JP7375634B2 - Laser processing system and laser processing method - Google Patents

Description

The present invention relates to a laser processing system and a laser processing method.

Conventionally, laser processing machines are used for cutting, welding, etc. of workpieces. In such a laser processing machine, from the viewpoint of improving the processing quality of the workpiece, a technique is known in which the processing state is grasped (monitored) from a captured image obtained by capturing an image of the workpiece being processed. Patent Document 1 discloses a technique for arranging a plurality of laser elements in an array and imaging a work illuminated by illumination lasers emitted by the outputs of the plurality of laser elements.

JP 2017-192983 Publication

Parts cut out from a work by a laser processing machine may then be picked by a loader device. Here, the loader device may stop operating because it cannot pick parts that have not been properly cut out from the workpiece. Furthermore, even if the loader device is able to pick a part that has not been properly cut out from the workpiece, it is not a part that can be used in the subsequent process, so there is a high possibility that the flow will be stopped in one of the subsequent processes.

An object of the present invention is to provide a laser machining system and a laser machining method that can suppress the influence on post-processes caused by cutting defects in cutting a workpiece.

A laser processing system according to an aspect of the present invention is a laser processing system that includes a laser processing machine that laser-processes a plate-shaped workpiece to cut out parts, and includes a laser head that irradiates the workpiece with a processing laser; an imaging unit that images the cut part of the workpiece irradiated with the laser; a detection unit that detects a cutting defect based on the image obtained by the imaging unit; and a workpiece that surrounds the cutting line of the defective part. and a control unit that moves the laser head along the above predetermined path while irradiating the processing laser.

Further, the detection unit may detect a cutting defect based on one or both of the kerf width on the workpiece in the image and information regarding reflected light from the surface of the workpiece in the image. Further, the predetermined route may be rectangular in plan view. Further, each of the four sides of the predetermined path of the rectangle may be set so that, in plan view, a part of the cutting line of the defective part overlaps or a part of the cutting line is in the vicinity. . Further, one side of the rectangular predetermined path may be parallel to the outer edge of the workpiece. Further, the predetermined path may be set so as not to overlap the cutting lines of adjacent parts in the workpiece. Furthermore, when the detection section detects a cutting defect, the control section may stop cutting out the defective part and move the laser head while irradiating the processing laser along a predetermined path. In addition, a first program for actual machining to cut out parts and a second program for moving the laser head while irradiating the machining laser along a predetermined path are created in advance, and the control unit is configured to control the processing of the first program. If the detection unit detects a cutting defect during execution, execution of the first program may be stopped and the second program may be executed. Further, the control unit may move the laser head while irradiating the processing laser along a predetermined path at a speed slower than the speed at which the parts are cut out. Further, the cutting line indicated by the above-mentioned predetermined route may have a portion that overlaps with the cutting line of the part. Further, it may include a loader device that picks the cut out parts and the defective parts cut out along the cutting line indicated by the predetermined path.

A laser processing method according to an aspect of the present invention is a laser processing method in a laser processing system having a laser processing machine for cutting out parts by laser processing a plate-shaped workpiece, in which a laser head is connected to a processing laser beam on the workpiece. irradiate the workpiece with the processing laser, take an image of the cut part of the workpiece that has been irradiated with the processing laser, detect a cutting defect based on the image obtained by imaging, and trace the cutting line of the defective part. This includes moving the laser head along a predetermined path on the surrounding work while irradiating the processing laser.

According to the laser processing system and the laser processing method according to aspects of the present invention, it is possible to suppress the influence on post-processes caused by cutting defects during cutting of a workpiece.

In a configuration in which the detection unit detects a cutting defect based on one or both of the kerf width on the workpiece in the image and the information regarding the reflected light from the surface of the workpiece in the image, it is possible to detect the cutting defect with high accuracy. can. Further, in a configuration in which the predetermined path is rectangular in plan view, the load on the laser processing machine during cutting can be suppressed, and cutting can be performed quickly. Furthermore, in a configuration in which each of the four sides of a predetermined path of a rectangle is set so that, in plan view, a part of the cutting line of the defective part overlaps or a part of the cutting line is in the vicinity. By reducing the area inside the predetermined path, cutting can be performed more quickly. Further, in a configuration in which one side of the rectangular predetermined path is parallel to the outer edge of the workpiece, the predetermined path can be easily set. Furthermore, in a configuration in which the predetermined path is set so as not to overlap the cutting line of adjacent parts of the workpiece, it is possible to avoid cutting adjacent parts when the workpiece is cut along the predetermined path. In addition, in a configuration in which the control unit stops cutting out the defective part when the detection unit detects a cutting defect and moves the laser head while irradiating the processing laser along a predetermined path, the laser processing The load on the machine can be suppressed and cutting can be performed quickly. In addition, a first program for actual machining to cut out parts and a second program for moving the laser head while irradiating the machining laser along a predetermined path are created in advance, and the control unit controls the processing of the first program. In a configuration in which when the detection unit detects a cutting defect during execution, execution of the first program is stopped and the second program is executed, the influence on subsequent processes caused by cutting defects during cutting of the workpiece is suppressed. can do. Further, in a configuration in which the control unit moves the laser head while irradiating the processing laser along a predetermined path at a speed slower than the speed at which the parts are cut out, the cutting process along the predetermined path can be more reliably completed. Further, in a configuration in which the cutting line indicated by the above-mentioned predetermined route has a portion where it overlaps with the cutting line of the parts, it is possible to maintain cutting out of a larger number of parts. Further, in a configuration including a loader device that picks the cut out parts and the defective parts cut out along the cutting line indicated by the predetermined path, it is possible to suppress the influence on the subsequent process due to cutting defects in the cutting process of the workpiece.

FIG. 1 is a diagram showing an example of a laser processing machine according to an embodiment. FIG. 2 is a diagram showing an example in which a part of the laser processing machine shown in FIG. 1 is shown in cross section. It is a block diagram showing an example of composition of a processing device provided in a laser processing machine. FIG. 3 is a diagram illustrating an example of a machining program. 1 is a flowchart illustrating an example of a laser processing method according to an embodiment. It is a figure showing an example of a flow of laser processing processing. 7 is a diagram showing an example of the flow of laser processing processing following FIG. 6. FIG. 8 is a diagram illustrating an example of the flow of laser processing processing following FIG. 7. FIG. 9 is a diagram showing an example of the flow of laser processing processing following FIG. 8. FIG. 10 is a diagram showing an example of the flow of laser processing processing following FIG. 9. FIG. 11 is a diagram showing an example of the flow of laser processing processing following FIG. 10. FIG. 12 is a diagram showing an example of the flow of laser processing processing following FIG. 11. FIG. 13 is a diagram illustrating an example of the flow of laser processing processing following FIG. 12. FIG.

Hereinafter, embodiments will be described with reference to the drawings. Note that the present invention is not limited to the form described below. Further, in the drawings, in order to explain the embodiments, the scale may be changed as appropriate, such as enlarging, reducing, or emphasizing a portion. In each figure, directions in the figure may be explained using an XYZ orthogonal coordinate system. In the XYZ orthogonal coordinate system, the vertical direction is the Z direction, and the horizontal directions are the X and Y directions. Further, in each direction (eg, the X direction), the direction of the arrow is referred to as the + side (eg, the +X side), and the side opposite to the direction of the arrow is referred to as the − side (eg, the −X side).

FIG. 1 is a diagram showing an example of a laser processing machine according to an embodiment, and FIG. 2 is a diagram showing an example in which a part of the laser processing machine shown in FIG. 1 is shown in cross section. The laser processing machine 100 can cut a plate-shaped workpiece W to be processed by irradiating a laser beam L1. Laser processing machine 100 is included in laser processing system 1 . The laser processing machine 100 performs laser processing (cutting processing) on the work W carried into the processing area to cut out parts. Loading of the unprocessed workpiece W into the laser processing machine 100 and removal of processed parts may be performed by a loader device 80 (see FIG. 13) included in the laser processing system 1, or may be performed by the processing pallet 50. It's okay to be hurt. Note that the laser processing machine 100 may be, for example, a multifunction machine in which another processing device such as a punch press is arranged adjacently.

As shown in FIGS. 1 and 2, the laser processing machine 100 includes a laser head 10, a head drive section 20, a lens drive section 21, an imaging section 30, a processing device 40, and a processing pallet 50. The laser head 10 includes, for example, a head main body 11 and a nozzle 12, and irradiates the workpiece W with a processing laser. Specifically, the laser head 10 cuts the workpiece W by irradiating the workpiece W with a laser beam L1, which is a processing laser, from the upper surface Wa side, and cuts out the part P from the workpiece W. When cutting a part P from a workpiece W, a laser beam L1 is irradiated outward from the part P to form a through hole (piercing hole) H, and the laser beam L1 is directed from the through hole H to the cutting line of the part P. move it to. Next, the part P is cut out from the workpiece W by moving the laser beam L1 along the cutting line of the part P. The laser head 10 is connected to a laser light source such as a laser oscillator 60.

The laser oscillator 60 generates, for example, an infrared laser beam as a processing laser (laser beam L1). Note that the laser light source may be, for example, a carbon dioxide laser light source or a solid state laser light source. The laser head 10 has an irradiation optical system 61. The irradiation optical system 61 converges the laser beam L1 generated by the laser oscillator 60. The irradiation optical system 61 includes, for example, an optical fiber 62, a collimator 63, a beam splitter 64, and a condenser lens 65. The optical fiber 62 has one end (the end on the light input side) connected to the laser oscillator 60 and the other end (the end on the light output side) connected to the laser head 10 . Laser light L1 from laser oscillator 60 is introduced into laser head 10 via optical fiber 62.

The collimator 63 converts the laser beam L1 from the laser oscillator 60 into parallel light or makes it close to parallel light. The collimator 63 is arranged, for example, so that the focal point on the light input side coincides with the position of the end of the optical fiber 62 on the light output side. The beam splitter 64 is arranged at a position where the laser beam L1 that has passed through the collimator 63 is incident. The beam splitter 64 is a wavelength selection mirror (for example, a dichroic mirror) having a characteristic that the laser beam L1 is reflected and the illumination laser L2 described later is transmitted. The beam splitter 64 is arranged at an angle of about 45 degrees with respect to the optical axis 63a of the collimator 63. The beam splitter 64 is tilted toward the +X side as it goes toward the +Z side.

The condensing lens 65 is arranged at a position where the laser beam L1 from the beam splitter 64 is incident. The laser beam L1 that has passed through the collimator 63 is reflected by the beam splitter 64, its optical path is bent by about 90 degrees from the X direction to the Z direction (-Z side), and enters the condenser lens 65. The condensing lens 65 condenses the laser beam L1 from the collimator 63. The condensing lens 65 is movable along the optical axis 65a of the condensing lens 65.

The nozzle 12 irradiates the laser beam L1 focused by the irradiation optical system 61. The laser head 10 irradiates the work W with the laser light L1 so as to form a spot LS of a predetermined diameter on the workpiece W by irradiating the laser light L1 converged by the irradiation optical system 61 from the nozzle 12 . The diameter of the spot LS can be adjusted, for example, by moving some of the optical elements (for example, the condensing lens 65) of the irradiation optical system 61. The diameter of the spot LS increases as the focal point of the irradiation optical system 61 moves away from the surface of the workpiece W (as the amount of defocus increases). The laser processing machine 100 changes the width of the cutting groove (kerf width, cutting width) on the workpiece W formed by the laser beam L1 by changing the diameter of the spot LS of the laser beam L1 on the surface of the workpiece W. .

The nozzle 12 is attached below the head body 11 (-Z side). The nozzle 12 is oriented in the -Z direction (downward) and irradiates the laser beam L1 from the head body 11 in the -Z direction (downward). The nozzle 12 is connected to an assist gas supply unit (not shown) via a gas supply pipe or the like, and supplies assist gas from the assist gas supply unit to the workpiece W toward an area (processing area) to which the laser beam L1 is irradiated. do. As a supply source of the assist gas, for example, a gas cylinder, a supply line of a factory, etc. are used. As the assist gas, for example, nitrogen gas, air, a mixed gas of nitrogen and oxygen, etc. are used.

The head main body 11 is arranged above the workpiece W (on the +Z side) arranged in the processing area within the laser processing machine 100. The head main body 11 is movable in the X direction, the Y direction, and the Z direction under the control of the head drive section 20. The head main body 11 is moved relative to the work W by, for example, being moved under the control of the head drive section 20. Note that the cutting of the workpiece W is not limited to being realized by moving the head main body 11. In cutting the workpiece W, for example, the workpiece W (processing pallet 50) may be moved relative to the head body 11, or both the head body 11 and the workpiece W may be moved. good.

The head drive section 20 moves the laser head 10 in the X direction, Y direction, and Z direction under the control of the processing device 40. The head driving section 20 includes, for example, a gantry that is movable in the X direction, a slider that is movable in the Y direction with respect to the gantry, and an elevating section that is movable in the Z direction with respect to the slider. The head driving section 20 moves the laser head 10 to predetermined positions in the X direction, Y direction, and Z direction by driving respective drive sources of the gantry, slider, and elevating section. Note that the head drive unit 20 is not limited to the above configuration, and may be realized by other configurations such as a robot arm. The lens drive unit 21 adjusts the focus of the light emitted from the nozzle 12 under the control of the processing device 40 . The lens drive unit 21 can adjust the focal point of the irradiation optical system 61 on the workpiece W side by moving the condenser lens 65 along the optical axis 65a of the condenser lens 65. That is, the diameter of the spot LS of the laser beam L1 on the surface of the workpiece W changes as the condensing lens 65 is moved under the control of the lens driving section 21.

The laser processing machine 100 images the work W while illuminating the work W with the illumination laser L2. The laser array 70 includes a plurality of laser elements arranged in an array as an illumination laser L2, and uses the outputs of the plurality of laser elements to emit light of a different wavelength from that of the processing laser (laser light L1). emanate. Each of the plurality of laser elements is, for example, a vertical cavity surface emitting laser (VCSEL). Further, the laser array 70 is configured as an illumination unit 73 (stored in a housing of the illumination unit 73) together with a part of the illumination optical system 71 (for example, the collimator 72, etc.). The illumination unit 73 may be detachably connected to the laser head 10.

The illumination optical system 71 illuminates the work W with the illumination laser L2 generated by the laser array 70. The illumination optical system 71 includes, for example, a collimator 72, a half mirror 74, a beam splitter 64, and a condenser lens 65. The illumination optical system 71 shares a beam splitter 64 and a condensing lens 65 with the irradiation optical system 61, and performs epi-illumination via the condensing lens 65. The optical axis 72a on the light output side of the illumination optical system 71 and the optical axis 63a on the light output side of the irradiation optical system 61 are coaxial, and the illumination laser L2 passes through the same optical path as the laser beam L1 to illuminate the workpiece. W is irradiated. Further, the illumination optical system 71 has a focal point on the illumination side and a focal point on the workpiece W side where light emitted from the focal point on the illumination side is focused via the illumination optical system 71, and these focal points are optically They are in a conjugate positional relationship. Therefore, for example, by setting the focus on the workpiece W side on the surface of the workpiece W and arranging the light source at the position of the corresponding focus on the illumination side, light can be focused on the surface of the workpiece W via the illumination optical system 71.

The collimator 72 is arranged at a position where the illumination laser L2 from the laser array 70 is incident. The collimator 72 converts the illumination laser L2 from the laser array 70 into parallel light or makes it close to parallel light. When adjusting the focus of the illumination optical system 71 on the workpiece W side to the target position of the workpiece W, the collimator 72 is arranged such that the focus on the illumination side coincides with the position of the laser array 70, for example.

The half mirror 74 is arranged at a position where the illumination laser L2 that has passed through the collimator 72 is incident. The half mirror 74 is a reflective/transmissive member having a characteristic of partially reflecting the illumination laser L2 and partially transmitting the illumination laser L2. The half mirror 74 is set, for example, so that the ratio of transmitted light of the illumination laser L2 is about 50%, and the ratio of reflected light is about 50%. The half mirror 74 is arranged to be inclined at an angle of about 45 degrees with respect to the optical axis 72a of the collimator 72. The half mirror 74 is tilted toward the −X side as it goes toward the +Z side.

A part of the illumination laser L2 that has passed through the collimator 72 is reflected by the half mirror 74, the optical path is bent by about 90 degrees from the X direction to the Z direction (-Z side), and enters the beam splitter 64. As described above, the half mirror 74 is tilted in one direction (eg, in the direction toward the -X side as it goes toward the +Z side) with respect to the optical axis 65a of the condenser lens 65. The beam splitter 64 is tilted in a direction opposite to the direction in which the half mirror 74 is tilted with respect to the optical axis 65a of the condenser lens 65 (for example, in a direction toward the +X side as it goes toward the +Z side). The optical path of the light transmitted through the beam splitter 64 and the half mirror 74 is shifted due to refraction at the beam splitter 64, and the optical path is shifted due to refraction at the half mirror 74.

The condensing lens 65 is arranged at a position where the illumination laser L2 enters from the beam splitter 64. Further, the condensing lens 65 condenses the laser beam L1 from the beam splitter 64. The illumination area on the workpiece W that is irradiated with the illumination laser L2 is set to include the irradiation area (processing area) on the workpiece W that is irradiated with the laser beam L1. Further, the laser array 70 and the illumination optical system 71 are configured such that the projection area of the laser array 70, which is determined based on the size of the laser array 70 and the optical magnification of the illumination optical system 71, includes the entire area of the emission aperture of the nozzle 12. Ru.

The imaging unit 30 images the cut portion of the workpiece W irradiated with the processing laser (laser light L1). The imaging unit 30 includes, for example, an imaging optical system 31 and an imaging element 32, and the imaging element 32 detects light (return light) from the workpiece W via the imaging optical system 31. The image sensor 32 is, for example, a CCD or CMOS image sensor, and captures the image formed by the imaging optical system 31. The image sensor 32 is provided with a plurality of pixels arranged two-dimensionally. Furthermore, each pixel is provided with a light receiving element such as a photodiode. The image sensor 32 sequentially reads charges (signals) generated in each pixel when light (return light) enters the light receiving element, amplifies the read signals, A/D converts them, and arranges them in an image format. , generate digital data of the captured image.

The imaging optical system 31 includes a condensing lens 65, a beam splitter 64, a half mirror 74, a wavelength selection filter 33, and an imaging lens 34. The imaging optical system 31 and the illumination optical system 71 share a condensing lens 65, a beam splitter 64, and a half mirror 74. The imaging unit 30 is capable of imaging the workpiece W coaxially with the illumination optical system 71.

The image sensor 32 is held by, for example, an alignment device 35, and its position with respect to the imaging optical system 31 can be adjusted by the alignment device 35. For example, if the focal point (image plane position) of the imaging optical system 31 deviates from the image sensor 32 in a direction parallel to the optical axis 34a of the imaging lens 34 (X direction), the alignment device 35 moves the image sensor 32. By doing so, the position of the image sensor 32 can be aligned with the focus of the imaging optical system 31.

The return light from the workpiece W passes through the condenser lens 65 and enters the beam splitter 64 . The returned light includes, for example, the light of the illumination laser L2 that is reflected and scattered by the workpiece W, and the light of the laser beam L1 that is reflected by the workpiece W. Of the returned light that has entered the beam splitter 64, the light that originates from the illumination laser L2 passes through the beam splitter 64 and enters the half mirror 74. Furthermore, among the returned light that has entered the beam splitter 64, the light that originates from the laser beam L1 is reflected by the beam splitter 64 and removed from the optical path from the beam splitter 64 toward the half mirror 74.

When molten metal, which is obtained by melting the workpiece W by irradiation with the laser beam L1, is present on the surface of the workpiece W, the returned light includes light emitted from the molten metal in a wavelength range from red to near-infrared. Further, when plasma is generated due to melting and evaporation of the workpiece W by irradiation with the laser beam L1, the returned light includes light in a wavelength range from blue to ultraviolet. Among the light caused by molten metal or plasma, light having a wavelength different from that of the laser light L1 passes through the beam splitter 64 and enters the half mirror 74.

The returned light that has entered the half mirror 74 is divided into light that passes through the half mirror 74 and enters the wavelength selection filter 33, and light that is reflected by the half mirror 74. The wavelength selection filter 33 has a characteristic of reflecting light in a wavelength band that is reflected by the workpiece W by illumination by the illumination laser L2. Further, the wavelength selection filter 33 has a characteristic of transmitting light in a wavelength band emitted from the workpiece W by irradiation with the laser beam L1. The wavelength selection filter 33 is, for example, a dichroic mirror or a notch filter. That is, among the returned light, the light originating from the illumination laser L2 is reflected by the wavelength selection filter 33 and enters the imaging lens 34. As a result, disturbance light included in the returned light can be blocked, thereby improving the S/N ratio of the image. The imaging lens 34 focuses the light reflected by the wavelength selection filter 33 onto the image sensor 32 . The imaging lens 34 and the condensing lens 65 project an image of the workpiece W (the cut portion of the workpiece W) onto the imaging element 32 . The imaging unit 30 mainly generates digital data of a captured image according to light (return light) in a wavelength band reflected by the workpiece W by illumination by the illumination laser L2.

The processing device 40 centrally controls the laser processing machine 100 and controls the operations of the laser head 10, head drive section 20, lens drive section 21, imaging section 30, and the like. The processing device 40 includes, for example, a detection section 41 and a control section 42. The detection unit 41 detects cutting defects based on the captured image obtained by the imaging unit 30 . The control unit 42 moves the laser head 10 along a predetermined path on the workpiece W that surrounds (includes) the cutting line of the defective part while irradiating the processing laser (laser light L1). Note that details of the processing in the processing device 40 will be described later.

The processing pallet 50 places the work W on it and arranges the work W in the processing area within the laser processing machine 100. The processing pallet 50 may be movable in the X direction or the like with the workpiece W placed thereon, for example, by a drive device (not shown). The processing pallet 50 has a base plate 51 and a support plate 52. A plurality of support plates 52 are arranged in a row on the upper surface (+Z side surface) of the base plate 51, and support the lower surface (−Z side surface) Wb of the workpiece W. Each support plate 52 has a plurality of upper end portions 52a formed in a sawtooth shape, and the upper end portions 52a are formed to have the same height.

Workpieces W are placed on the plurality of upper end portions 52a. The contact area between the upper end portion 52a and the workpiece W is small because the upper end portion 52a is formed in a sawtooth shape. Note that the upper end portion 52a is not limited to a sawtooth shape, and may be, for example, a serpentine shape or a wavy shape. Further, the processing pallet 50 may be, for example, a pallet in which a plurality of pins are arranged on the base plate 51. Note that it is optional whether or not to use the processing pallet 50. For example, instead of the processing pallet 50, a workpiece mounting portion such as a crest shape may be provided in the processing area within the laser processing machine 100. In addition, when the laser processing machine 100 is a multifunction machine with a turret punch press adjacent to it, the multifunction machine has a fixed laser head (similar to the laser head 10 shown in FIG. ) and a fixed punch head for forming, etc.

FIG. 3 is a block diagram showing a configuration example of a processing device according to an embodiment. The processing device 40 includes a detection section 41 , a control section 42 , an acquisition section 43 , a storage section 44 , and a communication section 45 . As described above, the detection unit 41 detects cutting defects based on the captured image obtained by the imaging unit 30. Specifically, the detection unit 41 acquires a captured image from the imaging unit 30, and obtains information regarding the kerf width on the workpiece W in the acquired captured image and the reflected light (return light) from the surface of the workpiece W in the captured image. A cutting defect in the part being cut out is detected based on one or both of the following. As described above, the captured image acquired from the imaging unit 30 includes the cut portion of the workpiece W irradiated with the laser beam L1.

For example, the detection unit 41 uses the captured image to measure the kerf width in the cutting process of the workpiece W by the laser beam L1. In measuring the kerf width using the captured image, the detection unit 41 detects the position of the edge corresponding to the edge of the cut groove by laser processing, and then measures the distance (e.g., in pixel units) between the edges on the captured image. Convert to scale distance (e.g., in mm). Then, the detection unit 41 compares the measured kerf width with a normal value of the kerf width corresponding to the cutout of the corresponding part. At this time, the detection unit 41 detects that a cutting defect has occurred in the part being cut out if the measured kerf width is outside a predetermined threshold range that includes a normal value.

For example, the detection unit 41 uses the captured image to calculate intensity information (eg, brightness value, pixel value, pixel intensity, gradation value, etc.) that is information regarding the return light from the surface of the workpiece W. Then, after calculating the intensity information of the returned light, the detection unit 41 compares the normal value of the intensity information corresponding to the cutout of the corresponding part. At this time, the detection unit 41 detects that a cutting defect has occurred in the part that is being cut out if the calculated intensity information of the returned light is outside a predetermined threshold range that includes a normal value. . That is, the fact that the intensity information of the returned light deviates from the predetermined threshold range including the normal value indicates that an abnormal amount of molten metal has adhered to the surface of the workpiece W due to the irradiation with the laser beam L1, or that the workpiece W has been cut. This includes the fact that it has not been processed. As described above, the detection unit 41 detects the part being cut out based on one or both of the detection of cutting defects according to the kerf width and the detection of cutting defects according to the intensity information of the returned light. It is sufficient to detect cutting defects.

The control unit 42 centrally controls the laser processing machine 100 and controls the operations of the laser head 10, head drive unit 20, lens drive unit 21, imaging unit 30, and the like. Further, as described above, the control unit 42 moves the laser head 10 while irradiating the processing laser (laser light L1) along a predetermined path on the workpiece W surrounding the cutting line of the part that has failed to be cut. let For example, when cutting out parts from the workpiece W, the laser processing machine 100 moves the laser head 10 while irradiating the laser beam L1 along the cutting line. In this embodiment, the cutting line includes a cutting line for cutting out parts from the workpiece W and a cutting line indicated by a predetermined path. Cutting along the cutting line indicated by the predetermined path is performed in order to prevent parts that cannot be used in the subsequent process from being transported (stopping the flow in the subsequent process). In addition, when cutting along a cutting line indicated by a predetermined path, at least the cut parts (defective parts) are picked by the loader device 80 (see FIG. 13) and transported to a predetermined location (e.g., product pallet 90). It is assumed that it is possible.

The shape of the cutting line indicated by the predetermined route is, for example, a rectangle (including a square) in plan view. By making the shape of the cutting line indicated by the predetermined path into a rectangle, the load applied to the laser processing machine 100 during cutting can be suppressed and the cutting can be performed more quickly than when cutting along a complicated path. Also, for example, each of the four sides of the predetermined path of the rectangle is set so that, in plan view, a part of the cutting line of the defective part overlaps or a part of the cutting line is nearby. be done. As a result, the area inside the rectangular predetermined path can be reduced (minimized). By reducing the area inside the predetermined path, parts (defective parts) can be quickly cut out. Furthermore, one side of the rectangular predetermined path may be parallel to the outer edge of the rectangular workpiece W, for example. By making one side of the predetermined path parallel to the outer edge of the workpiece W, the predetermined path can be easily set. Moreover, when cutting out a plurality of parts from the workpiece W, it is preferable to cut out more parts. That is, the intervals between each part may be set narrower. Therefore, the cutting line indicated by the predetermined path may overlap the cutting line for cutting out parts from the workpiece W. By having a portion where the cutting line indicated by the predetermined path and the cutting line for cutting out parts from the workpiece W overlap, it is possible to maintain cutting out of more parts. Further, for example, the predetermined path is set so as not to overlap the cutting lines of adjacent parts in the workpiece W. With this setting, when a workpiece is cut along a predetermined path, it is possible to avoid cutting an adjacent part, and it is possible to use an adjacent part as a proper part.

For example, when the detection unit 41 detects a cutting defect in a part that is being cut out, the control unit 42 stops cutting out the defective part and uses a processing laser (laser) along the above-mentioned predetermined path. Control is performed to move the laser head 10 while irradiating the light L1). That is, when the detection unit 41 detects a cutting defect, the control unit 42 controls the part to stop cutting out the defective part and perform cutting along a predetermined path. In this embodiment, if a part is cut out poorly, the part is cut along a predetermined path surrounding the cutting line of the part, so that the part can be transported while suppressing the influence on subsequent processes. For example, even if the cutting of parts is completed with poor cutting, picking by the loader device 80 or the like may not be performed appropriately, which is not preferable. As described above, the control unit 42 stops cutting out the parts when a cutting defect is detected and shifts to cutting along a predetermined path, thereby suppressing the influence on the subsequent process (transportation of the parts). ing.

Regarding the movement of the laser head 10 along the predetermined path, the control unit 42 causes the processing laser (laser light L1) to irradiate the processing laser (laser light L1) along the predetermined path at a speed slower than the cutting speed of the part in which the cutting defect has been detected. It is preferable to perform control to move the laser head 10 at the same time. As one aspect, the cutting failure of the workpiece W is caused by the cutting speed relative to the material and thickness of the workpiece W. That is, the defective cutting of the workpiece W is caused by the fact that the amount of irradiation of the laser beam L1 to the workpiece W becomes insufficient if the speed of cutting out the parts is fast (inappropriate). Therefore, when the control unit 42 controls the cutting process to be performed along the predetermined path, the control unit 42 performs the cutting process at a slower speed than when the cutting defect is detected, so that the cutting process using the predetermined path can be more reliably completed. .

The control of the cutting process described above is realized by executing a process program. That is, in this embodiment, a first program for actual processing to cut out parts and a second program for moving the laser head 10 while irradiating the processing laser (laser light L1) along a predetermined path are created in advance. has been done. The first program and the second program are created in advance by, for example, a device equipped with CAM or CAD/CAM.

FIG. 4 is a diagram illustrating an example of a machining program according to the embodiment. As machining programs created by CAM or the like, a first program and a second program are prepared for each part cut out from the workpiece W. Moreover, when the parts cut out from the workpiece W have the same shape, the machining program may be prepared as a first program and a second program that perform loop processing as many times as the parts cut out from the workpiece W.

For example, when the detection unit 41 detects a cutting failure while executing the first program, the control unit 42 stops execution of the first program and executes the second program. If a first program and a second program are prepared for each part to be cut out from the workpiece W, the control unit 42 sequentially executes the first program corresponding to the part, and if the part is defective in cutting, the control unit 42 executes the first program corresponding to the part. Execute the second program to do the following. Further, when the parts to be cut out from the workpiece W have the same shape, the control unit 42 repeatedly executes the first program, executes the second program when the cutting is defective, and then repeatedly executes the first program again. do. When the detection unit 41 detects a cutting defect during execution of the first program, the control unit 42 stops the execution of the first program and executes the second program, so that the control unit 42 stops the execution of the first program and executes the second program. The impact can be suppressed.

The acquisition unit 43 acquires a machining program and stores the acquired machining program in the storage unit 44 . Specifically, the acquisition unit 43 acquires a machining program from a device equipped with a CAM or the like via the communication unit 45 at an arbitrary timing before the process of cutting out parts from the workpiece W is executed. Regarding acquisition of the machining program, the acquisition unit 43 acquires the machining program from an external storage device storing the machining program via the communication unit 45 at an arbitrary timing before the process of cutting out parts from the workpiece W is executed. A machining program may also be obtained. The control unit 42 acquires the first program and the second program from the storage unit 44 and executes them. Note that the communication (network) by the communication unit 45 may be either wired or wireless.

FIG. 5 is a flowchart illustrating an example of the laser processing method according to the embodiment. In the following description of the flowchart, the contents shown in FIGS. 6 to 13 will be referred to as appropriate. 6 to 13 are diagrams illustrating an example of the flow of laser processing according to the embodiment. In FIGS. 6 to 13, parts to be cut out from the work W are parts Pa, Pb, and Pc, and predetermined routes corresponding to the respective parts are predetermined routes Ra, Rb, and Rc. In FIGS. 6 to 12, the cutting lines of the parts are shown by broken lines, and the cutting lines indicated by the predetermined routes are shown by dashed lines. In addition, in FIGS. 6 to 12, the direction of cutting is shown by a solid line arrow, and the state of the cutting process is shown by a solid line. Note that the machining program is acquired by the acquisition unit 43 at an arbitrary timing and stored in the storage unit 44.

The control unit 42 moves the laser head 10 while irradiating the processing laser (laser light L1) for cutting out parts (step S101). That is, the control unit 42 executes the first program. Specifically, the control unit 42 acquires a machining program corresponding to the workpiece W from the storage unit 44. Then, the control unit 42 executes the first program corresponding to the part Pa (see FIG. 6) among the acquired machining programs. As a result, as shown in FIG. 6, the laser head 10 moves to a position Sa where it starts cutting out the part Pa, and moves while irradiating the laser beam L1 along the cutting line of the part Pa. When cutting out the part Pa, the control unit 42 first irradiates the laser beam L1 to a location away from the cutting line of the part Pa to form a through hole HPa, and directs the laser beam L1 from the through hole HPa to the part Pa. Move it to the cutting line. Next, the control unit 42 moves the laser beam L1 along the cutting line of the part Pa. With the start of cutting out the part Pa, the imaging unit 30 images the part Pa irradiated with the processing laser (laser light L1) (step S102). Specifically, the imaging unit 30 images the cut portion of the part Pa under the control of the control unit 42 that executes a first program for cutting out the part Pa.

The detection unit 41 starts detecting defective cutting (step S103). Specifically, the detection unit 41 detects a cutting defect based on a captured image obtained by imaging by the imaging unit 30. Here, the explanation will be given assuming that the cutting process for the part Pa has been completed without any cutting defect being detected by the detection unit 41. The cutting line indicated by the predetermined path Ra corresponding to the part Pa is not cut. That is, if the detection unit 41 does not detect a cutting defect by the time the first program for cutting out the part Pa ends (step S103: NO), the control unit 42 determines whether there are any other parts to cut out. (Step S105). Specifically, after the execution of the first program for cutting out part Pa ends, the control unit 42 determines whether there is a first program for cutting out other parts. Here, the description will be made assuming that there is a first program that cuts out another part (for example, part Pb).

If the first program for cutting out other parts exists (step S105: YES), the control unit 42 executes the process in step S101. Specifically, the control unit 42 executes a first program corresponding to part Pb. As a result, as shown in FIG. 7, the laser head 10 moves to the position Sa where it starts cutting out the part Pb, and moves while irradiating the laser beam L1 along the cutting line of the part Pb. When cutting out the part Pb, the control unit 42 first irradiates the laser beam L1 to a location away from the cutting line of the part Pb to form a through hole HPb, and directs the laser beam L1 from the through hole HPb to the part Pb. Move it to the cutting line. Next, the control unit 42 moves the laser beam L1 along the cutting line of the part Pb. With the start of cutting out the part Pb, the imaging unit 30 images the cut portion of the part Pb irradiated with the laser beam L1 (step S102). The detection unit 41 starts detecting defective cutting (step S103).

Here, regarding the part Pb, it will be explained that the detection unit 41 has detected a cutting defect. For example, as shown in FIG. 8, the detection unit 41 detects a cutting defect at the timing when the laser head 10 moves to the position SP. In FIG. 8, a thick line indicates a state in which a cutting defect actually occurs. Note that the length of the thick line represents the elapsed time from the occurrence of a cutting defect until the detection unit 41 detects the cutting defect, but it is only emphasized and illustrated long for the purpose of explanation. It is not intended that it takes time to detect defects. If the detection unit 41 detects a cutting defect in a situation where the execution of the first program for cutting out the part Pb has not finished (step S103: YES), the control unit 42 stops cutting out the defective part Pb. Then, the laser head 10 is moved while irradiating the laser beam L1 along the predetermined path Rb (step S104). That is, the control unit 42 stops executing the first program corresponding to part Pb, and executes the second program corresponding to part Pb.

As a result, as shown in FIG. 9, the laser head 10 moves to a position Sb to start cutting out the part Pb corresponding to the predetermined path Rb, and emits the laser beam L1 along the cutting line indicated by the predetermined path Rb. Move while irradiating. The control unit 42 first irradiates the laser beam L1 at the position Sb to form a through hole HRb, and moves the laser beam L1 from the through hole HRb along a predetermined path Rb. Then, as shown in FIG. 10, the laser processing machine 100 cuts out a region surrounding the part Pb from the workpiece W by completing the cutting corresponding to the predetermined path Rb. The portion cut out along the predetermined path Rb is handled as, for example, a defective part Pb1. The defective part Pb1 includes a portion that was scheduled to be cut out as the part Pb. Note that in FIGS. 6 to 12, the through hole HRa is shown to be formed when the laser beam L1 is moved along the predetermined path Ra, and the through hole HRc is formed when the laser beam L1 is moved along the predetermined path Rc. It shows that it is formed when moving along.

Subsequently, the control unit 42 determines whether there are any other parts to be cut out (step S105). Specifically, after the second program for cutting out parts along the cutting line indicated by the predetermined route Rb has been executed, the control unit 42 determines whether there is a first program for cutting out other parts. Here, the description will be made assuming that there is a first program that cuts out another part (for example, part Pc).

If the first program for cutting out other parts exists (step S105: YES), the control unit 42 executes the process in step S101. Specifically, the control unit 42 executes the first program corresponding to the part Pc. As a result, as shown in FIG. 11, the laser head 10 moves to the position Sa where it starts cutting out the part Pc, and moves while irradiating the laser beam L1 along the cutting line of the part Pc. When cutting out the part Pc, the control unit 42 first irradiates a portion of the part Pc outward from the cutting line with a laser beam L1 to form a through hole HPc, and directs the laser beam L1 from the through hole HPc to the part Pc. Move it to the cutting line. Next, the control unit 42 moves the laser beam L1 along the cutting line of the part Pc. With the start of cutting out the part Pc, the imaging unit 30 images the cut portion of the part Pc irradiated with the laser beam L1 (step S102). Specifically, the imaging unit 30 images the cut portion of the part Pc under the control of the control unit 42 that executes a first program for cutting out the part Pc.

The detection unit 41 starts detecting defective cutting (step S103). Here, the explanation will be given assuming that the cutting process for the part Pc has been completed without any cutting defect being detected by the detection unit 41. That is, if the detection unit 41 does not detect a cutting defect by the time the first program for cutting out the part Pc ends (step S103: NO), the control unit 42 determines whether there are any other parts to cut out. (Step S105). Here, the description will be made assuming that there is no first program for cutting out other parts. That is, as shown in FIG. 12, the laser processing machine 100 completes the cutting corresponding to the part Pc. The cutting line indicated by the predetermined path Rc corresponding to the part Pc is not cut.

If the first program for cutting out other parts does not exist (step S105: NO), the control unit 42 selects parts Pa, Pb, Pc, and defective parts Pb1 (hereinafter referred to as parts Pa, etc.) for the loader device 80. (Step S106). Specifically, as shown in FIG. 13, the control unit 42 controls the loader drive unit 83 in order to pick parts Pa and the like for the workpiece W for which execution of the machining program has been completed. The loader device 80 has a loader head 81 including a suction pad 82, and a loader drive unit 83 allows the loader head 81 to be moved in the X direction, the Y direction, and the Z direction. The suction pad 82 is provided on the loader head 81 and is capable of suctioning parts Pa and the like by, for example, vacuum or reduced pressure.

The loader head 81 is moved above the workpiece W by the loader drive section 83. Then, the loader head 81 descends and holds the parts Pa and the like formed on the workpiece W by suctioning them with the suction pads 82 . Subsequently, the loader head 81 rises while adsorbing the parts Pa and the like, and moves to above the product pallet 90. Thereafter, the loader head 81 descends to release the parts Pa and the like, thereby placing the parts Pa and the like at a desired position. As a result, as shown in FIG. 13, the product pallet 90 includes parts Pa, Pb, and Pc, as well as defective parts Pa1, Pb1, and Pc1 (defective part Pa1 is cut along the cutting line indicated by predetermined path Ra). The defective part Pc1 is a part that has been cut along the cutting line indicated by the predetermined path Rc). Further, in the laser processing machine 100, for example, a conveyance device different from the loader device 80 conveys the remaining material (skeleton) excluding the parts Pa etc. after (or before) the loader device 80 suctions the parts Pa etc. A residual material conveying device may be provided. By placing a plurality of types of defective parts Pa1, Pb1, and Pc1 in one place, post-processing (for example, disposal, etc.) of the defective parts Pa1 and the like becomes easy. However, the present invention is not limited to placing the plurality of types of defective parts Pa1, Pb1, and Pc1 in one place, and each defective part Pa1, Pb1, and Pc1 may be placed in a different position.

In the embodiments described above, processing device 40 includes, for example, a computer system. The processing device 40 reads a control program stored in the storage unit 44 and executes various processes according to this control program. This control program, for example, causes a computer to cause a laser head to irradiate a processing laser onto a workpiece, to take an image of the cut part of the workpiece that has been irradiated with the processing laser, and to create an image obtained by the imaging. detecting a cutting defect based on the cutting defect; and moving a laser head while irradiating a processing laser along a predetermined path on the workpiece surrounding the cutting line of the defective part. This control program may be provided recorded on a computer-readable storage medium. Further, the processing device 40 does not need to be included in the laser processing machine 100. In such a case, the processing device 40 communicates with the laser processing machine 100 via the communication unit 45 and executes various controls on the laser processing machine 100.

Although the embodiments of the present invention have been described above, the technical scope of the present invention is not limited to the embodiments described above. It will be apparent to those skilled in the art that various changes or improvements can be made to the embodiments described above. Furthermore, forms with such changes or improvements are also included within the technical scope of the present invention. One or more of the requirements described in the embodiments and the like described above may be omitted. Furthermore, the requirements described in the embodiments and the like described above can be combined as appropriate. Moreover, the execution order of each process shown in this embodiment can be implemented in any order as long as the output of the previous process is not used in the subsequent process. Further, even if the operations in the embodiments described above are described using "first," "next," "successively," etc. for convenience, it is not essential that they be performed in this order. In addition, to the extent permitted by law, the disclosures of all documents cited in the above-mentioned embodiments, etc. are incorporated into the description of the main text.

1... Laser processing system 10... Laser head 30... Imaging section 40... Processing device 41... Detecting section 42... Control section 80... Loader device P, Pa, Pb, Pc ... Part Pb1 ... Defective parts Ra, Rb, Rc ... Predetermined route W ... Work

Claims (12)

A laser processing system that includes a laser processing machine that laser-processes a plate-shaped workpiece to cut out parts,
a laser head that irradiates the workpiece with a processing laser;
an imaging unit that images the cut portion of the workpiece irradiated with the processing laser;
a detection unit that detects a cutting defect based on an image acquired by the imaging unit;
a control unit that moves the laser head while irradiating the processing laser along a predetermined path on the workpiece surrounding a cutting line of the part that has failed to be cut;
A laser processing system equipped with The laser according to claim 1, wherein the detection unit detects a cutting defect based on one or both of a kerf width on the workpiece in the image and information regarding light reflected from the surface of the workpiece in the image. processing system. The laser processing system according to claim 1 or 2, wherein the predetermined path is rectangular in plan view. Each of the four sides of the rectangular predetermined path is set so that, in plan view, a portion of the cutting line of the defective part overlaps or a portion of the cutting line is nearby. , The laser processing system according to claim 3. 5. The laser processing system according to claim 3, wherein one side of the rectangular predetermined path is parallel to an outer edge of the workpiece. The laser processing system according to any one of claims 1 to 5, wherein the predetermined path is set so as not to overlap the cutting line of the adjacent parts in the workpiece. When the detection unit detects a cutting defect, the control unit stops cutting out the defective part and moves the laser head while irradiating the processing laser along the predetermined path. A laser processing system according to any one of claims 1 to 6. A first program for actual processing to cut out the part and a second program for moving the laser head while irradiating the processing laser along the predetermined path are created in advance,
The control unit according to claim 7, wherein when the detection unit detects a cutting failure during execution of the first program, the control unit stops execution of the first program and executes the second program. Laser processing system. The control unit moves the laser head while irradiating the processing laser along the predetermined path at a speed slower than cutting out the part. laser processing system. The laser processing system according to any one of claims 1 to 9, wherein a cutting line indicated by the predetermined path has a portion overlapping a cutting line of the part. The laser processing system according to any one of claims 1 to 10, further comprising a loader device that picks the cut out parts and the defective parts cut out along the cutting line indicated by the predetermined path. A laser processing method in a laser processing system having a laser processing machine that laser-processes a plate-shaped workpiece to cut out parts,
causing a laser head to irradiate the workpiece with a processing laser;
imaging a cut portion of the workpiece irradiated with the processing laser;
Detecting a cutting defect based on an image obtained by imaging;
moving the laser head while irradiating the processing laser along a predetermined path on the workpiece surrounding the cutting line of the part that has failed to be cut;
including laser processing methods.

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