Sheet processing apparatus, cutting blade wear determination apparatus, cutting blade wear determination method, and program

Abstract

A cutting-knife wear-out determination device (31) of a sheet processing apparatus is provided with a cutting control section (33), a cutting trace extraction section (34), and a determination section (35). The cutting control section (33) causes a lifting mechanism capable of moving a cutting knife in a direction intersecting a sheet placed on a table, and a parallel movement mechanism capable of moving the cutting knife in parallel with a surface of the table in a state of contact with the table, to operate, and instructs formation of a cutting surface by the cutting knife on the sheet placed on the table. The cutting trace extraction section (34) acquires an image obtained by a camera (21) photographing a back surface of the sheet of a portion on which formation of the cutting surface is instructed, and extracts a cutting trace that is a line at which the formed cutting surface intersects the back surface of the sheet from the image. The determination section (35) determines that the cutting knife on which formation of the cutting surface is instructed has worn out in a case where a line at which the cutting surface formed by the cutting knife intersects the back surface of the sheet, that is, an assumed line, and the cutting trace extracted by the cutting trace extraction section (34) are not coincident.

Description

Technical Field

[0001] The present invention relates to a sheet processing apparatus having a cutting blade capable of forming a cutting surface extending from the surface of a sheet to the back side. Background Technology

[0002] Sheets are cut and creasing, and the processed sheets are assembled for use as packaging boxes and display cases. Common methods for cutting sheets include using die-cutting and drawing machines. For example, as described in Patent Document 1, a so-called platform-type automatic cutter is known, which has a cutter mounted on a platform-type drawing machine. Such an automatic cutter is configured to drive a cutting blade according to set data to cut the sheet placed on the cutting table.

[0003] Cutting blades used for slitting sheet material gradually wear down due to repeated cutting. Therefore, the wear is estimated by the cumulative length of cuts, and the cutting blades are replaced accordingly. For example, in the blade replacement period management device of Patent Document 2, the conveying distance of the continuously conveyed strip-shaped roll W is detected and written into an IC tag. The controller compares the limit conveying distance stored in the IC tag with the actual cumulative conveying distance of the roll. If the actual cumulative conveying distance of the roll exceeds the limit conveying distance, the controller issues a stop command to the slitting machine or an alarm command to the operator.

[0004] In the cutting machine of Patent Document 3, the cutting of sheet material is performed in an operating position where an inclined cutting blade is inserted into the sheet material from above, becoming part of the blade edge. The control unit of the cutting machine monitors and stores cutting amounts such as cutting distance while managing the process. If the cutting amount at the operating position exceeds a limit set as the lifespan, control is activated to proceed to the next operating position.

[0005] Existing technical documents

[0006] Patent documents

[0007] Patent Document 1: Japanese Patent Application Publication No. 7-24785

[0008] Patent Document 2: Japanese Patent Application Publication No. 2008-238325

[0009] Patent Document 3: Japanese Patent Application Publication No. 2013-99811 Summary of the Invention

[0010] The problem that the invention aims to solve

[0011] The cutting blades of sheet processing equipment sometimes wear out before reaching their cumulative cutting distance limit. This wear and tear on the cutting blades goes unnoticed, resulting in defective sheets. Reducing the limit lowers the defect rate, but the cutting blades are wasted, increasing the frequency of blade replacements and decreasing operational efficiency.

[0012] Sometimes the cutting blade is damaged at the tip, sometimes the blade is chipped in the middle, and sometimes the blade becomes dull. It is difficult to judge the wear and tear of the blade based on only one pattern.

[0013] The present invention was made in view of the above circumstances, and its object is to reliably detect the wear of the cutting blade using a sheet processing apparatus.

[0014] Technical solutions for solving the problem

[0015] The sheet processing apparatus according to the first aspect of the present invention includes: a worktable for holding a sheet placed on its surface; a cutting blade capable of forming a cutting surface extending from one surface to the other on the sheet held on the worktable surface; a lifting mechanism capable of moving the cutting blade in a direction intersecting the worktable surface between a position where the cutting blade contacts the worktable and a position where it separates from the sheet placed on the worktable; a parallel movement mechanism capable of moving the cutting blade parallel to the worktable surface while in contact with the worktable; a conveying mechanism capable of placing the sheet on the worktable and separating it from the worktable, and capable of moving the sheet while separated from the worktable; and a cutting control unit that operates the parallel movement mechanism and the lifting mechanism, and instructs the cutting blade to move the sheet on the worktable surface. A cutting surface is formed on a sheet placed on a worktable; an imaging device, which, while the sheet after the cutting surface has been indicated is separated from the worktable by a conveying mechanism, images the back side of the sheet; a cutting mark extraction unit, which, while the sheet after the cutting surface has been indicated is separated from the worktable, acquires an image of the back side of the sheet where the cutting surface has been indicated by the imaging device, and extracts the cutting mark from the image as a line intersecting the formed cutting surface and the back side of the sheet; and a determination unit, which determines that the cutting tool indicating the formation of the cutting surface has been worn if the line, which is assumed to be formed by a cutting blade intersecting the cutting surface and the back side of the sheet, is inconsistent with the cutting mark extracted by the cutting mark extraction unit.

[0016] Preferably, the cutting control unit instructs the formation of a cutting surface in a blank area of ​​the sheet, which is different from the cutting surface used to form the workpiece cut from the sheet. The cutting mark extraction unit obtains an image of the back side of the sheet where the blank cutting surface is formed by the imaging device, and extracts the cutting marks formed on the blank cutting surface from the image. If the determination unit determines that the cutting blade for which the cutting surface was instructed has been worn when the line that is assumed to be formed on the blank cutting surface is inconsistent with the cutting marks formed on the blank cutting surface, the cutting blade for which the cutting surface was instructed has been worn.

[0017] Preferably, the device includes multiple cutting blades capable of independently forming a cutting surface extending from the surface to the back side on a sheet held on the surface of a worktable. The cutting control unit instructs each cutting blade to form a different cutting surface. The cutting trace extraction unit extracts the cutting trace of the cutting surface formed by the cutting blade from an image for each cutting blade. The determination unit determines that the cutting blade for which the cutting surface was instructed has been worn if the imagined line of the cutting surface formed by the cutting blade is inconsistent with the cutting trace of the formed cutting surface.

[0018] Preferably, the cutting control unit also includes multiple parallel movement mechanisms and multiple lifting mechanisms that enable the cutting blades to move independently of each other. If the determination unit determines that a certain cutting blade has been worn out, the cutting control unit replaces the cutting blade that has not been determined to be worn out with one of the multiple cutting blades from the sheet to be processed next to form a predetermined cut surface formed by the cutting blade that has been determined to be worn out.

[0019] The second aspect of the present invention relates to a cutting blade wear determination device comprising: a cutting control unit that operates a lifting mechanism and a parallel movement mechanism, and instructs the formation of a cutting surface on a sheet held by a worktable; the lifting mechanism enabling the cutting blade to move in a direction intersecting the surface of the worktable between a position where the cutting blade contacts the worktable and a position where it separates from the sheet placed on the worktable; the cutting blade enabling the formation of a cutting surface extending from the surface of the sheet placed on the worktable and held by the worktable to the back side; and the parallel movement mechanism enabling the cutting blade to move parallel to the surface of the worktable while in contact with it; and a cutting mark extraction unit that, when transported by a conveying mechanism... After the sheet with the cut surface indicated for formation is separated from the worktable, an image is obtained by the imaging device capturing the back side of the sheet at the portion where the cut surface was indicated for formation. A cutting mark, which is the line where the cut surface is indicated for formation intersects with the back side of the sheet, is extracted from the image. The conveying mechanism can separate the sheet placed on the worktable from the worktable and move the sheet while it is separated from the worktable. The determination unit determines that the cutting blade with the indicated cut surface for formation has been worn if the line, which is assumed to be formed by the cutting blade on the sheet and intersects with the back side of the sheet, is inconsistent with the cutting mark extracted by the cutting mark extraction unit.

[0020] The third aspect of this invention relates to a cutting blade wear determination method performed by a cutting blade wear determination device. The cutting blade wear determination method includes: a cutting control step, which operates a lifting mechanism and a parallel movement mechanism, and instructs the formation of a cutting surface on a sheet held by a worktable. The lifting mechanism enables the cutting blade to move in a direction intersecting the surface of the worktable between a position contacting the worktable and a position separating from the sheet placed on the worktable. The cutting blade forms a cutting surface extending from the surface of the sheet held by the worktable to its back side. The parallel movement mechanism enables the cutting blade to move parallel to the surface of the worktable while in contact with it. A cutting mark is also included. The trace extraction step involves acquiring an image of the back side of the sheet where the cut surface has been indicated, taken by an imaging device, while the sheet is separated from the worktable by a conveying mechanism. The image is then extracted from the image as a line intersecting the cut surface and the back side of the sheet. The conveying mechanism can place the sheet on and separate it from the worktable, and move the sheet while it is separated from the worktable. The determination step involves determining that if the line, which is assumed to be formed by a cutting blade and intersecting the cut surface and the back side of the sheet, does not match the cutting trace extracted in the trace extraction step, the cutting blade that indicated the formation of the cut surface has been worn.

[0021] The fourth aspect of the invention relates to a program that causes a computer to perform the following steps: a cutting control step, which operates a lifting mechanism and a parallel movement mechanism, and instructs the formation of a cutting surface on a sheet held by a worktable. The lifting mechanism enables the cutting blade to move in a direction intersecting the surface of the worktable between a position in contact with the worktable and a position separated from the sheet placed on the worktable. The cutting blade is capable of forming a cutting surface extending from the surface of the sheet placed on the worktable and held by the worktable to the back side. The parallel movement mechanism enables the cutting blade to move parallel to the surface of the worktable while in contact with it. A cutting mark extraction step, which involves transporting the indicated... After the cut surface has been formed, the sheet is separated from the worktable. An image is captured by an imaging device of the back side of the sheet where the cut surface has been formed. A cutting mark, which is the line where the cut surface intersects with the back side of the sheet, is extracted from the image. The conveying mechanism can place the sheet on the worktable and separate it from the worktable, and move the sheet while it is separated from the worktable. In the determination step, if the line that is assumed to be formed by the cutting blade on the sheet and intersects with the back side of the sheet (i.e., the assumed line) is inconsistent with the cutting mark extracted in the cutting mark extraction step, it is determined that the cutting blade that indicated the formation of the cut surface has been worn.

[0022] Invention Effects

[0023] According to the present invention, a cutting mark, which is the intersection line between the back side of the sheet and the cutting surface, is extracted from an image of the back side of the sheet with a cutting blade. If the line intersecting the indicated cutting surface and the back side of the sheet, i.e., the hypothetical line, is inconsistent with the extracted cutting mark, it is determined that the cutting blade has been worn. Therefore, the wear of the cutting blade can be reliably detected. Attached Figure Description

[0024] Figure 1 This is a perspective view of the sheet processing apparatus according to Embodiment 1 of the present invention.

[0025] Figure 2 This is a structural diagram of the cutting mechanism involved in Embodiment 1.

[0026] Figure 3 This is a block diagram illustrating a structural example of the cutting blade wear determination device according to Embodiment 1.

[0027] Figure 4 This is a diagram illustrating an example of sheet material processing.

[0028] Figure 5 This is a flowchart illustrating an example of the operation for determining the wear of the cutting blade according to Embodiment 1.

[0029] Figure 6This is a schematic perspective view of the sheet processing apparatus according to Embodiment 2 of the present invention.

[0030] Figure 7 This is a diagram showing an example of the cut surface involved in Embodiment 2.

[0031] Figure 8 This is a flowchart illustrating an example of the operation for determining the wear of the cutting blade according to Embodiment 2.

[0032] Figure 9 This is a block diagram illustrating an example of the hardware structure of the cutting blade wear determination device according to the embodiment. Detailed Implementation

[0033] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. Furthermore, the same or equivalent parts in the drawings are labeled with the same reference numerals.

[0034] Implementation method 1.

[0035] Figure 1 This is a perspective view of the sheet processing apparatus according to Embodiment 1 of the present invention. The sheet processing apparatus 1 consists of a processing table 2 and an infeed / outfeed 3. The processing table 2 forms a cutting surface on the sheet material placed on the worktable 9. The infeed / outfeed 3 places the sheet material on the worktable 9 and separates the processed sheet material from the worktable 9 for transport. In the following description, the direction in which the processing table 2 and the infeed / outfeed 3 are arranged is defined as the X-axis, and the direction parallel to the surface of the worktable 9 and orthogonal to the X-axis is defined as the Y-axis. Furthermore, the direction orthogonal to the X-axis and Y-axis, that is, the direction orthogonal to the surface of the worktable 9, is defined as the Z-axis. The X-axis direction is also referred to as front-back, the Y-axis direction as left-right, and the Z-axis direction as up-down.

[0036] In the sheet processing apparatus 1, the worktable 9, on which the sheet to be processed is placed, is kept parallel to the XY plane and moves back and forth on the processing frame 2 and the loading and unloading frame 3. Figure 1 This indicates that the worktable 9 is positioned in the feed rack 3. Any known mechanism can be used to enable the worktable 9 to reciprocate. For example, the worktable 9 can be supported by a track or similar structure to allow it to slide along the X-axis, and reciprocating movement can be achieved using a belt and pulley, chain and sprocket, rack and pinion, cylinder, or ball screw. The worktable 9 has fine holes formed on its surface, and an suction mechanism (not shown) draws air through these holes, thereby adsorbing and holding the sheet material placed on its surface.

[0037] Two cutting mechanisms 11 are configured on the processing table 2. Each cutting mechanism 11 includes: a lifting mechanism 12, which holds the cutting blade 10 and moves it along the Z-axis; a left-right moving mechanism 13, which moves the lifting mechanism 12 along the Y-axis; and a front-back moving mechanism 14, which moves the left-right moving mechanism 13 along the X-axis. The left-right moving mechanism 13 and the front-back moving mechanism 14 constitute a parallel moving mechanism that moves the cutting blade 10 parallel to the surface of the worktable 9.

[0038] The lifting mechanism 12 can move the cutting blade 10 in a direction intersecting the surface of the worktable 9 between the position where the cutting blade 10 contacts the worktable 9 and the position where it separates from the sheet placed on the worktable 9. The left-right moving mechanism 13 and the front-back moving mechanism 14 can move the cutting blade 10 parallel to the sheet placed on the worktable 9 at either the position where the cutting blade 10 contacts the worktable 9 or the position where it separates from the sheet placed on the worktable 9.

[0039] A conveying mechanism 15 is provided on the loading / unloading rack 3. The conveying mechanism 15 includes: a holding part 16 for adsorbing and holding the sheet; a lifting part 17 for moving the holding part 16 in the Z-axis direction; and a moving part 18 for moving the holding part 16 and the lifting part 17 in the X-axis direction. The holding part 16 has an adsorption plate with multiple tubes arranged to attract air, which can adsorb and hold the sheet on the lower surface of the adsorption plate. The lifting part 17 holds the holding part 16 horizontally and supports it so that it can move in the Z-axis direction while the sheet is adsorbed and held by the holding part 16. The moving part 18 includes a frame 19 that supports the lifting part 17 and a track 20 that supports the frame 19 in a manner that allows it to move in the X-axis direction. When the sheet is separated from the worktable 9 while it is adsorbed and held by the holding part 16, the holding part 16 and the lifting part 17 can move in the X-axis direction.

[0040] In the conveyor 3, the conveying mechanism 15 places the sheet held in the holding part 16 onto the worktable 9. Simultaneously with stopping the adsorption of the holding part 16, the worktable 9 begins to draw in the sheet, holding it in place and separating the holding part 16 from the sheet. After processing the sheet, the holding part 16 comes into contact with the sheet, and simultaneously with stopping the drawing in the worktable 9, the holding part 16 begins to hold the sheet, separating it from the worktable 9.

[0041] The mechanism for moving the holding part 16 in the lifting part 17 and the mechanism for moving the lifting part 17 in the moving part 18 can use any known mechanism. The holding part 16 and the lifting part 17 are supported by a track or linear shaft, etc., so that they can move, and are moved by belts and pulleys, chains and sprockets, racks and pinions, cylinders, or ball screws, etc.

[0042] The conveying mechanism 15 is capable of moving the sheet material between the worktable 9 located on the X-axis side of the loading / unloading platform 3 and the side of the loading / unloading platform 3 opposite to the processing table 2. On the X-axis side of the loading / unloading platform 3, for example, there are tables for unprocessed sheets (not shown) and tables for processed sheets that reciprocate in the Y-axis direction. The conveying mechanism 15 holds a sheet material on the table for unprocessed sheets and places it on the worktable 9, moving the sheet material processed by the processing table 2 from the worktable 9 to the table for processed sheets.

[0043] On the loading / unloading rack 3, at the end in the X-axis direction where it does not interfere with the holding part 16 which moves up and down in position on the worktable 9, a camera 21 serving as a shooting device is provided. The camera 21 is supported by a support 22 so that it can move in the Y-axis direction and stop at any position. The camera 21 is supported with the orientation of shooting the sheet held in the holding part 16 from below. By moving the camera 21 to any position in the Y-axis direction and moving the holding part 16 to any position in the X-axis direction, it is possible to shoot at any position on the back side of the sheet.

[0044] The sheet processing apparatus 1 includes a control device 25, which controls the processing table 2 and the feed table 3. The control device 25 coordinates the cutting mechanism 11 of the processing table 2, the conveying mechanism 15 of the feed table 3, and the worktable 9 to form a cut surface on the sheet.

[0045] Figure 2 This is a structural diagram of the cutting mechanism involved in Embodiment 1. Figure 2 This is a cross-sectional view of the lifting mechanism 12 and the left-right moving mechanism 13 of the cutting mechanism 11, viewed along the Y-axis. Figure 2 The forward and backward movement mechanism 14 is not shown. The cutting mechanism 11 includes a cutting blade 10, a cutter bracket 30, a cutter shaft 40, a sleeve 50, a pulley 51, a detection plate 52, a sensor 53, a housing 55, an eccentric cam 60, a compression spring 65, a vibration motor 110, an angle adjustment motor 120 as an angle control mechanism, a pulley 121, and a timing belt 122.

[0046] The cutting blade 10 is detachably mounted on the cutter bracket 30. The cutter bracket 30 is fixed to the cutter shaft 40. The cutter shaft 40 is held within the sleeve 50 in a manner that allows it to move along the central axis direction (Z-axis direction) of a groove with a specified stroke. The sleeve 50 is held within the housing 55 so that it can rotate about the central axis of the cutter shaft 40. A pulley 51 is coaxially fixed to the sleeve 50. The pulley 51 is connected to a pulley 121 coaxially fixed to the rotating shaft of the angle adjustment motor 120 via a timing belt 122. A detection plate 52 is fixed to the pulley 51, and a sensor 53 detects the detection plate 52.

[0047] The rotation of the angle-adjusting motor 120 causes the pulley 121 to rotate. This rotation of the pulley 121, in turn, causes the pulley 51 and the sleeve 50 fixed to it to rotate via the timing belt 122. As the sleeve 50 rotates, the cutter shaft 40 also rotates within the sleeve 50, causing the cutter blade 10, held in the cutter bracket 30, to rotate around the Z-axis. The amount of rotation of the cutter blade 10 can be measured by the sensor 53 detecting the detection plate 52.

[0048] A vibration motor 110 is fixed to the upper part of the housing 55. An eccentric cam 60 is fixed to the rotating shaft of the vibration motor 110. The eccentric cam 60 is disposed on the upper part of the cutter shaft 40. The cutter shaft 40 is subjected to an upward force by a compression spring 65 with its upper end abutting against the eccentric cam 60.

[0049] When the vibration motor 110 rotates, the eccentric cam 60 rotates, and the cutter shaft 40, which abuts against the eccentric cam 60, reciprocates along its axial direction. As a result, the cutter 10 vibrates in the axial direction of the cutter shaft 40.

[0050] The housing 55 is fixed to the base 75. A slider 150a is fixed to the base 75. The slider 150a extends along the Z-axis and is slidably held on the track 150b fixed to the frame 151. A rack 80 extending along the Z-axis is fixed to the base 75. A pinion 70 meshes with the rack 80. The pinion 70 is driven by a vertically moving motor 130 fixed to the frame 151.

[0051] If the up-and-down moving motor 130 rotates, the pinion 70 rotates, causing the rack 80 to move in the Z-axis direction. As the rack 80 moves, the base 75 also moves in the Z-axis direction, causing the cutting blade 10 held on the base 75 to move in the Z-axis direction.

[0052] Frame 151 is supported on movable beam 1200 in a manner that allows it to move in the Y-axis direction and stop at any position. For example, a slider 160a is fixed to frame 151, and a track 160b extending along the Y-axis direction is fixed to movable beam 1200. Slider 160a is slidably mounted on track 160b. Rack 100 is fixed to movable beam 1200. Pinion 90 meshing with rack 100 is connected to the rotation shaft of lateral movement motor 140 fixed to frame 151. When lateral movement motor 140 rotates, pinion 90 rotates, and frame 151 moves along movable beam 1200 in the Y-axis direction. Movable beam 1200 is supported for passage Figure 1 The forward and backward moving mechanism 14 can move in the X-axis direction and can stop at any position.

[0053] The control device 25 moves the cutting blade 10 to the starting point of the cut surface formed on the sheet, and orients the cutting blade 10 in a direction parallel to the extension direction of the cut surface. Then, the cutting blade 10 is lowered to a position contacting the worktable 9 to penetrate the sheet, and the cutting blade 10 is moved along the extension direction of the cut surface, thereby forming a cut surface on the sheet. During the formation of the cut surface, a vibration motor can also be driven to vibrate the cutting blade 10 in the Z-axis direction.

[0054] For example, by aligning the blade of the cutting blade 10 parallel to the X-axis and moving the movable beam 1200 along the X-axis while fixing the position of the cutting blade 10 in the Y-axis direction, a cut surface extending along the X-axis direction can be formed. If the blade of the cut surface is aligned parallel to the Y-axis and the frame 151 is moved along the Y-axis while fixing the position of the cutting blade 10 in the X-axis direction, a cut surface extending along the Y-axis direction can be formed. Furthermore, by coordinating the operation of the left-right movement mechanism 13, the front-back movement mechanism 14, and the angle control mechanism simultaneously, a cut surface with an arbitrary curve intersecting the sheet surface can be formed.

[0055] A cutting blade wear determination device 31 is assembled in the control device 25 of the sheet processing device 1. Figure 3 This is a block diagram illustrating a structural example of the cutting blade wear determination device according to Embodiment 1. The cutting blade wear determination device 31 includes a cutting surface information storage unit 32, a cutting control unit 33, a cutting mark extraction unit 34, and a determination unit 35. The cutting blade wear determination device 31 is connected to the cutting mechanism 11 of the processing table 2, the conveying mechanism 15 of the loading and unloading table 3, the worktable 9, and the drive mechanism 36 and camera 21 of the drive camera 21. The cutting surface information storage unit 32 stores cutting surface information, including the position and shape of the cutting surface formed on the sheet, and the correspondence between the cutting surface and the cutting blade 10 that forms the cutting surface. The cutting control unit 33 controls the drive mechanism 36 to form a cutting surface on the sheet according to the cutting surface information stored in the cutting surface information storage unit 32.

[0056] After the sheet, for which the cut surface has been indicated, is separated from the worktable 9 by the conveying mechanism 15, the cutting control unit 33 uses the camera 21 to photograph the back side of the sheet where the cut surface intended for the extraction of cutting marks is indicated. The cut surface for which cutting marks are to be extracted is stored in the cut surface information storage unit 32. The cutting mark extraction unit 34 acquires the image obtained by photographing the back side of the sheet where the cut surface intended for the formation is indicated, and extracts the cutting marks from the image as lines intersecting the formed cut surface with the back side of the sheet. Since the position of the cut surface and the area captured in the image are fixed, the cutting mark extraction unit 34 can easily extract the cutting marks.

[0057] The determination unit 35 compares a hypothetical line with the cutting mark extracted by the cutting mark extraction unit 34 for the cut surface of the object from which the cutting mark is extracted. The hypothetical line is imagined to be the line formed by the cutting blade 10 on the cut surface of the sheet intersecting the back side of the sheet. If the hypothetical line matches the cutting mark, the determination unit 35 determines that the cutting blade 10, which indicates the formation of the cut surface, has not been worn. If the hypothetical line does not match the cutting mark, the determination unit 35 determines that the cutting blade 10, which indicates the formation of the cut surface, has been worn. For example, if the cutting mark is shorter than the hypothetical line, interrupted in the middle, or has no cutting mark at all, it is determined that the cutting blade 10 has been worn. Alternatively, if the hypothetical line is a single line, and the cutting mark is double or has a wide portion, it is determined that the cutting blade 10 has been worn.

[0058] The cut surface of the object from which the cutting marks are extracted is set separately for the cutting blade 10 provided by the sheet processing device 1. Figure 4 This is a diagram illustrating an example of sheet material processing. In Figure 4 In the diagram, solid lines represent the hypothetical cut surface C, and dashed lines represent the indentation lines used for bending the sheet W. Although in Figure 1 The indentation mechanism is omitted in the original text, but the sheet processing device 1 can also be equipped with an indentation mechanism. Figure 4 In the example, the cut surface C is depicted as continuous, but in reality, there are uncut parts everywhere, and the cut surface C is formed in such a way that the processed product cut from the sheet W and the blank of the sheet W are not separated in the sheet processing apparatus 1.

[0059] When the sheet processing apparatus 1 is equipped with two cutting mechanisms 11, for example, Figure 4 The left and right directions are the X-axis directions, and the cutting mechanism 11 is used to form the shape by approaching the entry and exit of the table 3. Figure 4 The right half of the cut surface is formed by the cutting mechanism 11 located away from the feed table 3, forming the left half of the cut surface. The cut surface of the object from which the cutting marks are extracted is selected and set from the cut surfaces formed by each cutting blade 10. The cutting control unit 33 causes the camera 21 to capture images of the back side of the sheet material at the cut surface of the set object. The cutting mark extraction unit 34 acquires images of the back side of the sheet material at the cut surface of the object and extracts the cutting marks.

[0060] Figure 5This is a flowchart illustrating an example of the operation of the cutting blade wear determination according to Embodiment 1. The cutting blade wear determination is initiated at a timed interval to determine whether the cutting blade 10 has experienced wear. For example, the cutting blade wear determination can be initiated for each sheet, or for each bundle of sheets being processed. Alternatively, it can be initiated according to a predetermined number of sheets, or according to a random number of sheets. Without performing the cutting blade wear determination, the back side of the sheet is not photographed, the cutting marks are not extracted, and the imagined line is not compared with the cutting marks; only the cut surface is formed.

[0061] The cutting control unit 33 instructs the formation of a cut surface containing the cut surface of the object from which the cutting marks are to be extracted (step S10). After the cut surface is formed on the sheet, the cutting control unit 33 takes a picture of the back side of the sheet at the portion where the cut surface of the object is to be formed (step S11). The cutting mark extraction unit 34 acquires an image obtained by taking a picture of the back side of the sheet at the portion where the cut surface of the object is to be formed, and extracts the cutting marks from the image (step S12).

[0062] The determination unit 35 compares the hypothetical line with the cutting mark extracted by the cutting mark extraction unit 34 (step S13). The hypothetical line is imagined to be the line formed by the cutting blade 10 on the cut surface of the sheet and the back surface of the sheet. If the hypothetical line and the cutting mark are inconsistent (step S14: No), it is determined that the cutting blade 10, which forms a cut surface where the cutting mark and the hypothetical line are inconsistent, has been worn (step S15), and it is indicated that the cutting blade 10 has been worn. Furthermore, a stop command may be issued or an alarm may be issued to the operator. If the hypothetical line and the cutting mark are consistent (step S14: Yes), it is not determined that the cutting blade is worn and the process ends.

[0063] As explained above, according to the sheet processing apparatus 1 of Embodiment 1, a cutting mark, which is the intersection line between the back side of the sheet and the cut surface, is extracted from an image of the back side of the sheet where the cut surface is formed by the cutting blade 10. If the line intersecting the indicated cut surface and the back side of the sheet, i.e., the hypothetical line, is inconsistent with the extracted cutting mark, it is determined that the cutting blade 10 has been worn. Therefore, the wear of the cutting blade 10 can be reliably detected. As a result, the generation of defective products can be suppressed, and the useless wear of the cutting blade 10 can be avoided, thereby improving operating efficiency.

[0064] When the sheet processing apparatus 1 is equipped with two or more cutting blades 10, wear determination of all cutting blades 10 may not be performed on a single sheet. Alternatively, wear determination may be performed on each cutting blade 10 at different cycles.

[0065] Implementation method 2.

[0066] Figure 6This is a schematic perspective view of the sheet processing apparatus according to Embodiment 2 of the present invention. The sheet processing apparatus 1 of Embodiment 2 includes three processing tables 4, 5, and 6 arranged in series, and two entry / exit tables 7 and 8 arranged before and after the processing tables. Figure 6 The cutting mechanism 11 of the processing table, the holding part 16 of the conveying mechanism 15, and the moving part 18 are omitted.

[0067] The third processing table 6 and the subsequent feed table 8 have the same structure as the processing table 2 and feed table 3 in Embodiment 1. In Embodiment 2, the worktable 9 typically does not move from the subsequent feed table 8 to the third processing table 6. The worktable 9 moves sequentially from the preceding feed table 7 through the first processing table 4, the second processing table 5, and the third processing table 6 to the subsequent feed table 8. In the subsequent feed table 8, after the processed sheet is separated from the worktable 9, the worktable 9 is transferred to the preceding feed table 7 via other paths, such as below each processing table.

[0068] In the preceding feed rack 7, the unprocessed sheet is placed on the worktable 9, and the worktable 9 holding the sheet moves toward the first processing rack 4. The first processing rack 4 and the second processing rack 5 each have multiple cutting mechanisms 11, capable of simultaneously forming multiple cutting surfaces. On the first processing rack 4, a cutting surface extending along the X-axis is formed; on the second processing rack 5, a cutting surface extending along the Y-axis is formed. On the third processing rack 6, cutting surfaces in an inclined direction and on a curved surface are formed. The first processing rack 4, the second processing rack 5, and the third processing rack 6 simultaneously and in parallel form cutting surfaces on the sheet.

[0069] After the cutting surface is formed on the third processing table 6, the worktable 9 moves to the subsequent loading / unloading table 8. The subsequent loading / unloading table 8, as in Embodiment 1, is equipped with a camera 21. In the subsequent loading / unloading table 8, when the sheet is separated from and transported from the worktable 9, the camera 21 captures images of the back side of the sheet. In Embodiment 2, for all the cutting blades 10 provided on the first processing table 4 to the third processing table 6, the camera 21 of the subsequent loading / unloading table 8 captures images of the back side of the sheet at the portion where the cutting surface has been indicated.

[0070] The cutting mark extraction unit 34 extracts the cutting marks of the cut surface formed by each cutting blade 10 from the image. The determination unit 35 determines that the cutting blade 10 that indicates the formation of the cut surface has been worn if the imagined line of the cut surface formed by the cutting blade 10 is inconsistent with the cutting mark of the formed cut surface.

[0071] Figure 7This diagram illustrates an example of the cutting surfaces involved in Embodiment 2. In Embodiment 2, unlike the cutting surface C that forms the processed product cut from the sheet W, cutting surfaces P, Q, and R are formed in the blank areas of the sheet W. For example, the first processing table 4 is equipped with eight cutting blades 10, and each cutting blade 10 forms a cutting surface P extending in the X-axis direction in the blank areas of the sheet W. The second processing table 5 is equipped with eight cutting blades 10, and each cutting blade 10 forms a cutting surface Q extending in the Y-axis direction in the blank areas of the sheet W. The third processing table 6 is equipped with two cutting blades 10, and each cutting blade 10 forms an inclined cutting surface R in the blank areas of the sheet W.

[0072] The cutting mark extraction unit 34 acquires an image obtained by the camera 21 capturing the back side of the sheet where the blank cutting surface is indicated, and extracts the cutting marks formed on the blank cutting surface from the image. Figure 7 In the example, the sheet is stopped at a position directly above the camera 21 on the blank cut surface P formed by the first processing table 4, and the camera 21 is moved from the center of the sheet outwards while capturing images of the back side of the sheet. Next, the camera 21 is stopped at positions on the blank cut surfaces Q and R formed by the second processing table 5 and the third processing table 6, and the sheet is moved using the transport mechanism 15 while capturing images of the back side of the sheet. The cutting mark extraction unit 34 extracts the cutting marks formed on the blank cut surfaces P, Q, and R from the obtained multiple images.

[0073] The number of images captured does not need to be the same as the number of cutting blades 10; multiple cutting marks can be captured in a single image. Since the location of the blank cut surface and the area captured in the image are known, the cutting mark extraction unit 34 can easily extract the cutting marks. If the determination unit 35 determines that the cutting blade 10 indicating the formation of the blank cut surface has been worn when the imagined line formed on the blank cut surface is inconsistent with the cutting mark formed on the blank cut surface, the determination unit 35 determines that the cutting blade 10 indicating the formation of the cut surface has been worn.

[0074] In Embodiment 2, furthermore, if the determination unit 35 determines that a certain cutting blade 10 has been worn out, the cutting control unit 33, starting from the sheet to be processed next, replaces one of the multiple cutting blades 10 that was not determined to be worn out with the one that was determined to be worn out, thus forming a predetermined cut surface formed by the cutting blade 10 that was determined to be worn out. In this way, sheet processing can continue until at least the bundle of unprocessed sheets provided on the feed tray 7 in the previous stage disappears.

[0075] For example, if it is determined that one of the eight cutting blades 10 of the first processing table 4 has worn out, one of the remaining seven cutting blades 10 can be used to replace it to form the cut surface intended to be formed by that cutting blade 10. The replacement cutting blade 10 is not limited to one piece; it can be formed by multiple cutting blades 10 sharing the task. The replacement cutting blade 10 is not limited to the cutting blade 10 of the processing table to which the worn cutting blade 10 belongs. For example, the cut surface intended to be formed by the worn cutting blade 10 of the first processing table 4 can also be formed by the cutting blade 10 of the third processing table 6.

[0076] The replacement of the worn-out cutting blade 10 can be determined in a way that minimizes the sheet processing time. For example, the time from when the sheet is fed into the feed tray 7 in the previous stage to when the sheet is removed from the feed tray 8 in the subsequent stage is minimized, that is, the throughput of the sheet processing device 1 is maximized, and the cut surfaces formed by the cutting blade 10 are reassembled instead.

[0077] If the determination unit 35 determines that a certain cutting blade 10 has suffered wear, the determination unit 35 or the cutting control unit 33 rewrites the cutting surfaces associated with the determined worn cutting blade 10 stored in the cutting surface information storage unit 32 with cutting blades 10 that replace the cutting blades 10 that formed them. Starting from the sheet to be processed next, the cutting control unit 33 forms cutting surfaces from the cutting blades 10 that were not determined to have suffered wear, according to the rewritten association between the cutting surfaces and the cutting blades 10. For cutting surfaces used for wear determination formed in blank areas of the sheet, the cutting control unit 33 does not form cutting surfaces corresponding to the determined worn cutting blades 10.

[0078] In Embodiment 2, if it is determined that a certain cutting blade 10 has been worn out, the processing of the sheet can continue without interrupting the processing of that batch, and the cutting blade 10 can be replaced at an appropriate time. When the cutting blade 10 is replaced, the association between the cutting surface stored in the cutting surface information storage unit 32 and the cutting blade 10 that forms the cutting surface is restored to the association when the cutting blade 10 is normal.

[0079] Figure 8This is a flowchart illustrating an example of the operation for determining the wear of the cutting blade according to Embodiment 2. The cutting control unit 33 instructs the formation of a cut surface for the processed product cut from the sheet and a blank cut surface for determining the wear of the cutting blade 10 (step S20). After the cut surface is formed on the sheet, the cutting control unit 33 takes a picture of the back side of the sheet where the blank cut surface is formed (step S21). The cutting trace extraction unit 34 acquires an image obtained by the camera 21 of the back side of the sheet where the blank cut surface is formed, and extracts the cutting trace from the image (step S22).

[0080] The determination unit 35 selects one cutting blade 10 from the plurality of cutting blades 10 (step S23), and compares the imagined line formed on the blank cutting surface by the cutting blade 10 with the cutting mark formed on the blank cutting surface by the cutting blade 10 (step S24). If the imagined line and the cutting mark are inconsistent (step S25: No), it is determined that the selected cutting blade 10 has been worn (step S26). If the imagined line and the cutting mark are consistent (step S25: Yes), it is not determined that the cutting blade is worn. In either case, if there are unselected remaining cutting blades 10 (step S27: Yes), the process returns to step S23 and repeats the process starting from the selection of the cutting blade 10.

[0081] For all cutting blades 10, the comparison of the envisioned line and the cutting mark ends. If there are no unselected cutting blades 10 remaining (step S27: No), then for the cutting surfaces stored in the cutting surface information storage unit 32 associated with the cutting blades 10 determined to have suffered wear, the cutting blades 10 that formed them are rewritten (step S28). As a result, starting from the sheet to be processed, the cutting control unit 33 forms cutting surfaces using cutting blades 10 that were not determined to have suffered wear, according to the rewritten association between the cutting surfaces and the cutting blades 10. If there are no cutting blades 10 determined to have suffered wear, then step S28 is not actually executed.

[0082] As explained above, in the sheet processing apparatus 1 of Embodiment 2, since a cut surface for loss determination is formed in the blank space of the sheet, unlike the cut surface used to form the processed product cut from the sheet, it is possible to perform image capture for loss determination and extraction of cutting marks more quickly. Furthermore, by using one of the multiple cutting blades 10 that has not been determined to be worn to form the cut surface that was determined to be worn, sheet processing can continue without interrupting the batch processing, and the cutting blade 10 can be replaced at appropriate intervals.

[0083] In Embodiment 2, the cutting blade wear determination can be initiated either for each sheet or for each bundle of sheets being processed. Alternatively, it can be initiated according to a predetermined number of sheets or a random number of sheets. Without cutting blade wear determination, the back side of the sheet is not photographed, the cutting marks are not extracted, and the imagined line is not compared with the cutting marks; only the cut surface is formed. In Embodiment 2, wear determination for all cutting blades 10 may not be performed on a single sheet. Alternatively, wear determination may be performed for each cutting blade 10 at different cycles.

[0084] The method of determining the wear of the cutting blade 10 by replacing any other cutting blade 10 that has not been determined to be worn with a cutting blade 10 is not limited to the method of determining the wear of the cutting blade 10 by comparing the cutting mark with the intended line. It can also be combined with the method of determining the wear of the cutting blade 10 based on other methods. For example, the method of determining the wear of the tip based on measuring the height of the cutting blade 10, the method of determining the chipping of the cutting blade 10 based on the image of the cutting blade 10, or the method of determining the passivation of the cutting blade 10 by the change in the contact resistance between the blade tip and the electrode, or a combination thereof, can be combined with the replacement of the worn cutting blade.

[0085] In this embodiment, a single camera 21 is envisioned as the imaging device to capture images of the back of the sheet, but multiple cameras 21 may also be provided in the sheet processing apparatus 1. Furthermore, the camera 21 is not limited to a typical aspect ratio field of view; it may also have a field of view that is horizontally or vertically elongated. Alternatively, the imaging device may be a structure similar to an image sensor in an image reading device, which takes in a line of pixels along the main scanning direction and performs sub-scanning using the transport mechanism 15.

[0086] Figure 9 This is a block diagram illustrating an example of the hardware structure of the cutting blade wear determination device according to the embodiment. The cutting blade wear determination device 31 includes a control unit 41, a main storage unit 42, an external storage unit 43, an operation unit 44, a display unit 45, an input / output unit 46, and a transceiver unit 47. The main storage unit 42, the external storage unit 43, the operation unit 44, the display unit 45, the input / output unit 46, and the transceiver unit 47 are all connected to the control unit 41 via an internal bus 40.

[0087] The control unit 41 is composed of a CPU (Central Processing Unit) and other components. According to the control program 48 stored in the external storage unit 43, it executes the processing of the cutting surface information storage unit 32, the cutting control unit 33, the cutting mark extraction unit 34, and the determination unit 35 of the cutting blade wear determination device 31.

[0088] The main storage unit 42 is composed of RAM (Random-Access Memory) and the like, and loads the control program 48 stored in the external storage unit 43, which is used as the working area of ​​the control unit 41.

[0089] The external storage unit 43 is composed of non-volatile memory such as flash memory, hard disk, DVD-RAM (Digital Versatile Disc Random-Access Memory), DVD-RW (Digital Versatile Disc ReWritable), etc. It stores data such as the program used by the control unit 41 to perform the cutting blade wear determination device 31 and cutting surface information. In addition, according to the instructions of the control unit 41, the data stored in the program is supplied to the control unit 41, and the data supplied from the control unit 41 is stored.

[0090] The operation unit 44 consists of a keyboard and mouse, and an interface device that connects the keyboard and mouse to the internal bus 40. The operation unit 44 inputs and supplies to the control unit 41 information such as the specification of the cutting surface for determining the wear of the cutting blade, the correspondence between the cutting surface formed on the blank of the sheet and the cutting blade 10 that forms the cutting surface.

[0091] The display unit 45 is composed of an LCD (Liquid Crystal Display) or an organic EL display, etc., and displays the worn-out cutting blade 10, the replacement cutting blade 10, etc.

[0092] The input / output unit 46 is configured with a serial interface or a parallel interface. A drive mechanism 36 and a camera 21 are connected to the input / output unit 46. The control unit 41 instructs the formation of the cut surface and the shooting via the input / output unit 46 to obtain an image of the back side of the sheet.

[0093] The transceiver unit 47 consists of a network terminal device or wireless communication device connected to a network, and a serial interface or LAN (Local Area Network) interface connected to them. The transceiver unit 47 downloads sheet processing data or control program 48 via the network.

[0094] Figure 3 The cutting surface information storage unit 32, cutting control unit 33, cutting mark extraction unit 34, and determination unit 35 of the cutting blade wear determination device 31 shown are processed by the control program 48, which uses the control unit 41, main storage unit 42, external storage unit 43, operation unit 44, display unit 45, input / output unit 46, and transceiver unit 47 as resources.

[0095] Furthermore, the structure of the cutting blade wear determination device 31 described in each embodiment is an example and can be arbitrarily changed and modified. The structure of the cutting blade wear determination device 31 is not limited to the structure shown in the embodiments. For example, a smartphone or tablet terminal can also be used as the cutting blade wear determination device 31. In addition, the cutting blade wear determination device 31 can be installed on a network, and the function of the cutting blade wear determination device 31 can be provided via the network.

[0096] Furthermore, the aforementioned hardware structure and flowchart are examples that can be arbitrarily changed and modified.

[0097] The central part of the cutting blade wear determination device 31, which consists of a cutting surface information storage unit 32, a cutting control unit 33, a cutting mark extraction unit 34, and a determination unit 35, does not rely on a dedicated system and can be implemented using a conventional computer system. For example, the computer program for performing the above actions can be stored and distributed on a computer-readable recording medium (USB memory, CD-ROM, DVD-ROM, etc.), and the cutting blade wear determination device 31 performing the above processing can be constructed by installing the computer program into a computer. Alternatively, the computer program can be stored in the storage device of a server device on a communication network such as the Internet, and the cutting blade wear determination device 31 can be constructed by downloading it through a conventional computer system.

[0098] Alternatively, in cases where the cutting tool wear determination device 31 is implemented by sharing the burden between the OS (operating system) and the application, or by the collaboration between the OS and the application, only the application portion may be stored on the recording medium or storage device.

[0099] Alternatively, a computer program can be overlaid on a carrier wave and published via a communication network. For example, the computer program can be announced on a bulletin board system (BBS) on a communication network and published via the network. Furthermore, the computer program can be configured to start and execute like other applications under the control of the operating system, thereby enabling the aforementioned processing to be performed.

[0100] This invention can be implemented and modified in various ways without departing from its broad spirit and scope. Furthermore, the above-described embodiments are illustrative of the invention and do not limit its scope. That is, the scope of the invention is defined not by the embodiments, but by the claims. Moreover, various modifications implemented within the scope of the claims and their equivalents are considered to be within the scope of the invention.

[0101] This application is based on Japanese Patent Application No. 2021-133375, filed on August 18, 2021. The entire description, claims, and drawings of Japanese Patent Application No. 2021-133375 are incorporated herein by reference.

[0102] Explanation of reference numerals in the attached figures

[0103] 1: Sheet processing equipment

[0104] 2: Processing stand

[0105] 3: Moving items onto the shelf

[0106] 4: First processing table

[0107] 5: Second processing table

[0108] 6: Third processing stand

[0109] 7: Preamplifier mounting rack

[0110] 8: Power amplifier mounting rack

[0111] 9: Workbench

[0112] 10: Cutting knife

[0113] 11: Cutting mechanism

[0114] 12: Lifting mechanism

[0115] 13: Left and right moving mechanism (parallel moving mechanism)

[0116] 14: Forward and backward moving mechanism (parallel moving mechanism)

[0117] 15: Conveying mechanism

[0118] 16: Maintaining Section

[0119] 17: Lifting Unit

[0120] 18: Mobile Department

[0121] 19: Frame (Moving Part)

[0122] 20: Track (Moving Part)

[0123] 21: Camera (filming device)

[0124] 22: Support section

[0125] 25: Control device

[0126] 31: Cutting blade wear determination device

[0127] 32: Cross-section information storage unit

[0128] 33: Cut-off Control Unit

[0129] 34: Section for extracting cutting marks

[0130] 35: Judgment Department

[0131] 36: Drive mechanism

[0132] 41: Control Department

[0133] 42: Main Storage Section

[0134] 43: External Storage Section

[0135] 44: Operations Department

[0136] 45: Display Section

[0137] 46: Input / Output Section

[0138] 47: Receiving and Dispatch Department

[0139] 48: Control program.

Claims

1. A sheet processing apparatus, comprising: A worktable that holds the sheet placed on the surface; A cutting blade capable of forming a cutting surface from the surface to the back side on a sheet held on the surface of the worktable; A lifting mechanism that enables the cutting blade to move in a direction intersecting the surface of the worktable between the position where the cutting blade contacts the worktable and the position where it separates from the sheet placed on the worktable. A parallel movement mechanism that enables the cutting blade to move parallel to the surface of the worktable while in contact with it. A conveying mechanism capable of placing and separating the sheet from the worktable, and capable of moving the sheet while it is separated from the worktable; The cutting control unit operates the parallel movement mechanism and the lifting mechanism, and instructs the cutting blade to form a cutting surface on the sheet placed on the worktable. A photographing device that photographs the back side of a sheet after the sheet, in which the cut surface has been indicated, has been separated from the worktable by the conveying mechanism. The cutting trace extraction unit, while the sheet after the formation of the indicated cutting surface is separated from the worktable, acquires an image of the back side of the sheet where the cutting surface has been formed, which is captured by the imaging device, and extracts the cutting trace from the image as a line intersecting the formed cutting surface with the back side of the sheet. as well as The determination unit determines that the cutting blade, which was indicated to form the cutting surface of the sheet, has been worn if the line (i.e., the line formed by the cutting blade on the cutting surface of the sheet and the back side of the sheet) is inconsistent with the cutting mark extracted by the cutting mark extraction unit.

2. The sheet processing apparatus according to claim 1, wherein, The cutting control unit, unlike the cutting surface used to form the processed product cut from the sheet, instructs the formation of a cutting surface in a blank area of ​​the sheet. The cutting mark extraction unit acquires an image of the back side of a sheet material where the blank cut surface is indicated, captured by the imaging device, and extracts the cutting marks formed on the blank cut surface from the image. If the imagined line formed on the blank cut surface is inconsistent with the cut mark formed on the blank cut surface, the determination unit determines that the cutting blade that indicated the formation of the cut surface has been worn.

3. The sheet processing apparatus according to claim 1 or 2, wherein, The sheet processing apparatus includes a plurality of cutting blades, which are capable of independently forming a cut surface from the surface to the back side on the sheet held on the surface of the worktable. The cutting control unit instructs each of the cutting blades to form different cutting surfaces. The cutting mark extraction unit extracts the cutting marks formed by the cutting surface of each cutting blade from the image. If, for each of the cutting blades, the determination unit determines that the cutting blade for which the cutting surface was formed has been worn out, the assumed line of the cut surface formed by the cutting blade is inconsistent with the cutting mark of the cut surface formed.

4. The sheet processing apparatus according to claim 3, wherein, The sheet processing apparatus includes multiple parallel movement mechanisms and multiple lifting mechanisms that enable the cutting blades to move independently of each other. If the determination unit determines that one of the cutting blades has been worn out, the cutting control unit will replace one of the plurality of cutting blades that has not been determined to be worn out, starting from the sheet to be processed, to form a predetermined cut surface formed by the cutting blade that was determined to be worn out.

5. A cutting blade wear determination device, comprising: The cutting control unit operates the lifting mechanism and the parallel movement mechanism, and instructs the formation of a cutting surface on the sheet held by the worktable. The lifting mechanism enables the cutting blade to move in a direction intersecting the surface of the worktable between the position where the cutting blade contacts the worktable and the position where it separates from the sheet placed on the worktable. The cutting blade is capable of forming the cutting surface that extends from the surface of the sheet placed on the surface of the worktable and held by the worktable to the back side. The parallel movement mechanism enables the cutting blade to move parallel to the surface of the worktable while in contact with it. A cutting mark extraction unit, in a state where a sheet, after the formation of the indicated cutting surface, has been separated from the worktable by a conveying mechanism, acquires an image of the back side of the sheet at the portion where the cutting surface has been formed, captured by an imaging device, and extracts from the image the cutting mark, which is a line intersecting the formed cutting surface with the back side of the sheet. The conveying mechanism is capable of separating the sheet placed on the worktable from the worktable and moving the sheet while it is separated from the worktable. The determination unit determines that the cutting blade, which was indicated to form the cutting surface of the sheet, has been worn if the line (i.e., the line formed by the cutting blade on the cutting surface of the sheet and the back side of the sheet) is inconsistent with the cutting mark extracted by the cutting mark extraction unit.

6. A method for determining cutting blade wear, wherein the method for determining cutting blade wear is performed by a cutting blade wear determination device, wherein... The method for determining the wear of the cutting blade includes: The cutting control step activates the lifting mechanism and the parallel movement mechanism, and instructs the formation of a cutting surface on the sheet held by the worktable. The lifting mechanism enables the cutting blade to move in a direction intersecting the surface of the worktable between a position in contact with the worktable and a position separated from the sheet placed on the worktable. The cutting blade is capable of forming the cutting surface extending from the surface of the sheet placed on the surface of the worktable and held by the worktable to the back side. The parallel movement mechanism enables the cutting blade to move parallel to the surface of the worktable while in contact with it. The cutting mark extraction step involves, with the sheet after the indicated cutting surface has been formed separated from the worktable by a conveying mechanism, acquiring an image of the back side of the sheet at the portion where the indicated cutting surface has been formed, captured by an imaging device, and extracting the cutting mark from the image as a line intersecting the formed cutting surface with the back side of the sheet. The conveying mechanism is capable of placing and separating the sheet from the worktable, and can move the sheet while it is separated from the worktable. In the determination step, if the line that is assumed to be formed by the cutting blade on the cutting surface of the sheet and the back side of the sheet intersects with the cutting mark extracted in the cutting mark extraction step, it is determined that the cutting blade that indicated the formation of the cutting surface has been worn.

7. A computer program product for causing a computer to perform the following steps: The cutting control step activates the lifting mechanism and the parallel movement mechanism, and instructs the formation of a cutting surface on the sheet held by the worktable. The lifting mechanism enables the cutting blade to move in a direction intersecting the surface of the worktable between a position in contact with the worktable and a position separated from the sheet placed on the worktable. The cutting blade is capable of forming a cutting surface extending from the surface of the sheet placed on the worktable and held by the worktable to the back side. The parallel movement mechanism enables the cutting blade to move parallel to the surface of the worktable while in contact with it. The cutting mark extraction step involves, with the sheet after the indicated cutting surface has been formed separated from the worktable by a conveying mechanism, acquiring an image of the back side of the sheet at the portion where the indicated cutting surface has been formed, captured by an imaging device, and extracting the cutting mark from the image as a line intersecting the formed cutting surface with the back side of the sheet. The conveying mechanism is capable of placing and separating the sheet from the worktable, and can move the sheet while it is separated from the worktable. In the determination step, if the line that is assumed to be formed by the cutting blade on the cutting surface of the sheet and the back side of the sheet intersects with the cutting mark extracted in the cutting mark extraction step, it is determined that the cutting blade that indicated the formation of the cutting surface has been worn.

Images