JP2009172842A - Method of inspecting folding precision of cardboard and device thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To facilitate discrimination of a flap end part forming a flap interval when determining the folding precision of a cardboard box by taking an image of the flap interval formed on joining part of the cardboard box in the box manufacturing process of a cardboard sheet. <P>SOLUTION: In a method of inspecting folding precision of a cardboard, the folding precision of the cardboard is determined by detecting whether the flap intervals Δf<SB>1</SB>, Δf<SB>2</SB>formed on the bonding part of the cardboard box 01 which is polymerization bonded by the bonding piece 014, and cylindrically formed and then flattened are within a normal range. The folding precision of the cardboard box is determined by detecting the flap interval by attaching a liquid or solid contrast agent (t) for coloring the cardboard sheet part S forming the flap interval or a cardboard sheet part adjacent above and below the flap interval so as to have a different color from the color of the cardboard sheet, photographing the image of the flap interval with an image-taking device 40, and extracting the flap interval from the photographed image. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention inspects the folding accuracy of a cardboard box by detecting a flap interval formed adjacent to an adhesive part of the cardboard sheet in a box making process of molding a cardboard sheet manufactured by a corrugator into a cardboard box. The present invention relates to a method and an apparatus.

  Generally, a corrugated cardboard box is formed by bonding adhesive pieces provided on the side surface of one side plate to the side plate on the other end to form a rectangular tubular body portion, and a bottom portion and a bottom portion by flaps that are continuously provided above and below each side plate. A top is formed. However, depending on how the side plates are bent, the overlapping width of the adhesive pieces may be too wide or conversely too narrow. In this case, there is an inconvenience that the intended shape cannot be obtained.

  FIG. 15A is a development view of the cardboard box 01, and the top flaps 06 to 09 and the bottom flaps 010 to 013 are connected to the side plates 02 to 05, respectively. Further, an adhesive piece 014 is integrally formed on the side plate 05 at the right end of the drawing, and as shown in FIG. 15B, the side plate 05 and the side plate 02 at the left end of the drawing are bent inward to form the adhesive piece 014 at the side plate 02. A cylindrical body is formed by polymerizing and bonding to each other. And the bottom cover and canopy of the cardboard box 01 are formed by bending the bottom flap and the top flap.

  FIG. 15B shows the corrugated cardboard box 01 that is superposed and flattened by the adhesive piece 014, and FIG. 15C is a side view of the flat corrugated cardboard box 01. FIG. When the side plate 05 and the side plate 02 are folded inward and overlapped and bonded, if the folding position deviates from the normal position, the gap between the flap 013 provided continuously to the side plate 05 and the flap 010 provided continuously to the side plate 02 (flap). (Interval) Δf is too wide or conversely too narrow. In such a state, a cardboard box having a desired shape cannot be formed.

  Therefore, it is possible to determine whether or not the bonding state of the cardboard box 01 by the adhesive piece 014 is normal by inspecting the flap interval Δf, thereby determining the folding accuracy of whether or not the folding position of the cardboard box is normal. it can.

  Patent Document 1 (Japanese Patent Laid-Open No. 9-22464) discloses a means for automatically detecting normality or failure of a joint portion of a cardboard box by detecting a flap interval Δf. This means conveys flat and corrugated flat cardboard boxes one by one with a belt conveyor, and images the flap interval Δf adjacent to both sides of the glued portion with a CCD camera from the flat corrugated cardboard boxes being conveyed. By doing so, the quality of the bonded state of the cardboard box is determined.

However, in the folding process of the box making line, after corrugated sheets are folded and joined into a square tube shape, the number of cardboard boxes is counted and stacked at the exit of the folded portion, and corrugated box groups (also called corrugated sheet batches). It is said.
At this time, the end face of the cardboard box group is pressed back and forth several times to correct the pasting state, and some cardboard boxes are conveyed to the binding machine in the state of the cardboard box group. Therefore, in the box making line after the folding and gluing process, there is no place to transport the cardboard boxes one by one, and the folding accuracy is determined after correction by the scarling. It is not possible to inspect the folding accuracy at the box line. Further, the means of Patent Document 1 has a problem that the efficiency is poor because the cardboard boxes are inspected one by one.

  Therefore, in Patent Document 2 (Japanese Patent Laid-Open No. 2001-124528) and Patent Document 3 (Japanese Patent Laid-Open No. 2001-330414), a flap interval Δf in a state of a corrugated sheet group stacked in the same direction vertically. Means capable of detecting the above are disclosed. These means include a CCD camera and an image processing device for processing images captured by the CCD camera on the exit side of the bent portion of the box making line, and images of the end faces of the stacked cardboard boxes are captured by the CCD camera. Is processed by an image processing apparatus to detect the flap interval Δf.

Japanese Patent Laid-Open No. 9-22464 JP 2001-124528 A JP 2001-330414 A

The means disclosed in Patent Document 2 or Patent Document 3 captures the end face of the corrugated cardboard sheet group with a CCD camera or the like, and detects the flap end part that forms the flap interval of the joint part from the photographed image. It measures the interval. An example of the image thus captured is shown in FIG. In FIG. 16, the cardboard box 01 is composed of a front liner paper u ₁ and a back liner paper u ₂ and a corrugated core paper n disposed between the front and back liner papers. The thickness of the front and back liner paper and the core paper is usually 0.1 to 0.2 mm, and the thickness h of the cardboard sheet is usually 1 to 5 mm. Further, the flap interval Δf is usually 3 to 9 mm.

When processing a captured image, it may be impossible to distinguish between the adjacent liner paper u ₂ depending on the state of the liner paper edge u ₃ at the flap edge to be detected. That is, if the liner paper end u ₃ sticks to the adjacent back liner paper u ₂ , the liner paper end u ₃ cannot be determined, and therefore the flap interval Δf may not be accurately measured. In this case, it cannot be determined whether the folding accuracy of the cardboard box is good.

  In view of the problems of the prior art, the present invention takes an image of the flap interval formed at the junction of the corrugated cardboard box and determines the folding accuracy of the corrugated cardboard box in the box making process of the corrugated cardboard sheet. It is an object of the present invention to make it possible to accurately determine the folding accuracy of a cardboard box by facilitating the discrimination between the flap end portion that forms the liner and the liner paper adjacent to the flap end portion.

In order to achieve the above object, the corrugated cardboard folding accuracy inspection method of the present invention comprises:
The folding accuracy of the cardboard box is determined by detecting whether or not the flap interval formed at the bonded portion of the cardboard box formed into a cylindrical shape and flattened by the adhesive piece is within a normal range. In the cardboard folding accuracy inspection method,
Colored by adhering a liquid or solid contrast agent to the corrugated cardboard sheet portion forming the flap interval or the corrugated cardboard sheet portions adjacent to the upper and lower sides of the flap interval so that the color differs from the corrugated cardboard sheet color,
The flap interval of the corrugated cardboard box is determined by capturing the flap interval with an imaging device, extracting the flap interval from the captured image, and detecting the flap interval.

In the method of the present invention, in order to easily distinguish between the flap end portions facing each other that form the flap interval formed in the adhesive portion and the liner paper adjacent to the end portion, the corrugated cardboard sheet portion that forms the flap interval or A liquid or solid contrast agent is adhered to either of the corrugated cardboard sheet portions adjacent to the upper and lower sides of the flap interval. As a result, the flap end can be clearly discriminated with respect to the adjacent liner paper, and the flap interval formed by the flap end can be accurately measured.
As the contrast agent, for example, petroleum-based paint, water-based paint, fading paint, fluorescent paint, water, visible light, fluorescent powder, or color seal may be used.

  In the method of the present invention, the time when the contrast agent is attached to the corrugated cardboard sheet is preferably performed before the corrugated cardboard sheet making process. When a contrast agent is attached to the corrugated sheet portion forming the flap interval, the contrast agent is attached to the long side edges of the four corners of the corrugated sheet group stacked up and down in the same direction before the box making process. In the corrugated cardboard box group that is stacked in the same direction up and down after being bent and bonded in the box making process, the interval between the flaps whose long side end faces are colored in the coloring process is imaged with an imaging device to detect the flap interval. Thus, the folding accuracy of the cardboard box may be determined.

  In the flat corrugated cardboard sheet before the box making process, the flap end portions to be colored are positioned at both end portions on the long side of the corrugated cardboard sheet, so that the arrangement of the contrast agent attaching device is facilitated. Then, after the folding and adhering steps of the box making process, the colored flap end is imaged with an image sensing device capable of detecting, thereby measuring the flap interval.

  In the method of the present invention, the colored region at the end of the flap is the region from the sheet end to 10-40 mm added to the bonding margin width of the adhesive piece from the sheet end, and the side adjacent to the adhesive piece side flap. In a flap, it is good to set it as the area | region from a sheet | seat edge to 10-40 mm. As a result, even after grooving and ruled lines in the box making process, it is possible to leave the colored part as long as there is no hindrance to imaging, and it does not hinder the measurement of the flap interval, and do not attach extra contrast agent. That's it.

  Further, in the method of the present invention, a colored line is formed in the direction intersecting the sheet surface on the long side side end faces of the four corners of the corrugated sheet group stacked up and down in the same direction before the box making process, and then in the flap interval detecting process. The folding accuracy of the cardboard box may be determined by detecting the interval between the colored lines after the bending adhesion.

The coloring line has a predetermined distance from the end surface on the long side. And a flap space | interval is detectable by measuring the space | interval between this coloring line after bending adhesion | attachment. Accordingly, even when it is difficult to identify the end of the flap forming the flap interval, the flap interval can be accurately measured by measuring the interval between the colored lines.
Therefore, even if the cross section of the flap end is uneven and unclear, the flap interval can be accurately measured. Further, the color or thickness of the colored line to be formed can be selected so as to facilitate measurement.

  Further, in the method of the present invention, the flap end portion that forms the flap interval and the sheet portion adjacent to the upper or lower side after bending and bonding in the box making process are calculated from the corrugated sheet width, each flap width, and the bonding margin width of the adhesive piece. And the end surface of the adjacent sheet portion is colored with a width of 10 to 40 mm, on the long side side central end surface based on the calculation result of the corrugated sheet group stacked up and down in the same direction before the box making process. In a group of corrugated boxes that are colored with a contrast agent attached and then stacked in the same direction, the folding accuracy of the corrugated boxes is determined by imaging the flap interval with an imaging device and detecting the flap interval. You may do it.

  By coloring the end surface of the sheet portion adjacent to the flap end portion that forms the flap interval after bending adhesion in the box making process, the flap end portion that forms the flap interval is improved in identification, thereby the flap interval. The flap interval can be accurately detected when a nearby area is imaged by an imaging device. In this case, the number of adhering sites is halved compared with the case where the contrast agent is adhered to the end surfaces on the long sides of the four corners of the corrugated cardboard sheet group.

In the method of the present invention, the long-side end face or the long-side central end face of the four corners of the corrugated board group before the box making process manufactured by the corrugator and stacked in the same direction in the storage area may be colored.
Thus, by coloring the corrugated cardboard sheet during storage of the corrugated cardboard sheet, it is not necessary to provide a special coloring process in the subsequent box making process. Then, the worker can easily perform coloring using a sufficient amount of time during storage in the storage site, manually or using a paint coating apparatus.

  Further, in the method of the present invention, the long sides of the four corners of the corrugated sheet group manufactured in the corrugator and stacked in the same direction up and down at the paper feed unit at the beginning of the box making line and arranged in the direction intersecting the box making line. You may make it color a side end surface or a long side center part end surface.

  In the paper feeding section of the box making line, the corrugated sheets are stacked in the same direction for the next process, and the long sides are arranged in a direction intersecting the box making line. If the cardboard sheet is colored using this time, the coloring can be easily performed. Further, in the paper feeding unit, it is easy to install a contrast agent attaching device, and the coloring work can be automated using the contrast agent attaching device.

  Further, in the method of the present invention, the corrugated board sheets are stacked in the same direction up and down after the corrugated board sheets are polymerized and bonded in the box making process, and the long sides are arranged in a direction intersecting the box making line in a planar shape. A step of correcting the bonding state of the corrugated cardboard sheets by pressing the short side of the corrugated cardboard sheet group with a pair of pressing plates arranged in parallel to each other, and after the correcting step, a flap is provided. The interval detection process may be performed.

  By pressing the corrugated cardboard sheet from the short side with a pair of pressing plates arranged in parallel with each other in the correcting step, the bonded condition of the corrugated cardboard sheet having a poor bonded condition can be considerably corrected. By performing the inspection process after the correction process, it is possible to inspect the folding accuracy quality at the product shipping stage.

  In the method of the present invention, it is preferable to use a fading paint as a contrast agent so that the color of the contrast agent disappears after the box making process is completed. As a result, the color of the contrast agent disappears after the box making process, so that the value as a product is not impaired.

The corrugated cardboard folding accuracy inspection device of the first invention for carrying out the method of the present invention comprises:
The folding accuracy of the cardboard box is determined by detecting whether or not the flap interval formed at the bonded portion of the cardboard box formed into a cylindrical shape and flattened by the adhesive piece is within a normal range. In the corrugated cardboard folding accuracy inspection device,
An attachment device main body provided with a contrast agent attaching device provided in a paper feeding section of the box making line;
A moving device that moves the adhering device body forward and backward with respect to the corrugated cardboard sheet group that is stacked in the same direction in the paper feeding unit and arranged in a direction that intersects the box making line with the long side;
A positioning member that is provided on the main body of the corrugated board and contacts the short side of the group of corrugated sheets to position the contrast agent adhering device in the contrast agent adhering region on the end surface on the long side of the corrugated board;
An image pickup device that is provided after the step of gluing and folding the box making line and picks up the flap interval;
A contrast agent is applied to the contrast agent adhesion region and colored by the contrast agent adhesion device, and the flap interval is imaged by an imaging device after the boxing line is glued and folded.

  In the paper feeder of the box making line, a plurality of corrugated cardboard sheets are stacked in the same direction up and down, and the long sides are arranged in a direction crossing the box making line. In the first device of the present invention, the contrast agent adhesion region on the long side of the corrugated cardboard sheet is colored using this time. Therefore, a contrast agent attaching device is provided in the paper feeding unit. In the device of the present invention, the attachment device main body is brought close to the corrugated cardboard sheet group arranged in the paper feeding unit. The positioning member abuts on the short side of the corrugated sheet group, thereby positioning the contrast agent attaching device in the contrast agent attaching region on the long side end surface of the corrugated board sheet. Next, the contrast agent is attached to the contrast agent attaching region by the positioned contrast agent attaching device.

  Then, after the step of gluing and folding the box making line, the flap interval formed on the adhesive portion is imaged by the imaging device, and the folding accuracy of the cardboard box is determined by detecting the flap interval from the captured image. . As described above, by providing the contrast agent attaching device in the sheet feeding section of the box making line, the contrast agent attaching region can be colored with a simple device configuration.

In the first device of the present invention, the contrast agent attaching device includes a contrast agent attaching roller capable of moving forward and backward with respect to the contrast agent attaching region on the end surface on the long side of the cardboard sheet, and the contrast agent attaching roller is used as the contrast agent attaching region. It is also possible to use a contact-type contrast agent attaching device configured to attach a contrast agent to the contrast agent attaching region by contacting the contrast agent.
Alternatively, the contrast agent attaching device includes a contrast agent attaching nozzle that is movable in a vertical direction facing the corrugated cardboard sheet, and the contrast agent is ejected from the contrast agent attaching nozzle to attach the contrast agent to the contrast agent attaching region. The non-contact type contrast agent adhering device may be configured.

  In both the apparatuses, the contrast agent can be attached to the contrast agent attaching region with a simple configuration. An air cylinder, a linear guide, or a robot arm may be used as the moving device. If an air cylinder is used, the positioning member can be soft-touched to the short side of the cardboard sheet by the elastic force of air. If the linear guide is used, the moving device can be simplified and reduced in cost. In addition, if the robot arm is used, it is possible to accurately control the three-dimensional movement of the attachment device body on which the contrast agent attaching device is mounted, and to determine the contrast agent attachment region with high accuracy.

The corrugated cardboard folding accuracy inspection apparatus of the second aspect of the present invention is:
The folding accuracy of the cardboard box is determined by detecting whether or not the flap interval formed at the bonded portion of the cardboard box formed into a cylindrical shape and flattened by the adhesive piece is within a normal range. In the corrugated cardboard folding accuracy inspection device,
A device installed between the counter ejectors for which folding is completed from the paper feeding section of the box making line, and a device for attaching a contrast agent to each corrugated cardboard sheet conveyed;
A positioning device for positioning the contrast agent adhering device in a contrast agent adhering region on an end surface on the long side of the cardboard sheet;
A sheet movement detecting device for detecting the timing of attaching the contrast agent to the cardboard sheet;
An imaging device for imaging the flap interval of the corrugated cardboard sheets provided and stacked after the boxing line gluing and folding steps;
The contrast agent is attached and colored on the contrast agent attaching region by the contrast agent attaching device, and the flap interval is imaged by an imaging device after the boxing line is glued and bent.

In the second device of the present invention, the contrast agent adhering device is provided between the counter ejectors that complete the folding from the paper feed section of the box making line and count and stack the cardboard sheets. And a contrast agent is made to adhere to the corrugated cardboard sheet conveyed one by one on the conveyor.
As described above, since the contrast agent is attached to each corrugated cardboard sheet, the contrast agent can be reliably attached to the attachment region. Further, since the contrast agent is attached to the corrugated cardboard sheet being conveyed between the paper ejecting unit of the box making line and the counter ejector, it is not necessary to provide a new coloring process.

  In the first and second devices of the present invention, along with the measurement result of the defective corrugated cardboard sheet determined that the measured folding accuracy of the corrugated cardboard sheet is worse than the set value, in what layer of the corrugated cardboard sheet group the corrugated cardboard sheets are stacked It is preferable to provide a device for displaying or recording whether or not it exists. Further, if the position information of the defective corrugated cardboard sheet is obtained from the display or recording device and the defective corrugated cardboard sheet is extracted from the stacked corrugated cardboard sheet group, the folding accuracy is determined to be poor. The cardboard sheet can be removed from the boxed cardboard sheet.

  According to the method of the present invention, a liquid or solid contrast agent is attached to the corrugated cardboard sheet portion forming the flap interval or the corrugated cardboard sheet portions adjacent to the upper and lower portions of the flap interval so that the color differs from the corrugated cardboard sheet color. The flap interval is detected after the cardboard box is molded by capturing the flap interval with an imaging device, extracting the flap interval from the captured image, and detecting the flap interval. Thus, the flap interval can be accurately measured, the determination of the folding accuracy of the corrugated cardboard sheet is facilitated, and the influence of the liner paper adjacent to the end of the flap can be reduced.

  Further, according to the first invention apparatus, an attachment apparatus main body on which a contrast agent attaching device is attached to the paper feed section of the box making line, and the attachment apparatus main body are moved forward and backward with respect to the corrugated sheet group. By providing the moving device and the positioning member for positioning the contrast agent attaching device in the contrast agent attaching region on the long side end surface of the corrugated cardboard sheet group, the contrast agent attaching region can be colored with a simple configuration. it can.

  In addition, according to the second invention apparatus, an apparatus is provided between the counter ejectors in which folding is completed from the sheet feeding unit of the box making line, and a contrast agent is attached to each corrugated cardboard sheet conveyed, and the contrast A positioning member for positioning the agent adhering device in the contrast agent adhering region on the long side end surface of the corrugated cardboard sheet, a sheet movement detecting device for detecting the timing of adhering the contrast agent to the corrugated cardboard sheet, and a gluing and folding process of the box making line And an imaging device for imaging the flap interval of the corrugated sheet group that is provided and stacked later, so that the contrast agent can be reliably adhered to the adhesion area of each corrugated sheet, and in particular, the coloring process has been renewed. It is not necessary to provide a large-scale construction of the box making line.

  Hereinafter, the present invention will be described in detail with reference to embodiments shown in the drawings. However, the dimensions, materials, shapes, relative arrangements, and the like of the component parts described in this embodiment are not intended to limit the present invention to that only, unless otherwise specified.

(Embodiment 1)
A first embodiment of the method of the present invention and the first device of the present invention will be described with reference to FIGS. FIG. 1 is an overall configuration diagram showing a box making line of a cardboard box. In FIG. 1, the right side is the starting end of the box making line, and the cardboard sheet is conveyed along the direction of arrow a to perform the box making process. On the upstream side of the box making process, as shown in FIG. 16, a corrugated cardboard sheet S made of a front liner paper u ₁ and a back liner paper u ₂ and a corrugated core paper n interposed therebetween is manufactured. The corrugated cardboard sheets S are stacked on the sheet feeding unit A.

The paper feed section A, to form a corrugated fiberboard sheet group G ₁ having a plurality of corrugated sheet S is stacked in alignment in the same direction up and down. Cardboard sheets S are fed one by one from the sheet feeding unit A to the flexographic printing unit B. In the flexographic printing section B, a total of four colors are printed on the corrugated cardboard sheet S one by one, and the printed corrugated cardboard sheet S is sent to the paper discharge section C. Thereafter, grooving and ruled lines are made in the corrugated cardboard sheet S by the die-cut portion D, and the state shown in FIG.

Thereafter, the adhesive piece 014 is glued and folded at the folding portion E, and the adhesive piece 014 is superposed and bonded to the side plate 02, whereby the rectangular cylindrical shape shown in FIGS. 15B and 15C is obtained. The cardboard box 01 is molded. Then, the cardboard box 01 is sent to the counter ejector F in the flat state, the upper and lower while being counted number in stacked are aligned in the same direction, forming a cardboard box group G ₂ for each predetermined number. Then, it is conveyed by the conveying conveyor to the binding machine arrange | positioned downstream, and is bundled there.

In the present embodiment, the coating material application device 20 shown in FIG. The coating material application device 20 applies the colored paint to the long side end surfaces of the four corners of the corrugated cardboard sheet S, and the long side end surface region is colored. Two sets of coating material application devices 20 are arranged to face the short side end surfaces s on both sides of the corrugated cardboard sheet S. Paint application apparatus 20 includes a coating apparatus main body 22 which paint application roller 21 is mounted, movably coating apparatus main body 22 with respect to the corrugated cardboard sheet group G ₁ through the guide rod 23, i.e., back and forth in the direction of the arrow b And a moving device 24 to be moved. The moving device 24 is composed of an air cylinder.

Positioning member 25 is provided in the coating apparatus main body 22, the coating apparatus main body 22 is the positioning surface 25a of the positioning member 25 is short end face s when moving toward the short end face s of the cardboard sheet group G ₁ The applicator main body 22 is positioned in contact with.
A support bracket 26 is attached to the coating apparatus main body 22 so as to be reciprocally movable in the direction of the arrow c, and a paint application roller 21 is rotatably mounted on the support bracket 26 via a support shaft 27 arranged in the vertical direction. Yes. Paint coating roller 21 has an axial length of the height of the corrugated cardboard sheet group G _1.

In a state where the coating apparatus main body 22 is positioned by the positioning member 25, by a drive device (not shown) provided in the coating apparatus main body 21, the long sides of the cardboard sheet group G ₁ paint application roller 21 is moved in the direction of arrow c It abuts on the end face l. The coating material is applied to the coating material application roller 21. In this state, the moving device 24 returns the coating device main body 22 to the moving device 24 side so that the coating material can be applied to the four corners of the long side end face l.
Since the mobile device 24 is configured by an air cylinder, may utilize the elastic force of the air, it is brought into contact with the positioning member 25 with a soft touch short end face s of the cardboard sheet group G _1. Therefore, damage the cardboard sheet group G ₁ is not.

  The coating width of the paint is set to (adhesive margin width + 10 to 20 mm) from the end on the side where the adhesive piece 014 is formed, and 10 to 20 mm from the end on the side where the adhesive piece 014 is not formed. This can leave a colored portion that can be imaged after the gluing and bending steps.

FIG. 3 shows a modification of the paint application apparatus 20 shown in FIG. In this modification, the paint application roller 21 'is rotatably mounted via a support shaft 27' that is attached to the support bracket 26 'in the horizontal direction. The support bracket 26 ′ is attached to the coating apparatus main body 22 so as to be movable up and down by the height of the corrugated cardboard group G ₁ . According to this configuration, by moving the support bracket 26 'up and down, the coating can be applied to the long-side end surface ₁ of the corrugated cardboard group G1 by the application roller 21' having a short longitudinal axial length. Therefore, the axial length of the paint application roller 21 ′ can be shortened.

FIG. 4 shows another configuration example of the coating material coating apparatus 20. In FIG. 4, members or devices having the same reference numerals as those in FIG. 2 are the same. A support bracket 26 is configured to be movable in the direction of the arrow c and in the vertical direction with respect to the coating apparatus main body 22, and a coating material application nozzle 28 that sprays the coating material t is attached to the support bracket 26. A paint supply path (not shown) is connected to the paint application nozzle 28, and the paint t is sprayed from the paint application nozzle 28 to the four corners of the end face l on the long side of the corrugated cardboard group G ₁ . With this configuration, the coating material t can be applied in a non-contact manner with the long-side end surface ₁ of the corrugated cardboard group G1.

The corrugated sheet group G ₁ coated with the paint t at the four corners of the long-side end surface 1 by the paint application device 20 provided in the paper feed unit A is sent from the flexo printing unit B of the box making line to the folding unit E. In the meantime, the adhesive piece 014 is superposed and bonded to the side plate 02 to be formed into a flat shape and formed into a flat corrugated cardboard box 01. In FIG. 5, the state in the box making process of the colored part to which the coating material was applied is schematically shown. In FIG. 5, the colored portions d formed at the four corners of the long-side end surface 1 of the corrugated cardboard sheet S in the sheet feeding portion A are bent at the folding portion E and are adjacent to each other with a flap interval.

Then, a cardboard sheet group G ₂ which are stacked aligned in the same direction up and down in the counter ejector F. Here, as shown in FIG. 6, a correction process for correcting the bonding state of the corrugated cardboard box 01 that is superposedly bonded by the side plate 02 and the adhesive piece 014 is performed.
In FIG. 6, a pair of pressure devices 30 are installed facing the short sides s ₁ and s ₂ of the cardboard box group G ₂ located on the conveyance path. The pressurizer 30 includes a pressurizer main body 31 and a pressing plate 33 connected to the pressurizer main body 31 via a pressurization rod 32 that can reciprocate in the direction of arrow e. In the figure, l ₁ and l ₂ are front side and rear side end surfaces of the cardboard box 01.

It actuates the pressure device 30 having such a structure, pressed by the pair of pressing plates 33 cardboard boxes group G ₂ from the short side s _1, s ₂ side. A pair of pressing plates 33 are arranged in parallel to each other, by pressing the corrugated board box group G ₂ from both sides in the pressing plate 33, eliminates the side plate 02 and the adhesive strip 014 relative bend which are joined together The bonding state of the cardboard box group G2 can be considerably corrected. Thus imaging the flap interval Δf adjacent the adhesive strip 014 straightening cardboard box group G ₂ by the imaging device. This imaging process will be described with reference to FIG.

7, the cardboard box group G ₂ is conveyed in the direction of arrow a, each corrugated sheet S, the flap interval Delta] f ₁ and Delta] f ₂ adjacent to the adhesive strip 014 is formed. The imaging device 40 includes cameras 41 and 42 and an image processing device (not shown). The cameras 41 and 42 are constituted by, for example, CCD cameras that can identify colors. CCD camera 41 images the front side of the vicinity of the flap interval Delta] f ₁ of the long side end surface _{l 1,} CCD camera 42 captures an image of the vicinity of the flap interval Delta] f ₂ of the long side end surface _{l 2} of the rear side.

The captured image is processed by an image processing device (not shown) to measure the flap intervals Δf ₁ and Δf ₂ . This image processing procedure will be described with reference to FIG. In FIG. 8, first, the image information sent from the CCD camera 41 or 42 is smoothed to remove uneven illumination (S10). Next, a color colored in the colored portion d is extracted from the smoothed image and converted into a binary image (S20).

  The color of the coating material t applied to the colored portion d at the adjacent flap end is preferably a color having distinguishability with respect to the color of the cardboard sheet, such as blue. The paint t may be a paint whose color disappears after the box making process is performed. For example, a paint that disappears 1 to 24 hours after application is used. As a result, no trace of paint remains in the corrugated cardboard box 01 after box making, so that the product value of the corrugated cardboard box 01 is not impaired. Examples of the paint include check marker (trade name of Inner and Outer Carbon Ink Co., Ltd.), color mark blue or red (trade name of Sakata Inx Corporation), and the like.

Next, the process of extracting only the flap intervals Δf ₁ and Δf ₂ from the image binarized in this way is repeated (S30). Such processing is sequentially performed to extract regions near the flap intervals Δf ₁ and Δf ₂ from the image. As shown in FIG. 9, the colored part d is colored with blue, for example. In the binary image, the colored portion d is extracted.

Next, the extracted images in the vicinity of the flap intervals Δf ₁ and Δf ₂ are assigned to each cardboard box by a labeling process (S 40), and the flap intervals Δf ₁ and Δf ₂ for each cardboard box are distinguished, respectively. Are calculated by multiplying the conversion factor between the image size obtained in advance and the actual size, and calculating the actual size of the flap intervals Δf ₁ and Δf ₂ (S50). The folding accuracy of each cardboard box 01 is determined from the dimensions thus calculated (S60). That is, the cardboard box 01 whose calculated dimension is out of the proper range (set value) is removed from the box making line.

In the present embodiment, in FIG. 9, the colored liner paper end u ₃ is detected, and a portion having a step in the height direction is defined as the liner paper end. In this way, the flap end portions forming the flap intervals Δf ₁ and Δf ₂ adjacent to the adhesive piece 014 of each cardboard box 01 are colored, and only the colored color is extracted from the image obtained by imaging the area near the flap interval. Since the extracted image is binarized, only the colored portion d can be clearly identified. Therefore, even when the liner paper end u ₃ at the end adjacent to the flap is attached to the adjacent liner paper u ₂ , the end u ₃ can be clearly identified. Therefore, the flap intervals Δf ₁ and Δf ₂ can be accurately measured.

Further, by arranging the varnish coating device 20 in the sheet feeding section A, since the so applied paint against the corrugated sheet group G ₁ that is stacked are aligned in the same direction up and down in the sheet feeding section A, It is not necessary to provide a special paint application part on the box making line. Therefore, the equipment cost of the box making line can be reduced. Furthermore, since the long-side end face 1 of the corrugated cardboard sheet S is arranged in a direction orthogonal to the conveyance direction a of the box making line in the paper feeding unit A, a paint is used to color the four corners of the long-side end face l. By installing the coating device 20 so as to face the end surface s on the short side, the coating material coating device 20 can be easily disposed in the vicinity of the coating region. Accordingly, the application operation is facilitated and the configuration of the positioning member 22 can be simplified.

  Moreover, in this embodiment, since the paint t from which coloring after the box making process disappears is used as the paint t, the commercial value of the corrugated cardboard box 01 after the box making is not impaired. Furthermore, since the correction step is provided before the imaging step, the folding accuracy quality in the product shipment state can be inspected.

  In the present embodiment, the coating material application device 20 is disposed in the paper feeding unit A. However, the coating material may be applied in a storage place that stores the corrugated cardboard sheet S manufactured by the corrugator. In this case, if an operator performs with a handy applicator, it can be performed at low cost.

(Embodiment 2)
Next, a second embodiment according to the method of the present invention and the first device of the present invention will be described with reference to FIGS. In the present embodiment, the paint is applied linearly at a position set in advance from the end of the long-side end surface l to the flap adjacent end portions that form the flap intervals Δf ₁ and Δf ₂ , and the colored lines i ₁ and i ₂ is formed. The coloring lines i ₁ and i ₂ are drawn parallel to the direction perpendicular to the corrugated cardboard sheet surface. The flap intervals Δf ₁ and Δf ₂ can be measured by measuring the interval I between the colored lines i ₁ and i _{2 of} the actually molded cardboard box 01.

FIG. 11 shows an example in which the coloring lines i ₁ and i ₂ are actually applied to the long side end face l. d ₁ is a coloring point actually applied to the long side end face l. Since the distance j ₁ or j ₂ from the end of each of the long side end surface l to colored line i ₁ or i ₂ is known and is set in advance, by measuring the measured interval I, the flap interval Delta] f ₁ And Δf ₂ can be measured. Then, whether the folding accuracy of the corrugated cardboard box 01 is good or not is determined based on whether or not the flap intervals Δf ₁ and Δf ₂ are in the normal range.

According to the present embodiment, even when it is difficult to determine the flap adjacent end u ₃ , it is possible to determine whether the folding accuracy of the cardboard box 01 is good or not by measuring the interval I between the colored lines i ₁ and i _2. Can do. In addition, the color or thickness of the coloring line i ₁ or i ₂ can be appropriately selected so that imaging is easy.

(Embodiment 3)
Next, a third embodiment according to the method of the present invention and the first device of the present invention will be described with reference to FIG. In the present embodiment, when the molded folded folding unit corrugated sheet S in E of box manufacturing line is a long side end surface l of the sheet portion flap adjacent ends u ₃ are adjacent those with colored region . As shown in FIG. 12, the colored region is located at the center of the long side end face l. A colored portion d is formed by applying the coating material t to the colored region.

As a result, when the corrugated cardboard sheet S is bent and formed at the folding part E, the flap adjacent end part u ₃ comes to be adjacent to the colored part d. Accordingly, the flap adjacent end u ₃ can be easily identified from the liner paper u _{2 of the} sheet portion by image processing after imaging. In this case, even if the paint t is black, it can be distinguished from the flap adjacent end u ₃ .

In the present embodiment, the paint application region is the end surface of the long side central portion of the corrugated cardboard sheet S. Therefore, painted area becomes two places a pair of corrugated cardboard sheets group G ₁ per. Basically, a paint coating apparatus having the same configuration as that shown in FIGS. 2 to 4 can be used. However, in the present embodiment, the coating material application area is halved as compared with the first embodiment, which is two places, so that the configuration of the coating material coating apparatus can be simplified accordingly.

(Embodiment 4)
Next, a fourth embodiment according to the method of the present invention and the second device of the present invention will be described with reference to FIGS. FIG. 13 shows the conveyor belt 50 disposed in the folding part E shown in FIG. The conveyor belt 50 includes four belt pieces 50a to 50d, and is arranged so that the belt pieces 50b and 50d are narrowed below the belt pieces 50a and 50c and toward the center side in the conveyance direction a. The side plate 02 of the cardboard sheet S is sandwiched between the belt piece 50c and the belt piece 50d, and the side plate 05 of the cardboard sheet S is conveyed in the conveyance direction a on the conveyance belt 50 with the belt piece 50a and the belt piece 50b interposed therebetween. Then, the side plates 02 and 05 of the cardboard sheet S are bent toward the side plates 03 and 04 of the cardboard sheet S by the belt pieces 50b and 50d.

  A pair of transmission type sheet sensors 51 a and 51 b are arranged above and below the conveyance belt 50 with the conveyance belt 50 interposed therebetween. When the transmission type sheet sensors 51a and 51b detect blocking of the reflected light by the corrugated sheet S, the tip of the cardboard sheet S reaches a predetermined position, and then the transmission type sheet sensors 51a and 51b receive the reflected light again. It is determined that the rear end of the cardboard sheet S has reached a predetermined position. On the downstream side of the transmission type sheet sensors 51 a and 51 b, contrast agent injection devices 52 a and 52 b are arranged toward the corrugated cardboard sheet S conveyed on the conveyance belt 50.

  The ejection devices 52a and 52b are supported by the positioning device 53a or 53b so as to be movable in the direction of the arrow n orthogonal to the transport direction a of the transport belt 50, and the arrow n is driven by a driving device (not shown) provided in the positioning devices 53a and 53b. It is configured to be movable in the direction.

Thus, when the controller 54 receives the corrugated sheet detection signals of the transmission type sheet sensors 51a and 51b, the conveyance speed of the cardboard sheet S, the installation positions of the transmission type sheet sensors 51a and 51b, and the installation positions of the ejection devices 52a and 52b. Based on the distance, the injection timing of the contrast agent of the injection devices 52a and 52b is calculated. Then, the corrugated sheet S is injector 52a, at the timing when reaching the installation position of 52b, a contrast agent t from the injection device 52a is injected into the long side end surface l ₁ of the cardboard sheet S leading end side, the contrast agent from the injector 52b t is sprayed onto the long side end face l ₂ on the rear end side of the cardboard sheet S.

  The ejection devices 52a and 52b are movable in the width direction of the conveying belt 50, and the shape data 55 of the corrugated cardboard sheet S, and the groove cutting and ruled line position data 56 obtained by grooving and ruling the corrugated cardboard sheet S by the die cutting part D Originally, it moves to the vicinity of the flap interval in advance. When the corrugated cardboard sheet S arrives, a contrast agent is sprayed onto the long side end face in the vicinity of the flap interval.

FIG. 14 shows an imaging device 60 and a defective cardboard sheet extraction device 70 installed in the counter ejector portion F. In FIG. 14, the long side end surfaces l ₁ and l ₂ of the corrugated cardboard sheet S are imaged by the CCD cameras 61a and 61b. Images captured by the CCD cameras 61a and 61b are sent to the controller 54, and the controller 54 performs image processing (S10 → S60) shown in FIG. Then, the actual dimensions of the calculated flap intervals Δf ₁ and Δf ₂ are compared with an appropriate range (set value) to determine whether the folding accuracy of each cardboard sheet S in the cardboard box group G ₂ is good or bad.

Further, calculating the height sensor 62 is provided, the number of the cardboard sheet S it is determined that the accuracy is poor broken, from the height of the detected height sensor 62 cardboard box group G _2, the position of the defective cardboard sheet S To do. During controller 54, recording device 63 is built to defective corrugated sheet S to record whether there many layered cardboard box group G _2.

Next, the configuration of the defective cardboard sheet S extraction device 70 will be described. Support column 72 to the holding plate 71 of the pair adjacent to the corrugated box group G ₂ which are stacked movable in the vertical direction (direction of arrow k) are erected. A space p is formed between the presser plates 71 so that exactly one cardboard sheet S can be extracted. The support column 72 is provided with a drive device 73 that moves the presser plate 71 up and down with a gap p. When the controller 54 calculates the presence and the position of the defective cardboard sheet S, the controller 54 operates the driving device 73 so that the interval p is positioned on the defective cardboard sheet S.

  On the other hand, apart from the holding plate 73, a pair of extraction arms 74, an arm main body 75 that supports the extraction arms 74 so as to be slidable in the arrow m direction, and the arm main body 75 in the vertical direction (arrow k direction) and in the horizontal direction. A drive device 76 is provided that supports the movement in the direction of arrow n and allows the distance between the extraction arms 74 to be adjusted by moving the extraction arm 74 in the direction of arrow m. The drive device 76 is provided with a display device 77 that displays the presence and position of the defective cardboard sheet S calculated by the controller 54.

The controller 54 controls the driving unit 76 moves the arm body 75 vertically or horizontally, to adjust the spacing between the extraction arms 74, on both sides from the interval p of the pressing plate 71 of the cardboard box group G ₂ The presser plate 71 is inserted into the. Then, the defective corrugated cardboard sheet S is pulled out by placing the pair of extracting arms 74 so as to surround the defective corrugated cardboard sheet S and returning the extracting arm 74 to the drive device 76 side.

According to this embodiment, the position of the corrugated cardboard sheet S conveyed by the folding unit E on the conveying belt 50 one by one is detected by the transmission type sheet sensor 51a, and the ejection device 52a is detected from the detection signal. , after calculating the time to reach the 52 b, so that so as to inject the contrast agent into the corrugated sheet S, of the cardboard sheet S leading end side and the rear side of the two long side end surface l ₁ and l ₂ The contrast agent can be accurately jetted onto the adhesion area.

Further, CCD camera 61a, and 61b result of imaging, and a height above the cardboard box group _{G 2} by the height sensor 62, the controller 54, by moving the pressing plate 71 and the extracting arms 74, a defective cardboard sheet S the so so that withdrawn from the cardboard box group G _2, it is possible to automate the extraction from the cardboard box group G ₂ of the defective cardboard sheet S.
Further, since the drive device 76 of the arm body 75 is provided with the display device 77 for displaying the presence and position of the defective cardboard sheet S, the worker can proceed with the work while confirming the position of the defective cardboard sheet S. .

  According to the present invention, in the corrugated cardboard box making process, when the flap interval formed on the adhesive portion of the corrugated cardboard sheet is imaged and the folding accuracy of the corrugated cardboard sheet is determined, the flap end that forms the flap interval is formed. By making the identification easy, it is possible to accurately determine the folding accuracy of the cardboard sheet.

1 is an overall configuration diagram of a box making line according to a first embodiment of the present invention. It is a top view of the coating material coating device which concerns on the said 1st Embodiment. It is a top view of the modification of a coating material coating device. It is a top view of another modification of a paint coating device. It is a schematic diagram of the coloring process and the bending process of the first embodiment. It is a top view of the correction process of the first embodiment. It is a perspective view of the imaging process of the first embodiment. It is a flowchart of the image processing process of the first embodiment. It is an imaging figure of the cardboard sheet of the 1st embodiment. It is a schematic diagram of the coloring process and bending process which concern on 2nd Embodiment of this invention. It is an imaging figure of the corrugated cardboard sheet of the second embodiment. It is a schematic diagram of the coloring process and bending process which concern on 3rd Embodiment of this invention. It is a perspective view of a contrast agent adhesion device concerning a 4th embodiment of the present invention. It is a perspective view of the imaging device concerning the 4th embodiment. (A) is a plan view of the corrugated cardboard sheet, (b) is a plan view of the corrugated cardboard box 01 after being bent and bonded, and (c) is a side view of the end face on the long side of the cardboard box. It is an imaging figure of the long side end surface of the conventional cardboard box.

Explanation of symbols

01 Corrugated box 06-09 Top flap 010-013 Bottom flap 014 Adhesive piece 20 Paint coating device 21 Paint coating roller 22 Coating device main body 24 Moving device 25 Positioning member 28 Paint coating nozzle 30 Pressure device 33 Press plate 40, 60 Imaging device 51a, 51b Transmission type sheet sensor (sheet movement detecting device)
52a, 52b Contrast agent injection device 53a, 53b Positioning device 54 Controller 62 Height sensor 63 Defective corrugated cardboard sheet recording device 70 Defective corrugated cardboard sheet extractor 71 Presser plate 74 Extraction arm 77 Defective corrugated cardboard sheet display device d Coloring part Δf, Δf ₁ , Delta] f ₂ flaps intervals i _{1, i 2} colored line _l, l 1, the long side end surface s of the _{l 2} cardboard _sheets, s 1, _{s 2-stage} short end face t paint G ₁ cardboard sheet group G ₂ cardboard box ball seat Group S Cardboard sheet

Claims (17)

The folding accuracy of the cardboard box is determined by detecting whether or not the flap interval formed at the bonded portion of the cardboard box formed into a cylindrical shape and flattened by the adhesive piece is within a normal range. In the cardboard folding accuracy inspection method,
Colored by adhering a liquid or solid contrast agent to the corrugated cardboard sheet portion forming the flap interval or the corrugated cardboard sheet portions adjacent to the upper and lower sides of the flap interval so that the color differs from the corrugated cardboard sheet color,
A corrugated cardboard folding accuracy inspection method characterized in that the folding accuracy of a corrugated cardboard box is determined by capturing the flap interval with an imaging device, extracting the flap interval from the captured image, and detecting the flap interval.   2. The corrugated cardboard folding accuracy inspection method according to claim 1, wherein the contrast agent is a petroleum paint, water-based paint, fading paint, fluorescent paint, water, visible light, fluorescent powder, or a color seal. Prior to the box making process, the contrast agent is attached to the corners of the four corners of the corrugated cardboard sheets stacked up and down in the same direction and colored,
In a group of corrugated boxes stacked in the same direction up and down after being bent and bonded in the box making process, the interval between the flaps whose long side end faces are colored in the coloring step is imaged with an imaging device to detect the flap interval. The corrugated cardboard folding accuracy inspection method according to claim 1, wherein the folding accuracy of the corrugated cardboard box is determined by:   In the flap on the adhesive piece side, the colored area by the contrast agent is an area from the sheet end to 10-40 mm added to the bonding margin width of the adhesive piece, and in the flap adjacent to the adhesive piece side flap, from the sheet end. The corrugated cardboard folding accuracy inspection method according to claim 1 or 3, wherein the area is 10 to 40 mm. Before the box making process, form colored lines in the direction intersecting the sheet surface at the long side end face of the four corners of the corrugated sheet group stacked up and down in the same direction,
4. The corrugated board folding accuracy inspection method according to claim 3, wherein in the flap interval detecting step, the folding accuracy of the cardboard box is determined by detecting an interval between the colored lines after the bending adhesion. Calculate the flap end and the sheet portion adjacent to the upper or lower side after folding and bonding in the box making process from the cardboard sheet width, each flap width and the bonding margin width of the adhesive piece, Colored by attaching a contrast agent to the long side side central end face based on the calculation result of the corrugated cardboard sheets stacked up and down in the same direction before the box making process so that the end face is colored with a width of 10 to 40 mm. And
The corrugated cardboard boxes stacked in the same direction in the upper and lower directions are then used to determine the folding accuracy of the cardboard boxes by imaging the flap interval with an imaging device and detecting the flap interval. 4. The method for inspecting the accuracy of corrugated cardboard breakage according to 3.   The long side side end face or the long side side central part end face of the four corners of the corrugated cardboard sheet group before the box making process, which is manufactured by a corrugator and stacked in the same direction vertically in the storage area, is colored. The corrugated cardboard folding accuracy inspection method described in 1.   Long edge side end surface or long side side center of the four corners of corrugated cardboard sheets manufactured in a corrugator and stacked in the same direction up and down at the paper feed unit at the start end of the box making line and arranged in the direction intersecting the box making line The corrugated cardboard folding accuracy inspection method according to claim 3 or 6, wherein the end face of the part is colored. After the corrugated cardboard sheets are superposed and bonded by adhesive pieces in the box making process, the corrugated cardboard groups arranged in the direction intersecting the box making line with the long sides stacked in the same direction up and down have a flat pressing surface. A step of correcting the bonding state of the cardboard sheets by pressing the short side of the cardboard sheet group with a pair of pressing plates arranged in parallel;
7. The corrugated cardboard folding accuracy inspection method according to claim 3, wherein the flap interval detection step is performed after the correction step.   2. The corrugated cardboard folding accuracy inspection method according to claim 1, wherein a fading paint is used as the contrast agent, and the coloring of the contrast agent disappears after completion of the box making process. The folding accuracy of the cardboard box is determined by detecting whether or not the flap interval formed at the bonded portion of the cardboard box formed into a cylindrical shape and flattened by the adhesive piece is within a normal range. In the corrugated cardboard folding accuracy inspection device,
An attachment device main body provided with a contrast agent attaching device provided in a paper feeding section of the box making line;
A moving device that moves the adhering device body forward and backward with respect to the corrugated cardboard sheet group that is stacked in the same direction in the paper feeding unit and arranged in a direction that intersects the box making line with the long side;
A positioning member that is provided on the main body of the corrugated board and contacts the short side of the group of corrugated sheets to position the contrast agent adhering device in the contrast agent adhering region on the end surface on the long side of the corrugated board;
An image pickup device that is provided after the step of gluing and folding the box making line and picks up the flap interval;
Corrugated cardboard folds characterized in that the contrast agent is attached to the contrast agent attachment region and colored by the contrast agent attachment device, and the flap interval is picked up by an image pickup device after the boxing line is glued and folded. Accuracy inspection device.   The contrast agent attaching device includes a contrast agent attaching roller capable of moving back and forth with respect to a contrast agent attaching region on a long side end surface of the corrugated cardboard sheet, and the contrast agent attaching roller is brought into contact with the contrast agent attaching region. The corrugated cardboard folding accuracy inspection device according to claim 11, which is a contact type contrast agent adhering device configured to adhere a contrast agent to an adhering region.   The contrast agent attaching device includes a contrast agent ejecting nozzle that is movable in a vertical direction facing the corrugated cardboard sheet, and the contrast agent is ejected from the contrast agent ejecting nozzle so as to attach the contrast agent to the contrast agent attaching region. The corrugated cardboard folding accuracy inspection device according to claim 11, which is a non-contact type contrast agent adhering device configured as described above.   The corrugated cardboard folding accuracy inspection device according to claim 11, wherein the moving device is an air cylinder, a linear guide, or a robot arm. The folding accuracy of the cardboard box is determined by detecting whether or not the flap interval formed at the bonded portion of the cardboard box formed into a cylindrical shape and flattened by the adhesive piece is within a normal range. In the corrugated cardboard folding accuracy inspection device,
A device installed between the counter ejectors for which folding is completed from the paper feeding section of the box making line, and a device for attaching a contrast agent to each corrugated cardboard sheet conveyed;
A positioning device for positioning the contrast agent adhering device in a contrast agent adhering region on an end surface on the long side of the cardboard sheet;
A sheet movement detecting device for detecting the timing of attaching the contrast agent to the cardboard sheet;
An imaging device for imaging the flap interval of the corrugated cardboard sheets provided and stacked after the boxing line gluing and folding steps;
Corrugated cardboard folds characterized in that the contrast agent is attached to the contrast agent attachment region and colored by the contrast agent attachment device, and the flap interval is picked up by an image pickup device after the boxing line is glued and folded. Accuracy inspection device.   An apparatus for displaying or recording a measurement result of a defective corrugated cardboard sheet in which the measured folding accuracy of the corrugated cardboard sheet is worse than a set value and the number of layers of the corrugated cardboard sheet group in which the defective corrugated cardboard sheets are stacked The corrugated cardboard folding accuracy inspection apparatus according to claim 1 or 15, further comprising:   The corrugated cardboard folding accuracy inspection according to claim 16, further comprising a sampling device that obtains positional information of the defective corrugated cardboard sheets from the display or recording device and extracts the defective corrugated cardboard sheets from the stacked cardboard sheet group. apparatus.

Images