JP2023135369A

JP2023135369A - Laser processing device

Info

Publication number: JP2023135369A
Application number: JP2022040533A
Authority: JP
Inventors: 知樹金武; Tomoki Kanetake; 智浩持山; Tomohiro Mochiyama; 恒之大口; Tsuneyuki Oguchi
Original assignee: Panasonic Intellectual Property Management Co Ltd
Current assignee: Panasonic Intellectual Property Management Co Ltd
Priority date: 2022-03-15
Filing date: 2022-03-15
Publication date: 2023-09-28

Abstract

To accurately control optical output to an emission head.SOLUTION: A laser processing device 100 is provided with a shield member 16 with an opening 16a so as to shield at least part of light other than first split beam LB3 proceeding toward a reception surface of a power monitor 14 and cause first split beam LB3 to pass through the opening 16a.SELECTED DRAWING: Figure 2

Description

本発明は、複数のレーザダイオードから出射されたレーザ光を集光して出射ヘッドから出射するレーザ加工装置に関する。 The present invention relates to a laser processing device that condenses laser light emitted from a plurality of laser diodes and emits it from an output head.

特許文献１には、レーザ光を出射するレーザダイオードと、レーザダイオードから出射されたレーザ光を集光するレンズからなる光合成部と、前記光合成部により出射されたレーザ光を、第１分割光及び第２分割光に分割する部分透過ミラーと、前記第１分割光を受光し、当該第１分割光の光量を検出するパワーモニタと、前記第２分割光を出射ヘッドに導く伝送ファイバと、前記パワーモニタの検出値を用いて指令値を算出する制御部と、前記制御部によって算出された前記指令値に応じた電流を前記レーザダイオードに供給する電源とを備えたレーザ加工装置が開示されている。 Patent Document 1 describes a laser diode that emits a laser beam, a light combining section that includes a lens that focuses the laser beam that is emitted from the laser diode, and a light combining section that combines the laser beam emitted by the light combining section into a first divided beam and a first divided beam. a partially transmitting mirror that divides the first divided light into a second divided light; a power monitor that receives the first divided light and detects the amount of the first divided light; a transmission fiber that guides the second divided light to the output head; A laser processing device is disclosed that includes a control unit that calculates a command value using a detected value of a power monitor, and a power source that supplies the laser diode with a current according to the command value calculated by the control unit. There is.

特許第６０５０６０７号公報Patent No. 6050607

ところで、特許文献１に開示されたようなレーザ加工装置では、レーザダイオードがレーザ光の出射を開始した直後に、レーザ加工装置内の温度変化により、伝送ファイバへの入射光の入射面における位置が本来の位置からずれるいわゆる光軸ずれが生じ、その結果伝送ファイバからの散乱光が増大する場合がある。また、レーザダイオードによりレーザ光が出射されている状態においては、レンズ等の光学素子に含まれる不純物、伝送ファイバの入射面等から一定の散乱光が常時発生している。これらの散乱光がレーザ加工装置の筐体内で多重反射した後パワーモニタに入射すると、パワーモニタの検出値が、出射ヘッドの実際の光出力（出射光の出力）に対応する値よりも大きくなり、出射ヘッドの光出力が想定値よりも小さく制御されてしまう。 By the way, in a laser processing device such as that disclosed in Patent Document 1, immediately after the laser diode starts emitting laser light, the position of the incident light on the incident surface of the transmission fiber changes due to a temperature change inside the laser processing device. A so-called optical axis misalignment, which deviates from the original position, may occur, and as a result, scattered light from the transmission fiber may increase. Furthermore, while the laser diode is emitting laser light, a certain amount of scattered light is always generated from impurities contained in optical elements such as lenses, the entrance surface of the transmission fiber, and the like. When these scattered lights enter the power monitor after multiple reflections within the housing of the laser processing equipment, the detected value of the power monitor becomes larger than the value corresponding to the actual optical output (output of the emitted light) of the output head. , the light output of the output head is controlled to be smaller than the expected value.

本発明は、かかる点に鑑みてなされたものであり、その目的とするところは、出射ヘッドの光出力を精度良く制御できるようにすることにある。 The present invention has been made in view of this point, and an object of the present invention is to enable accurate control of the light output of the emitting head.

上記の目的を達成するため、本発明は、レーザ光を出射する複数のレーザダイオードと、前記複数のレーザダイオードから出射されたレーザ光を集光してレーザビームを出射する光合成部と、前記光合成部により出射されたレーザビームを、第１分割ビーム及び第２分割ビームに分割する部分透過ミラーと、前記第１分割ビームを受光し、当該第１分割ビームの光量を検出するパワーモニタと、前記第２分割ビームに基づく出射用レーザ光を出射ヘッドに導く伝送ファイバと、前記パワーモニタの検出値を用いて指令値を算出する制御部と、前記制御部によって算出された前記指令値に応じた電流を前記複数のレーザダイオードに流す電源とを備えたレーザ加工装置であって、窓部を有し、前記パワーモニタの受光面に向かう前記第１分割ビーム以外の光の少なくとも一部を遮蔽し、かつ前記窓部によって前記第１分割ビームを通過させるように設けられた第１の遮蔽部材、窓部を有し、前記部分透過ミラーと前記伝送ファイバの入射面との間に、前記伝送ファイバの入射面からの散乱光の少なくとも一部を遮蔽し、かつ前記窓部によって前記第２分割ビームを通過させるように設けられた第２の遮蔽部材、及び窓部を有し、前記光合成部と前記部分透過ミラーとの間に、前記光合成部からの散乱光の少なくとも一部を遮蔽し、かつ前記窓部によって前記レーザビームを通過させるように設けられた第３の遮蔽部材のうちの少なくとも１つの遮蔽部材を備えていることを特徴とする。 In order to achieve the above object, the present invention includes a plurality of laser diodes that emit laser beams, a photosynthesizer that collects the laser beams emitted from the plurality of laser diodes and emits a laser beam, and a photosynthesizer that emits a laser beam. a partially transmitting mirror that splits the laser beam emitted by the part into a first split beam and a second split beam; a power monitor that receives the first split beam and detects the amount of light of the first split beam; a transmission fiber that guides the output laser beam based on the second split beam to the output head; a control unit that calculates a command value using the detection value of the power monitor; A laser processing device comprising: a power source that causes current to flow through the plurality of laser diodes, the laser processing device having a window portion and blocking at least a portion of light other than the first split beam directed toward the light receiving surface of the power monitor. , and a first shielding member provided to allow the first split beam to pass through the window, and a window, the transmission fiber being disposed between the partially transmitting mirror and the incident surface of the transmission fiber. a second shielding member provided to shield at least a part of the scattered light from the incident surface of the light beam and to allow the second split beam to pass through the window; At least one of the third shielding members provided between the partially transmitting mirror and the third shielding member so as to shield at least a part of the scattered light from the light combining section and to allow the laser beam to pass through the window section. It is characterized by comprising two shielding members.

本発明によれば、遮蔽部材を設けない場合に比べ、伝送ファイバからパワーモニタの受光面に達する散乱光、及び光合成部からパワーモニタの受光面に達する散乱光のうちの少なくとも一方の散乱光を減らせるので、制御部に、出射ヘッドの光出力をより精度良く制御させることができる。 According to the present invention, compared to the case where no shielding member is provided, at least one of the scattered light reaching the light receiving surface of the power monitor from the transmission fiber and the scattered light reaching the light receiving surface of the power monitor from the light combining section is reduced. Since the amount of light output can be reduced, the control section can control the light output of the output head with more precision.

本発明によれば、制御部に、出射ヘッドの光出力をより精度良く制御させることができる。 According to the present invention, the control unit can control the light output of the output head with higher precision.

本発明の実施形態１に係るレーザ加工装置の構成を示す模式図である。1 is a schematic diagram showing the configuration of a laser processing apparatus according to Embodiment 1 of the present invention. 本発明の実施形態１に係るレーザ加工装置のレーザ装置周りの構成を示す模式図である。1 is a schematic diagram showing a configuration around a laser device of a laser processing device according to Embodiment 1 of the present invention. レーザ光出射部及び光合成部の詳細な構成を示す模式図である。FIG. 2 is a schematic diagram showing a detailed configuration of a laser beam emitting section and a light combining section. 複数のレーザモジュールの構成を示す模式図である。FIG. 3 is a schematic diagram showing the configuration of a plurality of laser modules. レーザモジュールの側面図である。It is a side view of a laser module. レーザモジュールの正面図である。FIG. 3 is a front view of the laser module. 遮蔽部材の平面図である。It is a top view of a shielding member. 実施形態２の図２相当図である。FIG. 2 is a diagram corresponding to FIG. 2 of Embodiment 2; 実施形態３の図８相当図である。9 is a diagram corresponding to FIG. 8 of Embodiment 3. FIG.

以下、本発明の実施形態について図面に基づいて説明する。以下の好ましい実施形態の説明は、本質的に例示に過ぎず、本発明、その適用物或いはその用途を制限することを意図するものでは全くない。 Embodiments of the present invention will be described below based on the drawings. The following description of preferred embodiments is merely exemplary in nature and is in no way intended to limit the invention, its applications, or its uses.

（実施形態１）
図１は、金属製の加工対象物としてのワークＷの切断、溶接といったレーザ加工に用いられる本発明の実施形態１に係るレーザ加工装置１００を示す。同図に示すように、レーザ加工装置１００は、レーザ装置１０と伝送ファイバ４０と出射ヘッド５０と制御部６０と電源７０と指令部８０とを備えている。レーザ装置１０と、レーザ装置１０よりレーザ光が出射される端部（以下、単に出射端という。）と、レーザ装置１０より伝送ファイバ４０にレーザ光が入射される端部（以下、単に入射端という。）とは筐体９０に収容されている。 (Embodiment 1)
FIG. 1 shows a laser processing apparatus 100 according to a first embodiment of the present invention, which is used for laser processing such as cutting and welding a work W as a metal workpiece. As shown in the figure, the laser processing apparatus 100 includes a laser device 10, a transmission fiber 40, an emission head 50, a control section 60, a power source 70, and a command section 80. The laser device 10, the end where the laser light is emitted from the laser device 10 (hereinafter simply referred to as the output end), and the end where the laser light is input from the laser device 10 to the transmission fiber 40 (hereinafter simply referred to as the input end) ) is housed in the housing 90.

レーザ装置１０は、図２に示すように、レーザ光出射部１１と、光合成部１２と、部分透過ミラー１３と、パワーモニタ１４と、集光ユニット１５と、遮蔽部材１６とを備えている。 As shown in FIG. 2, the laser device 10 includes a laser beam emitting section 11, a light combining section 12, a partially transmitting mirror 13, a power monitor 14, a condensing unit 15, and a shielding member 16.

レーザ光出射部１１は、図３に示すように、互いに異なる波長のレーザ光ＬＢ１を発する例えば１０個のレーザモジュール３０を有している。各レーザモジュール３０は、図４～６に示すように、レーザダイオードバー（ＬＤバー）３１を有しており、レーザダイオードバー３１は、並列に配置された複数のエミッタ３１ｂを有する半導体レーザアレイである。言い換えるとレーザダイオードバー３１は、エミッタ３１ｂを有する並列に配置された複数のレーザダイオードからなる半導体レーザアレイである。レーザダイオードバー３１は、平面視矩形状の平板形状をなし、その一方の面には板状の正電極３２が配置され、正電極３２の一方の面が取り付けられている。また、レーザダイオードバー３１の他方の面には、正電極３２よりも広い板状の負電極３３が配置され、負電極３３の一方の面の一部が取り付けられている。レーザダイオードバー３１の一側面が、レーザ光ＬＢ１を出射するレーザ光出射面３１ａを構成している。各電極（正電極３２，負電極３３）には、配線３５が接続され、当該配線３５を介して後述する電源７０から電流（電力）が供給される。なお、一つのレーザダイオードバー３１に含まれるエミッタ３１ｂの個数は、例えば５０個に設定される。１０個のレーザモジュール３０のレーザダイオードバー３１は、互いに直列に接続されている。 As shown in FIG. 3, the laser beam emitting unit 11 includes, for example, ten laser modules 30 that emit laser beams LB1 of mutually different wavelengths. As shown in FIGS. 4 to 6, each laser module 30 has a laser diode bar (LD bar) 31, and the laser diode bar 31 is a semiconductor laser array having a plurality of emitters 31b arranged in parallel. be. In other words, the laser diode bar 31 is a semiconductor laser array consisting of a plurality of laser diodes arranged in parallel and having an emitter 31b. The laser diode bar 31 has a rectangular plate shape in plan view, and a plate-shaped positive electrode 32 is disposed on one surface thereof, and one surface of the positive electrode 32 is attached. Moreover, a plate-shaped negative electrode 33 wider than the positive electrode 32 is arranged on the other surface of the laser diode bar 31, and a part of one surface of the negative electrode 33 is attached. One side of the laser diode bar 31 constitutes a laser light emitting surface 31a that emits the laser light LB1. A wiring 35 is connected to each electrode (positive electrode 32, negative electrode 33), and current (power) is supplied from a power source 70, which will be described later, via the wiring 35. Note that the number of emitters 31b included in one laser diode bar 31 is set to 50, for example. Laser diode bars 31 of ten laser modules 30 are connected to each other in series.

光合成部１２は、レーザ光出射部１１に含まれる複数のレーザダイオードから出射されたレーザ光ＬＢ１を集光してレーザビームＬＢ２を出射する。具体的には、光合成部１２は、１０個のレーザモジュール３０からそれぞれ出射されたレーザ光ＬＢ１を集光してレーザビームＬＢ２を出射する第１集光レンズ１２ａと、第１集光レンズ１２ａにより出射されたレーザビームＬＢ２を反射させる反射鏡１２ｂとを備えた光学ユニットである。 The light combining section 12 condenses the laser beams LB1 emitted from the plurality of laser diodes included in the laser beam emitting section 11 and emits a laser beam LB2. Specifically, the light combining unit 12 includes a first condenser lens 12a that condenses laser beams LB1 emitted from each of the ten laser modules 30 and emits a laser beam LB2, and a first condenser lens 12a. This optical unit includes a reflecting mirror 12b that reflects the emitted laser beam LB2.

部分透過ミラー１３は、光合成部１２の反射鏡１２ｂにより出射されたレーザビームＬＢ２を、第１分割ビームＬＢ３及び第２分割ビームＬＢ４に分割する。具体的には、部分透過ミラー１３は、光合成部１２の反射鏡１２ｂにより出射されたレーザビームＬＢ２の一部を第１分割ビームＬＢ３として透過させる一方、残りを第２分割ビームＬＢ４として反射させる。部分透過ミラー１３の反射率は、９９．５％～９９．９％に設定される。 The partially transmitting mirror 13 divides the laser beam LB2 emitted by the reflecting mirror 12b of the light combining section 12 into a first divided beam LB3 and a second divided beam LB4. Specifically, the partially transmitting mirror 13 transmits a part of the laser beam LB2 emitted by the reflecting mirror 12b of the light combining section 12 as a first divided beam LB3, and reflects the remainder as a second divided beam LB4. The reflectance of the partially transmitting mirror 13 is set to 99.5% to 99.9%.

パワーモニタ１４は、部分透過ミラー１３を透過した第１分割ビームＬＢ３の光量を検出する。パワーモニタ１４は、例えば、第１分割ビームＬＢ３を減衰させて出力する減衰部と、減衰部の出力を検出するフォトダイオードとで構成される。 The power monitor 14 detects the amount of light of the first divided beam LB3 that has passed through the partially transmitting mirror 13. The power monitor 14 includes, for example, an attenuation section that attenuates and outputs the first divided beam LB3, and a photodiode that detects the output of the attenuation section.

集光ユニット１５は、部分透過ミラー１３を反射した第２分割ビームＬＢ４を集光し、所定の倍率でビーム径を縮小し、第２分割ビームＬＢ４に基づく出射用レーザ光ＬＢ５を伝送ファイバ４０に入射させる第２集光レンズ１５ａと、伝送ファイバ４０の入射端が接続されるコネクタ（図示せず）とを有している。 The condensing unit 15 condenses the second divided beam LB4 reflected by the partially transmitting mirror 13, reduces the beam diameter by a predetermined magnification, and transmits the output laser beam LB5 based on the second divided beam LB4 to the transmission fiber 40. It has a second condensing lens 15a through which the light is incident, and a connector (not shown) to which the input end of the transmission fiber 40 is connected.

遮蔽部材１６は、図７に示すように、長方形板状に形成されている。遮蔽部材１６は、アルマイト処理されたアルミニウムで構成されている。なお、遮蔽部材１６を、アルミニウム合金、銅、鉄、ステンレス等の他の金属で構成してもよい。遮蔽部材１６の長手方向中央の短手方向中央には、正方形状の窓部としての開口部１６ａが形成されている。遮蔽部材１６は、部分透過ミラー１３とパワーモニタ１４の間に、筐体９０内の空間を、部分透過ミラー１３側の空間とパワーモニタ１４側の空間とに仕切るように設けられている。つまり、遮蔽部材１６の外周端縁は、全周に亘って筐体９０の内面に隙間なく当接しているか又は溶接されている。 The shielding member 16 is formed into a rectangular plate shape, as shown in FIG. The shielding member 16 is made of alumite-treated aluminum. Note that the shielding member 16 may be made of other metals such as aluminum alloy, copper, iron, and stainless steel. An opening 16a serving as a square window is formed at the center in the longitudinal direction and the center in the width direction of the shielding member 16. The shielding member 16 is provided between the partially transmitting mirror 13 and the power monitor 14 so as to partition the space inside the housing 90 into a space on the partially transmitting mirror 13 side and a space on the power monitor 14 side. That is, the outer peripheral edge of the shielding member 16 is in contact with the inner surface of the casing 90 without any gap or is welded over the entire circumference.

遮蔽部材１６の開口部１６ａは、部分透過ミラー１３を透過した第１分割ビームＬＢ３を通過させる。また、遮蔽部材１６は、パワーモニタ１４の受光面に向かう第１分割ビームＬＢ３以外の光の少なくとも一部を遮蔽する。つまり、遮蔽部材１６は、パワーモニタ１４の受光面に向かう第１分割ビームＬＢ３以外の光の少なくとも一部を遮蔽し、かつ開口部１６ａによって第１分割ビームＬＢ３を通過させるように配置されている。 The opening 16a of the shielding member 16 allows the first split beam LB3 that has passed through the partially transmitting mirror 13 to pass therethrough. Further, the shielding member 16 shields at least a portion of the light other than the first divided beam LB3 directed toward the light receiving surface of the power monitor 14. That is, the shielding member 16 is arranged to shield at least a portion of the light other than the first divided beam LB3 directed toward the light receiving surface of the power monitor 14, and to allow the first divided beam LB3 to pass through the opening 16a. .

第１分割ビームＬＢ３の半径ｒが２ｍｍであり、第１分割ビームＬＢ３の断面積が１２．５７ｍｍ^２である場合、遮蔽部材１６が第１分割ビームＬＢ３を遮断しないように、例えば、開口部１６ａの一辺の長さＬ１は８ｍｍ、開口部１６ａの面積は６４ｍｍ^２に設定される。 When the radius r of the first divided beam LB3 is 2 mm and the cross-sectional area of the first divided beam LB3 is 12.57 ^mm2 , for example, the opening 16a is The length L1 of one side is set to 8 mm, and the area of the opening 16a is set to 64 mm ² .

ここで、遮蔽部材１６（長方形）の面積をＳｔ、開口部１６ａの面積をＳａとする。第１分割ビームＬＢ３以外の光（雑光）の強度は、一様に分布すると考えられるので、遮蔽部材１６を設けることにより、パワーモニタ１４の受光面に入射する雑光の影響を、遮蔽部材１６を設けない場合のＳａ／Ｓｔに低減できる。遮蔽部材１６の長辺の長さＬＬが１００ｍｍ、遮蔽部材１６の短辺の長さＬＳが４０ｍｍ、開口部１６ａの一辺の長さＬ１が８ｍｍである場合、Ｓｔが４０００ｍｍ^２、Ｓａが６４ｍｍ^２となるので、パワーモニタ１４の受光面に入射する雑光の影響を、遮蔽部材１６を設けない場合の１．６％に低減できる。 Here, the area of the shielding member 16 (rectangular) is St, and the area of the opening 16a is Sa. Since the intensity of light other than the first divided beam LB3 (miscellaneous light) is considered to be uniformly distributed, by providing the shielding member 16, the influence of the miscellaneous light incident on the light receiving surface of the power monitor 14 can be reduced by the shielding member. Sa/St can be reduced to that in the case where 16 is not provided. When the length LL of the long side of the shielding member 16 is 100 mm, the length LS of the short side of the shielding member 16 is 40 mm, and the length L1 of one side of the opening 16a is 8 mm, St is 4000 mm ² and Sa is 64 mm ² Therefore, the influence of miscellaneous light incident on the light receiving surface of the power monitor 14 can be reduced to 1.6% of that in the case where the shielding member 16 is not provided.

伝送ファイバ４０は、集光ユニット１５の第２集光レンズ１５ａに光学的に結合され、当該第２集光レンズ１５ａを介してレーザ装置１０から受け取った出射用レーザ光ＬＢ５を出射ヘッド５０に導く。 The transmission fiber 40 is optically coupled to the second condenser lens 15a of the condenser unit 15, and guides the output laser beam LB5 received from the laser device 10 to the output head 50 via the second condenser lens 15a. .

出射ヘッド５０は、伝送ファイバ４０から出力される出射用レーザ光ＬＢ５を外部に向けて照射する。例えば、出射ヘッド５０は、所定の位置に配置されたワークＷに向けて、出射用レーザ光ＬＢ５を出射する。このようにすることで、ワークＷにレーザ加工が施される。 The output head 50 irradiates the output laser beam LB5 outputted from the transmission fiber 40 to the outside. For example, the emission head 50 emits the emission laser beam LB5 toward the work W placed at a predetermined position. By doing so, the workpiece W is subjected to laser processing.

制御部６０は、レーザ装置１０のレーザ発振を制御する。具体的には、制御部６０は、パワーモニタ１４の検出値を用いて、当該パワーモニタ１４の検出値が所定の設定値となるように、電源７０に出力する電流指令値の算出を行うフィードバック制御を行う。 The control unit 60 controls laser oscillation of the laser device 10. Specifically, the control unit 60 uses the detected value of the power monitor 14 to perform feedback to calculate a current command value to be output to the power source 70 so that the detected value of the power monitor 14 becomes a predetermined set value. Take control.

電源７０は、制御部６０によって算出された電流指令値に応じた電流を、前記レーザ光出射部１１に含まれるレーザダイオードバー３１及び配線３５に流す。 The power supply 70 causes a current according to the current command value calculated by the control section 60 to flow through the laser diode bar 31 and the wiring 35 included in the laser beam emitting section 11 .

指令部８０は、出射ヘッド５０の光出力（出射光の出力）の目標値を示す入力をユーザから受け付け、当該目標値を示す指令信号を制御部６０に出力する。 The command unit 80 receives an input from the user indicating a target value of the optical output (output of emitted light) of the emission head 50, and outputs a command signal indicating the target value to the control unit 60.

上述のように構成されたレーザ加工装置１００では、レーザ光出射部１１がレーザ光ＬＢ１の出射を開始すると、光合成部１２が、レーザ光ＬＢ１を集光してレーザビームＬＢ２を出射する。このレーザビームＬＢ２は、部分透過ミラー１３で第１分割ビームＬＢ３及び第２分割ビームＬＢ４に分割される。第１分割ビームＬＢ３は、遮蔽部材１６の開口部１６ａを通過してパワーモニタ１４に入射する一方、第２分割ビームＬＢ４は集光ユニット１５で集光されて出射用レーザ光ＬＢ５として伝送ファイバ４０に入射する。このとき、レーザ加工装置１００内の温度変化により、伝送ファイバ４０への入射光の入射面における位置が本来の位置からずれるいわゆる光軸ずれが生じ、その結果伝送ファイバ４０からの散乱光ＳＬが増大する。また、レーザ光出射部１１がレーザ光ＬＢ１を出射する間、常に、光合成部１２の第１集光レンズ１２ａ等の光学素子に含まれる不純物等や伝送ファイバ４０の入射面（入射端面）から常に一定の散乱光ＳＬが発生する。これら散乱光ＳＬの一部は、筐体９０内で多重反射してパワーモニタ１４の受光面に向かう。しかし、大部分の散乱光ＳＬは、パワーモニタ１４の受光面に達する前に遮蔽部材１６によって遮蔽される。これにより、遮蔽部材１６を設けない場合に比べ、光合成部１２からパワーモニタ１４の受光面に達する散乱光ＳＬ、及び伝送ファイバ４０からパワーモニタ１４の受光面に達する散乱光ＳＬが減る。したがって、制御部６０に、出射ヘッド５０の光出力をより精度良く制御させることができる。 In the laser processing apparatus 100 configured as described above, when the laser beam emitting section 11 starts emitting the laser beam LB1, the light combining section 12 condenses the laser beam LB1 and emits the laser beam LB2. This laser beam LB2 is split by a partially transmitting mirror 13 into a first split beam LB3 and a second split beam LB4. The first divided beam LB3 passes through the opening 16a of the shielding member 16 and enters the power monitor 14, while the second divided beam LB4 is condensed by the condensing unit 15 and sent to the transmission fiber 40 as an output laser beam LB5. incident on . At this time, due to the temperature change inside the laser processing device 100, a so-called optical axis shift occurs in which the position of the incident light on the transmission fiber 40 on the incident surface shifts from its original position, and as a result, the scattered light SL from the transmission fiber 40 increases. do. In addition, while the laser beam emitting section 11 emits the laser beam LB1, impurities contained in optical elements such as the first condensing lens 12a of the light combining section 12 and the incident surface (incident end surface) of the transmission fiber 40 are always removed. A certain amount of scattered light SL is generated. A portion of these scattered lights SL undergoes multiple reflections within the housing 90 and heads towards the light receiving surface of the power monitor 14 . However, most of the scattered light SL is blocked by the shielding member 16 before reaching the light receiving surface of the power monitor 14. This reduces the scattered light SL reaching the light receiving surface of the power monitor 14 from the light combining section 12 and the scattered light SL reaching the light receiving surface of the power monitor 14 from the transmission fiber 40, compared to the case where the shielding member 16 is not provided. Therefore, the control unit 60 can control the optical output of the output head 50 with more precision.

本実施形態１によると、遮蔽部材１６を部分透過ミラー１３とパワーモニタ１４との間に設けたので、部分透過ミラー１３と伝送ファイバ４０の入射面との間に設けた場合に比べ、遮蔽部材１６に入射する伝送ファイバ４０からの散乱光ＳＬが少なくなり、遮蔽部材１６に吸収される散乱光ＳＬのエネルギーが小さくなる。したがって、出射ヘッド５０に出射させる出射用レーザ光ＬＢ５をｋＷ級とする場合でも、遮蔽部材１６を冷却するための冷却機構を不要にでき、レーザ加工装置１００の設備コストを削減できる。 According to the first embodiment, since the shielding member 16 is provided between the partially transmitting mirror 13 and the power monitor 14, the shielding member 16 is provided between the partially transmitting mirror 13 and the incident surface of the transmission fiber 40. The scattered light SL from the transmission fiber 40 that enters the shielding member 16 is reduced, and the energy of the scattered light SL absorbed by the shielding member 16 is reduced. Therefore, even when the output laser beam LB5 to be outputted to the output head 50 is of kW class, a cooling mechanism for cooling the shielding member 16 can be made unnecessary, and the equipment cost of the laser processing apparatus 100 can be reduced.

また、遮蔽部材１６を光合成部１２と部分透過ミラー１３との間に設けた場合に比べ、パワーモニタ１４の受光面に達する伝送ファイバ４０からの散乱光ＳＬを効果的に減らせる。また、遮蔽部材１６を光合成部１２と部分透過ミラー１３との間に設けた場合に比べ、伝送ファイバ４０からの散乱光ＳＬが遮蔽部材１６で反射してパワーモニタ１４の受光面に達するのを抑制できる。 Furthermore, compared to the case where the shielding member 16 is provided between the light combining section 12 and the partially transmitting mirror 13, the scattered light SL from the transmission fiber 40 that reaches the light receiving surface of the power monitor 14 can be effectively reduced. Furthermore, compared to the case where the shielding member 16 is provided between the light combining section 12 and the partially transmitting mirror 13, the scattered light SL from the transmission fiber 40 is reflected by the shielding member 16 and reaches the light receiving surface of the power monitor 14. It can be suppressed.

（実施形態２）
図８は、実施形態２の図２相当図である。本実施形態２では、遮蔽部材１６が、光合成部１２と部分透過ミラー１３との間に２つ（複数）設けられている。これら２つの遮蔽部材１６は、板厚方向に互いに間隔を空けて互いに平行に設けられている。 (Embodiment 2)
FIG. 8 is a diagram corresponding to FIG. 2 of the second embodiment. In the second embodiment, two (plural) shielding members 16 are provided between the light combining section 12 and the partially transmitting mirror 13. These two shielding members 16 are provided parallel to each other and spaced apart from each other in the thickness direction.

そして、第１分割ビームＬＢ３は、２つの遮蔽部材１６の開口部１６ａを通過してパワーモニタ１４に入射する。 The first divided beam LB3 then passes through the openings 16a of the two shielding members 16 and enters the power monitor 14.

その他の構成は実施形態１と同じであるので、同一の構成箇所には同一の符号を付してその詳細な説明を省略する。 Since the other configurations are the same as those of the first embodiment, the same components are denoted by the same reference numerals and detailed explanation thereof will be omitted.

したがって、本実施形態２では、実施形態１のように遮蔽部材１６を１つだけ設けた場合に比べ、光合成部１２からパワーモニタ１４の受光面に達する散乱光ＳＬ、及び伝送ファイバ４０からパワーモニタ１４の受光面に達する散乱光ＳＬを減らし、制御部６０に、出射ヘッド５０の光出力をより精度良く制御させることができる。 Therefore, in the second embodiment, compared to the case where only one shielding member 16 is provided as in the first embodiment, the scattered light SL reaching the light receiving surface of the power monitor 14 from the light combining unit 12 and the power monitor from the transmission fiber 40 are It is possible to reduce the scattered light SL reaching the light-receiving surface of 14, and to have the control unit 60 control the light output of the output head 50 with more precision.

具体的には、遮蔽部材１６の長辺の長さＬＬが１００ｍｍ、遮蔽部材１６の短辺の長さＬＳが４０ｍｍ、開口部１６ａの一辺の長さＬ１が８ｍｍである場合、パワーモニタ１４の受光面に入射する雑光の影響を、遮蔽部材１６を設けない場合の０．０２６％（＝（Ｓａ／Ｓｔ）^２）に低減できる。 Specifically, when the length LL of the long side of the shielding member 16 is 100 mm, the length LS of the short side of the shielding member 16 is 40 mm, and the length L1 of one side of the opening 16a is 8 mm, the power monitor 14 The influence of miscellaneous light incident on the light receiving surface can be reduced to 0.026% (=(Sa/St) ² ) of the case where the shielding member 16 is not provided.

（実施形態３）
図９は、実施形態３の図８相当図である。本実施形態３では、２つの遮蔽部材１６のうち部分透過ミラー１３側の遮蔽部材１６の開口部１６ａの外周縁に、断面正方形状をなす角筒形状の筒状部１６ｂが部分透過ミラー１３側に向けて一体に突設されている。筒状部１６ｂは、遮蔽部材１６の板状の部分と同じ材料で構成されている。筒状部１６の内面には、光の反射を抑制するために微細な凹凸が全体に亘って形成されている。 (Embodiment 3)
FIG. 9 is a diagram corresponding to FIG. 8 of the third embodiment. In the third embodiment, a rectangular tube-shaped cylindrical portion 16b with a square cross section is attached to the outer periphery of the opening 16a of the shielding member 16 on the partially transmitting mirror 13 side of the two shielding members 16. It is integrally protruded towards. The cylindrical portion 16b is made of the same material as the plate-shaped portion of the shielding member 16. Fine irregularities are formed over the entire inner surface of the cylindrical portion 16 in order to suppress reflection of light.

そして、第１分割ビームＬＢ３は、部分透過ミラー１３側の遮蔽部材１６の筒状部１６ｂ及び開口部１６ａと、パワーモニタ１４側の遮蔽部材１６の開口部１６ａとを通過してパワーモニタ１４に入射する。 The first divided beam LB3 then passes through the cylindrical portion 16b and opening 16a of the shielding member 16 on the side of the partially transmitting mirror 13 and the opening 16a of the shielding member 16 on the side of the power monitor 14 to reach the power monitor 14. incident.

その他の構成は実施形態２と同じであるので、同一の構成箇所には同一の符号を付してその詳細な説明を省略する。 Since the other configurations are the same as those of the second embodiment, the same components are given the same reference numerals and detailed explanation thereof will be omitted.

したがって、本実施形態３では、実施形態２のようにいずれの遮蔽部材１６にも筒状部１６ｂを設けない場合に比べ、光合成部１２からパワーモニタ１４の受光面に達する散乱光ＳＬ、及び伝送ファイバ４０からパワーモニタ１４の受光面に達する散乱光ＳＬを減らせる。特に、筐体９０の内壁を反射してパワーモニタ１４の受光面に達する散乱光ＳＬを効果的に減らせる。したがって、制御部６０に、出射ヘッド５０の光出力をより精度良く制御させることができる。 Therefore, in the third embodiment, the scattered light SL reaching the light receiving surface of the power monitor 14 from the light combining section 12 and the transmitted Scattered light SL reaching the light receiving surface of the power monitor 14 from the fiber 40 can be reduced. In particular, the scattered light SL that is reflected off the inner wall of the housing 90 and reaches the light receiving surface of the power monitor 14 can be effectively reduced. Therefore, the control unit 60 can control the optical output of the output head 50 with more precision.

なお、上記実施形態１～３では、遮蔽部材１６を、部分透過ミラー１３とパワーモニタ１４との間に、開口部１６ａによって第１分割ビームＬＢ３を通過させるように配置した。しかし、遮蔽部材１６（第２の遮蔽部材）を、部分透過ミラー１３と伝送ファイバ４０の入射面との間に、伝送ファイバ４０の入射面からの散乱光ＳＬの少なくとも一部を遮蔽し、かつ開口部１６ａによって第２分割ビームＬＢ４を通過させるように配置してもよい。また、遮蔽部材１６（第３の遮蔽部材）を、光合成部１２と部分透過ミラー１３との間に、光合成部１２からの散乱光ＳＬの少なくとも一部を遮蔽し、かつ開口部１６ａによってレーザビームＬＢ２を通過させるように配置してもよい。また、レーザ加工装置１００に、上述のように開口部１６ａによって第１分割ビームＬＢ３を通過させる遮蔽部材１６、上述のように開口部１６ａによって第２分割ビームＬＢ４を通過させる遮蔽部材１６、及び上述のように開口部１６ａによってレーザビームＬＢ２を通過させる遮蔽部材１６のうちの２つ以上を設けてもよい。 In the first to third embodiments described above, the shielding member 16 is arranged between the partially transmitting mirror 13 and the power monitor 14 so that the first divided beam LB3 passes through the opening 16a. However, the shielding member 16 (second shielding member) is provided between the partially transmitting mirror 13 and the entrance surface of the transmission fiber 40 to shield at least a part of the scattered light SL from the entrance surface of the transmission fiber 40, and The second split beam LB4 may be arranged to pass through the opening 16a. Further, a shielding member 16 (third shielding member) is provided between the light combining unit 12 and the partially transmitting mirror 13 to shield at least a part of the scattered light SL from the light combining unit 12, and to provide a laser beam through the opening 16a. It may be arranged to allow LB2 to pass through. The laser processing apparatus 100 also includes a shielding member 16 that allows the first divided beam LB3 to pass through the opening 16a as described above, a shielding member 16 that allows the second divided beam LB4 to pass through the opening 16a as described above, and the shielding member 16 that allows the second divided beam LB4 to pass through the opening 16a as described above. Two or more of the shielding members 16 may be provided to allow the laser beam LB2 to pass through the opening 16a, as shown in FIG.

また、上記実施形態２，３では、遮蔽部材１６を２つ設けたが、３つ以上設けてもよい。 Further, in the second and third embodiments, two shielding members 16 are provided, but three or more shielding members 16 may be provided.

本発明のレーザ加工装置は、制御部に、出射ヘッドの光出力を精度良く制御させることができ、複数のレーザダイオードから出射されたレーザ光を集光して出射ヘッドから出射するレーザ加工装置として有用である。 The laser processing device of the present invention allows the control unit to control the light output of the output head with high precision, and can be used as a laser processing device that condenses laser light emitted from a plurality of laser diodes and outputs it from the output head. Useful.

１００レーザ加工装置
１２光合成部
１３部分透過ミラー
１４パワーモニタ
１６遮蔽部材
１６ａ開口部（窓部）
１６ｂ筒状部
３１レーザダイオードバー
ＬＢ１レーザ光
ＬＢ２レーザビーム
ＬＢ３第１分割ビーム
ＬＢ４第２分割ビーム
ＬＢ５出射用レーザ光 100 Laser processing device 12 Photosynthesis section
13 Partially transparent mirror
14 Power monitor
16 Shielding member
16a Opening (window)
16b Cylindrical part
31 Laser diode bar LB1 Laser beam LB2 Laser beam LB3 First divided beam LB4 Second divided beam LB5 Emission laser beam

Claims

multiple laser diodes that emit laser light,
a light combining unit that collects laser beams emitted from the plurality of laser diodes and emits a laser beam;
a partially transmitting mirror that divides the laser beam emitted by the light combining section into a first divided beam and a second divided beam;
a power monitor that receives the first divided beam and detects the amount of light of the first divided beam;
a transmission fiber that guides an output laser beam based on the second split beam to an output head;
a control unit that calculates a command value using the detected value of the power monitor;
A laser processing device comprising: a power source that causes a current to flow through the plurality of laser diodes according to the command value calculated by the control unit,
a first split beam having a window portion, the first split beam blocking at least a portion of light other than the first split beam directed toward the light receiving surface of the power monitor, and allowing the first split beam to pass through the window portion; shielding member,
a window portion is provided between the partially transmitting mirror and the entrance surface of the transmission fiber, the window portion blocks at least a part of the scattered light from the entrance surface of the transmission fiber, and the window portion blocks the second split beam. a second shielding member provided to allow the light to pass through, and a second shielding member having a window portion between the light combining unit and the partially transmitting mirror, shielding at least a part of the scattered light from the light combining unit, and A laser processing apparatus comprising at least one shielding member of a third shielding member provided so that the laser beam passes through the window.

The laser processing apparatus according to claim 1,
A laser processing apparatus, wherein the at least one shielding member includes the first shielding member.

The laser processing apparatus according to claim 2,
A laser processing apparatus characterized in that the at least one shielding member includes a plurality of the first shielding members formed at intervals.

In the laser processing apparatus according to any one of claims 1 to 3,
A laser processing device characterized in that a cylindrical portion is provided protruding from an outer peripheral edge of the window portion of the at least one shielding member.