transmitted light is transmitted to an optical fiber provided for transmitting a monitoring laser beam, and an interference filter. After passing through the lens that is the monitoring optical system, it is detected by a photodiode, and from the result, it is monitored whether the processing state of the workpiece is normal or whether the apparatus is operating normally. Yes.
[0004]
[Problems to be solved by the invention]
In the above-described laser processing apparatus, an incident optical system for transmitting laser light to a workpiece, a lens for an outgoing optical system, and an optical fiber for transmitting laser light transmitted from the incident optical system to the outgoing optical system. In addition, in order to monitor the processing state, a lens for a monitoring optical system, an optical fiber for transmitting monitoring light, and the like are required. Therefore, in such an apparatus, the structure is complicated, and since the light transmitted through the optical fiber for transmitting the laser light to the emission optical system is indirectly monitored, the monitoring reliability is low. There are problems such as.
[0005]
In view of the above circumstances, the present invention simplifies the mechanism for monitoring the processing state of the workpiece or the state of the apparatus by directly detecting the reflected light reflected from the workpiece. At the same time, it is an object of the present invention to provide a laser processing apparatus capable of easily and reliably monitoring the processing state of the workpiece or the state of the apparatus.
[0006]
[Means for Solving the Problems]
The laser processing apparatus according to claim 1 of the present invention, after the laser oscillator, and a folding mirror for reflecting the laser beam oscillated from the laser oscillator, the incident condenser lens of the laser beam reflected by the folding mirror Den comprising an optical fiber for transmission, and the laser light transmitted by the optical fiber is condensed by a condenser lens and irradiated to the workpiece machining head for machining the workpiece,
A laser processing apparatus configured to reflect the laser light irradiated on the workpiece from the laser oscillator to the reflected light by the workpiece;
A photodetector for detecting the light intensity of the reflected light transmitted through and the return mirror is placed on the back of the folding mirror,
Means for comparing the detection signal of the light intensity detected by the light detector with a preset light intensity threshold value to determine whether the processing state of the workpiece or the operation state of the apparatus is normal;
A jig that rotates on the upper surface of the workpiece and crosses the laser beam is disposed so as to detect the focal position of the condenser lens provided in the processing head, and from the laser oscillator to the workpiece. A focal position detector that reflects the irradiated laser beam with the jig to make reflected light; and
A means for obtaining a shift of the focal point of the condenser lens with respect to a processing point of the workpiece from the reflected light reflected by the focal position detector, and for moving the processing head so as to approach or separate from the workpiece. Means for giving a command to move the processing head so that the focal point is aligned with a processing point of the workpiece;
The light detector for detecting the reflected light transmitted through the folding mirror is a light detector having a detection surface divided into four, and the light collecting lens is obtained from detection signals of a plurality of light intensities detected by the light detector. A means for giving a command to a means for moving the means for supporting the workpiece in the plane direction of the workpiece so as to eliminate the deviation, and obtaining a deviation of the focal point of the workpiece in the plane direction of the machining point;
It is equipped with.
[0007]
The laser processing apparatus according to claim 2 of the present invention, reflective laser oscillator, a first folding mirror for reflecting the laser beam oscillated from the laser oscillator, the laser beam reflected by said first fold mirror a second folding mirror for, said second optical fiber to the laser beam reflected by the folding mirror through incident condenser lens feeding heat, a condenser lens to the laser light transmitted by the optical fiber is condensed by irradiating the workpiece and a machining head for machining the workpiece by,
A laser processing apparatus configured to reflect the laser light irradiated on the workpiece from the laser oscillator to the reflected light by the workpiece;
A first photodetector for detecting the light intensity of the reflected light transmitted through the and the first or second fold mirror attached to the back surface of the first or second fold mirror,
Second optical detection for detecting the light intensity of the laser beam is oscillated from installed and the laser oscillator is transmitted through the second or first fold mirror to the back of the second or first fold mirror And
Actuation of said first, second machining state or apparatus of the workpiece as compared to a threshold value of the light intensities preset signal obtained by comparing with comparing the detection signal of the light intensity detected by the photodetector Means for determining whether the state is normal;
A jig that rotates on the upper surface of the workpiece and crosses the laser beam is disposed so as to detect the focal position of the condenser lens provided in the processing head, and from the laser oscillator to the workpiece. A focal position detector that reflects the irradiated laser beam with the jig to make reflected light; and
A means for obtaining a shift of the focal point of the condenser lens with respect to a processing point of the workpiece from the reflected light reflected by the focal position detector, and for moving the processing head so as to approach or separate from the workpiece. Means for giving a command to move the processing head so that the focal point is aligned with a processing point of the workpiece;
The second photodetector for detecting the reflected light transmitted through the second folding mirror is a photodetector having a detection surface divided into four, and detection signals of a plurality of light intensities detected by the photodetector. To determine the deviation of the focal point of the condenser lens in the plane direction of the machining point in the workpiece, and to move the means for supporting the workpiece in the plane direction of the workpiece so as to eliminate the deviation. Means for giving a command;
It is equipped with.
[0008]
The laser processing apparatus according to claim 3 of the present invention, after the laser oscillator, and a folding mirror for reflecting the laser beam oscillated from the laser oscillator, the incident condenser lens the laser beam reflected by the folding mirror comprising an optical fiber for feeding heat, the laser light transmitted by the optical fiber is condensed by a condenser lens and irradiated to the workpiece and a machining head for machining the workpiece,
A laser processing apparatus configured to reflect the laser light irradiated on the workpiece from the laser oscillator to the reflected light by the workpiece;
The for detecting the light intensity of the first light detector and the laser beam transmitted through the folding mirror for detecting the transmitted light intensity of the reflected light and the return mirror is placed on the back of the folding mirror Two photodetectors,
Actuation of said first, second machining state or apparatus of the workpiece as compared to a threshold value of the light intensities preset signal obtained by comparing with comparing the detection signal of the light intensity detected by the photodetector Means for determining whether the state is normal;
A jig that rotates on the upper surface of the workpiece and crosses the laser beam is disposed so as to detect the focal position of the condenser lens provided in the processing head, and from the laser oscillator to the workpiece. A focal position detector that reflects the irradiated laser beam with the jig to make reflected light; and
A means for obtaining a shift of the focal point of the condenser lens with respect to a processing point of the workpiece from the reflected light reflected by the focal position detector, and for moving the processing head so as to approach or separate from the workpiece. Means for giving a command to move the processing head so that the focal point is aligned with a processing point of the workpiece;
The second photodetector for detecting the reflected light transmitted through the folding mirror is a photodetector having a detection surface divided into four, and from the detection signals of a plurality of light intensities detected by the photodetector, A deviation of the focal point of the condenser lens in the plane direction of the machining point in the workpiece is obtained, and a command is given to the means for moving the means for supporting the workpiece in the plane direction of the workpiece so as to eliminate the deviation. Means,
It is equipped with.
[0011]
The laser processing apparatus according to claim 4 of the present invention, a beam damper to absorb the shutter to block the laser light transmitted to said folding mirror side oscillated from the laser oscillator, the laser beam is interrupted by said shutter the interlock device for driving the shutter, when the operating state of the apparatus is abnormal, is provided with a means for giving a command to close the shutter to the interlock device.
[0012]
According to the present invention, the mechanism for monitoring the processing state of the workpiece or the operating state of the apparatus is simplified, and it is possible to suppress the equipment cost and the operation maintenance cost, and the reflection from the workpiece. Since the reflected light coming directly is detected, the processing state of the workpiece or the state of the apparatus can be monitored easily and reliably, and further, the apparatus can be reliably protected, Furthermore, the workpiece can be processed in an optimum state.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0014]
1 and 2 show an example of a mode for carrying out the laser processing apparatus of the present invention. In FIG. 1, 1 is a laser oscillator, 2 is a folding mirror for changing the transmission direction of the laser beam 3 for processing from the laser oscillator 1, and 4 is a laser beam 3 transmitted in a direction changed by the folding mirror 2. The folding mirror 5 for changing the transmission direction of the laser beam 5 is an incident condensing lens for condensing the laser light 3 transmitted by changing the direction by the folding mirror 4.
[0015]
6 is an optical fiber for transmitting the laser light 3 from the incident condensing lens 5, and 7 is a processing head having a condensing lens 9 for irradiating the workpiece 8 with the laser light 3 transmitted from the optical fiber 6. is there. Thus, the machining head 7 can be moved up and down via the feed screw shaft 11 and the nut 12 by driving a driving device 10 such as a servo motor. The focal point can be adjusted to the processing point P of the workpiece 8.
[0016]
Reference numeral 13 denotes a light detector such as a photosensor that detects the light intensity of the laser beam 3 that has passed through the reflection mirror 2 without being reflected, and transmits the detection signal V1 to the monitoring controller 14. Reference numeral 15 denotes a reflection from the workpiece 8. This is a photo detector such as a photo sensor that detects the light intensity of the reflected light 16 that returns and transmits through the folding mirror 4 and transmits it to the monitoring control device 14 as a detection signal V2.
[0017]
17 is switched by the interlock device 18 when any abnormality occurs in the transmission optical system such as the optical fiber 6, and is used to block the laser light 3 oscillated from the laser oscillator 1 and transmitted to the folding mirror 2. A shutter 19 is a beam damper for absorbing the laser light 3 from the shutter 17, and the monitoring control device 14 can give command signals V 3 and V 4 to the driving device 10 and the interlock device 18, respectively. .
[0018]
Reference numeral 20 denotes a focal position detector for detecting whether or not the focusing point of the condenser lens 9 is at the processing point P of the workpiece 8. The focal position detector 20 is rotated in the horizontal direction by the driving device 21. A plate-shaped jig 22 made of a highly reflective material for reflecting the laser beam 3 collected by the condenser lens 9 is provided.
[0019]
Reference numeral 23 denotes an alarm device that issues an alarm according to a command from the monitoring control device 14 when the light intensity of the reflected light 16 exceeds a preset threshold value.
[0020]
Next, the operation of the illustrated example will be described.
[0021]
When processing the workpiece 8, the shutter 17 is opened and is at the position indicated by the solid line in FIG. 1, and the processing head 7 is high so that the focal point of the condenser lens 9 is positioned at the processing point P of the workpiece 8. The jig 22 of the focus position detector 20 is rotated in the horizontal direction by the drive device 21.
[0022]
The laser beam 3 oscillated from the laser oscillator 1 is reflected by the folding mirrors 2 and 4 to change the transmission direction, introduced from the folding mirror 4 to the incident condensing lens 5, and condensed to the optical fiber 6. The light is incident, emitted from the tip of the optical fiber 6, collected by the condenser lens 9, and irradiated to the processing point P of the workpiece 8 to process the workpiece 8. Processing includes welding and cutting.
[0023]
During the above-described operation, a part of the laser beam 3 from the laser oscillator 1 passes through the folding mirror 2 and is detected by the photodetector 13, and is supplied to the monitoring controller 14 as a detection signal V1. The reflected light 16 reflected from the surface of the workpiece 8 reaches the folding mirror 4 through the condenser lens 9, the optical fiber 6 and the incident condenser lens 5 and is reflected toward the folding mirror 2. The reflected light 16 passes through the folding mirror 4 and is detected by the photodetector 15, and is given to the monitoring controller 14 as a detection signal V2.
[0024]
The monitoring control device 14 monitors and discriminates the processing state or the state of the apparatus based on the light intensity detection signal V2 from the light detector 15. That is, for example, when the detection signal V2 is lower than the light intensity threshold set in the monitoring control device 14 in advance, the processing state of the workpiece 8 is normal and no abnormality has occurred in the laser processing device. For this reason, the processing of the workpiece 8 is continued. In this case, the detection signal V1 from the light detector 13 and the detection signal V2 from the light detector 15 are compared to obtain a difference, and when the state is determined from the difference, the workpiece 8 is processed normally. It is possible to more accurately monitor whether or not an abnormality has occurred in the laser processing apparatus, and it is possible to cope with the case where the laser light 3 is pulsed light.
[0025]
Since the highly rotating material 22 is used for the horizontally rotating jig 22 of the focus position detector 20, when the jig 22 crosses the laser beam 3 on the upper surface of the workpiece 8, the light intensity of the reflected light 16 is high. Become. For this reason, based on the value of the detection signal V2 from the light detector 15, the monitoring controller 14 previously determines whether or not the focal point of the condensing lens 9 is at the processing point P of the workpiece 8 and how much it deviates. Is determined.
[0026]
Thus, when the focal point of the condenser lens 9 is not at the processing point P of the workpiece 8, the command signal V3 is given in advance from the monitoring control device 14 to the driving device 10, and the driving device 10 is driven. For this reason, the feed screw shaft 11 rotates, the processing head 7 extends, and the condensing lens 9 ascends and descends, the focal point thereof coincides with the processing point P of the workpiece 8, and automatic focus position correction is performed.
[0027]
If the detection signal V2 from the light detector 15 or the comparison between the detection signal V1 from the light detector 13 and the detection signal V2 from the light detector 15 is higher than the threshold, the monitoring control device 14 A command is given to the alarm device 23 so that the alarm device 23 notifies the processing state of the workpiece 8 and the abnormality of the laser processing device, and the command signal V4 is given from the monitoring control device 14 to the interlock device 18 to close the shutter 17. Therefore, the laser beam 3 oscillated from the laser oscillator 1 is blocked by the shutter 17 and absorbed by the beam damper 19. Therefore, the processing of the workpiece 8 is stopped and the laser processing apparatus can be prevented from being damaged by heat.
[0028]
According to the illustrated example, since the mechanism for monitoring the processing state of the workpiece 8 or the operating state of the apparatus is simple, it is possible to suppress the equipment cost and the operation maintenance cost, and the workpiece 8 Since the reflected light 16 reflected from the light is directly detected, the processing state of the workpiece 8 or the state of the apparatus can be monitored easily and reliably, and further the protection of the apparatus is ensured. In addition, the workpiece 8 can be processed in an optimum state.
[0029]
3 and 4 show another example of the embodiment of the laser processing apparatus according to the present invention. The laser processing apparatus basically includes the same components as those shown in FIGS. In FIG. 3, reference numeral 15 ′ denotes a photodetector such as a photosensor that can detect the light intensity of the reflected light that has been reflected by the workpiece 8 and returned and transmitted through the folding mirror 4. As shown in FIG. 4, the light detector 15 ′ has a detection surface divided into four parts, and can provide four detection signals V 21, V 22, V 23, V 24 to the monitoring controller 14.
[0030]
Reference numeral 24 denotes a bed for supporting the workpiece 8. The bed 24 can be moved in the X direction parallel to the paper surface when viewed in plan by a driving device 25 such as a servomotor, a servomotor, and the like. Is provided with a lower bed 28 that can be moved in the Y direction perpendicular to the paper surface as viewed in plan.
[0031]
The monitoring control device 14 can determine which position of the workpiece 8 is being processed in a plan view based on the detection signals V21, V22, V23, V24 from the photodetector 15 ′. At the same time, the monitoring control device 14 gives command signals V5 and V6 to the driving devices 25 and 27 of the bed 24 to drive the driving devices 25 and 27, and the processing surfaces of the upper and lower beds 26 and 28 are planar. Therefore, the machining position of the workpiece 8 can be corrected.
[0032]
The method of processing the workpiece 8 in the illustrated example is basically the same as that in the illustrated example of FIGS. 1 and 2, but in the illustrated example, the processing position of the workpiece 8 is corrected. This is different from the illustrated example in that respect. That is, in the illustrated example, a part of the reflected light 16 reflected and returned by the workpiece 8 is transmitted through the folding mirror 4 and detected by the photodetector 15 ′, and the light intensity detection signals V21, V22, V23 and V24 are given from the photodetector 15 'to the monitoring controller 14.
[0033]
In the monitoring control device 14, the detection signals V 21, V 22, V 23, V 24 are added to obtain a total detection signal V 1, which is compared with a preset light intensity threshold or from the light detector 13. Is compared with the detection signal V1 of the light intensity of the workpiece, and the processing state of the workpiece or the operating state of the apparatus is determined and monitored.
[0034]
Further, due to the voltage difference between the detection signals V21, V22, V23, and V24, the laser light 3 irradiated from the condenser lens 9 to the workpiece 8 is predetermined on the workpiece 8 in the plane direction of the workpiece 8. It is determined whether or not the processing point P is irradiated, and how much the focal point of the condenser lens 9 is shifted in the plane direction of the workpiece 8 with respect to the processing point P is determined. Then, the command signals V5 and V6 are given to the driving devices 25 and 27 from the monitoring control device 14, and the driving devices 25 and 27 are driven.
[0035]
Therefore, since the upper bed 26 is adjusted in the X direction and the lower bed 28 is adjusted in the Y direction, the workpiece 8 is adjusted so that the processing point P matches the focal point of the optical lens 9 in the plane direction. , Y is adjusted in both directions.
[0036]
Also in the illustrated example of the present invention, the mechanism for monitoring the processing state of the workpiece 8 or the operating state of the apparatus is simplified, and the equipment cost and the operation and maintenance cost can be suppressed as in the above-described illustrated example. In addition, since the reflected light 16 reflected from the workpiece 8 is directly detected, the processing state of the workpiece 8 or the state of the apparatus can be monitored easily and reliably. The apparatus can be reliably protected, and the workpiece 8 can be processed in an optimum state.
[0037]
In the illustrated example of the present invention, the light intensity of the laser light transmitted through the folding mirror is detected by a photodetector provided on the back surface of one folding mirror with two folding mirrors, and the other folding mirror. The case where the light intensity of the reflected light reflected by the workpiece and returned by the photodetector provided on the back surface of the mirror has been described. However, the angle of 90 ° is shifted to the back surface of one folding mirror. One light detector is provided, one of the light detectors detects the light intensity of the laser light that has passed through the folding mirror, and the other light detector reflects back from the workpiece. Needless to say, the present invention can be implemented by detecting the light intensity of the reflected light transmitted through the folding mirror, and various modifications can be made without departing from the scope of the present invention.
[0038]
【The invention's effect】
According to the laser processing apparatus of claims 1 to 6 of the present invention, the mechanism for monitoring the processing state of the workpiece or the operation state of the apparatus is simplified, and the equipment cost and the operation maintenance cost can be suppressed. In addition, since the reflected light reflected from the workpiece is directly detected, the machining state of the workpiece or the state of the apparatus can be monitored easily and reliably. Can be reliably protected, and further, various excellent effects such as being able to process the workpiece in an optimum state can be obtained.
[Brief description of the drawings]
FIG. 1 is a schematic view of a laser processing apparatus showing an example of an embodiment of the present invention.
FIG. 2 is a schematic plan view of a focal position detector applied to the apparatus of FIG.
FIG. 3 is a schematic diagram of a laser processing apparatus showing another example of the embodiment of the present invention.
4 is a front view of a photodetector applied to the apparatus shown in FIG. 3;
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Laser oscillator 2 Folding mirror 3 Laser beam 4 Folding mirror 5 Incident condensing lens 6 Optical fiber 7 Processing head 8 Work piece 9 Condensing lens 10 Driving device (means to move)
13 Photodetector 14 Monitoring and control device (means for determining, means for giving command)
15 Photo detector 15 'Photo detector 16 Reflected light 17 Shutter 18 Interlock device 19 Beam damper 20 Focus position detector 21 Drive device (moving means)
25 Drive unit (means for moving)
26 Upper bed (means to support)
27 Drive unit (means for moving)
28 Lower bed (means to support)
P Machining point V1 Detection signal V2 Detection signal V21 Detection signal V22 Detection signal V23 Detection signal V24 Detection signal V3 Command signal (command)
V4 command signal (command)
V5 command signal (command)
V6 command signal (command)

Claims

A laser oscillator, a folding mirror for reflecting the laser beam oscillated from the laser oscillator, an optical fiber for feeding transfer through the incident condenser lens of the laser beam reflected by the folding mirror, is transmitted by the optical fiber the laser beam and a is condensed by a condenser lens and irradiated to the workpiece machining head for machining the workpiece was,
A laser processing apparatus configured to reflect the laser light irradiated on the workpiece from the laser oscillator to the reflected light by the workpiece;
A photodetector for detecting the light intensity of the reflected light transmitted through and the return mirror is placed on the back of the folding mirror,
Means for comparing the detection signal of the light intensity detected by the light detector with a preset light intensity threshold value to determine whether the processing state of the workpiece or the operation state of the apparatus is normal;
A jig that rotates on the upper surface of the workpiece and crosses the laser beam is disposed so as to detect the focal position of the condenser lens provided in the processing head, and from the laser oscillator to the workpiece. A focal position detector that reflects the irradiated laser beam with the jig to make reflected light; and
A means for obtaining a shift of the focal point of the condenser lens with respect to a processing point of the workpiece from the reflected light reflected by the focal position detector, and for moving the processing head so as to approach or separate from the workpiece. Means for giving a command to move the processing head so that the focal point is aligned with a processing point of the workpiece;
The light detector for detecting the reflected light transmitted through the folding mirror is a light detector having a detection surface divided into four, and the light collecting lens is obtained from detection signals of a plurality of light intensities detected by the light detector. A means for giving a command to a means for moving the means for supporting the workpiece in the plane direction of the workpiece so as to eliminate the deviation, and obtaining a deviation of the focal point of the workpiece in the plane direction of the machining point;
A laser processing apparatus comprising:

A laser oscillator, a first folding mirror for reflecting the laser beam oscillated from the laser oscillator, a second folding mirror for reflecting the laser light reflected by the first folding mirror, said second the irradiated and the optical fiber to feed transfer through the incident condenser lens the laser beam reflected by the folding mirror and the laser light transmitted by the optical fiber is focused by a condenser lens to the workpiece A machining head for machining a workpiece ,
A laser processing apparatus configured to reflect the laser light irradiated on the workpiece from the laser oscillator to the reflected light by the workpiece;
A first photodetector for detecting the light intensity of the reflected light transmitted through the and the first or second fold mirror attached to the back surface of the first or second fold mirror,
Second optical detection for detecting the light intensity of the laser beam is oscillated from installed and the laser oscillator is transmitted through the second or first fold mirror to the back of the second or first fold mirror And
Actuation of said first, second machining state or apparatus of the workpiece as compared to a threshold value of the light intensities preset signal obtained by comparing with comparing the detection signal of the light intensity detected by the photodetector Means for determining whether the state is normal;
A jig that rotates on the upper surface of the workpiece and crosses the laser beam is disposed so as to detect the focal position of the condenser lens provided in the processing head, and from the laser oscillator to the workpiece. A focal position detector that reflects the irradiated laser beam with the jig to make reflected light; and
A means for obtaining a shift of the focal point of the condenser lens with respect to a processing point of the workpiece from the reflected light reflected by the focal position detector, and for moving the processing head so as to approach or separate from the workpiece. Means for giving a command to move the processing head so that the focal point is aligned with a processing point of the workpiece;
The second photodetector for detecting the reflected light transmitted through the second folding mirror is a photodetector having a detection surface divided into four, and detection signals of a plurality of light intensities detected by the photodetector. To determine the deviation of the focal point of the condenser lens in the plane direction of the machining point in the workpiece, and to move the means for supporting the workpiece in the plane direction of the workpiece so as to eliminate the deviation. Means for giving a command;
A laser processing apparatus comprising:

A laser oscillator, a folding mirror for reflecting the laser beam oscillated from the laser oscillator, an optical fiber for feeding transfer through the incident condenser lens the laser beam reflected by the folding mirror, transmitted by the optical fiber and a is condensed by irradiating the workpiece machining head for machining the workpiece by a condenser lens the laser beam,
A laser processing apparatus configured to reflect the laser light irradiated on the workpiece from the laser oscillator to the reflected light by the workpiece;
The for detecting the light intensity of the first light detector and the laser beam transmitted through the folding mirror for detecting the transmitted light intensity of the reflected light and the return mirror is placed on the back of the folding mirror Two photodetectors,
Actuation of said first, second machining state or apparatus of the workpiece as compared to a threshold value of the light intensities preset signal obtained by comparing with comparing the detection signal of the light intensity detected by the photodetector Means for determining whether the state is normal;
A jig that rotates on the upper surface of the workpiece and crosses the laser beam is disposed so as to detect the focal position of the condenser lens provided in the processing head, and from the laser oscillator to the workpiece. A focal position detector that reflects the irradiated laser beam with the jig to make reflected light; and
A means for obtaining a shift of the focal point of the condenser lens with respect to a processing point of the workpiece from the reflected light reflected by the focal position detector, and for moving the processing head so as to approach or separate from the workpiece. Means for giving a command to move the processing head so that the focal point is aligned with a processing point of the workpiece;
The second photodetector for detecting the reflected light transmitted through the folding mirror is a photodetector having a detection surface divided into four, and from the detection signals of a plurality of light intensities detected by the photodetector, A deviation of the focal point of the condenser lens in the plane direction of the machining point in the workpiece is obtained, and a command is given to the means for moving the means for supporting the workpiece in the plane direction of the workpiece so as to eliminate the deviation. Means,
A laser processing apparatus comprising:

And beam damper for absorbing a shutter to block the laser light transmitted to said folding mirror side oscillated from the laser oscillator, the laser light is blocked by the shutter, and the interlock device for driving the shutter, device when the operating state of erratically, laser machining apparatus according to claim 1, 2 or 3 provided with a means for giving a command to close the shutter to the interlock device.