JPS63260690A - Laser beam machine - Google Patents

Abstract

PURPOSE:To simplify the running operation of the titled laser beam machine by providing a detector for a sound generated at the time of heat working and arranging a Q switch frequency detector and an excitation intensity detector to detect the abnormality via a binary signal of a signal level comparator. CONSTITUTION:The sound detector 9 to detect the sound 10 generated at the time of performing the laser beam machining on a work 7 is provided and the Q switch frequency detector 11 and the excitation intensity detector 13 are set up on a laser beam oscillator 1. A sound signal 9a of the detector 9 and a frequency signal 11a of the detector 11 are inputted to a band pass filter 12 and its output signal is compared with an excitation intensity signal 13a by the signal level comparator 14 and inputted to a gate circuit as the binary signal 14a. By this method, a laser machining state is always monitored based on the sound signal 9a and the abnormality of the laser beam machining is automatically detected by the binary signal 14a. Accordingly, the running operation of the laser beam oscillator 1 is simplified.

Description

[Detailed Description of the Invention] [Industrial Application Field] Is the present invention a Q-switch? It is possible to automatically detect abnormal conditions during thermal processing in the laser processing equipment 1%, which performs thermal processing using the equipped laser emission device, which simplifies operation and operation. Regarding equipment.

[Conventional technology]

Generally, thermal processing such as welding, cutting, and marking using laser light is performed by emitting a gigantic pulse laser with a high peak output from an elaser oscillator using a Q switch.
Due to the many advantages of laser light, apparatuses for performing such thermal processing have conventionally been configured to perform the above-mentioned thermal processing automatically and at high speed. For this reason, in such laser processing equipment, if the energy of the laser beam emitted from the laser oscillator becomes small, or the laser source from the laser oscillator stops emitting, or an abnormality such as a stone occurs, , it is necessary to detect this abnormal condition as soon as possible and take appropriate measures.

[Problem that the invention seeks to solve]

As mentioned above, it is necessary to constantly monitor the status of the emitted laser beam and confirm the presence or absence of abnormalities in laser processing equipment (VC), but conventional laser processing equipment VC has an automatic system that can detect this abnormality. Since no mechanism is provided, when processing with such a laser processing device, the operator must continuously monitor the processing status visually.For this reason, the conventional laser processing device VC requires only one operating operation. ″−−
This poses a problem of inconvenience.

An object of the present invention is to eliminate the need for the operator to visually monitor the machining state; 1. The purpose is simply to operate the laser processing equipment.

[Means for solving the problem] In order to solve the above-mentioned interpupil point, according to the present invention, a laser pulse is emitted from the racer excavator by a Q switch, and the laser pulse is used to strike the workpiece. In a device that performs thermal processing, there is an acoustic detector that detects the sound generated in the workpiece during heat processing and outputs an acoustic signal according to the detection result, and a switch operation frequency of the Q switch. a Q-switch frequency detector that detects and outputs a frequency signal according to the detection result of the machine; and a signal component of a frequency band according to the frequency signal included in the acoustic signal, into which the acoustic signal and the frequency signal are input. an excitation intensity detector that detects the excitation intensity that excites the laser medium of the laser oscillator and outputs an excitation intensity signal according to the detection result; and a signal level comparator that receives an excitation intensity signal, compares the level of the meat input signal, and outputs a binary signal according to the comparison result. shall do so.

[Effect]

With the above configuration, the state of laser processing is constantly monitored by the acoustic detector in degrees Celsius, and when an abnormality occurs in the laser processing, the binary signal output from the signal level comparator is set to a value corresponding to the abnormality ( Become.

Therefore, if this binary signal is automatically displayed,
During laser processing, there is no need for the operator to continuously monitor the processing status visually.C. The operation of the laser processing device becomes easier.

〔Example〕

FIG. 1 is a block diagram of an embodiment of the present invention. In the figure, l denotes a mechanical sharada 2, a Q switch 3, and a laser medium excitation device 4, which opens and closes the optical path of the laser beam that provides laser support to start and stop laser excavation.
5 is a condensing lens that focuses the laser pulse 6 emitted from the oscillator 1 onto the workpiece 7, and 8 is a conveyor that transports the workpiece 7. 9 detects the sound 10 generated at °C due to the melting of the workpiece 7 when the workpiece 7 is thermally processed by the laser pulse 6; This is an acoustic detector that outputs a signal 9a, and this detector 9 is composed of a detection section 91 and an amplification section 92. A Q-switch frequency detector detects the frequency F of the operation of one switch 3 for each of the illustrated driving parts of the switch that constitutes the Q-switch 3, and outputs a frequency signal 11a according to the detection result; Reference numeral 12 denotes a bandpass filter to which the acoustic signal 9a is input and which outputs an output signal 12a'. There is. That is, the filter 12 receives the signals 9a and lla and passes signal components in a frequency band corresponding to the signal 11a, which is included in the signal 9aVc.

Reference numeral 13 denotes an excitation intensity detector which detects the excitation intensity for exciting the laser medium of the laser medium excitation device 4VC and the two laser oscillators l, and outputs an excitation intensity signal 13a according to the detection result of the device. For example, when the laser medium of one oscillator is a Nd:YAG rod, the laser medium excitation device 4 and the construction 7
This is a detector that detects the electric power P15 applied to the lash lamp. The detector 131 is then configured to output an excitation intensity signal 13a having a level vp proportional to the electric power P added to the excitation device 4, for example. 14
are the output signal 12a of the filter 12 and the excitation intensity signal 13a
is input, and when the level of the signal 12a exceeds the level Vp of the signal 13a, it becomes H level and outputs a binary signal 14aY, and the signal 148 is the control signal 16.
It is input to a gate circuit 15 which blocks the passage of the signal 14a when the signal a is not inputted, and allows the passage of the signal 14a when the control signal 16a is inputted. control signal te
a is a signal output by the control unit 16, and this signal t6a is input to the mechanical shutter 2 and the carrier 8, and when the shutter 2) child signal 16a is input, the oscillator IK laser oscillation is started. There is. Further, the conveyor 8 receives the signal 16.
A should be entered.

It is configured to transport the workpiece 7 to a predetermined position and stop it. In Fig. 1, when the power source of this laser processing equipment is turned on, the laser medium excitation device [4] starts and continuously excites the laser medium (not shown) with a predetermined excitation intensity, and then The switch 3 is configured to perform a switching operation at a predetermined frequency F by the above-mentioned actuating section, but at this time, the control section 16 has not yet outputted the control signal tt'sa, so the laser oscillator 1 The state is such that the laser pulse 6 is not emitted.

In FIG. 1, since each part of C in FIG. Let's output fia,
First, the conveyor 8 transports the workpiece 7 to a predetermined processing position VC, and then the shutter 2 opens the optical path of the laser beam, so the laser pulse 6 is emitted from the laser oscillator l and thermal processing is not performed on the workpiece 7 at ℃. . At this time, one circuit of the gate circuit 15 becomes open. Then, the sound 10t-L emitted from the workpiece 7 when thermal processing is performed by the laser pulse 6 has a repetition frequency equal to the switch operating frequency tj, F of the Q switch 3, and the intensity of the laser pulse 6 Liquid loud sound pressure depending on the situation? It is clear that you have it. However, the intensity of the laser pulse 6 in this case corresponds to the excitation intensity Pic of the laser medium (not shown) of the laser medium excitation device 4. The acoustic signal 9a obtained when the laser pulse 6 is normally emitted from the laser oscillator l and the workpiece 7 is thermally processed normally has a signal component of one frequency F. The highest level of the signal 9a is equal to or higher than the level Vp corresponding to the excitation intensity Pvc described above. By the way, as mentioned above, the first
In the figure, the filter 12 is configured to have the filter 12vc frequency. However, even if the input signal 9aK noise is included, the signal 121 output from the Que filter 12 exhibits a unique signal waveform representing the fact that the laser pulse 6 is certainly emitted from the oscillator 1 and is colored in degrees Celsius. . When the heat processing by pulse 6 is performed normally, VC outputs the output signal 12 as described above.
When the highest level of a becomes higher than vp, at this time the comparator 14 has level Vp [@L3a is input, so the ratio! ! An H level signal 14a is output from the second device 14.
In this case, since the gate circuit 15 is brought into the open state by the child signal 16a, the output signal 15at''! of the gate circuit becomes H level.

However, in FIG. 1, if an abnormality occurs in the laser oscillator l, such as a decrease in the intensity of the laser pulse 6, the level of the acoustic signal 9a will fall below Vp, and as a result, the signal 14a* This means that the phenomenon in which 15a becomes H level does not occur. Further, even if the pulse 6 is no longer output from the oscillator 1 in FIG. 1, the signal 14a* 158 similarly continues to be at the L level. Therefore, in this laser processing device, signals 14al 15a
The occurrence of machining abnormalities can be automatically detected based on the level of processing. According to this abnormality detection method, the filter 12 is provided.

Even if there is a noise similar to the switch operation of the Q switch 3 in the acoustic signal 9a, the laser processing abnormality can be detected reliably. The gate circuit 15 is also provided to prevent malfunction of abnormality detection due to noise.The laser processing apparatus shown in FIG. 1 operates as described above, so the signal 14n or signal 15aY is automatically displayed. By keeping it in place, it becomes unnecessary for the operator to continuously monitor the machining status visually during laser machining.
Operation of such a laser processing device is extremely simple.

In FIG. 1, C indicates that the oscillator 1 continues to emit pulses 6 while - number of workpieces 7 are placed at a predetermined processing location;
The gate circuit 15 was assumed to continue to be in an open state, but 1
In the present invention, the VC control signal 1fia is configured so that the shutter 2 and the gate circuit 15 interlock to perform intermittent operation after one workpiece 7 is transported from the transporter 8vc to a predetermined processing location. In this way, it is advantageous to be able to automatically detect missing markings when marking is performed using pulse 6 after IC-j.

〔Effect of the invention〕

As mentioned above, in the present invention, C emits a laser pulse from a laser oscillator using a Q switch, and
Smell when heat processing is performed on the workpiece using thermal pulses "C1" Sound generated in the workpiece during heat processing in °C V
and an acoustic detector that detects the frequency of the switch operation of the Q switch and outputs an acoustic signal according to the detection result. A Q-switch frequency detector to output, a bandpass filter to which an acoustic signal and a frequency signal are input and pass signal components in a frequency band corresponding to the frequency signal included in the acoustic signal, and a laser medium of a laser oscillator to be excited. An excitation intensity detector detects the excitation intensity and outputs an excitation intensity signal according to the detection result, and the output signal of the bandpass filter and the excitation intensity signal are inputted, and the level of the meat input signal is compared and the comparison result is calculated. and a signal level comparator that outputs a binary signal according to the above, and an abnormality in thermal processing is detected using the binary signal.

Therefore, with the above configuration, the state of the laser processing is constantly monitored by the acoustic detector, and when an abnormality occurs in the 1MJ laser processing, the signal level comparator outputs a binary signal with a value corresponding to the abnormality. . By automatically displaying this binary signal on the IC, it is possible to use it during laser processing.

The present invention has the effect of simplifying the operation and operation of the laser processing apparatus by eliminating the need for the driver to continuously monitor the sluggish state visually.

[Brief explanation of drawings]

FIG. 1 is a block diagram of an embodiment of the present invention. 1...Laser stimulator, 3...Q switch, 6...Laser pulse, 7...
Workpiece, 9...Acoustic 13a...Excitation intensity signal, 14...Signal level comparator, 1
4a... Binary signal. Notebook 1 Diagram

Claims (1)

[Claims] In a device that emits a laser pulse from a laser oscillator using a Q switch and performs thermal processing on the workpiece using the laser pulse, detects the sound generated in the workpiece during the thermal processing and responds to the detection result. a Q-switch frequency detector that detects the frequency of switching operation of the Q-switch and outputs a frequency signal according to the detection result; a bandpass filter that passes signal components in a frequency band corresponding to the frequency signal input and included in the acoustic signal; and a bandpass filter that detects an excitation intensity for exciting a laser medium of the laser oscillator and an excitation intensity that corresponds to the detection result. an excitation intensity detector that outputs a signal; and a signal level comparison that receives the output signal of the bandpass filter and the excitation intensity signal, compares the levels of both input signals, and outputs a binary signal according to the comparison result. What is claimed is: 1. A laser processing device comprising: a device for detecting an abnormality in the thermal processing based on the binary signal.