JPS60263827A - Monitor device for optical fiber break accident - Google Patents

Monitor device for optical fiber break accident

Info

Publication number
JPS60263827A
JPS60263827A JP11959184A JP11959184A JPS60263827A JP S60263827 A JPS60263827 A JP S60263827A JP 11959184 A JP11959184 A JP 11959184A JP 11959184 A JP11959184 A JP 11959184A JP S60263827 A JPS60263827 A JP S60263827A
Authority
JP
Japan
Prior art keywords
optical fiber
laser beam
level
signal
output
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
JP11959184A
Other languages
Japanese (ja)
Inventor
Keiji Okino
沖野 圭司
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
NEC Corp
Original Assignee
NEC Corp
Nippon Electric Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by NEC Corp, Nippon Electric Co Ltd filed Critical NEC Corp
Priority to JP11959184A priority Critical patent/JPS60263827A/en
Publication of JPS60263827A publication Critical patent/JPS60263827A/en
Pending legal-status Critical Current

Links

Classifications

    • GPHYSICS
    • G01MEASURING; TESTING
    • G01MTESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
    • G01M11/00Testing of optical apparatus; Testing structures by optical methods not otherwise provided for
    • G01M11/30Testing of optical devices, constituted by fibre optics or optical waveguides
    • G01M11/33Testing of optical devices, constituted by fibre optics or optical waveguides with a light emitter being disposed at one fibre or waveguide end-face, and a light receiver at the other end-face
    • G01M11/333Testing of optical devices, constituted by fibre optics or optical waveguides with a light emitter being disposed at one fibre or waveguide end-face, and a light receiver at the other end-face using modulated input signals
    • G01M11/334Testing of optical devices, constituted by fibre optics or optical waveguides with a light emitter being disposed at one fibre or waveguide end-face, and a light receiver at the other end-face using modulated input signals with light chopping means

Landscapes

  • Physics & Mathematics (AREA)
  • Optics & Photonics (AREA)
  • Chemical & Material Sciences (AREA)
  • Analytical Chemistry (AREA)
  • General Physics & Mathematics (AREA)
  • Testing Of Optical Devices Or Fibers (AREA)
  • Light Guides In General And Applications Therefor (AREA)

Abstract

PURPOSE:To increase safety and to prevent a secondary disaster by stopping the oscillation of the 1st laser light when it is judged that an optical fiber is broken. CONSTITUTION:He-Ne Laser light modulated by a vane 4 is made incident on a detector 12 and converted by an electric signal, which is inputted to a comparator 17 through a capacitor 13, amplifier 14, band-pass filter 15, and integrator 16. Then, the comparator 17 outputs a low-level signal when the level of the input signal is higher than a specific value or a high-level signal when not. A shutter driving signal which has a high level only when a shutter 7 is open is outputted from the shutter 7 and this shutter driving signal is ANDed with the output signal of the comparator 17 by a gate 18. Therefore, only when a YAG laser device 1 oscillates and the output level of the He-Ne laser light transmitted through the optical fiber is smaller than a specific value, the shutter 7 is closed with the high-level output of the circuit 18, thereby stopping the oscillation of the YAG laser.

Description

【発明の詳細な説明】 〔技術分野〕 本発明は、レーザ加工装置における光ファイバの破断を
実時間で検知し、災害を未然に防止する光フアイバ破断
事故監視装置に関するものである。
DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to an optical fiber breakage accident monitoring device that detects a breakage of an optical fiber in a laser processing device in real time and prevents a disaster from occurring.

〔従来技術〕[Prior art]

従来、光ファイバは光通信分野を中心に発展してきた。 Conventionally, optical fibers have been developed mainly in the field of optical communications.

光通信分野で用いられるレーザ光は加工用レーザ光と比
較して低出力であり、光ファイバが破断してもレーザ光
の漏れ光が被膜などを加熱し着火するなどの災害に結び
つくことはない。ところが加工用の高出力レーザ光を用
いる場合には光ファイバの破断が災害を誘発する恐れが
あるので、破断を検知して災害を未然に防ぐ安全装置が
必要となる。
Laser light used in the optical communications field has a lower output than processing laser light, so even if the optical fiber breaks, the laser light leakage will not heat the coating and cause a fire, which will lead to disasters. . However, when using a high-power laser beam for processing, there is a risk that a break in the optical fiber may cause a disaster, so a safety device is required to detect the break and prevent a disaster from occurring.

公開特許公報 昭55−59788 に可撓性導光路を
もちいたレーザ装置の安全装置が挙げられている。
Japanese Patent Publication No. 55-59788 discloses a safety device for a laser device using a flexible light guide.

射出されたレーザ光の出力と加工物の表面からの反射レ
ーザ光の出力を比較することにより、レーザ光を伝送す
る可撓性導光路の異常を検知する装置である。この装置
では2つの検出器を必要とするなど回路が複雑になる上
、加工物表面からの反射光のレベルは表面の状態によっ
て大きく変動するので誤動作をひき起こしかねない。
This device detects abnormalities in the flexible light guide that transmits laser light by comparing the output of the emitted laser light and the output of the laser light reflected from the surface of the workpiece. This device requires two detectors, which makes the circuit complicated, and the level of reflected light from the workpiece surface varies greatly depending on the surface condition, which can lead to malfunctions.

また、光産業技術振興協会が昭和58年3月に発行した
1°光技術応用システムのフィーシビリテイ調査報告書
■−エネルギ伝送−”127ページには高出力レーザの
エネルギー伝送用光ファイバの破断検知方法に関して、
「破断部の漏光やケーブルの発熱を直接検出する方式、
もしくはケーブルの出力端で・−・)光の出力レベルの
低下から間接的に異常を検出する方式などが考えられよ
う」、「入出力の相対比較をおこなって異常を検出する
ことになろう」と記述されている。ところが破断部の漏
光やケーブルの発熱を直接検出する方法は、ファイバの
長さか長くなるほど検出箇所が増すので、決して実用的
とはいえない。また、レーザ光の出力レベルの低下を検
出する方法は常にレーザ光の発振状態を監視する必要か
おこる。さらにレーザ光が連続して発振され、かつ低出
力の場合には、迷光や温度の影響を受けやすくなって、
検出器が誤動作する恐れがある。また、入出力の相対比
較をおこン〒って異常を検出する方式は、上記の公開特
許公報 昭55−59788 の装置と同様に2つの検
出回路を必要とするなど装置か複雑になる。
In addition, the 1° Optical Technology Application System Feasibility Investigation Report ■ - Energy Transmission - published by the Photonics Industry and Technology Promotion Association in March 1980, page 127, describes a method for detecting breakage in optical fibers for energy transmission of high-power lasers. Regarding,
``A method that directly detects light leakage at breaks and heat generation in cables,''
Alternatively, a method of indirectly detecting an abnormality from a drop in the optical output level (at the output end of the cable...) could be considered.'', ``Anomalies would be detected by making a relative comparison of input and output.'' It is described as follows. However, the method of directly detecting light leakage at a fractured part or heat generation in a cable cannot be said to be practical because the number of detection points increases as the length of the fiber increases. Furthermore, the method for detecting a decrease in the output level of the laser beam requires constantly monitoring the oscillation state of the laser beam. Furthermore, if the laser beam is continuously oscillated and has a low output, it becomes susceptible to stray light and temperature.
The detector may malfunction. Further, the method of detecting an abnormality by performing a relative comparison of input and output requires two detection circuits, similar to the device disclosed in the above-mentioned Japanese Patent Publication No. 55-59788, making the device complicated.

〔発明の目的〕[Purpose of the invention]

本発明の目的は上記の欠点を除去し、簡単な検出装置に
よって常時光ファイバを監視し、光ファイバの破断事故
を検出すると加工用レーザ光の発振を止める光フアイバ
破断事故監視装置を提供することにある。
SUMMARY OF THE INVENTION An object of the present invention is to provide an optical fiber breakage monitoring device that eliminates the above-mentioned drawbacks, constantly monitors an optical fiber using a simple detection device, and stops oscillation of a processing laser beam when an optical fiber breakage is detected. It is in.

〔発明の構成〕[Structure of the invention]

本発明に係る光フアイバ破断事故監視装置(1、第1の
レーザ光を伝送する光ファイバと、前記第1のレーザ光
と同一の光路を有する第2のレーザ光の発振手段と、前
記第2のレーザ光を変調する手段と、前記光フアイバ出
力側に配された光学系で反射した前記第2のレーザ光の
出力レベルを検出する手段とを備えており、前記検出手
段によって’R7J記第2のレーザ光に対する前記光フ
ァイバの透過状態を常時監視し、前記光ファイバか破断
したと判断したとぎには前記第1のレーザ光の発振を停
止するように構成されたことを特徴とする。
Optical fiber breakage accident monitoring device according to the present invention (1. an optical fiber for transmitting a first laser beam; a second laser beam oscillation means having the same optical path as the first laser beam; means for modulating the second laser beam, and means for detecting the output level of the second laser beam reflected by the optical system disposed on the output side of the optical fiber, and the detecting means modulates the output level of the second laser beam. The transmission state of the optical fiber for the second laser beam is constantly monitored, and the oscillation of the first laser beam is stopped when it is determined that the optical fiber is broken.

〔実施例〕〔Example〕

本発明の一実施例に係る光フアイバ破断事故監視装置は
光フアイバ破断検出装置と安全装置から構成されている
。第1図は実施例における光フアイバ破断検出装置の構
成を示すブロック図である。
An optical fiber breakage accident monitoring device according to an embodiment of the present invention includes an optical fiber breakage detection device and a safety device. FIG. 1 is a block diagram showing the configuration of an optical fiber breakage detection device in an embodiment.

1は加工に用いられる高出力のYAGレーザ発振装fF
(,2Ll’、 Y A Oレーザ1内の全反射ミラー
である。3は一定の回転数を持っモータでその回転軸に
羽4が取りつけてあり、H’e−Nθレーザ発振装置5
か′・射出された監視用のレーザ光が羽4の回転によっ
て変調される。そして変調されたJie−Neレーザ光
は折り返しミラー6により屈曲して全反射ミラー2の裏
面に入射しYAGレーザ光の光路に重なる。ところで、
YAGレーザ装W1の共振器内に設けられたシャック7
を、YAGレーザ光に苅して(・、↓不透IJでl1e
−Neレーザ光には透明な光学部品から作るものとする
と、1(e Neレーザ光(・よYAGレーザ装置1の
発振状態にかかわらず、′活RYAGレーザ装WI?!
:通り抜けてレンズ8により光ファイバ9に入射する。
1 is a high-power YAG laser oscillator fF used for processing
(, 2Ll', is a total reflection mirror in the YAO laser 1. 3 is a motor with a constant rotation speed, and a blade 4 is attached to its rotating shaft.
-The emitted monitoring laser light is modulated by the rotation of the blades 4. The modulated Jie-Ne laser beam is bent by the folding mirror 6, enters the back surface of the total reflection mirror 2, and overlaps the optical path of the YAG laser beam. by the way,
Shack 7 provided in the resonator of the YAG laser device W1
, by exposing it to YAG laser light (・, ↓ L1e with opaque IJ
Assuming that the -Ne laser beam is made from transparent optical components, 1 (e Ne laser beam (...) Regardless of the oscillation state of the YAG laser device 1, 'Active RYAG laser device WI?!
: Passes through and enters the optical fiber 9 through the lens 8.

さらに光ファイバ9によって伝送されたHe−Neレー
ザ光は、出射側レンズ10の表面に入射し、透過光と反
射光に分かれる。そして、この反射光が光学的フィルタ
11を通り、検出器12に入射する。なお、光学的フィ
ルタ11はHe−Neレーザ光の波長(0,6328p
m )付近の光のみを透過する。
Further, the He-Ne laser beam transmitted through the optical fiber 9 enters the surface of the exit lens 10 and is separated into transmitted light and reflected light. Then, this reflected light passes through the optical filter 11 and enters the detector 12. Note that the optical filter 11 has a wavelength of He-Ne laser light (0,6328p).
m) Transmits only nearby light.

第2図は実施例における安全装置の構成ブロック図であ
る。さて、羽4によりすでに変調されたTie −Ne
レーザ光は検出器12に入射して電気信号に変換され、
この丁l気信号かコンデンサ13及び増幅器14によっ
て交流増幅された後、バンドパスフィルタ15.積分器
16を介して比較器エフに入力する。
FIG. 2 is a block diagram of the configuration of the safety device in the embodiment. Now, Tie-Ne already modulated by wing 4
The laser beam enters the detector 12 and is converted into an electrical signal,
After this signal is AC amplified by a capacitor 13 and an amplifier 14, it is filtered by a bandpass filter 15. It is input to comparator F via integrator 16.

そして、比較器17は人力信号のレベルかある一定値以
上のときにはローレベルの出力信号を、一定値以下のと
きにはハイレベルの出力信号を出力する。ところで、シ
ャッタ7か開いたときのみハイレベルとなるシャッタ駆
動信号がシャッタ7から出力されており、このンヤッタ
駆動信号と比較器17の出力信号との論理積をゲート回
路18でとる。
The comparator 17 outputs a low level output signal when the level of the human input signal is above a certain value, and outputs a high level output signal when it is below a certain value. By the way, a shutter drive signal that becomes high level only when the shutter 7 is open is outputted from the shutter 7, and a gate circuit 18 performs an AND operation between this Nyatta drive signal and the output signal of the comparator 17.

従って、シャッタ駆動信号及び比較器17の出力信号が
ともにハイレベルのときのみゲート回路18はハイレベ
ルの信号を出力する。すなわち、YAGレーザ装置1が
発振し、かつ光ファイバにより伝送されたHe−Neレ
ーザ光の出力レベルが一定値より小さいときのみ、光フ
ァイバが破断して危険であると判断してゲート回路18
からハイレベルの信号が出力される。そしてこのハイレ
ベルの出力信号を用いてシャッタ7を閉じることにより
、YAGレーザの発振を停止し、光フアイバ破断時の二
次災害を防1Fすることができる。
Therefore, the gate circuit 18 outputs a high level signal only when the shutter drive signal and the output signal of the comparator 17 are both high level. That is, only when the YAG laser device 1 oscillates and the output level of the He-Ne laser beam transmitted through the optical fiber is lower than a certain value, it is determined that the optical fiber is dangerous due to breakage and the gate circuit 18 is activated.
A high level signal is output from. By using this high-level output signal to close the shutter 7, the oscillation of the YAG laser is stopped, and a secondary disaster when the optical fiber breaks can be prevented.

このように加工用レーザ光とは異な7′、)波長をもつ
第2のレーザ光を変調して加工用レーザ光の導光路内を
伝送させ、レンズ10の表面の反射光を検出する方法を
採用しているので、加工用レーザ光の出力レベルや加工
物の表面の状態、及び迷光。
In this way, a method is proposed in which the second laser beam having a wavelength of 7') different from that of the processing laser beam is transmitted through the light guide path of the processing laser beam, and the reflected light from the surface of the lens 10 is detected. The output level of the processing laser beam, the surface condition of the workpiece, and stray light.

温度などに影響されずに常時光ファイバを監視すること
かできる。ざらに特別な監視用導光路を必要とせず、か
つレーザ光の検出器も一つで済むので装置は小型で簡素
なものとなる。
Optical fibers can be constantly monitored without being affected by temperature or other factors. Since no special monitoring light guide path is required and only one laser beam detector is required, the device is small and simple.

なお、上記実施例においては監視用レーザ光としてi’
Je −Neレーザ光を用いたか、半導体レーザなどの
他の光源でもよい。ただし、光路の重ね合わせの調整の
点及び案内光としても使用可能な点から可視光が望まし
い。また、監視用レーザ光の変調方法としては外部チョ
ッパーによる変調方式を用いたが、監視用レーザ装置の
駆動電流を変化させる内部変調式を用いてもよいのは明
白である。
In the above embodiment, i' is used as the monitoring laser beam.
A Je-Ne laser beam may be used, or other light sources such as a semiconductor laser may be used. However, visible light is preferable from the viewpoint of adjusting the overlapping of optical paths and from the viewpoint of being usable as guide light. Moreover, although a modulation method using an external chopper was used as a method of modulating the monitoring laser beam, it is obvious that an internal modulation method that changes the drive current of the monitoring laser device may be used.

ざらにCO,レーザ光(10,6μm)を伝送する光導
波〔発明の効果〕 以上説明したように本発明にUれば、加工用レーザの出
力レベル、加工物表面の状態、迷光。
Optical waveguide that roughly transmits CO and laser light (10.6 μm) [Effects of the invention] As explained above, the present invention has the following advantages: the output level of the processing laser, the condition of the surface of the workpiece, and stray light.

温度などの諸条件に影響されずに光ファイバの破断事故
を検出して、レーザの発振を停止することができる。従
って、加工用高出力レーザ光を光ファイバで伝送するレ
ーザ加工装置の安全性を増し、二次的災害を防止するこ
とが可能となる。
It is possible to detect an optical fiber breakage accident and stop laser oscillation without being affected by various conditions such as temperature. Therefore, it is possible to increase the safety of a laser processing device that transmits a high-power laser beam for processing through an optical fiber, and to prevent secondary disasters.

【図面の簡単な説明】[Brief explanation of drawings]

第1図は本発明の一実施例に係る光フアイバ破断事故監
視装置における光フアイバ破断検出装置の構成ブロック
図、第2図は実施例における安全装置の構成ブロック図
である。 1・・・YAGレーザ発振装置、2・・・全反射ミラー
。 3・・・モータ、4・−・He −Noレーザ光変調用
羽。 5I・・監視用He −Neレーザ発振装置。 6吻・−折り返しミラー、7・・−シャッタ、8・・・
レンズ。 9拳・e光ファイバ、10−a#出射側レンズ。 11・・・光学的フィルタ、12・・・検出器。 13・・lコンデンサ、14・暢・増幅器。 15・・・バンドパスフィルタ、16・・4tl 分器
。 17・・・比較器、18−・・ゲート回路。 z 第1図 8 第2図
FIG. 1 is a block diagram of the configuration of an optical fiber breakage detection device in an optical fiber breakage accident monitoring device according to an embodiment of the present invention, and FIG. 2 is a block diagram of the configuration of a safety device in the embodiment. 1... YAG laser oscillation device, 2... Total reflection mirror. 3...Motor, 4...He-No laser beam modulation blade. 5I...He-Ne laser oscillation device for monitoring. 6. - Mirror, 7. - Shutter, 8.
lens. 9-fist/e optical fiber, 10-a# output side lens. 11... Optical filter, 12... Detector. 13.L capacitor, 14.Long amplifier. 15...Band pass filter, 16...4tl divider. 17... Comparator, 18-... Gate circuit. z Figure 1 8 Figure 2

Claims (1)

【特許請求の範囲】 第1のレーザ光を伝送する光ファイバと、前記第1のレ
ーザ光と同一の光路を有する第2のレーザ光の発振手段
と、前記第2のレーザ光を変調する手段と、前記光フア
イバ出力側に配された光学系で反射した前記第2のレー
ザ光の出力レベルを検出する手段とを備えた光フアイバ
破断事故監視装置において、 前記検出手段によって前記第2のレーザ光に対する前記
光ファイバの透過状態を常時監視し、前記光ファイバが
破断したと判断したときに・1前記第1のレーザ光の発
振を停止するように構成されたことを特徴とする光フア
イバ破断事故監視装置。
[Scope of Claims] An optical fiber for transmitting a first laser beam, a second laser beam oscillation means having the same optical path as the first laser beam, and a means for modulating the second laser beam. and means for detecting an output level of the second laser beam reflected by an optical system disposed on the output side of the optical fiber, wherein the detection means detects the output level of the second laser beam. Optical fiber breakage characterized in that the transmission state of the optical fiber with respect to light is constantly monitored, and when it is determined that the optical fiber is broken, the oscillation of the first laser beam is stopped. Accident monitoring device.
JP11959184A 1984-06-11 1984-06-11 Monitor device for optical fiber break accident Pending JPS60263827A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP11959184A JPS60263827A (en) 1984-06-11 1984-06-11 Monitor device for optical fiber break accident

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP11959184A JPS60263827A (en) 1984-06-11 1984-06-11 Monitor device for optical fiber break accident

Publications (1)

Publication Number Publication Date
JPS60263827A true JPS60263827A (en) 1985-12-27

Family

ID=14765163

Family Applications (1)

Application Number Title Priority Date Filing Date
JP11959184A Pending JPS60263827A (en) 1984-06-11 1984-06-11 Monitor device for optical fiber break accident

Country Status (1)

Country Link
JP (1) JPS60263827A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH02293638A (en) * 1989-04-13 1990-12-04 General Electric Co <Ge> Optical fiber safety device
WO2019059249A1 (en) * 2017-09-21 2019-03-28 パナソニックIpマネジメント株式会社 Fault detection device, laser machining system and fault detection method

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH02293638A (en) * 1989-04-13 1990-12-04 General Electric Co <Ge> Optical fiber safety device
WO2019059249A1 (en) * 2017-09-21 2019-03-28 パナソニックIpマネジメント株式会社 Fault detection device, laser machining system and fault detection method
CN111164404A (en) * 2017-09-21 2020-05-15 松下知识产权经营株式会社 Fault detection device, laser processing system, and fault detection method
JPWO2019059249A1 (en) * 2017-09-21 2020-11-05 パナソニックIpマネジメント株式会社 Failure detection device, laser machining system and failure detection method
CN111164404B (en) * 2017-09-21 2022-05-17 松下知识产权经营株式会社 Fault detection device, laser processing system, and fault detection method

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