JP2008068305A - Laser machining method and laser machining device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a laser machining method and a laser machining device where a workpiece can be quickly subjected to laser machining with high efficiency. <P>SOLUTION: In the laser machining method where a workpiece is irradiated with a laser beam while outputting a machining gas thereto, beam on timings are decided in such a manner that the laser beam is turned on at the timing before the timing in which gas pressure reaches the set gas pressure in previously set machining conditions, and the laser irradiation is performed to the workpiece at the timing after the timing in which the gas pressure reaches the set gas pressure. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a laser processing method and a laser processing apparatus for performing laser processing on a workpiece while irradiating the workpiece with a processing gas and a laser beam.

  As an apparatus for processing various workpieces (workpieces) such as iron, aluminum, and resin, there is a laser processing apparatus that performs processing by irradiating the workpiece with laser light. In such a laser processing apparatus, a processing gas (assist gas) for accelerating melting or blowing off a material with a high pressure is used for a workpiece that has reached a melting point by laser irradiation.

  Processing conditions (laser beam output and frequency, laser beam focal position, processing gas pressure, gas type, processing speed) when laser processing a workpiece are determined by the workpiece (processing material and plate thickness), etc. If laser processing is performed under processing conditions different from preset processing conditions (setting values), processing failure occurs.

  For example, the gas pressure (processing gas pressure) at the time of laser processing is measured by using a pressure sensor disposed in a processing gas pipe. Then, the actual pressure (measured gas pressure) with respect to a predetermined command pressure is fed back to control the processing gas pressure to be a predetermined gas pressure. When laser processing is performed in a state where the processing gas does not reach a predetermined pressure when performing laser processing, the melted workpiece adheres to the processing lens (lens that condenses the laser light), which causes processing defects. As a result, the expensive processing lens is damaged, and a lot of time is spent on the restoration work. For this reason, control of the processing gas pressure and control of the irradiation timing of the laser beam are regarded as important in laser processing of the workpiece.

  Further, it is desired that a laser processing apparatus processes a workpiece efficiently and quickly. For this reason, when laser processing is performed by a laser processing apparatus, it is necessary to quickly reach a predetermined processing gas pressure, irradiate laser light, and start laser processing. In the conventional laser processing apparatus, the laser beam irradiation timing is set to a predetermined fixed time (fixed timing). For example, the laser beam irradiation timing (rise timing) is set to the same timing under all the processing conditions so that laser irradiation is performed after the processing gas pressure reaches a predetermined gas pressure. For this reason, depending on the processing conditions, it may take a long time until the laser irradiation is performed after the processing gas pressure reaches a predetermined gas pressure, which increases the time required for laser processing and unnecessary processing. Was consuming gas.

  Moreover, in the laser processing apparatus described in Patent Document 1, a pressure sensor for detecting the assist gas pressure in the processing head is provided in the processing head, and the assist gas pressure is controlled based on the detection value of the pressure sensor.

JP-A-5-185276

  However, in the above conventional technique, when laser processing on the workpiece is started, the laser beam is turned on after the processing gas pressure reaches a predetermined pressure, and therefore, after reaching the processing gas pressure set as the processing conditions The time until the laser beam is irradiated (the time from the beam ON to the laser irradiation) is wasted. For this reason, there was a problem that the workpiece could not be laser processed efficiently and quickly.

  The present invention has been made in view of the above, and an object of the present invention is to obtain a laser processing method and a laser processing apparatus for laser processing a workpiece efficiently and quickly.

  In order to solve the above-described problems and achieve the object, the present invention provides a preset laser processing method for performing laser processing on a workpiece by irradiating a laser beam while outputting a processing gas to the workpiece. The laser beam is turned on at a timing earlier than the timing at which the set gas pressure is reached under the processing conditions, and the workpiece is irradiated with laser at a timing after the timing at which the set gas pressure is reached. It is characterized in that a beam-on timing for turning on the laser beam is determined so as to be performed.

  According to this invention, the laser beam is turned on at a timing before the timing at which the set gas pressure is reached, and the workpiece is irradiated with laser at a timing after the timing at which the set gas pressure is reached. Since the beam-on timing is determined, there is an effect that the workpiece can be laser processed efficiently and quickly.

  Embodiments of a laser processing method and a laser processing apparatus according to the present invention will be described below in detail with reference to the drawings. Note that the present invention is not limited to the embodiments.

Embodiment FIG. 1 is a block diagram showing a configuration of a laser processing apparatus according to an embodiment of the present invention. The laser processing apparatus 1 is an apparatus for laser processing a workpiece (workpiece) using a processing gas (assist gas), and includes a control unit 10, a gas output unit 20, a laser oscillator 30, and a processing head (laser irradiation unit) 40. It has.

  The control unit 10 performs NC control when the workpiece is laser processed. The control unit 10 includes a data table storage unit 11, a beam ON timing determination unit 12, and the like, and controls the gas output unit 20, the laser oscillator 30, and the processing head 40.

  The data table storage unit 11 stores a data table (a data table 100 to be described later) used when determining the timing (beam ON timing) for turning on the laser beam (laser beam).

  The beam ON timing determination unit 12 determines the beam ON timing when starting laser processing based on the data table 100 stored in the data table storage unit 11 and the like. The control unit 10 causes the laser oscillator 30 to oscillate laser light at a predetermined timing based on the beam ON timing determined by the beam ON timing determination unit 12.

  The gas output unit 20 outputs (supplies) a processing gas to the processing head 40 based on an instruction from the control unit 10. The gas output unit 20 includes a gas cylinder 21 serving as a processing gas supply source, and a gas pressure measurement unit (gas pressure measurement unit) 22. The gas pressure measurement unit 22 includes a pressure sensor, for example, and measures the gas pressure (gas pressure value) of the processing gas output from the gas cylinder 21 to the processing head 40. The gas pressure measuring unit 22 inputs the measured processing gas pressure (measured value) to the control unit 10.

  The laser oscillator 30 oscillates (supplies) laser light to the machining head 40 based on an instruction from the control unit 10. The processing head 40 performs laser processing on the workpiece by irradiating the workpiece with the processing gas supplied from the gas output unit 20 and the laser beam supplied from the laser oscillator 30. The machining head 40 moves the position relative to the workpiece based on an instruction from the control unit 10.

  Here, a detailed configuration of the control unit 10 which is a main feature of the present invention will be described. FIG. 2 is a block diagram illustrating a detailed configuration of the control unit. The control unit 10 includes a data table storage unit 11, a beam ON timing determination unit (gas pressure determination unit, beam on timing determination unit) 12, a processing condition storage unit 14, a pressure difference calculation unit 13, a pressure command unit 15, and a beam ON command. A portion 16 is provided. The processing condition storage unit 14 stores processing conditions (for example, a processing gas pressure required when starting laser processing) when processing a workpiece.

  The pressure difference calculation unit 13 is connected to the gas pressure measurement unit 22, the processing condition storage unit 14, the pressure command unit 15, and the beam ON timing determination unit 12 of the gas output unit 20. The pressure difference calculation unit 13 includes a processing gas pressure within the processing conditions stored in the processing condition storage unit 14 (a preset processing gas pressure) and a processing gas pressure measured by the gas pressure measurement unit 22 (actually output). And the difference in gas pressure between them is calculated. The pressure difference calculation unit 13 transmits the calculated gas pressure difference (pressure difference) to the pressure command unit 15.

  The pressure command unit 15 causes the gas output unit 20 to adjust the pressure of the gas output from the gas output unit 20 to the machining head 40 using the pressure difference sent from the pressure difference calculation unit 13. The pressure command unit 15 transmits instruction information (command) for designating the gas pressure to the gas output unit 20 when the gas output unit 20 adjusts the pressure of the gas output from the gas output unit 20.

  The beam ON timing determination unit 12 is connected to the pressure difference calculation unit 13, the processing condition storage unit 14, the beam ON command unit 16, and the data table storage unit 11. The beam ON timing determination unit 12 is configured to turn the laser beam ON based on the processing conditions stored in the processing condition storage unit 14, the data table 100 stored in the data table storage unit 11, and the pressure difference calculated by the pressure difference calculation unit 13. Determine the timing (timing of irradiating the workpiece with laser light). The beam ON timing determination unit 12 transmits the determined beam ON timing to the beam ON command unit 16.

  The beam ON command unit 16 causes the laser oscillator 30 to oscillate the laser beam at a predetermined timing (beam ON) based on the beam ON timing received from the beam ON timing determination unit 12.

  Next, an operation procedure of the laser processing apparatus 1 will be described. FIG. 3 is a flowchart showing an operation procedure of the laser processing apparatus according to the embodiment of the present invention. In the control unit 10 of the laser processing apparatus 1, the pressure difference calculation unit 13 and the beam ON timing determination unit 12 read the processing conditions of the workpiece from the processing condition storage unit 14 (step S10).

  The pressure difference calculation unit 13 extracts the processing gas pressure (set value) when processing the workpiece from the processing conditions stored in the processing condition storage unit 14 and transmits the processing gas pressure to the pressure command unit 15. The pressure command unit 15 instructs the gas output unit 20 on the pressure of the gas output from the gas output unit 20 based on the processing gas pressure sent from the pressure difference calculation unit 13 (transmission of a gas pressure command) (step S20). .

  The gas output unit 20 outputs the processing gas to the processing head 40 at a predetermined pressure based on the gas pressure command from the pressure command unit 15. The processing gas from the gas output unit 20 to the processing head 40 is blown onto the workpiece. At this time, the gas pressure measurement unit 22 measures the pressure of the processing gas output from the gas output unit 20 to the processing head 40 and transmits the measured value of the processing gas pressure to the pressure difference calculation unit 13. The gas pressure measuring unit 22 measures the processing gas pressure being output while the gas output unit 20 outputs the processing gas to the processing head 40, and the measured processing gas pressure (measured value) is used as the pressure difference calculating unit 13. Continue to send to.

  The pressure difference calculation unit 13 compares the processing gas pressure within the processing conditions stored in the processing condition storage unit 14 with the processing gas pressure measured by the gas pressure measurement unit 22, and calculates the difference in gas pressure between them. (Step S30). The pressure difference calculation unit 13 transmits the calculated pressure difference to the pressure command unit 15 and the beam ON timing determination unit 12.

  The pressure difference calculation unit 13 continues to calculate the pressure difference while receiving the measurement value of the processing gas pressure from the gas pressure measurement unit 22. The pressure difference calculation unit 13 continues to transmit the pressure difference calculation result to the beam ON timing determination unit 12 until the beam ON timing determination unit 12 determines the beam ON timing. Further, the pressure difference calculation unit 13 continues to transmit the calculation result of the pressure difference to the pressure command unit 15 while receiving the measurement value of the processing gas pressure from the gas pressure measurement unit 22.

  The pressure command unit 15 causes the gas output unit 20 to adjust the pressure of the gas output from the gas output unit 20 using the pressure difference sent from the pressure difference calculation unit 13. The pressure command unit 15 adjusts the pressure of the gas output by the gas output unit 20 so as to approach the processing gas pressure set within the processing conditions.

  The beam ON timing determination unit 12 is output from the gas output unit 20 using the pressure difference sent from the pressure difference calculation unit 13 after a predetermined time (for example, 2 msec) has elapsed since the start of processing gas output. A rate of increase in gas pressure (a rate of increase in gas pressure) is calculated (step S40). The timing at which the beam ON timing determination unit 12 calculates the gas pressure increase rate may be fixedly set in advance, or may be set for each processing condition in the data table 100. Next, the beam ON timing determination unit 12 determines whether the gas pressure increase rate (the increase rate of the processing gas pressure value) is an inclination within a predetermined range corresponding to the processing conditions (step S50).

  Here, the beam ON timing determination unit 12 determines the gas pressure based on the processing conditions stored in the processing condition storage unit 14, the data table 100 stored in the data table storage unit 11, and the pressure difference calculated by the pressure difference calculation unit 13. It is determined whether or not the rate of increase is within a predetermined range. Specifically, an allowable range of the slope of the gas pressure increase rate corresponding to the machining conditions is extracted from the data table 100, and the calculated gas pressure increase rate is included in the allowable range of the extracted gas pressure increase rate. It is judged whether it is (step S50).

  Here, the configuration of the data table 100 stored in the data table storage unit 11 will be described. FIG. 4 is a diagram illustrating an example of the configuration of the data table. The data table 100 is a data table in which the “machining conditions” of the workpiece, the “measurement timing” of the machining gas pressure, the allowable range of the “tilt” of the gas pressure increase rate, and the “beam ON timing” are associated with each other.

  The “machining condition” of the workpiece corresponds to the machining condition stored in the machining condition storage unit 14. The “measurement timing” of the processing gas pressure indicates the time from when the gas output unit 20 starts outputting the processing gas to when the beam ON timing determination unit 12 starts determining the beam ON timing. For example, when the “measurement timing” is 1 ms later, the beam ON timing determination unit 12 is based on the processing gas pressure measured by the gas pressure measurement unit 22 1 ms after the gas output unit 20 starts outputting the processing gas. Determines (determines) the beam ON timing.

  The allowable range of the “inclination” of the gas pressure increase rate allows the beam to be turned on after a predetermined time elapses with respect to the inclination of the gas pressure increase rate calculated by the beam ON timing determination unit 12. It is a range. That is, the “slope” here is a gas pressure increase rate that guarantees that the processing gas pressure set in the processing conditions will be reached after a predetermined time has elapsed. When the slope of the gas pressure increase rate calculated by the beam ON timing determination unit 12 is within the range of “slope” set in the data table 100, the beam is turned on after a predetermined time corresponding to this “slope” has elapsed. Judge that you want to.

  “Beam ON timing” is the time from when the beam ON timing determination unit 12 determines that the beam is turned on after a predetermined time has elapsed until the laser beam is turned on by the laser oscillator 30.

  When calculating the slope of the gas pressure increase rate, the beam ON timing determination unit 12 calculates the slope of the gas pressure increase rate using the origin and one point other than the origin (gas pressure at a predetermined time). Alternatively, the slope of the gas pressure increase rate may be calculated using two points other than the origin.

  When the beam ON timing determination unit 12 determines that the calculated gas pressure increase rate is within the allowable range of the gradient of the gas pressure increase rate extracted from the data table 100 (Yes in step S50), the data table 100 is stored. Use to determine the beam ON timing of the laser light.

  For example, in the case of the processing condition A, the beam ON timing determination unit 12 determines the beam ON timing based on the processing gas pressure measured by the gas pressure measurement unit 22 1 msec after the gas output unit 20 starts outputting the processing gas. To decide. At this time, the beam ON timing determination unit 12 determines that the laser beam is turned on after 29 milliseconds if the “gradient” of the calculated gas pressure increase rate is within 10 to 12 (pressure / hour), and the calculated gas If the “inclination” of the pressure increase rate is within 12 to 15 (pressure / hour), it is determined that the laser beam is turned on after 28 milliseconds. The beam ON timing determination unit 12 transmits the determined beam ON timing to the beam ON command unit 16.

  Here, the case where the beam ON timing (after 28 msec or 29 msec) is determined according to the “inclination” of the gas pressure increase rate has been described, but the “inclination” of the gas pressure increase rate as in the processing condition B has been described. May be determined to be in an abnormal state (abnormal gas output) if the allowable range is set to one region (10 to 13 (pressure / time)).

  In the present embodiment, after the processing gas pressure reaches a predetermined set value and stabilizes, the laser beam is turned on before the processing gas pressure is stabilized so that the laser beam can be irradiated onto the workpiece immediately. Get started. FIG. 5 is a diagram for explaining the timing of laser irradiation.

  As shown in the figure, when the calculated slope of the gas pressure rise rate is within the allowable range of the slope of the gas pressure rise rate extracted from the data table 100, immediately after the processing gas pressure is stabilized, the workpiece is immediately transferred to the workpiece. The laser beam is turned on before the processing gas pressure is stabilized so that the laser beam can be irradiated. For this reason, in the embodiment, the laser is irradiated for each processing condition in advance so that the laser irradiation is performed in a state where the processing gas pressure is stable when the laser light beam ON is started and the time required for the laser light stabilization has elapsed. The timing for starting the light beam ON is set in advance.

  The beam ON command unit 16 transmits a beam ON command to the laser oscillator 30 based on the beam ON timing received from the beam ON timing determination unit 12 (step S60), and oscillates the laser light to the laser oscillator 30 (beam ON). Let

  The laser oscillator 30 starts laser oscillation to the machining head 40 after receiving the beam ON command. Thereafter, after a predetermined time (for example, 20 msec) elapses, the laser oscillator 30 starts up, and laser light is output from the laser oscillator 30 to the processing head 40. Thereby, laser processing of the workpiece is performed by the processing gas and laser light output from the processing head 40 (step S70).

  Thereafter, the pressure difference calculation unit 13 compares the gas pressure within the processing conditions stored in the processing condition storage unit 14 with the gas pressure measured by the gas pressure measurement unit 22, and calculates the difference in gas pressure between them. The pressure difference is monitored (step S80). The pressure difference calculation unit 13 transmits the calculated pressure difference to the pressure command unit 15, and the pressure command unit 15 causes the gas output unit 20 to adjust the gas pressure as necessary.

  On the other hand, when the beam ON timing determination unit 12 determines that the gas pressure increase rate calculated within the allowable range of the gradient of the gas pressure increase rate extracted from the data table 100 is not included (No in step S50), the beam ON timing is determined. The determination unit 12 determines whether or not the pressure difference calculated by the pressure difference calculation unit 13 is within a predetermined range (whether or not the processing gas pressure output from the gas output unit 20 has reached the pressure specified by the processing conditions). ) Is checked (step S90).

  When the processing gas pressure output from the gas output unit 20 reaches the pressure specified by the processing conditions (step S100, Yes), the beam ON timing determination unit 12 transmits an instruction to turn on the beam to the beam ON command unit 16.

  When receiving the beam ON instruction from the beam ON timing determination unit 12, the beam ON command unit 16 transmits a beam ON command to the laser oscillator 30 (step S60), and causes the laser oscillator 30 to oscillate the laser beam (beam ON). .

  Thereafter, the laser oscillator 30 starts laser oscillation to the machining head 40, and the workpiece is laser machined by the machining gas and laser light output from the machining head 40 (step S70). Then, the pressure difference calculation unit 13 compares the gas pressure in the processing conditions stored in the processing condition storage unit 14 with the gas pressure measured by the gas pressure measurement unit 22, and calculates the difference in gas pressure between them. The pressure difference is monitored (step S80). The pressure difference calculation unit 13 transmits the calculated pressure difference to the pressure command unit 15, and the pressure command unit 15 causes the gas output unit 20 to adjust the gas pressure as necessary.

  On the other hand, if the processing gas pressure output from the gas output unit 20 within a predetermined time does not reach the pressure specified by the processing conditions (No in step S100), an alarm for notifying the abnormality of the processing gas pressure is output. Then, the laser processing apparatus 1 is stopped (step S110).

  As described above, in the present embodiment, it is determined whether or not the beam ON can be started after a predetermined time has elapsed based on the slope of the gas pressure increase rate. If it is determined that the beam ON can be started after the lapse of a predetermined time, the beam ON of the laser beam is started before the processing gas pressure is stabilized, so that the processing gas pressure becomes a predetermined set value. Immediately after reaching and stabilizing, the workpiece can be irradiated with laser light.

  Here, the difference between the laser processing method (beam ON timing control method) conventionally used and the laser processing method according to the embodiment will be described. FIG. 6 is a diagram for explaining the difference between the conventional laser processing method and the laser processing method according to the embodiment.

  In FIG. 6, the beam ON timing in the conventional laser processing method is shown on the upper side in the drawing, and the beam ON timing in the laser processing method according to the embodiment is shown on the lower side in the drawing.

  In the conventional laser processing method, after a predetermined processing gas pressure set in processing conditions is reached and the processing gas pressure is stabilized, a laser beam ON command is issued. Then, after the time required for stabilization of the laser light has elapsed, the workpiece is irradiated with laser. For this reason, the time from when the beam ON command is issued until the laser irradiation is performed is a wasteful time in laser processing, and a long time is required for laser processing.

  On the other hand, in the laser processing method according to the embodiment, the laser beam ON is started before reaching the predetermined processing gas pressure set in the processing conditions and stabilizing the processing gas pressure. After reaching the predetermined set value and stabilizing, the workpiece can be irradiated with laser light immediately. For this reason, laser processing can be performed in a short time without wasting time from when the beam ON command is issued until laser irradiation is performed.

  In the present embodiment, since the gas pressure measuring unit 22 measures the gas pressure of the processing gas output from the gas cylinder 21 to the processing head 40, an accurate processing gas pressure can be measured. FIG. 7 is a diagram for explaining the position of the gas pressure measurement unit disposed in the laser processing apparatus.

  The laser processing apparatus 1 includes a gas cylinder 21, a control valve 54, an opening / closing valve 55, and a gas pressure measuring unit 22 in the gas output unit 20. The processing gas from the gas cylinder 21 is sent to the processing head 40 via the opening / closing valve 55 and the control valve 54. The gas pressure measuring unit 22 is disposed between the control valve 54 and the processing head 40 so that the pressure of the processing gas sent to the processing head 40 via the control valve 54 can be measured.

  For example, when the gas pressure measuring unit 22 (pressure sensor) is disposed in the machining head 40, when the pierced hole is penetrated into the workpiece by laser machining, it becomes easy to be subjected to a sudden pressure fluctuation at the corner R or the like and stable. It becomes difficult to perform the processed. Further, the pressure sensor is likely to be damaged by the reflected light of the sputtering or laser light. In addition, there is a greater possibility that the pressure sensor will be affected by the surrounding environment near the machining point. Furthermore, since the pressure sensor is attached to the inside of the processing head 40 (inside the chamber), the pressure sensor has irregularities on the inner wall portion of the chamber, which may disturb the flow of the processing gas.

  On the other hand, in the present embodiment, since the pressure sensor is disposed between the control valve 54 and the machining head 40, it is difficult to be affected by sudden pressure fluctuations. Further, the pressure sensor can be prevented from being damaged by sputtering or reflected light of the laser beam. Further, the management of the processing gas pressure during processing does not need to be performed using the gas pressure at the processing head 40, and may be managed by the pressure between the control valve 54 and the processing head 40. Further, since the pressure sensor is not attached to the inside of the processing head 40, the inner wall portion of the chamber becomes a uniform surface, and the processing gas can be rectified. Thereby, in embodiment, compared with the measurement of the conventional gas pressure, a gas pressure can be measured correctly. Therefore, it is possible to accurately determine an appropriate beam ON timing.

  In the embodiment, the beam ON timing is determined using the data table 100, but the beam ON timing of the laser beam may be calculated for each workpiece processing based on the processing conditions, the pressure difference, and the like. Good. In this case, if the beam ON timing (the time from when it is determined that the beam is turned on after a predetermined time elapses until the laser beam is turned on) becomes a negative value, the beam is immediately turned on to the laser oscillator 30. Let

  In the embodiment, the beam ON is performed after elapse of a predetermined time based on the inclination of the gas pressure increase rate calculated by the beam ON timing determination unit 12 and the “inclination” of the gas pressure increase rate set in the data table 100. It is determined whether or not the beam is turned on, but it may be determined whether or not the beam is turned on after the elapse of a predetermined time other than the inclination of the gas pressure increase rate. When determining whether or not to turn on the beam after a lapse of a predetermined time other than the inclination of the gas pressure increase rate, for example, based on the relationship between the processing gas pressure and the elapsed time since the start of processing gas output, the processing gas pressure Predicts the time (pressure arrival timing) until it reaches a predetermined set value and stabilizes. Then, the timing for turning on the beam is determined based on the predicted time.

  As described above, according to the embodiment, since the laser beam ON timing is determined so that laser irradiation to the workpiece is not started before the processing gas pressure is stabilized, the processing defect of the workpiece can be reduced. It becomes possible to prevent spatter adhesion to the processed lens. In addition, when it is determined that the beam ON may be started after the lapse of a predetermined time, when the processing gas pressure reaches a predetermined set value and stabilizes, the irradiation of the laser beam to the workpiece can be started immediately. Since the laser beam is turned on before the processing gas pressure is stabilized, the processing from the processing gas output to the laser processing can be performed in a short time. In addition, since the time from the output of the processing gas to the start of laser processing is shortened, it is possible to perform laser processing with a small amount of gas consumption. Therefore, the workpiece can be laser processed efficiently and quickly.

  Further, since the beam ON timing is determined according to the “inclination” of the gas pressure increase rate, it becomes possible to turn on the laser beam at an appropriate timing according to the “inclination” of the gas pressure increase rate.

  Further, since it is determined whether or not the pressure of the processing gas reaches a predetermined set value after a predetermined time elapses based on the slope of the gas pressure increase rate of the measured processing gas pressure, the predetermined time It is possible to accurately determine whether the pressure of the processing gas reaches a predetermined set value after the elapse of time and stabilizes. This makes it possible to accurately determine an appropriate timing for turning on the laser beam.

  Also, for example, based on the relationship between the elapsed time from the start of the processing gas output and the processing gas pressure, the time until the processing gas pressure reaches a predetermined set value and stabilizes is predicted. Based on this, it is determined whether or not the pressure of the processing gas reaches a predetermined set value after a predetermined time has elapsed and is stabilized. Therefore, it is possible to accurately determine whether or not the pressure of the processing gas reaches a predetermined set value and stabilizes after the lapse of a predetermined time. This makes it possible to accurately determine an appropriate timing for turning on the laser beam.

  Further, since the gas pressure measuring unit 22 (pressure sensor) is disposed between the control valve 54 and the processing head 40, it is possible to appropriately manage the processing gas pressure during laser processing, and output the processing gas. It is possible to determine an accurate beam ON timing so that the time from the start to the laser processing is short.

  As described above, the laser processing method and the laser processing apparatus according to the present invention are suitable for setting the beam-on timing of the laser beam when performing laser processing.

It is a block diagram which shows the structure of the laser processing apparatus which concerns on embodiment. It is a block diagram which shows the detailed structure of a control part. It is a flowchart which shows the operation | movement procedure of the laser processing apparatus which concerns on embodiment. It is a figure which shows an example of a structure of a data table. It is a figure for demonstrating the timing of laser irradiation. It is a figure for demonstrating the difference between the conventional laser processing method and the laser processing method which concerns on embodiment. It is a figure for demonstrating the position of the gas pressure measurement part arrange | positioned at a laser processing apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Laser processing apparatus 10 Control part 11 Data table memory | storage part 12 Beam ON timing determination part 13 Pressure difference calculation part 14 Processing condition memory | storage part 15 Pressure command part 16 Beam ON command part 20 Gas output part 21 Gas cylinder 22 Gas pressure measurement part 30 Laser Oscillator 40 Processing head 54 Control valve 55 Open / close valve 100 Data table

Claims (6)

In a laser processing method for performing laser processing of the workpiece by irradiating a laser beam while outputting a processing gas to the workpiece,
The laser beam is turned on at a timing earlier than the timing at which the preset gas pressure for the processing conditions set in advance is reached, and laser is applied to the workpiece at a timing later than the timing at which the preset gas pressure is reached. A laser processing method for determining a beam-on timing for turning on the laser beam so that irradiation is performed. A gas pressure measuring step for measuring, as a processing gas pressure value, a pressure of a processing gas output to the workpiece before irradiating the workpiece with a laser beam;
Using the processing gas pressure value measured at a predetermined timing set in advance from the start of output of processing gas to the workpiece until the set gas pressure is reached, the workpiece is output to the workpiece. Gas pressure determination for determining whether or not the pressure of the processing gas output to the workpiece reaches the set gas pressure after the elapse of a predetermined time after starting the output of the processing gas Steps,
When it is determined that the pressure of the processing gas reaches the set gas pressure after the predetermined time has elapsed, the beam on is used by using a time required from turning on the laser beam to irradiating the workpiece with the laser. A beam-on timing determination step for determining timing;
A laser processing step of turning on the laser beam at the determined beam-on timing and irradiating the workpiece with laser;
The laser processing method according to claim 1, comprising:   The gas pressure determining step calculates a rate of increase of the processing gas pressure value using the processing gas pressure value measured at the predetermined timing, and elapses of a predetermined time based on the calculated rate of increase of the processing gas pressure value. The laser processing method according to claim 2, wherein it is determined later whether or not the pressure of the processing gas reaches a set gas pressure. The gas pressure determining step predicts a timing at which the pressure of the processing gas reaches a gas pressure of a processing condition set in advance as a pressure arrival timing,
4. The laser processing method according to claim 2, wherein the beam-on timing determination step determines the beam-on timing using a predicted pressure arrival timing. 5. In a laser processing apparatus for performing laser processing on a workpiece by irradiating a laser beam while outputting a processing gas to the workpiece,
A gas pressure measuring unit that measures a pressure of a processing gas output to the workpiece before irradiating the workpiece with a laser beam as a processing gas pressure value;
Measured at a predetermined timing set in advance from the start of the output of the processing gas to the workpiece until the processing gas pressure reaches a preset gas pressure of the processing conditions set in advance Using the processing gas pressure value, the pressure of the processing gas output to the workpiece after the elapse of a predetermined time after starting the output of the processing gas to the workpiece is set to the set gas. A gas pressure determination unit for determining whether or not pressure is reached;
When the gas pressure determination unit determines that the pressure of the processing gas reaches the set gas pressure after the predetermined time has elapsed, the time required from when the laser beam is turned on until the workpiece is irradiated with the laser A beam on timing determination unit that determines a beam on timing to turn on the laser beam using
A laser irradiation unit that turns on the laser beam at the beam on timing determined by the beam on timing determination unit and performs laser irradiation on the workpiece; and
With
The beam-on-timing determining unit turns on the laser beam at a timing before reaching the set gas pressure, and lasers the workpiece at a timing after the timing at which the set gas pressure is reached. A laser processing apparatus, wherein the beam-on timing is determined so that irradiation is performed.   The gas pressure measurement unit measures the processing gas pressure value between a control valve that controls the pressure of the processing gas output from a processing gas supply source and the processing head. Item 6. The laser processing apparatus according to Item 5.

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