Cutting method, cutting device, and product manufacturing method

Abstract

To improve the accuracy of cutting of a material to be cut.SOLUTION: A cutting method for cutting a thick plate 1 at a planned cutting position includes: a thick plate 1 position information acquisition step for acquiring outer shape position data of the thick plate 1; a cutting position information acquisition step 40B for acquiring cutting position data of the thick plate 1 according to a cutting device; and a position correction step 40C for correcting a relative position of the thick plate 1 and the cutting device, based on the outer shape position data and the cutting position data.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a technique for cutting a material to be cut, such as a metal plate, into specified dimensions, and a method for manufacturing a product using such a technique.

Background Art

[0002] For example, in the thick plate refining process at a steel mill, an operation of cutting a thick plate (an example of a material to be cut) rolled in a rolling process into specified dimensions is carried out. In this cutting operation, for example, after pressing the thick plate loaded on the conveying roll against the side guide and horizontally discharging it, while conveying the thick plate with the conveying roll, the crop portion of the thick plate is roughly cut with a crop shear, and the thick plate is width-cut with a side shear. Further, by cutting the thick plate in the longitudinal direction with an end shear, the thick plate is cut into a desired dimension.

[0003] At this time, when conveying the thick plate with the conveying roll, due to factors such as the roll peripheral speed difference caused by the wear of the conveying roll, the alignment deviation of the roll, and the distortion of the thick plate, the thick plate may skew with respect to the conveying direction (the direction serving as a reference for the cutting direction). When skewing occurs in the thick plate, the relative position of the thick plate with respect to the planned cutting position by the cutting device may shift, and in some cases, the thick plate cannot be accurately cut.

[0004] Therefore, before width-cutting the thick plate with the side shear (on the inlet side of the cutting device), the conveyance of the thick plate is temporarily stopped, and an operator visually checks whether it can be cut into a rectangle of a desired dimension. Then, horizontal discharging and cutting positioning of the skewed thick plate are carried out. However, there is a problem that determination errors in the cutting position due to human error for visual confirmation and variations due to differences in skill level occur.

[0005] On the other hand, for example, Patent Document 1 discloses a cutting method in which a reference mark assigned corresponding to the cutting position of a steel plate (a material to be cut) is detected by a detector, and based on the position of the detected reference mark, the width direction position of the material to be cut is adjusted, thereby cutting the material to be cut at a predetermined position.

Prior Art Documents

Patent Document

[0006]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0007] However, in the method of Patent Document 1, it is necessary to provide a reference mark corresponding to the cutting position with respect to the entire length of the material to be cut, which is time-consuming. In addition, the method described in Patent Document 1 continuously adjusts the position in the width direction of the material to be cut, and there is a risk that the accuracy of adjustment for the skew of the plate is poor.

[0008] The present invention has been made paying attention to the above points, and aims to improve the cutting accuracy by enabling more accurate adjustment of the relative position of the material to be cut.

Means for Solving the Problems

[0009] To solve the problems, one aspect of the present invention is a cutting method for cutting a material to be cut by a cutting device, including a step of acquiring material position information for acquiring outer shape position data which is position information of the outer shape of the material to be cut, a step of acquiring cutting position information for acquiring cutting position data which is information of a planned cutting position of the material to be cut by the cutting device, and a position correction step of correcting the relative position of the material to be cut with respect to the planned cutting position based on the acquired outer shape position data and cutting position data.

Effects of the Invention

[0010] According to the aspect of the present invention, even if there is a deviation in the relative position of the material to be cut with respect to the planned cutting position from the outer shape position data and the cutting position data of the material to be cut, it is possible to correct the deviation of the position. In particular, by using the outer shape position data and the cutting position data of the material to be cut, even if the material to be cut is inclined with respect to the planned cutting position, the inclination can be detected. As a result, the cutting of the material to be cut can be performed with higher accuracy.

Brief Description of the Drawings

[0011]

Figure 1

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Embodiments for Carrying Out the Invention

[0012] Next, embodiments of the present invention will be described with reference to the drawings. This embodiment relates to a method for manufacturing a product having a step of cutting a material to be cut into a target dimension by cutting. In the cutting process of this embodiment, a process of cutting the material to be cut into a target dimension is performed using a cutting device.

[0013] In the following description, as an example of the material to be cut, a thick plate made of a metal such as steel, aluminum, or titanium will be described. However, the material to be cut in the cutting method and cutting device of the present disclosure is not limited to metal materials.

[0014] (Cutting line) The cutting process of this embodiment is performed on a cutting line. In this embodiment, as shown in FIG. 1, the thick plate 1 is conveyed to the cutting line by a mounting device 2 composed of a chain conveyor, a walking beam, etc., and the thick plate 1 is placed on the conveying roll (conveying device) of the cutting line. Thereafter, in the cutting line of this embodiment, the thick plate 1 is sequentially cut into a desired dimension while being conveyed by the conveying roll which is a conveying device.

[0015] Specifically, when the thick plate 1 is placed on the conveying roll 3, it is pressed against the side guide 4, so that the horizontal feeding is performed and the front-rear direction of the thick plate 1 becomes the conveying direction. The horizontally fed thick plate 1 is conveyed by the conveying roll 3 to each cutting device arranged along the conveying direction. In this example, the cutting devices include a crop shear 5, a pair of side shears 6, and an end shear 9 along the conveying direction, and the thick plate 1 as the material to be cut is cut in this order and processed into a predetermined outer shape.

[0016] Specifically, first, by the crop shear 5, the front and rear crop portions of the thick plate 1 are roughly cut. The crop portions are formed at the tip and tail ends of the thick plate 1 by rolling. Then, the front and rear crop portions of the thick plate 1 are roughly cut along a direction perpendicular to the conveying direction by the crop shear 5. The thick plate 1 that has been roughly cut in the crop section is conveyed to the side shears 6, and both end portions in the width direction of the thick plate 1 are cut to a desired width dimension by a pair of side shears 6. Subsequently, the thick plate 1 that has been width-cut is conveyed to the end shears 9, and the longitudinal direction (conveying direction) of the thick plate 1 is cut to a desired dimension by the end shears 9.

[0017] By each cutting along the above cutting lines, in a top view, the thick plate 1 of a desired dimension is cut out, and a product made of the thick plate 1 is manufactured. Note that the cut-out thick plate 1 is appropriately subjected to the processes necessary for the product. Further, if necessary, a cutting process for further dividing the cut-out thick plate 1 may be executed.

[0018] (Cutting method) In the present embodiment, as an example, the case where the cutting process technology of the present disclosure is applied to a pair of side shears 6 among the above cutting devices is illustrated. However, the present disclosure can also be applied to cutting devices at other positions and cutting devices with other configurations.

[0019] The cutting method 40 of the present embodiment includes, as shown in FIG. 2, a work-piece position information acquisition step 40A, a cutting position information acquisition step 40B, and a position correction step 40C.

[0020] <Work-piece position information acquisition step 40A> The work-piece position information acquisition step 40A acquires outer shape position data which is the position information of the outer shape of the thick plate 1 in a top view. The outer shape position data may be composed of all data along the outer shape, but for example, it is preferably composed of the position information of feature points that define (specify) the outer shape of the thick plate 1. In the present embodiment, considering cutting the substantially rectangular thick plate 1 into a rectangular shape, the coordinates of the four corner portions (vertices 30) of the rectangle are used as the outer shape position data (see FIG. 7). As long as they are the coordinates of the positions that specify the outer shape of the thick plate 1 before cutting or the outer shape of the thick plate 1 after cutting, the coordinate data of other positions may be used as the outer shape position data.

[0021] <Cutting position information acquisition step 40B> The cutting position information acquisition step 40B acquires cutting position data, which is information on the planned cutting position of the thick plate 1 by the cutting device. In the present embodiment, since the thick plate 1 is cut linearly while being conveyed, the planned cutting position of the thick plate 1 is a straight line in a top view. Therefore, coordinate data at two or three or more positions separated in the conveying direction among the planned cutting positions may be used as the cutting position data. Note that the planned cutting position may be arc-shaped or the like. Information on the feature points defining the planned cutting position may be used as the cutting position data.

[0022] <Position correction step 40C> The position correction step 40C corrects the relative position of the thick plate 1 with respect to the planned cutting position based on the outer shape position data and the cutting position data.

[0023] The position correction step 40C calculates, from the outer shape position data and the cutting position data, for example, a first deviation amount consisting of the inclination angle of the thick plate 1 with respect to the planned cutting position and a second deviation amount consisting of the deviation amount in the width direction orthogonal to the planned cutting position. Note that the width direction orthogonal to the planned cutting position corresponds to the direction in which the material to be cut approaches and separates from the planned cutting position.

[0024] Then, when the first deviation amount (inclination angle) is not within the allowable range, the position correction step 40C changes the position (inclination) of at least one of the cutting device and the material to be cut in a direction in which the first deviation amount becomes smaller. Also, when the second deviation amount (deviation amount in the width direction) is not within the allowable range, the position correction step 40C moves the position of at least one of the cutting device and the material to be cut in the width direction in a direction in which the second deviation amount becomes smaller. Thereby, the process of correcting the relative position between the planned cutting position and the thick plate 1 is completed.

[0025] Here, in the cutting method of the present embodiment, the thick plate 1 can be imaged in a state where laser light is irradiated along the position that becomes the planned cutting position on or above the surface of the thick plate 1. Then, an imaging image of the thick plate 1 and the laser beam taken together is obtained. That is, an imaging image of the thick plate 1 with a cutting planned position presented along the surface is acquired. Also, an imaging image of the thick plate 1 taken without irradiating the laser beam is obtained.

[0026] Thereafter, from the above imaging images, processes for obtaining the outer shape position data in the work position information acquisition step 40A and obtaining the cutting position data in the cutting position information acquisition step 40B are performed.

[0027] At this time, the cutting position information acquisition step 40B may obtain the above cutting position data from a comparison between an imaging image of the thick plate 1 as the work irradiated with the laser beam and a second imaging image of the thick plate 1 as the work taken without irradiating the laser beam.

[0028] The cutting position data may be obtained from the cutting position information of the cutting device instead of from the imaging image. However, when obtaining the outer shape position data and the cutting position data from an imaging image of the thick plate 1 as the work irradiated with the laser beam, since two data are obtained from the same reference (imaging image), the information deviation between the two data can be suppressed to be small.

[0029] <Cutting processing device> Next, an example of a cutting processing device that realizes the above cutting processing method will be described. The cutting processing device of the present embodiment includes a conveying roll 3 that conveys the thick plate 1 as the work, a cutting device that cuts the thick plate 1, and a cutting position adjustment device that is one of the features of the present disclosure. Note that the cutting device in this example is a pair of side shears 6.

[0030] <Cutting position adjustment device> The cutting position adjustment device is a device that performs adjustment processing on the relative position with respect to the planned cutting position of the thick plate 1 before cutting by the cutting device. Here, this embodiment is a configuration example in which the thick plate 1 is cut by the cutting device while being conveyed by the conveying rolls 3. Therefore, the cutting position adjustment device of this embodiment is provided at the inlet position of a pair of side shears 6 which are the cutting devices.

[0031] Here, the interval in the width direction of the pair of side shears 6 is changed according to the plate width of the target product. For example, the pair of side shears 6 can be displaced in synchronization in the width direction by a drive actuator (not shown). This displacement amount can be obtained, for example, as the displacement amount with respect to the reference position.

[0032] As shown in FIG. 3, the cutting position adjustment device of this embodiment includes a planned cutting position presentation device 10, a position adjustment device 11, an imaging device 12, and a control device 13.

[0033] Here, the processing of the cutting position adjustment device is executed, for example, at the inlet position of the cutting device (a pair of side shears) by temporarily stopping the conveyed thick plate 1. It is also possible to execute the processing of the cutting position adjustment device while conveying the thick plate 1, and when it is determined that position correction is necessary, stop the conveyance of the thick plate 1 and perform position correction.

[0034] <Planned cutting position presentation device 10> The planned cutting position presentation device 10 presents the planned cutting position by the cutting device with respect to the surface of the thick plate 1 or above the surface. It is preferable to directly present the planned cutting position on the surface of the thick plate 1. However, marking the surface of the thick plate 1 to present the planned cutting position is not included. This is because once marked, the marking position on the thick plate will not change. That is, the planned cutting position presentation device 10 is configured to be able to present the planned cutting position by the cutting device regardless of the change in the position of the thick plate.

[0035] In this embodiment, it is an example of presenting the planned cutting position on the surface of the thick plate 1. The cutting planned position presentation device 10 of this embodiment consists of a laser light irradiation device 10. The laser light irradiation device 10 irradiates laser light at a position that will be the cutting planned position along the conveyance direction of the thick plate 1 on or above the surface of the thick plate 1.

[0036] The laser light irradiation device 10 of this embodiment is a device that irradiates a laser sheet PL which is a sheet-shaped laser light. By using sheet-shaped laser light, it becomes possible to directly present the cutting planned position on the surface of the thick plate 1. A pair of laser light irradiation devices 10 are provided corresponding to a pair of side shears. The pair of laser light irradiation devices 10 are each capable of moving in a direction orthogonal to the conveyance direction (the width direction of the thick plate 1) in conjunction with the pair of side shears 6. Thereby, the laser sheet PL is irradiated at the cutting planned position of the width cutting by the side shears 6 on the surface of the thick plate 1 (see FIG. 4). In this embodiment, the cutting planned position is presented as a line-shaped light extending in the conveyance direction.

[0037] As described above, the laser light irradiation device 10 can be displaced in the width direction of the thick plate 1 in conjunction with each of the pair of side shears 6 by acquiring the amount of displacement of each side shear with respect to the reference position. Also, by fixing each laser light irradiation device 10 to the housing portion of the corresponding side shear 6, it may be possible to correspond to the displacement of the side shear 6. Note that since the laser sheet PL may be irradiated above the thick plate 1, it can be arranged so as not to interfere with the conveyance roll 3 or the thick plate 1 being conveyed.

[0038] In FIGS. 1 and 4, the case of irradiating laser light from the downstream side to the upstream side in the conveyance direction is illustrated, but the laser light may be irradiated targeting the position of the blade portion 6a of the side shear 6 from the upstream side. In FIG. 1, for easy viewing of the laser light irradiation device 10, the laser sheet PL is shown shifted from the position of the thick plate 1. Actually, as shown in FIG. 4, in plan view, the laser sheet PL overlaps the thick plate 1.

[0039] Further, the laser beam may be a beam-shaped light extending along the conveyance direction above the thick plate 1. However, by making it sheet-shaped, the cutting planned position is presented directly on the surface of the thick plate 1, and even if the imaging axis of the imaging device is inclined from the vertical direction, the cutting planned position can be detected more accurately.

[0040] As the configuration for presenting the cutting planned position in the cutting planned position presenting device 10, a configuration other than the laser beam irradiating device 10 may be adopted. However, the sheet-shaped laser beam is simple and can present the cutting planned position with high accuracy. As other presentations of the cutting planned position, for example, a configuration in which a wire or the like is arranged with tension above the cutting planned position can be exemplified.

[0041] The irradiation of the laser beam is executed, for example, when the thick plate 1 exists on the inlet side of the cutting device. Further, the irradiation of the laser beam may be configured to be executed only at the time of imaging in synchronization with the imaging by the imaging device 12.

[0042] <Position adjusting device 11> The position adjusting device 11 is a driving device that changes the relative position of the thick plate 1. In this embodiment, since the thick plate 1 is cut in the conveyance direction by the cutting device, a configuration is exemplified in which the relative position of the thick plate 1 is changed by changing the position on the thick plate 1 side in consideration of the cutting accuracy. If the configuration is such that the cutting device side is moved instead of the thick plate 1 side for cutting, the relative position of the thick plate 1 may be changed by changing the position on the cutting device side, that is, changing the cutting planned position.

[0043] The position adjusting device 11 of this embodiment is composed of a magnet jack. The magnet jack 11 has a magnetic attachment portion 11a having an electromagnet as a main body, and is configured to be movable in the height direction and the width direction (the direction orthogonal to the conveyance direction) in accordance with a command from the control device 13. In the magnet jack of this embodiment, a pair of magnetic attachment portions 11a are arranged at intervals in the conveyance direction, and each magnetic attachment portion 11a is installed between the rollers 3a of the conveyance roll 3.

[0044] The magnetic jack 11 has a pair of magnetic attachment parts 11a magnetically attached to the lower surface of the thick plate 1. By raising the pair of magnetic attachment parts 11a, after floating the thick plate 1 from the roller 3a of the conveying roll 3, the position of the thick plate 1 can be adjusted by moving the pair of magnetic attachment parts 11a in the width direction of the thick plate 1. Further, the magnetic jack 11 can also adjust the inclination of the thick plate 1 with respect to the conveying direction by changing the moving amount of the pair of magnetic attachment parts 11a in the width direction. Then, when the position adjustment is completed, the pair of magnetic attachment parts 11a is lowered and the magnetic force is eliminated, so that the pair of magnetic attachment parts 11a is separated from the lower surface of the thick plate 1.

[0045] Here, the position adjustment device 11 is not limited to the magnetic jack. The position adjustment device 11 is not particularly limited as long as it is a driving device capable of changing the position of the thick plate 1 as the material to be cut.

[0046] <Imaging device 12> The imaging device 12 is composed of a camera installed above the position of the irradiated laser light and facing downward with the imaging unit. As a method of installing this imaging device 12, for example, a gantry-shaped stand (not shown) is provided so as to straddle the conveying roll 3, and the imaging device 12 is installed on the stand. In this way, by installing the imaging device 12 on the gantry-shaped stand, the thick plate 1 can be imaged from directly above. In addition, a stand may be provided on the machine side of the conveying roll 3, and the imaging device 12 may be installed on the stand so that the thick plate 1 is imaged from an obliquely upper direction by the imaging device 12. When imaging obliquely, it is preferable to perform image conversion processing on the image from directly above.

[0047] As the imaging device 12, one or a plurality of cameras are installed in a range capable of imaging the entire length and width of the target thick plate 1. When the imaging device 12 is composed of a plurality of cameras, it is preferable to synthesize the images captured by the respective cameras into one image in which the thick plate 1 and its surroundings are imaged.

[0048] The imaging device 12 images the outer shape of the target thick plate 1 according to a command from the control device 13. In this embodiment, the imaging device 12 images the outer shape of the thick plate 1 together with the laser sheet PL irradiated on the planned cutting position.

[0049] <Control device 13> The control device 13 is an arithmetic unit that performs control related to cutting position adjustment. As shown in FIG. 3, the control device 13 of this embodiment includes an image analysis unit 13A and a position correction unit 13B.

[0050] <Image analysis unit 13A> The image analysis unit 13A acquires a captured image captured by the imaging device 12, which captures both the thick plate 1 and the laser sheet PL irradiated on the thick plate 1. In addition, the image analysis unit 13A acquires a captured image of the thick plate 1 without irradiating the laser sheet PL.

[0051] Here, the captured image is a two-dimensional image of the thick plate 1 viewed from above. Also, the laser sheet PL irradiated on the planned cutting position preferably has a wavelength different from the wavelength of the illumination for imaging by the imaging device 12. For the laser sheet PL, for example, green laser light with a wavelength of 500 to 572 nm or red laser light with a wavelength of 600 to 780 nm is preferably used.

[0052] Then, the image analysis unit 13A analyzes the acquired captured image to calculate the outer shape position data (outer shape position data) of the thick plate 1 and the data of the planned cutting position (cutting position data). The image analysis unit 13A of this embodiment includes a cutting position extraction unit 13Aa and an outer shape extraction unit 13Ab.

[0053] [Cutting position extraction unit 13Aa] The cutting position extraction unit 13Aa performs a process of extracting the data of the planned cutting position (cutting position data) from the acquired captured image. First, as shown in Fig. 5(a), the cutting position extraction unit 13Aa emphasizes the laser irradiation position (laser sheet PL) on the captured image 20 by extracting the color corresponding to the wavelength of the irradiated laser sheet PL from the captured image 20 that has been captured.

[0054] At this time, as shown in Fig. 5(b), when extracting the color corresponding to the laser wavelength, portions where the color tone is close to the laser wavelength (portions with a strong reddish or greenish tint) may be extracted as the noise region 22. In this embodiment, the planned cutting position is a straight line. Therefore, as shown in Fig. 5(c), by extracting the straight line portion irradiated with the laser sheet PL from the image, the noise region 22 can be excluded and only the irradiated portion of the laser light can be extracted. As a method for extracting the straight line portion from the image, for example, there is a method using the Hough transform.

[0055] At this time, in order to easily extract the irradiation position of the laser sheet PL on the image, it may be configured to turn off the illumination during imaging by the imaging device 12 and perform imaging under conditions where the laser sheet PL is emphasized and appears clearly.

[0056] Also, the above-described captured image captured with the laser sheet PL irradiated and a second captured image captured with the laser sheet PL not irradiated are respectively acquired, and by taking the difference between the two captured images, a configuration may be adopted in which only the irradiated portion of the laser sheet PL is extracted.

[0057] [Outer shape extraction unit 13Ab] The outer shape extraction unit 13Ab acquires the outer shape position data of the thick plate 1 from the captured image 20 acquired by the imaging device 12.

[0058] The outer shape extraction unit 13Ab of this embodiment acquires a captured image that is the captured image captured by the imaging device 12 and shows the thick plate 1 in a state where the laser sheet PL is not irradiated. Then, image processing is performed on the captured image to extract the edge position of the outer shape of the thick plate 1 as the outer shape position data. Incidentally, the outer shape extraction unit 13Ab may extract the edge position of the outer shape of the thick plate 1 from the captured image of the thick plate 1 (see Fig. 5(a)) in a state where the laser sheet PL is irradiated, and extract it as outer shape position data. In this case, the line of the laser sheet PL may be removed from the captured image (see Fig. 5(a)) in advance, or the edge position of the thick plate may be specified based on the line of the laser sheet PL.

[0059] Fig. 6 is a schematic diagram of a two-dimensional image obtained by imaging the thick plate 1. In Fig. 6(a), reference numeral 1 indicates the area showing the thick plate 1, and reference numeral 22 indicates the noise area. The outer shape extraction unit 13Ab performs binarization processing on the captured image 20 (two-dimensional image) it has obtained to obtain a binarized image (see Fig. 6(b)). Next, the outer shape extraction unit 13Ab detects the areas on the binarized image by assigning the same number label to the areas where the pixels are continuous. Then, the area with the largest area among the detected areas is determined as the area of the thick plate 1. The data of the edge of the detected area of the thick plate 1 becomes the outer shape position data.

[0060] In this embodiment, the thick plate 1 to be cut has a substantially rectangular shape and is cut into a rectangular shape. Therefore, in this embodiment, by approximating the detected area of the thick plate 1 to a rectangle, the coordinates of the four vertices on the outer shape of the thick plate 1 are extracted as representative points (feature points) of the outer shape.

[0061] Here, the equipment (for example, the housing part of the conveying roll 3, etc.) that serves as the background when imaging the thick plate 1 may be configured to be painted with a different color from the thick plate 1. In this case, the noise area 22 on the image is reduced, and it becomes easier to detect only the area of the thick plate 1.

[0062] Alternatively, an image captured with the thick plate 1 placed on the conveying roll 3 and an image captured with the thick plate 1 not placed may be prepared respectively, and only the area of the thick plate 1 may be extracted by taking the difference between these images.

[0063] Furthermore, as a method for detecting the edge of the thick plate 1, it is also possible to use a method (such as Sobel filter, Laplacian filter, Canny filter, etc.) that detects the boundary by differentiating the luminance values of the pixels in the two-dimensional image. Here, in the processes described above, when using a plurality of images, the position of the imaging device and the basic imaging conditions shall be the same.

[0064] The image analysis unit 13A extracts the position of the laser beam from the image irradiated with the laser beam, and extracts the edge position of the outer shape of the thick plate 1 from the image not irradiated with the laser beam. Then, by synthesizing these two images, the relative position of the edge position of the thick plate 1 with respect to the position of the laser beam (planned cutting position) as shown in FIG. 7 is obtained. At this time, the image irradiated with the laser beam and the image not irradiated with the laser beam have the same conditions for the position of the imaging device and the basic imaging conditions. Therefore, when synthesizing the two images, the position of the laser beam and the edge position of the outer shape of the thick plate 1 can be easily and accurately positioned.

[0065] <Position correction unit 13B> Based on the analysis of the image analysis unit 13A, the position correction unit 13B obtains the relative position of the thick plate 1 with respect to the position of the laser beam (planned cutting position), and determines whether correction of the position of the thick plate 1 is necessary. If the position correction unit 13B determines that position correction is necessary, it corrects the position of the thick plate 1 via the position adjustment device 11 based on the obtained relative position.

[0066] The correction is performed, for example, so that the distances from the left and right edges of the thick plate 1 to the proximal planned cutting positions are within a predetermined range over the entire length. In the present embodiment, the amount of deviation of the relative position between the thick plate 1 and the planned cutting position is calculated from the outer shape position data and the cutting position data of the thick plate 1 calculated by the image analysis unit 13A, and the position of the thick plate 1 is corrected by controlling the magnet jack 11 based on the calculated amount of deviation.

[0067] Next, an example of the processing of the position correction unit 13B of the present embodiment will be described. The position correction unit 13B acquires the outer shape position data and the cutting position data of the thick plate 1 required by the image analysis unit 13A. Next, the position correction unit 13B calculates the deviation amount of the relative position of the position of the thick plate 1 with respect to the planned cutting position by comparing the outer shape position data and the cutting position data. Then, based on the calculated deviation amount, the relative position of the thick plate 1 and the cutting device is corrected.

[0068] Specifically, the position correction unit 13B of the present embodiment calculates the deviation amount of the relative position with respect to the planned cutting position of the thick plate 1 by comparing the cutting position data (the position data of the laser sheet PL) extracted by the cutting position extraction unit 13Aa and the outer shape position data of the thick plate 1 extracted by the outer shape extraction unit 13Ab. Then, based on the deviation amount, the position of the thick plate 1 is displaced by the magnet jack 11 to correct the position of the thick plate 1.

[0069] Here, the cutting position data (the position data of the laser sheet PL) may be expressed, for example, by the position coordinates of two points separated in the conveyance direction (the extending direction of the laser beam) among the position data of the laser sheet PL. Further, in the present embodiment, the outer shape position data of the thick plate 1 is expressed by the coordinate data of four vertices.

[0070] [Example of calculating deviation amount] An example of the method for calculating the deviation amount will be described with reference to FIG. 7.

[0071] First, as shown in FIG. 7(a), the position correction unit 13B obtains the direction 31 orthogonal to the irradiation direction of the laser sheet PL from the cutting position data. Also, among the coordinate data of the four vertices 30 that define the outer shape position data, the direction of the straight line connecting the two vertices on the tip end side or the two vertices on the tail end side of the thick plate 1 is obtained as the width direction 32 of the thick plate 1. Then, the angle θ formed by the direction 31 orthogonal to the irradiation direction and the width direction 32 of the thick plate 1 is obtained, and the angle θ is calculated as the inclination angle θ of the thick plate 1 with respect to the planned cutting position. Thereby, the inclination angle θ is obtained as the first deviation amount.

[0072] Then, the position correction unit 13B determines whether or not this inclination angle θ is within the threshold value. If it is determined that it is not within the threshold value, the following process is executed. That is, as shown in Fig. 7(b), the thick plate 1 is magnetically attracted and lifted by the magnet jack 11, and the pair of magnetic attachment portions 11a are moved to the opposite sides in the width direction. The amount of movement is executed according to the inclination angle θ. Thereby, the thick plate 1 is rotated by the inclination angle θ. Note that the threshold value of the inclination angle θ is preferably about ±5°, for example.

[0073] Here, by moving the pair of magnetic attachment portions 11a to the opposite sides in the width direction, while suppressing the displacement of the thick plate 1 itself in the width direction, the position of the thick plate 1 is corrected in the direction in which the inclination angle θ becomes smaller. Also, until the position correction is completed, the state of lifting the thick plate 1 by the magnet jack 11 is maintained.

[0074] Next, the position correction unit 13B calculates the center-of-gravity coordinates of the thick plate 1 from the four vertices of the thick plate 1. Then, the displacement amount in the width direction between the coordinate in the width direction of the center-of-gravity coordinate CG and the coordinate of the center position PL0 in the width direction of the pair of laser sheets PL is calculated as the second displacement amount. The second displacement amount is also described as the displacement amount d in the width direction of the thick plate 1.

[0075] Then, the position correction unit 13B determines whether or not this displacement amount d in the width direction is within the threshold value. If it is determined that it is not within the threshold value, the following process is performed.

[0076] As shown in Fig. 7(c), the pair of magnetic attachment portions 11a are moved in the same direction as the plate width direction so that the coordinate in the width direction of the center-of-gravity coordinate of the thick plate 1 coincides with the center coordinate in the width direction of the laser sheet PL. Note that the threshold value of the displacement amount d in the width direction is preferably about ±10 mm, for example.

[0077] Here, in the state of FIG. 7(a), the inclination angle θ formed by the direction 31 orthogonal to the irradiation direction and the width direction 32 of the thick plate 1, and the displacement amount d in the width direction between the coordinate in the width direction of the center of gravity coordinate of the thick plate 1 and the center coordinates in the width direction of the pair of laser sheets PL are obtained. For each magnetic attachment portion 11a, each magnetic attachment portion 11a may be moved by only the final movement amount obtained by adding up the movement amount in FIG. 7(b) and the movement amount in FIG. 7(c).

[0078] FIG. 8 is a schematic diagram in the case of performing only the correction of the second displacement amount. In this case, the position correction unit 13B moves the pair of magnetic attachment portions 11a only in the same direction in the width direction so that the coordinate in the width direction of the center of gravity coordinate CG of the thick plate 1 coincides with the coordinate of the center position PL0 in the width direction of the laser sheet PL.

[0079] After moving the position of the thick plate 1 as described above, the process returns to the processes of the image analysis unit 13A and the position correction unit 13B again, and the process is repeated until both the first displacement amount and the second displacement amount are within the threshold values.

[0080] Furthermore, the control device 13 of the present embodiment determines the number of vertex coordinates of the thick plate 1 located between the irradiation positions of the pair of laser sheets PL. Then, based on the determination, when the number of vertex coordinates of the thick plate 1 is zero, that is, when there is a cutting position inside the edge of the thick plate 1, the control device 13 determines that the cutting position is normal and ends the position correction. Then, the thick plate 1 is conveyed toward the side shear 6, and the side shear 6 executes cutting in the width direction of the thick plate 1.

[0081] On the other hand, when the control device 13 determines that the number of vertex coordinates of the thick plate 1 located between the irradiation positions of the pair of laser sheets PL is one or more, the control device 13 determines that the thick plate 1 is abnormal and displays an abnormality alert. When the abnormality alert is displayed, an operator visually checks the cause of the abnormality.

[0082] (Processing flow of the control device 13) An example of the control flow of the control device 13 will be described using the flow of FIG. 9. First, in step S10, the control device 13 sets the interval of the laser sheet PL (= the widthwise position of the side shear 6) according to the planned cutting position of the thick plate 1, and then proceeds to step S20 to irradiate the surface of the thick plate 1 with the laser sheet PL (see FIG. 4).

[0083] Next, in step S30, the imaging device 12 images the thick plate 1. Note that the captured images include both an image in a state where the laser light is irradiated and an image in a state where the laser light is not irradiated. Next, in steps S40 to S50, cutting position data of the planned cutting position and outer shape position data of the thick plate 1 are extracted from the captured images of the imaging device 12 by the processing of the image analysis unit 13A. The cutting position data is data of the irradiation position of the laser sheet PL. The outer shape position data is, in this embodiment, data of the edge positions of the entire circumference of the thick plate 1.

[0084] Next, in step S60, four vertex coordinates of the thick plate 1 are obtained from the outer shape position data of the thick plate 1 extracted by the image analysis unit 13A. Subsequently, in step S70, as the first deviation amount, the inclination angle θ of the thick plate 1 with respect to the planned cutting position is calculated. Then, in step S80, it is determined whether or not the inclination angle θ is within the threshold value. If it is within the threshold value (Yes), the process proceeds to step S100. On the other hand, if the inclination angle θ is not within the threshold value (No), the process proceeds to step S90.

[0085] In step S90, the thick plate 1 is lifted by the magnet jack 11 and rotated by the inclination angle θ. After the rotation of the thick plate 1, the process proceeds to step S30, and the thick plate 1 is imaged again, and the processes of steps S40 to S70 are executed until the inclination angle θ becomes within the threshold value.

[0086] Also, when the process proceeds to step S100, the widthwise deviation amount d between the center-of-gravity coordinates of the thick plate 1 and the center coordinates in the width direction of the pair of laser sheets PL is calculated, and it is determined whether or not the widthwise deviation amount d is within the threshold value. If it is within the threshold value (Yes), the process proceeds to step S120. On the other hand, if the widthwise deviation amount d is not within the threshold value (No), the process proceeds to step S110.

[0087] In step S110, the thick plate 1 is moved in the width direction by the width direction displacement amount d by the magnetic jack 11. After the movement of the thick plate 1, the process returns to step S30, the thick plate 1 is imaged again, and the steps S40 to S100 are repeated until the width direction displacement amount d is within the threshold value.

[0088] Also, when shifting to step S120, the number n of vertex coordinates of the thick plate 1 located between the irradiation positions (planned cutting positions) of the pair of laser sheets PL is determined. When it is determined that the number of vertex coordinates is zero (n = 0), the process proceeds to step S130. In step S130, it is determined that the cutting position is normal, the position correction process of the thick plate 1 is completed, and the process proceeds to step S140. In step S140, the thick plate 1 is conveyed toward the side shear 6, and cutting in the width direction of the thick plate 1 is executed.

[0089] On the other hand, in step S120, when it is determined that the number of vertex coordinates is 1 or more (n = 1 to 4), the process proceeds to step S150. In step S150, it is determined that the cutting position is abnormal, the process proceeds to step S160, an abnormality alert is notified, and the flow ends. Normally, the width of the thick plate 1 before cutting is wider than the interval between the left and right side shears 6. The processes of steps S120 to S160 are processes different from the process of correcting the relative position of the thick plate 1.

[0090] (Operation and others) According to the present embodiment, the thick plate 1 is imaged by the imaging device 12, the cutting position data and the outer shape position data of the thick plate 1 are extracted from the captured image, and these data are compared. As a result, the displacement amount of the thick plate 1 with respect to the planned cutting position can be calculated, and the relative position of the thick plate 1 can be corrected based on the displacement amount.

[0091] Particularly in the present embodiment, since the planned cutting position is irradiated on the surface of the thick plate 1 by the laser sheet PL, it is possible to compare the actual outer shape position data (edge) of the thick plate 1 with the cutting position data actually irradiated on the thick plate 1, and it is possible to accurately calculate the displacement amount of the thick plate 1. (Modification example)

[0092] In the above embodiment, when there is a deviation between the cutting position and the thick plate 1, the position of the thick plate 1 is adjusted with respect to the cutting device (side shear 6). However, a configuration in which the position of the cutting device (side shear 6) is adjusted may also be used.

[0093] Further, in the above embodiment, the cutting planned position is directly irradiated on the surface of the thick plate 1 by the laser sheet PL, but it is not limited thereto. A configuration may be adopted in which cutting information is acquired from a higher-level computer, and the outer shape position data and the cutting position data of the thick plate 1 are compared by displaying the cutting position data on the image of the thick plate 1 taken.

[0094] Further, in the above description, the case where the outer shape position data is acquired from the image of the thick plate 1 imaged by the imaging device 12 is exemplified, but it is not limited thereto. Information on the outer shape of the thick plate 1 may be acquired by an optical cutting method or other distance meters.

[0095] (Others) The present disclosure may also adopt the following configuration. (1) A cutting method for cutting a material to be cut by a cutting device, comprising: a material to be cut position information acquisition step of acquiring outer shape position data which is position information of the outer shape of the material to be cut; a cutting position information acquisition step of acquiring cutting position data which is information of a cutting planned position of the material to be cut by the cutting device; a position correction step of correcting the relative position of the material to be cut with respect to the cutting planned position based on the acquired outer shape position data and cutting position data; and a cutting method having the above steps. (2) A step of irradiating laser light along the cutting planned position on or above the surface of the material to be cut, and performing processing for acquiring the outer shape position data in the material to be cut position information acquisition step and acquiring the cutting position data in the cutting position information acquisition step from the captured image of the material to be cut. (3) The cutting position information acquisition step obtains the cutting position data by comparing an imaging image obtained by imaging the material to be cut with a laser beam irradiated thereon and a second imaging image obtained by imaging the material to be cut without irradiating the laser beam. (4) The material to be cut is conveyed by a conveying roller and cut by a cutting device along the conveying direction. At the inlet position of the cutting device, at least the acquisition process of the outer shape position data by the material to be cut position information acquisition step and the correction process of the relative position by the position correction step are executed. (5) The position correction step is as follows. As the relative position of the material to be cut with respect to the planned cutting position, a first deviation amount consisting of the inclination angle of the material to be cut with respect to the planned cutting position and a second deviation amount consisting of the deviation amount in the direction in which the material to be cut approaches or separates from the planned cutting position are calculated. Based on the first deviation amount and the second deviation amount, the relative position is corrected by changing the position of at least one of the cutting device and the material to be cut. (6) A cutting processing device for cutting a material to be cut with a cutting device, A planned cutting position presentation device capable of irradiating a laser beam along the planned cutting position on or above the surface of the material to be cut, An imaging device capable of imaging the material to be cut and the laser beam together, A position adjustment device for adjusting the position of the material to be cut, An image analysis unit that extracts the planned cutting position and the outer shape position of the material to be cut from the imaging image captured by the imaging device, Based on the planned cutting position and the outer shape position of the material to be cut extracted by the image analysis unit, when the relative position of the material to be cut with respect to the planned cutting position is obtained and it is determined that correction of the position of the material to be cut is necessary based on the obtained relative position, a position correction unit that corrects the position of the material to be cut via the position adjustment device. A cutting processing device having the above. (7) The material to be cut is cut by the cutting device while being conveyed by a conveying device, The imaging device is disposed on the inlet side of the cutting device. (8) A step of cutting a material to be cut by the cutting processing device of the present disclosure. Method for manufacturing a product

Example

[0096] A laser sheet simulating a planned cutting position was irradiated onto a steel plate simulating a thick plate, and in that state, the steel plate was imaged from above with a camera. Figure 10(a) shows the captured image. Figure 10(b) shows an image in which the laser irradiation position was extracted by the method described in the embodiment from the captured image.

[0097] Also, an image of the steel plate imaged from above with a camera without irradiating the above laser sheet is shown in Figure 11(a). Figure 11(b) shows an image in which the outer shape of the steel plate was extracted by the method described in the embodiment from that image.

[0098] And by superimposing the laser irradiation position on the two-dimensional image shown in Figure 10(b) and the edge position of the steel plate shown in Figure 11(b), it can be seen that the relationship between the laser irradiation position and the edge position of the steel plate can be detected.

Explanation of reference numerals

[0099] 1 Thick plate (material to be cut) 2 Mounting device 3 Conveyor roll (conveying device) 4 Side guide 5 Crop shear 6 Side shear (cutting device) 9 End shear 10 Device for presenting planned cutting position 11 Magnet jack (position adjusting device) 11a Magnetic attachment part 12 Imaging device 13 Control device 13A Image analysis section 13B Position correction section 40 Cutting method 40A Process for obtaining position information of material to be cut 40B Process for obtaining cutting position information 40C Position correction process d Amount of deviation in width direction θ Inclination angle

Claims

1. A cutting method for cutting a workpiece by a cutting device, comprising the steps of: a workpiece position information acquisition step of acquiring outer shape position data which is outer shape position information of the workpiece; a cutting position information acquisition step of acquiring cutting position data which is information on a planned cutting position of the workpiece by the cutting device; a position correction step of correcting a relative position of the workpiece with respect to the intended cutting position based on the acquired outer shape position data and cutting position data; The cutting method includes the steps of:

2. A step of irradiating a laser beam onto or above a surface of the workpiece along the intended cutting position, From the captured image of the workpiece, outer shape position data is acquired in the workpiece position information acquisition step, and cutting position data is acquired in the cutting position information acquisition step. The cutting method according to claim 1.

3. The cutting position information acquisition step acquires the cutting position data by comparing a captured image of the workpiece while irradiating the laser light with a second captured image of the workpiece while not irradiating the laser light. The cutting method according to claim 2.

4. The material to be cut is conveyed by a conveying roller and cut by a cutting device along the conveying direction. At least the outer shape position data is acquired by the workpiece position information acquisition step, and the relative position is corrected by the position correction step, at the inlet position of the cutting device. The cutting method according to claim 1.

5. The position correction step includes: As a relative position of the workpiece with respect to the planned cutting position, a first deviation amount consisting of an inclination angle of the workpiece with respect to the planned cutting position and a second deviation amount consisting of a deviation amount in a direction in which the workpiece approaches or moves away from the planned cutting position are calculated; correcting the relative positions by changing a position of at least one of the cutting device and the workpiece based on the first deviation amount and the second deviation amount; A cutting method according to any one of claims 1 to 4.

6. A cutting processing device that cuts a workpiece with a cutting device, A cutting position indicating device capable of irradiating a laser beam along a cutting position on or above a surface of the workpiece; an imaging device capable of imaging the workpiece and the laser light together; A position adjustment device for adjusting the position of the workpiece; An image analysis unit that extracts a cutting position and an outer shape position of a workpiece from the captured image captured by the imaging device; A position correction unit obtains a relative position of the workpiece relative to the planned cutting position from the planned cutting position and the outer shape position of the workpiece extracted by the image analysis unit, and corrects the position of the workpiece via the position adjustment device if it is determined that the position of the workpiece needs to be corrected based on the obtained relative position; A cutting processing device having the above structure.

7. The workpiece is cut by the cutting device while being conveyed by a conveying device, The imaging device is disposed on the inlet side of the cutting device.

7. A cutting apparatus according to claim 6.

8. The cutting apparatus according to claim 6 or 7 includes a step of cutting a workpiece. How the product is manufactured.

Images