System and method for corrugated cardboard

Abstract

The invention discloses a system which comprises a corrugating machine (1). The corrugating machine is provided with a first corrugated board production device (2) for producing a single-sided laminated first corrugated board web (21), a laminating web spreading device (67) for spreading a laminating web (72), and a second corrugated board production device (7) for joining the single-sided laminated first corrugated board web (21) with the laminating web (72) to form a corrugated board with a first outer web (21, 72) and a second outer web (72, 72). 21) and a joining device (88) for a corrugated cardboard web (91) laminated on both sides of the corrugated cardboard web (91). Furthermore, the corrugating machine (1) has at least one cutting device (97) arranged downstream of the joining device (88) for producing the corrugated cardboard sheet (102) from the double-sided laminated corrugated cardboard web (91). Furthermore, the system has a processing device (108) which is designed to automatically match the tension of the second outer web (72, 21), if necessary, with the tension of the first outer web (21, 72), such that the corrugated board sheet (102) is flattened or meets a flatness target value at least in the conveying direction of the corrugated board sheet (102).

Description

[0001] Related Applications

[0002] This patent application claims priority from German patent application DE 10 2022 205 208.0, the contents of which are incorporated by reference into the present patent application. Technical Field

[0003] The present invention relates to a system with a corrugating machine for producing corrugated board. In addition, the present invention also relates to a corrugated board production method. Background Art

[0004] The production of corrugated board is known from previously disclosed applications. In the production of corrugated board, the produced corrugated board always has a curvature, which is not only disadvantageous but also undesirable. Summary of the invention

[0005] The object of the present invention is to provide a system comprising a corrugator which is capable of producing particularly high-quality, in particular (substantially) flat corrugated board in a particularly reliable and efficient manner. Furthermore, the system should be relatively simple. Furthermore, a corresponding method should be provided.

[0006] According to the invention, this object is achieved by the features specified in independent claims 1 and 15. The core of the invention is that the (mechanical) tension / web tension of the second outer web is matched to the mechanical tension / web tension of the first outer web, if necessary, by means of a processing device. At least the tension of the second outer web is adjustable. Preferably, an absolute control of the web tension level is not required.

[0007] In particular, the object of the invention is to adapt the tensions of the first outer web and the second outer web to one another, thereby achieving a stable flatness of the corrugated board without upward or downward bending, at least in the running direction.

[0008] The tension level is dependent on material dependencies / properties and / or possibly required additional interventions, which are preferably (necessarily) carried out by the operator. The aim is to achieve the lowest possible tension level, which advantageously lies within certain or prescribed limits for the minimum and / or maximum tension. The tension level is preferably adapted to the paper substrate (type, basis weight or other) of the web.

[0009] Preferably, the operator can select which web is the first outer web. For double-sided laminated corrugated board (webs) or finished corrugated board, the outer web is or includes the web that is located on the outside and is therefore visible from the outside. For example, the first outer web forms the outer cover layer or the inner cover layer, while the second outer web forms the corresponding other cover layer. The web that does not form the first outer web thus forms the second outer web. During the corrugated board production process or for the finished corrugated board, the outer cover layer is preferably arranged facing upward or above the corresponding inner cover layer.

[0010] Advantageously, the finished corrugated board is flat or meets a target value for flatness both in the conveying direction and perpendicularly thereto in the transverse direction.

[0011] Preferably, the processing device is in particular an electric or electronic information or data processing device. It is preferably designed as a control device and is, for example, a component of a corrugated machine. Alternatively, the processing device is, for example, located at a higher level of the corrugated machine and is at least temporarily in signal connection with it.

[0012] The first corrugated board production device preferably comprises a first corrugating device for producing a first corrugated web from a first material web and a first gluing device for applying glue on the first corrugated web. Advantageously, the first corrugated board production device additionally comprises a first pressing device for pressing another material web and the first corrugated web applied with glue together to form a single-sided laminated first corrugated web.

[0013] Advantageously, first and second unrolling devices for unrolling the first and second material webs are arranged upstream of the first corrugated board production device. The unrolling devices are preferably designed as splicing devices for unrolling material webs of unlimited length.

[0014] Advantageously, the laminated web unwinding device is designed as a laminated web splicing device for unwinding a laminated web of unlimited length.

[0015] The joining device is preferably designed as a heating and pulling device. It is preferably capable of pressing the first single-sided laminated corrugated board web and the laminated web together, and directly or indirectly joining them to each other in a glue-coated manner.

[0016] At least one cutting device is preferably designed as a cross-cutting device. Advantageously, the device comprises at least one cutting medium, such as a cutting knife, a cutting edge or others.

[0017] Further advantageous embodiments of the invention are disclosed in the dependent claims.

[0018] The presetting device according to the dependent claim 2 realizes a particularly user-friendly system. Advantageously, the system or the corrugator is operated via the presetting device. Advantageously, the presetting device has an input device for inputting a target tension for the first outer web. For example, the input device contains, in particular, a slide, a wheel or something else in order to correct the curvature of the corrugated board or to adjust the tension difference between the outer webs. The input of the tension must or can only be carried out for the first outer web.

[0019] Advantageously, the presetting device is arranged on the upper level of the corrugating machine. As an alternative, the device is a component of the corrugating machine.

[0020] Advantageously, the presetting is performed by the presetting device at the start of a quality. Advantageously, if the tension difference between the first outer web and the second outer web is not equal to zero when the last storage, in particular when the quality is stored, the corresponding tension difference is taken into account. Preferably, at least one minimum and / or maximum tension value is stored as a default value to be set and can preferably be changed for all qualities if necessary.

[0021] Advantageously, the preset data can be adjusted by manual intervention in the laminating area. If adjustments are to be generally applied, the operator can request the data in the preset device. In the case of a one-time result, the changes are advantageously not taken into account.

[0022] The system according to dependent claim 3 is particularly simple. It is only necessary to input a target tension for the first outer web. The processing device automatically or autonomously adjusts the tension of the second outer web. The device has the relevant capability.

[0023] According to dependent claim 4, a master / slave relationship exists in order to adapt the tension of the second outer web to the tension of the first outer web.

[0024] Preferably, the tension comparison unit according to dependent claim 5 determines a tension difference between the tension of the first outer web and the tension of the second outer web. This enables a particularly good tension setting or regulation.

[0025] The system according to dependent claim 6 is particularly reliable.

[0026] Flat corrugated board can be achieved relatively easily with the system according to dependent claim 7. In particular, the aim is always to achieve mutually balanced web tensions, so that good flatness of the corrugated board can be ensured right from the start.

[0027] According to dependent claim 8, the system has a tension difference control device, which is particularly efficient and leads to high-quality corrugated board.

[0028] According to the dependent claim 9, the first outer web is formed by a laminated web or is a component of a first corrugated board web laminated on one side. The second outer web is formed by another web or is a component thereof.

[0029] The at least one laminating web tension changing device according to dependent claim 10 is designed, for example, as a brake and / or drive device. The device is, for example, a component of a laminating web unwinding device and can influence the unwinding of the laminating web accordingly. By increasing the unwinding braking force during the unwinding of the laminating web, the tension of the laminating web is increased. By reducing the unwinding braking force during the unwinding of the laminating web, the tension of the laminating web is reduced.

[0030] Alternatively, for example, at least one laminate web tension changing device is separately designed, in particular a laminate web unfolding device, and can act accordingly on the laminate web. The device is designed, for example, as a laminate web tension changing roller. In order to brake the laminate web, that is, to increase the tension of the laminate web, the circumferential speed of the corresponding laminate web tension changing roller is reduced to be less than the prevailing conveying speed of the laminate web at this location. Alternatively or additionally, the laminate web contact angle around the corresponding laminate web tension changing roller can be increased. In order to drive the laminate web, that is, to reduce the tension of the laminate web, the circumferential speed of the corresponding laminate web tension changing roller is increased to be greater than the prevailing conveying speed of the laminate web at this location. Alternatively or additionally, the laminate web contact angle around the laminate web tension changing roller can be reduced.

[0031] Preferably, at least one first corrugated cardboard web tension changing device according to dependent claim 11 is designed as a braking and / or driving device and can act accordingly on the single-sided laminated first corrugated cardboard web. Advantageously, the device is designed as at least one first corrugated cardboard web tension changing roller. Advantageously, at least one first corrugated cardboard web tension changing device is arranged on the bridge of the corrugator. In order to brake the single-sided laminated first corrugated cardboard web, that is, to increase the tension of the single-sided laminated first corrugated cardboard web, the circumferential speed of the corresponding first corrugated cardboard web tension changing roller is reduced to be less than the prevailing conveying speed of the single-sided laminated first corrugated cardboard web at this location. As an alternative or in addition, the contact angle of the single-sided laminated first corrugated cardboard web around the corresponding first corrugated cardboard web tension changing roller can be increased. In order to drive the single-sided laminated first corrugated cardboard web, i.e. to reduce the tension of the single-sided laminated first corrugated cardboard web, the peripheral speed of the tension changing roller corresponding to the first corrugated cardboard web is increased to be greater than the prevailing conveying speed of the single-sided laminated first corrugated cardboard web at this location. Alternatively or additionally, the contact angle of the single-sided laminated first corrugated cardboard web around the tension changing roller corresponding to the first corrugated cardboard web can be reduced.

[0032] The at least one laminate web tension measuring device according to the dependent claim 12 is designed, for example, as a laminate web tension measuring or sensor roller. Advantageously, the at least one laminate web tension measuring device is directly in contact with the laminate web. Preferably, the device is capable of measuring the tension of the laminate web or providing measurement values ​​related to the tension of the laminate web. For example, the measurement is performed continuously or at periodic time intervals. Advantageously, the at least one laminate web tension measuring device has at least one integrated or attached dynamometer, force block, force measuring bearing and / or tension sensor. The device outputs a corresponding measurement signal. Alternatively, laminate web tension measuring devices of other designs can be used.

[0033] Advantageously, at least one first corrugated cardboard web tension measuring device according to dependent claim 13 is designed as a first corrugated cardboard web tension measuring or sensor roller. Advantageously, at least one first corrugated cardboard web tension measuring device is directly attached to the first single-sided laminated corrugated cardboard web. Preferably, the device is capable of measuring the tension of the first single-sided laminated corrugated cardboard web, or providing measurement values ​​related to the tension of the first single-sided laminated corrugated cardboard web. For example, the measurement is performed continuously or at periodic time intervals. For example, advantageously, at least one first corrugated cardboard web tension measuring device has at least one integrated or installed dynamometer, force block, force bearing and / or tension sensor. The device outputs a corresponding measurement signal. Alternatively, first corrugated cardboard web tension measuring devices of other designs can be used.

[0034] Preferably, the at least one curvature determination device according to dependent claim 14 operates in a contactless manner. Advantageously, the device is designed as a sensor, camera or the like and is capable of providing a corresponding measurement signal. Such a system is particularly operator-friendly and has a particularly low demand for manpower. Alternatively or additionally, a manual or manual determination of the curvature of the corrugated board is performed.

[0035] The developments according to dependent claims 2 to 14 also relate to preferred developments of the method according to dependent claim 15 .

[0036] The corrugator has, for example, a plurality of corrugated board production devices to produce a plurality of corresponding single-sided laminated corrugated board webs. Advantageously, the double-sided laminated corrugated board webs are three-layer, five-layer or seven-layer.

[0037] Advantageously, the corrugator comprises at least a second or another corrugated board production device for producing at least one second / another corrugated board web laminated on one side, and preferably comprises at least one second / another corrugated board tension changing device matched with at least one second single-sided laminated corrugated board web and at least temporarily in signal connection with the processing device, so as to change the tension of at least one second single-sided laminated corrugated board web when necessary. Such a system can efficiently realize the production of high-quality corrugated board with multiple layers and flatness. Advantageously, at least one second corrugated board production device adopts the same design as the second corrugated board production device. Advantageously, at least one second corrugated board web tension changing device adopts the same design as at least one first corrugated board web tension changing device. As an alternative, there is a difference between the two. Advantageously, there is also at least one second / another corrugated board web tension measuring device for measuring the tension of at least one second single-sided laminated corrugated board web, which preferably adopts the same design as the first corrugated board web tension measuring device. As an alternative, there is a difference between the two. Preferably, if present, at least one second single-sided laminated corrugated board web is located on the inner side of the double-sided laminated corrugated board (web) or the finished corrugated board. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] The preferred embodiments of the present invention are described below with reference to the accompanying drawings. In the accompanying drawings:

[0039] Figure 1 A first part of a corrugator as part of the system according to the invention is shown;

[0040] Figure 2 showing a second portion of the corrugator machine engaged with the first portion;

[0041] Figure 3 The scale is shown on an enlarged scale. Figure 1 Detail section marked III, which shows a preheating device arranged upstream of the joining device and its surroundings;

[0042] Figure 4 Shown on an enlarged scale Figure 1 Detail section IV, which exemplarily shows the discharge port of the high-speed conveying device and its surroundings;

[0043] Figure 5 Shown on an enlarged scale Figure 2 a detail portion V marked in the figure, which mainly shows the processing device;

[0044] Figure 6 shows a perspective view of a tension measuring device as part of the illustrated corrugator;

[0045] Figure 7 shows a perspective view of an alternative tension measuring device as part of the illustrated corrugator and supported in a support;

[0046] Figure 8 A perspective view showing a stacking device and a curvature measuring device of the corrugator shown;

[0047] Fig. 9 The control system of the system is shown in a simplified manner;

[0048] Fig.10 The tension difference control system of the system shown is shown in a block diagram, and

[0049] Fig.11 Another block diagram shows the tension difference control process of the system shown DETAILED DESCRIPTION

[0050] exist Figure 1 , Figure 2 The corrugator 1 shown as a whole in FIG. 1 comprises a first corrugated board production device 2 for producing a first single-sided laminated corrugated board web of unlimited length.

[0051] A first cover web splicing device 3 and a first material web splicing device 4 are arranged upstream of the first corrugated board production device 2 .

[0052] The first cover web splicing device 3 comprises a first unrolling unit 6 for unrolling a first cover web of limited length from a first cover web roll 5 and a second unrolling unit 8 for unrolling a second cover web of limited length from a second cover web roll 7. The first cover web of limited length and the second cover web are joined to each other so as to provide a first cover web 9 of unlimited length by means of a joining and cutting unit (not shown) of the first cover web splicing device 3.

[0053] The first material web splicing device 4 is formed corresponding to the first cover web splicing device 3. It comprises a third unrolling unit 11 for unrolling a first material web of limited length from a first material web roll 10 and a fourth unrolling unit 13 for unrolling a second material web of limited length from a second material web roll 12. The first material web of limited length and the second material web are joined to each other to provide a first material web 14 of unlimited length by means of a joining and cutting unit (not shown) of the first material web splicing device 4.

[0054] The first cover web 9 of unlimited length is fed through the first heating roller 15 of the first heating device 16 and the first tension control device 17 of the first corrugated board production device 2. The first heating device 16 is capable of heating the first cover web 9 of unlimited length. The first tension control device 17 is capable of changing or regulating the tension of the first cover web 9 of unlimited length. The first material web 14 of unlimited length is fed through the reversing roller of the first corrugated board production device 2.

[0055] In order to produce an infinite length first corrugated web with a corrugated structure from an infinite length first material web 14, the first corrugated board production device 2 comprises a first corrugating roller device 18 with a first corrugating roller 19 and a second corrugating roller 20. In order to allow the infinite length first material web 14 to pass through and produce the corrugated structure, the corrugating rollers 19, 20 form a first corrugating roller gap. The rotation axes of the corrugating rollers 19, 20 are parallel to each other and perpendicular to the infinite length first material web 14.

[0056] In order to join the first cover layer web 9 of infinite length with the first material web of infinite length or the corrugated web 14 after the corrugation production to form a first corrugated board web 21 of infinite length laminated on one side, the first corrugated board production device 2 has a first gluing device 22, which preferably includes a first glue metering roller, a first glue container and a first gluing roller. In order to allow the first corrugated board web 14 of infinite length to pass through and be glued, the first gluing roller and the first corrugated roller 19 form a first gluing gap. The glue in the first glue container is applied to the top of the corrugated structure of the first corrugated board web 14 of infinite length by the first gluing roller. The first glue metering roller is close to the first gluing roller and is used to form a uniform glue layer on the first gluing roller.

[0057] Next, in the first corrugated board production device 2, the first cover layer web 9 of infinite length is joined to the first corrugated board web 14 of infinite length smeared with glue from the first glue container. In order to press the first cover layer web 9 of infinite length onto the first corrugated board web 14 of infinite length smeared with glue and partially abutting the first corrugated roller 19, the first corrugated board production device 2 has a first pressing module 23, which is advantageously designed as a pressing belt module. The module is arranged above the first corrugated roller 19 and has two first reversing rollers and a first pressing belt of infinite length, which is guided around the two first reversing rollers. The first corrugated roller 19 partially extends from the bottom in the area between the two first reversing rollers of the first pressing module 23, so that the first pressing belt is deflected by the first corrugated roller 19. The first pressing belt is pressed onto the first cover layer web 9 of infinite length, which in turn is pressed onto the first corrugated board web 14 of infinite length smeared with glue and abutting the first corrugated roller 19.

[0058] For temporary storage and buffering of the first single-sided laminated corrugated board web 21 of unlimited length, it is conveyed by a first high-speed conveyor 24 to a first storage device 25 of the corrugator 1 and looped or can be looped there.

[0059] The first storage device 25 has a first conveying device for conveying the first corrugated cardboard web 21 with an infinite length laminated on one side. The first conveying device forms a conveying section for the first corrugated cardboard web 21 with an infinite length laminated on one side. In the first conveying device, a first roller 106 is supported in a rotatable manner or a rotatably driven manner. When conveying the first corrugated cardboard web 21 with an infinite length laminated on one side through the first conveying device, it is conveyed along the first conveying roller 106, and the roller is rotated in the process.

[0060] Furthermore, the corrugator 1 has a second corrugated board production device 26 which is designed according to the first corrugated board production device 2 and is used for producing a second single-sided laminated corrugated board web of unlimited length.

[0061] A second cover web splicing device 27 and a second material web splicing device 28 are arranged upstream of the second corrugated board production device 26 .

[0062] The second cover web splicing device 27 comprises a fifth unrolling unit 30 for unrolling a third cover web of limited length from a third cover web roll 29 and a sixth unrolling unit 32 for unrolling a fourth cover web of limited length from a fourth cover web roll 31. The third cover web and the fourth cover web of limited length are joined to each other so as to provide a second cover web 33 of unlimited length by means of a joining and cutting unit not shown in the second cover web splicing device 27.

[0063] The second material web splicing device 28 comprises a seventh unrolling unit 35 for unrolling a third material web of limited length from a third material web roll 34 and an eighth unrolling unit 37 for unrolling a fourth material web of limited length from a fourth material web roll 36. The third material web and the fourth material web of limited length are joined to each other to provide a second material web 38 of unlimited length by means of a joining and cutting unit (not shown) of the second material web splicing device 28.

[0064] The second cover web 33 of unlimited length is fed through the second heating roller 39 of the second heating device 40 and the second tension control device 41 of the second corrugated board production device 26. The second heating device 40 is capable of heating the second cover web 33 of unlimited length. The second tension control device 41 is capable of changing or regulating the tension of the second cover web 33 of unlimited length. The second material web 38 of unlimited length is fed through the reversing roller of the second corrugated board production device 26.

[0065] In order to produce the second corrugated web of infinite length with a corrugated structure from the second material web 38 of infinite length, the second corrugated board production device 26 comprises a second corrugating roller device 42 with a third corrugating roller 43 and a fourth corrugating roller 44. In order to allow the second material web 38 of infinite length to pass through and produce the corrugated structure, the corrugating rollers 43 and 44 form a second corrugating roller gap. The rotation axes of the corrugating rollers 43 and 44 are parallel to each other and perpendicular to the second material web 38 of infinite length.

[0066] In order to join the second cover layer web 33 of infinite length with the second material web of infinite length or the corrugated web 38 after the corrugation production to form a second corrugated board web 45 of infinite length laminated on one side, the second corrugated board production device 26 has a second gluing device 46, which preferably includes a second glue metering roller, a second glue container and a second gluing roller. In order to allow the second corrugated board web 38 of infinite length to pass through and be glued, the second glue roller and the second corrugated roller 43 form a second gluing gap. The glue in the second glue container is applied to the top of the corrugated structure of the second corrugated board web 38 of infinite length by the second glue roller. The second glue metering roller is close to the second glue roller and is used to form a uniform glue layer on the second glue roller.

[0067] Next, in the second corrugated board production device 26, the second cover layer web 33 of infinite length is joined to the second corrugated board web 38 of infinite length smeared with glue from the second glue container. In order to press the second cover layer web 33 of infinite length onto the second corrugated board web 38 of infinite length smeared with glue and partially abutting against the third corrugated roller 43 again, the second corrugated board production device 26 has a second pressing module 47. The second pressing module 47 is advantageously designed as a pressing belt module. It is arranged above the third corrugated roller 43. The second pressing module 47 has two second reversing rollers and a second pressing belt of infinite length, which is guided around the two second reversing rollers. The third corrugated roller 43 partially extends from the bottom in the area between the two second reversing rollers of the second pressing module 47, so that the second pressing belt is reversed by the third corrugated roller 43. The second pressing belt presses on the second cover web 33 of infinite length, which in turn presses on the second corrugated web 38 of infinite length which is coated with glue and rests on the third corrugating roller 43 .

[0068] For temporary storage and buffering of the single-sided laminated second corrugated board web 45 of unlimited length, it is conveyed by a second high-speed conveyor 48 to a second storage device 49 of the corrugator 1 and looped or can be looped there.

[0069] The second storage device 49 has a second conveying device for conveying the second corrugated cardboard web 45 laminated on one side with an infinite length. The second conveying device forms a conveying section for the second corrugated cardboard web 45 laminated on one side with an infinite length. In the second conveying device, a second roller 107 is supported in a rotatable manner or a rotatably driven manner. When conveying the second corrugated cardboard web 45 laminated on one side with an infinite length through the second conveying device, it is conveyed along the second conveying roller 107, and the roller is rotated in the process.

[0070] The first single-sided laminated corrugated cardboard web 21 of unlimited length is transported to the bridge 50 of the corrugator 1 by the first high-speed conveyor 24 for further transport. The second single-sided laminated corrugated cardboard web 45 of unlimited length is also transported to the bridge 50 by the second high-speed conveyor 48 for further transport.

[0071] The bridge 50 supports a first de-looping device 51 with a first de-looping roller 52 in the downstream terminal area, which ensures the de-looping of the first single-sided laminated corrugated cardboard web of infinite length 21. The first de-looping rollers 52 are arranged horizontally at a certain distance from each other at the same height in principle and extend perpendicularly to the conveying direction of the first single-sided laminated corrugated cardboard web of infinite length 21. The first single-sided laminated corrugated cardboard web of infinite length 21 passes through the first de-looping device 51.

[0072] In addition, the bridge 50 supports a second unlooping device 53 in the downstream terminal region, which is designed identically to the first unlooping device 51 and ensures the unlooping of the second single-sided laminated corrugated cardboard web of infinite length 45 there. The second unlooping device 53 is arranged below the first unlooping device 51 and comprises two unlooping rollers 54. The second unlooping rollers 54 are arranged horizontally at a distance from each other at the same height in principle and extend perpendicularly to the conveying direction of the second single-sided laminated corrugated cardboard web of infinite length 45. The second single-sided laminated corrugated cardboard web of infinite length 45 passes through the second unlooping device 53.

[0073] A first guide device 55 for guiding the first single-sided laminated infinite length corrugated cardboard web 21 is arranged on the bridge 50 downstream of the first unlooping device 51. The first guide device 55 detects the transverse position of the first single-sided laminated infinite length corrugated cardboard web 21. If necessary, it corrects the transverse position of the first single-sided laminated infinite length corrugated cardboard web 21 and, if necessary, ensures in particular the transverse alignment of the first single-sided laminated infinite length corrugated cardboard web 21 relative to the center of the device or to the second single-sided laminated infinite length corrugated cardboard web 42 or to the laminated web.

[0074] A first splicing collecting device 57 is arranged in the first guide device 55 or at a position adjacent thereto, which can collect the width change of the first single-sided laminated corrugated cardboard web 21 of infinite length and / or directly collect the splicing position in the first single-sided laminated corrugated cardboard web 21 of infinite length. For this purpose, the first splicing collecting device 57 has a first web collecting roller 58 that is rotatable and abuts against the first single-sided laminated corrugated cardboard web 21 of infinite length, and a non-contact first scanning device for scanning the side area of ​​the first single-sided laminated corrugated cardboard web 21 of infinite length.

[0075] Furthermore, a second guide device 56 for guiding the second single-sided laminated infinite length corrugated cardboard web 45 is arranged on the bridge 50 downstream of the second unlooping device 53. The second guide device 56 detects the transverse position of the second single-sided laminated infinite length corrugated cardboard web 45. If necessary, it corrects the transverse position of the second single-sided laminated infinite length corrugated cardboard web 45 and, if necessary, ensures in particular the transverse alignment of the second single-sided laminated infinite length corrugated cardboard web 45 relative to the center of the device or to the first single-sided laminated infinite length corrugated cardboard web 21 or to the laminated web.

[0076] A second splicing collection device 59 is arranged in the second guide device 56 or at a position adjacent thereto. The design of the second splicing collection device 59 is the same as that of the first splicing collection device 57 and can collect the width change of the second single-sided laminated infinite length corrugated cardboard web 45 and / or directly collect the splicing position in the second single-sided laminated infinite length corrugated cardboard web 45. For this purpose, the second splicing collection device 59 has a second web collection roller 60 that is rotatable and abuts against the second single-sided laminated infinite length corrugated cardboard web 45 and a non-contact second scanning device for scanning the side area of ​​the second single-sided laminated infinite length corrugated cardboard web 45. The splicing position can be synchronized.

[0077] A first tension changing device 61 is arranged on the bridge 50 downstream of the first guide device 55, which is preferably rubber-coated and can be driven and / or braked by a first drive device 62, in particular a servo drive device. The first drive device 62 has a first torque measuring unit or the first torque measuring unit is associated with the first drive device 62. The first tension changing roller 61 ensures in particular a taut or tensioned single-sided laminated infinite length first corrugated board web 21, the tension of which is preferably kept constant. The single-sided laminated infinite length first corrugated board web 21 is guided around the first tension changing roller 61.

[0078] A reversing roller 63 is arranged upstream from the first tension changing roller 61 .

[0079] A second tension changing device 64 is arranged on the bridge 50 downstream of the second guide device 56, which is preferably coated with rubber and can be driven and / or braked by a second drive device 65, in particular a servo drive device. The second drive device 65 has a second torque measuring unit or the second torque measuring unit is associated with the second drive device 65. The second tension changing roller 64 ensures in particular a taut or tensioned single-sided laminated infinite length second corrugated board web 45, the tension of which is preferably kept constant. The single-sided laminated infinite length second corrugated board web 45 is guided around the second tension changing roller 64.

[0080] A reversing roller 66 is arranged upstream from the second tension changing roller 64 .

[0081] In addition, the corrugator 1 has a laminated web splicing device 67, which includes a ninth unwinding unit 69 for unwinding a first laminated web of limited length from a first laminated web roll 68 and a tenth unwinding unit 71 for unwinding a second laminated web of limited length from a second laminated web roll 70. The first laminated web of limited length and the second laminated web of limited length are joined to each other so as to provide a laminated web 72 of unlimited length by means of a joining and cutting unit (not shown) of the laminated web splicing device 67.

[0082] The ninth unfolding unit 69 and the tenth unfolding unit 71 respectively have an unfolding brake 69a or 71a in order to apply an unfolding braking force on the first or second laminating web of limited length or the first or second laminating web roller 68, 70 when necessary, which preferably (also) depends on the current diameter of the first laminating web roller 68 or the second laminating web roller 70.

[0083] Downstream of the tension change rollers 61, 64 and the laminated web splicing device 67, the corrugator 1 has a preheating device 73, which includes three preheating rollers 74, 75, 76 arranged one above the other. The single-sided laminated infinite length corrugated board webs 21, 45 and the infinite length laminated web 72 are fed to the preheating device 73. The single-sided laminated infinite length first corrugated board web 21 is wound around the first preheating roller 74 and heated. The single-sided laminated infinite length second corrugated board web 45 is wound around the second preheating roller 75 and heated. The infinite length laminated web 72 is wound around the third preheating roller 76 and heated.

[0084] A first tension measuring roller 77 is arranged downstream and adjacent to the first preheating roller 74, which is in direct mechanical contact with the first single-sided laminated infinite length corrugated cardboard web 21 and can measure its mechanical (web) tension there. The first tension measuring roller 77 extends perpendicularly to the first single-sided laminated infinite length corrugated cardboard web 21. It has a horizontal orientation.

[0085] A second tension measuring roller 78 is arranged downstream and adjacent to the second preheating roller 75, which is in direct mechanical contact with the second single-sided laminated infinite length corrugated cardboard web 45 and can measure its mechanical (web) tension there. The second tension measuring roller 78 extends perpendicularly to the second single-sided laminated infinite length corrugated cardboard web 45. It has a horizontal profile.

[0086] A third tension measuring roller 79 is arranged downstream and adjacent to the third preheating roller 76. The infinite length of the laminated web 72 is guided around the third tension measuring roller 79. The third tension measuring roller 79 is in direct mechanical contact with the infinite length of the laminated web 72 and can measure its mechanical (web) tension there. The third tension measuring roller 79 extends perpendicularly to the infinite length of the laminated web 72. It has a horizontal profile.

[0087] like Figure 6 As shown, each tension measuring roller 77, 78, 79 has a force measuring bearing 80 on both sides, which can detect the bearing forces generated and thus determine the mechanical tension of the corresponding web 21, 45 or 72. Advantageously, each force measuring bearing 80 has a radial force sensor.

[0088] like Figure 7 As shown, the first tension measuring roller 77, the second tension measuring roller 78 and / or the third tension measuring roller 79 can be associated with a guide roller 81 for guiding the corresponding web 21, 45 or 72. The tension measuring rollers 77, 78 or 79 and the guide roller 81 are fixed by a support 82 and are parallel to each other.

[0089] Downstream of the tension measuring rollers 77, 78, 79, the corrugator 1 has a glue mechanism 83 with a first glue roller 84 and a second glue roller 85, each of which is partially immersed in the corresponding glue tank. A glue metering roller 86 is attached to each glue roller 84, 85 so that a uniform glue layer is formed on the corresponding glue roller 84 or 85. The corrugated web 14 of the first corrugated board web 21 of infinite length laminated on one side comes into contact with the first glue roller 84, so that its corrugated structure is coated with glue from the corresponding glue tank. The corrugated web 38 of the second corrugated board web 45 of infinite length laminated on one side comes into contact with the second glue roller 85, so that its corrugated structure is coated with glue from the corresponding glue tank. The laminated web 72 of infinite length is not coated with glue in the glue mechanism 83.

[0090] In addition, the glue device 83 comprises a fourth tension measuring roller 87, which is designed, for example, identically to the tension measuring rollers 77, 78 or 79. The infinite length of the laminated web 72 is guided around the fourth tension measuring roller 87 and is in direct mechanical contact with it, so that the fourth tension measuring roller 87 can measure its mechanical (web) tension there. The fourth tension measuring roller 79 extends perpendicularly to the infinite length of the laminated web 72. It has a horizontal profile.

[0091] Downstream of the glue mechanism 83, the corrugator 1 comprises a joining device 88 with a horizontal heating table 89. At a position adjacent to the heating table 89, the joining device 88 has an infinite length pressing belt 90 guided around a guide roller. A pressing gap is formed between the pressing belt 90 and the heating table 89, through which the single-sided laminated infinite length glued corrugated cardboard webs 21, 45 and the infinite length laminated web 72 are guided to form a double-sided laminated infinite length corrugated cardboard web 91. The double-sided laminated infinite length corrugated cardboard web 91 has a total of five layers. The single-sided laminated infinite length first corrugated cardboard web 21 forms the top first outer web of the double-sided laminated infinite length corrugated cardboard web 91. The infinite length laminated web 72 forms the bottom second outer web of the double-sided laminated infinite length corrugated cardboard web 91. The single-sided laminated infinite length second corrugated cardboard web 45 is arranged in the middle or on the inside.

[0092] Downstream of the splicing device 88, the corrugator 1 comprises a short cross-cutting device 92, which comprises at least one cross-cutting roller. The short cross-cutting device 92 is capable, for example, of cutting off waste from the double-sided laminated infinite length corrugated board web 91 and / or of forming splicing cuts between correspondingly changing longitudinal cuts in the double-sided laminated infinite length corrugated board web 91 when a web switch is performed.

[0093] Downstream of the short cross-cut device 92, the corrugator 1 has a slitting / grooving device 93 for slitting and grooving the double-sided laminated infinite length corrugated board web 91. The slitting / grooving device 93 has two groove stations arranged one behind the other and two slitting stations arranged one behind the other. In the slitting / grooving device 93, the double-sided laminated infinite length corrugated board web 91 can be formed into infinite length sub-webs 94, 95 by at least one slitting in the slitting / grooving device 93, which initially run side by side.

[0094] Downstream of the slitting / grooving device 93, the corrugator 1 comprises a branch 96 in order to convey the sub-webs 94, 95 of unlimited length to different levels.

[0095] Downstream of the branch 96, the corrugator 1 comprises a cross-cutting device 97 with two cross-cutting devices 98, 99 arranged one above the other. Each cross-cutting device 98, 99 has two knife-carrying rollers arranged in pairs and with radially protruding knife-carrying rollers. For cross-cutting the sub-webs 94, 95 of unlimited length, the knife-carrying rollers of the corresponding cross-cutting device 98 or 99 interact with each other.

[0096] A conveyor belt device 100 or 101 is arranged downstream of each cross-cutting device 98 , 99 in order to further convey the corrugated board sheet 102 formed from the sub-webs 94 , 95 of unlimited length through the cross-cutting devices 98 , 99 .

[0097] Downstream of each conveyor belt device 100 , 101 is arranged a storage device 103 , which is advantageously height-adjustable. In the storage device 103 , the corrugated cardboard sheets 102 can be stacked one above the other to form a stack 104 .

[0098] In addition, the system comprises a curvature determination device 105, which is arranged above the stack 104 in the storage device 103 and is capable of determining or measuring the corresponding prevailing curvature of the corrugated board sheet 102 in the longitudinal direction. The curvature determination device 105 can be a component of the corrugator 1. For example, the corrugated board may be warped upward or downward. S-shaped warping may also occur.

[0099] Furthermore, the system comprises a processing device 108 which is designed as an electric or electronic control device and which is used in particular for controlling the web tension.

[0100] The first roller 106 is at least temporarily in signal connection with the processing device 108 via the first signal line 109. In this way, a signal or information about the peripheral speed of the first roller 106 is provided to the processing device 108. The first roller 106 can calculate the length of the currently stored single-sided laminated infinite length first corrugated board web 21.

[0101] The second roller 107 is at least temporarily in signal connection with the processing device 108 via the second signal line 110. In this way, a signal or information about the peripheral speed of the second roller 107 is provided to the processing device 108. The second roller 107 can calculate the length of the currently stored single-sided laminated infinite length second corrugated board web 45.

[0102] The first deployment brake 69 a is at least temporarily in signal connection with the processing device 108 via the third signal line 111 and is able to receive an actuation signal from the processing device 108 .

[0103] The second deployment brake 71 a is at least temporarily in signal connection with the processing device 108 via the fourth signal line 112 and is capable of receiving an actuation signal from the processing device 108 .

[0104] The first web collecting roller 58 is at least temporarily in signal connection with the processing device 108 via a fifth signal line 113 in order to provide the processing device 108 with a signal which specifically relates to the moment of collecting the splicing location in the first single-sided laminated corrugated board web 21 of infinite length.

[0105] The second web acquisition device 60 is at least temporarily in signal connection with the processing device 108 via the sixth signal line 114 so as to provide the processing device 108 with a signal specifically relating to the moment of acquisition of the splicing location in the second corrugated board web 45 of infinite length laminated on one side.

[0106] The first tension measuring roller 77 is at least temporarily in signal connection with the processing device 108 via the seventh signal line 115 so as to provide the processing device 108 with a signal which specifically relates to the current mechanical tension of the first corrugated board web 21 of infinite length laminated on one side at the first tension measuring roller 77 .

[0107] The second tension measuring roller 78 is at least temporarily in signal connection with the processing device 108 via the eighth signal line 116 so as to provide the processing device 108 with a signal which specifically relates to the current mechanical tension of the second corrugated cardboard web 45 of infinite length laminated on one side at the second tension measuring roller 78 .

[0108] The third tension measuring roller 79 is at least temporarily in signal connection with the processing device 108 via a ninth signal line 117 in order to provide the processing device 108 with a signal which specifically relates to the current mechanical tension of the infinite length of the laminated web 72 at the third tension measuring roller 79 .

[0109] The fourth tension measuring roller 87 is at least temporarily in signal connection with the processing device 108 via a tenth signal line 118 in order to provide the processing device 108 with a signal which specifically relates to the current mechanical tension of the infinite length of the laminated web 72 at the fourth tension measuring roller 87 .

[0110] Each curvature determination device 105 is at least temporarily in signal connection with the processing device 108 via an eleventh signal line 119 in order to provide the processing device 108 with a signal specifically relating to the last acquired curvature of the corrugated board sheet 102 in the longitudinal direction.

[0111] The first driving device 62 is at least temporarily in a signal connection state with the processing device 108 via the twelfth signal line 129 , and is capable of receiving an actuation signal from the processing device 108 .

[0112] The second driving device 65 is at least temporarily in signal connection with the processing device 108 via the thirteenth signal line 130 , and is capable of receiving an actuation signal from the processing device 108 .

[0113] In addition to the corrugating machine 1 , the system also comprises a higher-level electric or electronic presetting device 120 , which is at least temporarily in signal connection with the processing device 108 in order to preset the tension.

[0114] In the following, the operation of the system or the control of the corrugator 1 will first be briefly explained. Fig. 9 As described above, the processing device 108 is supplied with electrical signals or information from the corrugator 1, the curvature determination device 105, the presetting device 120 and, if necessary, also from the quality data memory 121. The processing device 108 processes this information.

[0115] Fig.10 The control system is shown in more detail in FIG. The control of the tension difference is performed by means of the processing device 108. The tension difference is preferably preset by means of a slider of a preset device 120 of the corrugator 1.

[0116] The processing device 108 receives corresponding signals or information from the preset device 120 and can operate the laminated web splicing device 67, especially its unfolding brake 69a or 71a, the first drive device 62 and / or the second drive device 65 accordingly when necessary. The laminated web splicing device 67, especially its unfolding brake 69a or 71a, the first drive device 62 and / or the second drive device 65 form an actuator. In this way, the mechanical tension of the first single-sided laminated infinite length corrugated board web 21, the second single-sided laminated infinite length corrugated board web 45 or the laminated web 72 of infinite length will be changed or targeted as needed or within a required range.

[0117] The controlled system comprises a first single-sided laminated corrugated cardboard web 21 of infinite length, a second single-sided laminated corrugated cardboard web 45 of infinite length and / or a laminated web 72 of infinite length, up to the tension measuring rollers 77, 78, 79 or 87. This controlled system is Fig.10 122. The control variable is specifically the mechanical tension of the first single-sided laminated infinite length corrugated board web 21, the second single-sided laminated infinite length corrugated board web 45 or the laminated web 72 of infinite length, which is controlled or influenced in a targeted manner.

[0118] A signal may be provided to the controlled system 122, which Fig.10 123. These signals may relate to the quality of the corrugated board sheet 102, at least local speed changes of the corrugator 1 and / or operating signals of the laminating web splicing device 67.

[0119] Preferably, the output variable of the control circuit 122 is provided to the third tension measuring roller 79 , the fourth tension measuring roller 87 , the first tension measuring roller 77 and / or the second tension measuring roller 78 .

[0120] The measurement signals of the third tension measuring roller 79, the fourth tension measuring roller 87, the first tension measuring roller 77 and the second tension measuring roller 78 relating to the respectively measured mechanical web tension are supplied to the processing device 108. The processing device 108 processes the measurement signals or information. A control loop is present.

[0121] The mechanical tensions of the first and second outer webs measured by means of tension measuring rollers 77, 78, 79 or 87 are then compared and regulated if necessary. The processing device 108 determines a control variable from the control deviation or control difference, which acts accordingly on the controlled system 122.

[0122] In particular, the master outer width is defined as the adjustment variable. The slave outer width is automatically adjusted and regulated to the same value or with the same change, that is, it remains the same as the difference or deviation originally specified.

[0123] In reference Fig.11 In the case of FIG. 1 , the principle of the process of regulating the web tension difference in the laminating area of ​​the corrugator 1 is described more precisely. The corrugator 1 is here in operation.

[0124] First, the tension of the freely selectable master outer web is preset by means of the preset device 120. As described, the tension of the slave outer web is automatically adjusted or compensated.

[0125] Next, the curvature of the corrugated board sheet 102 is determined by the curvature determination device 105. As mentioned, this process can also be performed manually as an alternative.

[0126] Next, in step 124, it is checked whether the corrugated cardboard sheet 102 has or meets the required flatness in the longitudinal direction.

[0127] If the corrugated board sheet 102 has or meets the required flatness in the longitudinal direction, the tension of the single-sided laminated infinite length first corrugated board web 21, the single-sided laminated infinite length second corrugated board web 45 and / or the infinite length laminated web 72 is checked in step 125. As described, the tension measurement is performed by the third tension measuring roller 79, the fourth tension measuring roller 87, the first tension measuring roller 77 or the second tension measuring roller 78.

[0128] If the tension of the single-sided laminated infinite length first corrugated cardboard web 21 , the single-sided laminated infinite length second corrugated cardboard web 45 and / or the infinite length laminated web 72 is not appropriate, then the web tension level is adjusted in step 126 .

[0129] If the check in step 125 shows that the tension of the first single-sided laminated infinite length corrugated cardboard web 21, the second single-sided laminated infinite length corrugated cardboard web 45 and / or the infinite length laminated web 72 is normal, then as shown in step 127, there is no need to change the web tension level. The control process ends.

[0130] If the check in step 124 shows that the flatness of the corrugated cardboard sheet 102 in the longitudinal direction is not normal or does not meet the flatness requirement, the web tension difference will be adjusted by the processing device 108 in step 128 through the corresponding web tension difference control. This process will continue until the flatness of the corrugated cardboard sheet 102 in the longitudinal direction is normal or meets the flatness requirement. If necessary, the laminated web splicing device 67, especially its unfolding brake 69a or 71a, the first drive device 62 or the second drive device 65, will be operated accordingly for this purpose.

[0131] If the flatness of the corrugated board sheet 102 in the longitudinal direction is normal or satisfies the flatness, the correction data will be stored in the quality data memory 121. The correction data can be called by the preset device 120 when necessary.

[0132] When creating a new quality for which no empirical values ​​are yet available, the tension of the first outer web is preferably equal to the tension of the second outer web.

[0133] If there are loose edges on the first single-sided laminated infinite length corrugated cardboard web 21, a larger tension is required for the first single-sided laminated infinite length corrugated cardboard web 21. This is preferably set by the operator.

[0134] For example, if the first outer web has wrinkles, the tension of the second outer web may need to be changed and the operator may make a corresponding request. The tension of the second outer web may need to be increased or decreased.

[0135] If the laminated web 72 of infinite length or the first corrugated board web 21 of infinite length laminated on one side vibrates, it is necessary to increase the tension.

[0136] If the corrugated cardboard sheet 102 is bulging (bending upwards), the tension of the inner cover layer is reduced and / or the tension of the outer cover layer is increased, depending on the difference from the maximum or minimum limit value. Preferably, the value which differs more from the corresponding limit value is changed. In particular, the tension measured in the lamination area is used as the control variable. In other words, it is first determined whether the outer cover layer or the inner cover layer is closer to the limit value.

[0137] If the corrugated cardboard sheet 102 is concave (bent downwards), the tension of the inner cover layer is increased and / or the tension of the outer cover layer is reduced, depending on the difference from the maximum or minimum limit value. Preferably, the value with the largest difference from the corresponding limit value is changed. In particular, the tension measured in the lamination area is used as the control variable. In other words, it is first determined whether the outer cover layer or the inner cover layer is closer to the limit value.

[0138] The signal connection described here is designed as an infinite or finite connection, for example. Not all signal lines of the corrugator 1 are shown. The terms "downstream", "upstream", "arranged upstream", "arranged downstream" or other similar expressions used are usually based on the conveying direction of the corresponding web.

Claims

1. A system, a. A corrugator (1), the corrugator comprising i. a first corrugated board production device (2) for producing a first single-sided laminated corrugated board web (21); ii. a laminate web unfolding device (67) for unfolding a laminate web (72); iii. a joining device (88) arranged downstream of the first corrugated board production device (2) and the laminated web unwinding device (67) for joining the single-sided laminated first corrugated board web (21) with the laminated web (72) to form a double-sided laminated corrugated board web (91) having a first outer web (21, 72) and a second outer web (72, 21); and iv. at least one cutting device (97) arranged downstream of said joining device (88) for producing a corrugated board sheet (102) from said double-sided laminated corrugated board web (91); and b. A processing device (108) designed to automatically match the tension of the second outer web (72, 21) to the tension of the first outer web (21, 72) when necessary, so that the corrugated cardboard sheet (102) is flat or meets a flatness target value at least in the conveying direction of the corrugated cardboard sheet (102).

2. The system according to claim 1, characterized in that The system comprises a preset device (120) which is at least temporarily in signal connection with the processing device (108) and is used to preset the tension of the first outer web (21, 72).

3. The system according to claim 1 or 2, characterized in that: No tension is preset for the second outer web (72, 21).

4. A system according to any one of the preceding claims, characterised in that The first outer web (21, 72) forms a master outer web, and the second outer web (72, 21) forms a slave outer web, and master / slave tension adjustment is performed.

5. System according to any one of the preceding claims, characterized in that The processing device (108) has a tension comparison unit which compares a currently prevailing tension of the first outer web (21, 72) with a currently prevailing tension of the second outer web (72, 21).

6. A system according to any one of the preceding claims, characterised in that The tension difference between the current prevailing tension of the first outer web (21, 72) and the current prevailing tension of the second outer web (72, 21) can be adjusted.

7. A system according to any one of the preceding claims, characterised in that The processing device (108) adjusts the tension of the second outer web (72, 21) according to the tension of the first outer web (21, 72).

8. System according to any one of the preceding claims, characterized in that The tension difference between the current dominant tension of the first outer web (21, 72) and the current dominant tension of the second outer web (72, 21) is regulated.

9. System according to any one of the preceding claims, characterized in that The laminated web (72) or the first single-sided laminated corrugated board web (21) forms or has a first outer web, and the other web (72, 21) forms or has a second outer web.

10. System according to any one of the preceding claims, characterized in that The corrugator (1) comprises at least one laminated web tension changing device (69a, 71a) associated with the laminated web (72) and at least temporarily in signal connection with the processing device (108) in order to change the tension of the laminated web (72) when necessary.

11. System according to any one of the preceding claims, characterized in that The corrugator (1) comprises at least one first corrugated board web tension changing device (61, 62) associated with the single-sided laminated first corrugated board web (21) and at least temporarily in signal connection with the processing device (108) so as to change the tension of the single-sided laminated first corrugated board web (21) when necessary, wherein at least one first corrugated board web tension changing device (61, 62) is preferably arranged between the first corrugated board production device (2) and the joining device (88).

12. A system according to any one of the preceding claims, characterised in that The corrugator (1) comprises at least one laminated web tension measuring device (79, 87) associated with the laminated web (72) and at least temporarily in a signal connection state with the processing device (108), wherein at least one laminated web tension measuring device (79, 87) is first arranged between the laminated web unfolding device (67) and the joining device (88), preferably downstream of a laminated web preheating device (76) for preheating the laminated web (72).

13. A system according to any one of the preceding claims, characterised in that The corrugator (1) comprises at least one first corrugated cardboard web tension measuring device (77) associated with the single-sided laminated first corrugated cardboard web (21) and at least temporarily in signal connection with the processing device (108) so as to measure the tension of the single-sided laminated first corrugated cardboard web (21), wherein at least one first corrugated cardboard web tension measuring device (77) is firstly arranged upstream of the joining device (88), preferably downstream of a corrugated cardboard web preheating device (74) for preheating the single-sided laminated first corrugated cardboard web (21).

14. A system according to any one of the preceding claims, characterised in that The corrugator (1) comprises at least one curvature determination device (105) associated with the corrugated cardboard sheet (102) and at least temporarily in signal connection with the processing device (108) in order to determine the current prevailing curvature of the corrugated cardboard sheet (102).

15. A method for producing corrugated board, the method comprising the following steps: - producing the first single-sided laminated corrugated board web (21) by means of the first corrugated board production device (2); - unrolling the laminated web (72) from the laminated web unrolling device (67); - the single-sided laminated first corrugated board web (21) and the laminated board web (72) are joined by means of the joining device (88) arranged downstream of the first corrugated board production device (2) and the laminated board unwinding device (67) to form the double-sided laminated corrugated board web (91), wherein: The double-sided laminated corrugated cardboard web (91) comprises the first outer web (21, 72) and the second outer web (72, 21); - producing the corrugated board sheet (102) from the double-sided laminated corrugated board web (91) by means of at least one cutting device (97) arranged downstream of the joining device (88); and - if necessary, the tension of the second outer web (72, 21) is automatically matched to the tension of the first outer web (21, 72) by means of the processing device (108), so that the corrugated cardboard sheet (102) is flat at least in the conveying direction of the corrugated cardboard sheet (102) or meets a flatness target value.

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