Corrugated cardboard sheet feeding device

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 technology for manufacturing corrugated cardboard blanks of appropriate length and shape from a long corrugated cardboard material.

Background Art

[0002] Conventionally, at work sites where articles are packed in corrugated cardboard, a large number of folded corrugated cardboard boxes are prepared in advance. Workers repeatedly perform the work of unfolding the boxes, assembling them into containers, putting the articles to be packed and, if necessary, cushioning materials into the boxes, and sealing them with tape. When articles to be packed of different sizes and shapes are mixed, multiple types of folded corrugated cardboard boxes of different sizes are prepared, and workers select a box according to the size of the article to be packed.

[0003] Folded corrugated cardboard boxes are manufactured by cutting a developed shape of corrugated cardboard of a target size (a corrugated cardboard blank) from a fixed-size rectangular plate-shaped corrugated cardboard sheet, performing processing such as scoring and grooving, and then fixing the joint margin with adhesive or a stapler. However, when it is desired to manufacture corrugated cardboard boxes of different sizes, if the developed shapes of corrugated cardboard boxes of various sizes are cut from a fixed-size corrugated cardboard sheet, the fixed-size corrugated cardboard sheet must have a size corresponding to the largest developed shape, which in many cases results in significant waste in cutting.

[0004] Accordingly, an apparatus has been proposed in which a long corrugated cardboard material is manufactured in advance, folded in a bellows shape and stacked vertically (this stacked long corrugated cardboard material is referred to as a long corrugated cardboard material stack), when needed, a long corrugated cardboard material of a required length (a length corresponding to the developed shape of the corrugated cardboard box to be manufactured) is pulled out from the stack to cut out a corrugated cardboard blank, a corrugated cardboard box is manufactured from the cut-out corrugated cardboard blank, and products are put into the corrugated cardboard box to pack the products (see, for example, Patent Document 1 and Patent Document 2).

Prior Art Literature

Patent Documents

[0005] [Patent Document 1] International Publication No. 2014 / 119439 [Patent Document 2] Japanese Patent Publication No. 2019-93619 [Overview of the project] [Problems that the invention aims to solve]

[0006] In such equipment, long corrugated cardboard material, cut corrugated cardboard blanks, and assembled corrugated cardboard boxes flow continuously along a single transport path and are processed one after another in various processing sections. However, if a problem occurs in any of the processing sections, the transport of the long corrugated cardboard material is temporarily stopped. The long corrugated cardboard material drawn from the long corrugated cardboard material stack has folds formed at predetermined intervals when folded in an accordion-like manner. If these folds are located close to the leading edge of the drawn long corrugated cardboard material, when the long corrugated cardboard material is introduced into the cutting section to cut it to the required length, it is likely to come into contact with the guide member, causing the leading edge of the long corrugated cardboard material to bend. When the leading edge of the long corrugated cardboard material bends, the thickness of that section doubles, causing a paper jam. This results in the transport of the long corrugated cardboard material being stopped, and the entire corrugated cardboard box manufacturing line coming to a halt.

[0007] Furthermore, if a long corrugated cardboard material is constructed by joining multiple short corrugated cardboard materials, the joints of the long corrugated cardboard material may interfere with the process of making slits or creases when manufacturing corrugated cardboard blanks.

[0008] This invention has been made in view of the above-mentioned problems, and aims to provide a technology to prevent the production line from being stopped when drawing long corrugated cardboard material from a stack of long corrugated cardboard material and supplying it to a corrugated cardboard blank production line. [Means for solving the problem]

[0009] A first embodiment of the corrugated cardboard sheet supply device according to the present invention, which was made to solve the above problems, A conveying unit that pulls out long corrugated cardboard material from a stack of long corrugated cardboard material, which is made by folding long corrugated cardboard material in an accordion shape at predetermined folds, and conveys it along a conveying path, A long corrugated cardboard material cutting unit cuts the long corrugated cardboard material being transported along the transport path in a direction perpendicular to the transport direction, A crease detection means for detecting the presence or absence of the crease in a range of a predetermined first length or less from the leading edge of the long corrugated cardboard material being transported along the transport path, A control unit controls the long corrugated cardboard material cutting unit to perform sheet cutting, which cuts the long corrugated cardboard material at a predetermined sheet length position longer than the first length from the tip, and when the fold detection means detects a predetermined fold, to perform fold cutting, which cuts the long corrugated cardboard material at a second length position shorter than the sheet length from the tip and including the predetermined fold, It is equipped with.

[0010] The corrugated cardboard sheet supply device of the first embodiment is a device that cuts corrugated cardboard sheets, which will be the basis for corrugated cardboard blanks, from a long corrugated cardboard material folded in an accordion shape and supplies them to a corrugated cardboard blank manufacturing device. In the device with the above configuration, when a predetermined fold is detected within a range of a predetermined first length or less from the leading edge of the long corrugated cardboard material being transported along the transport path, the long corrugated cardboard material is cut from the leading edge of the long corrugated cardboard material at a second length including the fold. This eliminates the condition in which a predetermined fold exists at the leading edge of the long corrugated cardboard material, and prevents the leading edge of the long corrugated cardboard material introduced into the corrugated cardboard blank manufacturing device from bending. This enables smooth transport of the long corrugated cardboard material. The second length may be shorter or longer than the first length, as long as it includes the predetermined fold.

[0011] Furthermore, a second embodiment of the corrugated cardboard sheet supply device according to the present invention, which was developed to solve the above problems, is A conveying unit that pulls out long corrugated cardboard material from a stack of long corrugated cardboard material, which is made by folding long corrugated cardboard material in an accordion shape at predetermined folds, and conveys it along a conveying path, A long corrugated cardboard material cutting unit cuts the long corrugated cardboard material being transported along the transport path in a direction perpendicular to the transport direction, A crease detection means for detecting the presence or absence of the crease in a range between a position of a predetermined sheet length from the leading edge of the long corrugated cardboard material being transported along the transport path and a position of a predetermined first length upstream from that position, A control unit controls the long corrugated cardboard material cutting unit such that when the crease detection means detects a predetermined crease, it performs a crease-feed sheet cutting that cuts the long corrugated cardboard material at a position that is longer than the sheet length from the leading edge and includes the predetermined crease, and when the crease detection means does not detect the predetermined crease, it performs a sheet cutting that cuts the long corrugated cardboard material at a position that is the sheet length from the leading edge. It is equipped with.

[0012] In the corrugated cardboard sheet feeding device of the second embodiment, before cutting the long corrugated cardboard material, The system detects whether a predetermined fold exists around the cutting position upstream of the cutting point. If a fold is detected, the long corrugated cardboard material is cut from its leading edge at a third length including the fold. This eliminates the presence of a predetermined fold at the leading edge of the long corrugated cardboard material, preventing the leading edge of the long corrugated cardboard material from bending before being introduced into the corrugated cardboard blank manufacturing device. This allows for smooth transport of the long corrugated cardboard material. Furthermore, in the above configuration, the fold-feed sheet cutting serves both the purpose of cutting out the corrugated cardboard sheet and the purpose of removing the fold, so both cutting processes can be completed in a single step, improving the efficiency of corrugated cardboard sheet supply.

[0013] Preferably, the corrugated cardboard sheet supply device is The detection means is capable of determining whether the fold is concave or convex, and is capable of measuring the depth if the fold is concave, and the height if the fold is convex. The control unit controls the long corrugated cardboard material cutting unit to perform the fold cutting when the depth of the fold is greater than a predetermined depth value or the height is greater than a predetermined height value.

[0014] When the long corrugated cardboard material is pulled from the stack, the concave and convex folds appear alternately along the transport path. With this configuration, when the depth of the concave fold and the height of the convex fold are greater than the threshold values ​​(depth and height) used for their respective determinations, fold cutting is performed, eliminating the cause of paper jams. Furthermore, when the depth of the concave fold is shallow or the height of the convex fold is low, fold cutting is not performed, thus reducing the amount of long corrugated cardboard material that is discarded.

[0015] Furthermore, a third aspect of the corrugated cardboard sheet supply device according to the present invention, which was developed to solve the above problems, is A conveying unit that conveys a long corrugated cardboard material, which is made by joining the ends of multiple short corrugated cardboard materials, along a conveying path, A long corrugated cardboard material cutting unit cuts the long corrugated cardboard material being transported along the transport path in a direction perpendicular to the transport direction, A joint detection means for detecting the presence or absence of joints in the long corrugated cardboard material being transported along the transport path, When the presence of the aforementioned joint is detected, a control unit controls the long corrugated cardboard material cutting unit to perform a joint cutting operation, which cuts the long corrugated cardboard material at a predetermined distance upstream from the joint. It is equipped with the following features.

[0016] A corrugated cardboard sheet supplying apparatus according to the third aspect is an apparatus that cuts out a corrugated cardboard sheet, which is the base of a corrugated cardboard blank, from a long corrugated cardboard material formed by joining a plurality of short corrugated cardboard materials, and supplies the corrugated cardboard sheet to a corrugated cardboard blank manufacturing apparatus. The short corrugated cardboard material may be of any length as long as it is shorter than the long corrugated cardboard material. In the above-mentioned corrugated cardboard sheet supplying apparatus, when a joined portion exists on the long corrugated cardboard material conveyed along a conveyance path, the long corrugated cardboard material is cut in a direction orthogonal to the conveyance direction at a position a predetermined distance upstream of the joined portion. Thereby, the joined portion is removed from the long corrugated cardboard material. Then, a corrugated cardboard sheet of a predetermined length is cut out from the long corrugated cardboard material from which the joined portion has been removed, and supplied to the corrugated cardboard blank manufacturing apparatus. Therefore, when cutting out a corrugated cardboard blank from a corrugated cardboard sheet, slitting and creasing can be performed smoothly. In addition, when a corrugated box is assembled from the corrugated cardboard blank, the strength and aesthetic appearance of the box are not impaired.

[0017] In the corrugated cardboard sheet supplying apparatus according to the first to third aspects, as the crease detection means or the joined portion detection means, a line sensor provided with a plurality of image pickup elements arranged in a line in the width direction of the long corrugated cardboard material, or a camera-type laser displacement sensor can be employed. The camera-type laser displacement sensor is provided with a laser light projecting unit and a light receiving unit that receives reflected light reflected from an object, and can recognize the presence or absence of creases and joined portions in an image acquired from the camera. In addition, in a case where the detection means is configured to detect the depth of concave creases and the height of convex creases, it is preferable that the detection means is configured from a contact sensor, an ultrasonic sensor, or the like. [Effects of the Invention]

[0018] According to the first aspect of the present invention, since creases within a predetermined length range from the leading end of a long corrugated cardboard material drawn out from a stack of long corrugated cardboard materials are removed, paper jamming when introducing the long corrugated cardboard material to a cutting section is suppressed. Furthermore, in the second aspect of the present invention, since joint portions are removed from the corrugated cardboard sheet for producing corrugated cardboard blanks, slitting and creasing can be performed smoothly. In both the first and second aspects, stoppage of the corrugated cardboard blank production line is prevented. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] [Figure 1] A diagram schematically showing the configuration of a corrugated cardboard blank manufacturing apparatus provided with a corrugated cardboard sheet feeding device according to an embodiment of the present invention. [Figure 2] A top view of a conveyance path. [Figure 3] A block diagram illustrating the main control system of the corrugated cardboard blank manufacturing apparatus. [Figure 4] A diagram showing the first crease detection range in a long corrugated cardboard material, the cutting length when a crease is detected, the interval between creases, and the sheet length of a corrugated cardboard sheet. [Figure 5] A flowchart of crease cutting processing. [Figure 6A] A longitudinal sectional view near a joint portion of a long corrugated cardboard material. [Figure 6B] A diagram showing how end portions of short corrugated cardboard materials are joined to each other. [Figure 7A] A longitudinal sectional view near a joint portion of a long corrugated cardboard material. [Figure 7B] A diagram showing how end portions of short corrugated cardboard materials are joined to each other. [Figure 8A] A longitudinal sectional view near a joint portion of a long corrugated cardboard material. [Figure 8B] A diagram showing how end portions of short corrugated cardboard materials are joined to each other. [Figure 9A] A longitudinal sectional view near a joint portion of a long corrugated cardboard material. [Figure 9B] A diagram showing how end portions of short corrugated cardboard materials are joined to each other. [Figure 10] A diagram showing the joint detection range, the cutting length when a joint is detected, the fold spacing, and the sheet length of the corrugated cardboard sheet in long corrugated cardboard material. [Figure 11] Flowchart for cutting the joint. [Figure 12A] This diagram shows the second fold detection range, the feed length when a fold is detected, the fold spacing, and the sheet length of the corrugated cardboard sheet in a long corrugated cardboard material. [Figure 12B] A diagram showing the cutting line for cutting the fold-feed sheet in long corrugated cardboard material. [Figure 12C] This diagram shows a state where a corrugated cardboard sheet longer than the specified sheet length has been cut from a long corrugated cardboard material. [Figure 13A] A diagram showing the detection range for the second fold, the spacing between folds, and the sheet length of the corrugated cardboard sheet in long corrugated cardboard material. [Figure 13B] This diagram shows a state in which corrugated cardboard sheets of a predetermined length have been cut from a long roll of corrugated cardboard material. [Figure 14] Flowchart for the folding and cutting process of a sheet. [Modes for carrying out the invention]

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

[0021] <First Embodiment> <Device configuration> Figure 1 is a schematic diagram showing the configuration of the corrugated cardboard blank manufacturing apparatus 100. Figure 2 is a view from above of the conveyor path, which is part of the corrugated cardboard blank manufacturing apparatus 100. Figure 3 is a block diagram illustrating the main control system of the corrugated cardboard blank manufacturing apparatus 100.

[0022] The corrugated cardboard blank manufacturing apparatus 100 of this embodiment is an apparatus that cuts corrugated cardboard blanks 63 of appropriate length and shape from a single long corrugated cardboard material 61. In this embodiment, the long corrugated cardboard material 61 is made of double-sided corrugated cardboard. The long corrugated cardboard material 61 made of double-sided corrugated cardboard is folded in an accordion shape at predetermined folds and stacked vertically (long corrugated cardboard material stack) 60, and is pulled out from there for use.

[0023] The double-sided corrugated cardboard described above includes not only single-flute cardboard, which consists of one core and three base sheets corresponding to each of the two liners, but also multi-flute cardboard, such as "double double-sided corrugated cardboard" and "double-double double-sided corrugated cardboard," which consists of two or more cores, two liners, and one or more intermediate liners. Furthermore, there are no restrictions on the thickness or type of core (flute) of the double-sided corrugated cardboard mentioned above, and it is possible to use various types of double-sided corrugated cardboard (A-flute, B-flute, C-flute, AB-flute, AC-flute, etc.).

[0024] The corrugated cardboard blank manufacturing apparatus 100 comprises a conveying unit 10, a drawing unit 20, a first cutting unit 30, and a second cutting unit 40. The corrugated cardboard blank manufacturing apparatus 100 also comprises a control unit 50 that controls each of these units. In this embodiment, the conveying unit 10, the first cutting unit 30, and the control unit 50 constitute the corrugated cardboard sheet supply device 200. The corrugated cardboard sheet supply device 200 cuts a predetermined length of corrugated cardboard sheet 62 from a long corrugated cardboard material 61 using the first cutting unit 30 and supplies it to the second cutting unit 40.

[0025] <Conveying section 10> The transport unit 10 transports the long corrugated cardboard material 61, which is pulled out from the long corrugated cardboard material stack 60 by the pull-out unit 20, along the transport path 11.

[0026] The conveying unit 10 consists of a plurality of conveying rollers 12 arranged in a line with spacing between them, and a drive unit 13 (see Figure 3) that rotates the plurality of conveying rollers 12 synchronously. Each conveying roller 12 is supported in a horizontal position with its axial direction perpendicular to the direction of arrangement. Furthermore, the axial length of each conveying roller 12 is set to be slightly larger than the width of the long corrugated cardboard material 61.

[0027] The drive unit 13 rotates a plurality of transport rollers 12 based on commands from the control unit 50. When the transport rollers 12 rotate, the long corrugated cardboard material 61 (and the corrugated cardboard sheets 62 and corrugated cardboard blanks 63 cut from it) placed on these transport rollers 12 are transported. In this embodiment, the transport path 11 is formed by the plurality of transport rollers 12. A retaining roller 14 is provided at the upper upstream side of the transport path 11 to prevent the long corrugated cardboard material 61 from lifting off the upper surface of the transport path 11. The operation control of the drive unit 13 by the control unit 50 is performed intermittently, taking into account the processing time in the first cutting unit 30 and the second cutting unit 40.

[0028] The transport path 11 is located at a predetermined height from the floor, and a chip collection section 71 is installed below it. The chip collection section 71 collects chips generated in the first cutting section 30 and the second cutting section 40, which will be described later, and that fall through the gaps between the multiple transport rollers 12.

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

[0030] <Drawer section 20> The drawer unit 20 is used to draw out long corrugated cardboard material 61 from a stack of long corrugated cardboard material 60 placed on the floor and transport it to the transport unit 10, and comprises a rotating body 21 and a support frame 22 that rotatably supports the rotating body 21 on its rotation axis 23.

[0031] The rotating body 21 consists of a triangular tube with an equilateral triangular cross-section, and a rotation axis 23 is provided at the axial center of the triangular tube. The length of one side of the triangle in the cross-section of the triangular tube corresponds to the pitch of the folds provided in the long corrugated cardboard material 61, and the axial length of the triangular tube 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 position where the rotation axis 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] The drawer unit 20 in the above configuration draws out a predetermined length of long corrugated cardboard material 61 from the long corrugated cardboard material stack 60, aligns the portion between the folds (one pitch) with one side of the rotating body 21, and then further draws out the leading edge of the long corrugated cardboard material 61 to the location on the transport path 11 where the press roller 14 is provided. In this state, as the transport roller 12 rotates and the long corrugated cardboard material 61 is transported along the transport path 11, the rotating body 21 rotates and the long corrugated cardboard material 61 is drawn out one pitch at a time from the long corrugated cardboard material stack 60.

[0033] A rotation sensor 24 (see Figure 3) is attached to the rotation axis 23 of the rotating body 21 to detect the rotation state of the rotating body 21. The rotation sensor 24 is connected to the control unit 50 and inputs the detection result to the control unit 50. The control unit 50 uses the detection result of the rotation sensor 24 to monitor the delivery status of the long corrugated cardboard material 61.

[0034] <First cutting section 30> The first cutting unit 30 is positioned in the middle of the transport path 11 and cuts the long corrugated cardboard material 61 to a predetermined length to cut out corrugated cardboard sheets 62. The first cutting unit 30 also detects the presence or absence of folds that may cause paper jams in a range including the leading edge of the long corrugated cardboard material 61 being transported along the transport path 11, up to a predetermined length in the X direction from the leading edge (corresponding to the first length of this invention), using a sensor 33 as a fold detection means, and removes such folds if they are found. Hereinafter, this range will be referred to as the "first fold detection range".

[0035] The first cutting section 30 comprises a cutting blade 31, a lifting mechanism 32 for raising and lowering the cutting blade 31, and a sensor 33. The cutting blade 31 is supported so that its blade direction is aligned with the Y direction. The length of the cutting blade 31 in the Y direction is slightly greater than the width of the long corrugated cardboard material 61. The lifting mechanism 32 is electrically connected to the control unit 50 and raises and lowers the cutting blade 31 according to a command from the control unit 50. The first cutting section 30 corresponds to the long corrugated cardboard material cutting section in the present invention, which cuts the long corrugated cardboard material 61 in a direction perpendicular to the conveying direction.

[0036] Sensor 33 is positioned upstream of the cutting blade 31. The long corrugated cardboard material 61, pulled out from the long corrugated cardboard material stack 60, has alternating concave and convex folds when folded in an accordion shape. Sensor 33 detects whether or not a fold exists in a first fold detection range that includes the leading edge of the long corrugated cardboard material 61. 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, for example, a camera-type laser displacement sensor and comprises a laser emission unit, a MEMS (Micro Electro Mechanical Systems) mirror for adjusting the direction of propagation of the laser beam emitted from the laser emission unit, an illumination unit, and a CMOS camera. This camera-type laser displacement sensor uses the image acquired by the CMOS camera to correct the irradiation position of the laser beam and scans a predetermined area while changing the direction of propagation of the laser beam with the MEMS mirror, and acquires depth information and height information within that area. In this embodiment, the sensor 33 is positioned such that at least a part of the first fold detection range, including the leading edge 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 or convexity.

[0038] Downstream of the first cutting section 30, guide members 15 and 16 are provided to guide the corrugated cardboard sheet 62 while holding down its folds.

[0039] The control unit 50 lowers the cutting blade 31 to cut the long corrugated cardboard material 61 and performs "sheet cutting" to cut out a corrugated cardboard sheet 62 of a predetermined length (hereinafter referred to as "sheet length"). Also, when the sensor 33 scans the scan area and detects a fold that should be removed in the scan area, it controls the transport unit 10 to transport the long corrugated cardboard material 61 for a predetermined length and performs "fold cutting" by lowering the cutting blade 31 at a position upstream of the fold. The predetermined length for transporting the long corrugated cardboard 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. As a result, the area from the tip of the long corrugated cardboard material 61 including the fold is cut off. 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 cardboard material will not be wasted. Hereinafter, the length from the tip of the long corrugated cardboard material 61 to the position where fold cutting is performed (second length) will be referred to as the "cutting length". The sheet length of the corrugated cardboard sheet 62 may be a constant value, or it may be variable according to external instructions. For example, when manufacturing corrugated cardboard blanks 63 for boxes that always package products of the same shape, the sheet length is a constant value. On the other hand, when manufacturing corrugated cardboard blanks 63 for boxes that package products of various shapes, the sheet length is set to a value appropriate for the shape of each product. In this case, the sheet length may be entered by the worker, or a 3D measuring device may be installed to measure the shape of each product, and the appropriate size for each product may be calculated from the measurement results of the device.

[0040] <Second cutting section 40> The second cutting section 40 is located in the middle of the transport path 11 and downstream of the first cutting section 30. It cuts out corrugated cardboard blanks 63 from corrugated cardboard sheets 62 being transported along the transport path 11, and performs creasing and / or grooving.

[0041] The second cutting section 40 includes a cutting blade 41 and a drive mechanism 42 configured to move the cutting blade 41. The drive mechanism 42 includes, for example, a rotation drive mechanism configured to rotate the cutting blade 41 about the Z-axis, an X-direction drive mechanism configured to move the cutting blade 41 in the X-direction, and an elevation drive mechanism configured to move the cutting blade 41 up and down. The drive mechanism 42 is electrically connected to the control section 50, and moves the cutting blade 41 in accordance with a command from the control section 50.

[0042] The second cutting section 40 further includes a pressing blade 43 and a drive mechanism 44 configured to move the pressing blade 43. The drive mechanism 44 includes, for example, a rotation drive mechanism configured to rotate the pressing blade 43 about the Z-axis, an X-direction drive mechanism configured to move the pressing blade 43 in the X-direction, and an elevation drive mechanism configured to move the pressing blade 43 up and down. The drive mechanism 44 is electrically connected to the control section 50, and moves the pressing blade 43 in accordance with a command from the control section 50.

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

[0044] <Crease cutting processing in first cutting section> The crease cutting processing in the first cutting section 30 will be described with reference to FIG. 4 and FIG. 5. In FIG. 4, the spacing between creases 611 (indicated by broken lines in the drawing) of a long corrugated cardboard material 61 is denoted as P, the length of a first crease detection range 613a in the X-direction is denoted as D1, the cutting length is denoted as D2, and the sheet length of a corrugated cardboard sheet 62 is denoted as D3. The lengths D1, D2 and D3 satisfy the relationship D1<D2<D3. Furthermore, in FIG. 4, the rectangular region 330 indicated by an alternate long and short dash line is the scanning region of the sensor 33, and the thick arrows indicate cutting positions by the cutting blade 31.

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

[0046] Once a corrugated cardboard sheet 62 is cut from the long corrugated cardboard material 61, the control unit 50 performs a fold cutting process according to the flowchart shown in Figure 5. Specifically, the control unit 50 obtains detection results from the sensor 33 (step 301) and determines from the results whether or not there are folds in the scan area 330 (step 302). If it is determined that there are no folds in the scan area 330 (No in step 302), the control unit 50 transports the long corrugated cardboard material 61 for a sheet length D3 (step 308), and then lowers the cutting blade 31 to cut out the corrugated cardboard sheet 62 (step 309).

[0047] If it is determined that there is a fold within the scan area 330 (Yes in step 302), the shape of the fold is then determined. If the shape of the fold is concave (Yes in step 303), its depth value is compared with threshold B. The depth value refers to the distance from the top surface of the part of the long corrugated cardboard material 61 that does not have a fold to the deepest part of the concave fold. If the depth value is less than or equal to threshold B (No in step 305), the control unit 50 transports the long corrugated cardboard material 61 for a sheet length D3 (step 308) and lowers the cutting blade 31 (step 309). This cuts out a corrugated cardboard sheet 62 with a sheet length of D3. On the other hand, if the depth value of the concave fold is greater than threshold B (Yes in step 305), the control unit 50 transports the long corrugated cardboard material 61 for a cutting length D2 (step 306) and lowers the cutting blade 31 (step 307). This cuts off the long corrugated cardboard material 61 from the tip to a cutting length D2. Subsequently, the control unit 50 returns to step 301, and when it is confirmed from the sensor 33's detection result that the crease has been removed (No in step 302), it transports the long corrugated cardboard material 61 with a sheet length D3 (step 308). Then, it lowers the cutting blade 31 to cut the long corrugated cardboard material 61 (step 309) and cuts out a corrugated cardboard sheet 62 with a sheet length D3.

[0048] In step 303, when determining the shape of the fold, if it is determined that the shape of the fold is not concave (i.e., the shape of the fold is convex) (No in step 303), the height value of the fold is compared with threshold A. The height value of the fold refers to the distance from the top surface of the part of the long corrugated cardboard material 61 that does not have a fold to the highest point of the convex fold. If the height value is less than or equal to threshold A (No in step 304), the control unit 50 transports the long corrugated cardboard material 61 for a sheet length D3 (step 308) and lowers the cutting blade 31 (step 309). This cuts out a corrugated cardboard sheet 62 with a sheet length of D3. On the other hand, if the height value of the convex fold is greater than threshold A (Yes in step 304), the control unit 50 transports the long corrugated cardboard material 61 for a cutting length D2 (step 306) and lowers the cutting blade 31 (step 307). This cuts off the long corrugated cardboard material 61 from the tip to a cutting length D2. Subsequently, the control unit 50 returns to step 301, confirms that the crease has been removed (No in step 302), transports the long corrugated cardboard material 61 (step 308), lowers the cutting blade 31 (step 309), and cuts out a corrugated cardboard sheet 62 with a sheet length D3.

[0049] The corrugated cardboard sheet 62 with a sheet length D3, cut out by the above folding and cutting process, is fed into the second cutting section 40, where a corrugated cardboard blank 63 is cut out. At this time, since the predetermined folds have been removed from the corrugated cardboard sheet 62, paper jams in the second cutting section 40 are avoided.

[0050] The thresholds A and B described above are set to appropriate values ​​considering the material of the long corrugated cardboard material 61 and the history of paper jams. For example, thresholds A and B are set to values ​​of 0.1 to 0.7 times the thickness of the long corrugated cardboard material 61, preferably 0.2 to 0.6 times, and more preferably 0.3 to 0.5 times. Thresholds A and B may be the same value or different values. By setting appropriate values ​​for thresholds A and B, the long corrugated cardboard material 61 is cut off only when a fold exists near the tip of the long corrugated cardboard material 61 and the fold is very uneven. Therefore, it is possible to avoid paper jams while reducing the amount of long corrugated cardboard material 61 that is unnecessarily discarded.

[0051] Furthermore, it is advisable to set thresholds A and B above, taking into account the bending strength of the folds in the long corrugated cardboard material 61. Doing so will further reduce the amount of long corrugated cardboard material 61 that is unnecessarily discarded. For example, if the bending strength of the folds is 400 [mN] or less, thresholds A and B should be set to 0.1 to 0.7 times the thickness of the long corrugated cardboard material 61; if it exceeds 400 [mN], they should be set to 0.3 to 0.5 times. Thresholds A and B may be the same value or different values. The bending strength of the folds 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 it may be the same length. Also, the cutting length D2 may be a constant length, but it 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. Furthermore, in a configuration in which the cutting length D2 is changed according to the position of the fold, if the fold is located at a length D4 from the tip of the long corrugated cardboard material 61, D2 can be set to a length about 5 mm to 20 mm greater than the length D4.

[0053] In the first embodiment, the control unit 50 detects the presence or absence of a crease and the shape of the crease, and performs crease cutting only when the depth value and height value of the crease are greater than or equal to predetermined values. However, it is also possible to determine only the presence or absence of a crease and perform crease cutting whenever a crease is detected. Furthermore, if there is a difference in the frequency of paper jams in the second cutting unit 40 depending on the shape of the crease, the control unit 50 may perform crease cutting only when the shape of the crease is either concave or convex.

[0054] <Second Embodiment> The corrugated cardboard blank manufacturing apparatus according to the second embodiment differs from the corrugated cardboard blank manufacturing apparatus according to the first embodiment in that it is configured to perform a joint cutting process instead of a fold cutting process. Since the other configurations are substantially the same as those of the corrugated cardboard blank manufacturing apparatus 100 of the first embodiment, the same reference numerals are used to describe the same parts as those of the corrugated cardboard blank manufacturing apparatus 100 of the first embodiment.

[0055] The long corrugated cardboard material 61 used in the corrugated cardboard blank manufacturing apparatus of this embodiment is constructed by joining together multiple shorter corrugated cardboard materials, and the joint cutting process refers to the process of removing the joint between the short corrugated cardboard materials from the long corrugated cardboard material 61.

[0056] <Joint part> First, let's explain an example of a joint that is removed from the long corrugated cardboard material 61. Here, the two short corrugated cardboard materials that make up one joint 612 are called the first short corrugated cardboard material 614 and the second short corrugated cardboard material 615.

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

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

[0059] The joint 612 shown in Figure 8A is formed by bonding the rear end of the first short corrugated cardboard material 614 and the front end of the second short corrugated cardboard material 615 together, as shown in Figure 8B. The first short corrugated cardboard material 614 consists of one corrugated sheet 6141 and two liners 6142 and 6143, with the lower liner 6143 protruding rearward by a length L1 at the rear end of the first short corrugated cardboard material 614 (i.e., the corrugated sheet 6141 and the upper liner 6142 are not provided at the rear end of the first short corrugated cardboard material 614). On the other hand, the second short corrugated cardboard material 615 consists of one corrugated sheet 6151 and two liners 6152 and 6153. At the front end of the second short corrugated cardboard 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 of the second short corrugated cardboard material 615, and the upper liner 6152 protrudes slightly forward of the corrugated sheet 6151).

[0060] The long corrugated cardboard material 61 is formed by applying adhesive to the upper surface of the lower liner 6143 at the rear end of the first short corrugated cardboard material 614 and the lower surface of the upper liner 6152 at the front end of the second short corrugated cardboard material 615, which protrudes forward of the corrugated sheet 6151, and then bonding the two together. At this time, the rear end of the lower liner 6143 of the first short corrugated cardboard material 614 overlaps with the front end of the lower liner 6153 of the second short corrugated cardboard material 615, and the front end of the upper liner 6152 of the second short corrugated cardboard material 615 overlaps with the rear end of the upper liner 6142 of the first short corrugated cardboard material 614. As a result, overlapping portions 6144 and 6154, where two liners overlap, are formed on the upper and lower surfaces of the joint portion 612, respectively.

[0061] The joint 612 shown in FIG. 9A is formed as a result of, as shown in FIG. 9B, butting the rear end of a first short corrugated cardboard blank 614 against the front end of a second short corrugated cardboard blank 615, and adhering adhesive tapes 165 and 166 to the upper surface and the lower surface respectively across the butted portion to form a long corrugated cardboard blank 61. In this example, short corrugated cardboard blanks of general shapes are used as the first and second short corrugated cardboard blanks 614 and 615.

[0062] As shown in FIGS. 6A, 7A, 8A, and 9A, the long corrugated cardboard blank 61 formed by joining ends of two short corrugated cardboard blanks 614 and 615 has recessed strips 701 and 702 (FIG. 6A), scored lines 711 to 714 (FIG. 7A), overlapping portions 6144 and 6154 (FIG. 8A), and adhesive tapes 165 and 166 (FIG. 9A), which serve as characteristics indicating that the portion is the joint 612. Therefore, in the corrugated cardboard blank manufacturing apparatus 100 of the present embodiment, the sensor 33 is used as a joint detection means to detect whether any of these characteristics is present in the long corrugated cardboard blank 61. When it is detected that the characteristic is present, the control unit 50 lowers the cutting blade 31 at a position upstream of the characteristic, and executes "joint cutting" that removes the tip end portion of the long corrugated cardboard blank 61 including the characteristic. The joint cutting process will be described below.

[0063] <Joint Cutting Process> FIG. 10 shows a scan area 330 of the sensor 33 in the long corrugated cardboard blank 61, the sheet length D3 of the corrugated cardboard sheet 62, a cutting line 622 for cutting out the corrugated cardboard sheet 62, the joint 612, and a cutting line 621 for removing the joint 612. Further, let the length of the scan area 330 in the X direction be D5 (D5<D3). Note that although the scan area 330 of the sensor 33 in the joint cutting process is described as being the same as the scan area 330 in the crease cutting process, they may be different from each other.

[0064] In the flowchart shown in Figure 11, the control unit 50 acquires detection results from the sensor 33 (step 401) and determines from the results whether or not there is a part in the scan area 330 that exhibits the characteristics of the joint 612 (step 402). For example, in the case of the joint 612 shown in Figures 6A and 7A, the presence or absence of the joint 612 can be determined from the information regarding the depth value. Also, in the case of the joint 612 shown in Figures 8A and 9A, the presence or absence of the joint 612 can be determined from the intensity of the reflected light included in the image information of the camera equipped with the sensor 33. That is, since the intensity of the reflected light of the laser beam at the overlapping part 6154 and the adhesive tape 165 is different from the intensity of the reflected light at other locations, if a part with a different reflected light intensity is included in the scan area 330, it can be determined that the joint 612 exists.

[0065] In step 402, if the sensor 33 detects that a joint 612 exists in the scan area 330 (Yes), the control unit 50 transports the long corrugated cardboard material 61 for a length D5 (step 403), and then lowers the cutting blade 31 (step 404). This cuts the area containing the joint 612. After that, the control unit 50 transports the long corrugated cardboard material 61 for a sheet length D3 (step 405), and then lowers the cutting blade 31 to cut out the corrugated cardboard sheet 62 (step 410).

[0066] In step 402, if it is determined that no joint 612 exists in the scan area 330 (No), the control unit 50 transports the long corrugated cardboard material 61 by a length D5' (step 406) and increases the number of detections N for the joint 612 by 1 (step 407). If the product of length D5' and the number of detections N (D5' × N) is shorter than the sheet length D3 (No in step 408), the process returns to step 401 and detects again whether or not the joint 612 features are present. On the other hand, if the product of length D5' and the number of detections N (D5' × N) is longer than the sheet length D3 (Yes in step 408), the drive unit 13 is controlled to rotate the transport roller 12 in the forward or reverse direction to adjust the position so that the cutting position of the first cutting unit 30 is at a point where the length from the tip of the long corrugated cardboard material 61 is D3 (step 409), and then the cutting blade 31 is lowered to cut out the corrugated cardboard sheet 62 (step 410).

[0067] Figure 10 shows the result of detecting the presence or absence of a joint 612 in the scan area 330 three times (N=3), detecting the presence of a joint 612, and performing a cutting process (steps 403, 404) to remove the joint 612. It also shows the cutting line 621 at which the long corrugated cardboard material 61 was cut along the cutting line 621, and how the position of the cutting line 622 for cutting out the corrugated cardboard sheet 62 was changed. The changed position of the cutting line 622 is upstream of the cutting line 621 by a sheet length D3. As shown in Figure 10, by performing the joint cutting process and changing the position of the cutting line 622, it is possible to cut out a corrugated cardboard sheet 62 without a joint 612 from the long corrugated cardboard material 61.

[0068] Furthermore, if it is known in advance that the spacing between the joints 612 appearing on the long corrugated cardboard material 61 is very large compared to the sheet length D3 of the corrugated cardboard sheet, the joint cutting process may be performed once and then not performed again for a while.

[0069] Furthermore, in this embodiment, the presence or absence of features in the joint 612 is determined using the detection results of the sensor 33, but a different sensor from the sensor 33, such as a line sensor equipped with multiple image sensors (e.g., CCD imaging sensor elements or CMOS imaging elements) arranged in a line in the width direction of the long corrugated cardboard material 61, may also be used as a joint detection means.

[0070] Furthermore, although the corrugated cardboard blank manufacturing apparatus of this embodiment only performs cutting of the joint portion, it may also perform both fold cutting and joint cutting.

[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, but 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, differ from the corrugated cardboard blank manufacturing apparatus according to the first embodiment. Therefore, the same reference numerals are used for parts identical to 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 section 30 of this embodiment will be explained with reference to Figures 12A-C and 13A,B.

[0073] Fig. 12A is a diagram illustrating a range in which a crease detecting means detects a crease in a long corrugated cardboard blank 61. In the present embodiment, the crease detecting means (sensor 33) is configured to detect the presence or absence of a crease in a range between a position at a predetermined sheet length (sheet length) from the leading end of the long corrugated cardboard blank 61 conveyed along the conveying path 11, and a position of a predetermined length in the X-direction on the upstream side of said position (corresponding to the first length of the present invention). Hereinafter, said range is referred to as the "second crease detection range". In Fig. 12A, the rectangular region indicated by the one-dot chain line represents a scanning region 330 of the sensor 33, the rectangular region indicated by the two-dot chain line represents the second crease detection range 613b, and the thick arrow indicates the cutting position by the cutting blade 31. In addition, P represents the interval between creases 611 of the long corrugated cardboard blank 61, D1 represents the length in the X-direction (first length) of the second crease detection range 613b, and D3 represents the sheet length. In the present embodiment, the sensor 33 performs scanning in a region that is upstream of the cutting position by the cutting blade 31 and includes said cutting position. Therefore, the position of the long corrugated cardboard blank 61 is adjusted such that the X-direction range of the second crease detection range 613b is included in the scanning region 330.

[0074] When the sensor 33 detects that there is a crease in the second crease detection range, the control unit 50 controls the driving unit 13 of the conveying unit 10 to convey the long corrugated cardboard blank 61 to the downstream side by a predetermined length (hereinafter referred to as "feed length"). In Fig. 12A, D6 represents the feed length. The feed length is set to a value shorter than the sheet length D3 and longer than the X-direction length of the scanning region 330 (the X-direction length D1 of the second crease detection range 613b). That is, the lengths D1, D3, and D6 satisfy the relationship D1 < D6 < D3.

[0075] Figure 12B shows the state in which the long corrugated cardboard material 61 has been transported downstream by a feed length D6 minutes from the state in Figure 12A. After reaching this state, the control unit 50 lowers the cutting blade 31 from the leading edge of the long corrugated cardboard material 61 at a position that is longer than the sheet length D3 by a feed length D6 minutes (corresponding to the third length of the present invention), and performs "fold-feed sheet cutting" to cut out a corrugated cardboard sheet 62a from the long corrugated cardboard material 61. In Figure 12B, the dashed line is the cutting line 623 for cutting out the corrugated cardboard sheet 62a, and D7 indicates the length of the corrugated cardboard sheet 62a cut out by the fold-feed sheet cutting (the third length). When the fold-feed sheet cutting is performed, as shown in Figure 12C, a corrugated cardboard sheet 62a is cut out whose length in the X direction is longer than the sheet length D3 by a feed length D6 minutes.

[0076] On the other hand, as shown in Figure 13A, if the sensor 33 does not detect a fold in the second fold detection range, the control unit 50 lowers the cutting blade 31 from the tip of the long corrugated cardboard material 61 at a predetermined sheet length (sheet length) position to cut out a corrugated cardboard sheet 62b. Figure 13B shows the state after a corrugated cardboard sheet 62b with a sheet length D3 has been cut out.

[0077] In this embodiment, before cutting the long corrugated cardboard material 61, it is detected whether or not a fold exists around the cutting position upstream of the cutting position. If a fold is detected, the long corrugated cardboard material 61 is cut upstream of that fold. As a result, a corrugated cardboard sheet with a fold in the rear end is cut out, and the leading end of the next long corrugated cardboard material 61 sent will be free of folds.

[0078] Next, the specific processing will be explained with reference to the flowchart shown in Figure 14. When the long corrugated cardboard material 61 is cut, the control unit 50 transports the long corrugated cardboard material 61 for a sheet length D3 (step 501) and obtains the detection result from the sensor 33 (step 502). From the result, it determines whether or not there is a fold in the scan area 330 (step 503). If it is determined that there is no fold in the scan area 330 (No in step 503), the control unit 50 lowers the cutting blade 31 to cut out a corrugated cardboard sheet 62b with a sheet length D3 (step 509). After that, the control unit 50 returns to step 501 and repeats the subsequent steps.

[0079] If it is determined that there is a fold within the scan area 330 (Yes in step 503), the shape of the fold is then determined. If the shape of the fold is concave (Yes in step 504), its depth value is compared with threshold B. The depth value refers to the distance from the top surface of the part of the long corrugated cardboard material 61 that does not have a fold to the deepest part of the concave fold. If the depth value is less than or equal to threshold B (No in step 506), the control unit 50 lowers the cutting blade 31 (step 509). This cuts out a corrugated cardboard sheet 62b with a sheet length D3. On the other hand, if the depth value of the concave fold is greater than threshold B (Yes in step 506), the control unit 50 feeds the long corrugated cardboard material 61 for a length of D6 (step 507) and lowers the cutting blade 31 (step 508). This cuts out a corrugated cardboard sheet 62a with a length of D7 (D3 + D6) in the X direction. After that, the control unit 50 returns to step 501 and repeats the subsequent steps.

[0080] In step 504, when determining the shape of the fold, if it is determined that the shape of the fold is not concave (i.e., the shape of the fold is convex) (No in step 504), the height value of the fold is compared with threshold A. The height value of the fold refers to the distance from the top surface of the part of the long corrugated cardboard material 61 that does not have a fold to the highest point of the convex fold. If the height value is less than or equal to threshold A (No in step 505), the control unit 50 lowers the cutting blade 31 (step 509). This cuts out a corrugated cardboard sheet 62b with a sheet length D3. On the other hand, if the height value of the convex fold is greater than threshold A (Yes in step 505), the control unit 50 feeds the long corrugated cardboard material 61 for a length D6 (step 507) and lowers the cutting blade 31 (step 508). This cuts out a corrugated cardboard sheet 62a with a length D7 (D3 + D6) in the X direction. After that, the control unit 50 returns to step 501 and repeats the subsequent steps.

[0081] With the above cutting process, there are no creases at the leading edge of the long corrugated cardboard material 61, thus preventing the long corrugated cardboard material 61 from colliding with the guide members 15 and 16 provided downstream of the first cutting section 30 and bending at the leading edge. Furthermore, since the crease-feed sheet cutting (step 508) serves both the cutting for cutting out the corrugated cardboard sheet and the cutting for removing creases, both cutting processes can be completed in one step, allowing for efficient supply of corrugated cardboard sheets.

[0082] The corrugated cardboard sheets 62a with length D7 and 62b with length D3, cut out by the above cutting process, are fed into the second cutting section 40, where corrugated cardboard blanks 63 are cut out. The corrugated cardboard blanks 63 are provided with seams and flaps for making corrugated cardboard boxes, and even if the length of such parts is slightly changed, it does not affect the dimensions of the corrugated cardboard box. Therefore, in this embodiment, multiple corrugated cardboard blanks with different lengths (length in the X direction) only differing in the seams and flaps located on the upstream and / or downstream sides in the X direction, and the size of other parts being the same, are stored in a storage unit (not shown) of the control unit 50. When the corrugated cardboard sheets are fed into the second cutting section 40, the control unit 50 reads out the size of the corrugated cardboard blanks corresponding to the lengths of the corrugated cardboard sheets 62a and 62b and cuts out the corrugated cardboard blanks from the corrugated cardboard sheets.

[0083] Therefore, even if corrugated cardboard sheets have different lengths, the corrugated cardboard boxes produced by assembling the corrugated cardboard blanks cut from them will have the same dimensions. As a result, the portion that was discarded by cutting along the folds in the first embodiment is used as the corrugated cardboard blank 63, and the amount of discarded corrugated cardboard material can be reduced.

[0084] Furthermore, the corrugated cardboard blank 63 cut from the corrugated cardboard sheet 62a with length D7 may be the same size as the one cut from the corrugated cardboard sheet 62b with sheet length D3. In this case, compared to the first embodiment, the amount of discarded corrugated cardboard material remains the same, but the rear end portion including the fold of the corrugated cardboard sheet and the scraps generated when cutting the corrugated cardboard blank from the corrugated cardboard sheet can be disposed of together, preventing the discarded corrugated cardboard material from being scattered over a wide area.

[0085] Furthermore, in this embodiment, the feed length D6 for transporting the long corrugated cardboard material 61 when a fold is detected is made longer than the X-direction length D1 of the second fold detection range 613b, but it may be the same length. Also, the feed length D6 may be a constant length, but it 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. In addition, in a configuration in which the feed length D6 is changed according to the position of the fold, if the fold is located at a length D4 from the leading edge of the long corrugated cardboard material 61, the feed length D6 can be made about 5 mm to 20 mm longer than the length D4. [Explanation of Symbols]

[0086] 100...Cardboard blank manufacturing equipment 200...Cardboard sheet feeding device 10…Conveyor Unit 11…Conveyor route 12... Conveyor rollers 13…Drive unit 14…Laura 15… Guide member 16… Guide member 20...Drawer section 21…Rotational body 22...Support frame 23…Rotation axis 24... Rotation sensor 30…First cutting part 31…Cutting blade 32... Lifting mechanism 33...Sensor 40…Second cutting section 41…Cutting blade 42…Drive mechanism 43…Pressure blade 44…Drive mechanism 50…Control Unit 51... Control Panel 60... Long cardboard material stack 61…Long corrugated cardboard material 62...Cardboard sheet 62a...Cardboard sheet 62b...Cardboard sheet 63...Cardboard blank 71...Scrap collection section 165... Adhesive tape 166…Adhesive tape 611...Fold 612…Joint part 614...First short corrugated cardboard material 615...Second short corrugated cardboard material

Claims

[Claim 1] A conveying unit that pulls out long corrugated cardboard material from a stack of long corrugated cardboard material, which is made by folding long corrugated cardboard material in an accordion shape at predetermined folds, and conveys it along a conveying path, A long corrugated cardboard material cutting unit cuts the long corrugated cardboard material being transported along the transport path in a direction perpendicular to the transport direction, A crease detection means for detecting the presence or absence of the crease in a range between a position of a predetermined sheet length from the leading edge of the long corrugated cardboard material being transported along the transport path and a position of a predetermined first length upstream from that position, A control unit controls the long corrugated cardboard material cutting unit such that when the crease detection means detects a predetermined crease, it performs a crease-feed sheet cutting that cuts the long corrugated cardboard material at a position that is longer than the sheet length from the leading edge and includes the predetermined crease, and when the crease detection means does not detect the predetermined crease, it performs a sheet cutting that cuts the long corrugated cardboard material at a position that is the sheet length from the leading edge. Equipped with, The crease detection means is capable of determining whether the crease is concave or convex, and is capable of measuring the depth if the crease is concave, and the height if the crease is convex. Corrugated cardboard sheet feeding device, wherein the control unit, when the crease detection means detects a predetermined crease, cuts the sheet if the depth of the crease is less than or equal to a predetermined depth value or the height of the crease is less than or equal to a predetermined height value, and cuts the crease-feed sheet if the depth of the crease is greater than the depth value or the height of the crease is greater than the height value.

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