Method for processing printed web and apparatus therefor

Abstract

The invention relates to a method for processing a web (4) printed with a printed image (6), in which the web (4) is fed to a cutting / slotting unit (14), by means of which the web (4) is processed at a plurality of processing positions (16) in the longitudinal direction (L), in which the web (4) has a width (B) upstream of the cutting / slotting unit (14), in which the actual dimension (I) of the width (B) is measured, in which the actual dimension (I) of the width (B) is measured. The cutting / slotting unit (14) is adjusted depending on the actual dimension (I) and the set dimension (S) of the width (B) in such a way that the processing position (16) is adapted to the printed image (6). A corresponding device (2) for such a treatment is also provided.

Description

Technical Field

[0001] The invention relates to a method for processing a web printed with a printed image, ie a printed web. The invention also relates to a corresponding device for this purpose. Background Art

[0002] An example of a web is a corrugated board web. This consists of several paper layers and can be printed if necessary. The corrugated board web is produced by a corrugating machine, at the end of which the corrugated board web is regularly assembled into individual boards, which are then further divided into individual sheets, such as folding boxes. For this purpose, the corrugated board web is usually cut longitudinally and transversely and thus divided into individual boards and sheets. If necessary, the corrugated board web can also be slotted longitudinally and / or transversely.

[0003] Often, the sheets should be printed with, for example, images, logos, decorations, etc. The corresponding printed images can be printed onto the individual sheets either after or before longitudinal and transverse cutting. In the latter case, the printed images are referred to as "preprints". In the case of preprints, the dimensional accuracy of the corrugated board web is problematic, since changes in the dimensions of the corrugated board web between printing and longitudinal and transverse cutting often result in the cuts produced during longitudinal and transverse cutting not being in optimal agreement with the print. The same problem applies to slotting.

[0004] EP 3 337 666 B1 describes a printing system in which, on the one hand, graphics are printed on a single substrate web for several different arrangements of corrugated board boxes to be lined with the web, and on the other hand, machine-readable images are printed representing corrugated board machine control information for manufacturing the boxes of the several different arrangements. The corrugated board machine control information includes adjustment marks representing position information for dynamically adjusting the position of the corrugated board and / or the cutting and folding tools for each of the different arrangements.

[0005] EP 3 360 639 B1 describes a method for producing corrugated board blanks, the method comprising cutting a corrugated board web with at least one form-bonded variable cutting tool, wherein a cutting line is introduced into the material web using the cutting tool, thereby generating a contour of the blank. A planning unit plans the position of the blank in the corrugated board web, wherein an expected shrinkage behavior of the corrugated board web, which has not yet been dimensionally stabilized by the form-bonded cutting tool, is taken into account and can be precalculated and adjusted by scaling the planned blank. Summary of the invention

[0006] In this context, an object of the present invention is to improve the processing of printed webs, in particular to improve the cutting and / or slotting of printed webs, in particular corrugated board webs. To this end, a correspondingly suitable method and apparatus are to be provided.

[0007] According to the invention, this object is achieved by a method having the features of claim 1 and a device having the features of claim 11. Advantageous embodiments, improvements and variants are the subject of the dependent claims. The detailed descriptions related to the method also apply to the device and vice versa. For the device, an advantageous design is that the device is configured to perform the method described below, in particular one or more steps thereof. For this purpose, the device particularly has a control unit configured accordingly for this purpose.

[0008] The method according to the invention is used for processing a web printed with a printed image. Printing is carried out in particular with a printing press and is not necessarily part of the method described here. The printed image includes in particular all content printed on the web (e.g. images, logos, decorations, texts, etc. for individual plates or sheets and / or control codes, adjustment marks, etc. for the device). In a suitable embodiment, printing is part of the method described here, but this is not mandatory. In a suitable embodiment, printing and processing are carried out inline. The web is in particular made of paper and is either a single layer made of only a single paper layer or a multilayer made of multiple paper layers. Preferably, the web is a corrugated board web and is therefore multilayer. Processing is usually carried out by a device, preferably by a corrugated board device, which will be used below, but without limiting the generality. Processing takes place after the printing of the printed image, i.e. there is a preprint in the process described below, in particular, the printed image is printed on a single paper layer even before it is connected with other paper layers in the corrugated board device to form a corrugated board web.

[0009] The web is fed to the cutting / grooving unit of the device and, by means of the cutting / grooving unit, the web is processed at a plurality of processing positions in the longitudinal direction, i.e. the positions of the cuts and / or grooves. The cutting / grooving unit refers in particular to a cutting and / or groove unit, i.e. a unit configured to cut the web or to groove the web or both. Accordingly, the cutting / grooving unit introduces one or more cuts and / or grooves, in particular longitudinal cuts and / or grooves, into the web, since the processing is carried out in the longitudinal direction. Without limiting the generality, the cutting and groove unit will be started with, with which the web is cut and grooved. The longitudinal direction corresponds to the conveying direction of the web through the device. The processing positions correspond to those positions along the web, at which the cutting / grooving unit introduces one or more cuts and / or grooves. The cuts and / or grooves are used in particular for assembling the corrugated board web into individual sheets and / or for forming the broken, folded or bent edges of the sheets or subsequent sheets, for example for forming them into boxes, boxes, etc. respectively. The introduction of cuts and / or grooves and thus the processing by the cutting / grooving unit is also referred to as "cutting", and the corresponding processing position is also referred to as "cutting".

[0010] In a suitable design, the cutting / slotting unit is arranged downstream of a so-called duplexer of the device. In the duplexer, several intermediate products for the corrugated board web are assembled into the actual corrugated board web. In particular, the duplexer also marks the end of the so-called "wet end" of the device (and is still part of the device), followed by the so-called "dry end" by which the corrugated board web is produced in particular into individual boards and then into individual sheets. The cutting / slotting unit is in particular part of the dry end of the device. Suitably, the web is even cut into several mutually separate partial webs (i.e. boards) (in the longitudinal direction) with the cutting / slotting unit. Therefore, the cutting / slotting unit is also called a longitudinal cutter. The partial webs are not necessarily identical, but can also differ from each other, in particular with respect to the printed image. Downstream of the cutting / slotting unit, the device suitably has a transverse cutter, which cuts the partial web in the transverse direction (i.e. perpendicular to the longitudinal direction) and thus subdivides it in particular into individual sheets. A divider is optionally arranged between the cutting / slotting unit and the transverse cutter. Furthermore, optionally, a short transverse cutter is arranged between the double-facer and the cutting / slitting unit, which short transverse cutter cuts the web in transverse direction like a transverse cutter, but with the purpose of separating waste or unwanted middle portions from the web.

[0011] Upstream of the cutting / slotting unit, the web has an actual width, also referred to as width for short. The actual width is the actual width of the web, measured in the transverse direction. Within the scope of the method, the actual dimension of the width is measured and the cutting / slotting unit is set as a function of the actual dimension of the width and the set dimension so that the processing position is matched to the printed image. In a suitable design, the actual dimension of the width is measured and a scaling factor is determined from this together with the set dimension in order to match the processing position to the width. In principle, it is advantageous to measure the width directly, so that the actual dimension is identical to the actual width. However, other dimensions, in particular the distance between two printed features of the printed image, or generally the distance between any features of the web, are also equally suitable as actual dimensions. In this case, the distance is measured in the transverse direction and therefore corresponds to a fraction of the width. It is important that the actual dimension in principle also changes as soon as the width changes. Therefore, by measuring the actual dimension, changes in the actual width can be identified.

[0012] In this case, the cutting / grooving unit is now set in such a way that the processing position is matched to the printed image according to the actual size and the set size. In a suitable design, more precisely, the cutting / grooving unit is set in such a way that the processing position is matched to the printed image according to the above-mentioned scaling factor. Thus, the cutting / grooving unit is adjustable and advantageously automatically adjusts according to the actual width (via the actual size) so that the cuts and / or grooves always fit the printed image exactly. To this end, in particular, the processing position, i.e. the layout of the cuts and / or grooves, is scaled by the scaling factor. Thus, variations in the actual width and thus actual undesired scaling of the printed image are compensated by a corresponding scaling of the cutting / grooving unit. Thus, the core idea of ​​the invention is in particular that the processing position of the cutting / grooving unit is matched to the actual printed image so that the resulting cuts and / or grooves better correspond to the actual printed image. In other words, the cutting is scaled so as to match the actual size of the printed image. Deviations of the resulting actual size of the plate / sheet from the predetermined set size, in particular from the order data, are acceptable. This is in contrast to the opposite approach of matching the printed image to a fixed processing position, i.e. positioning the cutouts and / or grooves exactly as specified in the order data (however, such an adjustment by scaling the printed image is also advantageous, as described further below). In this case, although the set size remains unchanged, the disadvantage is that the position of the printed image is not optimal if the size of the web changes. In particular, the cutting according to the external cutting size is generally no longer suitable for the printed image. For example, the web is divided into five similar partial webs by a cutting / slotting unit, i.e. the printed image has five similar images next to each other in the transverse direction, which images must be separated from each other accordingly and a certain width is specified in the order data as the set size. In the course of its travel to the cutting / slotting unit, the web undergoes an unexpected dimensional change, e.g. the web shrinks less than expected and now has an actual width that is greater than the set width, which is the same as the set size or results from the set size (and if appropriate, the expected dimensional change, but which does not actually occur). During the division process, this leads to parts of the image of one partial web being located on an adjacent partial web. For example, if one looks at a single sheet that has been formed into a folding box, the printed image is correspondingly shifted relative to the edges and frames of the folding box, i.e. the image edge and the cut edge do not match. Since the web is usually guided into the cutting / slotting unit in a centrally aligned manner, the corresponding errors increase outwards in the cross direction.

[0013] Thus, in contrast to EP 3 337 666 B1 mentioned at the outset, in this case a real scaling of the processing position and the cuts and / or grooves introduced thereby takes place, i.e. the actual dimensions of the sheet material change. In EP 3 337 666 B1, on the other hand, the tool is only positioned relative to the printed image or the corresponding marking in order to compensate for deviations in this respect, but the tool itself is not scaled. Thus, only a translation (slippage) of the web and the printed image is compensated, but not a scaling (shrinkage) of the web and the printed image.

[0014] In EP 3 360 639 B1, which is also mentioned at the beginning, the web can be printed before or after cutting. The cutting tool is then adjusted according to the expected shrinkage so that after all shrinkage operations are completed, the final corrugated board sheet has the desired dimensions. The blank is thus matched to the expected shrinkage process. In contrast, in this case, the blank is matched to the actual shrinkage process in such a way that the final dimensions (set dimensions) are not correctly maintained in some cases, but the blank is matched to the printed image so that the distance from the image edge to the cut edge matches.

[0015] In addition to adapting the processing position to the printed image, it is also advantageous in this case to take into account the expected shrinkage process, usually a dimensional change of the web. Accordingly, in the method, the (expected) dimensional change of the web is estimated in advance during the processing of the web, and the fact that the printed image is scaled, in particular enlarged, with the printing press is taken into account so that the change of the estimated dimensional change is compensated by adapting the processing position to the printed image. In this case, printing is in particular part of the method described here. The estimated dimensional change is firstly an expected dimensional change, which is not necessarily completely passed in the further running of the web through the device. Therefore, there are regular changes compared to the estimated dimensional change. Therefore, the method described here advantageously contains two compensation mechanisms for any dimensional change of the web, namely on the one hand for the estimated dimensional change and on the other hand for the actual dimensional change, in particular the change (or deviation) relative to the estimated dimensional change. First, the printed image itself is scaled from the outset according to the expected dimensional change, for example, the set size of the printed image is multiplied by the corresponding scaling factor. The expected dimensional change is based in particular on empirical values, which depend in particular on the specific order and the paper used. However, the expected dimensional changes generally do not take into account any changes in operation, i.e. dynamic dimensional changes caused, for example, by varying web speeds or due to deviations during drying or wetting of the web. The method described here now takes such dimensional changes into account in particular, since such dimensional changes are detected precisely by measuring the actual dimensions and then compensated for dynamically, preferably in real time, in particular automatically, by scaling the process position. Thus, a total of two levels of correction are achieved, wherein in a first level a first coarse static correction is performed by matching the printed image to the expected dimensional changes, in particular in the forefield, and then in a second level a second fine dynamic correction is performed by matching the process position to the printed image. In this case, the matching to the printed image is done indirectly by measuring the actual dimensions. Thus, in a first level, the offset is set, in particular by scaling the printed image, and then in a second level the offset is adjusted dynamically by scaling the cutting / slotting unit.

[0016] Alternatively or additionally, a further compensation mechanism is used to adjust the scaling of the printed image to the set size according to the actual size, so that the printed image matches the set size (adjustment by scaling the printed image). This adjustment takes place in particular before the web is fed to the cutting / slotting unit. This is particularly advantageous in an online operation in which the printing press and the corrugated board machine are operated together in-line. In this case, the printing press is in particular arranged upstream of the corrugated board machine or integrated upstream of the cutting / slotting unit in the corrugated board machine. Here, printing is also in particular part of the method described here. The disadvantage here is that the printed image downstream of the printing press cannot be further influenced and corrected by scaling the printed image before the actual width is measured. However, further correction is advantageously carried out by the arrangement of the cutting / slotting unit already described.

[0017] During operation, dimensional changes of the web occur in particular by wetting and / or drying the web one or more times within the device. Due to the supply and removal of moisture, the web expands or contracts. At the dry end, the contraction is regular relative to the wet end, which depends in particular on the web speed and therefore on the time required for the web to reach the cutting / slotting unit, and during which the web releases moisture to the environment.

[0018] The scaling factor is formed from the actual size and the set size, for example simply as a ratio of the actual size to the set size or in another suitable manner. Depending on the definition of the actual size and the set size, a prior conversion may be necessary in some cases. For example, if the actual size is the width of the entire web and the set size is the width of the partial webs, the actual size must first be divided by the number of partial webs or, conversely, the set size must be multiplied by the number of partial webs. In another example, the actual size is the distance between two printed features, which is then converted, for example, based on knowledge of the positions of the printed features (from the order data) into the width of the web and then starting from this width, as in the previous example. The set size is taken in particular from the order data for the processing web and is usually predetermined by the customer. The set size is a measure of the size that a single sheet / sheet should have at the end, for example, if the actual size is only the width of the entire web, then only the sum of the widths of the partial webs. In particular, the set size also specifies the processing positions, which are now scaled in the method described here to match the actual printed image.

[0019] In order to adapt the processing position to the printed image as best as possible, the actual dimensions are measured as close as possible to the cutting / grooving unit. In a suitable embodiment, the actual dimensions are measured up to 50 m, up to 40 m, up to 30 m, up to 20 m or up to 10 m, preferably up to 1 m, upstream of the cutting / grooving unit. In this way, possible dimensional variations are included as completely as possible, so that the adaptation to the actual printed image is particularly precise.

[0020] As already pointed out, various designs are possible and suitable for the actual dimensions, the important thing being that this allows conclusions to be drawn about the actual width and thus about the dimensions of the actual printed image.

[0021] In a first suitable embodiment, as described above, the actual size is simply the actual width. For example, the actual size is measured by web width or web edge detection; for this purpose, the device has a corresponding sensor unit. Particularly advantageous embodiments are those in which the web has at least two layers of different widths, so that the actual width of the web is determined by measuring the respective widths of the two layers and comparing them with each other, thereby determining the dimensional change.

[0022] In a second suitable design, the actual size is the distance between two printed features of the printed image. In this design, the printed image is therefore directly analyzed in order to detect any dimensional changes of the web and the printed image. Initially, which specific printed features are used is secondary. However, it is advantageous if they are as far apart as possible along the width of the web, i.e. there is as great a distance as possible between two printed features in the transverse direction. This ensures that there is sufficient resolution when measuring the actual size to detect usually small dimensional changes. The expected dimensional changes are usually about 0.7%, which vary less in operation, usually at most 0.3% (in both directions, i.e. + / - 0.3%), in particular about 0.2%. For example, for a web width of 2800 mm, these are only about 5 to 6 mm, i.e. starting from the center of the web and not more than 3 mm on either side. Thus, a distance corresponding to at least 50% of the web width is advantageously formed between the two printed features. Thus, the two printed features are particularly regularly located on different partial webs, preferably on the two outermost partial webs, i.e. once on the operating side of the device and once on the drive side of the device. Depending on the measurement resolution, too small a distance is not suitable.

[0023] In principle, all features present in the printed image are suitable as printed features. Suitable printed features are longitudinal lines (e.g. for web edge measurement), logos, images or image elements (e.g. edges, frames), codes (e.g. QR or barcodes), or as part of the printing of the board / sheet and / or for controlling devices (so-called control codes). It is particularly suitable to use printed features which are already present in any case and do not require additional printing. For example, control codes for subsequent transverse cutters are particularly suitable as printed features. These control codes serve in particular to activate the transverse cutters so that a cross section is produced at a specific position relative to the control code.

[0024] In an advantageous design, the actual size is determined by two sensors, which at the same time also regulate the cutting / slotting unit as a whole relative to the web run entering the cutting / slotting unit. The web run particularly refers to the position of the web relative to the transverse direction. The two sensors are part of a sensor unit, which in turn is part of the device. The web does not necessarily enter the cutting / slotting unit at a specific position, but can be displaced in the transverse direction depending on the way the web is fed to the device. In particular, when the device processes webs with a width less than the maximum width that the device can process, the web can run in the center or closer to the operating side of the device or closer to the drive side of the device. Therefore, tracking of the cutting / slotting unit is necessary in order to adapt the processing position as a whole to the general run of the web and initially independent of size changes. For this purpose, the device has the above-mentioned two sensors, with which the web run is measured in order to correctly position the cutting / slotting unit in the transverse direction according to the two sensors. The two sensors are now also used to measure the actual size. Accordingly, the sensors are optionally configured as appropriate, for example for identifying the printing features.

[0025] The exact design of the sensor unit and its sensors and the way in which the printed features (or web width) are identified are of secondary importance for the method described here; what is important is that the actual dimensions are measurable, regardless of how they are defined. As an alternative to the described sensors for web travel, in principle equally suitable sensor units are usually used immediately after the printing unit that prints the printed image onto the web, in order to check the same printed image. A corresponding sensor unit is also suitable for identifying printed features, but is positioned for this purpose as close as possible to the cutting / slitting unit.

[0026] In order to produce the cuts and / or grooves at the processing locations, the cutting / grooving unit has a plurality of processing bodies. These processing bodies are arranged in particular in the transverse direction. The processing bodies are in particular configured for mechanically processing the web material so as to introduce the cuts and / or grooves into the web material by mechanical action. The respective processing body has, for example, a roller pair with two rollers and a corresponding cutting blade or groove profile. Preferably, the processing bodies can be adjusted relative to one another, and the cutting / grooving unit is adjusted by adjusting the processing bodies relative to one another. In other words: by correspondingly adjusting the processing bodies relative to one another, for example appropriately increasing or reducing their distance in the transverse direction, the processing locations are scaled and matched to the printed image.

[0027] In a preferred design, the processing bodies are configured for parallel positioning and can be adjusted separately from each other for this purpose. In particular, the cutting / grooving unit has a separate adjustment mechanism for each processing body (e.g., each with a spindle), and the adjustment mechanisms can be controlled independently of each other. This is in contrast to serial positioning, which is generally not suitable for the method described here, because in this case, only a single adjustment mechanism is used for multiple processing bodies.

[0028] The device according to the invention is used for processing a web printed with a printed image. The device has a cutting / slotting unit to which the web is fed so as to be processed at a plurality of processing positions in the longitudinal direction. Upstream of the cutting / slotting unit, the web has an actual width. The device further comprises a sensor unit configured to measure an actual dimension of the actual width, and a control unit configured to determine a scaling factor according to the actual dimension and a set dimension so as to match the processing position to the actual width. The control unit is then further configured to adjust the cutting / slotting unit according to the scaling factor so that the processing position matches the printed image. The above statements apply analogously to the device. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In the following, embodiments of the present invention are explained in more detail with reference to the accompanying drawings, wherein:

[0030] Figure 1 The device is shown;

[0031] Figure 2 A flow chart of the method is shown;

[0032] Figure 3 A web having a printed image is shown;

[0033] Figure 4 Shows the size change after Figure 3 of web;

[0034] Figure 5 Shown after matching the processing position to the printed image Figure 4 of web;

[0035] Figure 6 The distance between two printed features as actual size is shown;

[0036] Figure 7 Shows Figure 1 The cutting / grooving unit of the device. DETAILED DESCRIPTION

[0037] Figure 1 An embodiment of an apparatus 2 for processing a web 4 is shown. The web 4 is printed with a printed image 6, which includes all the content printed on the web 4 (e.g., images, logos 8, decorations 10, text, control codes 12, adjustment marks, etc.). Printing is not necessarily part of the method for processing a web 4 described here. In the embodiment shown, the web 4 is made of paper and corrugated board webs and is therefore multi-layered. In this case, the apparatus 2 is an example of a corrugated board apparatus, but the following description is similarly applicable to other apparatuses 2 and webs 4. In any case, the processing of the web 4 described here occurs after the printed image 6, i.e., a preprint is present during the processing.

[0038] The web 4 is fed to a cutting / slotting unit 14 of the apparatus 2 and, with the aid of the cutting / slotting unit 14, is processed at a plurality of processing locations 16, i.e. cutting and / or slotting locations, in the longitudinal direction L. The cutting / slotting unit 14 introduces one or more cuts and / or grooves into the web 4. Without limiting the generality, starting from the cutting and slotting unit 14, the web 4 is cut and slotted with the aid of the cutting and slotting unit 14. The longitudinal direction L corresponds to the conveying direction of the web 4 through the apparatus 2. The processing locations 16 correspond to those locations along the web 4 at which the cutting / slotting unit 14 introduces one or more cuts and / or grooves for manufacturing the corrugated board web into individual sheets 26 and for forming broken, folded or bent edges of the sheets 26 and of the subsequent sheets 18.

[0039] In the design shown here, the cutting / grooving unit 14 is arranged downstream of a so-called double facing machine 20, in which several intermediate products for a corrugated board web are assembled into the actual corrugated board web. The double facing machine 20 also marks the end of the so-called "wet end" 22 of the apparatus 2, followed by the so-called "dry end" 24, by which the web 4 is assembled into individual panels 26 and finally into sheets 18. The cutting / grooving unit 14 is part of the dry end 24. In this case, the web 4 is cut by the cutting / grooving unit 14 into several mutually separate partial webs (i.e., panels 26). Downstream of the cutting / grooving unit 14, the apparatus 2 also has a transverse cutter 28, which cuts the partial web in the transverse direction Q and thereby divides it into individual sheets 18. Optionally, a divider 30 is arranged between the cutting / grooving unit 14 and the transverse cutter 28. Furthermore, optionally, a short transverse cutter 32 is arranged between the double facing machine 20 and the cutting / grooving unit 14.

[0040] Upstream of the cutting / slotting unit 14, the web 4 has an actual width B, also referred to as width for short. The actual width B is the actual width of the web 4 and is measured in the transverse direction Q. In the context of the method, the actual dimension I of the actual width B is measured and from this together with the set dimension S a scaling factor F is determined in order to match the processing position 16 to the actual width I. The cutting / slotting unit 14 is then set according to the scaling factor F in such a way that the processing position 16 matches the printed image 6. This is done in Figure 2 As an example, the flow chart of FIG. 1 shows the process of FIG. 14 . Thus, the cutting / grooving unit 14 is adjustable and automatically adjusts itself according to the actual width B (by means of the actual dimension I) so that the cuts and / or grooves always match the printed image 6 exactly. For this purpose, the processing positions 16 , i.e. the layout of the cuts and / or grooves, are scaled by the scaling factor F. Thus, changes in the actual width and thus actually undesired scaling of the printed image 6 are compensated by a corresponding scaling of the cutting / grooving unit 14 .

[0041] In general, the processing position 16 of the cutting / grooving unit 14 is adapted to the actual printed image 6, thereby accepting the resulting deviations of the actual dimensions of the sheet 26 from the predetermined set dimensions S from the order data 34. This is in contrast to the opposite approach of adapting the printed image 6 to a fixed processing position 16, i.e. positioning the cuts and / or grooves exactly as specified in the order data 34. In this case, the cuts and / or grooves are usually no longer adapted to the printed image 6. This is in contrast to the method ... no longer adapted to the printed image 6. This is in contrast to the method of adapting the printed image 6 to a fixed processing position 16, i.e. positioning the cuts and / or grooves exactly as specified in the order data 34. In this case, the cuts and / or grooves are no longer adapted to the printed image 6. This is in contrast to the method of adapting the printed image 6 to a fixed processing Figure 3-5, which shows a web 4 and a processing position 16 in a plan view of the web 4. There, the web 4 is divided into five similar partial webs by the cutting / slitting unit 14, that is, the printed image 6 has five adjacent similar images in the transverse direction Q, which must be separated from each other accordingly, and in the order data 34, the predetermined width is specified as the set size S. This ideal situation is as shown in FIG. Figure 3 , where the set dimension S matches the printed image 6. However, during its travel to the cutting / slitting unit 14, the web 4 undergoes an unexpected dimensional change, for example, the web 4 shrinks less than expected and now has an actual width B that is greater than the set width resulting from the set dimension S (and optionally, an expected dimensional change that did not actually occur). Figure 4 , and during the segmentation process, parts of the image of one sheet 26 are located on an adjacent sheet 26. For example, if a single sheet 18 that has been formed into a folding box is observed, the printed image 6 is correspondingly displaced relative to the edges and frame of the folding box, i.e. the image edge and the cut edge do not match. Figure 3-5 As shown, the web 4 is generally guided into the cutting / slitting unit 14 in a centrally aligned manner, so that the corresponding error increases outwardly in the transverse direction Q, as shown in FIG. Figure 4 This can be clearly seen in the figure. The method described here is based on the scaling factor F and Figure 4 Start adjusting the cutting / slotting unit 14 accordingly, scaling the processing position 16 to the actual printed image 6, and then Figure 5 , where the cutouts and recesses are again optimally adapted to the printed image 6 .

[0042] In addition to the described adaptation of the processing position 16 to the printed image 6, in this case, an expected dimensional change of the web 4 is also taken into account. Accordingly, in the method, a dimensional change of the web 4 is estimated (anticipated) in advance when the web 4 is processed in the device 2, and the fact that the printed image 6 is scaled (e.g. enlarged) is taken into account, so that a change in the estimated dimensional change is then compensated by the already described adaptation of the processing position 16 to the printed image 6. The estimated dimensional change is first of all an expected dimensional change, which in the further run of the web 4 may not actually completely pass through the device 2, and therefore, despite this being taken into account, will appear at the cutting / slitting unit. Figure 4s the situation shown. This is due to a variation compared to the estimated dimensional variation. The method described here therefore advantageously comprises two compensation mechanisms for any dimensional variation of the web 4, namely on the one hand for the estimated dimensional variation and on the other hand for the actual dimensional variation, in particular for the variation (or deviation) relative to the estimated dimensional variation. Firstly, the printed image 6 itself is scaled from the outset according to the expected dimensional variation, e.g. the set size S of the printed image 6 is multiplied by a corresponding scaling factor (not the scaling factor F already mentioned). The expected dimensional variation is usually based on empirical values ​​which depend on the specific order and the paper used and which usually do not take into account variations in operation, i.e. dynamic dimensional variations caused, for example, by varying web speeds or by deviations during drying or wetting of the web 4. The method described here now takes such dimensional variations into account in particular, since such dimensional variations are detected precisely by measuring the actual size I and are then automatically compensated for dynamically and in real time by scaling the processing position 16. Thus, a total of two stages of correction are achieved, wherein in a first stage a first coarse static correction is performed by previously adapting the printed image 6 to the expected dimensional changes, and then in a second stage a second fine dynamic correction is performed by adapting the processing position 16 to the printed image 6, as in combination with Figure 5 described.

[0043] The scaling factor F is formed from the actual dimension I and the set dimension S, for example simply as a ratio of the actual dimension I to the set dimension S or in another suitable manner. The set dimension S is taken from the order data 34 for the processed web 5 and is usually predetermined by the customer. The set dimension S is a measure of the size that the individual plates 26 or sheets 18 should have at the end, for example simply the sum of the widths of the partial webs 26 if the actual dimension I is only the width B of the entire web. The set dimension S also specifies the processing position 16, which is now scaled in the method described here to match the actual processing image 6.

[0044] In order to adapt the processing position 16 to the printed image 6 as best as possible, the actual dimension I is measured as close as possible to the cutting / grooving unit 14, for example at most 10 m or even only at most 1 m upstream of the cutting / grooving unit 14. In principle, various configurations are possible and suitable for the actual dimension I; what is important is that this allows conclusions to be drawn about the actual width B and thus about the size of the actual printed image 6.

[0045] In a first possible embodiment, the actual dimension I is simply the actual width B of the web 4. For example, the actual dimension I is measured by web width or web edge detection; for this purpose, the device 2 has a corresponding sensor unit 36. In a second possible embodiment, the actual dimension I is the distance between two printed features 38 of the printed image 6, for example Figure 6As shown. In this design, the printed image 6 is therefore directly analyzed in order to detect any dimensional changes of the web 4 and the printed image 6. Initially, it is secondary which specific printed features 38 are used. However, they are separated as far as possible along the width B of the web 4, i.e. there is as great a distance as possible between two printed features 38 in the transverse direction Q. Figure 6 In the embodiment of the present invention, the spacing is at least 50% of the width B and the two printed features 38 are even located on different partial webs 26 , in particular on the two outermost partial webs 26 .

[0046] In principle, all features present in the printed image 6 are suitable as printed features 38, such as the already mentioned logos 8, decorations 10 and control codes 12, as well as printed features 38 which are usually already present and do not require additional printing, such as control codes 12 for a subsequent transverse cutter 28.

[0047] In this case, the actual dimension I is determined by two sensors, which at the same time also regulate the cutting / slotting unit 14 relative to the web run entering the cutting / slotting unit 14. The web run denotes the position of the web 4 relative to the transverse direction Q. The two sensors are part of a sensor unit 36 ​​for tracking the cutting / slotting unit 14 so that the processing position 16 as a whole is matched to the overall web run and initially independent of dimensional variations. To this end, the web run is measured with the sensors, and based thereon the cutting / slotting unit 14 is then correctly positioned in the transverse direction Q. Furthermore, the two sensors now additionally measure the actual dimension I. Accordingly, the sensors are configured to detect said printed features 38 or width B.

[0048] In order to produce the cuts and / or grooves at the processing location 16, the cutting / grooving unit 14 has a plurality of processing bodies 42, such as Figure 7 As shown. These processing bodies 42 are arranged along the transverse direction Q and are configured to mechanically process the web 4 so as to introduce cuts and / or grooves in the web 4 by mechanical action. The respective processing body 42 has, for example, a roller pair having two rollers and corresponding cutting blades or groove profiles. The processing bodies 42 can be adjusted relative to each other, and the cutting / grooving unit 14 is adjusted by adjusting the processing bodies 42 relative to each other. In other words, by correspondingly adjusting the processing bodies 42 relative to each other, for example appropriately increasing or decreasing their distance in the transverse direction Q, the processing position 16 is scaled and matched to the printed image 6. Figure 7 In the embodiment of the present invention, the processing bodies 42 are configured for parallel positioning and can be adjusted separately from each other for this purpose. The cutting / grooving unit 14 has a separate adjustment mechanism 44 for each processing body 42 (e.g., each having a spindle), and the adjustment mechanisms 44 can be controlled independently of each other. This is in contrast to serial positioning, in which only a single adjustment mechanism is used for multiple processing bodies 42.

[0049] The device 2 also has a control unit 46 which is configured to determine a scaling factor F from the actual size I and the set size S in order to then match the processing position 16 to the actual width B as described above. The control unit 46 is then also configured to adjust the cutting / slotting unit 14 according to the scaling factor F so that the processing position 16 matches the printed image 6.

[0050] Reference numerals list

[0051] 2 Equipment

[0052] 4 sheets

[0053] 6. Printing images

[0054] 8 Logo

[0055] 10. Decoration

[0056] 12 Control Code

[0057] 14 cutting / grooving units

[0058] 16 Processing Locations

[0059] 18 sheets

[0060] 20 double-sided machine

[0061] 22 wet end

[0062] 24 Dry end

[0063] 26 Plates (partial webs)

[0064] 28 Transverse cutter

[0065] 30 Divider

[0066] 32 short transverse cutter

[0067] 34Order data

[0068] 36 sensor units

[0069] 38 Printing Features

[0070] 42 Processing Body

[0071] 44 Adjustment mechanism

[0072] 46Control Unit

[0073] B Actual Width

[0074] F scaling factor

[0075] I Actual size

[0076] L vertical

[0077] QHorizontal

[0078] S sets the size.

Claims

1. A method for processing a web (4) printed with a printed image (6), − Among them, The web (4) is fed to a cutting / slitting unit (14) by means of which the web (4) is processed by means of a plurality of processing positions (16) in the longitudinal direction (L), − wherein the web (4) has a width (B) upstream of the cutting / slotting unit (14), − where the actual dimension (I) of the width (B) is measured, − wherein the cutting / slotting unit (14) is adjusted according to the actual size (I) and the set size (S) of the width (B) so that the processing position (16) matches the printed image (6).

2. The method according to claim 1, in, A dimensional change of the web (4) is estimated in advance during processing and the printed image (6) is printed in a scaled manner taking into account so that changes in the estimated dimensional change are compensated by matching the processing position (16) to the printed image (6).

3. The method according to claim 1 or 2, in, The printed image (6) is scaled to the set size (S) according to the actual size (I), so that the printed image (6) matches the set size (S).

4. The method according to any one of claims 1 to 3, in, The actual dimension (I) is measured at most 10 m upstream of the cutting / grooving unit (14).

5. The method according to any one of claims 1 to 4, in, The actual size (I) is the distance between two printed features (38) of the printed image (6).

6. The method according to any one of claims 1 to 5, in, The actual dimension (I) is the width (B).

7. The method according to any one of claims 1 to 6, in, The actual dimension (I) is determined by two sensors which also regulate the cutting / slotting unit (14) as a whole with respect to the web run entering the cutting / slotting unit (14).

8. The method according to any one of claims 1 to 7, in, The cutting / grooving unit (14) for producing cuts and / or grooves has a plurality of processing bodies (42) which can be adjusted relative to one another. Therein, the cutting / grooving unit (14) is adjusted by adjusting the processing bodies (42) relative to each other.

9. The method according to claim 8, in, The processing bodies (42) are configured to be positioned in parallel and can be adjusted separately from one another for this purpose.

10. The method according to any one of claims 1 to 9, in, The web (4) is a corrugated cardboard web.

11. A device (2) for processing a web (4) printed with a printed image (6), − comprising a cutting / slotting unit (14), to which the web (4) is fed in order to process the web (4) at a plurality of processing positions (16) in the longitudinal direction (L), − Among them, The web (4) has a width (B) upstream of the cutting / slitting unit (14), − comprising a sensor unit (36) configured to measure the actual dimension (I) of said width (B), − comprising a control unit (46) configured to adjust the cutting / slotting unit (14) according to the actual size (I) and the set size (S) of the width (B) so that the processing position (16) matches the printed image (6).

Images