JP2009248155A - Laser beam machining method and apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enhance laser beam machining capability by improving data efficiency, repeating speed and accuracy in the waveform control of laser power. <P>SOLUTION: The laser beam machining apparatus includes a fiber laser oscillator 10, a laser power source 12, a laser incidence section 14, a fiber transmission system 15, a laser radiating section 16, a controller 18, a touch panel 20, etc. The controller 18 in terms of hardware is composed of a CPU (micro computer), an FPGA (field programmable gate array), a digital-analog (D/A) converter, an analog-digital (A/D) converter, etc. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a laser processing technique for performing desired laser processing by irradiating a workpiece with pulsed or continuous wave laser light, and in particular, a laser processing method and laser processing for controlling the waveform of laser beam output (power). Relates to the device.

  In general, a technique for controlling the waveform of the output of laser light in laser processing is often used in laser welding. For example, in laser spot welding, each welding point of a workpiece is irradiated with pulsed laser light in a single shot or in a continuous manner. Further, in laser seam welding, a pulsed laser beam is irradiated on a workpiece welding line with overlap scanning at a constant repetition frequency, or a continuous wave (CW) laser beam is irradiated with continuous scanning. In such laser welding processing, it is possible to adjust the degree of penetration, the degree of finish, etc. by arbitrarily changing the waveform of the laser power.

  For example, Patent Document 1 discloses a fiber laser processing in which a reference waveform is output from a control board (control unit), and a laser power source unit drives a laser excitation unit in response to this, and laser light having a desired waveform shape is oscillated and output. A machine is disclosed. Furthermore, this fiber laser processing machine discloses that the output of a processing laser beam is monitored and fed back to a laser power source unit.

  A conventional laser welding apparatus performs laser power waveform control by using a memory writing / reading function of a CPU (microcomputer). That is, when a user inputs a desired reference waveform through a man-machine interface such as a touch panel, the CPU encodes the set and input reference waveform at a predetermined sampling period and stores the binary code as reference waveform data. Write to. Then, when executing laser welding, the CPU reads the reference waveform data from the memory at time intervals of the sampling period, and reproduces the digital reference waveform signal. The digital reference waveform signal reproduced by the memory reading function of the CPU is converted into an analog reference waveform signal by the D / A converter, and the analog reference waveform signal is used as a control signal for the laser power supply unit. Typically, it is supplied to an output (power) of a processing laser beam oscillated and output from a laser oscillator, or to an excitation light source such as a laser diode (LD) for optically exciting an active medium in the optical resonator. Feedback control is applied so that the drive current or the like follows the analog reference waveform signal.

However, even if feedback control is applied in the waveform control of the laser power, the actual value of the monitoring target (laser output, LD drive current, etc.) does not always follow the reference waveform accurately. In the conventional laser welding apparatus, when checking whether the error of the waveform to be monitored with respect to the reference waveform is within a predetermined allowable range (good / bad determination), all necessary calculation processing is performed by the CPU. .
JP2007-190566

  However, the conventional technology that uses the CPU's memory write / read function and arithmetic processing function exclusively for the laser power waveform control as described above takes too much time for signal processing and meets the required specifications for today's precision welding processing. Insufficient response is a problem.

  Specifically, when the reference waveform is reproduced, the CPU takes a long time to read the reference waveform data from the memory, and the reference waveform is reproduced with a sampling period of 50 μsec or more at the shortest.

  In addition, when a function for determining the quality of waveform control is installed, if the waveform integration calculation process for quality determination is performed simultaneously or in parallel with the reference waveform reproduction process, the load on the CPU further increases, and waveform control is performed. The speed is reduced. Therefore, after the one-pulse waveform control is completed, the CPU performs the waveform integration calculation process and the determination calculation process for each of the reference waveform and the monitor waveform. However, in the repeat mode in which the pulsed laser beam is repeated a predetermined number of times, not only the time required for the waveform control of one pulse but also the time required for the pass / fail judgment calculation processing is included in one cycle. If the waveform integration calculation process is performed in the post-processing, the time (cycle) of one cycle is inevitably long. For this reason, the repetition frequency of the repeat mode is limited to 500 Hz (period 2 msec), and high speed has been strongly desired.

  On the other hand, in the continuous oscillation (CW) mode, for example, when setting a continuous waveform of several tens of seconds or more, according to the related art as described above, reference waveform data (binary code) generated from one reference waveform The amount of data becomes so large that it cannot be stored in normal memory. Therefore, in the CW mode, the sampling cycle is set to an extremely long value (for example, 50 msec) to compress the data. However, when the sampling period is extremely long as described above, the time resolution of the reference waveform set by the CPU is lowered, and as a result, the accuracy of waveform control is lowered.

  The present invention has been made in view of the problems of the prior art, and provides a laser processing method and a laser processing apparatus that improve data processing efficiency, repetition rate, and accuracy in laser power waveform control to improve laser processing capability. The purpose is to provide.

  In order to achieve the above object, a laser processing method according to the present invention includes a first step of connecting a plurality of line segment waveform elements along a time axis to set a desired reference waveform, and each of the lines For the segment waveform element, at least the initial value data representing the start value, the change rate data representing the slope, and the line segment interval time representing the length of time from the start end to the start of the following line segment waveform element A second step of generating the data of 1 as the parameter data of one stage, and reproducing the line segment waveform element by performing predetermined arithmetic processing based on the parameter data for each stage along the time axis, A third step of substantially connecting the line segment waveform elements across the stage to restore the reference waveform; and outputting the pulsed or continuous wave laser light output used for desired laser processing to the restored basis. And a fourth step of varying in accordance with the waveform.

  In the laser processing method of the present invention, the desired reference waveform is not decomposed at the setting stage along the time axis at the sampling period, but each of the multiple or stage line segment waveform elements constituting the reference waveform. A plurality of parameter data indicating predetermined attributes (initial value, inclination, line segment interval time, etc.) are generated, and information management is performed on the parameter data for each stage. And, when using the reference waveform for laser processing waveform control, along the time axis, reproduce the line segment waveform element by performing a predetermined calculation process based on the parameter data for each stage in order of the stage, The reference waveform is restored by substantially connecting the line segment waveform elements over all stages. By changing the output of the pulsed or continuous wave laser light in accordance with the restored reference waveform, desired laser processing can be performed.

  According to a preferred aspect of the present invention, in the second step, when the constant period is ΔT and the line segment interval time is N × ΔT (N is a positive integer) for each line segment waveform element, Data representing a numerical value N is generated as data representing the line segment interval time. In a third step, a change amount for a fixed period ΔT is obtained from the change rate, and the change amount for a fixed period is sequentially determined from the initial value as N. The line segment waveform element is reproduced by adding back.

  The waveform generation period ΔT may be set to a common value (fixed value) over all line segment waveform elements, but may be determined according to the rate of change for each line segment waveform element. In that case, it is preferable that ΔT is shortened as the change rate of the line segment waveform element is increased, and ΔT is increased as the change rate of the line segment waveform element is decreased. That is, when the change rate is large, the calculation processing time is shortened, and when the change rate is small, the calculation processing time is lengthened, so that both the accuracy of waveform reproduction and the calculation processing efficiency can be achieved.

  According to a preferred aspect, the method further includes a fifth step of setting at least a desired wave height reference value as one of the parameters of the reference waveform, and the rate of change is set as the wave height in the second step and the third step. Used as a percentage of the reference value. Thus, by using the rate of change as a ratio with respect to the pulse height reference value, the reference waveform can be commonly used for both current waveform control and laser output waveform control.

  According to a preferred aspect, in the second step, flag data representing the resolution of the change rate is further generated as one of the stage parameter data, and in the third step, the resolution flag indicates The rate of change is used with high resolution. Thus, by having the function of changing the resolution with respect to the rate of change of the line segment waveform element, the accuracy of waveform reproduction can be further increased.

  A laser processing apparatus according to the present invention includes a reference waveform setting unit that sets a desired reference waveform by connecting a plurality of line segment waveform elements along a time axis, and at least the start of each line segment waveform element. Initial stage data representing a value, change rate data representing a slope, and line segment interval time data representing the length of time from the start to the start of the next line segment waveform element are used as one-stage parameter data. A stage / parameter data generation unit to be generated and a predetermined arithmetic processing based on the parameter data for each stage along the time axis to reproduce the line segment waveform element, and the line segment waveform element over all stages A reference waveform restoration unit that substantially restores the reference waveform by combining them, and an output of a pulsed or continuous wave laser beam used for desired laser processing is used as the restored reference waveform. And a laser output varying unit for varying Te.

  In the laser processing apparatus of the present invention, the reference waveform setting unit may set a desired reference waveform by connecting a plurality of line segment waveform elements along the time axis. The reference waveform is not decomposed at the sampling stage along the time axis at the setting stage. Instead, the stage / parameter data generation unit indicates a plurality of parameter data indicating predetermined attributes (initial value, slope, line segment interval time, etc.) for each of a plurality of line segment waveform elements or a plurality of stages constituting the reference waveform. Is generated. When the reference waveform is used for laser processing waveform control, the reference waveform restoration unit performs a predetermined calculation process on the basis of the parameter data for each stage in the order of the stage along the time axis, and performs line segmentation. The waveform element is reproduced, and the reference waveform is restored by substantially connecting the line segment waveform elements over all stages. The laser output variable unit varies the output of pulsed or continuous wave laser light according to the restored reference waveform, and performs laser processing by waveform control.

  In a preferred aspect of the present invention, the reference waveform setting unit and the stage parameter data generation unit are constituted by a CPU (microcomputer), and the reference waveform restoration unit is constructed in an FPGA (field programmable gate array). In this case, it is preferable that a parameter data memory for receiving and holding the parameter data related to the reference waveform from the CPU is further built in the FPGA. The parameter data of the stage is stored each time each line segment waveform element is reproduced. A buffer memory that is transferred and held from the parameter data memory may be further constructed.

  In a preferred aspect, the laser output variable unit includes an optical resonator including an active medium for oscillating and outputting laser light, an excitation light source for optically exciting the active medium, and the excitation light source. A laser power source that supplies a driving current for light emission, a current measuring unit that measures the driving current, and a control unit that controls the driving circuit so that the measured value of the driving current follows the reference waveform.

  In this case, in the FPGA, a reference waveform integration circuit that performs an integration operation on the reference waveform being restored during the period in which the laser beam is oscillated and output, and a measured value of the drive current during the period in which the laser beam is oscillated and output. The monitor waveform integration circuit that performs the integration calculation on the drive current waveform based on this, and immediately after the laser beam oscillation output is completed or interrupted, the integrated value of the reference waveform and the integrated value of the drive current waveform are compared, A pass / fail judgment circuit for judging pass / fail regarding the output of the laser beam based on the comparison error may be constructed.

  In this case, the pass / fail judgment criteria of the pass / fail judgment circuit may be set by the user (operator or the like) on an allowable range on the display. For example, what percentage should be allowed for the upper and lower limit values with respect to the integral value of the reference waveform may be set.

  Alternatively, the CPU may calculate an integral value of the waveform based on the reference waveform. Then, in the FPGA, a monitor waveform integration circuit that performs an integration operation on the waveform of the drive current based on the measured value of the drive current during the period in which the laser beam is oscillated and output, and the oscillation output of the laser beam ends, or Immediately after the interruption, a pass / fail judgment circuit that compares the integral value of the reference waveform and the integral value of the drive current waveform and judges pass / fail regarding the output of the laser beam based on the comparison error may be constructed.

  In this case, the pass / fail judgment criteria of the pass / fail judgment circuit may be set by the user (operator or the like) as a percentage as described above. Alternatively, the integral value calculated by the CPU may be displayed on the display, and based on this, the user (operator or the like) may directly input the upper and lower limit values.

  In another preferred embodiment, the laser output variable unit includes an optical resonator including an active medium for oscillating and outputting laser light, an excitation light source for optically exciting the active medium, and the excitation A laser power supply that supplies a driving current for light emission to the light source, a laser output measurement unit that measures the output of the laser light oscillated and output from the optical resonator, and a drive circuit so that the measured value of the laser output follows the reference waveform A control unit for controlling.

  In this case, in the FPGA, a reference waveform integration circuit that performs an integration operation on the reference waveform being restored during the period in which the laser beam is oscillated and output, and a measured value of the laser output during the period in which the laser beam is oscillated and output. Based on the monitor waveform integration circuit that performs the integration calculation for the laser output waveform, and immediately after the laser light oscillation output is completed or interrupted, the reference waveform integration value and the laser output waveform integration value are compared, A pass / fail judgment circuit for judging pass / fail regarding the output of the laser beam based on the comparison error may be constructed.

  Alternatively, the CPU may calculate an integral value of the waveform based on the reference waveform. Then, in the FPGA, a monitor waveform integration circuit that performs an integration calculation on the waveform of the laser output based on the measured value of the laser main power during the period in which the laser beam is oscillated and output, and the oscillation output of the laser beam is terminated, or Immediately after the interruption, a pass / fail determination circuit that compares the integrated value of the reference waveform with the integrated value of the drive current waveform and determines pass / fail regarding the output of the laser beam based on the comparison error may be constructed.

  According to the laser processing method or the laser processing apparatus of the present invention, with the above-described configuration and operation, it is possible to improve the laser processing capability by improving the data efficiency, repetition rate, and accuracy in laser power waveform control. .

  Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings.

  In FIG. 1, the structure of the laser processing apparatus in one Embodiment of this invention is shown. This laser processing apparatus is configured as a fiber laser welding machine, and includes a fiber laser oscillator 10, a laser power source 12, a laser incident unit 14, a fiber transmission system 15, a laser emitting unit 16, a control unit 18, a touch panel 20, and the like. ing.

  The fiber laser oscillator 10 includes an oscillation optical fiber (hereinafter referred to as “oscillation fiber”) 22, an electro-optical excitation unit 24 that irradiates one end surface of the oscillation fiber 22 with pumping excitation light MB, and an oscillation fiber. 22 and a pair of optical resonator mirrors 26 and 28 that are optically opposed to each other via 22.

The electro-optic excitation unit 24 includes a laser diode (LD) 30 as an excitation light source and a condensing optical lens 32. LD30 is, LD drive current (or LD excitation current) is being driven to emit light supply or inject I _D from the laser power source 12, which oscillates and outputs a LD light clogging excitation light MB having a predetermined wavelength. The optical lens 32 condenses and enters the excitation light MB from the LD 30 onto one end surface of the oscillation fiber 22. The optical resonator mirror 26 disposed between the LD 30 and the optical lens 32 transmits the excitation light MB incident from the LD 30 side, and totally reflects the oscillation light incident from the oscillation fiber 22 side on the optical axis of the resonator. Is configured to do.

To measure the LD drive current I _D supplied to the laser power supply 12 than the LD34, the current sensor 25 and the LD current measurement circuit 27 are provided. The current sensor 25 is composed of, for example, a Hall element, and detects the LD drive current _ID without contact. LD current measurement circuit 27 inputs the output signal of the current sensor 25 a current measuring value of the LD drive current I _D (eg, current effective value) is calculated M _ID. The current measurement value M _ID obtained by the LD current measurement circuit 27 is supplied to the laser power source 12 as a feedback signal and to the control unit 18 as a monitor signal.

  Although not shown, the oscillation fiber 22 has a core doped with, for example, rare earth element ions as a light emitting element, and a clad surrounding the core coaxially. The core is used as an active medium, and the clad is used as the propagation of excitation light. The light path. The excitation laser beam MB incident on one end surface of the oscillation fiber 22 as described above propagates in the oscillation fiber 22 in the axial direction while being confined by total reflection at the cladding outer peripheral interface, and the core passes several times during the propagation. Across the core, photoexcites rare earth ions in the core. In this way, an oscillating light beam having a predetermined wavelength is emitted in the axial direction from both end faces of the core, and this oscillating light beam travels back and forth between the optical resonator mirrors 26 and 28 and is resonantly amplified. A fiber laser beam FB having the predetermined wavelength is extracted from the optical resonator mirror 28.

  In the optical resonator, the optical lenses 32 and 34 collimate the oscillating light beam emitted from the end face of the oscillation fiber 22 into parallel light and pass the collimated light to the optical resonator mirrors 26 and 28. The oscillating light beam reflected and returned by is condensed on the end face of the oscillating fiber 22. The excitation laser beam MB that has passed through the oscillation fiber 22 passes through the optical lens 34 and the optical resonator mirror 28 and is then folded back toward the side laser absorber 38 by the folding mirror 36. The fiber laser light FB output from the optical resonator mirror 28 passes straight through the folding mirror 36 and then passes through the beam splitter 40 before entering the laser incident portion 14.

The beam splitter 40 reflects a small portion (for example, 1%) of the incident fiber laser light FB in a predetermined direction, that is, the power sensor photosensor (PD) 42 side, and transmits the remaining most (99%) straight. Let A condensing lens 44 that condenses the reflected light from the beam splitter 40 or the monitor light R _FB is disposed in front of the photo sensor (PD) 42.

The photosensor (PD) 42 photoelectrically converts the monitor light R _FB from the beam splitter 40 and outputs an electrical signal (laser output measurement signal) representing the laser output (power) of the fiber laser light FB. The laser output measurement circuit 45 obtains the laser output measurement value M _FB of the fiber laser light FB by analog signal processing based on the output signal of the photosensor 42. The laser output measurement value M _FB obtained by the laser output measurement circuit 45 is supplied to the laser power source 12 as a feedback signal and to the control unit 18 as a monitor signal.

  The fiber laser beam FB that passes straight through the beam splitter 40 and enters the laser incident section 14 is first folded in a predetermined direction by the vent mirror 46, and then condensed by the condenser lens 50 in the incident unit 48 and transmitted through the fiber. The light is incident on one end face of a transmission optical fiber (hereinafter referred to as “transmission fiber”) 52 of the system 15. The transmission optical fiber 52 is made of, for example, an SI (step index) fiber, and transmits the fiber laser light FB incident in the incident unit 48 to the emission unit 54 of the laser emission unit 16. The emission unit 54 includes a collimator lens 56 that collimates the fiber laser light FB emitted from the end face of the transmission fiber 52 into parallel light, and a condensing lens 58 that condenses the parallel fiber laser light FB at a predetermined focal position. have.

When the laser welding is performed, the driving current I _D that is waveform control from the laser power source 12 is supplied (injected) to the LD 30, the fiber laser oscillator 10 within at LD 30 than the driving current I _D of the LD output waveform corresponding to the waveform The pumping light MB is supplied (injected) into the oscillation fiber 22, and the fiber laser oscillator 10 oscillates and outputs the fiber laser beam FB having a laser output waveform corresponding to the LD output waveform. The waveform-controlled fiber laser beam FB is focused and irradiated on a welding point or a welding line of the workpiece W through the laser incident portion 14, the fiber transmission system 15, and the laser emitting portion 16. At the welding point or welding line, the workpiece material is melted by the energy of the fiber laser beam FB, and solidifies after the pulse irradiation to form a nugget.

  In this fiber laser welding apparatus, the fiber laser oscillator 10 uses a fiber laser beam FB having a small beam diameter and a small beam divergence angle because the oscillation fiber 22 uses an elongated core having a diameter of about 10 μm and a length of several meters as an active medium. Can be output. Moreover, since the excitation laser light MB incident on one end face of the oscillation fiber 22 propagates through the long optical path of several meters in the oscillation fiber 22 and exhausts the excitation energy many times, the oscillation efficiency is very high. Thus, the fiber laser beam FB can be generated. The fiber laser oscillator 10 has a very stable beam mode because the core of the oscillation fiber 22 does not cause a thermal lens effect. As described above, since both the beam mode and the laser output are stable, the laser oscillation in the CW mode can be sustained for a maximum of about 100 seconds.

  As will be described later, this fiber laser welding apparatus enables arbitrary and various waveform control for the output (power) of the fiber laser beam FB, and realizes a significant increase in repetition rate in the repeat mode, while in the CW mode. Waveform control accuracy (time resolution) has been greatly improved, and it is possible to freely adjust the welding penetration and finish in any welding process, which is sufficient for strict requirements for precision welding processes. We can cope with room.

  Here, FIG. 2, FIG. 3 and FIG. 4 show basic forms (modes) of reference waveforms that can be set and input in this fiber laser welding apparatus. In any mode, a desired reference waveform is set by substantially connecting a plurality of line segment waveform elements along the time axis.

FIG. 2 shows an example of a reference waveform in the single oscillation mode. For example, it is possible to set an arbitrary pulse waveform duration T _A of 0.1～500Msec. The illustrated reference waveform A is formed by connecting _three line segment waveform elements a ₁ , a ₂ , and a ₃ .

FIG. 3 shows an example of a repetitive reference waveform in the repeat mode. For example, the repetition of the reference waveform A having a duration T _A of 0.1 to 500 msec can be set over a period T _{C of a} maximum of 99 sec (the fastest repetition frequency including a quality determination operation described later: 5 kHz). .

FIG. 4 shows an example of a reference waveform in the CW mode. For example, it is possible to set an arbitrary continuous waveform duration 0.5~99sec T _B. The illustrated reference waveform B is formed by connecting seven line segment waveform elements b ₁ , b ₂ , b ₃ , b ₄ , b ₅ , b ₆ , and b ₇ .

  FIG. 5 shows a specific configuration example of the control unit 18 in this embodiment. As illustrated, the control unit 18 includes a CPU (microcomputer) 64, an FPGA (field programmable gate array) 66, a digital-analog (D / A) converter 68, an analog-digital (A) in terms of hardware. / D) converters 70 and 72 and a connecting device 74 are provided.

  The CPU 64 includes a central processing unit, a program memory, a data memory, an interface circuit, and the like, and controls the operation of the entire apparatus or each unit according to various programs (software) stored in the program memory. In particular, regarding the laser power waveform control, the CPU 64 inputs a reference waveform desired by the user (worker, maintenance worker, etc.) via the display unit 20 a and the input unit 20 b of the touch panel 20.

  In this embodiment, the CPU 64 does not sample and encode the reference waveform set and input through the touch panel 20 as it is in the prior art, but rather encodes the reference waveform on the time axis as a plurality of line segments. The data is decomposed into waveform elements, and parameter data indicating the characteristics of each line segment waveform element is generated. In this embodiment, for each line segment waveform element, that is, for each stage, (1) “initial value” data representing the starting value, (2) “change rate” data representing the slope, (3) "Line segment interval time" data indicating the length of time from the start to the start of the next line segment waveform element, and (4) "Modulation flag / resolution" indicating the user option and CPU setting scale for the modulation function and resolution, respectively. Four types of parameter data, “flag” data, are generated.

For example, taking the first line segment waveform element a ₁ of the reference waveform A of FIG. 2 as an example, as shown in FIG. 6, the “initial value” is the value of the start end q ₁ (usually 0), and “change rate” “ΔA (%) / ΔT (μsec)”, and “Line segment interval time” is N (pieces) × ΔT (μsec). Here, ΔT is not a sampling period but a period of calculation output or signal processing cycle for one time when each line segment waveform element is reproduced in the FPGA 66 as described later. Since ΔT is constant in each stage, data representing the numerical value N may be used as the “line segment section time” data.

The “modulation flag” indicates whether or not a modulation waveform H having a constant frequency as shown in FIG. 7, for example, should be superimposed when reproducing the waveform component a ₁ on the FPGA 66 side. When the modulation flag is “0”, no modulation is applied, and when the modulation flag is “1”, the modulation is applied.

The “resolution flag” indicates a scale to be used for the “change rate” when the FPGA 66 reproduces the corresponding waveform element a ₁ . For example, the resolution flag “0” indicates a scale of [0.01% −1]. Here, [0.01% -1] means a scale in which [0.01%] is “1”. That is, when the ratio J of the unit change amount ΔA to the wave height reference value is 0.01% in percentage display, the “change rate” ΔS (ΔS = ΔA / ΔT) is 1. Therefore, ΔS = 10 when J = 0.10%, and ΔS = 100 when J = 1.0%. On the other hand, the resolution flag “1” indicates a scale of [0.00001% −1]. That is, when the ratio J of the unit change amount ΔA to the wave height reference value is 0.00001% in percentage display, the “change rate” ΔS is 1. Therefore, ΔS = 10 when J = 0.0001%, and ΔS = 100 when J = 0.001%.

For example, as shown in FIG. 8, when the slope (change rate) of the line segment waveform element a ₁ is normal or higher, a scale of [0.01% -1] is used, and the slope (change rate) is considerably small. Sometimes a scale of [0.00001% -1] is used.

  The CPU 64 manages the above four types of parameter data for one stage generated for each line segment waveform element in a set as shown in FIG. 9, for example.

  Further, the CPU 64 also generates basic parameter data of the entire reference waveform in a format as shown in FIG. 10, for example. Here, the “wave height reference value” corresponds to the denominator of “change rate” which is one of the stage parameters, and can be freely set by the user. For example, if the user sets the “wave height reference value” to 200 A for the LD drive current, J = 5% when the change amount ΔA per period ΔT is 10 A in the example of FIG. In this case, the CPU 64 adopts a scale of [0.01% −1] and generates “change rate” data of S = 500.

In FIG. 10, “repetition frequency” and “number of repetitions” are the repetition frequency (m / T _C ) and the number of repetitions (m) of the reference waveform in the repeat mode (FIG. 3). May be used. “Monitoring period designation” is a parameter for designating a mode (entire waveform or every constant period) for monitoring in the CW mode (FIG. 4), and the period can be variably set. “Modulation type flag” extends the function of “Modulation flag” of the above stage parameter, and is selected by the user when multiple types of modulation waveforms such as rectangular wave, sine wave, and sawtooth wave are prepared. Give a code to identify what you did.

  The CPU 64 manages parameter data (FIG. 10) of the entire reference waveform and parameter data (FIG. 9) for each line segment waveform element (stage) for one reference waveform, for example, in the format shown in FIG. And stored in a data memory inside or outside the CPU. Although not shown, it is preferable to attach termination instruction data indicating that the nth stage is the final stage. In this embodiment, the provisional (n + 1) stage is defined, and the data N of the “segment time” is set to 0, so that the previous nth stage is the final stage. I am trying to show that.

  FIG. 12 shows an example of the configuration of various circuits built in the FPGA 66 in this embodiment. As shown, the FPGA 66 includes a data memory 80, a control circuit 82, a basic parameter data buffer memory 84, a stage parameter data buffer memory 86, a reference waveform restoration arithmetic circuit 88, a reference waveform output circuit 90, and a modulation data memory. 92, modulation data buffer 93, address counter 94, cycle counter 95, count comparison circuit 96, reference waveform integration circuit 98, current monitor waveform buffer memory 100, laser output monitor waveform buffer memory 102, current monitor waveform integration circuit 104, laser output A monitor waveform integration circuit 106, a comparison determination circuit 108, and the like are built in. A clock necessary for the operation of these circuits 80 to 108 is supplied from an external clock circuit 110.

  Prior to the start of the laser welding process, all parameter data (FIG. 11) relating to the reference waveform used in the laser welding process is written into the data memory 80 by the CPU 64. The control circuit 82 receives a required control signal and various data related to the control from the CPU 64 and controls each part in the FPGA 66.

  The basic parameter data buffer memory 84 fetches and holds the basic parameter data (FIG. 10) of the entire reference waveform from the data memory 80 when executing the restoration process of the reference waveform. The stage parameter data buffer memory 86 fetches and holds the parameter data (FIG. 9) of the stage from the data memory 80 when executing the reproduction processing of each line segment waveform element.

  Under the control of the control circuit 82, the reference waveform restoration arithmetic circuit 88 performs predetermined arithmetic processing on the basis of parameter data for each stage along the time axis to reproduce each line segment waveform element over all stages. A process of substantially connecting the line segment waveform elements to restore the reference waveform is executed by a constant period (ΔT) calculation. For this arithmetic processing, the parameter data (FIG. 10) of the entire reference waveform is received from the basic parameter data buffer memory 84, and the parameter data (FIG. 9) of each stage is overwritten in order of the stages from the stage parameter data buffer memory 86. And receives the data of the modulation waveform h (FIG. 7) from the modulation data memory 92 via the modulation buffer 93.

  The modulation data memory 92 stores a predetermined number, for example, 100 pieces of modulation data obtained by sampling the modulation waveform for one cycle at equal intervals on the time axis. The address counter 94 constitutes a DMA controller for reading modulation waveform data from the modulation data memory 92 one by one at a constant period (ΔT).

  The “line segment interval time” data in the stage parameter data is supplied not to the arithmetic circuit 88 but to the count comparison circuit 96 as described later.

  The reference waveform output circuit 90 takes in the reproduction data CS of the line segment waveform element generated at regular intervals (ΔT) from the reference waveform restoration calculation circuit 88 and controls the reproduction data CS of the line segment waveform element to the laser power source 12. A signal is output at a predetermined timing.

  The cycle counter 95 and the count comparison circuit 96 constitute a timer circuit for measuring the duration (line segment interval time) of each stage in the reference waveform restoration process. The cycle counter 95 is reset at the start of each stage, and is counted once every period (ΔT) of the restoration process, for example, every time the reproduction data CS of the line segment waveform element is output from the reference waveform restoration arithmetic circuit 88. Up and output the count value i.

  The count comparison circuit 96 compares the count value i from the cycle counter 95 with the data N of “line segment section time” held in the stage parameter data buffer memory 86, and when i reaches N, A stage end notification signal K is generated to notify that the stage has ended. When a stage end notification signal K is issued from the count comparison circuit 96, in response to this, the control circuit 82 overwrites and loads the next stage parameter data from the data memory 80 into the stage parameter data buffer memory 86. It has become.

  The reference waveform integration circuit 98 takes in and reproduces the reproduction data CS of the line segment waveform elements output at regular intervals (ΔT) from the reference waveform output circuit 90, and obtains the integrated value of the reference waveform being reproduced.

The current monitor waveform buffer memory 100 latches the LD drive current measurement value M _ID sent from the LD current measurement circuit 27 via the connection circuit 74 and the A / D converter 70 (FIG. 5). The current monitor waveform integration circuit 104 takes in the LD drive current measurement value M _ID from the current monitor waveform buffer memory 100 every predetermined period (ΔT), and accumulates and calculates the integrated value of the LD drive current monitor waveform.

The laser output monitor waveform buffer memory 102 latches the laser output measurement value M _FB sent from the laser output measurement circuit 45 via the connection circuit 74 and the A / D converter 72 (FIG. 5). The laser output monitor waveform integrator circuit 106 cumulatively adds captures the laser output measurement value M _FB to a predetermined cycle ([Delta] T) from the laser output monitor waveform buffer memory 102, obtains the integral value of the laser output monitor waveform.

  The comparison / determination circuit 108 integrates the integrated value of the reference waveform obtained by the reference waveform integration circuit 98 and the LD drive current monitor waveform obtained by the current monitor waveform integration circuit 104 every time one monitoring period ends. Or an integrated value of the laser output monitor waveform obtained by the laser output monitor waveform integrating circuit 106 to obtain a difference (error), and whether or not the error is within a predetermined allowable range. Is judged (good or bad judgment). And when the determination result of a defect comes out, this is transmitted to CPU64.

  Note that when the result of determination of failure is sent to the CPU 64, the monitor waveform data stored in the buffer memories 100 and 102 can also be sent to the CPU 64.

Although not shown, the laser power source 12 includes a DC power source, an LD drive circuit, a comparator, a feedback signal selection circuit, and the like. The DC power source is composed of, for example, an inverter circuit or a switching regulator circuit, and outputs a constant LD drive voltage. The LD drive circuit includes a V-I conversion circuit that generates an LD drive current _ID from the LD drive voltage, and is sent from the reference waveform output circuit 90 of the FPGA 66 through the D / A converter 68 and the connection circuit 74. It varies the LD drive current I _D to follow the analog reference waveform signal a _CS. The comparator inputs the analog reference waveform signal A _CS from FPGA66 as a command signal, and inputs the LD drive current measurement value M _ID or the laser output measurement value M _FB as a feedback signal from the feedback signal selection circuit, the two input signals An error signal representing the difference is output. The LD drive circuit varies the LD drive current _ID in a direction to make the error signal zero. Feedback signal selection circuit, under the control of the CPU 64, selects the LD drive current measurement value M _ID when applying feedback control for the LD drive current I _D, the feedback control for the output of the fiber laser beam FB When applying, the laser output measurement value _MFB is selected.

  FIG. 13 is a flowchart showing an overall processing procedure in the FPGA 66 in the single mode or repeat mode. This flow is started when a desired laser welding process is performed, and the entire sequence is controlled by the control circuit 82. Prior to this flow, as described above, all parameter data (FIG. 11) relating to the reference waveform used in this laser welding process is written into the data memory 80 of the FPGA 66 by the CPU 64.

First, the control circuit 82 reads out the basic parameters data of the entire reference waveform from the data memory 80 (FIG. 10), to load or set the basic parameters data buffer memory 84 (Step S _1).

Next, the control circuit 82 accesses the data memory 80, reads the “line segment section time” data N in the stage parameter data to be read next (step S ₂ ), and N> 0 and N = 0. It is inspected (step S ₃ ). Since the first stage always exists, N> 0 and is valid. Therefore, the parameter data (FIG. 9) of the stage is read from the data memory 80 and set in the stage parameter data buffer memory 86 (step S). ₄ ).

Next, the control circuit 82 causes the reference waveform restoration calculation circuit 88 to repeatedly perform a calculation process (step S ₅ ) for reproducing the line segment waveform element at a constant period (ΔT) (steps S ₅ → S ₈ → S ₉ → S ₁₀ → S ₅ ..). The reference waveform restoration calculation circuit 88 obtains a unit change amount ΔA per fixed period ΔT from the “change rate” data, the “resolution” flag, the modulation flag, and the modulation data by calculation such as addition / subtraction / division / division, etc., and “initial value” ( q) is added to the end of the line segment waveform element being reproduced, and the reproduction data CS of the line segment waveform element indicating the updated value at the end of the waveform is generated at every constant period ΔT starting from q). .

In addition, the control circuit 82 provides the reference waveform output circuit 90 with a data output process (step S ₆ ) for outputting the reproduction data CS of the line segment waveform element generated by the reference waveform restoration calculation circuit 88 to the laser power source 12. Repeatedly with a period (ΔT) (steps S ₅ → S ₆ → S ₉ → S ₁₀ → S ₆ ...). In parallel with this, the current monitor waveform buffer memory 100 and the laser output monitor waveform buffer memory 102 store the LD drive current measurement value M _ID and the laser output measurement value from the LD current measurement circuit 27 and the laser output measurement circuit 45, respectively. The monitor waveform data input process (step S ₆ ) for latching M _FB is repeatedly performed at a constant period (ΔT) (steps S ₅ → S ₆ → S ₉ → S ₁₀ → S ₆ ...).

In addition, the control circuit 82 repeatedly performs an integration operation process (step S ₇ ) for integrating the reproduction data CS of the line segment waveform element output from the reference waveform output circuit 90 on the reference waveform integration circuit 98 at a constant period (ΔT). (Steps S ₅ → S ₇ → S ₉ → S ₁₀ → S ₇ ...) In parallel with this, the current monitor waveform integration circuit 104 and the laser output monitor waveform integration circuit 106 monitor the LD drive current measurement value M _ID and the laser output measurement value M _FB that are being monitored, respectively. The process (step S ₇ ) is repeatedly performed at a constant period (ΔT) (steps S ₅ → S ₇ → S ₉ → S ₁₀ → S ₇ ...).

  As described above, the reference waveform itself is not read out from the memory at the sampling period and the reference waveform is restored, but the FPGA 66 is based on a plurality of parameter data indicating characteristics or attributes of the reference waveform or each line segment waveform element. Since this method restores the reference waveform by repeating the calculation output every fixed period (ΔT), the amount of data required for the restoration process of the reference waveform is greatly reduced (1/10 or less) compared to the conventional CPU method. be able to.

Further, a waveform reproduction calculation process (step S ₅ ) for each fixed period (ΔT) by the reference waveform restoration calculation circuit 88 as described above, a reproduction data output process for each fixed period (ΔT) by the reference waveform output circuit 90, and a current monitor. Monitor waveform data input processing (step S ₆ ) by the waveform buffer memory 100 and the laser output monitor waveform buffer memory 102, reference waveform integration calculation processing for each fixed period (ΔT) by the reference waveform integration circuit 98, current monitor waveform integration circuit 104, and The monitor waveform integration calculation process (step S ₇ ) for each fixed period (ΔT) by the laser output monitor waveform integration circuit 106 does not require a bus cycle or a large number of machine cycles in one process unlike the CPU operation. Since it is performed in a pipeline manner, the FPGA as a whole has a substantially constant period. It would operate at a speed of [Delta] T).

  As described above, in this embodiment, the waveform reproduction period (ΔT) can be shortened as much as possible, and for example, ΔT = 5 μsec can be easily realized.

In FIG. 13, when the waveform reproduction cycle (ΔT) as described above is repeated N times, a count end notification signal K is generated from the count comparison circuit 96 at that time, and the process proceeds to the line segment waveform element reproduction process of the next stage. (Steps S ₉ → S ₁₁ → S ₂ ).

Incidentally, in the segment waveform element regeneration process, as shown in FIG. 14, one stage of the line segment waveform element a _i line waveform element end of the next stage by an error on the signal processing of a _{i + 1} of the starting end ( Although it may be slightly deviated from the initial value (q _{i + 1} ), even in such a case, since both overlap each other on the time axis, it can be considered that the two stages are substantially connected. In the present invention, since the start of the line segment waveform element is initialized for each stage, there is also an advantage that the error of the waveform reproduction process is reset (corrected) by switching the stage.

When the last (n-th) stage line segment waveform element reproduction process is completed (step S ₃ ), the reference waveform restoration process is completed at that time, and the comparison determination circuit 108 determines whether the waveform control is good or bad ( step S ₁₂₎ is performed. In this embodiment, at this time, the waveform integration value of the entire reference waveform is obtained in the reference waveform integration circuit 98, and the LD drive current is supplied to the current monitor waveform integration circuit 104 and the laser output monitor waveform integration circuit 106. Since the integrated waveform values of the entire monitor waveform and the entire laser output monitor waveform are obtained, the comparison / determination circuit 108 obtains the difference (error) between the integrated waveform value of the entire reference waveform and the integrated waveform value of the entire monitor waveform. Therefore, it is sufficient to perform a calculation only to determine whether or not the error is within a predetermined allowable value or allowable range, and a pass / fail determination result can be obtained in a very short required time (within 0.1 msec).

In this embodiment, in repeat mode, if the duration T _A of the reference waveform is set to the shortest 0.1 msec, it is possible to easily realize a repetition frequency of 5 kHz.

  The pass / fail determination result obtained by the comparison determination circuit 108 is sent to the CPU 64 at all times or only when a failure result is obtained. The CPU 64 reports the pass / fail determination result (particularly the failure determination result) to the user through the touch panel 20, and displays the monitor waveform on the display of the display unit 20a as necessary.

In FIG. 13, steps S ₁₃ , S ₁₄ , and S ₁₅ are processes for repeating reference waveform reproduction a set number of times (m times) in the repeat mode.

  Although the flow in the CW mode is not shown, it is basically the same as the flow in the single mode or repeat mode described above. However, since the duration of the reference waveform is considerably long in the CW mode, if the entire waveform is continuously monitored, data overflows in the monitor waveform buffer memories 100 and 102.

  In this embodiment, the user can freely select an aspect (entire waveform or repetition of a fixed period) regarding the monitoring period of waveform control. In the single-shot mode or the repeat mode, normally, the duration of one waveform is one continuous monitoring period. On the other hand, in the CW mode, it is also possible to repeatedly perform monitoring at a constant cycle within the duration of one waveform, and the length of the cycle can be arbitrarily selected by the user. The contents selected or set by the user regarding the monitoring period are transmitted from the CPU 64 to the FPGA 66 through the “monitor period designation” data in the parameter data (FIG. 10) of the entire reference waveform.

  For example, when the user selects a repetition of a certain period and selects a monitor period of 3 seconds, the control circuit 82 on the FPGA 66 side through the data memory 80 and the reference waveform parameter data buffer memory 84 sets the monitor period setting value ( 3 seconds) is read and each of the pass / fail judgment sections (100 to 108) is repeatedly made to perform the same monitoring operation as described above every monitoring period (3 seconds). As a result, each of the pass / fail judgment sections (100 to 108) operates at an arbitrarily set cycle as described above, and the comparison judgment circuit 108 monitors the monitor waveform (drive current waveform, laser output waveform) every monitor cycle (3 seconds). The result of the pass / fail judgment about is given. In this case, the monitor waveform buffer memories 100 and 102 do not overflow, and the waveform control quality can be determined with the same time resolution as the single-shot mode or repeat mode.

  In the above-described embodiment, the reference waveform integrated value obtained from the reference waveform restored in the FPGA 66 is compared with the monitor waveform integrated value to determine whether the laser waveform control is good or bad. As another embodiment, the CPU 64 side calculates a reference waveform integrated value based on the set reference waveform, and the FPGA 66 side compares the reference waveform integrated value with the monitor waveform integrated value to determine whether the laser waveform control is good or bad. It is also possible.

  In this case, when a desired reference waveform is input to the CPU 64 through the touch panel 20, the CPU 64 calculates the integration value of the reference waveform and displays the reference waveform integration value together with the reference waveform on the display of the display unit 20a. To do. A user (such as an operator) can adjust the waveform shape, duration, and the like of the reference waveform through the input unit 20b while looking at the reference waveform integral value displayed on the display. When the reference waveform desired by the user is determined, the CPU 64 generates the parameter data (FIG. 11) as described above and stores it in the internal memory or the like, and also stores the waveform integral value of the reference waveform. Keep it. When the reference waveform is used for laser welding, the CPU 64 sends the reference waveform integral value to the FPGA 66 together with all parameter data (FIG. 11) prior to the start of laser welding.

In the FPGA 66, the reference waveform integration value from the CPU 64 is directly loaded into the comparison determination circuit 108. The comparison judgment circuit 108 outputs the monitor waveform integration values from the monitor waveform integration circuits 104 and 106 when the laser welding process for one waveform is completed, that is, immediately after the restoration process for one time of the reference waveform is finished. Compared with the reference waveform integral value, the quality is judged based on the comparison error (step S ₁₂ ). Then, the result of pass / fail judgment is reported to the CPU 64 as described above.

Further, in the above embodiment, the waveform generating period ΔT within FPGA66, throughout the reference waveform, i.e. over all the segments waveform element (a ₁ ~a _n), was fixed to a common value. However, in the present invention, the individual segments waveform element a _1, a _2, method of setting the value of the waveform generating period ΔT independently for each · · a _n are also possible. In this case, CPU 64, as the data of the "line interval time" in the parameter data of the stage may be time set data Ta _i (μsec) which represents the duration that is the stage time of the segment waveform element directly.

As shown in FIG. 15, a ΔT determination circuit 112 is provided in the FPGA 66. The ΔT determining circuit 112, the stage parameter data buffer "rate of change" from the memory 86 data ΔS and "line interval time" read data Ta _i, for example by referring to the table (memory), as shown in FIG. 16 The value (code) of the waveform generation period ΔT corresponding to the value of ΔS is selected. For example, when ΔS> 0.04, 5 μsec is selected as the value of the waveform generation period ΔT, and the code “0000” representing the value of ΔT (5 μsec) is transmitted from the ΔT determination circuit 112 to the control circuit 82 and the reference waveform restoration circuit. 88. When 1E-6 ≧ ΔS> 1E-7, 10 μsec is selected as the value of the waveform generation period ΔT, and the code “0001” representing the value of ΔT (10 μsec) is transmitted from the ΔT determination circuit 112 to the control circuit 82 and A reference waveform restoration circuit 88 is provided. Further, the ΔT determination circuit 112 calculates a set cycle count number N (N = Ta _i / ΔT) in the stage from the selected waveform generation period ΔT and the “line segment section time” Ta _i, and this set cycle The count number N is supplied to the count comparison circuit 96.

  As described above, according to the method of determining the waveform generation period ΔT according to the “change rate” for each stage, for example, as shown in FIG. 17, the change rate of the line segment waveform element increases (the change rate increases). The shorter the waveform generation period ΔT and the smaller the change rate of the line segment waveform element (the lower the change speed), the longer the waveform generation period ΔT, and it is possible to achieve both the accuracy and efficiency of waveform restoration.

  It is also possible to set the period of the waveform reproduction calculation in the reference waveform restoration circuit 88 or the period of the reference waveform signal output in the reference waveform output circuit 90 to a period independent of the waveform generation period ΔT. In particular, when the waveform generation period ΔT is long, it is preferable to set the period of the waveform reproduction calculation or the period of the reference waveform signal output to a short value.

  As mentioned above, although preferred embodiment of this invention was described, embodiment mentioned above does not limit this invention. Those skilled in the art can make various modifications and changes in specific embodiments without departing from the technical idea and technical scope of the present invention.

  For example, in the waveform control function, it is possible to omit the modulation option or to fix the resolution to one scale. In this case, the “modulation flag / resolution flag” data is omitted from the stage parameter data. Is also possible.

  Further, various modifications can be made in each part of the fiber laser welding apparatus. For example, the fiber laser oscillator 10 can be replaced with a YAG laser oscillator or the like. The laser processing method and laser processing apparatus of the present invention are not limited to laser welding, and can be applied to other laser processing such as drilling, cutting, and marking.

It is a block diagram which shows the structure of the laser processing apparatus (fiber laser welding apparatus) in one Embodiment of this invention. An example of the reference waveform in single oscillation mode It is a figure which shows an example of the repetitive reference waveform in repeat mode. It is a figure which shows an example of the reference waveform in CW mode. It is a block diagram which shows the structure of the control part in the laser processing apparatus of embodiment. It is a figure for demonstrating the meaning of the initial value, change rate, and line segment area time which are contained in the parameter of the stage in embodiment. It is a figure for demonstrating the significance of the modulation flag contained in the parameter of the stage in embodiment. It is a figure for demonstrating the significance of the resolution flag contained in the parameter of the stage in embodiment. It is a figure which shows the example of a format of the parameter data of 1 stage in embodiment. It is a figure which shows the example of a format of the basic parameter data of the whole basic waveform in embodiment. It is a figure which shows the example of a data format for collectively managing all the parameter data which concern on one basic waveform in embodiment. It is a block diagram which shows the circuit structure in FPGA in embodiment. It is a flowchart figure which shows the whole process sequence of the circuit in FPGA in the single mode or repeat mode of embodiment. It is a figure which shows the example when the termination | terminus of a line segment waveform element shifts in embodiment. It is a block diagram which shows the circuit structure in FPGA in another embodiment. It is a figure which shows an example of the table used when changing a calculation output period according to the change rate of each line segment waveform element in embodiment. It is a figure which shows the effect | action of waveform reproduction | regeneration in the case of changing a calculation output period according to the change rate of each line segment waveform element.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Fiber laser oscillator 12 Laser power supply 16 Laser emission part 18 Control part 20 Touch panel 64 CPU (microcomputer)
66 FPGA (Field Programmable Gate Array)
80 data memory 82 control circuit 84 basic parameter data buffer memory 86 stage parameter data buffer memory 88 reference waveform restoration operation circuit 90 reference waveform output circuit 95 cycle counter 96 count comparison circuit 98 reference waveform integration circuit 100 current monitor waveform buffer Memory 102 Laser output monitor waveform buffer memory 104 Current monitor waveform integration circuit 106 Laser output monitor waveform integration circuit 108 Comparison determination circuit 112 ΔT determination circuit

Claims (25)

A first step of connecting a plurality of line segment waveform elements along the time axis to set a desired reference waveform;
For each of the line segment waveform elements, at least initial value data representing the start value, change rate data representing the slope, and line segment interval time data representing the length of time from the start to the end. A second step of generating as one stage parameter data;
A predetermined calculation process is performed based on parameter data for each stage along the time axis to reproduce the line segment waveform element, and the line segment waveform element is substantially connected over the entire stage to generate the reference waveform. A third step to restore;
And a fourth step of varying the output of pulsed or continuous wave laser light used for desired laser processing according to the restored reference waveform. In the second step, when the fixed period is ΔT and the line segment section time is N × ΔT (N is a positive integer) for each of the line segment waveform elements, the data representing the line segment section time To generate data representing the numerical value N as
In the third step, a change amount for the fixed period ΔT is obtained from the change rate, and the change amount for the fixed period is sequentially added N times starting from the initial value.
The laser processing method according to claim 1. A fifth step of setting at least a desired wave height reference value as one of the parameters of the reference waveform;
In the second step and the third step, the change rate is used as a ratio to the wave height reference value.
The laser processing method according to claim 1 or 2. In the second step, flag data representing the resolution of the change rate is further generated as one of stage parameter data,
In the third step, the rate of change is used with the resolution indicated by the resolution flag.
The laser processing method as described in any one of Claims 1-3. In the second step, a modulation flag data indicating whether or not to superimpose a preset modulation waveform on the line segment waveform element is further generated as one of stage parameter data;
In the third step, the modulation waveform is superimposed on the reproduced line segment waveform element conditionally according to an instruction of the modulation flag.
The laser processing method as described in any one of Claims 1-4. In the fourth step,
Measuring a driving current for light emission supplied to an excitation light source for optically exciting an active medium in an optical resonator that oscillates and outputs the laser light;
Varying the drive current so that the measured value of the drive current follows the restored reference waveform;
The laser processing method as described in any one of Claims 1-5. A sixth step of performing an integration operation on the reference waveform being restored during the period in which the laser beam is oscillated and output;
A seventh step of performing an integration operation on the waveform of the drive current based on the measured value of the drive current during the period of oscillation output of the laser beam;
Immediately after the oscillation output of the laser beam is ended or interrupted, the integrated value of the reference waveform and the integrated value of the drive current waveform are compared, and determination of pass / fail regarding the output of the laser beam based on the comparison error The laser processing method according to claim 6, further comprising: an eighth step of performing In the fourth step,
Measure the output of the excitation light generated from the excitation light source for optically exciting the active medium in the optical resonator that oscillates and outputs the laser light,
Varying the drive current for light emission supplied to the excitation light source so that the output of the excitation light follows the reference waveform;
The laser processing method as described in any one of Claims 1-5. A sixth step of performing an integration operation on the reference waveform being restored during the period in which the laser beam is oscillated and output;
A seventh step of performing an integration operation on the excitation output based on a measured value of the excitation output during a period of oscillation output of the laser beam;
Immediately after ending or stopping the oscillation output of the laser beam, the integrated value of the reference waveform and the integrated value of the excitation output waveform are compared, and determination of pass / fail regarding the output of the laser beam based on the comparison error The laser processing method according to claim 8, further comprising: an eighth step of performing In the fourth step,
Measuring the laser output of the laser beam;
The emission drive current supplied to the excitation light source for optically exciting the active medium in the optical resonator that oscillates and outputs the laser light is varied so that the measured value of the laser output follows the reference waveform. To
The laser processing method as described in any one of Claims 1-5. A sixth step of performing an integration operation on the reference waveform being restored during the period in which the laser beam is oscillated and output;
A seventh step of performing an integration operation on the laser output based on a measured value of the laser output during a period of oscillation output of the laser beam;
Immediately after ending or stopping the oscillation output of the laser beam, the integrated value of the reference waveform and the integrated value of the laser output waveform are compared, and determination of pass / fail regarding the output of the laser beam based on the comparison error The laser processing method according to claim 10, further comprising: an eighth step of performing A ninth step of storing parameter data for all stages in the memory with respect to the reference waveform, or transmitting the data via communication means;
The tenth step of reading parameter data of each stage with respect to the reference waveform in the order of stages along a time axis from the memory or receiving via the communication means. The laser processing method as described in. A reference waveform setting unit for connecting a plurality of line segment waveform elements along the time axis to set a desired reference waveform;
For each of the line segment waveform elements, at least initial value data representing the start value, change rate data representing the slope, and line segment interval time data representing the length of time from the start to the end. A stage / parameter data generation unit for generating parameter data for one stage;
A predetermined calculation process is performed based on parameter data for each stage along the time axis to reproduce the line segment waveform element, and the line segment waveform element is substantially connected over the entire stage to generate the reference waveform. A reference waveform restoring unit to restore,
A laser processing apparatus comprising: a laser output variable unit configured to vary an output of pulsed or continuous wave laser light used for desired laser processing according to the restored reference waveform.   When the stage parameter data generation unit sets ΔT as a fixed period and the line segment section time is N × ΔT (N is a positive integer) for each of the line segment waveform elements, the line segment section time is The laser processing apparatus according to claim 13, wherein data representing a numerical value N is generated as data to be represented.   The reference waveform restoration unit obtains a unit change amount per fixed period ΔT from the change rate, and the unit change amount of the line segment waveform element that is being reproduced is reproduced for each constant period ΔT starting from the initial value. The laser processing apparatus according to claim 14, wherein the laser processing apparatus is added to a terminal end. The stage parameter data generation unit further generates modulation flag data as one of the stage parameter data that indicates whether or not to superimpose a predetermined predetermined modulation waveform on the line segment waveform element. ,
The reference waveform restoration unit obtains a unit change amount per fixed period ΔT from the change rate, and conditionally changes the unit change every fixed period ΔT starting from the initial value as a starting point according to an instruction of the modulation flag. Adding an amount and the modulated waveform to the end of the segment waveform element being reproduced;
The laser processing apparatus according to claim 14.   The laser processing apparatus according to claim 16, wherein the reference waveform restoration unit includes a modulation waveform storage unit that holds data for one cycle of the modulation waveform. The reference waveform setting unit and the stage parameter data generation unit are constituted by a CPU (microcomputer),
The reference waveform restoration unit is constructed in an FPGA (Field Programmable Gate Array),
The laser processing apparatus as described in any one of Claims 13-17.   19. The laser processing apparatus according to claim 18, wherein a stage parameter data memory that receives and holds all parameter data including parameter data of each stage related to the reference waveform from the CPU is further built in the FPGA. The laser output variable unit is
An optical resonator including an active medium for oscillating and outputting the laser beam;
An excitation light source for optically exciting the active medium;
A laser power source for supplying a driving current for light emission to the light emitting unit;
A current measurement unit for measuring the drive current;
The laser processing apparatus according to any one of claims 13 to 19, further comprising: a control unit that controls the drive circuit so that a measured value of the drive current follows the reference waveform. A reference waveform integration circuit that performs an integration operation on the reference waveform being restored during the period in which the laser beam is oscillated and output;
A monitor waveform integration circuit that performs an integration operation on the waveform of the drive current based on the measured value of the drive current during a period in which the laser beam is oscillated and output;
Immediately after the oscillation output of the laser beam is finished or interrupted, the integrated value of the reference waveform is compared with the integrated value of the drive current waveform, and the quality determination regarding the output of the laser beam is made based on the comparison error. The laser processing apparatus according to claim 20, wherein the pass / fail judgment circuit for performing is constructed in the FPGA. The laser output variable unit is
An optical resonator including an active medium for oscillating and outputting the laser beam;
An excitation light source for optically exciting the active medium;
A laser power supply for supplying a driving current for light emission to the excitation light source;
An excitation output measuring unit for measuring the output of the excitation light generated from the excitation light source;
The laser processing apparatus according to claim 13, further comprising: a control unit that controls the drive circuit so that a measured value of the excitation output follows the reference waveform. A reference waveform integration circuit that performs an integration operation on the reference waveform being restored during the period in which the laser beam is oscillated and output;
A monitor waveform integration circuit that performs an integration operation on the waveform of the excitation output based on the measured value of the excitation output during a period in which the laser beam is oscillated and output;
Immediately after the oscillation output of the laser beam is completed or interrupted, the integrated value of the reference waveform and the integrated value of the excitation output waveform are compared, and determination of pass / fail regarding the output of the laser beam based on the comparison error The laser processing apparatus according to claim 22, wherein the pass / fail judgment circuit for performing is constructed in the FPGA. The laser output variable unit is
An optical resonator including an active medium for oscillating and outputting the laser beam;
An excitation light source for optically exciting the active medium;
A laser power supply for supplying a driving current for light emission to the excitation light source;
A laser output measuring unit for measuring the output of the laser beam oscillated and output from the optical resonator;
The laser processing apparatus according to claim 13, further comprising: a control unit that controls the drive circuit so that a measured value of the laser output follows the reference waveform. A reference waveform integration circuit that performs an integration operation on the reference waveform being restored during the period in which the laser beam is oscillated and output;
A monitor waveform integration circuit that performs an integration operation on the waveform of the laser output based on the measured value of the laser output during a period in which the laser beam is oscillated and output;
Immediately after the oscillation output of the laser beam is finished or interrupted, the integrated value of the reference waveform is compared with the integrated value of the laser output waveform, and the quality determination regarding the output of the laser beam is made based on the comparison error 25. The laser processing apparatus according to claim 24, wherein the pass / fail judgment circuit for performing is constructed in the FPGA.

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