Corrugated cardboard sheet feeder

Abstract

To reduce occurrence of paper jams when a long-corrugated cardboard raw material is introduced into a cutting part when pulling out the long-corrugated cardboard raw material from a stack of the long-corrugated cardboard raw material folded in an accordion-like shape and stacked, and conveying the same along a transportation passage.SOLUTION: There is provided a corrugated cardboard sheet feeder, wherein a first cutting part 30 constituting the corrugated cardboard sheet feeder is arranged in the middle of a transportation passage 11 and cuts a long-corrugated cardboard raw material 61 at a predetermined length to cut out a corrugated cardboard sheet 62. The first cutting section 30 performs fold-feed sheet cutting in which the long-corrugated cardboard raw material is cut at a third length position that includes the fold and is longer than the sheet length, from a tip when detection means detects presence or absence of a fold that may cause paper jams in a range between a position of a predetermined sheet length from the tip of the long-corrugated cardboard raw material 61 to be conveyed along the transportation passage 11 and a position of a predetermined first length upstream of the position.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a technique for manufacturing cardboard blanks of appropriate lengths and shapes from long cardboard materials.

Background Art

[0002] Conventionally, at work sites where articles to be packed are packed in cardboard, a large number of folded cardboard boxes are prepared in advance. Workers repeatedly perform the operations of unfolding these, assembling them into boxes, putting the articles to be packed and, if necessary, cushioning materials into the boxes, and taping them up. Also, when articles to be packed having different sizes and shapes are mixed, a plurality of types of folded cardboard boxes having different sizes are prepared, and workers select ones according to the size of the articles to be packed.

[0003] A folded cardboard box is manufactured by cutting out the unfolded shape (cardboard blank) of the cardboard of the target size from a regular rectangular plate-shaped cardboard sheet, performing processing such as ruling and grooving, and then fixing the overlapping portions with adhesive or a stapler. However, when it is desired to manufacture cardboard boxes of different sizes, if the unfolded shapes of cardboard boxes of various sizes are cut out from a regular cardboard sheet, it is necessary to set the regular cardboard sheet to a size corresponding to the largest unfolded shape, and in many cases, there is a lot of waste in cutting.

[0004] Therefore, a device has been proposed in which a long cardboard material is manufactured in advance, folded in a bellows shape, and stacked vertically (this stacked long cardboard material is called a long cardboard material stack), and when necessary, a long cardboard material is pulled out by a necessary length (a length corresponding to the unfolded shape of the cardboard box to be manufactured) to cut out a cardboard blank, and a cardboard box is manufactured from the cut-out cardboard blank, and articles are put into the cardboard box to pack the articles (see, for example, Patent Document 1 and Patent Document 2).

Prior Art Documents

Patent Documents

[0005] Patent Document 1 International Publication No. 2014 / 119439 Patent Document 2 Japanese Unexamined Patent Application Publication No. 2019-93619 Summary of the Invention Problems to be Solved by the Invention

[0006] In such an apparatus, a long corrugated cardboard material, a corrugated cardboard blank cut out therefrom, and a corrugated cardboard box assembled therefrom continuously flow on a single conveyor path and are successively processed by various processing units. However, if a problem occurs in any of the processing units, the conveyance of the long corrugated cardboard material is temporarily stopped. In the long corrugated cardboard material drawn out from the long corrugated cardboard material stack, creases are formed at predetermined intervals when it is folded in a bellows shape. If this crease is located close to the tip of the drawn-out long corrugated cardboard material, when the long corrugated cardboard material is introduced into a cutting unit that cuts the long corrugated cardboard material to the required length, the tip of the long corrugated cardboard material is likely to bend when it comes into contact with the guide member. Then, when the tip of the long corrugated cardboard material bends, the thickness of that part doubles, causing a problem of paper jamming. As a result, the conveyance of the long corrugated cardboard material is stopped, and the entire manufacturing line of the corrugated cardboard box stops.

[0007] Further, when the long corrugated cardboard material is composed of a plurality of short corrugated cardboard materials joined together, the joint of the long corrugated cardboard material may interfere with making slits or ruled lines for manufacturing the corrugated cardboard blank.

[0008] The present invention has been made in view of the above problems, and an object thereof is to provide a technique for preventing the manufacturing line from stopping when pulling out a long corrugated cardboard material from a long corrugated cardboard material stack and supplying it to the manufacturing line of corrugated cardboard blanks. Means for Solving the Problems

[0009] A first aspect of the corrugated sheet supply device according to the present invention made to solve the above problems is as follows. A conveying unit that pulls out the long corrugated material from a stack of long corrugated materials formed by folding a long corrugated material in a bellows shape at creases at predetermined intervals and conveys it along a conveyance path; A long corrugated material cutting unit that cuts the long corrugated material in a direction perpendicular to the conveyance direction while the long corrugated material is being conveyed along the conveyance path; A crease detection means for detecting the presence or absence of a crease in a range of a predetermined first length or less from the tip of the long corrugated material being conveyed along the conveyance path; A control unit that controls the long corrugated material cutting unit to perform sheet cutting to cut the long corrugated material at a position of a predetermined sheet length longer than the first length from the tip, and when the crease detection means detects a predetermined crease, perform crease cutting to cut the long corrugated material at a position of a second length shorter than the sheet length and including the predetermined crease from the tip; It is provided with.

[0010] The corrugated sheet supply device of the first aspect is a device that cuts out a corrugated sheet that becomes the basis of a corrugated blank from a long corrugated material folded in a bellows shape and supplies it to a corrugated blank manufacturing device. In the device with the above configuration, when it is detected that there is a predetermined crease in a range of a predetermined first length or less from the tip of the long corrugated material being conveyed along the conveyance path, the long corrugated material is cut at a second length including the crease from the tip of the long corrugated material. As a result, the state where a predetermined crease exists at the tip portion of the long corrugated material is eliminated, and the tip of the long corrugated material introduced into the corrugated blank manufacturing device is prevented from bending. For this reason, smooth conveyance of the long corrugated material becomes possible. Note that the second length may be shorter or longer than the first length as long as it includes a predetermined crease.

[0011] A second aspect of the corrugated sheet supply device according to the present invention made to solve the above problems is as follows. A conveying unit that pulls out the long corrugated material from a stack of long corrugated materials formed by folding the long corrugated material in a bellows shape at predetermined intervals and conveys it along a conveying path, A long corrugated material cutting unit that cuts the long corrugated material conveyed along the conveying path in a direction perpendicular to the conveying direction, A crease detection means for detecting the presence or absence of a crease in a range between a position of a predetermined sheet length from the tip of the long corrugated material conveyed along the conveying path and a position of a predetermined first length upstream of the position, When the crease detection means detects a predetermined crease, a crease feed sheet cutting is performed to cut the long corrugated material at a position of a third length that is longer than the sheet length and includes the predetermined crease from the tip. When the crease detection means does not detect the predetermined crease, a control unit that controls the long corrugated material cutting unit to perform a sheet cutting to cut the long corrugated material at the position of the sheet length from the tip, Comprising.

[0012] In the corrugated sheet supply device of the second aspect, before cutting the long corrugated material, It is detected whether or not a predetermined crease exists around the cutting position upstream of the cutting position. When it is detected that there is a crease, the long corrugated material is cut from the tip of the long corrugated material at a third length including the crease. As a result, the state in which a predetermined crease exists in the tip portion of the long corrugated material is eliminated, and the tip of the long corrugated material introduced into the corrugated blank manufacturing device is prevented from bending. Therefore, smooth conveyance of the long corrugated material becomes possible. Further, in the above configuration, the crease feed sheet cutting serves both as cutting for cutting out the corrugated sheet and cutting for removing the crease, so that both cutting processes can be completed at once, and the supply efficiency of the corrugated sheet can be improved.

[0013] Preferably, the corrugated sheet supply device The detection means can determine whether the fold line is concave or convex, and can measure the depth when the fold line is concave and the height when the fold line is convex. When the depth of the fold line is greater than a predetermined depth value or the height is greater than a predetermined height value, the control unit controls the long corrugated material cutting unit to perform the fold line cutting.

[0014] In the long corrugated material pulled out from the long corrugated material stack, concave and convex fold lines will alternately appear on the conveying path. According to this configuration, when the depth of the concave fold line and the height of the convex fold line are greater than the respective threshold values (depth value, height value) used for the determination, the fold line cutting is performed, thereby removing the cause of paper jams. When the depth of the concave part is shallow or the height of the convex part is low, the fold line cutting is not performed, so that the long corrugated material to be discarded can be reduced.

[0015] Moreover, a third aspect of the corrugated sheet supply device according to the present invention made to solve the above problems is a conveying unit that conveys a long corrugated material formed by joining the ends of a plurality of short corrugated materials along a conveying path; a long corrugated material cutting unit that cuts the long corrugated material conveyed on the conveying path in a direction orthogonal to the conveying direction; joint detection means for detecting the presence or absence of a joint in the long corrugated material conveyed on the conveying path; a control unit that controls the long corrugated material cutting unit to perform a joint cutting operation for cutting the long corrugated material at a position upstream of the joint by a predetermined distance when the presence of the joint is detected; It is provided with.

[0016] The corrugated sheet feeding device of the third aspect is a device that cuts out a corrugated sheet that serves as the basis for a corrugated blank from a long corrugated material formed by joining a plurality of short corrugated materials and supplies it to a corrugated blank manufacturing device. The short corrugated materials may have any length as long as they are shorter than the long corrugated material. In the above corrugated sheet feeding device, when the long corrugated material being conveyed along the conveyance path has a joint, the long corrugated material is cut in a direction perpendicular to the conveyance direction at a position upstream of the joint by a predetermined distance. As a result, the joint is removed from the long corrugated material. Then, a corrugated sheet of a predetermined length is cut out from the long corrugated material after the joint has been removed and supplied to the corrugated blank manufacturing device. Therefore, when cutting out a corrugated blank from the corrugated sheet, slitting and scoring can be performed smoothly. Also, when assembling a corrugated box from the corrugated blank, the strength and appearance of the box are not impaired.

[0017] In the corrugated sheet feeding devices of the first to third aspects, as the crease detection means or joint detection means, a line sensor including a plurality of image sensors arranged in a row in the width direction of the long corrugated material, or a camera-type laser displacement sensor can be employed. The camera-type laser displacement sensor includes a light projecting unit for laser light and a light receiving unit for receiving the reflected light reflected from the object, and can recognize the presence or absence of a crease or joint from the image acquired by the camera. Further, in the case where the detection means is configured to detect the depth of a concave crease and the height of a convex crease, it is preferable to configure the detection means from a contact sensor, an ultrasonic sensor, or the like.

Advantages of the Invention

[0018] According to the first aspect of the present invention, by removing the creases within a predetermined length range from the tip of the long corrugated material drawn from the stack of long corrugated materials, paper jams are suppressed when introducing the long corrugated material into the cutting section. Further, in the second aspect of the present invention, since the joint is removed from the corrugated sheet for manufacturing the corrugated blank, slitting and scoring can be performed smoothly. In both the first and second aspects, the manufacturing line of the corrugated blank is prevented from stopping.

Brief Description of the Drawings

[0019]

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Embodiments for Carrying Out the Invention

[0020] Hereinafter, embodiments of the present invention will be described with reference to the drawings. It should be noted that the present invention is not limited to the embodiments described below, and it goes without saying that various aspects are included without departing from the spirit of the present invention.

[0021] <First Embodiment> <Device Configuration> FIG. 1 is a diagram schematically showing the configuration of a corrugated blank manufacturing apparatus 100. FIG. 2 is a view of a conveyance path, which is a part of the corrugated blank manufacturing apparatus 100, seen from above. FIG. 3 is a block diagram for explaining the main control system of the corrugated blank manufacturing apparatus 100.

[0022] The corrugated board blank manufacturing apparatus 100 of the present embodiment is an apparatus that cuts out a corrugated board blank 63 of an appropriate length and an appropriate shape from a single long corrugated board material 61. In this embodiment, a material made of double-sided corrugated board is used as the long corrugated board material 61. The long corrugated board material 61 made of double-sided corrugated board is in a state (long corrugated board material stack) 60 that is folded in a bellows shape at predetermined intervals and stacked vertically, and is pulled out and used therefrom.

[0023] The above double-sided corrugated board includes not only a single flute composed of three base papers corresponding to one core and two liners respectively, but also multi-flutes composed of two or more cores, two liners, and one or more middle liners such as "double double-sided corrugated board" and "double double double-sided corrugated board". Also, there are no restrictions on the thickness of the above double-sided corrugated board or the type of core (flute), and it is possible to adopt various types of double-sided corrugated boards (A flute, B flute, C flute, AB flute, AC flute, etc.).

[0024] The corrugated board blank manufacturing apparatus 100 includes a conveying unit 10, a pulling-out unit 20, a first cutting unit 30, and a second cutting unit 40. Further, the corrugated board blank manufacturing apparatus 100 includes a control unit 50 that controls these units. In this embodiment, the conveying unit 10, the first cutting unit 30, and the control unit 50 constitute a corrugated board sheet supply apparatus 200. The corrugated board sheet supply apparatus 200 cuts out a corrugated board sheet 62 of a predetermined length from the long corrugated board material 61 by the first cutting unit 30 and supplies it to the second cutting unit 40.

[0025] <Conveying unit 10> The conveying unit 10 conveys the long corrugated board material 61 pulled out from the long corrugated board material stack 60 by the pulling-out unit 20 along the conveying path 11.

[0026] The conveying unit 10 includes a plurality of conveying rollers 12 arranged in a row with intervals therebetween, and a driving unit 13 (see FIG. 3) that rotates the plurality of conveying rollers 12 synchronously. Each conveying roller 12 is supported in a horizontal posture with its axial direction orthogonal to the arrangement direction. Further, the axial length of each conveying roller 12 is slightly larger than the width of the long corrugated cardboard material 61.

[0027] The driving unit 13 rotates the plurality of conveying rollers 12 based on a command from the control unit 50. When the conveying rollers 12 rotate, the long corrugated cardboard material 61 (and the corrugated cardboard sheets 62 and corrugated cardboard blanks 63 cut out therefrom) placed on these conveying rollers 12 are conveyed. In this embodiment, the conveying path 11 is constituted by the plurality of conveying rollers 12. Above the upstream side of the conveying path 11, a pressing roller 14 is provided to prevent the long corrugated cardboard material 61 from lifting off the upper surface of the conveying path 11. The operation control of the driving unit 13 by the control unit 50 is intermittently executed in consideration of the processing time at the first cutting unit 30 and the second cutting unit 40.

[0028] The conveying path 11 is provided at a predetermined height position from the floor surface, and a waste storage portion 71 is installed below it. The waste storage portion 71 stores the waste generated at the first cutting unit 30 and the second cutting unit 40 described later and falling from the gaps between the plurality of conveying rollers 12.

[0029] In the following description, the direction parallel to the floor surface along the conveying path 11 is the X direction, the direction parallel to the floor surface and orthogonal to the conveying direction of the conveying path 11 is the Y direction, and the direction perpendicular to the floor surface is the Z direction (see FIGS. 1 and 2). When the floor surface is a horizontal plane, the X direction and the Y direction are horizontal directions, and the Z direction is a vertical direction.

[0030] <Drawer unit 20> The drawer unit 20 pulls out the long corrugated cardboard material 61 from the long corrugated cardboard material stack 60 arranged on the floor surface and conveys it into the conveying unit 10, and includes a rotating body 21 and a support frame 22 that rotatably supports the rotating body 21 about its rotation axis 23.

[0031] The rotating body 21 is composed of a triangular cylindrical body with a regular triangular cross-section, and a rotating shaft 23 is provided at the axial center of the triangular cylindrical body. The length of one side of the triangle in the cross-section of the triangular cylindrical body corresponds to the pitch of the fold provided on the long corrugated cardboard material 61, and the axial length of the triangular cylindrical body is configured to be slightly longer than the width of the long corrugated cardboard material 61. The rotating body 21 is supported by the support frame 22 in a posture where the rotating shaft 23 is in the Y direction and the rotating body 21 is positioned above the upper surface of the long corrugated cardboard material stack 60.

[0032] In the drawer part 20 with the above configuration, a long corrugated cardboard material 61 of a predetermined length is pulled out from the long corrugated cardboard material stack 60, and the portion between the folds (for one pitch) is aligned with one side surface of the rotating body 21. Then, the leading end of the long corrugated cardboard material 61 is further pulled out to the position where the pressing roller 14 on the conveying path 11 is provided. When the conveying roller 12 is rotated in this state and the long corrugated cardboard material 61 is conveyed along the conveying path 11, the rotating body 21 rotates, and the long corrugated cardboard material 61 is pulled out from the long corrugated cardboard material stack 60 by one pitch at a time.

[0033] A rotation sensor 24 (see FIG. 3) for detecting the rotation state of the rotating body 21 is attached to the rotating shaft 23 of the rotating body 21. The rotation sensor 24 is connected to the control unit 50, and the detection result is input to the control unit 50. The control unit 50 monitors the feeding status of the long corrugated cardboard material 61 using the detection result of the rotation sensor 24.

[0034] <First cutting part 30> The first cutting part 30 is arranged in the middle of the conveying path 11 and cuts the long corrugated cardboard material 61 into a predetermined length to cut out the corrugated cardboard sheet 62. Also, the first cutting part 30 detects the presence or absence of folds that cause paper jams within a range from the leading end of the long corrugated cardboard material 61 conveyed on the conveying path 11, including the leading end, to a length in the predetermined X direction (corresponding to the first length of the present invention) or less, by a sensor 33 as a fold detection means. If such a fold is present, it is removed. Hereinafter, the above range is referred to as the "first fold detection range".

[0035] The first cutting part 30 includes a cutting blade 31, a lifting mechanism 32 for lifting the cutting blade 31, and a sensor 33. The cutting blade 31 is supported such that the direction of its blade is along the Y direction. The length of the cutting blade 31 in the Y direction is slightly larger than the width of the long corrugated cardboard material 61. The lifting mechanism 32 is electrically connected to the control unit 50 and lifts the cutting blade 31 according to a command from the control unit 50. The first cutting part 30 corresponds to the long corrugated cardboard material cutting part in the present invention that cuts the long corrugated cardboard material 61 in a direction perpendicular to the conveying direction.

[0036] The sensor 33 is arranged on the upstream side of the cutting blade 31. In the long corrugated cardboard material 61 pulled out from the long corrugated cardboard material stack 60, concave folds and convex folds when folded in a bellows shape appear alternately. The sensor 33 detects whether there is a fold in the first fold detection range including the tip of the long corrugated cardboard material 61. The sensor 33 is electrically connected to the control unit 50 and outputs its detection signal to the control unit 50.

[0037] The sensor 33 is composed of, for example, a camera-type laser displacement sensor, and includes a laser emitting part, a MEMS (Micro Electro Mechanical Systems) mirror for adjusting the traveling direction of the laser light emitted from the laser emitting part, an illumination part, and a CMOS camera. This camera-type laser displacement sensor corrects the irradiation position of the laser light using the image acquired by the CMOS camera, scans a predetermined area while changing the traveling direction of the laser light with the MEMS mirror, and acquires depth information and height information within that area. In the present embodiment, the sensor 33 is arranged such that at least a part of the first fold detection range including the tip of the long corrugated cardboard material 61 is included in the predetermined area (hereinafter referred to as the scan area). Therefore, the detection result of this sensor 33 includes not only the presence or absence of a fold, but also information on whether the shape of the fold is concave or convex, and the depth value or height value of the concavity and convexity.

[0038] On the downstream side of the first cutting portion 30, guide members 15 and 16 are provided for guiding the corrugated sheet 62 while pressing down on its fold line.

[0039] The control unit 50 executes "sheet cutting" in which the cutting blade 31 is lowered to cut the long corrugated material 61 and a corrugated sheet 62 of a predetermined length (hereinafter referred to as "sheet length") is cut out. Further, when the sensor 33 scans the scan area and detects a fold line to be excluded in the scan area, the conveying unit 10 is controlled to convey the long corrugated material 61 by a predetermined length, and at a position upstream of the fold line, the cutting blade 31 is lowered to execute "fold line cutting" for cutting. The predetermined length for conveying the long corrugated material 61 corresponds to the second length of the present invention and is set to a value longer than the X-direction length of the scan area. Thereby, a range including the fold line is cut off from the tip of the long corrugated material 61. If the second length is set to a value shorter than the sheet length and longer than the X-direction length of the scan area, the long corrugated material is not wasted. Hereinafter, the length (second length) from the tip of the long corrugated material 61 to the position where the fold line cutting is executed is referred to as "cutting length". Note that the sheet length, which is the length of the corrugated sheet 62, may be a constant value or may be variable according to an external instruction. For example, when manufacturing a corrugated blank 63 for a box for packing goods of always the same shape, the sheet length is a constant value. On the other hand, when manufacturing a corrugated blank 63 for a box for packing goods of various shapes, the sheet length is set to a value suitable for the shape of each product. In this case, the sheet length may be input by an operator, or a 3D measuring device for measuring the shape of each product may be provided, and a size suitable for each product may be calculated and obtained from the measurement result of the device.

[0040] <Second cutting portion 40> The second cutting portion 40 is provided on the downstream side of the first cutting portion 30 in the middle of the conveyance path 11, cuts out the corrugated blank 63 from the corrugated sheet 62 conveyed on the conveyance path 11, and performs ruled line application and / or grooving.

[0041] The second cutting part 40 is configured to include a cutting blade 41 and a drive mechanism 42 for moving the cutting blade 41. The drive mechanism 42 includes, for example, a rotational drive mechanism for rotating the cutting blade 41 around the Z axis, an X-direction drive mechanism for moving the cutting blade 41 in the X direction, and a lifting drive mechanism for lifting the cutting blade 41. The drive mechanism 42 is electrically connected to the control unit 50 and moves the cutting blade 41 according to a command from the control unit 50.

[0042] The second cutting part 40 further includes a pressing blade 43 and a drive mechanism 44 for moving the pressing blade 43. The drive mechanism 44 includes, for example, a rotational drive mechanism for rotating the pressing blade 43 around the Z axis, an X-direction drive mechanism for moving the pressing blade 43 in the X direction, and a lifting drive mechanism for lifting the pressing blade 43. The drive mechanism 44 is electrically connected to the control unit 50 and moves the pressing blade 43 according to a command from the control unit 50.

[0043] <Control unit 50> The control unit 50 includes an arithmetic unit and a memory, and controls the operation of the entire corrugated board blank manufacturing apparatus 100. A control panel 51 composed of a liquid crystal display device equipped with a touch panel is connected to the control unit 50 to receive various inputs from the user.

[0044] <Score cutting process in the first cutting part> The score cutting process in the first cutting part 30 will be described with reference to FIGS. 4 and 5. In FIG. 4, the interval of the score lines 611 (shown by the broken line in the figure) of the long corrugated board material 61 is represented as P, the length in the X direction of the first score detection range 613a is represented as D1, the cutting length is represented as D2, and the sheet length of the corrugated board sheet 62 is represented as D3. The lengths D1, D2, and D3 have the relationship of D1 < D2 < D3. Also, in FIG. 4, the rectangular area 330 indicated by the dashed line is the scan area of the sensor 33, and the thick arrow indicates the cutting position by the cutting blade 31.

[0045] In this embodiment, the length of the scanning region 330 of the sensor 33 in the X direction is slightly larger than the length of the first fold detection range 613a in the X direction, and the length of the scanning region 330 in the Y direction is smaller than the length of the first fold detection range 613a in the Y direction. The sensor 33 detects the presence or absence of the fold 611 within this scanning region 330 and sends the detection result to the control unit 50. Since the fold exists across the entire width direction of the long corrugated material 61, even if the length of the scanning region 330 in the Y direction is smaller than the length of the first fold detection range 613a in the Y direction, the presence or absence of the fold within the first fold detection range 613a can be detected. The detection result includes information on the presence or absence of the fold, the shape of the fold, and the depth value or height value of the fold.

[0046] When the corrugated sheet 62 is cut out from the long corrugated material 61, the control unit 50 executes the fold cutting process according to the flowchart shown in FIG. 5. That is, the control unit 50 acquires the detection result from the sensor 33 (step 301), and determines the presence or absence of the fold within the scanning region 330 from the result (step 302). Then, when it is determined that there is no fold within the scanning region 330 (No in step 302), the control unit 50 conveys the long corrugated material 61 by the sheet length D3 (step 308), and then lowers the cutting blade 31 to cut out the corrugated sheet 62 (step 309).

[0047] When it is determined that there is a crease within the scan area 330 (Yes in step 302), next, the shape of the crease is determined. If the shape of the crease is concave (Yes in step 303), its depth value is compared with threshold B. The depth value refers to the distance from the upper surface of the portion of the long corrugated material 61 without a crease to the deepest part of the concave crease. If the depth value is less than or equal to threshold B (No in step 305), the control unit 50 conveys the long corrugated material 61 by a sheet length D3 (step 308) and lowers the cutting blade 31 (step 309). Thereby, a corrugated sheet 62 with a sheet length D3 is cut out. On the other hand, if the depth value of the concave crease is greater than threshold B (Yes in step 305), the control unit 50 conveys the long corrugated material 61 by a cutting length D2 (step 306) and lowers the cutting blade 31 (step 307). Thereby, a range of a cutting length D2 is cut off from the tip of the long corrugated material 61. Thereafter, the control unit 50 returns to step 301. When it is confirmed from the detection result of the sensor 33 that the crease has been removed (No in step 302), the long corrugated material 61 is conveyed by a sheet length D3 (step 308). Then, the cutting blade 31 is lowered to cut the long corrugated material 61 (step 309), and a corrugated sheet 62 with a sheet length D3 is cut out.

[0048] In the determination of the shape of the fold line in step 303, when it is determined that the shape of the fold line is not concave (that is, the shape of the fold line is convex) (No in step 303), the height value of the fold line is compared with the threshold value A. The height value of the fold line refers to the distance from the upper surface of the portion without the fold line in the long corrugated cardboard material 61 to the top of the convex fold line. If the height value is less than or equal to the threshold value A (No in step 304), the control unit 50 conveys the long corrugated cardboard material 61 by the sheet length D3 (step 308) and lowers the cutting blade 31 (step 309). Thereby, the corrugated cardboard sheet 62 with the sheet length D3 is cut out. On the other hand, when the height value of the convex fold line is greater than the threshold value A (Yes in step 304), the control unit 50 conveys the long corrugated cardboard material 61 by the cutting length D2 (step 306) and lowers the cutting blade 31 (step 307). Thereby, the range of the cutting length D2 is cut off from the tip of the long corrugated cardboard material 61. Thereafter, the control unit 50 returns to step 301, confirms that the fold line has been removed (No in step 302), conveys the long corrugated cardboard material 61 (step 308), lowers the cutting blade 31 (step 309), and cuts out the corrugated cardboard sheet 62 with the sheet length D3.

[0049] The corrugated cardboard sheet 62 with the sheet length D3 cut out by the above fold line cutting process is carried into the second cutting unit 40, and the corrugated cardboard blank 63 is cut out. At this time, since a predetermined fold line is removed from the corrugated cardboard sheet 62, paper jams are avoided in the second cutting unit 40.

[0050] The above-mentioned threshold value A and threshold value B are appropriately set in consideration of the material of the long corrugated cardboard material 61 and the occurrence status of past paper jams. For example, the threshold value A and threshold value B are set to values from 0.1 times to 0.7 times the thickness of the long corrugated cardboard material 61, preferably values from 0.2 times to 0.6 times, and more preferably values from 0.3 times to 0.5 times. The threshold value A and the threshold value B may be the same value or different values. By appropriately setting the threshold value A and the threshold value B, only when there is a fold near the tip of the long corrugated cardboard material 61 and the unevenness of the fold is large, the range of length D2 from the tip of the long corrugated cardboard material 61 is cut off. Therefore, while avoiding paper jams, the amount of the long corrugated cardboard material 61 that is unnecessarily discarded can be reduced.

[0051] Furthermore, it is advisable to set the above-mentioned threshold value A and threshold value B in consideration of the folding strength of the fold of the long corrugated cardboard material 61. By doing so, the amount of the long corrugated cardboard material 61 that is unnecessarily discarded can be further reduced. For example, when the folding strength of the fold is 400 [mN] or less, the threshold value A and threshold value B are set to values from 0.1 times to 0.7 times the thickness of the long corrugated cardboard material 61, and when it exceeds 400 [mN], they are set to values from 0.3 times to 0.5 times. The threshold value A and the threshold value B may be the same value or different values. Note that the folding strength of the fold can be measured based on the corrugated cardboard industry standard T001:2000.

[0052] In this embodiment, the cutting length D2 is made longer than the X-direction length D1 of the first fold detection range 613a, but they may be the same length. Also, the cutting length D2 may be a constant length, or may be changed according to the position of the fold. When the X-direction length D1 of the first fold detection range 613a is 20 mm, the cutting length D2 is preferably about 20 mm to 40 mm. Also, in a configuration where the cutting length D2 is changed according to the position of the fold, when the fold is located at a length D4 from the tip of the long corrugated cardboard material 61, the length D2 can be set to a length about 5 mm to 20 mm larger than the length D4.

[0053] In the first embodiment, the control unit 50 detects the presence or absence of a fold line and the shape of the fold line, and performs fold line cutting only when the depth value and height value of the fold line are equal to or greater than a predetermined value. However, it may be configured to determine only the presence or absence of a fold line, and to always perform fold line cutting when it is determined that a fold line is present. Further, when there is a difference in the frequency of paper jams at the second cutting unit 40 depending on the shape of the fold line, the control unit 50 may be configured to perform fold line cutting only when the shape of the fold line is either concave or convex.

[0054] <Second Embodiment> The corrugated board blank manufacturing apparatus according to the second embodiment is different from the corrugated board blank manufacturing apparatus according to the first embodiment in that it is configured to execute a joint cutting process instead of a fold line cutting process. Since the other configurations are substantially the same as those of the corrugated board blank manufacturing apparatus 100 of the first embodiment, the same reference numerals are given to the same parts as those of the corrugated board blank manufacturing apparatus 100 of the first embodiment for explanation.

[0055] The long corrugated board material 61 used in the corrugated board blank manufacturing apparatus of the present embodiment is constituted by joining a plurality of short corrugated board materials shorter than it, and the joint cutting process refers to a process of removing the joint portion between the short corrugated board materials from the long corrugated board material 61.

[0056] <Joint portion> First, an example of a joint portion removed from the long corrugated board material 61 will be described. Here, the two short corrugated board materials constituting one joint portion 612 are referred to as a first short corrugated board material 614 and a second short corrugated board material 615.

[0057] Figures 6A and 6B show an example of a joint portion 612 formed by compressing one end portion (rear end portion) of the first short cardboard material 614 and the other end portion (front end portion) of the second short cardboard material 615 so that the entire width direction becomes about half of the original thickness, and applying an adhesive to one side of these compressed portions and bonding them. In this example, the end portions of the first and second short cardboard materials 614 and 615 are joined so that the thickness at the joint portion 612 of the long cardboard material 61 becomes substantially the same as the thickness of the other portions. Although the long cardboard material 61 configured in this way has substantially the same overall thickness, a concave groove portion 701 is formed on the upper surface of the joint portion 612 between the front end of the second short cardboard material 615 and the vicinity of the rear end of the first short cardboard material 614, and a concave groove portion 702 is formed on the lower surface of the joint portion 612 between the rear end of the first short cardboard material 614 and the vicinity of the front end of the second short cardboard material 615.

[0058] Figures 7A and 7B show an example of a joint portion 612 formed by applying an adhesive to the lower surface of the rear end portion of the first short cardboard material 614 and the upper surface of the front end portion of the second short cardboard material 615 and then crushing the bonded portion with pressing members 201 and 202. The pressing members 201 and 202 have a length substantially the same as the width of the first and second short cardboard materials 614 and 615, and have two protruding ridge portions 211 extending in the longitudinal direction thereof and a groove portion 212 therebetween. The two pressing members 201 and 202 crush the portion where the end portions of the two short cardboard materials 614 and 615 are bonded together such that one protruding ridge portion 211 of these fits into the other groove portion 212. Two parallel pressing lines 711 and 712 are formed on the upper surface of the joint portion 612 of the long cardboard material 61 configured in this way, and two parallel pressing lines 713 and 714 are formed on the lower surface.

[0059] The joint 612 shown in Fig. 8A is formed by bonding the rear end portion of the first short-length corrugated material 614 and the front end portion of the second short-length corrugated material 615 as shown in Fig. 8B. The first short-length corrugated material 614 is composed of one corrugated sheet 6141 and two liners 6142 and 6143. At the rear end portion of the first short-length corrugated material 614, the lower liner 6143 protrudes rearward by a length L1 (that is, the corrugated sheet 6141 and the upper liner 6142 are not provided at the rear end portion of the first short-length corrugated material 614). On the other hand, the second short-length corrugated material 615 is composed of one corrugated sheet 6151 and two liners 6152 and 6153. At the front end portion of the second short-length corrugated material 615, the upper liner 6152 protrudes forward by a length L2, and the corrugated sheet 6151 protrudes forward by a length slightly shorter than L2 (that is, the lower liner 6153 is not provided at the front end portion of the second short-length corrugated material 615, and the upper liner 6152 protrudes slightly forward of the corrugated sheet 6151).

[0060] The long-length corrugated material 61 is formed by applying an adhesive to the upper surface of the lower liner 6143 at the rear end portion of the first short-length corrugated material 614 having the above configuration and the lower surface of the upper liner 6152 that protrudes forward of the corrugated sheet 6151 at the front end portion of the second short-length corrugated material 615, and then bonding the two together. At this time, the rear end of the lower liner 6143 of the first short-length corrugated material 614 is bonded to overlap the front end of the lower liner 6153 of the second short-length corrugated material 615, and the front end of the upper liner 6152 of the second short-length corrugated material 615 is bonded to overlap the rear end of the upper liner 6142 of the first short-length corrugated material 614. Therefore, overlapping portions 6144 and 6154 where two liners overlap are formed on the upper surface and the lower surface of the joint 612, respectively.

[0061] As shown in FIG. 9A, the joint portion 612 is formed by butting the rear end portion of the first short corrugated material 614 and the front end portion of the second short corrugated material 615 as shown in FIG. 9B, and attaching adhesive tapes 165 and 166 to the upper and lower surfaces thereof so as to straddle the butted portion to form the long corrugated material 61. In this example, short corrugated materials of a general shape are used as the first and second short corrugated materials 614 and 615.

[0062] As shown in FIGS. 6A, 7A, 8A, and 9A, the long corrugated material 61 formed by joining the ends of the two short corrugated materials 614 and 615 has concave ridges 701 and 702 (FIG. 6A), ruled lines 711 to 714 (FIG. 7A), overlapping portions 6144 and 6154 (FIG. 8A), and adhesive tapes 165 and 166 (FIG. 9A) as features indicating the joint portion 612. Therefore, in the corrugated board blank manufacturing apparatus 100 of the present embodiment, the sensor 33 is used as a joint portion detection means to detect whether any of these features exist in the long corrugated material 61. When it is detected that the feature exists, the control unit 50 lowers the cutting blade 31 at a position upstream of the feature and performs "joint portion cutting" excluding the tip portion of the long corrugated material 61 including the feature. Hereinafter, the joint portion cutting process will be described.

[0063] <Joint Portion Cutting Process> FIG. 10 shows the scan area 330 of the sensor 33 in the long corrugated material 61, the sheet length D3 of the corrugated board sheet 62, the cutting line 622 for cutting out the corrugated board sheet 62, the joint portion 612, and the cutting line 621 for excluding the joint portion 612. Also, let the length of the scan area 330 in the X direction be D5 (D5 < D3). Note that the scan area 330 of the sensor 33 in the joint portion cutting process will be described as the same as the scan area 330 in the crease cutting process, but it may be different.

[0064] In the flowchart shown in FIG. 11, the control unit 50 acquires a detection result from the sensor 33 (step 401), and determines whether or not there is a portion indicating the feature of the joint portion 612 in the scan area 330 from the result (step 402). For example, in the case of the joint portion 612 shown in FIGS. 6A and 7A, the presence or absence of the joint portion 612 can be determined from the information regarding the depth value. Also, in the case of the joint portion 612 shown in FIGS. 8A and 9A, the presence or absence of the joint portion 612 can be determined from the intensity of the reflected light included in the image information of the camera provided in the sensor 33. That is, since the intensity of the reflected light of the laser light in the overlapping portion 6154 and the adhesive tape 165 is different from the intensity of the reflected light in other locations, when a portion where the reflected light intensity is different is included in the scan area 330, it can be determined that the joint portion 612 is present.

[0065] In step 402, when it is determined that the joint portion 612 is present in the scan area 330 from the detection result of the sensor 33 (Yes), the control unit 50 conveys the long corrugated cardboard material 61 by a length D5 (step 403), and then lowers the cutting blade 31 (step 404). Thereby, the area including the joint portion 612 is cut. Thereafter, the control unit 50 conveys the long corrugated cardboard material 61 by the sheet length D3 (step 405), and lowers the cutting blade 31 to cut out the corrugated cardboard sheet 62 (step 410).

[0066] In step 402, if it is determined that the joint 612 does not exist in the scan area 330 (No), the control unit 50 conveys the long corrugated material 61 by a length D5' (step 406), and increases the detection count N of the joint 612 by 1 (step 407). Then, if the product of the length D5' and the detection count N (D5'×N) is shorter than the sheet length D3 (No in step 408), the process returns to step 401, and again, the presence or absence of the features of the joint 612 is detected. On the other hand, if the product of the length D5' and the detection count N (D5'×N) is longer than the sheet length D3 (Yes in step 408), the drive unit 13 is controlled to rotate the conveying roller 12 in the forward or reverse direction so that the position where the length from the tip of the long corrugated material 61 becomes D3 comes to the cutting position of the first cutting unit 30. After adjustment (step 409), the cutting blade 31 is lowered to cut out the corrugated sheet 62 (step 410).

[0067] In FIG. 10, as a result of performing the detection operation of the presence or absence of the joint 612 in the scan area 330 three times (N = 3), it is detected that the joint 612 exists, and the cutting line 621 when the cutting process (steps 403 and 404) for removing the joint 612 is executed, and the state where the position of the cutting line 622 for cutting out the corrugated sheet 62 is changed as a result of cutting the long corrugated material 61 with the cutting line 621 is shown. The position of the cutting line 622 after the change is a position upstream by the sheet length D3 from the cutting line 621. As shown in FIG. 10, by executing the joint cutting process and changing the position of the cutting line 622, the corrugated sheet 62 without the joint 612 can be cut out from the long corrugated material 61.

[0068] Note that if it is known in advance that the interval between the joints 612 appearing in the long corrugated material 61 is very large compared to the sheet length D3 of the corrugated sheet, after the joint cutting process is executed once, the same process may not be executed for some time.

[0069] In addition, in this embodiment, the presence or absence of the features of the joint portion 612 is determined using the detection result of the sensor 33. However, a sensor different from the sensor 33, for example, a line sensor including a plurality of imaging elements (for example, CCD imaging sensor elements or CMOS imaging elements) arranged in a line in the width direction of the long corrugated material 61, may be used as the joint portion detection means.

[0070] Furthermore, although the corrugated cardboard blank manufacturing apparatus of this embodiment is configured to execute only the cutting process of the joint portion, it may be configured to execute both the crease cutting process and the joint portion cutting process.

[0071] <Third Embodiment> The corrugated cardboard blank manufacturing apparatus according to the third embodiment has substantially the same configuration as the corrugated cardboard blank manufacturing apparatus according to the first embodiment. However, the range in which the crease detection means detects the presence or absence of a crease, and the processing after detecting the presence of a crease are different from those of the corrugated cardboard blank manufacturing apparatus according to the first embodiment. Therefore, the same reference numerals are given to the same parts as those of the corrugated cardboard blank manufacturing apparatus 100 of the first embodiment, and the description of the configuration of the corrugated cardboard blank manufacturing apparatus according to this embodiment is omitted.

[0072] The cutting process in the first cutting portion 30 of this embodiment will be described with reference to FIGS. 12A to C and FIGS. 13A and B.

[0073] FIG. 12A is a diagram showing a range in which a crease detection means detects a crease in the long cardboard material 61. In the present embodiment, the crease detection means (sensor 33) detects the presence or absence of a crease in a range between a position of a predetermined sheet length (sheet length) from the tip of the long cardboard material 61 conveyed on the conveyance path 11 and a position of a predetermined length in the X direction (corresponding to the first length of the present invention) upstream of that position. Hereinafter, the said range is called "second crease detection range". In FIG. 12A, the rectangular area indicated by the dashed line is the scan area 330 of the sensor 33, the rectangular area indicated by the two-dot chain line is the second crease detection range 613b, and the thick arrow indicates the cutting position by the cutting blade 31. Also, P is the interval between the creases 611 of the long cardboard material 61, D1 is the length in the X direction (first length) of the second crease detection range 613b, and D3 is the sheet length. In the present embodiment, the sensor 33 performs scanning in a region including the cutting position upstream of the cutting position by the cutting blade 31. Therefore, the position of the long cardboard material 61 is adjusted so that the range in the X direction of the second crease detection range 613b is included in the scan area 330.

[0074] When the sensor 33 detects that there is a crease in the second crease detection range, the control unit 50 controls the drive unit 13 of the conveyance unit 10 to convey the long cardboard material 61 downstream by a predetermined length (hereinafter referred to as "feed length"). In FIG. 12A, D6 indicates the feed length. The feed length is set to a value shorter than the sheet length D3 and longer than the length in the X direction of the scan area 330 (the length D1 in the X direction of the second crease detection range 613b). That is, the lengths D1, D3, and D6 have the relationship of D1 < D6 < D3.

[0075] FIG. 12B shows a state in which the long corrugated material 61 is conveyed downstream by a feed length D6 from the state of FIG. 12A. After reaching such a state, the control unit 50 lowers the cutting blade 31 at a position having a length (corresponding to the third length of the present invention) that is greater than the sheet length D3 by the feed length D6 from the tip of the long corrugated material 61, and executes "folding feed sheet cutting" to cut out the corrugated sheet 62a from the long corrugated material 61. In FIG. 12B, the dashed-dotted line is the cutting line 623 for cutting out the corrugated sheet 62a, and D7 indicates the length (third length) of the corrugated sheet 62a cut out by the folding feed sheet cutting. When the folding feed sheet cutting is executed, as shown in FIG. 12C, a corrugated sheet 62a having a length in the X direction that is greater than the sheet length D3 by the feed length D6 is cut out.

[0076] On the other hand, as shown in FIG. 13A, when the sensor 33 does not detect a crease in the second crease detection range, the control unit 50 lowers the cutting blade 31 at a position of a predetermined sheet length (sheet length) from the tip of the long corrugated material 61, and executes "sheet cutting" to cut out the corrugated sheet 62b. FIG. 13B shows a state in which the corrugated sheet 62b having a sheet length D3 is cut out.

[0077] As described above, in the present embodiment, before cutting the long corrugated material 61, it is detected whether there is a crease around the cutting position on the upstream side of the cutting position. If it is detected that there is a crease, the long corrugated material 61 is cut at a position upstream of the crease. By doing so, a corrugated sheet having a crease in the rear end portion is cut out, and the tip portion of the long corrugated material 61 that is subsequently fed is in a state without a crease.

[0078] Next, regarding the specific process, it will be described with reference to the flowchart shown in FIG. 14. When the long corrugated material 61 is cut, the control unit 50 conveys the long corrugated material 61 by the sheet length D3 (step 501), and obtains the detection result from the sensor 33 (step 502). From the result, it determines the presence or absence of a fold line within the scan area 330 (step 503). And when it is determined that there is no fold line within the scan area 330 (No in step 503), the control unit 50 lowers the cutting blade 31 to cut out the corrugated sheet 62b with the sheet length D3 (step 509). After that, the control unit 50 returns to step 501 and repeats the subsequent steps.

[0079] When it is determined that there is a fold line within the scan area 330 (Yes in step 503), next, the shape of the fold line is determined. If the shape of the fold line is concave (Yes in step 504), its depth value is compared with the threshold B. The depth value refers to the distance from the upper surface of the portion without a fold line in the long corrugated material 61 to the deepest part of the concave fold line. If the depth value is less than or equal to the threshold B (No in step 506), the control unit 50 lowers the cutting blade 31 (step 509). Thereby, the corrugated sheet 62b with the sheet length D3 is cut out. On the other hand, if the depth value of the concave fold line is greater than the threshold B (Yes in step 506), the control unit 50 conveys the long corrugated material 61 by the feed length D6 (step 507), and lowers the cutting blade 31 (step 508). Thereby, the corrugated sheet 62a with the length D7 (D3 + D6) as the length in the X direction is cut out. After that, the control unit 50 returns to step 501 and repeats the subsequent steps.

[0080] In the determination of the shape of the fold line in step 504, when it is determined that the shape of the fold line is not concave (that is, the shape of the fold line is convex) (No in step 504), the height value of the fold line is compared with the threshold value A. The height value of the fold line refers to the distance from the upper surface of the portion without the fold line in the long corrugated cardboard material 61 to the top of the convex fold line. If the height value is equal to or less than the threshold value A (No in step 505), the control unit 50 lowers the cutting blade 31 (step 509). Thereby, the corrugated cardboard sheet 62b with the sheet length D3 is cut out. On the other hand, when the height value of the convex fold line is greater than the threshold value A (Yes in step 505), the control unit 50 conveys the long corrugated cardboard material 61 by a feed length D6 (step 507) and lowers the cutting blade 31 (step 508). Thereby, the corrugated cardboard sheet 62a with the length D7 (D3 + D6) as the length in the X direction is cut out. Thereafter, the control unit 50 returns to step 501 and repeats the subsequent steps.

[0081] According to the above cutting process, since there is no fold line at the tip portion of the long corrugated cardboard material 61, it is possible to prevent the long corrugated cardboard material 61 from colliding with the guide members 15 and 16 provided on the downstream side of the first cutting unit 30 and the tip from being bent. Further, since the fold line feed sheet cutting (step 508) serves both as cutting for cutting out the corrugated cardboard sheet and cutting for removing the fold line, the cutting processes for both can be completed at once, and the corrugated cardboard sheet can be supplied efficiently.

[0082] The corrugated sheet 62a with length D7 and the corrugated sheet 62b with sheet length D3 cut out by the above cutting process are carried into the second cutting part 40, and a corrugated blank 63 is cut out. The corrugated blank 63 is provided with a margin and a lid part (flap) for manufacturing a corrugated box, and such parts will not affect the dimensions of the corrugated box even if the length is changed slightly. Therefore, in this embodiment, the sizes of a plurality of corrugated blanks, which only differ in the length (X-direction length) of the margin and the lid part located on the upstream side and / or the downstream side in the X direction and the sizes of other parts are the same, are stored in a storage part (not shown) of the control part 50. When the corrugated sheet is carried into the second cutting part 40, the control part 50 reads out the size of the corrugated blank corresponding to the lengths of the corrugated sheets 62a and 62b and cuts out the corrugated blank from the corrugated sheet.

[0083] Therefore, even for corrugated sheets with different sheet lengths, the corrugated boxes assembled and manufactured from the corrugated blanks cut out therefrom will have the same dimensions. As a result, in the first embodiment, the part that was discarded by crease cutting is utilized as the corrugated blank 63, and the amount of corrugated material to be discarded can be reduced.

[0084] Note that the corrugated blank 63 cut out from the corrugated sheet 62a with length D7 may have the same size as that cut out from the corrugated sheet 62b with sheet length D3. In this case, compared with the first embodiment, there is no change in the amount of corrugated material to be discarded, but the rear end part including the crease of the corrugated sheet and the cut end part generated when cutting out the corrugated blank from the corrugated sheet can be discarded together, and the corrugated material to be discarded does not need to be scattered over a wide area.

[0085] Also, in this embodiment, when a fold is detected, the feed length D6 for conveying the long corrugated cardboard material 61 is made longer than the X-direction length D1 of the second fold detection range 613b, but they may be the same length. Also, the feed length D6 may be a constant length, or may be changed according to the position of the fold. When the X-direction length D1 of the second fold detection range 613b is 20 mm, the feed length D6 is preferably about 20 mm to 40 mm. Further, in a configuration where the feed length D6 is changed according to the position of the fold, when the fold is located at a length D4 from the tip of the long corrugated cardboard material 61, the feed length D6 can be set to a length about 5 mm to 20 mm larger than the length D4.

Explanation of Signs

[0086] 100…Corrugated cardboard blank manufacturing apparatus 200…Corrugated cardboard sheet feeding apparatus 10…Conveying section 11…Conveying path 12…Conveying roller 13…Drive section 14…Roller 15…Guide member 16…Guide member 20…Pull-out section 21…Rotating body 22…Support frame 23…Rotating shaft 24…Rotation sensor 30…First cutting section 31…Cutting blade 32…Lifting mechanism 33…Sensor 40…Second cutting section 41…Cutting blade 42…Drive mechanism 43…Pressing blade 44…Drive mechanism 50…Control section 51…Control panel 60…Stack of long corrugated cardboard materials 61…Long corrugated cardboard material 62…Corrugated cardboard sheet 62a…Corrugated cardboard sheet 62b…Corrugated cardboard sheet 63... corrugated board blank 71... scrap storage part 165... adhesive tape 166... adhesive tape 611... fold line 612... joint part 614... first short-length corrugated board material 615... second short-length corrugated board material

Claims

1. A conveying section that pulls out a long-length cardboard material from a long-length cardboard material stack formed by folding the long-length cardboard material into an accordion-like shape with creases at predetermined intervals, and conveys the long-length cardboard material along a conveying path; A long cardboard material cutting unit that cuts the long cardboard material conveyed along the conveying path in a direction perpendicular to the conveying direction; a fold detection means for detecting the presence or absence of the fold in a range between a position of a predetermined sheet length from the leading end of the long cardboard material conveyed along the conveying path and a position of a predetermined first length upstream of the position; a control unit that controls the long cardboard material cutting unit so that, when the crease detection means detects a predetermined crease, a crease feed sheet cutting is performed to cut the long cardboard material at a third length position from the leading edge that is longer than the sheet length and includes the predetermined crease, and when the crease detection means does not detect the predetermined crease, a sheet cutting is performed to cut the long cardboard material at a position from the leading edge to the sheet length; A cardboard sheet supplying device comprising:

2. 2. The cardboard sheet supply device according to claim 1, the fold detection means is capable of determining whether the fold is concave or convex, and is capable of measuring the depth of the fold when the fold is concave, and the height of the fold when the fold is convex, The control unit, when the fold detection means detects a predetermined fold, performs the sheet cutting if the depth of the fold is equal to or less than a predetermined depth value or the height of the fold is equal to or less than a predetermined height value, and performs the fold-feed sheet cutting if the depth of the fold is greater than the depth value or the height of the fold is greater than the height value.

Images