JP5756626B2 - Laser processing machine - Google Patents

Description

  The present invention relates to a laser beam machine, and more particularly to a laser beam machine capable of shortening the time lag when a workpiece is irradiated with a laser beam and improving the machining quality and machining accuracy of the workpiece.

  Conventionally, there has been known a laser processing machine configured to irradiate a workpiece such as a metal plate with a pulsed laser beam and to move the workpiece in a direction perpendicular to the optical axis of the processing head. Yes. In this laser processing machine, based on the input processing data, an arbitrary processing line (part to be processed of a workpiece) combining straight lines and curves is set in advance, and a laser beam is irradiated onto the processing line. However, the workpiece can be moved along the machining line by moving the workpiece.

  The speed at which the workpiece is moved along the processing line is decelerated at a bent portion obtained by bending a straight line or a curved line or a curved portion having a large curvature, as compared with a straight line portion or a curved portion having a small curvature. This is because the moving direction changes greatly. When the speed at which the workpiece is moved at the bent part or curved part is decelerated, if the output of the pulse laser, such as the oscillation frequency or pulse width, is fixed, the laser beam enters the bent part or curved part. Excessive heat may cause melting damage due to thermal saturation, and the heat-affected zone may become large, resulting in deterioration in processing quality. Moreover, the cutting groove width of the bent part or the curved part becomes wide, and the processing accuracy may be lowered.

  Therefore, for example, as disclosed in Patent Document 1, there is a technique for detecting the relative movement speed of the workpiece with respect to the laser beam and controlling the output of the laser beam according to the detected relative movement speed. The technique disclosed in Patent Document 1 will be described with reference to FIG. FIG. 6 is a block diagram showing an electrical configuration of a conventional laser processing machine disclosed in Patent Document 1. In FIG.

  As shown in FIG. 6, the control device 100 of the laser processing machine includes a CPU 101, a ROM 102, and a RAM 103, which are connected to an input / output port 105 via a bus line 104. The control device 100 controls the machining table moving motor 110 connected to the input / output port 105. The machining table moving motor 110 is a device that moves a machining table (not shown) to which a workpiece is fixed in a two-dimensional manner, an X-axis drive motor 110a that moves the machining table in the X-axis direction, and Y And a Y-axis drive motor 110b that moves in the axial direction. The relative movement speed detector 111 is attached to each of the X-axis drive motor 110a and the Y-axis drive motor 110b, and the movement speed in the X-axis direction and the Y-axis direction of the machining table, that is, the X-axis of the laser beam with respect to the workpiece. This is a device that detects the relative movement speed in the direction and the Y-axis direction by converting signals output from the X-axis drive motor 110a and the Y-axis drive motor 110b.

  Based on the detection signal of the relative movement speed detector 111, the speed vector calculation circuit 106 calculates a speed vector (relative movement speed), and the optimum value output circuit 107 calculates the optimum laser output and the optimum duty factor for the relative movement speed. . Based on the output signal from the optimum value calculation circuit 107, the laser output control circuit 108 controls the output of the laser oscillator 112, and the duty factor control circuit 109 controls the duty factor of the laser oscillator 112. For example, as the relative movement speed decreases, the laser beam duty factor decreases and the peak output increases, and as the relative movement speed increases, the laser beam duty factor increases and the peak output decreases. Is done.

  As described above, in the technique disclosed in Patent Document 1, since the output of the laser oscillator 112 and the duty factor are controlled based on the relative movement speed of the laser beam with respect to the workpiece, the relative movement speed is reduced. In synchronism with this, heat input by the laser beam to the bent portion or curved portion of the workpiece is suppressed, and deterioration of processing quality and processing accuracy is prevented.

Japanese Patent Laid-Open No. 62-24886

  However, in the technique disclosed in Patent Document 1, the detection of the relative movement speed of the laser beam with respect to the workpiece and the control of the laser oscillator based on the relative movement speed are complicated and time-consuming. There is a problem that the time lag until the moving speed is detected and the workpiece is irradiated with the laser beam becomes long. As a result, there may be a large deviation between the position where the laser beam is actually irradiated onto the workpiece and the preset irradiation position. When the deviation increases, the workpiece is irradiated with the laser beam while the peak output and duty factor remain the same as before the deceleration, even though the relative movement speed has been reduced, resulting in excessive heat input to the workpiece. There was sometimes. For this reason, there is a possibility that the workpiece may be melted due to heat saturation, or the heat-affected zone becomes large even if the melt does not reach, and the processing quality and processing accuracy are lowered.

  The present invention has been made to solve the above-mentioned problems, and a laser processing machine capable of shortening a time lag when a workpiece is irradiated with a laser beam and improving processing quality and processing accuracy of the workpiece. The purpose is to provide.

Means for Solving the Problems and Effects of the Invention

In order to achieve this object, according to the laser processing machine of claim 1 , both sides of the sheet-like or plate-like workpiece are held by the holding device, and the held workpiece is held by the light collecting unit. A laser beam of a pulse laser is irradiated. An X-axis stage and a Y-axis stage configured to move the light collecting unit in the X-axis direction and the Y-axis direction by moving in the X-axis direction and the Y-axis direction orthogonal to the optical axis of the machining head, and X The optical path of the laser beam in the condensing unit is changed from the optical axis of the machining head by a moving device having an X-axis linear motor and a Y-axis linear motor that move the axis stage and the Y-axis stage in the X-axis direction and the Y-axis direction, respectively. Ru is moved in orthogonal planes. The position information detection sensors disposed on the X-axis stage and the Y-axis stage respectively directly detect the position information on the X-axis and Y-axis of the X-axis stage and the Y-axis stage, and the moving distance of the light collecting unit from the position information Is acquired by the movement distance acquisition means. Moving distance obtained is determined whether the predetermined distance or more by the movement distance determination means, the result of the determination, when the moving distance obtained is the predetermined distance or more, the processing line of the workpiece by the irradiation means, predetermined A laser beam preset to a peak output and a pulse width is irradiated.

The process of acquiring the moving distance of the light collecting unit , determining whether the acquired moving distance is not less than a predetermined distance, and irradiating the laser beam when the moving distance is determined to be not less than the predetermined distance, Compared to the process of detecting the relative movement speed of the laser beam relative to the workpiece and controlling the output of the laser beam to irradiate the workpiece, the processing time can be shortened. Thereby, the time lag when the workpiece is irradiated with the laser beam can be reduced. As a result, it is possible to reduce the deviation between the position where the laser beam is actually irradiated to the workpiece and the preset irradiation position, and to prevent excessive heat input to the workpiece, This has the effect of improving the processing quality and processing accuracy of the workpiece.
Further, since the position information detection sensor can directly detect the position information of the X-axis stage and the Y-axis stage, that is, the position information of the condensing unit, the position information is converted by converting a signal output from a driving device such as a motor. Compared with the one that is indirectly detected, the detection speed of position information can be increased and the error can be reduced.
Further, when the moving distance is determined to be equal to or greater than the predetermined distance by the moving distance determining unit, the irradiation unit irradiates the laser beam preset with a predetermined peak output and pulse width by the laser generator. Compared with the case where the relative movement speed is detected and the laser beam is irradiated by changing the duty factor and the peak output according to the detected relative movement speed, the calculation time can be shortened. As a result, the time lag when the workpiece is irradiated with the laser beam can be further reduced, and there is an effect that the fine processing accuracy can be improved with a simple configuration.
In addition, since the light collecting unit is moved by the linear motor, the light collecting unit can be moved at a high speed and the positional accuracy of the light collecting unit can be ensured.

According to the laser processing machine of claim 2, the predetermined distance compared with the moving distance by the moving distance determining means is a spot diameter of the laser beam focused on the workpiece by the focusing unit (the laser beam is processed). It is set to a smaller value than the diameter of a spot created by irradiating an object. Thereby, the laser beam irradiated to the workpiece can be continued on the processing line of the workpiece by moving the optical path of the laser beam by the moving device. As a result, in addition to the effect of the first aspect, a laser-cut groove can be continuously formed along the processing line, and the heat-affected zone can be reduced by suppressing heat input by the pulse laser, thereby improving the processing quality. There is an effect that can be improved.

According to the laser processing machine of the third aspect , the movement distance is acquired by the movement distance acquisition means during the execution of the timer interruption process that is periodically executed when the movement device is in a controlled state. Since the timer interrupt process is processed preferentially, a high-speed signal can be handled. Thereby, in addition to the effect of the first or second aspect , the calculation time of the moving distance can be shortened, and the time until the workpiece is irradiated with the laser beam can be shortened.

It is a schematic diagram of the laser beam machine in one embodiment of this invention. (A) is a schematic diagram showing the movement distance ΔL, (b) is a schematic diagram showing the relationship between the position of the workpiece on the processing line and the laser output, and (c) is a processing line of the workpiece. It is a schematic diagram which shows the relationship with a spot diameter. It is a block diagram which shows the electric constitution of a laser beam machine. It is a flowchart which shows a main process. It is a flowchart which shows a timer interruption process. It is a flowchart which shows the electrical structure of the conventional laser beam machine.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments of the invention will be described with reference to the accompanying drawings. First, with reference to FIG. 1, the laser processing machine 1 in one embodiment of this invention is demonstrated. FIG. 1 is a schematic diagram of a laser beam machine 1. As shown in FIG. 1, a laser beam machine 1 includes a laser generator 10 that generates a pulse laser, a processing head 20 that irradiates a workpiece W with a pulse laser generated by the laser generator 10, and the processing head. 20 is mainly provided with a holding device 30 that holds a workpiece W to be processed by a pulsed laser irradiated from 20. The workpiece W to be subjected to laser processing is made of metal, synthetic resin, or the like formed into a sheet shape or a plate shape.

  The laser generator 10 mainly includes a laser oscillator 11 that oscillates laser light and a transmission unit 12 that transmits the laser light generated by the laser oscillator 11 to the machining head 20. In the present embodiment, the transmission unit 12 is configured by an optical fiber.

  The processing head 20 is a device that cuts the workpiece W by introducing laser light from above by the transmission unit 12, condensing the introduced laser light and irradiating the workpiece W. The processing head 20 is provided with a condensing lens, a parabolic mirror or the like (not shown) and a condensing unit 21 for condensing laser light, and oxygen or nitrogen supplied from a gas generator (not shown). An assist gas introduction hole (not shown) for introducing an assist gas composed of the above and the like into the machining head 20 and a conical cylindrical shape that is provided coaxially with the light collecting portion 21 and is arranged with the small diameter side facing the workpiece W. Nozzle (not shown). The workpiece W is irradiated with the laser beam B condensed by the condensing unit 21, and a high-speed assist gas is emitted from a nozzle (not shown) to the spot P formed by irradiating the workpiece W with the laser beam B. By jetting the gas flow, the workpiece W melted by the heat input of the laser beam B is blown off by the high-speed gas flow. As a result, the workpiece W can be cut with a minute width substantially the same as the diameter (spot diameter) of the spot P of the laser beam B.

  The condenser 21 is fixed to an X-axis stage 22 and a Y-axis stage 23 that are disposed in a plane orthogonal to the optical axis of the processing head 20. The X-axis stage 22 and the Y-axis stage 23 are configured to be movable in the X-axis direction and the Y-axis direction, respectively, by an optical path moving device 24 (see FIG. 3). In the present embodiment, the optical path moving device 24 includes an X-axis linear motor 24a that moves the X-axis stage 22 in the X-axis direction, and a Y-axis linear motor 24b that moves the Y-axis stage 23 in the Y-axis direction. Yes. By driving the optical path moving device 24, the condensing unit 21 can be moved in a plane orthogonal to the optical axis of the processing head 20, and accordingly, the optical path of the laser beam B in the condensing unit 21 is changed to the processing head 20. Is moved in a plane orthogonal to the optical axis. As a result, the spot P on which the laser beam B is focused can be moved two-dimensionally within the surface of the workpiece W. Further, since the optical path moving device 24 is constituted by a linear motor, it can be moved at a high speed and high positional accuracy can be ensured.

  The X-axis encoder 25 a and the Y-axis encoder 25 b are position information detection sensors that detect position information of the X-axis stage 22 and the Y-axis stage 23. The X-axis encoder 25 a is a sensor that detects the position of the X-axis stage 22, and the Y-axis encoder 25 b is a sensor that detects the position of the Y-axis stage 23. In the present embodiment, the X-axis encoder 25a and the Y-axis encoder 25b are configured by linear encoders that are attached to the X-axis stage 22 and the Y-axis stage 23 and directly detect the position of the linear axis. This makes it possible to increase the detection speed of position information and to eliminate error factors, as compared with the case of detecting position information indirectly by converting a signal output from a driving device such as a motor. The position information detection accuracy can be improved.

  The holding device 30 is a device that holds the workpiece W while sandwiching both sides of the workpiece W and orthogonal to the optical axis of the laser beam B. In the present embodiment, the holding device 30 is provided on an XY stage (not shown) as a moving device. The XY stage is configured to be movable in the X axis direction and the Y axis direction orthogonal to the optical axis of the laser beam B by an XY stage moving device 31 (see FIG. 3). As a result, the workpiece W held by the holding device 30 can be moved two-dimensionally within a plane perpendicular to the optical axis of the laser beam B. Further, position information of the XY stage on the X axis and the Y axis is detected by a position information detection device (not shown) including a linear encoder or the like.

  Next, referring to FIG. 2, a method for calculating the moving distance ΔL of the spot P by the XY stage moving device 31 (see FIG. 3) and the optical path moving device 24, and the spot P irradiated to the processing line S of the workpiece W And will be described. First, a method for calculating the movement distance ΔL will be described with reference to FIG. FIG. 2A is a schematic diagram showing the movement distance ΔL. Here, a method of calculating the movement distance ΔL of the X-axis stage 24a and the Y-axis stage 24b by the optical path moving device 24 will be described. In order to simplify the description, the description of the calculation method of the movement distance ΔL by the XY stage moving device 31 is omitted, but the calculation method is the same.

It is assumed that the spot P of the laser beam B condensed by the condensing unit 21 (see FIG. 1) moves at arbitrary positions a ₀ , a ₁ , a ₂ on the processing line S of the workpiece W. The position in the plane of the workpiece W can be expressed by coordinates, and the position information (coordinates) of the light collecting unit 21 when the spot P is irradiated to the positions a ₀ , a ₁ , a ₂ of the workpiece W. Is detected by the X-axis encoder 25a and the Y-axis encoder 25b. The position information (coordinates) of the position a ₀ detected by the X-axis encoder 25a and the Y-axis encoder 25b is (x ₀ , y ₀ ), the coordinates of the position a ₁ are (x ₁ , y ₁ ), and the coordinates of the position a ₂ Is (x ₂ , y ₂ ). In this case, the movement distance ΔL when the spot P moves from the position a ₁ of the workpiece W to the position a ₂ , and the movement distance ΔL when the spot moves from the position a _{1 of the} workpiece to the position a ₂ are: It is calculated by the following formula (1).

Next, the relationship between the position of the workpiece W on the processing line S and the laser output will be described with reference to FIG. FIG. 2B is a schematic diagram showing the relationship between the position of the workpiece W on the machining line S and the laser output, the horizontal axis shows the position of the workpiece W on the machining line S, and the vertical axis shows the position. Indicates the laser intensity (peak output). As described with reference to FIG. 2A, the spot P of the laser beam B condensed by the condensing unit 21 (see FIG. 1) is an arbitrary position a ₀ , a on the processing line S of the workpiece W. ₁ , ₁ , a ₂ , a ₃ , a ₄ , and a ₅ are moved sequentially. Therefore, the horizontal axis (position) in FIG. 2B includes a temporal element. In the present embodiment, a ₀ (x ₀ , y ₀ ) is the starting point of the machining line S.

Here, the movement distance when the spot P moves from the position a ₀ to the position a ₁ of the workpiece W (interval between a ₀ and a ₁ ), and the movement distance when the spot P moves from the position a ₁ to the position a _2. (distance between _{a 1} and _{a 2),} (distance between _{a 2} and _{a 3)} the movement distance when moving from the position _{a 2} to a position _{a 3,} the moving distance when moving from the position _{a 3} to position _{a 4} (The interval between a ₃ and a ₄ ), and the movement distance (the interval between a ₄ and a ₅ ) when moving from the position a ₄ to the position a ₅ is greater than or equal to a predetermined distance (threshold) set in advance. Each time it is determined, the excitation source (not shown) of the laser oscillator 11 (see FIG. 1) is pulse-controlled, and the pulse laser is output once as shown in FIG. 2 (b).

As shown in FIG. 2B, the laser beam B (see FIG. 1) that is pulsed at the positions a ₀ , a ₁ , a ₂ , a ₃ , a ₄ , and a ₅ respectively has a pulse width and a laser intensity ( (Peak output) is a preset constant value. Therefore, the calculation time can be shortened compared to the case where the relative movement speed is detected as in the prior art, and the laser beam is irradiated by changing the duty factor and the peak output according to the detected relative movement speed. As a result, the time lag when the workpiece P is irradiated with the spot P of the laser beam B can be reduced, and the fine processing accuracy can be improved with a simple configuration.

  Next, with reference to FIG. 2C, the relationship between the processing line S of the workpiece W and the diameter of the spot P (spot diameter d) will be described. FIG. 2C is a schematic diagram showing the relationship between the machining line S and the spot diameter d of the workpiece W, and the spot P moving along the machining line S is viewed together with the workpiece W in plan view.

As shown in FIG. 2 (c), the moving distance [Delta] L of the position _{a 1} from the position _{a 0} (distance between _{a 0} and _{a 1),} a moving distance [Delta] L _{(a 1} and _{a 2} position _{a 2} from the position _{a 1} interval), the moving distance [Delta] L of the position _{a 3} from position _{a 2} (distance between _{a 2} and _{a 3),} the interval between the moving distance [Delta] L _{(a 3} and _{a 4} position _{a 4} from the position _{a 3),} the position a The moving distance ΔL from ₄ to the position a ₅ (the interval between a ₄ and a ₅ ) is a value smaller than the spot diameter d. Further, in the present embodiment, each moving distance ΔL is set to a value larger than ½ of the spot diameter d. This is because a predetermined distance (threshold value), which is a condition for generating laser light by controlling an excitation source (not shown) of the laser oscillator 11 (see FIG. 1), is larger than ½ of the spot diameter d and the spot diameter. This is realized by setting a value smaller than d.

Thereby, the spot P of the laser beam B irradiated to the workpiece W can be continued on the processing line S of the workpiece W. As a result, cutting grooves can be formed by laser continuously along the processing line S, and the heat affected zone can be reduced by suppressing heat input to the workpiece W by the pulse laser, thereby improving processing quality. it can. Further, the edge of the cutting groove by the spot P can be positioned in the vicinity of the starting point a ₀ of the processing line S.

  Next, the electrical configuration of the laser processing machine 1 will be described with reference to FIG. FIG. 3 is a block diagram showing an electrical configuration of the laser processing machine 1. The laser processing machine 1 includes a control device 40 that controls the entire processing system. As illustrated in FIG. 3, the control device 40 includes a CPU 41, a ROM 42, and a RAM 43, which are connected to an input / output port 45 via a bus line 44. The input / output port 45 is connected to a device such as the optical path moving device 24.

  The CPU 41 is an arithmetic device that controls each unit connected by the bus line 44, and the ROM 42 stores control programs executed by the CPU 41 (for example, the programs in the flowcharts shown in FIGS. 4 and 5), fixed value data, and the like. This is a non-rewritable non-volatile memory to be stored. The RAM 43 is a memory for storing various data in a rewritable manner when the control program is executed. As shown in FIG. 3, a processing data memory 43a is provided.

  The machining data memory 43a is a memory that stores inputted machining data. The machining data is various data such as machining start coordinates, machining end coordinates, machining curve data and machining pattern data therebetween. The CPU 41 refers to the machining data stored in the machining data memory 43a and designates the machining line S (the part where the workpiece is machined) on the workpiece W.

  As described above, the optical path moving device 24 is configured so that the optical path in the condensing unit 21 of the laser beam B introduced from the transmission unit 12 (see FIG. 1) into the processing head 20 is in a plane orthogonal to the optical axis of the processing head 20. The X-axis linear motor 24a and the Y-axis linear motor 24b move the X-axis stage 22 and the Y-axis stage 23, to which the light collecting unit 21 is connected, in the X-axis direction and the Y-axis direction. It has.

  The XY stage moving device 31 is a device that moves an XY stage (not shown) on which a holding device 30 (see FIG. 1) for holding the workpiece W is placed in the X-axis direction and the Y-axis direction. In the present embodiment, the spot P of the laser beam B irradiated to the workpiece W from the light collecting unit 21 by the optical path moving device 24 and the XY stage moving device 31 is moved to the holding device 30 within a movable range. The workpiece W to be held can be moved to an arbitrary position.

  The X-axis encoder 25a and the Y-axis encoder 25b are position information detection sensors that detect the position information of the X-axis stage 22 (see FIG. 1) and the Y-axis stage 23. In the present embodiment, the X-axis stage 22 and the Y-axis encoder 25b The linear encoder is attached to the shaft stage 23 and directly detects the position of the linear shaft and outputs a pulse.

  The counter 26 is a detection circuit (not shown) that detects the positions of the X-axis stage 22 (see FIG. 1) and the Y-axis stage 23 by counting the output pulses of the X-axis encoder 25a and the Y-axis encoder 25b, And an output circuit (not shown) that processes the detection result and outputs the result to the CPU 41. The output of the counter 26 indicates the absolute position of the light collecting unit 21 (see FIG. 1). In other words, the coordinates x and y of the absolute position on the workpiece W of the spot P of the laser beam B irradiated from the light collecting unit 21 are shown.

  The CPU 41 collates the coordinates x and y input from the counter 26 with the processing data stored in the processing data memory 43a, and spot the laser beam B (see FIG. 1) along the specified processing line S. The X-axis linear motor 24a, the Y-axis linear motor 24b, and the XY stage moving device 31 are driven so that P moves. Further, when it is determined that the spot P of the laser beam B (see FIG. 1) is positioned on the processing line S, the CPU 41 outputs a laser output request to the pulse generator 46 (described later).

The pulse generator 46 acquires the coordinates x and y input from the counter 26, calculates the movement distance ΔL of the spot P from the acquired coordinates x and y, and the calculated movement distance ΔL is a predetermined distance (threshold). An arithmetic circuit is provided for determining whether the above is true. The movement distance ΔL is sequentially calculated by an arithmetic expression shown in Expression (2). However, x _0, y ₀ in formula (2) is x and y components of the coordinate outputting the laser pulse immediately before.

  The pulse generator 46 includes an arithmetic circuit that generates a pulse signal when the calculated movement distance ΔL is equal to or greater than a predetermined distance (threshold) and a laser output request is input from the CPU 41. This pulse signal is output to a driver (not shown) that outputs an excitation current pulse to the laser oscillator 11, and the laser oscillator 11 outputs a pulse laser according to the applied excitation current pulse.

  The other input / output device 50 shown in FIG. 3 includes an input device for inputting machining data in order to store the machining data in the machining data memory 43a, a machining line S or a spot P created based on the inputted machining data. For example, a monitor that visualizes (images) the position of the image and outputs it.

  Next, with reference to FIG. 4, main processing in the control device 40 will be described. FIG. 4 is a flowchart showing the main process. This process is a process executed by the CPU 41 while the power of the laser processing machine 1 is turned on, and is a process of moving the spot P of the laser beam B along the processing line S.

  Regarding the main process, the CPU 41 first performs an initial setting (S1). The initial setting is a process for setting the laser intensity of the laser beam output from the laser oscillator 11, a period in which a timer interrupt process (described later) is executed (hereinafter referred to as “timer interrupt period”), and the like. The timer interrupt cycle is set to a cycle shorter than the shortest cycle of the outputs of the X-axis encoder 25a and the Y-axis encoder 25b. This is because the signal processing of the X-axis encoder 25a and the Y-axis encoder 25b is performed smoothly.

  Next, the CPU 41 controls at least one of the optical path moving device 24 and the XY stage moving device 31 to spot the laser beam B along the processing line S created based on the processing data stored in the processing data memory 43a. P is moved (S2). Next, the CPU 41 determines whether or not the optical path moving device 24 and the XY stage moving device 31 are being controlled (S3). As a result, when it is determined that the optical path moving device 24 and the XY stage moving device 31 are being controlled (S3: Yes), the processing returns to S2, and the optical path moving device 24 and the XY stage moving device 31 are being controlled. If it is determined that this is not the case (S3: No), this main process is terminated.

  Next, the timer interrupt process will be described with reference to FIG. FIG. 5 is a flowchart showing the timer interrupt process. This process is a process that is started by a timer interrupt set at a predetermined cycle and repeatedly executed by the CPU 41 while the main process (see FIG. 4) is being executed. In this process, the workpiece W is irradiated with a pulse laser to perform laser processing on the workpiece W.

Regarding the timer interrupt process, the CPU 41 and the pulse generator 46 acquire the coordinates x and y input from the counter 26 (S11). The CPU 41 determines whether or not the acquired coordinates x and y are on the processing line S. If the coordinates x and y are on the processing line S, the CPU 41 outputs a laser output request to the pulse generator 46. The pulse generator 46 determines whether or not a laser output request has been started (S12). If it is determined that a laser output request has been started (S12: Yes), a pulse signal is sent to a driver (not shown). And the laser oscillator 11 is excited to output a pulse laser (S13). Next, the acquired x and y are copied to x ₀ and y ₀ in the above equation (2) (S14), and this timer interrupt process is terminated.

On the other hand, in the process of S12, when it is determined that the laser output request is not started (S12: No), it is then determined whether the laser output request is continued (S15). As a result, when it is determined that the laser output request is continued (S15: Yes), the pulse generator 46 calculates the movement distance ΔL according to the above equation (2) (S16). The pulse generator 46 determines whether or not the movement distance ΔL is greater than or equal to a predetermined distance (threshold value) stored in advance (S17), and if it is determined that the movement distance ΔL is greater than or equal to the predetermined distance (S17). S17: Yes), a pulse signal is output to a driver (not shown), and the laser oscillator 11 is excited to output a pulse laser (S13). Next, the acquired x and y are copied to x ₀ and y ₀ in the above equation (2) (S14), and this timer interrupt process is terminated.

  On the other hand, if it is determined as a result of the process of S17 that the movement distance ΔL is less than the predetermined distance (S17: No), the processes of S13 and S14 are skipped, and this timer interrupt process is terminated. Further, when it is determined that the laser output request is not continued as a result of the process of S15 (S15: No), the processes of S16 and S17 are skipped and the timer interrupt process is terminated.

  As described above, according to the embodiment of the present invention, the process of irradiating the laser beam B once is performed every time it is determined that the moving distance ΔL is equal to or greater than the predetermined distance. Since this process is simpler than the process of detecting the relative moving speed of the laser beam B with respect to the workpiece W and controlling the output of the laser beam B to irradiate the workpiece W, the processing time can be shortened. Thereby, the time lag when the spot P of the laser beam B is irradiated onto the workpiece W can be reduced. As a result, the deviation between the position where the spot P of the laser beam B is actually irradiated onto the workpiece W and the preset irradiation position can be reduced, and heat input to the workpiece W is excessive. Therefore, the processing quality and processing accuracy of the workpiece W can be improved.

  In addition, every time it is determined that the moving distance ΔL is equal to or greater than the predetermined distance, the laser beam B set in advance with a predetermined peak output and pulse width is irradiated once as shown in FIG. Compared with the case where the relative movement speed is detected and the laser beam is irradiated by changing the duty factor and the peak output according to the detected relative movement speed, the calculation time can be shortened. As a result, the time lag when the workpiece P is irradiated with the spot P of the laser beam B can be further reduced, and the fine processing accuracy can be improved with a simple configuration.

  In the main process (see FIG. 4), the timer interrupt process (see FIG. 5) is periodically executed when the moving device (the optical path moving device 24 and the XY stage moving device 31) is in a controlled state. The movement distance ΔL is acquired during the execution of the timer interruption process. Since the timer interrupt process is processed preferentially, a high-speed signal can be handled. Thereby, the calculation time of the movement distance ΔL can be shortened, and the time until the workpiece W is irradiated with the laser beam B can be shortened.

Furthermore, in the timer interruption process (see FIG. 5), when the spot P of the laser beam B is positioned on the processing line S of the workpiece W (when there is a laser output request), a pulse laser is output ( S13), coordinates x, y are copied to coordinates x ₀ , y ₀ . That is, the movement distance ΔL is calculated based on the coordinates at which the pulse laser was output immediately before. Thereby, compared with the case where movement distance (DELTA) L is acquired in the whole range of the process area | region of the workpiece W, an apparatus structure can be simplified. Furthermore, the calculation time of the movement distance ΔL can be shortened by acquiring the movement distance ΔL based on the coordinates at which the pulse laser was output immediately before. Accordingly, it is possible to shorten the time from when it is determined that the spot P of the laser beam B is positioned on the processing line S of the workpiece W to when the workpiece W is irradiated with the laser beam B.

  In the flowchart shown in FIG. 5 (timer interrupt processing), the processing of S11 and S16 is performed as the travel distance acquisition unit according to claim 1, the processing of S17 is performed as the travel distance determination unit, and the process of S13 is performed as the irradiation unit. Each process is applicable.

  The present invention has been described above based on the embodiments. However, the present invention is not limited to the above embodiments, and various improvements and modifications can be made without departing from the spirit of the present invention. It can be easily guessed. For example, the numerical values given in the above embodiment are merely examples, and other numerical values can naturally be adopted.

  In the above embodiment, the case where the transmission unit 12 that introduces laser light into the condensing unit 21 (see FIG. 1) is configured by an optical fiber has been described. Accordingly, it is naturally possible to configure the transmission unit 12 with a reflection mirror.

  In the above embodiment, the laser processing machine 1 includes both the moving device (the optical path moving device 24) that moves the light collecting unit 21 and the moving device (XY stage moving device 31) that moves the holding device 30. However, the present invention is not necessarily limited to this, and it is naturally possible to use the laser processing machine 1 including any one of the moving devices.

  In the above-described embodiment, the case where the optical path moving device 24 is configured by a linear motor and moves the light collecting unit 21 has been described. However, the present invention is not necessarily limited to this, and may be configured by another device. Examples of other devices include a piezo actuator (piezo scanner). It is also possible to adopt a method in which the light collecting unit 21 is fixed without being moved, and the spot P is moved by moving the optical path with a reflection mirror such as a galvano mirror (galvano scanner). Moreover, it is also possible to make it the structure which moves the condensing part 21 with the ball screw and nut which are rotated with a motor.

  In the above embodiment, the case where the excitation source (not shown) of the laser oscillator 11 is controlled to obtain a pulse laser has been described. However, the present invention is not limited to this, and the pulse laser is obtained by other means. Of course it is also possible. Examples of other means include means for turning on / off the laser beam output of the laser oscillator 11 with a mechanical shutter, means for obtaining a pulse waveform by switching the continuous output of the laser oscillator 11, and the like.

In the above embodiment, the case where the position information detection sensors (X-axis encoder 25a and Y-axis encoder 25b) for detecting the position information of the X-axis stage 22 and the Y-axis stage 23 are configured by linear encoders has been described. The invention is not limited to this, and it is naturally possible to use a rotary encoder or the like.
<Others>
<Means>
The laser processing machine of the technical idea 1 includes a laser generator that generates a pulse laser, a holding device that holds a workpiece irradiated with the pulse laser generated by the laser generator, and a holding device that holds the workpiece. And a processing head having a condensing unit for condensing a laser beam of a pulse laser on a processing line of the workpiece to be processed. A moving device for moving at least one of the optical path of the laser beam in the light condensing unit or the holding device in a plane perpendicular to the optical axis of the processing head while being positioned on the processing line of the workpiece, and the moving device The moving distance acquisition means for acquiring the moving distance of at least one of the optical path of the laser beam or the holding device in the condensing unit, and the moving distance A moving distance determining means for determining whether the moving distance acquired by the acquiring means is equal to or greater than a predetermined distance; and when the moving distance determining means determines that the moving distance is equal to or greater than the predetermined distance, the laser generator Irradiating means for irradiating the laser beam onto a processing line of the workpiece.
The laser processing machine according to the technical idea 2 is the laser processing machine according to the technical idea 1, wherein the predetermined distance compared with the movement distance by the movement distance determining means is focused on the workpiece by the focusing unit. It is characterized by being set to a value smaller than the spot diameter of the laser beam.
The laser processing machine according to technical idea 3 is the laser processing machine according to technical idea 1 or 2, wherein the moving device includes the light converging unit in the X-axis direction and the Y-axis direction orthogonal to the optical axis of the processing head. The X-axis stage and the Y-axis stage are configured to be movable, and the X-axis stage and the Y-axis stage are disposed on the X-axis stage and the Y-axis stage, respectively. The movement distance acquisition means acquires the movement distance of the light collecting unit based on the position information detected by the position information detection sensor, and the irradiation means A laser beam preliminarily set to a peak output and a pulse width is irradiated by the laser generator.
The laser processing machine of the technical idea 4 is the laser processing machine according to any one of the technical ideas 1 to 3, wherein the moving distance acquisition means is periodically executed when the moving device is in a controlled state. The moving distance is acquired during execution of the timer interruption process.
<Effect>
According to the laser processing machine described in the technical idea 1, the workpiece is held by the holding device, and the laser beam of the pulse laser is irradiated to the held workpiece by the condensing unit. At least one of the optical path of the laser beam or the holding device in the condensing unit is moved in a plane orthogonal to the optical axis of the processing head by the moving device, and the optical path of the laser beam or the holding device in the condensing unit moved by the moving device. At least one movement distance is acquired by the movement distance acquisition means. When the acquired moving distance is determined by the moving distance determining means to determine whether or not the acquired moving distance is greater than or equal to the predetermined distance, the laser beam is irradiated onto the processing line of the workpiece by the irradiation means. Is irradiated.
The optical path of the laser beam in the condensing unit or the moving distance of the holding device is acquired, it is determined whether the acquired moving distance is a predetermined distance or more, and the laser beam is determined when the moving distance is determined to be a predetermined distance or more. Compared to the conventional process of irradiating the workpiece by detecting the relative movement speed of the laser beam to the workpiece and controlling the output of the laser beam, the processing time can be shortened. . Thereby, the time lag when the workpiece is irradiated with the laser beam can be reduced. As a result, it is possible to reduce the deviation between the position where the laser beam is actually irradiated to the workpiece and the preset irradiation position, and to prevent excessive heat input to the workpiece, This has the effect of improving the processing quality and processing accuracy of the workpiece.
According to the laser processing machine described in the technical idea 2, the predetermined distance compared with the moving distance by the moving distance determining means is the spot diameter of the laser beam focused on the workpiece by the focusing unit (the laser beam is covered by the laser beam). It is set to a smaller value than the diameter of the spot created by irradiating the workpiece. Thereby, the laser beam irradiated to the workpiece can be linked on the processing line of the workpiece by moving the optical path of the laser beam or the holding device by the moving device. As a result, in addition to the effect of the technical idea 1, it is possible to continuously form a cutting groove by a laser along the processing line, and to reduce the heat-affected zone by suppressing the heat input by the pulse laser, so that the processing quality can be reduced. There is an effect that can be improved.
According to the laser processing machine described in the technical idea 3, the moving device is an X-axis stage and a Y-axis stage configured to be able to move the condensing unit in the X-axis direction and the Y-axis direction orthogonal to the optical axis of the processing head. The laser processing machine includes a position information detection sensor that is disposed on each of the X-axis stage and the Y-axis stage and directly detects position information on the X-axis and the Y-axis of the X-axis stage and the Y-axis stage. ing. The position information detection sensor can directly detect the position information of the X-axis stage and the Y-axis stage, that is, the position information of the light collecting unit. Therefore, the detection speed of the position information can be increased and the error can be reduced as compared with the case where the position information is detected indirectly by converting a signal output from a driving device such as a motor.
Further, when the moving distance is determined to be equal to or greater than the predetermined distance by the moving distance determining unit, the irradiation unit irradiates the laser beam preset with a predetermined peak output and pulse width by the laser generator. Compared with the case where the relative movement speed is detected and the laser beam is irradiated by changing the duty factor and the peak output according to the detected relative movement speed, the calculation time can be shortened. As a result, in addition to the effects of the technical idea 1 or 2, the time lag when the workpiece is irradiated with the laser beam can be further reduced, and the fine processing accuracy can be improved with a simple configuration.
According to the laser processing machine described in the technical idea 4, the movement distance is acquired by the movement distance acquisition unit during the execution of the timer interruption process that is periodically executed when the movement device is in a controlled state. . Since the timer interrupt process is processed preferentially, a high-speed signal can be handled. Thereby, in addition to the effect described in any one of the technical ideas 1 to 3, there is an effect that the calculation time of the movement distance can be shortened and the time until the workpiece is irradiated with the laser beam can be shortened.

1 Laser processing machine 11 Laser oscillator (part of laser generator)
12 Transmitter (part of laser generator)
20 Processing Head 21 Condenser 22 X-axis Stage 23 Y-axis Stage 24 Optical Path Moving Device (Moving Device)
24a X-axis linear motor
24b Y-axis linear motor 25a X-axis encoder (position information detection sensor)
25b Y-axis encoder (position information detection sensor)
30 Holding device 31 XY stage moving device (moving device)
B Laser beam d Spot diameter P Spot S Processing line W Workpiece

Claims (3)

A laser generator that generates a pulse laser, a holding device that holds both sides of a sheet-like or plate-like workpiece irradiated with the pulse laser generated by the laser generator, and a workpiece that is held by the holding device In a laser processing machine comprising a processing head having a condensing unit that condenses a laser beam of a pulse laser on a processing line of a workpiece,
An X-axis stage and a Y-axis stage configured to be movable in the X-axis direction and the Y-axis direction by moving the X-axis direction and the Y-axis direction orthogonal to the optical axis of the processing head, respectively; A spot of a laser beam that has an X-axis linear motor and a Y-axis linear motor that move the X-axis stage and the Y-axis stage in the X-axis direction and the Y-axis direction, respectively, and is irradiated onto the workpiece by the focusing unit A moving device that moves the optical path of the laser beam in the condensing unit within a plane orthogonal to the optical axis of the processing head, while positioning the workpiece on the processing line of the workpiece,
A position information detection sensor that is disposed on each of the X-axis stage and the Y-axis stage, and directly detects position information on the X-axis and the Y-axis of the X-axis stage and the Y-axis stage;
A movement distance acquisition means for acquiring a movement distance of the light collecting unit based on position information detected by the position information detection sensor ;
A moving distance determining means for determining whether the moving distance acquired by the moving distance acquiring means is a predetermined distance or more;
When the moving distance determining means determines that the moving distance is greater than or equal to a predetermined distance, the laser generator preliminarily sets a predetermined peak output and pulse width on the processing line of the workpiece. A laser processing machine comprising: irradiation means for irradiating a beam.   The predetermined distance compared with the moving distance by the moving distance determining means is set to a value smaller than the spot diameter of the laser beam focused on the workpiece by the focusing unit. The laser processing machine described. The movement distance acquiring means, according to claim 1 or 2, characterized in that the mobile device during execution of the timer interrupt processing to be performed periodically when in a condition to be controlled, to obtain the moving distance The laser beam machine described in 1.