EP3645226A1

EP3645226A1 - Cross-cutting device and method for stabilizing a cutting edge during crush cutting

Info

Publication number: EP3645226A1
Application number: EP19740497.3A
Authority: EP
Inventors: Mathias Borg; Thorsten Gädtke; Frank Herpell
Original assignee: BW Papersystems Hamburg GmbH
Current assignee: BW Papersystems Hamburg GmbH
Priority date: 2018-07-13
Filing date: 2019-07-02
Publication date: 2020-05-06
Anticipated expiration: 2039-07-02
Also published as: ES2908857T3; JP7125536B2; JP2021531985A; DE102018122005A1; EP3645226B1; WO2020011599A1; CN112703096B; CN112703096A

Abstract

The invention relates to a cross-cutting device (1), particularly for cutting or cross-severing a running material web (2), preferably made of paper, cardboard, plastic and/or metal, into sheets (3), having a knife drum (5) as a rotatable cutting device, which is rotatable about a rotation axis extending crosswise to the material web (2) and the conveying direction thereof, wherein the knife drum (5) has at least one knife (8) extending in the axial direction of the knife drum (5) and rotating together with the knife drum (5), with a corresponding anvil drum (6), which is rotatable about a rotation axis extending crosswise to the material web (2) and the conveying direction thereof, wherein the anvil drum (6) is preferably arranged vertically under the knife drum (5), wherein a crush cut is carried out in a cutting line when a knife (8) of the knife drum (5) contacts the anvil drum (6), the knife drum (5) having at least one hold-down (9) on the circumference thereof before the knife (8) in the transport direction (10) of the material web (2). According to the invention, the hold-down (9) has a distance from the knife (8) and/or a radial extension such that the material web (2) contacts the hold-down (9) during crush cutting and is arched by the hold-down (9) in the direction toward the anvil drum (6).

Description

Cross cutting device and method for stabilization

a cut edge when squeezing

The invention relates to a cross cutting device, in particular for cutting or cross cutting a running web of material, preferably Pa pier, cardboard, plastic and / or metals in sheets, with a rotary drum about a transverse to Ma material web and its conveying direction of rotation axis as a rotating cutting device, wherein the knife drum has at least one knife drum extending in the axial direction of the knife drum, with a corresponding rotary drum rotating about an axis of rotation transverse to the material path and its conveying direction Contact of a knife of the knife drum with the anvil drum a squeeze cut is carried out in a cutting line, the knife drum having at least one hold-down device in the transport direction of the material web in front of the knife on its circumference. In addition, the invention relates to a method for stabilizing a cut edge in a crimp cut in a cross cutting device.

Cross cutting devices, consisting of a knife drum and a cor responding anvil drum that perform a squeeze cut, are known from the prior art. The running material web is cut into sheets in such a way that a knife of the knife drum comes into contact with the anvil drum. In order to ensure a perfect cut, the knife can preferably pass the anvil essentially without play. In the transport direction of the sheets, the cross cutter is usually followed by a guide plate, which is used for receiving and further transporting the sheets. The baffle is usually arranged after the anvil drum, forming a small gap. A gap remaining between the guide plate and the anvil drum cannot be avoided by design, since a contact between the anvil drum and the guide plate can lead to damage to the guide plate and / or the anvil drum.

Often the cut edge of the material web or a cut sheet adheres to the surface of the anvil drum after the cut and runs with the anvil drum in such a way that the transfer to the guide plate can be prevented or significantly disturbed. The leading edge of the material web can, for example run into the gap between the anvil drum and the baffle. The corresponding sheet is then not fed to the further processing process, which can lead to disruptions to the operational sequence. However, it can also happen that the front cutting edge of the material web adheres to the knife of the knife drum and runs with the knife drum. This undesired behavior of the material web or the sheet can also lead to faults which can result in a stop of the cross-cutting device and a manual correction of the sheet position.

The object of the present invention is to provide a cross cutter in which a running along of the leading edge of the sheet with the knife drum and / or the anvil drum is effectively prevented. At the same time, the cut quality is to be improved. In addition, a method is to be provided that overcomes the disadvantages mentioned above and fulfills the tasks described in this paragraph.

The above object is achieved by a cross cutting device with the features of claim 1 and by a method with the features of claim 10. The subclaims give advantageous refinements of the invention.

Experiments carried out within the scope of the invention have shown that the cut quality of the cross-cutting device strongly depends on the position of the material web relative to the knife and the anvil drum. According to the invention, since the hold-down device of the cross-cutting device is at a distance from the knife and / or a length or a radial extension in the direction of the anvil stream mel (based on the position of the hold-down device during the squeeze cut), the material web is in contact with the hold-down device during the squeeze cut stands and is arched by the hold-down in the direction of the anvil drum. The derie holder is arranged on the circumference of the knife drum in the transport direction of the material web in front of the knife. The material web is fed to the transverse cutting device via a baffle and cut into sheets. The material web is pressed immediately before and during the cut down towards the Am drum. After the cut has been made, the holding-down device continues to press the front area of the material web downward in the direction of the anvil drum. This prevents the leading edge from running along with the measuring drum. On the other hand, the material web is directed towards the Boss drum arched and thereby stabilized its position during the cut, which results in a significantly improved cutting result.

The invention is therefore based on the idea of temporarily arching the material web before and during the cut and thereby stabilizing it in particular during the cut. The cut quality is improved by the higher stability of the material web. Furthermore, the hold-down device effectively prevents the material web from running along with the knife drum.

A knife drum can have a single knife, which preferably extends essentially over the entire length of the knife drum. Such a knife drum makes a cut with every complete revolution. Alternatively, a knife drum can also have a plurality of knives which extend over the entire length of the knife drum. A number of cuts corresponding to the number of knives is then carried out per revolution of the knife drum. In the latter case, the corresponding transverse cutting device also has a plurality of cutting lines and thus in any case also a number of hold-down devices. It is also possible that a knife extending over the entire length of the drum is divided into a plurality of knife sections or knife segments. The knife segments can then be replaced independently of one another and / or adapted to the width of the material web.

Advantageously, the web of material is pressed by the hold-down device against the anvil drum during the squeeze cut and already lies directly against the anvil drum before the cut. The hold-down acts against the one, preferably upper, flat side of the material web and presses the material web with the other flat side against the anvil drum. The material web is thus clamped between the hold-down device and the anvil drum and guided with the movement of the two drums during the cut. The resulting curvature in the material web and the clamping of the arch between the anvil drum and the hold-down device cumulatively improve the stability of the material web during cutting. In this way, a reproducible cut, in particular a reproducible and stable position of the material web during the cut is generated, whereby the cut quality is improved. In an advantageous embodiment of the invention, the anvil drum has at least one lifter in the transport direction of the material web before the cutting line to stabilize the material web during the cutting process. The material web is fed to the cross cutting device via a guide plate, lies at least in regions on the lifter and is preferably pressed in the transport direction by the hold-down device S-shaped in the direction of the anvil drum. The material web preferably lies in the area of the hold-down device and the cutting line when cutting on the anvil drum. The S-shaped curvature significantly improves the stabilization of the material web, which has a positive influence on the cut quality and the reproducibility of the cut. This has confirmed extensive tests carried out within the scope of the invention.

The lifter also has the function of preventing the front edge or the front area of the material web from running along with the anvil drum. If the two drums continue to turn after cutting the material web, the distance between the hold-down device and the anvil drum is increased in such a way that the hold-down device no longer presses the material web onto the anvil drum and / or in the direction of the anvil drum. Due to the lack of resistance, the material web is raised radially by the lifter and then no longer lies on the anvil drum in the area of the front edge. The curvature of the material web decreases during this process until the material web is no longer or only slightly arched. The cutting edge itself is then neither on the lifter nor on the anvil drum. A running of the leading edge area of the material web with the anvil drum can be effectively prevented in this way.

In an advantageous manner, the lifter is arranged at least essentially in front of the hold-down device in the movement regime of the interaction of the knife drum and anvil drum in the transport direction of the material web. The movement regime of the interacting knife and anvil drums describes the coordinated rotary movement of the knife drum and the anvil drum and the resulting interaction of the lift and the hold-down device. In this case, the lifter and the hold-down device preferably act simultaneously against different flat sides of the material web during the squeeze cut. The lifter is preferably spaced from the hold-down device in the circumferential direction of the drum. This means that the lifter on average in transport Direction of the material web or in the circumferential direction of the drums from the cutting line is further apart than the hold-down device. When the two drums rotate in opposite directions, the lifter and the hold-down device come into contact with the material web in such a way that it lies at least in regions on the hold-down device and is arched by the interaction of the hold-down device and the lifter. In the area of the cutting line, the material web is preferably on the anvil drum during the cut. The curvature of the material web in the cut can be influenced by the choice of the distance in the circumferential direction between the lifter and the hold-down device. The distance between the lifter and the hold-down device is preferably at least 1 mm, more preferably at least 2 mm.

In a preferred embodiment, a plurality of spaced-apart lifters and / or hold-downs spaced apart from one another is provided transversely to the material web and its transport direction. The spaced apart lifters segment a lifting area, spaced apart hold-downs a hold-down area. Due to the plurality of spaced apart lifters and / or hold-downs, a uniform curvature of the material web can be generated over the entire width of the material web. This contributes in particular to an increased stabilization of the material web in the cut and to an improved cut quality. Advantageously, the lifter and hold-down device can be arranged offset to one another in the transport direction of the material web. The curvature can be done in a material-friendly manner.

Preferably, the knife drum on its circumference at least one Niederhal ter in the transport direction of the material web after the knife. By arranging an additional hold-down device in the transport direction after the knife, the material web is pressed on average by the hold-down devices before and after the knife in the direction of the anvil drum. The material web is thus stabilized on both sides of the knife. In this way, the cut quality can be further improved.

The hold-down device and the lifter can be arranged to mesh with one another at least in edge areas in a squeeze cut. The hold-down device and the lifter are then spaced apart from one another transversely to the transport direction and overlap in the edge regions facing one another in the transport direction. Provided that the hold-down device and lifter at least during the cutting process temporarily overlap or comb in edge areas, on the one hand an advantageous bend or curvature of the material web in the transport direction and on the other hand also a curvature of the material web transverse to the transport direction is achieved. If a plurality of spaced apart lifters and hold-down devices is provided transversely to the material web, a wel-shaped curvature of the material web can be produced transversely to the transport direction. Curvatures of the material web that are produced in the direction of transport and across there overlap and form a complex, three-dimensional curvature in the material web. Due to the aforementioned curvature, the material web is reproducibly fixed in its position in a particularly stable manner and a particularly advantageous cut quality is produced.

More preferably, the lifter and / or the hold-down device consist of an elastic material, for example of a foam, a rubber material or an elastomer material. The passage of the material web can be improved in this way. Due to the elastic behavior of the lifter and the hold-down device, the curvature in the material web is created in a way that is gentle on the material. This can effectively prevent the surfaces of the material web from being damaged or otherwise negatively influenced. Due to their elastic material, the lifter and the hold-down device can compensate for changes in the material web, for example when using a thicker material web, without damaging the material web or negatively influencing the process. The lifter can also be made of a rigid material. The lifter can, for example, be milled into the anvil, the lifter in this case having the same material as the anvil. Thus, the lifters and hold-downs are suitable for a variety of possible material web properties to be processed.

The lifter and the hold-down device can each be formed as a separate element and can be exchanged and attached to the knife drum or the anvil drum. The lifter and the hold-down device can be connected in a simple manner to the anvil or measuring drum by means of a screw connection or jamming and thus can be easily changed and / or exchanged. This means that the lifter and the hold-down device can be selected to suit the requirements of a process or a material web and then mounted on the respective drum. Alternatively, the lifter and the hold-down device cannot be connected to the drum interchangeably. The lifter and the hold-down device can, for example, be made in one piece with be connected to the respective drum or permanently connected to it, for example glued. It is not excluded that the lifter and / or the hold-down device is adjustable in height. In this context, height-adjustable means that the lifter and / or the hold-down device can be designed to be movable and / or adjustable in the radial direction. In this way, a lifter and / or a hold-down device can be used for different applications and aligned in the radial direction according to the requirements. A radial adjustment can be done hydraulically or mechanically, for example, using adjusting screws. Appropriate devices and methods for the radial adjustment of an element are known to the person skilled in the art.

Preferably, several hold-down devices are provided transversely to the transport direction, where the total hold-up of the hold-down device in the longitudinal direction of the measuring drum, i.e. the sum of the individual lengths, at least 5% of the length of the knife drum, preferably at least 10%, preferably 15% to 45%, can amount to. The hold-down devices are preferably evenly spaced from one another in the longitudinal direction of the knife drum. A corresponding arrangement of the hold-down devices creates a uniform curvature in the material web across the width of the material web. The material web is also fixed evenly during the cut, so that the cut quality along the cut is of a consistently high quality.

Advantageously, several lifters are provided, the accumulated extension of the lifters in the longitudinal direction of the anvil drum, i.e. the sum of the individual lengths, at least 2%, preferably at least 5% of the length of the anvil drum, preferably at least 10%, preferably 15% to 45%. The lifters are preferably evenly spaced from one another in the longitudinal direction of the anvil drum. The alignment of the lifter leads to a uniform curvature of the material web and thus to a uniform fixation of the material web in the cut. At the same time, it is ensured that the front area of the material web is raised radially after the cut and is prevented from running with the anvil drum.

If several lifters and several hold-down devices are provided, lifters and hold-down devices alternate in the direction transverse to the material web, so that there is an alternating arrangement of lifters and hold-down devices. In a further advantageous embodiment of the invention, the anvil drum is arranged in the transport direction of the material web, a baffle for taking over the material web or the front cut edge area of a sheet. The radial distance and / or the distance in the circumferential direction of the drum between the baffle plate and the anvil drum is of crucial importance. If the guide plate is too far apart from the anvil drum, there is a risk that the sheet will run into the gap between the guide plate and the anvil drum. In such a case, the process must be stopped and the sheet must be transferred to the guide plate manually. If the distance between the guide plate and the anvil drum is too small, the guide plate and the rotating anvil drum can touch, which can lead to damage to both the guide plate and the anvil drum. This can have a particularly negative impact on the quality of the cut performed. The distance is particularly preferably in a range from 0.1 to 2 mm, but can also be larger or smaller. Basically, the further transport of a sheet is also possible without a baffle.

It is advantageous if the distance of the guide plate from the anvil drum is adjustable, for example by means of hydraulic, pneumatic and / or mechanical adjustment devices. In this way, the distance can be set specifically to the requirements of the process and depending on the material web to be processed.

Advantageously, the baffle can have a blunt or pointed edge with which the baffle is arranged to the anvil drum. A pointed edge of the guide plate can be advantageous in that the distance between the guide plate and the anvil drum can be kept particularly small, so that the leading edge of a sheet can effectively prevent the area between the anvil drum and the guide plate. The targeted alignment of the distance between the guide plate and the anvil drum can effectively prevent accidents. It is also possible to change the orientation of the guide plate relative to the anvil drum and thus to adapt it to the conditions of the cutting process.

The guide plate preferably has at least one recess or groove on the side facing the anvil drum, the lifter being carried out through the recess or groove when the anvil drum rotates. The front one The area of the material web lies on the lifter after the cut and is radially spaced from the anvil drum. The lifter ensures that the front area of the material web is lifted or handed over to the guide plate. When the anvil drum is rotated further, the lifter is passed through the cutout or groove of the guide plate, so that the front area of the material web lies on the guide plate at the latest when the lifter is completely guided through the cutout or groove of the guide plate. Has the Am drum on several lifters, so each lifter is preferably assigned a recess or groove through which the lifter is carried out when the Am drum rotates. This ensures that the front area of the material web is evenly lifted or transferred to the guide plate over its entire width.

In the method according to the invention, the material web is in contact with at least one hold-down of a knife drum of the cross-cutting device during the squeeze cut in the region of the front edge newly formed during the cut and is arched by the hold-down device in the direction of an anvil drum of the cross-cutting device. Particularly preferred is an embodiment in which the web of material during the crimp cut in the area in front of the newly formed leading edge in contact with at least one lifter of the drum is in contact and raised by the lifter in the direction of the knife current mel, with, more preferably, the Material web in the area between the lifter and the hold-down device is curved essentially S-shaped.

According to the invention, the material web during cross cutting in the region of the leading edge formed during the cutting can be arched by at least one lifter and at least one spaced-down hold-down device for stabilization in the cut. The lifter can lift the area of the front edge of the material web after the cross cut from the anvil drum, the front edge of the material web can be transferred to a guide plate provided with at least one recess or groove in order to prevent the material web from running along with the knife drum. The material web is thus stabilized before and during the cut. The method thus leads to an improved reproducibility of the cutting process and to an improved quality of the cutting edge. At the same time, the transfer of the front region of the material web to a guide plate arranged downstream of the cross-cutting device is made possible in a reliable manner. The previously described embodiments of the invention can be combined with one another as required, even if this is not expressly mentioned in detail. The disclosure content of the invention is not limited to the combinations of inventive features specified by the selected paragraph formatting.

Further features of the present invention result from the following description of a preferred exemplary embodiment of the invention with reference to the drawings and from the drawings themselves. All of the described and / or illustrated features form the subject matter of the present invention independently or in any combination Summary in the claims or their relationships.

Show in the drawing

Figure 1 is a schematic representation of a cross cutting device according to the invention in section.

Fig. 2 is a perspective view of the cutting area of the Querscheideein direction of Figure 1 in a schematic representation.

Fig. 3 is a schematic cross-sectional view of the cross-cutting device shown in Fig. 1 after the cut and

Fig. 4 is a perspective view of the anvil drum and a material-leading guide plate of the cross cutting device according to the invention from Fig. 1 in a schematic representation.

Fig. 1 shows a cross cutting device 1 for cutting or cross cutting egg ner running material web 2 in sheets 3. The material web 2 is conveyed into the cross cutting device 1 by means of a guide plate 4 to be guided. The material web 2 is guided by the feeding baffle 4 in a cutting area between a knife drum 5 and a corresponding below the Messertrom mel 5 arranged anvil drum 6. The material web 2 is cut into sheets 3 in the cutting area. Subsequently, the material web 2 or the sheet 3 is transported away from the cross cutting device 1 via a discharging guide plate 7 and fed to the further processing process. For cutting the material web 2, the knife drum 5 has at least one knife 8, which preferably extends over the entire length of the knife drum 5. A hold-down device 9 is arranged in front of the knife 8 in the transport direction 10 on the knife drum 5. The hold-down device 9 can preferably be arranged immediately in front of the knife 8 or further apart from the knife 8.

When a cut is made, the knife 8 and the anvil drum 6 are in contact with one another in a cutting line. On the anvil drum 6 to a lifter 1 1 is arranged. The lifter 11 is arranged in the transport direction 10 of the material web 2 in front of the cutting line and is spaced from it. As shown in FIG. 1, the lifter 11 is arranged in relation to the sectional position of the drums 5, 6 shown in FIG. 1 in the transport direction 10 of the material web 2 in front of the hold-down device 9 and spaced from the hold-down device 9. However, it is also possible that the hold-down device 9 and the lifter 11 in the sectional position of the drum 5, 6 overlap in regions in the transport direction 10.

The web of material 2 is pressed by the hold-down device 9 before and during the cut in the direction of the anvil drum 5. During the cutting process or thereafter, the material web 2 rests on the lifter 11 at least in some areas. The never derhalter 9 presses on the upper flat side of the material web 2 and presses the mate rialbahn 2 with the opposite flat side in the direction of the anvil drum 6, whereby, preferably, the material web 2 thereby bear against the anvil drum 6. The material web 2 can also be clamped or held between the hold-down devices 9 and the anvil drum 6. In the area of the cutting line, the material web 2 is in any case on the anvil drum 6. In the transport direction 10 in front of the knife, the material web 2 is preferably arched essentially S-shaped due to the interaction of hold-down device 9 and lifter 11. In this way, the material web 2 is fixed in a stable position during the cut, which has a positive influence on the cut quality.

In Fig. 2 it is shown that several hold-down device 9 and lifter 11 are arranged transversely to the transport direction 10 of the material web 2 or in the longitudinal direction of the drums 5, 6 one behind the other. Fig. 2 shows the knife drum 5 and the Am boss drum 6 in the sectional state. The knife drum 5 has a plurality of hold-down devices 9 which are uniformly spaced apart from one another. The anvil drum 6 has also a plurality of lifts 1 1, which are also evenly spaced apart. The hold-down device 9 and the lifter 11 are arranged transversely to the transport direction 10 alternately. The distance between two adjacent hold-down devices 9 preferably corresponds to at least the width of a lifter 11. Transversely to the transport direction 10, the hold-down devices 9 and the lifter 11 can be at a distance of at least 1 mm from one another, for example.

In the arrangement shown in Fig. 1 and Fig. 2, the hold-down 9 and the lifter 1 1 do not overlap with respect to the position in section in the direction of transport 10 and can for example have a distance of at least 1 mm from each other. However, it is also possible that the lifters 1 1 and 9 hold down based on the position in section in some areas. The material web 2 can be deformed in the area of the lift 11 and hold-down device 9 in the transport direction 10 and transversely thereto. In this way, a complex and particularly stable three-dimensional curvature of the material web 2 can be achieved in the cut, whereby the cut quality is significantly improved.

As shown in FIGS. 1 and 2, the hold-down devices 9 and the lifters 11 have a distance from one another in the circumferential direction of the drums 5, 6 and in relation to the position on average. The curvature of the material web 2 can be varied by varying the distance. In this way it is possible, depending on the application, to set a different deformation of the material web 2.

After the cut has been carried out, the material web 2 is transferred to a discharging guide plate 7. As can be seen from FIG. 3, there is a gap between the guide plate 7 and the anvil drum 6. In order to prevent the front region of the material web 2 from running along with the anvil drum 6, as a result of which the material web 2 could get into the gap between the guide plate 7 and the anvil drum 6, the material web 2 is raised radially by the lifter 11 after the cut. After the cut, the anvil drum 6 and the mass drum 5 continue to rotate such that the hold-down device 9 loses contact with the material web 2, as shown in FIG. 3. The hold-down device 9 then no longer presses against the upper flat side of the material web 2 and / or presses the material web 2 no longer in the direction of the anvil drum, as a result of which the material web 2 can straighten up again in the front region due to the lift 11. The area in front of the material web 2 is then spaced radially from the anvil drum 6. In this way, the front area of the material web 2 can be leading baffle 7 are transferred or passed, whereby running of the material web 2 with the anvil drum 6 is prevented in an efficient manner. The material web 2 can no longer unintentionally run into the gap between the guide plate 7 and the anvil drum 6.

The cross cutting device 1 shown in FIG. 3 shows a second possible arrangement of the hold-down devices 9. In the transport direction 10 of the material web 2, the knife drum 5 has both a hold-down device 9 in front of the knife 8 and a hold-down device 9 behind the knife 8. During the cutting process, the material web 2 is stabilized by the two hold-down devices 9 on both sides of the knife 8, so that the cut quality can be further increased.

The lifter 11 of the anvil drum 6 can, as can be seen in FIG. 4, have an extension over a large part of the circumference of the anvil drum 6. The anvil drum shown in Fig. 4 can be easily manufactured by means of a milling process. The lifters 11 are formed by milling circumferential grooves. The lifters only have to be in a cutting area in which the cut and the pressing down of the material web 2 takes place through the holding-down devices 9

1 1 are removed in sections from the anvil drum. This can also be carried out by milling.

As can be seen in FIG. 4, the guide plate 7 has a plurality of cutouts

12 or grooves. Each recess 12 is assigned to a lifter 1 1, each lifter 1 1 being carried out in the drum rotation by a corresponding saving from the guide plate 7. In this way, a collision of the lifter 1 1 with the guide plate 7 is excluded. The lifter 1 1, the Ma material web 2 can thus safely pass to the baffle 7 and be carried out through the recesses 12. Thus, the lifters 1 1 not only have the function of interacting with the hold-downs 9 to stabilize the material web 2 on average, but also to transfer the material web 2 in a safe manner to the baffle plate 7. LIST OF REFERENCE NUMBERS

1 cross cutter 10 8 knives

2 material web 9 hold-down device 3 sheet 10 transport direction

4 baffle 1 1 lifter

5 knife drum 12 recess

6 anvil drum 15

7 baffle

Claims

claims:

1. Cross cutting device (1), in particular for cutting or cross cutting a running material web (2) preferably made of paper, cardboard, plastic and / or metal in sheets (3), with an axis of rotation running transversely to the material web (2) and its conveying direction rotatable knife drum (5) as a rotatable cutting device, the knife drum (5) having at least one knife (8) which extends in the axial direction of the knife drum (5) and has a corresponding knife (8) transverse to the knife drum (5) Materi albahn (2) and its axis of rotation extending axis of rotation on the anvil drum (6), the anvil drum (6) is preferably arranged vertically below the knife drum (5), with the contact of a knife (8) of the knife drum (5) with the An anvil drum (6) a squeeze cut is carried out in a cutting line, the knife drum (5) on its circumference we at least one hold-down device (9) in the transport direction (10) of the material web (2) in front of the knife (8), characterized in that the hold-down device (9) is at a distance from the knife (8) and / or has a radial extension such that the material web (2) during the crimp cut with the hold-down device (9) is in contact and is arched by the hold-down device (9) towards the anvil drum (6).

2. cross cutting device (1) according to claim 1, characterized in that the material web (2) is pressed during the crush cut by the hold-down device (9) against the Am bostrommel (6) and bears against the anvil drum (6).

3. cross cutting device (1) according to claim 1 or 2, characterized in that the anvil drum (6) at least one lifter (1 1) in the transport direction (10) of the material web (2) before the cutting line for stabilizing the material web (2nd ) during the cutting process.

4. cross cutting device (1) according to claim 3, that the lifter (1 1) in the movement regime of the cooperating knife drum (5) and anvil drum (6) in the transport direction (10) of the material web (2) at least substantially in front of the hold-down device (9) is arranged.

5. cross cutting device (1) according to claim 3 or 4, characterized in that transverse to the material web (2) and its conveying direction a plurality of spaced apart lifters (1 1) and / or spaced down holders (9) is provided.

6. cross cutting device (1) according to any one of the preceding claims, characterized in that the knife drum (5) on its circumference has at least one hold-down device (9) in the transport direction (10) of the material web (2) after the knife (8).

7. cross cutting device (1) according to one of claims 3 to 6, characterized in that the hold-down device (9) and the lifter (1 1) are arranged at least in the edge areas in a crimped cut intermeshing.

8. Cross cutting device (1) according to one of claims 3 to 7, characterized in that the lifter (1 1) and / or the hold-down device (9) consist of an elastic material, for example of a foam, a rubber material, or an elastomer material.

9. cross cutting device (1) according to any one of the preceding claims, characterized in that the anvil drum (6) in the transport direction (10) of the materi albahn (2) is arranged at least one guide plate (7) for taking over the cut sheet (3), wherein , Preferably, the guide plate (7) on the side facing the boss drum (6) has at least one recess or groove and the lifter (11) is carried out when the anvil drum (6) rotates through the recess or groove.

10. A method for stabilizing a cut edge in a crimp cut in a cross cutting device (1), in particular with a cross cutting device (1) according to one of the preceding claims, characterized in that the mate rialbahn (2) during the crimp cut in the region of the newly formed th leading edge during the cut is in contact with at least one hold-down device (9) of a knife drum (5) of the cross-cutting device (1) and is arched by the hold-down device (9) towards an anvil drum (6) of the cross-cutting device (1).

1 1. The method according to claim 10, characterized in that the material web (2) in contact with at least one lifter (1 1) of the anvil drum (6) during the squeeze cut in the area in front of the front edge newly formed during the cut stands and is raised by the lifter (1 1) in the direction of the knife drum (5), whereby, preferably, the material web (2) in the area between the lifter (1 1) and the hold-down device (9) is curved essentially in an S-shape ,