Corrugated sheet feeder

Abstract

To continuously supply a long corrugated cardboard sheet to a corrugated cardboard blank manufacturing device for a long time without stopping the corrugated cardboard blank manufacturing device.SOLUTION: A corrugated cardboard sheet feeding device 10 according to the present invention includes: a transfer device 20 for a bellows-shaped corrugated cardboard stacked sheet body 60; a feeding section 40 for a long corrugated cardboard sheet 61 pulled out from the bellows-shaped corrugated cardboard stacked sheet body 60; and a control section 21 for controlling operations thereof. The transfer device 20 replenishes the bellows-shaped corrugated cardboard stacked sheet body 60 at a send-out position where the long corrugated cardboard sheet 61 drawn from the bellows-shaped corrugated cardboard stacked sheet body 60 is delivered toward a corrugated cardboard blank manufacturing device 50.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a cardboard sheet delivery device that delivers long cardboard sheets from a bellows-shaped cardboard sheet stack in which long cardboard sheets are folded into a bellows shape and stored, to a cardboard blank manufacturing device, and to a bellows-shaped cardboard sheet stack replenishing device that replenishes the cardboard sheet delivery device with the bellows-shaped cardboard sheet stack. [Background technology]

[0002] Corrugated cardboard boxes are manufactured by folding and assembling blanks cut into a specific shape from corrugated cardboard sheets, and come in a variety of types, from standard shapes with standard length, width, and height, to irregular shapes. Corrugated cardboard blanks are usually manufactured by cutting out a single plate-shaped corrugated cardboard sheet and slitting and scoring where necessary. When manufacturing corrugated cardboard blanks to manufacture standard-shaped corrugated cardboard boxes, cutting out a set length and slitting and scoring at set locations can be carried out continuously and at high speed, making it possible to produce large quantities of corrugated cardboard blanks at low cost.

[0003] On the other hand, in recent years, there has been an increasing demand for on-demand corrugated cardboard box production, whereby corrugated cardboard boxes of different sizes can be produced individually to accommodate a variety of packaged items. In such cases, if corrugated cardboard blanks of various unfolded shapes were produced from a plate-shaped corrugated cardboard sheet of a fixed size, a lot of cutting waste would occur.

[0004] Therefore, a device has been proposed in which long cardboard sheets are manufactured and stored in advance, and when necessary, only the required length is pulled out and a cardboard blank corresponding to a desired size of cardboard box is cut out (for example, see Patent Document 1). This cardboard blank manufacturing device includes a conveying device that pulls out and conveys a stocked long cardboard sheet little by little, a cross-cutting device that makes a cut in a direction perpendicular to the conveying direction, and a vertical cutting device that makes a cut along the conveying direction, and the vertical cutting device is movable in the width direction (direction perpendicular to the conveying direction). The long cardboard sheet pulled out from the stock is first cut to the required length by the cross-cutting device, and then cuts and slits are made at appropriate places by the cross-cutting device and the vertical cutting device to manufacture a cardboard blank of the required shape and size. In many cases, creases are also made at appropriate places.

[0005] In such on-demand corrugated cardboard box production, it has been proposed to fold the continuously produced double-sided corrugated cardboard into an accordion shape, store it in that state, and use it in the above-mentioned on-demand corrugated cardboard box production (for example, see Non-Patent Document 1). By folding it into an accordion shape in this way, both double-sided and single-sided corrugated cardboard can be stored as long corrugated cardboard sheets. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] International Publication No. WO2014 / 119439 [Non-patent literature]

[0007] [Non-Patent Document 1] BOX ON DEMAND MACHINE, Panotec Srl, [Retrieved March 11, 2020], Internet<URL:http: / / http: / / www.boxondemand.jp / en / box-on-demand-machines / > Summary of the Invention [Problem to be solved by the invention]

[0008] When cardboard blanks are cut out one by one from the front end side of one long cardboard sheet folded in an accordion shape, and the length of the remaining long cardboard sheet does not meet the length required for the desired cardboard blank, it is necessary to replenish the long cardboard sheet with a new one. In the case of a long cardboard sheet folded in an accordion shape, the long cardboard sheet is stored in the state of a bellows-shaped cardboard sheet stack in which the long cardboard sheet is stacked vertically by folding in an accordion shape. Therefore, a new bellows-shaped cardboard sheet stack is replenished to the device. When performing such an operation, it is necessary to temporarily stop the cardboard blank manufacturing device, which reduces the manufacturing efficiency of the cardboard blank and requires extra manual work. Therefore, it is considered to connect the front end of a new long cardboard sheet to the rear end of the long cardboard sheet sent to the cardboard blank manufacturing device.

[0009] When the long corrugated cardboard sheets are fed from the bellows-shaped corrugated cardboard sheet stack to the corrugated cardboard blank manufacturing device, the feeding device lifts the long corrugated cardboard sheets from the upper layer of the bellows-shaped corrugated cardboard sheet stack to a higher position. Therefore, when the remaining bellows-shaped corrugated cardboard sheet stack is removed from the feeding position and a refill bellows-shaped corrugated cardboard sheet stack is placed at the feeding position, if the distance between the refill bellows-shaped corrugated cardboard sheet stack and the feeding device becomes far, the long corrugated cardboard sheets connected as described above may bend under their own weight, causing a delay in feeding the long corrugated cardboard sheets.

[0010] An object of the present invention is to continuously replenish long cardboard sheets without stopping a cardboard blank manufacturing device. [Means for solving the problem]

[0011] The present invention, which has been made to solve the above problems, A cardboard sheet delivery device that delivers long cardboard sheets from a bellows-shaped cardboard sheet stack in which long cardboard sheets are folded into a bellows shape at predetermined lengths to a cardboard blank manufacturing device, A delivery sensor detects whether the long cardboard sheet is being delivered to the cardboard blank manufacturing device from the bellows-shaped cardboard sheet stack arranged at a predetermined delivery position; a stack detection sensor for detecting whether the accordion-shaped cardboard sheet stack is present at the delivery position; A transfer device for transferring the accordion-shaped corrugated cardboard sheet stack arranged at a predetermined preparation position to the delivery position; A control unit that transfers the bellows-shaped cardboard sheet stack arranged at the preparation position to the delivery position by the transfer device when the stack detection sensor detects that the bellows-shaped cardboard sheet stack is not present at the delivery position; The present invention is characterized by comprising:

[0012] According to the present invention, the use status of the bellows-shaped cardboard sheet stack placed at the sending position is monitored by the stack detection sensor, so that the refilling operation of transferring the bellows-shaped cardboard sheet stack placed at the preparation position to the sending position can be performed at an appropriate timing. The front end of the long cardboard sheet of the refill bellows-shaped cardboard sheet stack placed at the preparation position is connected in advance to the rear end of the long cardboard sheet of the bellows-shaped cardboard sheet stack in use placed at the sending position, so that the long cardboard sheet can be continuously sent to the cardboard blank manufacturing device. Furthermore, by placing a plurality of bellows-shaped cardboard sheet stacks at the preparation position and keeping the rear end of the long cardboard sheet connected to the front end of the long cardboard sheet of the following bellows-shaped cardboard sheet stack, it is possible to continuously supply the long cardboard sheet to the cardboard blank manufacturing device for a long period of time.

[0013] In addition, it is preferable that the control unit of the cardboard sheet feeding device of the present invention transfers the accordion-shaped cardboard sheet stack arranged at the preparation position to the feeding position by the transfer device when the stack detection sensor detects that the accordion-shaped cardboard sheet stack is not present at the feeding position and the feeding sensor detects that the long cardboard sheet is being fed to the cardboard blank manufacturing device.

[0014] When the sending sensor detects that the long cardboard sheet is being sent to the cardboard blank manufacturing device, i.e., when the sending of the long cardboard sheet to the cardboard blank manufacturing device is being executed, the control unit moves the bellows-shaped cardboard sheet stack arranged at the preparation position to the sending position, thereby preventing the long cardboard sheet from sagging due to its own weight when the bellows-shaped cardboard sheet stack is replenished, and enabling the long cardboard sheet to be sent to the cardboard blank manufacturing device smoothly. This reduces the decrease in the manufacturing efficiency of the cardboard blanks caused by stopping the cardboard blank manufacturing device.

[0015] The transfer device of the cardboard sheet feeding device of the present invention is preferably equipped with a pallet conveying mechanism that places a bellows-shaped cardboard sheet stack on a pallet and conveys it, and the stack detection sensor is preferably a first sensor that detects the presence of the bellows-shaped cardboard sheet stack on the pallet at the feeding position.

[0016] The pallet conveying mechanism allows the smooth movement of a heavy bellows-shaped laminate of corrugated cardboard sheets. As such a pallet conveying mechanism, a so-called roller conveyor having a plurality of rollers that rotate while in contact with the lower surface of the pallet due to the operation of a driving source can be adopted. The plurality of rollers that rotate due to the operation of a driving source do not need to be individually connected to the driving source, and include, for example, a case in which at least one of the plurality of rollers is a driving roller and the plurality of rollers are connected to an endless chain or an endless belt so as to rotate synchronously. The driving source of the plurality of rollers may be a driving pulley around which an endless chain or an endless belt is wound. The driving roller and the driving pulley may have a built-in motor, or their rotation shafts may be connected to a separate motor.

[0017] In addition, when the first sensor detects that the bellows-shaped corrugated cardboard sheet stack is not present on the pallet, the control unit can control the pallet transport mechanism to transport the bellows-shaped corrugated cardboard sheet stack arranged at the preparation position to the sending position in accordance with the end of use of the bellows-shaped corrugated cardboard sheet stack. Here, when the first sensor detects that the bellows-shaped corrugated cardboard sheet stack is not present on the pallet, the control unit includes a time from when the first sensor detects that the bellows-shaped corrugated cardboard sheet stack is not present on the pallet until a predetermined time has elapsed. Note that the predetermined time includes a time until the empty pallet is discharged from the sending position, etc.

[0018] The cardboard sheet feeding device according to the present invention further includes a second sensor for detecting whether a pallet is present at the feeding position when the cardboard sheet feeding device includes the first sensor, It is preferable that the control unit transfers the accordion-shaped cardboard sheet stack arranged at the preparation position to the discharge position by the transfer device when the first sensor detects that the accordion-shaped cardboard sheet stack is not present and the second sensor detects that a pallet is not present at the discharge position.

[0019] The control unit moves the pallet carrying the accordion-shaped cardboard sheet stack when the second sensor detects that no pallet is present at the discharge position, thereby avoiding the device from stopping due to collisions between pallets.

[0020] The sensor that detects the absence of a pallet at the sending position may be a third sensor that detects that a pallet has passed through a conveying path that is discharged from the sending position and headed for a collection position where the empty pallet is collected.

[0021] The cardboard sheet delivery device according to the present invention includes a rotating body that delivers the long cardboard sheet from the bellows-shaped cardboard sheet stack arranged at the delivery position to the cardboard blank manufacturing device; It is preferable that the rotating body be rotatably supported at a position higher than the height of the bellows-shaped cardboard sheet stack.

[0022] The rotating body, supported at a position higher than the height of the accordion-shaped cardboard sheet stack, rotates while abutting against the back surface of the long cardboard sheet, thereby making it possible to smoothly pull out the long cardboard sheet from the upper layer of the accordion-shaped cardboard sheet stack in which the long cardboard sheets are stacked in the vertical direction, and to smoothly feed the long cardboard sheet to the cardboard blank manufacturing device.

[0023] The rotating body preferably has a cross-sectional shape of a regular polygon, and the length of one side of the regular polygon is equivalent to the predetermined length of the bellows-shaped cardboard sheet stack. The regular polygon may be an equilateral triangle, a square, or the like, as long as the length of one side corresponds to the pitch (predetermined length) of the stacking creases of the long cardboard sheets. By matching the corners of the regular polygon with the pitch of the stacking creases, the contact state between the rotating body and the back surface of the long cardboard sheets is stabilized, and the long cardboard sheets can be reliably pulled out from the bellows-shaped cardboard sheet stack, and the long cardboard sheets can be smoothly sent to the cardboard blank manufacturing device.

[0024] The rotating body may rotate following the transport of the long cardboard sheet in the cardboard blank manufacturing device, or the transport device may be operated under the control of the control unit of the cardboard sheet delivery device of the present invention, and rotated in conjunction with the transport of the long cardboard sheet in the cardboard blank manufacturing device. By matching the rotation speed of the rotating body with the transport speed of the long cardboard sheet in the cardboard blank manufacturing device, the long cardboard sheet can be smoothly delivered to the cardboard blank manufacturing device. The delivery sensor that detects whether the long cardboard sheet is being delivered to the cardboard blank manufacturing device may be a rotation sensor that detects the rotation of the rotating body.

[0025] The bellows-shaped cardboard sheet stack replenished by the cardboard sheet delivery device preferably comprises a bellows stack section in which long cardboard sheets are folded into a bellows shape at predetermined lengths, and a joint section which is an extending portion from the end of the long cardboard sheet in the bottom layer of the bellows stack section and protrudes from the bellows stack section.

[0026] A plurality of bellows-shaped corrugated cardboard sheet stacks can be smoothly connected by joining the front end of a long corrugated cardboard sheet pulled out from the upper layer of the bellows laminate of another (rear) bellows-shaped corrugated cardboard sheet stack to the joint portion of the long corrugated cardboard sheet being used in the corrugated cardboard blank manufacturing device. The connection between the ends of the long corrugated cardboard sheets of different bellows-shaped corrugated cardboard sheet stacks may be performed manually or automatically using a joining device.

[0027] In addition, it is preferable that the long cardboard sheet has an auxiliary crease parallel to the lamination crease for assisting the connection between the end of the joint part of the bellows-shaped cardboard sheet laminate arranged at the sending position and the end of the top layer of the bellows laminate part of the bellows-shaped cardboard sheet laminate arranged at the preparation position. The connection between the multiple bellows-shaped cardboard sheet laminates may be made by gluing the surfaces of the ends of the long cardboard sheets together, or may be made by using a member that assists the connection.

[0028] When manually connecting the long cardboard sheets of a plurality of bellows-shaped cardboard sheet stacks arranged at the sending position and the preparation position, the long cardboard sheet of the top layer of the other bellows-shaped cardboard sheet (rear side) is pulled out toward the joint part of the bottom layer of one bellows-shaped cardboard sheet (front side), but this operation can be performed smoothly by providing an auxiliary fold line. Note that this auxiliary fold line may be provided on the long cardboard sheets of the topmost 2-3 layers of the bellows-shaped cardboard sheet in the unused bellows-shaped cardboard sheet stack, taking into consideration the height of the bellows-shaped cardboard sheet and the length of the joint part.

[0029] In addition, when the end of the joint portion is joined to the end of the top long cardboard sheet of the bellows laminate of another (rear) bellows-shaped cardboard sheet laminate by butting the end faces together, it is preferable that the sum of the length of the joint portion and the length from the end of the top long cardboard sheet of the bellows laminate to the nearest stacking fold line of each bellows-shaped cardboard sheet laminate is a specified length.

[0030] When the end of the joint portion is butted against the end faces (cut surfaces) of the ends of the long cardboard sheets in the top layer of the bellows laminate of another (rear) bellows-shaped cardboard sheet laminate, the predetermined length, i.e., the pitch of the lamination creases, is maintained even in the layer where the long cardboard sheets have a seam. This allows the long cardboard sheets to be smoothly fed to the cardboard blank manufacturing device regardless of the presence or absence of a seam.

[0031] In addition, the present invention, which has been made to solve the above problems, A bellows-shaped corrugated cardboard sheet stack replenishing device that replenishing a bellows-shaped corrugated cardboard sheet stack, in which a long corrugated cardboard sheet is folded into a bellows-shaped shape at predetermined intervals, to a cardboard delivery device, a stack detection sensor for detecting whether the bellows-shaped cardboard sheet stack is present at a predetermined delivery position; A transfer device for transferring the accordion-shaped corrugated cardboard sheet stack arranged at a predetermined preparation position to the delivery position; A control unit that transfers the bellows-shaped cardboard sheet stack arranged at the preparation position to the delivery position by the transfer device when the stack detection sensor detects that the bellows-shaped cardboard sheet stack is not present at the delivery position; The present invention is characterized by comprising: Effect of the Invention

[0032] By using the cardboard sheet replenishing device according to the present invention, it is possible to continuously supply long cardboard sheets to the cardboard blank manufacturing device for a long period of time without stopping the cardboard blank manufacturing device. [Brief description of the drawings]

[0033] [Figure 1] 1 is a schematic side view of a cardboard sheet feeding device according to an embodiment of the present invention; [Diagram 2] 1 is a schematic plan view of a cardboard sheet feeding device according to an embodiment of the present invention; [Diagram 3] FIG. 2 is a block diagram showing a main control system of the cardboard sheet feeding device according to the embodiment of the present invention. [Figure 4] 1 is an overall view of a bellows-shaped cardboard sheet stack being replenished by a transfer device of a cardboard sheet delivery device according to an embodiment of the present invention; [Diagram 5] FIG. 5 is a diagram showing the connection between the accordion-shaped cardboard sheet stacks shown in FIG. 4. [Figure 6] FIG. 5 is a diagram showing the connection between the accordion-shaped cardboard sheet stacks shown in FIG. 4. [Figure 7] 11A and 11B are diagrams illustrating the replenishing operation of a bellows-shaped cardboard sheet stack by a transfer device of a cardboard sheet feeding device according to an embodiment of the present invention. [Figure 8] 11A and 11B are diagrams illustrating the replenishing operation of a bellows-shaped cardboard sheet stack by a transfer device of a cardboard sheet feeding device according to an embodiment of the present invention. [Figure 9] 11A and 11B are diagrams illustrating the replenishing operation of a bellows-shaped cardboard sheet stack by a transfer device of a cardboard sheet feeding device according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0034] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0035] <1. Configuration> Fig. 1 is a schematic side view of a cardboard sheet delivery device 10 according to an embodiment of the present invention, and Fig. 2 is a schematic plan view thereof. Fig. 3 is a block diagram showing a main control system of the cardboard sheet delivery device 10 according to an embodiment of the present invention.

[0036] The cardboard sheet delivery device 10 according to the present embodiment pulls out a long cardboard sheet 61 from a bellows-shaped cardboard sheet stack 60 in which the long cardboard sheet 61 is folded into a bellows shape at predetermined lengths, and delivers it to a cardboard blank manufacturing device 50. The long cardboard sheet 61 delivered by the cardboard sheet delivery device 10 is conveyed to a cardboard blank manufacturing unit (not shown) by a conveying unit 53 of the cardboard blank manufacturing device 50, and a cardboard blank is cut out from the long cardboard sheet 61. When the cardboard blank is cut out, the conveying unit 53 temporarily stops conveying the long cardboard sheet 61, so that the conveying of the long cardboard sheet 61 is performed intermittently in accordance with the timing of cutting out while maintaining a predetermined conveying speed. The cardboard blank manufacturing device 50 is connected to a control unit 51 that controls these operations, and a control panel 52 that accepts various inputs to the control unit 51 from a user. The cardboard blanks cut out by the cardboard blank manufacturing device 50 are then assembled into a cardboard box manually or by an assembly device.

[0037] This cardboard sheet feeding device 10 includes a transfer device 20 for a bellows-shaped cardboard sheet stack 60, a feeding section 40 for a long cardboard sheet 61 pulled out from the bellows-shaped cardboard sheet stack 60, a control section 21 for controlling the operation of these components, and a control panel 22 for accepting various inputs to the control section 21 from a user.

[0038] The transfer device 20 replenishes the bellows-shaped cardboard sheet stack 60 at a delivery position 31 where the long cardboard sheet 61 pulled out from the bellows-shaped cardboard sheet stack 60 is delivered toward the cardboard blank manufacturing device 50. The transfer device 20 supports a plurality of bellows-shaped cardboard sheet stacks 60 so that they can be transported, and transports the bellows-shaped cardboard sheet stacks 60 along a transport path toward the delivery position 31.

[0039] The transfer device 20 includes a pair of roller conveyors 24 that form a conveying path for the bellows-shaped cardboard sheet stack 60 placed on the pallet P. The roller conveyor 24 includes a plurality of conveying rollers, and constitutes a pallet conveying mechanism that rotates using the drive rollers 23 arranged at a predetermined interval as a driving source. The plurality of conveying rollers are connected to one of the drive rollers 23 by a chain belt (not shown) and rotate in synchronization with the rotation of the drive roller 23. The bellows-shaped cardboard sheet stack 60 placed on the pallet P is transferred toward the sending position 31 by the conveying rollers rotating while in contact with the lower surface of the pallet P. As shown by the dashed line in FIG. 2, the downstream side of the conveying path in the transfer device 20 closest to the sending section 40 is the sending position 31 where the long cardboard sheet 61 is sent toward the cardboard blank manufacturing device 50 by the operation of the sending section 40, and the upstream side is the preparation position 32.

[0040] At the intermediate position between the pair of roller conveyors 24, a plurality of free rollers 25 are arranged in parallel with the roller conveyors 24 to assist the movement of the bellows-shaped cardboard sheet laminate 60. Between the delivery position 31 and the preparation position 32 on the conveying path, a tiltable rod member (not shown) is provided to regulate the movement of the bellows-shaped cardboard sheet laminate 60. Note that other members may be used to regulate the movement of the bellows-shaped cardboard sheet laminate 60. For example, a plate member that is raised and lowered by an air cylinder may be arranged between the pair of roller conveyors 24. In this case, the movement of the bellows-shaped cardboard sheet laminate 60 is regulated by raising the plate member to a position higher than the height at which the conveying rollers contact the lower surface of the pallet P.

[0041] The transfer device 20 includes a second conveying path for discharging the pallet P that has become empty by pulling out all the long cardboard sheets 61 from the bellows-shaped cardboard sheet stack 60 at the sending-out position 31. The second conveying path is configured by a pair of guide rails 28 extending from the sending-out position 31 in a direction perpendicular to the conveying direction of the bellows-shaped cardboard sheet stack 60. In this embodiment, the pallet P on which the bellows-shaped cardboard sheet stack 60 is placed is made of cardboard, and the weight of the pallet P is light. Therefore, by pushing the pallet P toward the second conveying path by a discharging member (not shown), the pallet P slides along the guide rails 28 toward the recovery position 33 downstream of the second conveying path. The pallet P may be discharged to an empty space below the sending-out section 40. In this case, the control unit 21 may control the operation of the drive roller 23 at a position corresponding to the sending-out position 31 to discharge the empty pallet P.

[0042] This cardboard sheet delivery device 10 includes a first sensor 35 as a stack detection sensor that detects the presence of the bellows-shaped cardboard sheet stack 60 at the delivery position 31. The first sensor 35 is disposed at a predetermined height position facing the delivery position 31, detects the presence or absence of the long cardboard sheet 61 that forms the bellows-shaped cardboard sheet stack 60 on the pallet P, and transmits the detection result to the control unit 21.

[0043] In addition, this cardboard sheet feeding device 10 is equipped with a second sensor 36 that detects whether or not a pallet P is present at the feeding position 31. The second sensor 36 is disposed in a position facing the side of the pallet P at the feeding position 31, detects the presence or absence of the pallet P at the feeding position 31, and transmits the detection result to the control unit 21.

[0044] Furthermore, this cardboard sheet feeding device 10 includes a third sensor 37 that detects that the pallet P has passed through the second transport path that is discharged from the sending position 31 and heads toward the recovery position 33 where the empty pallet P is recovered. The third sensor 37 is disposed at any position on the way to the recovery position 33 in a position facing the second transport path, detects that the pallet P has passed through, and transmits the detection result to the control unit 21. Note that the first sensor 35, second sensor 36, and third sensor 37 may be photoelectric sensors equipped with a light receiving unit and a light emitting unit, or the like.

[0045] The delivery section 40 includes a rotor 41 and a support frame 42 that rotatably supports the rotor 41. The rotor 41 rotates about a rotation axis 43 to deliver the long cardboard sheet 61 from the delivery position 31 to the cardboard blank manufacturing device 50. The rotor 41 has a cross-sectional shape of an equilateral triangle, and the length of one side of the equilateral triangle is a predetermined length in the bellows-shaped cardboard sheet stack 60, i.e., a length corresponding to the pitch of the stacking creases when the long cardboard sheet 61 is folded in an accordion-like shape.

[0046] A rotation sensor 44 for detecting the rotation state of the rotating body 41 is attached to the rotating shaft 43 of the rotating body 41. This rotation sensor 44 functions as a sending sensor for detecting whether or not the long cardboard sheet 61 is sent out from the bellows-shaped cardboard sheet stack 60 arranged at the sending position 31 to the cardboard blank manufacturing device 50. For example, a sensor for measuring the amount of rotation such as a rotary encoder can be adopted as the rotation sensor 44. In this embodiment, the rotation sensor 44 of the rotating body 41 is the sending sensor, but is not limited thereto. That is, the sending sensor may be a sensor for monitoring the conveying status of the long cardboard sheet 61 in the conveying section 53 on the cardboard blank manufacturing device 50 side. In this case, the control section 21 of the cardboard sheet sending device 10 may determine whether or not the long cardboard sheet 61 is sent out to the cardboard blank manufacturing device 50 by inputting a signal indicating that the long cardboard sheet 61 is being conveyed, which is transmitted from the control section 51 on the cardboard blank manufacturing device 50 side.

[0047] In addition, in this embodiment, the rotor 41 has a cross-sectional shape of an equilateral triangle, but the cross-sectional shape may be a square, a regular pentagon, or the like. It is sufficient that the shape is a regular polygon whose side length corresponds to the pitch of the stacking fold lines of the long cardboard sheets 61. The rotor 41 is a frame structure made up of radial frame members that extend radially toward the apexes of an equilateral triangle attached to the rotating shaft 43, and parallel frame members that are parallel to the rotating shaft 43 and connect the tips of the radial frame members.

[0048] The support frame 42 rotatably supports the rotor 41 at a position higher than the height of the bellows-shaped cardboard sheet stack 60 with the axial direction of the rotation shaft 43 perpendicular to the conveying direction of the long cardboard sheet 61, and is provided with a bearing portion for receiving the rotation shaft 43 of the rotor 41. Note that the rotor 41 is preferably located close to the delivery position 31 so as not to cause deflection of the drawn-out long cardboard sheet 61 due to its own weight, and the height of the rotor 41 is adjusted taking into consideration the height at which the rotating rotor 41 does not interfere with the top layer of the unused bellows-shaped cardboard sheet stack 60.

[0049] <2. Connection of accordion-shaped corrugated cardboard sheet laminates> Fig. 4 is an overall view of a bellows-shaped corrugated cardboard sheet stack 60 replenished by the transfer device 20 of the corrugated cardboard sheet delivery device 10 according to an embodiment of the present invention. Figs. 5 and 6 are views showing the connection between the bellows-shaped corrugated cardboard sheet stacks 60 shown in Fig. 4. Fig. 5 shows a state before the connection between a joint part 62 of one of the two bellows-shaped corrugated cardboard stacks and an end of the top long corrugated cardboard sheet 61 of the bellows stack part 63 of the other, and Fig. 6 shows a state after the connection. Note that in Figs. 5 and 6, the conveying path of the transfer device 20 is omitted.

[0050] The bellows-shaped cardboard sheet laminate 60 includes a bellows laminated portion 63 in which long cardboard sheets 61 are folded and laminated in a bellows shape at predetermined lengths, and a joint portion 62 that is an extending portion from an end of the long cardboard sheet 61 at the bottom layer of the bellows laminated portion 63 and protrudes from the bellows laminated portion 63. Usually, the bellows-shaped cardboard sheet laminate 60 is stored with one pallet P on it.

[0051] In the bellows-shaped cardboard sheet laminate 60, the sum of the joint length L1, which is the length of the joint portion 62, and the top layer length L3, which is the length from the end of the top long cardboard sheet 61 of the bellows laminated portion 63 to the nearest stacking crease, is a predetermined length, that is, the same length as the stacking crease interval L2 from the stacking crease to the stacking crease of the bellows laminated portion 63 (L1+L3=L2). When the end face (cut surface) of the end 64 of the joint portion 62 of the bellows-shaped cardboard sheet laminate 60 arranged at the sending position 31 and the end face (cut surface) of the end 65 of the top long cardboard sheet 61 of the bellows laminated portion 63 of the bellows-shaped cardboard sheet laminate 60 arranged at the preparation position 32 are butted against each other, and the two are joined together, for example, with adhesive tape, the pitch of the stacking creases is maintained even in the layer with the joint of the long cardboard sheet 61. This prevents the rotor 41 from halting the sending out.

[0052] A plurality of bellows-shaped cardboard sheet laminates 60 can be kept waiting on the conveying path of the transfer device 20. When replenishing the conveying path with a new bellows-shaped cardboard sheet laminate 60, the user may pull out and hang down a long cardboard sheet 61 having a length (approximately two layers from the top layer) equivalent to the height L4 of the bellows laminated portion 63 of the new bellows-shaped cardboard sheet laminate 60 in advance, or may bring the replenishing bellows-shaped cardboard sheet laminate 60 close to the bellows-shaped cardboard sheet laminate 60 to be connected, and then pull out the long cardboard sheet 61 from the top layer of the bellows laminated portion 63 and hang down.

[0053] In addition, the end 64 of the joint portion 62 of the bellows-shaped cardboard sheet stack 60 arranged at the delivery position 31 or at the preparation position 32 closer to the delivery position 31 in the conveying path of the transfer device 20 and the end 65 of the top long cardboard sheet 61 of the bellows laminated portion 63 of the subsequent bellows-shaped cardboard sheet stack 60 can be connected using double-sided tape, adhesive, staples, tacks, etc. The end 64 of the joint portion 62 and the end 65 of the top long cardboard sheet 61 may be connected manually or automatically using an appropriate connecting device. Whatever the connecting method, it is only necessary that the pitch of the stacking creases is maintained in the layer with the joint of the long cardboard sheet 61 when the end 64 of the joint portion 62 and the end 65 of the top long cardboard sheet 61 of the bellows laminated portion 63 are connected.

[0054] In addition to the lamination fold lines 66, the bellows-shaped cardboard sheet laminate 60 has auxiliary fold lines 67 that are parallel to the lamination fold lines 66 and assist in connecting the lamination lines 62 (FIG. 5). The auxiliary fold lines 67 do not need to be provided in all layers of the bellows laminate 63, and may be provided in, for example, the top two or three layers of the unused bellows-shaped cardboard sheet laminate 60.

[0055] By providing the auxiliary creases 67 at a pitch shorter than the pitch of the lamination creases 66, even if the space between the accordion-shaped corrugated cardboard sheet stacks 60 is narrow, the worker can easily manually pull down the long corrugated cardboard sheet 61 from the top layer of the accordion-shaped laminated portion 63 of the following accordion-shaped corrugated cardboard sheet stack 60 (FIG. 6). In this way, the connection between the accordion-shaped corrugated cardboard sheet stack 60 arranged at the sending position 31 and the accordion-shaped corrugated cardboard sheet stack 60 arranged at the preparation position 32, and the connection between the multiple accordion-shaped corrugated cardboard sheet stacks 60 arranged at the preparation position 32 can be made more efficient. The auxiliary creases 67 are preferably provided at a position half the pitch of the lamination creases 66. Furthermore, if half the width of the adhesive tape is attached to the joint portion 62 side in advance across the width of the long corrugated cardboard sheet 61, the manual connection work can be made more efficient.

[0056] <3. Replenishment operation> 7 to 9 are diagrams illustrating the replenishing operation of the bellows-shaped cardboard sheet stack 60 by the transfer device 20 of the cardboard sheet delivery device 10 according to the embodiment of the present invention. Fig. 7 shows a state in which an empty pallet P is discharged from the delivery position 31, and Fig. 8 shows a state in which the bellows-shaped cardboard sheet stack 60 at the preparation position 32 is in the middle of being transferred toward the delivery position 31. And Fig. 9 shows a state in which the arrangement of the bellows-shaped cardboard sheet stack 60 at the delivery position 31 has been completed.

[0057] When the detection result transmitted from the first sensor 35 becomes an input indicating that the bellows-shaped cardboard sheet stack 60 on the pallet P at the sending-out position 31 is "absent," the control unit 21 operates the discharging member of the pallet P to discharge the empty pallet P to the second conveying path. Next, when the detection result transmitted from the second sensor 36 becomes an input indicating that the pallet P is not present at the sending-out position 31, the control unit 21 drives the driving roller 23 of the roller conveyor 24 to transport the pallet P on which the bellows-shaped cardboard sheet stack 60 is placed to the sending-out position 31. During this series of operations, the control unit 21 is in a state in which the measured value of the rotation amount is input from the rotation sensor 44. That is, these operations are performed when the stack detection sensor detects that the bellows-shaped cardboard sheet stack 60 is not present at the sending-out position 31 and the sending-out sensor detects that the long cardboard sheet 61 is being sent to the cardboard blank manufacturing device 50. In addition, since the first sensor 35 detects the presence of the accordion-shaped cardboard sheet stack 60 at a predetermined height position, when the input indicates that the accordion-shaped cardboard sheet stack 60 is “absent”, this includes not only the case where the long cardboard sheet 61 on the pallet P has been completely removed, but also the case where a small amount of the long cardboard sheet 61 remains at a position lower than the detection position of the first sensor 35.

[0058] When the third sensor 37 detects that the pallet P has passed along the second conveying path toward the recovery position 33 where the empty pallet P discharged from the sending position 31 is recovered, the control unit 21 uses the display on the control panel 22 and a warning light to prompt the worker to move the pallet P from the recovery position 33.

[0059] In addition, when the third sensor 37 detects that the pallet P has passed through the second conveying path toward the recovery position 33 where the empty pallet P discharged from the sending position 31 is recovered, the control unit 21 may determine that there is no empty pallet P at the sending position 31, and drive the driving roller 23 of the roller conveyor 24 to transfer the pallet P on which the bellows-shaped cardboard sheet stack 60 is placed to the sending position 31. In this case, the second sensor 36 may be omitted. Furthermore, the control unit 21 may drive the driving roller 23 of the roller conveyor 24 to transfer the pallet P on which the bellows-shaped cardboard sheet stack 60 is placed to the sending position 31 when the detection result of the first sensor is an input indicating that there is no long cardboard sheet 61 on the pallet P, the third sensor has an input indicating that the pallet P has passed through the second conveying path toward the recovery position, and the detection result of the second sensor is an input indicating that there is no pallet P at the sending position 31. That is, the control unit 21 may execute the transfer of the accordion-shaped cardboard sheet stack 60 based on a combination of input states from a plurality of sensors.

[0060] Although the embodiment for carrying out the present invention has been described above, the present invention is not limited to the above embodiment, and appropriate modifications are permitted within the scope of the spirit of the present invention.

[0061] For example, in the above embodiment, the cardboard sheet feeding device 10 and the cardboard blank manufacturing device 50 are each configured to have a control unit and a control panel, but the cardboard sheet feeding device 10 may also be controlled by the control unit 51 of the cardboard blank manufacturing device 50.

[0062] In addition, in the above embodiment, the device has been mainly described as a cardboard sheet feeding device 10, but the device composed of the transfer device 20, various sensors including a stack detection sensor, and a control unit 21 that controls the transfer device 20 based on the sensor input is also a bellows-shaped cardboard sheet stack refilling device.

[0063] In addition, as shown in FIG. 2, in the above embodiment, a pallet conveying mechanism using a pair of roller conveyors 24 is adopted for the transfer device 20 from the viewpoint of being able to withstand the weight of the bellows-shaped cardboard sheet stack 60. However, as long as the conveying mechanism can withstand the weight of the bellows-shaped cardboard sheet stack 60, for example, a belt conveying mechanism in which the bellows-shaped cardboard sheet stack 60 that is not placed on a pallet P is placed on a running endless belt and conveyed may be adopted.

[0064] In the above embodiment, the transfer operation of the bellows-shaped cardboard sheet stack 60 to the sending position 31 has been described in the case where the stack detection sensor detects that the bellows-shaped cardboard sheet stack 60 is not present at the sending position 31 and the sending sensor detects that the long cardboard sheet 61 is sent to the cardboard blank manufacturing device 50, but this is not limiting. In other words, even when the conveyance of the long cardboard sheet 61 is stopped for a short time to cut out the cardboard blank, the control unit 21 may execute the transfer operation of the bellows-shaped cardboard sheet stack 60 to the sending position 31. [Explanation of symbols]

[0065] 10. Cardboard sheet delivery device 20 Transfer device 21 Control section 22 Control Panel 23 Drive roller 24 Roller Conveyor 25 Free Roller 31 Sending position 32 Ready position 33 Recovery location 35 First Sensor 36 Second Sensor 37 3rd Sensor 40 Transmission section 41 Rotating Body 42 Support frame 43 Rotational Axis 44 Rotation Sensor 50 Corrugated cardboard blank manufacturing equipment 51 Control section 52 Control Panel 53 Conveyor 60 Accordion-shaped corrugated cardboard sheet laminate 61 Long cardboard sheets 62 Joint 63 Bellows laminate 64 End of joint 65 End of top layer of bellows laminate 66 Crease for lamination 67 Auxiliary crease L1 Joint length L2 Length between fold lines for lamination L3 Top layer length L4 Height of bellows laminate P Palette

Claims

1. A cardboard sheet delivery device that delivers long cardboard sheets from a bellows-shaped cardboard sheet stack in which long cardboard sheets are folded into a bellows shape at predetermined lengths to a cardboard blank manufacturing device, A delivery section that delivers the long cardboard sheets from the bellows-shaped cardboard sheet stack arranged at a predetermined delivery position to the cardboard blank manufacturing device; A sending sensor that detects whether the sending unit is sending out the long cardboard sheet based on the operating state of the sending unit; a stack detection sensor for detecting whether the accordion-shaped cardboard sheet stack is present at the delivery position; A transfer device for transferring the accordion-shaped corrugated cardboard sheet stack arranged at a predetermined preparation position to the delivery position; A control unit that transfers the bellows-shaped cardboard sheet stack arranged at the preparation position to the delivery position by the transfer device when the stack detection sensor detects that the bellows-shaped cardboard sheet stack is not present at the delivery position; A cardboard sheet feeding device comprising:

2. 2. The cardboard sheet feeding device according to claim 1, wherein the control unit transfers the bellows-shaped cardboard sheet stack arranged at the preparation position to the feeding position by the transfer device when the stack detection sensor detects that the bellows-shaped cardboard sheet stack is not present at the feeding position and when the feeding sensor detects that the feeding unit is feeding the long cardboard sheet.

3. The transfer device includes a pallet transfer mechanism that transfers the bellows-shaped cardboard sheet stack on a pallet, 3. The cardboard sheet delivery device according to claim 1, wherein the stack detection sensor is a first sensor that detects the presence of the accordion-shaped cardboard sheet stack on the pallet at the delivery position.

4. The delivery section includes a rotating body and a support frame that rotatably supports the rotating body at a position higher than the height of the bellows-shaped cardboard sheet stack; The cardboard sheet delivery device according to any one of claims 1 to 3, further comprising:

5. 5. The cardboard sheet delivery device according to claim 4, wherein the delivery sensor is a rotation sensor that detects a rotation state of the rotating body.

6. A cardboard sheet delivery device that delivers long cardboard sheets from a bellows-shaped cardboard sheet stack in which long cardboard sheets are folded into a bellows shape at predetermined lengths to a cardboard blank manufacturing device, A delivery sensor detects whether the long cardboard sheet is being delivered to the cardboard blank manufacturing device from the bellows-shaped cardboard sheet stack arranged at a predetermined delivery position; a stack detection sensor provided at a predetermined height position of the delivery position and detecting whether the remaining amount of the bellows-shaped corrugated cardboard sheet stack is equal to or less than a predetermined amount other than 0; A transfer device for transferring the accordion-shaped corrugated cardboard sheet stack arranged at a predetermined preparation position to the delivery position; a control unit that transfers the bellows-shaped cardboard sheet stack arranged at the preparation position to the delivery position by the transfer device when the stack detection sensor detects that the remaining amount of the bellows-shaped cardboard sheet stack at the delivery position is equal to or less than the predetermined amount; A cardboard sheet feeding device comprising: