WO2018003490A1 - Device for detecting splices on corrugated cardboard sheet, device for manufacturing corrugated cardboard sheet, and corrugated cardboard sheet - Google Patents

Abstract

A device for detecting splices on a corrugated cardboard sheet, a device for manufacturing a corrugated cardboard sheet, and a corrugated cardboard sheet are provided. The device for detecting splices on a corrugated cardboard sheet is provided with: a marking device (51) that uses a visualizing agent that becomes invisible after a specified period of time set in advance elapses after bonding of a front liner (A), a corrugated inner core (B), and a back liner (C), to apply a mark (M) to each splice (90) on the front liner (A), the inner core (B), and the back liner (C); a mark detection device (52) that detects the mark (M) applied by the marking device (51) before the specified period of time elapses; and a control device (53) that controls the marking device (51) and the mark detection device (52).

Description

Cardboard sheet splice detection device, corrugated sheet manufacturing device, corrugated sheet

The present invention relates to a cardboard sheet splicing part detecting device for detecting a paper splicing part of a corrugated cardboard sheet in which a front liner, a corrugated core paper and a back liner are bonded, and a corrugated cardboard sheet having a corrugated sheet splicing part detecting device. And a corrugated cardboard sheet manufactured by a corrugated cardboard sheet manufacturing apparatus.

A corrugating machine as a corrugated sheet manufacturing apparatus includes a single facer that forms a single-sided cardboard sheet and a double facer that forms a double-sided cardboard sheet by bonding a front liner paper to the single-sided cardboard sheet. A single facer forms a corrugated core paper (core) into a corrugated shape, and a back liner is laminated to form a single-sided cardboard sheet. A double facer forms a double-sided cardboard sheet by laminating a front liner to the single-sided cardboard sheet. . A continuous double-sided corrugated cardboard sheet produced by this double facer is cut to a predetermined width by a slitter scorer and cut to a predetermined length by a cut-off device to form a plate-like corrugated cardboard sheet.

In this corrugating machine, the front liner, core paper, and back liner are sheets supplied from roll paper held on a mill roll stand. The mill roll stand holds a plurality of roll papers, and when one of the roll papers remains, the other roll paper is spliced by the splicer so that the sheets can be continuously fed out. However, since the paper splicing portion of the sheet is processed as a defective portion that cannot be a product, it is necessary to detect the paper splicing portion during the manufacture of the corrugated cardboard sheet, and to cut and remove it. Conventionally, a metal plate made of aluminum or the like is attached to the paper joint portion of the sheet, and the paper joint portion is detected via the metal plate by a metal sensor.

However, in recent years, speeding up of corrugating machines has been demanded, and the sheet being conveyed may meander, so that the metal sensor cannot detect the metal plate, and the paper joint is shipped as a product together with the metal plate. There is a risk that. As what solves such a problem, there exist some which were described in the following patent document, for example. The paper splicing position detection device described in Japanese Patent Application Laid-Open No. 2004-228561 detects and excludes a paper splicing portion by coloring a splicing portion of a sheet and detecting the colored portion. Further, the corrugator splice detection method and apparatus described in Patent Document 2 includes a sheet to be detected interposed in a paper splice of the sheet, and detects and excludes the splice by detecting the detected sheet. To do.

Japanese Utility Model Publication No. 01-161026 JP 2009-045909 A

The above-described paper splicing position detection device disclosed in Patent Document 1 detects and excludes a paper splicing portion by detecting a colored portion provided with a splicing portion of a sheet. If it cannot be detected, the corrugated cardboard sheet having the colored portion is shipped as a product. In addition, the corrugator paper splice detection method and apparatus disclosed in Patent Document 2 detects and excludes a paper splice by detecting a detection sheet interposed in a paper splice. It is necessary to prepare a detection sheet and interpose it in the sheet splicing portion of the sheet, which complicates the operation.

SUMMARY OF THE INVENTION The present invention solves the above-described problems, and an object thereof is to provide a corrugated sheet joint detection device, a corrugated sheet manufacturing device, and a corrugated sheet that improve the quality of the corrugated sheet.

In order to achieve the above object, a corrugated sheet detecting device for corrugated cardboard sheets according to the present invention is a corrugated board for detecting a spliced portion in a corrugated sheet in which a first liner, a corrugated core paper, and a second liner are bonded together. In the sheet splice detection device, the first liner and the first liner can be used with a visual invisible agent after a predetermined time has elapsed since the first liner, the core paper, and the second liner are pasted together. A mark applying device that applies a mark to each splicing portion of the core paper and the second liner, and a mark detection device that detects the mark applied by the mark applying device before the predetermined time has elapsed. It is characterized by.

Accordingly, when the mark applying device applies a mark to the first liner, the core paper, and the second liner using the visualizing agent, the mark detection device detects the mark applied to the first liner, the core paper, and the second liner. To do. Here, if the corrugated cardboard sheet having the paper splicing portion detected based on the mark is removed, the paper splicing portion is not mixed into the corrugated cardboard sheet to be a product. In addition, even if the cardboard sheet having the mark provided by the mark applying device could not be removed, the mark is formed with a visual invisible agent after a predetermined time has passed. As a result, the quality of the corrugated cardboard sheet can be improved.

The cardboard sheet splice detection device of the present invention is characterized in that the visual recognition agent is an ultraviolet light emitting ink.

Therefore, by using UV light emitting ink as the visualizing agent, it is possible to form marks without coloring the first liner, the core paper, and the second liner, and prevent the colored portion from being mixed into the corrugated cardboard sheet that is the product. be able to.

The cardboard sheet splice detection device of the present invention is characterized by having an ultraviolet irradiation unit and an imaging unit that images the mark emitted by irradiating ultraviolet rays.

Therefore, the ultraviolet irradiation unit irradiates ultraviolet rays toward the mark formed with the ultraviolet light emitting ink, and the imaging unit images the mark emitted by irradiating the ultraviolet rays, and the mark is visualized and easily detected. can do.

The cardboard sheet splice detection device of the present invention is characterized in that the visualizing agent is a decolorizable ink.

Therefore, by using the decolorizable ink as the visualizing agent, the marks formed on the first liner, the core paper, and the second liner will be erased over time, and the colored portion on the corrugated cardboard sheet that will be the product Can be prevented.

In the splicing portion detecting apparatus for corrugated cardboard sheets according to the present invention, the mark applying device applies a mark after splicing in the first liner, the core paper, and the second liner, and the mark detecting device includes the first detecting device. The mark is detected before the liner and the core paper are pasted together.

Therefore, the first liner, the core paper, and the second liner are provided with a mark after the paper splicing, and the mark is detected before the bonding, so that the paper splicing portion can be accurately detected via the mark. .

In the paper splice detection device for corrugated cardboard sheets according to the present invention, the mark applying device applies a mark to a central portion in the width direction of the first liner, the core paper, and the second liner.

Therefore, by applying a mark to the center of the first liner, the core paper, and the second liner in the width direction, the mark application position changes even if the widths of the first liner, the core paper, and the second liner are changed. Therefore, it is not necessary to adjust the position of the mark applying device or the mark detecting device.

In the cardboard sheet splice detection device of the present invention, the mark applying device applies a mark to a surface of the first liner to which the core paper is attached.

Therefore, the first liner is marked on the surface of the corrugated cardboard sheet that is the product even if the mark cannot be completely removed because the mark is applied to the surface on which the core paper is pasted. It will never be done. Further, when printing is performed on the surface of the corrugated cardboard sheet in a post-process after manufacturing the corrugated cardboard sheet, there is no mark on the surface of the first liner where the core paper is not pasted, which causes a printing failure due to the mark. There is nothing.

In the cardboard sheet splice detection device of the present invention, the mark applying device applies a mark to a surface to which the second liner and the core paper are not attached.

Therefore, by providing a mark on the surface where the second liner and the core paper are not pasted, the mark detection device can detect the mark with high accuracy.

In the paper splice detection device for corrugated cardboard sheets according to the present invention, the mark detection device detects the mark along a perpendicular line from the top of the corrugated step of the core paper toward the second liner.

Therefore, the mark detection device detects the mark along the perpendicular line from the top of the corrugation of the core paper to the second liner, so that the mark is not blocked by the corrugation of the core paper and the mark detection device Marks can be detected with high accuracy.

In the paper splice detection device for corrugated cardboard sheets according to the present invention, a control device for controlling the mark applying device is provided, and the mark applying device applies the mark to the first liner, the core paper, and the second liner by coating. The control device adjusts the coating time by the mark applying device according to the conveyance speed of the first liner, the core paper, and the second liner.

Therefore, by adjusting the coating time by the mark applying device according to the conveying speed of the first liner, the core paper, and the second liner, even if the conveying speed of the first liner, the core paper, and the second liner changes, The length can be maintained constant, the mark detection device can detect the mark with high accuracy, and the increase in the defective length of the first liner, the core paper, and the second liner on which the mark is formed is suppressed. be able to.

The corrugated sheet manufacturing apparatus of the present invention includes a first liner, a core paper, a paper splicing device that splices the preceding sheet and the succeeding sheet in the second liner, and a second liner attached to the corrugated core paper. A single facer for manufacturing a single-sided cardboard sheet, a double facer for manufacturing a double-sided cardboard sheet by bonding a first liner to the core paper side of the single-sided cardboard sheet, and a paper splice detection device for the cardboard sheet, And a sheet removing device for removing the paper splicing portion detected by the paper splicing portion detecting device for the corrugated cardboard sheet from the conveying line.

Therefore, the splicing device performs the splicing of the preceding sheet and the succeeding sheet in the first liner, the core paper, and the second liner, and the single facer bonds the second liner to the corrugated core paper. A single-sided cardboard sheet is manufactured, and the double facer manufactures a double-sided cardboard sheet by bonding the first liner to the core paper side of the single-sided cardboard sheet manufactured by a single facer. At this time, the mark applying device applies a mark to the first liner, the core paper, and the second liner using a visualizing agent, and the mark detection device applies the mark applied to the first liner, the core paper, and the second liner. The sheet removing device detects and removes the corrugated cardboard sheet having the paper splicing portion from the conveyance line based on the detected mark position. For this reason, the paper splicing portion is not mixed into the corrugated cardboard sheet as a product. In addition, even if the cardboard sheet having the mark provided by the mark applying device could not be removed, the mark is formed with a visual invisible agent after a predetermined time has passed. As a result, the quality of the corrugated cardboard sheet can be improved.

In the corrugated cardboard sheet manufacturing apparatus of the present invention, the corrugated cardboard sheet splicing part detecting device controls the operation timing of the mark applying device based on a splicing signal from the splicing device.

Therefore, by controlling the operation timing of the mark applying device based on the paper splicing signal from the paper splicing device, it is possible to accurately apply marks to the splicing portions of the first liner, the core paper, and the second liner.

In the corrugated sheet manufacturing apparatus of the present invention, a glue machine for applying glue is provided on the core paper side of the single-sided cardboard sheet, and the mark detection device is located upstream in the conveyance direction of the single-sided cardboard sheet in the glue machine. It is characterized by being provided in.

Therefore, since the mark detection device detects the mark before applying glue on the core paper side of the single-sided cardboard sheet, the mark detection device can accurately detect the mark on the single-sided cardboard sheet without the glue interfering. Can do.

In the corrugated sheet manufacturing apparatus of the present invention, a glue machine that applies glue to the core side of the single-sided cardboard sheet is provided, and the mark detection device is downstream in the conveyance direction of the single-sided cardboard sheet in the glue machine. It is characterized by being provided in.

Therefore, since the mark detection device detects the mark after applying glue on the core paper side of the single-sided cardboard sheet, the mark detection device can accurately detect the mark on the single-sided cardboard sheet expanded and contracted by the glue. .

Further, the corrugated cardboard sheet of the present invention is provided with a mark formed of an invisible visual recognition agent at the end of the corrugated cardboard sheet in which the first liner, the corrugated core paper, and the second liner are bonded together. It is characterized by.

Therefore, even if the visual recognition material used for removing the paper splice portion remains on the corrugated cardboard sheet, it cannot be visually recognized, so that the quality of the corrugated cardboard sheet can be improved.

According to the corrugated sheet joint detection device, corrugated sheet manufacturing apparatus, and corrugated sheet of the present invention, a mark is given to the joint using a visual agent that is not visible when a predetermined time elapses. Since it detects before progress of time, a colored part does not mix in the corrugated board sheet used as a product, As a result, the improvement of the quality of a corrugated board sheet can be aimed at.

FIG. 1 is a schematic view showing a corrugating machine as a corrugated board manufacturing apparatus of the present embodiment. FIG. 2 is a schematic configuration diagram illustrating the corrugated sheet sheet splice detection device according to the present embodiment. FIG. 3 is a schematic diagram showing a splicer in which a mark applying device is arranged. FIG. 4 is a schematic diagram showing a preheater, a glue machine, and a double facer in which a mark detection device is arranged. FIG. 5 is a schematic diagram showing a pre-heater, a glue machine, and a double facer in which mark detection devices are arranged at different positions. FIG. 6 is a schematic diagram illustrating a sheet splicing method. FIG. 7 is a schematic diagram illustrating a method of applying a mark to a sheet. FIG. 8 is a schematic diagram illustrating a mark detection method on a sheet.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of a corrugated sheet joint detection device, corrugated sheet manufacturing apparatus, and corrugated sheet according to the present invention will be described in detail below with reference to the accompanying drawings. In addition, this invention is not limited by this embodiment, and when there are two or more embodiments, what comprises combining each embodiment is also included.

FIG. 1 is a schematic diagram showing a corrugating machine as a corrugated board sheet manufacturing apparatus according to this embodiment.

In this embodiment, as shown in FIG. 1, a corrugating machine 10 as a corrugated board manufacturing apparatus has a corrugated core (core paper) B as a second liner, for example, a back liner C bonded together. A single-sided corrugated cardboard sheet D is manufactured, and, for example, a front liner A is bonded to the core B side of the manufactured single-sided corrugated cardboard sheet D to form a double-faced corrugated cardboard sheet E. The plate-shaped double-sided cardboard sheet F is manufactured by cutting into lengths.

The corrugating machine 10 includes a mill roll stand 11 with a core B, a preheater (preheating device) 12, a mill roll stand 13 with a back liner C, a preheater (preheating device) 14, a single facer 15, and a bridge 16. , A roll roll stand 17 of the front liner A, a preheater (preheating device) 18, a glue machine 19, a double facer 20, a rotary shear 21, a slitter scorer 22, a cut-off 23, a defective product discharge device 24, A stacker 25 is provided.

The mill roll stand 11 is provided with a roll paper in which a core paper having a core B formed on both sides is wound in a roll shape, and a splicer (paper splicing device) 31 for performing paper splicing is provided above the mill roll stand 11. Is provided. When paper is fed from one roll paper, the other roll paper is loaded and paper splicing preparation is made. When the remaining base paper of one roll paper becomes small, the splicer 31 joins the base paper of the other roll paper. Then, while the base paper is being supplied from the other roll paper, one roll paper is loaded and paper splicing preparation is made. In this way, the base paper is sequentially spliced and continuously fed from the mill roll stand 11 toward the downstream side.

On the other hand, the mill roll stand 13 is provided with roll paper on which the back liner C is wound in rolls on both sides, and a splicer 32 for performing paper splicing is provided above the roll paper. When paper is fed from one roll paper, the other roll paper is loaded and paper splicing preparation is made. When the remaining base paper of one roll paper is reduced, the splicer 32 joins the base paper of the other roll paper. Then, while the base paper is being supplied from the other roll paper, one roll paper is loaded and paper splicing preparation is made. In this way, the base paper is sequentially spliced and continuously fed from the mill roll stand 13 toward the downstream side.

The preheaters 12 and 14 preheat the core B and the back liner C, respectively. Each preheater 12 and 14 has a heating roll to which steam is supplied inside, and the base paper (core B, back liner C) continuously fed from the mill roll stands 11 and 13 is used as this heating roll. The base paper is heated to a predetermined temperature by being wound and conveyed.

The single facer 15 forms the single-sided cardboard sheet D by pasting the core B heated by the preheater 12 into a corrugated shape and then gluing the core B to the top of each step and bonding the back liner C heated by the preheater 14. The single facer 15 is provided with a take-up conveyor 30 obliquely upward on the downstream side in the transport direction. The take-up conveyor 30 is composed of a pair of endless belts, and has a function of sandwiching a single-sided cardboard sheet D formed in the single facer 15 and conveying it to the bridge 16. The bridge 16 functions as a retaining portion for temporarily retaining the single-sided cardboard sheet D in order to absorb the speed difference between the single facer 15 and the double facer 20.

The roll roll 17 is provided with roll paper on which the front liner A is wound in rolls on both sides, and a splicer 33 for performing paper splicing is provided above the roll roll stand 17. When paper is fed from one roll paper, the other roll paper is loaded and paper splicing preparation is made. When the remaining base paper of one roll paper becomes small, the splicer 33 joins the base paper of the other roll paper. Then, while the base paper is being supplied from the other roll paper, one roll paper is loaded and paper splicing preparation is made. In this way, the base paper is sequentially spliced and continuously fed from the mill roll stand 17 toward the downstream side.

The preheater 18 has preheating rolls 34, 35 and 36 arranged in the vertical direction. The preheating roll 34 is for heating the front liner A, the preheating roll 35 is for heating the single-sided cardboard sheet D, and the preheating roll 36 is for heating the single-sided cardboard sheet D1. The front liner preheating roll 34 has a winding amount adjusting device, is supplied with steam inside and heated to a predetermined temperature, and the front liner A is wound around the peripheral surface. It can be preheated. The preheating roll 35 for a single-stage sheet has a winding amount adjusting device, is supplied with steam inside and heated to a predetermined temperature, and the back liner C side of the single-sided cardboard sheet D is wound around the circumferential surface. This single-sided cardboard sheet D can be preheated.

The preheating roll 36 for a single-stage sheet has a winding amount adjusting device, is supplied with steam inside and heated to a predetermined temperature, and the back liner C side of the single-sided cardboard sheet D1 is wound around the peripheral surface. This single-sided cardboard sheet D1 can be preheated. The single-sided cardboard sheet D1 is conveyed from a single facer (not shown). When the cardboard sheet to be manufactured is a double-sided cardboard sheet F in which the front liner A, the core B, and the back liner C are laminated, the preheating roll 36 is not used, and the cardboard sheet to be manufactured is the front liner A and the core B. In the case of a double-sided cardboard sheet in which the back liner C, the core B, and the back liner C are laminated, a preheating roll 36 is used.

Glue machine 19 has gluing rolls 37 and 38 arranged in the vertical direction. The gluing roll 37 is for gluing in contact with each top of the step of the core B in the single-sided cardboard sheet D heated by the preheating roll 35. The gluing roll 38 is for gluing by contacting each top of the step of the core B in the single-sided cardboard sheet D1 heated by the preheating roll 36. The single-sided cardboard sheets D and D1 glued by the glue machine 19 are transferred to the double facer 20 of the next process. The front liner A heated by the preheating roll 34 is also transferred to the double facer 20 through the glue machine 19.

The double facer 20 is divided into a heating section 39 on the upstream side and a cooling section 40 on the downstream side along the traveling line of the single-sided cardboard sheet D and the front liner A. The single-sided corrugated cardboard sheet D glued by the glue machine 19 is carried between the pressure belt 41 and the hot plate 42 by the heating section 39, and the front liner A is disposed on the core B side of the single-sided cardboard sheet D. Are carried between the pressure belt 41 and the heat plate 42 so as to overlap with each other. Then, after the single-sided cardboard sheet D and the front liner A are carried between the pressure belt 41 and the hot platen 42, the single-sided cardboard sheet D and the front liner A are integrally transferred toward the cooling section 40 in a state where they are overlapped vertically. During this transfer, the single-sided cardboard sheet D and the front liner A are heated while being pressurized, so that they are bonded together to form a continuous double-sided cardboard sheet E. The double-sided corrugated cardboard sheet E is naturally cooled when being conveyed in the cooling section 40 while being sandwiched between the pressure belt 41 and the conveyance belt 43.

The double-sided cardboard sheet E produced by the double facer 20 is transferred to the rotary 21. The rotary 21 cuts the double-sided corrugated cardboard sheet E in the width direction in full width or partially in the case where the lamination is stabilized in the initial operation stage. The slitter scorer 22 cuts a wide double-sided cardboard sheet E along the transport direction so as to have a predetermined width, and processes a ruled line extending in the transport direction. The slitter scorer 22 includes a first slitter scorer unit 44 and a second slitter scorer unit 45 having substantially the same structure arranged along the conveyance direction of the double-faced cardboard sheet E. The first slitter scorer unit 44 and the second slitter scorer unit 45 have a plurality of sets of upper ruled line rolls and lower ruled line rolls arranged to face each other with the double-sided cardboard sheet E interposed therebetween, and A plurality of slitter knives arranged on the lower side are provided in the width direction.

The cut-off 23 is formed by cutting the double-sided cardboard sheet E cut in the conveying direction by the slitter scorer 22 along the width direction into a plate-like double-sided cardboard sheet F having a predetermined length. The defective product discharge device 24 discharges the double-sided corrugated cardboard sheet F determined as a defective product from the transport line. The stacker 25 stacks non-defective double-sided cardboard sheets F and discharges them as products to the outside of the machine.

Here, the paper splice detection device for corrugated cardboard according to this embodiment will be described. FIG. 2 is a schematic configuration diagram illustrating a paper splice detection device for corrugated cardboard sheets according to the present embodiment, FIG. 3 is a schematic diagram illustrating a splicer in which a mark applying device is disposed, and FIG. 4 is a diagram in which a mark detection device is disposed. FIG. 5 is a schematic diagram illustrating a preheater, a glue machine, and a double facer in which mark detection devices are arranged at different positions.

In this embodiment, as shown in FIG. 2, the cardboard sheet splice detection device 50 includes a mark application device 51, a mark detection device 52, and a control device 53. The mark imparting device 51 uses a visual agent that is not visible when a predetermined time elapses after the front liner (first liner) A, the core B, and the back liner (second liner) C are pasted together. A mark M (see FIG. 7) is given to each paper splicing portion 90 in the front liner A, the core B, and the back liner C. The mark detection device 52 detects the mark M applied by the mark applying device 51 before a predetermined time elapses. The control device 53 controls the operation timing of the mark applying device 51 based on the paper splicing information, and the operation of the defective product discharge device (sheet removal device) 24 based on the position information of the mark M detected by the mark detection device 52. Control timing.

First, the mark assigning device 51 will be described. The mark applying device 51 is provided in each of the splicers 31, 32, 33 of the mill roll stands 11, 13, 17. In addition, since the mill roll stands 11, 13, and 17 provided with the splicers 31, 32, and 33 have substantially the same configuration, here, the mark application provided on the mill roll stand 17 that processes the front liner A is provided. The device 51 will be described.

In the mill roll stand 17, as shown in FIG. 3, the stand 61 is installed at a predetermined position, and a pair of roll support arms 62a and 62b are supported on both sides thereof, and the tip ends of the roll support arms 62a and 62b. The roll papers A1 and A2 are rotatably supported by the section. The roll papers A1 and A2 are obtained by winding a front liner A having a predetermined length in a roll shape. In this case, the roll paper A1 supported by one roll support arm 62a is fed out and supplied, and the roll paper A2 supported by the other roll support arm 62b is in a splicing standby state.

The splicer 33 is configured such that a pair of introduction rolls 64a and 64b, a pair of knives 65a and 65b, and a pair of crimping bars 66a and 66b are arranged on the header 63 from below to above. In the splicer 31, a nip roll 67 and an acceleration roll 68 are disposed above the pair of crimping bars 66a and 66b. In this case, the introduction rolls 64a and 64b, the knives 65a and 65b, and the crimping bars 66a and 66b are provided so as to be close to and away from each other. A nip roll 67 is provided so as to be able to approach and separate from the acceleration roll 68. In the header 63, a dancer roll 69 and a fixed roll 70 are disposed above the nip roll 67 and the acceleration roll 68. The dancer roll 69 is movable along the horizontal direction according to the tension of the front liner A.

Therefore, when the front liner A11 is fed out from the roll paper A1, the front liner A11 passes between the introduction rolls 64a and 64b, and then passes between the knives 65a and 65b, between the crimping bars 66a and 66b, and from the acceleration roll 68. It is fed through the fixed roll 70 via the dancer roll 69. Then, when the splicer 33 performs splicing, the front liner A11 from the roll paper A1 stops feeding, and the front liner A21 fed from the standby roll paper A2 is pasted to perform splicing. Accelerate to speed.

That is, the operator first draws out the front liner A21 from the roll paper A2 and attaches it to the crimping bar 66b. Next, when the feeding speed of the front liner A21 from the roll paper A1 is decreased, the dancer roll 69 starts to move leftward in FIG. Thereafter, when the feeding of the front liner A11 from the roll paper A1 is stopped, the crimping bars 66a and 66b are brought close to each other to press the front liner A21 from the roll paper A2 and the front liner A11 from the roll paper A1 and to bond the adhesive ( Crimp with double-sided tape. Simultaneously with this operation, the knife 65a advances to cut the front liner A11 from the roll paper A1.

During this paper splicing operation, the dancer roll 69 is moved, so that the tension of the front liner A21 from the roll paper A2 is kept constant and the staying front liner A is continuously released. When the front liner A11 from the roll paper A1 is cut and the front liner A21 is fed out from the roll paper A2, the front liner A21 causes the nip roll 67 to come into contact with the acceleration roll 68 and increase the rotational speed of the acceleration roll 68. Thus, the release of the staying front liner A is completed, and the dancer roll 69 starts to move rightward in FIG. 2 and returns to the original position.

The mark applying device 51 is a spray nozzle 51a, and is provided at an intermediate position in the width direction of the front liner A, downstream of the fixed roll 70 in the splicer 33 in the transport direction of the front liner A. The spray nozzle 51a is arranged on the back surface of the front liner A at a predetermined distance, and can eject ultraviolet light emitting ink as a visualizing agent for a predetermined time. In this case, the spray nozzle 51a is a surface (rear surface) to which the core B of the front liner A is attached, and ejects ultraviolet light-emitting ink toward the center in the width direction of the front liner A. A mark M is given to the part 90. The ultraviolet light-emitting ink is ink that emits light when irradiated with ultraviolet light, and for example, 713XX059 manufactured by VALCO is used.

In the present embodiment, ultraviolet light-emitting ink is applied as a visualizing agent that is invisible when a predetermined time set in advance has elapsed. The predetermined time is the time until the mark detection device 52 detects the mark M, and the elapsed time is after the mark detection device 52 detects the mark M. That is, a predetermined time is set according to the mounting position of the mark detection device 52. Actually, it is desirable that the predetermined time elapses when the double-sided cardboard sheets F are stacked on the stacker 25 and discharged outside the apparatus.

However, the ultraviolet light-emitting ink applied in the present embodiment cannot be visually recognized unless the mark applying device 51 applies the mark M unless it is irradiated with ultraviolet light. Even such ultraviolet light-emitting ink is not visible when a predetermined time has elapsed, and thus can be applied as the visualizing agent of the present invention.

In addition, although the mark provision apparatus 51 provided in the splicer 33 of the mill roll stand 17 was demonstrated here, the same mark provision apparatus is provided also in the splicers 31 and 32 of the mill roll stands 11 and 13. FIG. The mark applying device provided on the splicer 31 of the mill roll stand 11 is a surface on which the back liner C of the center core B is not attached, and jets ultraviolet light emitting ink toward the central portion of the center core B in the width direction. By doing so, a mark is given to the paper splicing portion. Further, the mark applying device provided in the splicer 32 of the mill roll stand 13 is a surface where the inner core B of the back liner C is not attached, and the ultraviolet light emitting ink is directed toward the center in the width direction of the back liner C. A mark is given to the paper splicing part.

Next, the mark detection device 52 will be described. The mark detection device 52 is disposed between the preheater 18 and the glue machine 19. As shown in FIG. 4, the preheater 18 is configured such that preheating rolls 34, 35, and 36 are rotatably supported by a frame 71. Each preheating roll 34, 35, 36 heats the front liner A, the single-sided cardboard sheet D, and the single-sided cardboard sheet D1, and guide rolls 72a, 72b, 72c, 73a, 73b, 73c are arranged upstream in the transport direction. Are arranged, and winding angle adjusting rolls 74a, 74b, 74c are arranged on the downstream side, respectively. The winding angle adjusting rolls 74a, 74b, and 74c move in the circumferential direction of the preheating rolls 34, 35, and 36, thereby adjusting the winding angle of the front liner A, the single-sided cardboard sheet D, and the single-sided cardboard sheet D1 to preheat. The degree is adjusted.

Glue machine 19 is configured such that glue rolls 37 and 38 are rotatably supported by frame 75. The gluing rolls 37 and 38 apply the glue of the glue dams 76a and 76b to the cores B of the single-sided cardboard sheet D and the single-sided cardboard sheet D1, respectively. The gluing rolls 37 and 38 are arranged in contact with meter rolls 77a and 77b for adjusting the amount of glue adhered, and rider rolls 78a and 78b are arranged to face each other. In the double facer 20, preheaters 80 and 81 are rotatably supported by a frame 79, the front liner A is guided to the double facer 20 via the preheater 80, and the single-sided cardboard sheet D 1 is guided to the double facer 20 via the preheater 81. .

The mark detection device 52 is downstream of the preheater 18 in the transport direction of the front liner A, the core B, and the back liner C, and upstream of the glue machine 19 in the transport direction of the front liner A, the core B, and the back liner C. On the side. Therefore, the mark detection device 52 detects the mark M before the front liner A and the single-sided cardboard sheet D are bonded together.

The mark detection device 52 includes a plurality of mark detectors 52a, 52b, 52c, 52d, and 52e. Each of the mark detectors 52a, 52b, 52c, 52d, and 52e has an ultraviolet irradiation unit that irradiates ultraviolet rays and an imaging unit that images the mark N emitted by irradiating the ultraviolet rays. In this case, each of the mark detectors 52a, 52b, 52c, 52d, and 52e is configured by integrally providing the ultraviolet irradiation unit and the imaging unit, but may be configured separately.

The mark detector 52a is disposed above the front liner A traveling between the preheating roll 34 and the glue machine 19 with a predetermined gap, and detects the mark M given to the back surface of the front liner A. The mark detector 52 b is arranged with a predetermined gap below the single-sided cardboard sheet D running between the preheating roll 35 and the glue machine 19, and detects the mark M given to the core B. The mark detector 52c is disposed above the single-sided cardboard sheet D traveling between the preheating roll 35 and the glue machine 19 with a predetermined gap, and detects the mark M given to the back liner C. Further, the mark detectors 52d and 52e are arranged with a predetermined gap below and above the single-sided cardboard sheet D1 running between the preheating roll 36 and the glue machine 19, and the mark M attached to the center core B. The mark M given to the back liner C is detected.

In this case, each of the mark detectors 52b and 52d detects the mark M along a perpendicular line from the top of the stepped mountain of the core B toward the back liner C.

The position of the mark detection device 52 (mark detectors 52a, 52b, 52c, 52d, 52e) is not limited to the above-described position. For example, as shown in FIG. 5, the mark detection device 52 is located downstream of the glue machine 19 in the conveying direction of the front liner A, the center core B, and the back liner C, and from the double facer 20 to the front liner A and the center core B. And on the upstream side in the conveying direction of the back liner C.

That is, the mark detector 52 a is arranged above the front liner A traveling between the glue machine 19 and the preheater 80 with a predetermined gap, and detects the mark M given to the back surface of the front liner A. The mark detector 52b is arranged below the single-sided cardboard sheet D running between the glue machine 19 and the preheater 81 with a predetermined gap, and detects the mark M given to the core B. The mark detector 52 c is disposed above the single-sided cardboard sheet D running between the glue machine 19 and the preheater 81 with a predetermined gap, and detects the mark M given to the back liner C. The mark detectors 52d and 52e are arranged with a predetermined gap below and above the single-sided cardboard sheet D1 that travels between the glue machine 19 and the preheater 81, and the mark M provided on the core B and the back side. Each of the marks M given to the liner C is detected.

2 and 3, the control device 53 controls the operation timing of the mark applying device 51 based on the splicing information input from the splicers 31, 32, and 33. The splicing information is a splicing signal output from each of the splicers 31, 32, and 33. The splicing signal is, for example, a front spliner A11 from the roll paper A1 and a front surface from the roll paper A2 in the splicer 31. This signal is output when the knife 65a for cutting the front liner A11 is actuated after the liner A21 is bonded by actuating the pair of crimping bars 66a, 66b. The controller 53 is supplied with the conveying speed of the front liner A and the conveying distance of the front liner A from the knife 65a to the spray nozzle 51a in advance, and after the knife 65a is activated and a paper splicing signal is input, the paper The time until the splicing part 90 reaches the spray nozzle 51a is calculated. Then, the control device 53 operates the spray nozzle 51a for a predetermined time when the splicing portion 90 of the front liner A reaches the spray nozzle 51a.

In this case, the operation time (ink application time) in which the spray nozzle 51a ejects the ultraviolet light emitting ink is adjusted according to the conveying speed of the front liner A. That is, the optimal shape of the mark M formed on the front liner A is set according to the performance of the mark detection device 52, and the ultraviolet light emitting ink ejection time is set so that the mark M formed on the front liner A has the optimal shape. Adjust. Here, if the transport speed of the front liner A is increased, the ultraviolet light emitting ink ejection time by the spray nozzle 51a is shortened. If the transport speed of the front liner A is decreased, the ultraviolet light emitting ink ejection time by the spray nozzle 51a is decreased. Lengthen.

Note that here, the signal output when the knife 65a is operated is the paper splicing signal, but the signal is not limited to this signal. For example, a signal output at the time of processing relating to a paper splicing operation (when a paper splicing starts, a paper splicing operation is being performed, or a paper splicing operation is completed) such as the start of paper feeding from the roll paper A2 or the acceleration roll 68 is started. Any signal may be used. The splicing signal is not limited to an electrical signal related to the operation of the splicers 31, 32, 33, and is generated from an operation related to the splicing work regardless of the operation of the splicers 31, 32, 33. is there.

2 and 4, the control device 53 controls the operation timing of the defective product discharge device 24 based on the position information of the mark M detected by the mark detection device 52, and has a paper splicing section 90. The double-sided cardboard sheet F is removed from the conveyance line. In this case, the controller 53 determines whether the front liner A, the center core B, and the back liner C have the same speed based on the transport speed of the front liner A, the center core B, and the back liner C, and the spraying time of the ultraviolet light emitting ink from the spray nozzle 51a. The length of the mark M in the transport direction can be estimated, and the positional relationship between the paper splicing portion 90 and the mark M can be estimated. In addition, the control device 53 has input in advance the transport distance of the double-sided corrugated cardboard sheet E (F) from the mark detectors 52a, 52b, 52c, 52d, 52e to the defective product discharge device 24, and the mark detectors 52a, 52b, 52c, 52d, and 52e detect the mark M and calculate the time from when the detection signal is input until the mark M reaches the defective product discharging apparatus 24.

Therefore, the control device 53 can specify the double-sided cardboard sheet F on which the mark M is formed based on the length of the mark M detected by the mark detectors 52a, 52b, 52c, 52d, and 52e. The control device 53 operates the defective product discharge device 24 at the timing when the double-sided cardboard sheet F on which the mark M is formed arrives, and removes the double-sided cardboard sheet F having the mark M (paper splicing portion 90) from the conveyance line. In this case, the control device 53 can estimate the position of the paper splicing portion 90 from the positional relationship between the paper splicing portion 90 and the mark M, and the double-sided cardboard having only the paper splicing portion 90 regardless of the mark M. The sheet F may be removed from the conveyance line.

Here, the operation of the cardboard sheet splice detection device 50 will be described.

As shown in FIG. 1, the mill roll stand 11 is configured such that when one roll paper rotates, the core B is unwound, and when one roll paper decreases, the other roll paper starts to rotate. B is fed out, paper splicing is performed by the splicer 31, and the core B is continuously fed out from the mill roll stand 11. Further, the mill roll stand 13 is fed out by rotating one roll paper, and when one roll paper is reduced, the other liner roll is started by rotating the other roll paper. Paper splicing is performed by the splicer 32, and the back liner C is continuously fed out from the mill roll stand 13. Further, in the mill roll stand 17, when one roll paper rotates, the front liner A is fed out, and when one roll paper decreases, the other roll paper starts to rotate and the front liner A is fed out. Paper splicing is performed by the splicer 33, and the front liner A is continuously fed out from the mill roll stand 17.

In the sheet joining operation of the front liner A, as shown in FIGS. 3 and 6, the front liner A11 as the preceding sheet travels in the transport direction T1, and the front liner A21 as the succeeding sheet moves in the transport direction T2. Drive at the same speed along. At this time, the front liner A21 has a double-sided tape 91 as an adhesive affixed to the surface of the cut end portion facing the front liner A11. When the crimping bars 66a and 66b are brought close to each other and the front liner A21 and the front liner A11 are pressed against each other, the double-sided tape 91 of the front liner A21 is crimped to the attaching portion 92 of the front liner A11, and the front liner A11 and the front liner A21. Is connected. Simultaneously with this operation, when the front liner A11 is cut at the cutting position 93 by moving the knife 65a forward, a paper splicing portion 90 (see FIG. 7) is formed. Similarly, the core B and the back liner C are subjected to the paper splicing operation.

When the paper liner is completed by connecting the front liner A21 to the front liner A11, the mark applying device 51 applies the mark M to the paper joint portion 90 of the front liner A as shown in FIGS. That is, when the front liner A travels in the transport direction T, the spray nozzle 51a applies the ultraviolet light emitting ink for a predetermined time from a predetermined time before the paper splicing section 90 arrives to a predetermined time after the paper splicing section 90 passes. Erupt over. Here, the mark M1 in FIG. 7 is a current ultraviolet light emitting ink adhesion region by the spray nozzle 51a, and the mark M2 in FIG. 7 is a future ultraviolet light emitting ink adhesion region by the spray nozzle 51a. As a result, the spray nozzle 51a jets ultraviolet light-emitting ink to a region longer than the paper splicing portion 90 with respect to the surface (back surface) to which the core B of the front liner A is attached, thereby providing the mark M. The core M and the back liner C are similarly provided with a mark M on the paper splicing portion 90.

Thereafter, as shown in FIG. 4 (or FIG. 5), the core B is processed into a corrugated shape and then glued to the top of each step, and is bonded to the back liner C by a single facer 15 to form a single-sided cardboard sheet D. It is formed. After the front liner A and the single-sided cardboard sheet D (D1) are heated by the preheater 18, the mark detection device 52 detects the mark M given to the front liner A and the single-sided cardboard sheet D (D1). That is, the mark detector 52a detects the mark M given to the back surface of the traveling front liner A, and the mark detector 52b (52d) marks the mark M given to the center B in the traveling single-sided cardboard sheet D. The mark detector 52c (52e) detects the mark M given to the back liner C in the traveling single-sided cardboard sheet D. Thereafter, the front liner A and the single-sided cardboard sheet D (D1) are bonded together by a double facer 20 to form a double-sided cardboard sheet E, cut into a predetermined width by a slitter scorer 22, cut into a predetermined length by a cut-off 23, and double-sided cardboard. Sheet F is obtained.

As shown in FIGS. 2 and 8, the control device 53 operates the defective product discharge device 24 based on the position information of the marks M of the front liner A, the center core B, and the back liner C detected by the mark detection device 52. Control timing. That is, the control device 53 calculates the time for each mark M of the front liner A, the core B, and the back liner C to reach the defective product discharge device 24, and at the time when each mark M reaches the defective product discharge device 24. The defective product discharge device 24 is operated to remove the double-sided corrugated cardboard sheet F having the mark M (paper splicing portion 90) from the conveying line.

In this case, the control device 53 determines that the double-sided cardboard sheet F having the length region L1 where the mark M exists is a defective product, and operates the defective product discharge device 24 to remove it from the conveyance line. That is, even the double-faced cardboard sheet F in which the paper splicing portion 90 does not exist and only a part of the mark M exists is determined as a defective product and is removed from the transport line. However, depending on the usage pattern of the double-sided cardboard sheet F, the double-sided cardboard sheet F in which only a part of the mark M exists may be determined as a non-defective product. That is, the control device 53 determines that the double-sided cardboard sheet F having only the length region L2 where the paper splicing portion 90 exists is a defective product, and operates the defective product discharge device 24 to remove it from the conveyance line. That is, even if a part of the mark M exists, if it is a double-sided corrugated cardboard sheet F in which the paper splicing portion 90 does not exist, it is determined as a good product and is not removed from the transport line.

As a result, the double-sided cardboard sheet F shipped as a product is formed by bonding the front liner A, the corrugated core B, and the back liner C, and is invisible at one end in the length direction. The mark M formed with the ultraviolet-ray issuing ink as a visualizing agent is provided.

As described above, in the cardboard sheet splice detection device of this embodiment, when a predetermined time elapses after the front liner A, the corrugated core B, and the back liner C are pasted together. A mark imparting device 51 for imparting a mark M to each paper splicing portion 90 in the front liner A, the core B, and the back liner C using a visual invisible agent, and the mark M imparted by the mark imparting device 51 for a predetermined time. A mark detection device 52 for detecting before the passage, a mark applying device 51 and a control device 53 for controlling the mark detection device 52 are provided.

Therefore, when the mark applying device 51 applies the mark M to the front liner A, the core B, and the back liner C using the visual recognition agent, the mark detection device 52 applies the surface liner A, the core B, and the back liner C. Each mark M is detected. Here, if the double-sided cardboard sheet F having the paper splicing portion 90 detected based on the mark M is removed, the paper splicing portion 90 is not mixed into the double-sided corrugated cardboard sheet F to be a product. Further, even when the double-sided corrugated cardboard sheet F having the mark M applied by the mark applying device 51 cannot be removed, the mark M is formed of a visual invisible agent that is invisible when a predetermined time elapses. Therefore, the colored portion is not mixed in the double-sided cardboard sheet F to be a product, and as a result, the quality of the double-sided cardboard sheet F can be improved.

In the corrugated sheet joint detection device of the present embodiment, the visualizing agent is ultraviolet light emitting ink. Therefore, the mark M can be formed without coloring the front liner A, the core B, and the back liner C, and mixing of colored portions into the double-faced corrugated cardboard sheet F that is a product can be prevented.

In the cardboard sheet splice detection device according to the present embodiment, the mark detection device 52 includes an ultraviolet irradiation unit that irradiates the front liner A, the core B, and the back liner C with ultraviolet rays, and a mark that emits light by irradiating ultraviolet rays. And an imaging unit that images M. Accordingly, the ultraviolet irradiation unit irradiates ultraviolet rays toward the mark M formed of the ultraviolet light emitting ink, and the imaging unit images the mark M emitted by irradiating the ultraviolet rays, and the mark M is visualized. It can be easily detected.

In the cardboard sheet splicing part detection device of the present embodiment, the mark applying device 51 applies a mark M after paper splicing in the front liner A, the center core B, and the back liner C, and the mark detection device 52 includes the front liner A. The mark M is detected before the core B and the back liner C are bonded together. Accordingly, the front liner A, the center core B, and the back liner C are provided with the mark M after the paper splicing, and the mark M is detected before the bonding, so that the paper splicing portion 90 is accurately detected via the mark M. Can be detected.

In the cardboard sheet splice detection device according to the present embodiment, the mark applying device 51 applies the mark M to the center portion in the width direction of the front liner A, the center core B, and the back liner C. Therefore, even if the widths of the front liner A, the center core B, and the back liner C are changed, the mark M applying positions on the front liner A, the center core B, and the back liner C do not change. Position adjustment of the detection device 52 can be made unnecessary. When the width of the front liner A, the core B, and the back liner C to be conveyed is changed when the width of the cardboard sheet to be manufactured is changed, the front liner A, the core B, and the back liner C Is adjusted so that the center position is positioned at the center position in the width direction of the transport line. Therefore, even if the widths of the front liner A, the center core B, and the back liner C are changed, the mark M applying position hardly changes. The mark applying device 51 does not need to apply the mark M with high accuracy to the center in the width direction of the front liner A, the core B, and the back liner C. However, it becomes a substantially central region.

In the cardboard sheet splice detection device according to the present embodiment, the mark applying device 51 applies the mark M to the surface of the front liner A to which the core B is attached. Therefore, the mark M is not displayed on the surface of the front liner A, and even when the mark M cannot be completely removed, the mark M is displayed on the surface of the corrugated cardboard sheet as a product. There is no. Further, the surface of the cardboard sheet (the surface on which the core B of the front liner A is not attached) in a post-process (for example, printing with a box making machine or printing with a corrugator) after manufacturing the cardboard sheet. ), Since the mark M does not exist on the surface of the front liner A on which the core B is not attached, the printing failure due to the mark M does not occur.

In the cardboard sheet splice detection device of the present embodiment, the mark applying device 51 applies the mark M to the surface on which the back liner C and the core B are not attached. Therefore, the mark M is displayed on the exposed surface side of the back liner C and the core B, and the mark detection device 52 can detect the mark M with high accuracy.

In the cardboard sheet splice detection device of this embodiment, the mark detection device 52 detects the mark M along a perpendicular line from the top of the corrugation of the core B toward the back liner C. Therefore, the mark detection device 52 can accurately detect the mark M on the core B without the mark M being blocked by the steps of the core B.

In the cardboard sheet splicing part detection device of this embodiment, the control device 53 adjusts the coating time by the mark applying device 51 according to the transport speed of the front liner A, the core B, and the back liner C. Therefore, even if the conveying speed of the front liner A, the center core B, and the back liner C changes, the length of the mark M can be kept constant, and the mark detection device 52 can detect the mark M with high accuracy. At the same time, it is possible to suppress an increase in the defective length of the front liner A, the core B and the back liner C on which the mark M is formed.

In the corrugated cardboard sheet manufacturing apparatus according to the present embodiment, the splicers 31, 32, and 33 for splicing the preceding sheet and the succeeding sheet in the front liner A, the center core B, and the back liner C, and corrugated. Single facer 15 for manufacturing single-sided cardboard sheet D by bonding back liner C to core B, and front liner A for both sides of core B in single-sided cardboard sheet D manufactured by single facer 15 A double facer 20 for producing the cardboard sheet E and a defective cardboard discharge device 24 are provided.

Accordingly, the splicers 31, 32, and 33 splice the preceding sheet and the succeeding sheet in the front liner A, the center core B, and the back liner C, and the single facer 15 connects the back liner C to the corrugated core B. The double facer 20 forms a double-sided cardboard sheet E by bonding the front liner A to the core B side of the single-sided cardboard sheet D, and cuts it to a predetermined size. Corrugated cardboard sheet F is manufactured. At this time, when the mark imparting device 51 imparts the mark M to the front liner A, the core B, and the back liner C using the visual recognition agent, the mark detection device 52 is applied to the front liner A, the core B, and the back liner C. Each given mark M is detected. Here, if the double-sided cardboard sheet F having the paper splicing portion 90 detected based on the mark M is removed, the paper splicing portion 90 is not mixed into the double-sided corrugated cardboard sheet F to be a product. Further, even when the double-sided corrugated cardboard sheet F having the mark M applied by the mark applying device 51 cannot be removed, the mark M is formed of a visual invisible agent that is invisible when a predetermined time elapses. Therefore, the colored portion is not mixed in the double-sided cardboard sheet F to be a product, and as a result, the quality of the double-sided cardboard sheet F can be improved.

In the corrugated sheet manufacturing apparatus of the present embodiment, the corrugated sheet joint detection device 50 controls the operation timing of the mark applying device 51 based on the splicing signals from the splicers 31, 32, 33. Accordingly, the mark M can be accurately applied to the paper splicing portion 90 in the front liner A, the core B, and the back liner C.

In the corrugated board manufacturing apparatus of the present embodiment, the mark detection device 52 is provided on the upstream side in the conveyance direction of the single-sided corrugated board sheet D in the glue machine 19. Accordingly, since the mark detection device 52 detects the mark M before applying the paste to the center B side of the single-sided cardboard sheet D, the mark detection device 52 does not interfere with the paste and the mark on the single-sided cardboard sheet D. M can be detected with high accuracy.

In the corrugated board sheet manufacturing apparatus of the present embodiment, the mark detection device 52 is provided on the downstream side in the conveying direction of the single-sided corrugated board sheet D in the glue machine 19. Therefore, since the mark detection device 52 detects the mark M after applying glue on the core B side of the single-sided cardboard sheet D, even if the single-sided cardboard sheet D expands or contracts due to the application of glue, the mark detection device 52 The mark M on the single-sided corrugated cardboard sheet D after expansion and contraction is detected, and the mark can be detected with high accuracy.

In the corrugated cardboard sheet of the present embodiment, the double-sided corrugated cardboard sheet F in which the front liner A, the corrugated core B, and the back liner C are bonded together is formed of a visual invisible agent at the end. A mark M is provided. Therefore, even if the visual recognition material used for removing the paper splicing portion 90 remains on the double-faced corrugated cardboard sheet F, it is not visible, so that the quality of the corrugated cardboard sheet can be improved.

In the above-described embodiment, the mark applying device 51 is the spray nozzle 51a. However, the present invention is not limited to this configuration, and may be, for example, an inkjet head, an application roller, an application brush, a stamp, or the like.

In the above-described embodiment, the visualizing agent is an ultraviolet light emitting ink. However, the present invention is not limited to this configuration, and another ink may be used if it becomes invisible after a predetermined time has elapsed. Good. For example, a thermoluminescent ink that becomes visible by applying heat may be used as the visualizing agent. In this case, it is made visible by irradiating with heat just before the mark detector, and then becomes invisible after cooling for a predetermined time. Further, as the visualizing agent, it is possible to use a color erasing ink (disappearing ink) that is colored at the time of application and can be visually recognized. In this case, the mark M formed on the front liner A, the core B, and the back liner C is erased over time by using a decolorizable ink as the visualizing agent, and the double-sided cardboard sheet that becomes the product Mixing of colored portions into F can be prevented.

10 Corrugating machine (corrugated cardboard sheet manufacturing equipment)
11 Mill roll stand 12 Preheater (Preheating device)
13 Mill roll stand 14 Preheater 15 Single facer 16 Bridge 17 Mill roll stand 18 Preheater (preheater)
19 Glue Machine 20 Double Facer 21 Rotary Shader 22 Slitter Scorer 23 Cut-off 24 Defective Product Discharge Device (Sheet Removal Device)
25 Stacker 31, 32, 33 Splicer (paper splicer)
34, 35, 36 Preheating roll 37, 38 Gluing roll 50 Cardboard sheet splice detection device 51 Mark applicator 51a Spray nozzle 52 Mark detection device 52a, 52b, 52c, 52d, 52e Mark detector 53 Control device 90 Paper splicing Part 91 Double-sided tape 92 Affixing part 93 Cutting position A Front liner (first liner)
A1, A2 Roll paper A11 Front liner (previous sheet)
A21 Table liner (following sheet)
B Core (core paper)
C Back liner (second liner)
D, D1 Single-sided cardboard sheet E, F Double-sided cardboard sheet M Mark T, T1, T2 Conveying direction

Claims (15)

In a corrugated sheet joint detection device for detecting a paper joint in a corrugated sheet in which a first liner, a corrugated core paper and a second liner are bonded,
In the first liner, the core paper, and the second liner, using a visual invisible agent after a predetermined time has elapsed since the first liner, the core paper, and the second liner are pasted together. A mark applying device for applying a mark to each paper splice,
A mark detection device for detecting the mark applied by the mark application device before the predetermined time has elapsed;
An apparatus for detecting a spliced portion of a corrugated cardboard sheet. 2. The paper splice detection device for corrugated cardboard sheets according to claim 1, wherein the visual recognition agent is an ultraviolet light emitting ink. The mark detection device includes an ultraviolet irradiation unit that irradiates the first liner, the core paper, and the second liner with ultraviolet rays, and an imaging unit that captures the mark emitted by irradiating the ultraviolet rays. The paper splice detection device for corrugated cardboard sheets according to claim 2. The corrugated sheet joint detection device according to claim 1, wherein the visualizing agent is a decolorizable ink. The mark applying device applies a mark after splicing in the first liner, the core paper, and the second liner, and the mark detection device is configured to apply the mark before the first liner and the core paper are pasted together. 5. The paper splice detection device for corrugated cardboard sheets according to claim 1, wherein the mark is detected. The said mark provision apparatus provides a mark to the center part of the width direction in the said 1st liner, the said core paper, and the said 2nd liner, The Claim 1 characterized by the above-mentioned. Cardboard sheet splice detection device. The corrugated cardboard sheet splicing unit according to any one of claims 1 to 6, wherein the mark imparting device imparts a mark to a surface of the first liner to which the core paper is pasted. Detection device. The corrugated cardboard sheet splicing according to any one of claims 1 to 7, wherein the mark imparting device imparts a mark to a surface on which the second liner and the core paper are not attached. Part detection device. The corrugated cardboard splice detection device according to claim 8, wherein the mark detection device detects the mark along a perpendicular line from the top of the corrugated step of the core paper toward the second liner. A control device for controlling the mark applying device is provided, and the mark applying device is configured to apply the mark to the first liner, the core paper, and the second liner by coating, The corrugated sheet according to any one of claims 1 to 9, wherein a coating time by the mark applying device is adjusted according to a conveying speed of the first liner, the core paper, and the second liner. Paper splice detection device. A splicing device for splicing the preceding sheet and the succeeding sheet in the first liner, the core paper, and the second liner;
A single facer for producing a single-sided cardboard sheet by laminating a second liner to a corrugated core paper;
A double facer for producing a double-sided cardboard sheet by bonding a first liner to the core paper side of the single-sided cardboard sheet;
A paper splice detection device for corrugated cardboard sheets according to any one of claims 1 to 10,
A sheet removing device for removing the paper spliced portion detected by the paper spliced portion detecting device of the corrugated cardboard sheet from a conveying line;
An apparatus for manufacturing a corrugated cardboard sheet. 12. The corrugated cardboard sheet producing apparatus according to claim 11, wherein the corrugated sheet joint detecting device controls the operation timing of the mark applying device based on a paper splicing signal from the splicing device. The glue machine which applies paste to the core paper side of the single-sided cardboard sheet is provided, and the mark detection device is provided upstream in the conveyance direction of the single-sided cardboard sheet in the glue machine. An apparatus for producing a corrugated cardboard sheet according to claim 11 or claim 12. The glue machine which applies paste to the core paper side of the single-sided cardboard sheet is provided, and the mark detection device is provided downstream in the conveyance direction of the single-sided cardboard sheet in the glue machine. An apparatus for producing a corrugated cardboard sheet according to claim 11 or claim 12. In the corrugated cardboard sheet in which the first liner, the corrugated core paper, and the second liner are bonded together,
A mark formed of a visual invisible agent is provided at the end,
A cardboard sheet characterized by that.

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