EP3645226B1 - Cross-cutting device and method for stabilizing a cutting edge during crush cutting - Google Patents

Description

The invention relates to a cross-cutting device, in particular for cutting or separating a running web of material preferably made of paper, cardboard, plastic and/or metal into sheets, with a cutter drum, which can be rotated about an axis of rotation running transversely to the web of material and its conveying direction, as a rotatable cutting device, the cutter drum being at least has a blade that rotates with the blade drum and extends in the axial direction of the blade drum, with a corresponding anvil drum that can be rotated about an axis of rotation running transversely to the material web and its conveying direction, the anvil drum preferably being arranged vertically below the blade drum, wherein when a blade comes into contact with the blade drum the anvil drum, a crush cut is carried out in a cutting line, the cutter drum having at least one hold-down device on its circumference in front of the cutter in the transport direction of the material web. In addition, the invention relates to a method for stabilizing a cut edge during a crush cut in a cross-cutting device.

From the document JP S50 95883 a transverse cutting device consisting of a knife drum on the one hand and an anvil drum on the other hand is known. The knife drum is a hold-down device and the anvil drum is assigned a lifter, with the hold-down device being arranged on the knife drum in front of the knife in the transport direction. In the cutting situation, the hold-down device and the lifter meet in alignment.

The document DE 20 2015 105 416 U1 relates to a rotating cutting and/or perforating device for web-like endless material. The device has two rollers which rotate about parallel axes of rotation and are closely spaced from one another, with a rotating cutting roller, a cutting blade and a counter-cutting roller being provided. A deflector element assigned to the cutting blade is also provided, which in the relaxed and/or expanded state protrudes beyond a blade of the cutting blade in the radial direction of the cutting roller.

The document CN 202 367 791 U relates to a cutting device consisting of a knife drum and a counter roller. The knife drum is equipped with a blade and provided with a depressing plate arranged in front of the blade in the cutting direction.

The document U.S. 5,918,518 discloses an apparatus for cutting a web with a cutterhead having a knife and a depressor associated with the knife. This depressor cooperates with an anvil roller.

The document CN 203993989 U relates to a cutterhead equipped with knives along its circumference. A press-down bar is assigned to each knife in the forward direction.

The document CN 103419230A discloses a cutting device with two drums arranged next to one another and with a knife drum arranged opposite thereto.

Finally, the document reveals JP2004142052 a cutting device with a knife drum and a counter-drum. The knife drum is equipped with a knife and in the cutting situation interacts with a strip-shaped counter surface of the anvil drum.

Cross-cutting devices consisting of a knife drum and a corresponding anvil drum, which perform a crush cut, are known from the prior art. The running web of material is cut crosswise 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 slide past the anvil essentially without play. In the direction of transport of the sheets, the cross cutter is usually followed by a guide plate, which is used to receive and further transport the sheets. The baffle plate is usually arranged downstream of the anvil drum, with the formation of a small gap. A gap remaining between the baffle plate and the anvil drum cannot be avoided due to the design, since touching contact between the anvil drum and the baffle plate can lead to damage to the baffle plate and/or the anvil drum.

The cut edge of the material web or a cut sheet often sticks 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 disrupted. The leading edge of the material web can run into the gap between the anvil drum and the guide plate, for example. The sheet in question is then not fed into further processing, which can lead to operational disruptions. However, it can also happen that the front cut edge of the material web sticks to the knife of the knife drum and runs along with the knife drum. This undesired behavior of the material web or the sheet can also lead to disruptions that can result in the cross-cutting device stopping and the sheet position being corrected manually.

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

The above object is achieved by a cross cutter having the features of claims 1 and 3 and by a method having the features of claim 8. The dependent claims reflect advantageous refinements of the invention.

Tests carried out within the scope of the invention have shown that the cutting quality of the cross-cutting device is highly dependent on the position of the material web relative to the knife and the anvil drum. According to the invention, the hold-down device of the cross-cutting device is therefore at a distance from the knife and/or a length or a radial extension in the direction of the anvil drum (relative to the position of the hold-down device during the crush cut) such that the material web is in contact with the hold-down device during the crush cut and is arched by the hold-down towards the anvil drum. The hold-down device is arranged on the circumference of the knife drum in front of the knife in the transport direction of the material web. The web of material is fed to the cross-cutting device via a guide plate and cut into sheets. The web of material is pushed down towards the anvil drum just before and during the cut. After the cut has been made, the hold-down device continues to press the front area of the material web downwards in the direction of the anvil drum. On the one hand, this prevents the front edge from running along with the cutterhead. On the other hand, the material web is arched in the direction of the anvil drum and is thereby stabilized in its position during cutting, resulting 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 cutting 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 cutterhead may have a single blade, which preferably extends substantially the entire length of the cutterhead. Such a cutterhead performs a cut for each complete revolution. Alternatively, a knife drum can also have several knives that extend over the entire length of the knife drum. A number of cuts corresponding to the number of knives is then carried out per rotation of the knife drum. In the last-mentioned case, the corresponding cross-cutting device also has a plurality of cutting lines and thus in any case also a plurality of hold-down devices. It is also possible for a blade that extends over the entire length of the drum to be subdivided into a number of blade sections or blade segments. The knife segments can then be exchanged independently of one another and/or adjusted to the width of the material web.

Advantageously, the material web is pressed against the anvil drum by the hold-down device during the crush cut and is already in direct contact with the anvil drum before the crush cut. The hold-down device acts against one, preferably upper, flat side of the material web and presses the material web against the anvil drum with the other flat side. The material web is thus clamped between the hold-down device and the anvil drum and guided during the cut with the movement of the two drums. The resulting bulge in the material web and the clamping of the sheet between the anvil drum and hold-down devices 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 produced, as a result of which the quality of the cut is improved.

The anvil drum has at least one lifter in the transport direction of the material web in front of 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 in an S-shape in the direction of the anvil drum. The material web preferably rests on the anvil drum in the area of the hold-down device and the cutting line during the cut. The S-shaped curvature significantly improves the stabilization of the material web, which has a positive effect on the cutting quality and the reproducibility of the cut. This has been confirmed by extensive tests carried out within the scope of the invention.

The lifter also has the function of preventing the leading edge or the front area of the material web from running along with the anvil drum. If the two drums continue to rotate after the material web has been cut, 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 radially lifted by the lifter and then no longer rests on the anvil drum in the area of the front edge. The curvature of the web of material decreases during this process until the web of material is no longer or only slightly arched. The cutting edge itself then rests neither on the lifter nor on the anvil drum. In this way, the leading edge area of the material web can be effectively prevented from running along with the anvil drum.

In the movement regime of the interacting knife drum and anvil drum, the lifter is arranged at least essentially in front of the hold-down device in the transport direction of the material web. The movement regime of the interacting knife and anvil drum describes the coordinated rotational movement of the knife drum and the anvil drum and the resulting interaction of the lifter and the hold down. The lifter and the hold-down device preferably act simultaneously against different flat sides of the material web during the crush cut. The lifter is spaced apart from the hold-down device in the circumferential direction of the drum. This means that the lifter is at a greater distance from the cutting line in the transport direction of the material web or in the circumferential direction of the drums 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 web of material in such a way that it rests on the hold-down device at least in some areas and is curved by the interaction of the hold-down device and the lifter. In the area of the cutting line, the material web preferably rests on the anvil drum during cutting. The curvature of the material web in the section can be influenced by the selection of the distance in the circumferential direction between the lifter and the hold-down device. The distance between the lifter and the hold-down is at least 2 mm.

In an alternative embodiment, a plurality of spaced-apart lifters and/or spaced-apart hold-down devices is provided transversely to the material web and its transport direction. The spaced-apart lifters segment a lift area, and spaced-apart hold-down devices segment a hold-down area. A uniform curvature of the web of material can be produced over the entire width of the web of material by the plurality of lifters and/or hold-down devices spaced apart from one another. This contributes in particular to increased stabilization of the material web in the cut and to improved cutting quality. The lifter and hold-down device are offset from one another in the transport direction of the material web. As a result, the curvature can take place in a manner that is gentle on the material. The cutter drum preferably has at least one hold-down device on its circumference after the cutter in the direction of transport of the material web. By arranging an additional hold-down device after the knife in the transport direction, the material web is pressed in the cut 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 cutting quality can be further improved.

The hold-down device and the lifter can be arranged such that they mesh with one another, at least in edge regions in the crush 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. If the hold-down device and lifter overlap or mesh at least temporarily and in edge areas during the cutting process, an advantageous bending or curvature of the material web in the transport direction and also a curvature of the material web transverse to the transport direction are achieved. If a plurality of spaced-apart lifters and hold-down devices is provided transversely to the material web, a wavy curvature of the material web can be produced transversely to the transport direction. Curvatures of the web of material created in the transport direction and transversely thereto are superimposed and form a complex, three-dimensional curvature in the web of material. 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 a foam material, a rubber material or an elastomer material. The throughput 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. It is thus possible to 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 comprise a rigid material. For example, the lifter may be milled into the anvil, in which case the lifter is made of the same material as the anvil. The lifters and hold-down devices are therefore suitable for a large number of possible material web properties to be processed.

The lifter and the hold-down device can each be designed as a separate element and can be arranged and fastened in an exchangeable manner on the knife drum or the anvil drum. The lifter and the hold-down device can be easily connected to the anvil or knife drum by screwing or clamping connected and thus easily changed and/or exchanged. In this way, 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 can also be non-removably connected to the drum. The lifter and the hold-down device can, for example, be connected in one piece 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 designed to be adjustable in height. Height-adjustable in this context 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, for example, take place hydraulically or mechanically, for example via adjusting screws. Appropriate devices and methods for radially adjusting an element are known to those skilled in the art.

A plurality of hold-down devices are preferably provided transversely to the transport direction, with the total extension of the hold-down devices in the longitudinal direction of the cutterhead, i.e. the sum of the individual lengths, being at least 5% of the length of the cutterhead, preferably at least 10%, preferably 15% to 45%. The hold-down devices are preferably evenly spaced apart from one another in the longitudinal direction of the cutterhead. By appropriately arranging the hold-down devices, a uniform curvature is produced in the material web over the width of the material web. The material web is also fixed evenly during the cut, so that the quality of the cut is consistently high along the cut.

Advantageously, several lifters are provided, the added extension of the lifters in the longitudinal direction of the anvil drum, ie the sum of the individual lengths, being at least 2%, preferably at least 5% of the length of the anvil drum, preferably at least 10%, preferably 15% to 45%. is equivalent to. Preferably, the lifters are evenly spaced longitudinally of the anvil drum. The alignment of the lifters leads to an even curvature of the material web and thus to an even fixation of the material web in the cut. At the same time it is ensured that the front area of the material web is radially lifted after the cut and prevented from running along with the anvil drum.

If several lifters and several hold-down devices are provided, the 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, a guide plate for taking over the material web or the front cut edge region of a sheet is arranged downstream of the anvil drum in the transport direction of the material web. The radial distance and/or the distance in the circumferential direction of the drum between the guide plate and the anvil drum is of decisive importance. If the distance between the guide plate and the anvil drum is too great, there is a risk that the sheet will enter the gap between the guide plate and the anvil drum. In such a case, the process must be stopped and the sheet manually transferred to the guide plate. If the distance between the baffle and the anvil drum is too small, the baffle and the rotating anvil drum may touch, which can result in damage to both the baffle and the anvil drum. As a result, in particular the quality of the cut that is carried out can be negatively influenced. The distance is particularly preferably in a range from 0.1 to 2 mm, but can also be larger or smaller. In principle, the further transport of a sheet is also possible without a guide plate.

It is advantageous if the distance between the guide plate and the anvil drum can be adjusted, for example by means of hydraulic, pneumatic and/or mechanical adjustment devices. In this way, the distance can be adjusted specifically to the requirements of the process and as a function of the material web to be processed.

The guide plate can advantageously have a blunt or pointed edge, with which the guide plate is arranged in relation 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 be effectively prevented from running into the area between the anvil drum and the guide plate. through the Targeted adjustment of the distance between the guide plate and anvil drum, accidents can be effectively avoided. It is also possible to change the alignment of the guide plate relative to the anvil drum and thus adapt it to the circumstances 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 guided through the recess or groove when the anvil drum rotates. The leading portion of the web rests on the lifter after the cut and is spaced radially from the anvil drum. The lifter ensures that the front area of the material web is lifted or transferred to the guide plate. As the anvil drum continues to rotate, the lifter is passed through the recess or groove of the guide plate, so that the front area of the material web rests on the guide plate at the latest when the lifter has passed completely through the recess or groove of the guide plate. If the anvil drum has a plurality of lifters, each lifter is preferably assigned a recess or groove through which the lifter is passed when the anvil drum rotates. This ensures that the front area of the material web is lifted or transferred to the guide plate evenly over its entire width.

In the method according to the invention, the material web is in contact during the crush cut in the area of the front edge newly formed during the cut with at least one hold-down device of a knife drum of the cross-cutting device and is curved 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 material web is in contact with at least one lifter of the anvil drum in the area in front of the front edge newly formed during the cut during the crush cut and is lifted by the lifter in the direction of the knife drum, with the material web being more preferably Area between the lifter and the hold-down device is essentially S-shaped.

According to the invention, the material web can be curved during cross cutting in the area of the front edge formed during the cut by at least one lifter and at least one spaced hold-down device for stabilization in the cut. The lifter can cut the leading edge area of the web after cross cutting lift from the anvil drum, whereby 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 improved reproducibility of the cutting process and improved quality of the cut edge. At the same time, the transfer of the front area of the material web to a guide plate arranged downstream of the cross-cutting device is made possible in a reliable manner.

Fig. 1

eine schematische Darstellung einer erfindungsgemäßen Querschneideeinrichtung im Schnitt;

Fig. 2

eine perspektivische Ansicht des Schneidbereichs der Querschneideeinrichtung aus Fig. 1 in einer schematischen Darstellung;

Fig. 3

eine schematische Querschnittsansicht der in Fig. 1 gezeigten Querschneideeinrichtung nach der Schnittdurchführung und

Fig. 4

eine perspektivische Ansicht der Ambosstrommel und eines materialabführenden Leitblechs der erfindungsgemäßen Querschneideeinrichtung aus Fig. 1 in einer schematischen Darstellung.

Show in the drawing

1

a schematic representation of a cross-cutting device according to the invention in section;

2

a perspective view of the cutting area of the cross cutter 1 in a schematic representation;

3

a schematic cross-sectional view of FIG 1 cross-cutting device shown after performing the cut and

4

shows a perspective view of the anvil drum and a material-removing guide plate of the cross-cutting device according to the invention 1 in a schematic representation.

1 shows a cross-cutting device 1 for cutting or separating a running material web 2 into sheets 3. The material web 2 is conveyed into the cross-cutting device 1 by means of a feeding guide plate 4. The material web 2 is guided by the feeding guide plate 4 into a cutting area between a cutterhead 5 and a corresponding anvil drum 6 arranged below the cutterhead 5 . The material web 2 is cut into sheets 3 in the cutting area. The material web 2 or the sheet 3 is then transported away from the cross-cutting device 1 via a discharging guide plate 7 and fed to further processing.

For cutting the material web 2 , the cutterhead 5 has at least one cutter 8 that preferably extends over the entire length of the cutterhead 5 . A hold-down device 9 is arranged on the knife drum 5 in front of the knife 8 in the transport direction 10 . The hold-down device 9 can preferably be arranged directly in front of the knife 8 or also at a distance 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. An elevator 11 is arranged on the anvil drum 6 . The lifter 11 is arranged in the transport direction 10 of the material web 2 in front of the cutting line and at a distance from it. As in 1 shown, the lifter 11 is referred to in 1 shown cutting position of the drums 5, 6 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 for the hold-down device 9 and the lifter 11 to overlap in areas in the cutting position of the drums 5, 6 in the transport direction 10.

The material web 2 is pressed by the hold-down device 9 in the direction of the anvil drum 5 before and during the cut. During the cutting process or afterwards, the material web 2 rests on the lifter 11 at least in certain areas. The hold-down device 9 presses on the upper flat side of the material web 2 and presses the material web 2 with the opposite flat side in the direction of the anvil drum 6 , the material web 2 preferably resting against the anvil drum 6 as a result. The web of material 2 can also be clamped or held in place between the hold-down devices 9 and the anvil drum 6 . In the area of the cutting line the material web 2 lies on the anvil drum 6 in any case. In the transport direction 10 in front of the knife, the material web 2 is curved, preferably in an essentially S-shape, due to the interaction of the hold-down device 9 and the lifter 11 . In this way, the material web 2 is fixed in a stable position during the cut, which has a positive effect on the quality of the cut.

In 2 shows that several hold-down devices 9 and lifters 11 are arranged one behind the other transversely to the transport direction 10 of the material web 2 or in the longitudinal direction of the drums 5, 6. 2 shows the knife drum 5 and the anvil drum 6 in the cutting state. The cutterhead 5 has a plurality of hold-down devices 9 spaced evenly apart from one another. The anvil drum 6 also has a plurality of lifters 11 which are also equally spaced from one another. The hold-down devices 9 and the lifters 11 are arranged in alternation transversely to the direction of transport 10 . 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 lifters 11 can have a distance of at least 1 mm from one another, for example.

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

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

After the cut has been made, the web of material 2 is transferred to a guiding plate 7 that is carried away. How out 3 can be seen is a gap between the Guide plate 7 and the anvil drum 6 available. In order to prevent the front area 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 radially lifted by the lifter 11 after the cut. After the cut, the anvil drum 6 and the mass drum 5 continue to rotate in such a way that the hold-down device 9 loses contact with the material web 2, as in 3 is shown. The hold-down device 9 then no longer presses against the upper flat side of the material web 2 and/or no longer presses the material web 2 in the direction of the anvil drum, as a result of which the material web 2 can straighten up again in the front area due to the lifter 11 . The front area 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 transferred or handed over to the discharging guide plate 7, with the material web 2 being prevented from running along with the anvil drum 6 in an efficient manner. The web of material 2 can no longer accidentally run into the gap between the guide plate 7 and the anvil drum 6 .

In the 3 The transverse cutting device 1 shown shows a second possible arrangement of the hold-down device 9 . During the cutting process, the material web 2 is stabilized by the two hold-down devices 9 on both sides of the blade 8, so that the cutting quality can be additionally increased.

The lifters 11 of the anvil drum 6 can be used as in 4 as can be seen, have an extension over a large part of the circumference of the anvil drum 6. In the 4 The anvil drum shown can be manufactured in a simple manner by means of a milling process. The lifters 11 are formed by milling peripheral grooves. The lifters 11 only have to be removed from the anvil drum in sections in a cutting area in which the cut and the pressing down of the material web 2 takes place by the hold-down devices 9 . This removal can also be done by milling.

As in 4 As can be seen, the baffle plate 7 has a plurality of recesses 12 or grooves. Each recess 12 is associated with a lifter 11, with each lifter 11 moving through a corresponding recess as the drum rotates of the guide plate 7 is carried out. In this way, a collision of the lifter 11 with the guide plate 7 is excluded. The lifters 11 can thus transfer the web of material 2 to the guide plate 7 in a safe manner and pass it through the recesses 12 . Thus, the lifters 11 not only have the function of stabilizing the material web 2 in the section in interaction with the hold-down devices 9, but also of transferring the material web 2 to the discharging guide plate 7 in a safe manner.

Reference list:

1

cross cutting device

2

web of material

3

arc

4

baffle

5

knife drum

6

anvil drum

7

baffle

8th

knife

9

hold-down

10

transport direction

11

lifter

12

recess

Claims (9)

1. Transverse cutting device (1), in particular for cutting or transversely severing a moving material web (2) of preferably paper, cardboard, plastic and/or metal into sheets (3), with a knife drum (5) rotatable about an axis of rotation extending transversely to the material web (2) and its conveying direction as a rotatable cutting device, the knife drum (5) having at least one knife (8) extending in the axial direction of the knife drum (5) and rotating with the knife drum (5), with a corresponding anvil drum (6) rotatable about an axis of rotation extending transversely to the material web (2) and its conveying direction, wherein the anvil drum (6) is preferably arranged vertically below the knife drum (5), wherein on contact of a knife (8) of the knife drum (5) with the anvil drum (6) a crush cut is made in a cutting line, wherein the knife drum (5) has on its periphery at least one hold-down device (9) in the transport direction (10) of the material web (2) in front of the knife (8), the hold-down device (9) having a distance from the blade (8) and/or a radial extent such that the material web (2) is in contact with the hold-down device (9) during the crush cut and is curved by the hold-down device (9) in the direction of the anvil drum (6), and the anvil drum (6) having at least one lifter (11) in the transport direction (10) of the material web (2) upstream of the cutting line for stabilizing the material web (2) during the cutting operation, characterized in that the lifter (11) is arranged at least substantially in front of the hold-down device (9) in the movement regime of the cooperating knife drum (5) and anvil drum (6) in the transport direction (10) of the material web (2), the lifter (11) being spaced further from the cutting line than the hold-down device (9) in the section in the transport direction of the material web (2), and the distance between the lifter (11) and the hold-down device (9) being at least 2 mm.
2. Cross-cutting device (1) according to claim 1, characterized in that the material web (2) is pressed against the anvil drum (6) by the hold-down device (9) during the crush cut and rests against the anvil drum (6).
3. A transverse cutting device (1), in particular according to claim 1 or 2, for cutting or transversely severing a moving material web (2) of preferably paper, cardboard, plastic and/or metal into sheets (3), with a knife drum (5) rotatable about an axis of rotation extending transversely to the material web (2) and its conveying direction as a rotatable cutting device, wherein the knife drum (5) has at least one knife (8) extending in the axial direction of the knife drum (5) and rotating with the knife drum (5), with a corresponding anvil drum (6) rotatable about an axis of rotation extending transversely to the material web (2) and its conveying direction, wherein the anvil drum (6) is preferably arranged vertically below the knife drum (5), wherein on contact of a knife (8) of the knife drum (5) with the anvil drum (6) a crush cut is made in a cutting line the knife drum (5) having on its circumference at least one hold-down device (9) in the transport direction (10) of the material web (2) in front of the knife (8), the hold-down device (9) being at a distance from the knife (8) and/or having a radial extent in such a way that the material web (2) is in contact with the hold-down device (9) during the squeezing cut and is curved by the hold-down device (9) in the direction of the anvil drum (6), and wherein the anvil drum (6) has at least one lifter (11) in the transport direction (10) of the material web (2) in front of the cutting line for stabilizing the material web (2) during the cutting operation, characterized in that the lifter (11) is arranged 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), a plurality of lifters (11) spaced apart from one another and/or hold-down devices (9) spaced apart from one another being provided transversely to the material web (2) and its transport direction.
4. Cross-cutting device (1) according to one of the preceding claims, characterized in that the knife drum (5) has on its circumference at least one hold-down device (9) in the transport direction (10) of the material web (2) after the knife (8).
5. Cross-cutting device (1) according to one of the previous claims, characterized in that the hold-down device (9) and the lifting device (11) are arranged to mesh with one another at least in edge regions in the crush cut.
6. Transverse cutting device (1) according to any one of the preceding claims, characterized in that the lifter (11) and/or the hold-down device (9) are made of an elastic material, for example a foam material, a rubber material, or an elastomer material.
7. Cross-cutting device (1) according to one of the previous claims, characterized in that at least one guide plate (7) is arranged downstream of the anvil drum (6) in the transport direction (10) of the material web (2) for taking over the cut sheet (3), the guide plate (7) preferably having at least one recess or groove on the side facing the anvil drum (6), and the lifter (11) being guided through the recess or groove during the rotation of the anvil drum (6).
8. Method for stabilizing a cut edge during a crush cut in a cross-cutting device (1) with a cross-cutting device (1) according to one of the preceding claims, characterized in that the material web (2) is in contact with at least one hold-down device (9) of a blade drum (5) of the cross-cutting device (1) during the crush cut in the region of the front edge newly formed during the cut and is curved by the hold-down device (9) in the direction of an anvil drum (6) of the cross-cutting device (1).
9. Method according to claim 8, characterized in that the material web (2) is in contact with the lifter (11) of the anvil drum (6) during the crush cut in the region in front of the leading edge newly formed during the cut and is lifted by the lifter (11) in the direction of the knife drum (5), wherein, preferably, the material web (2) is curved in an essentially S-shaped manner in the region between the lifter (11) and the hold-down (9).

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