DE20306776U1 - Transverse cutting of adjacent continuous metal or plastic sheet strips involves using a programmable cutting head moving along a cross rail - Google Patents

Abstract

Sheet material is unwound from stacked rolls (31') by a selector unit (32), which automatically feeds the selected material to an alignment (33) and width adjustment (4) unit. The material is slit longitudinally (5) into strips and sent to the transverse cutting unit (6). This has a cutting head that travels along a transverse rail and is positioned and moved according to a program to produce the required parts. Independent claims are also included for the following: (1) A programmable transverse cutting head with a driven upper rotary shear roller and a smaller lower idler roller, the cutting plane being in a slightly raised position. A pneumatically, hydraulically or electrically driven piston lifts the appropriate strip to the cutting position to facilitate cutting adjacent strips to different sizes; (2) An alternative programmable cutting head incorporating a linear shear or punch moving in a direction perpendicular to the sheet. The shear blade is opposed by lower blade running the full width of the machine.

Description

Erwin Reinisch
in Graz (AT)

Franz KRASER
in Schwanberg (AT)

Device for cross-cutting sheet metal or plastic sheets

The invention relates to a device according to the preamble of claim 1. Devices for cross-cutting material webs, in particular sheet metal webs, are known. With such devices it is possible to cut a delivered material web to length transversely to its transport direction. Such cross-cuts are currently essentially only carried out over the entire width of the delivered material web.

The aim of the invention is to be able to make more complex cuts, in particular to enable fully automatic, program-controlled, efficient cutting of material webs. Above all, it should be possible to make the cutting length adjustable transversely to the transport direction of the material web in order to be able to make dividing cuts precisely and efficiently.

This aim is achieved by a device of the type mentioned at the outset with the features stated in the characterising part of the claim!

According to the invention, it is possible to make a cross-section over a certain length and, when a number of webs are fed in side by side, to cut a single web crosswise. The device according to the invention is compact and works precisely and quickly.

The ability to position the cutting unit in any position transverse to the transport direction of the material web is particularly advantageous, since a corresponding cross-section can be started from any position or a corresponding cut can be made in any position.

The device according to the invention automates a device for cross-cutting, which reduces the number of personnel needed to process multiple orders. The strips can be cut to the finished size without having to be cut to length for subsequent processing. Furthermore, the cuts can be made in such a way that the required formats can be cut in the shortest possible time with the least possible waste.

In a preferred embodiment of the invention, the features of claim 2 are provided. With such a roller shear, cuts can be made quickly and precisely. It is advantageous if the features of claim 3 are provided, since in such an embodiment the edge area of a web that is arranged in front of the web to be cut in the cutting direction can be lowered so that the roller

shears can be moved beyond the web to be cut without cutting or damaging the adjacent web.

In an alternative embodiment, the features of claim 4 can be implemented. With the provided pressure unit, the edge area of the web to be cut facing the cutting unit is raised to a level located between the cutting blades. The lifting of the web is continued across the width of the web until the cut is completed or the pressure unit is disengaged from the web.

The features of claim 6 are useful for easier detection of a single web with a roller shear. With the provided sliding or catching shoe, a web arranged upstream of the web to be cut can be lowered or pressed downwards in its edge area, or the web to be cut can be guided precisely between the cutting blades with the sliding shoe.

The features of claim 7 are advantageous for precise execution and exactness of the cut. „ .

The effect of the actuating unit or the pressing unit or the sliding shoe is supported by the features of claim 13. This embodiment is made possible by implementing the features of claim 12, which relates to an advantageous combination of the device according to the invention with a longitudinal cutting unit. If the supplied webs are each delivered inclined at a certain angle to the web plane, the sliding shoe can move better under a web.

In a preferred embodiment of the invention, the features of claim 9 are implemented. With such a shear-like cutting unit, cuts can be made at predetermined positions. The length of the cuts depends on the length of the shear blade and also on the extent of the cutting stroke. With a small stroke height of the work cycle, a short cut can be made, with a larger stroke, a longer cut, but a maximum of one cut corresponding to the length of the shear blade. It is advantageous in such an embodiment if the features of claim 10 are implemented, since such an embodiment can be constructed particularly simply and inexpensively.

In the following, the invention is explained in more detail with reference to the description, the drawings and the claims, in which advantageous embodiments of the invention are described.

Fig. 1 shows a schematic view of a material web processing unit, in particular an automatic multiple coil and cutting system for strip sheets. Fig. 2 shows a schematic view of a strip shear with roller knives. Fig. 3 shows a front view of the strip shear. Fig. 4 shows a device according to the invention or cross shear in front view or against the transport direction. Fig. 5 shows a cross shear in front view during

of cutting a sheet to length. Fig. 6 shows a side view according to Fig. 5. Fig. 7 shows schematically the cutting of a sheet metal sheet to length. Fig. 8 shows an embodiment of a cross shear in a front view against the transport direction. Fig. 9 shows an embodiment according to Fig. 8 in an oblique view. Fig. 10 shows an embodiment of a cross shear in a front view against the transport direction. Fig. 11 shows an embodiment according to Fig. 9 in a side view. Fig. 12 shows an embodiment according to Fig. 10 in an oblique view. Fig. 13 shows a detail of the cutting unit.

Fig. 1 shows a schematic overall view of a device for processing material webs, in particular sheet metal webs or plastic webs. 31 denotes unwinding devices or roll carriers. The material webs or starting webs are unwound from the respective rolls 31' and fed to a multiple feeder 32, which enables automatic switching between webs of different thicknesses, different widths, different materials, etc. From this multiple feeder 31, the selected web is guided through a straightening unit 33 and a device for automatic width adjustment 4. The sheet metal web is then fed to a slitting unit 5, which is followed by a device 6 according to the invention for cross-cutting the individual sheet metal webs. In the slitting unit 5, the supplied material web is divided into a predetermined number of individual webs that are fed next to one another using an appropriate number of roller knives 7, 8. The roller knives 7, 8, which can be adjusted across the width of the material web, cut the supplied material web longitudinally into individual webs of predetermined width. In the device 6 for cross-cutting, the individual webs 1, 2, 3 can be cut or cut to length independently of one another. The special design of the device 6 according to the invention makes it possible to cut the webs 1, 2, 3 coming from the longitudinal cutting unit 5 in different lengths according to the program of a cutting optimization software and controlled by a positioning or control unit (not shown). According to the invention, each of the webs can be cut at any desired point.

Fig. 2 shows a view of the longitudinal cutting unit 5. The longitudinal cutting unit 5 has a number of upper knives 7 and lower knives 8, which work together and form longitudinal cuts in the fed material web. The upper knives 7 and lower knives 8 are mounted on an upper driven knife shaft 9 and on a lower driven knife shaft 10, each displaceable in the longitudinal direction of the shaft and can be fixedly positioned for the cutting position. This allows webs 1, 2, 3 of different widths to be created and fed to the device 6 for cross-cutting.

Fig. 3 shows a front view of the longitudinal cutting unit 5. The upper and lower knives 7,8 carry cutting rings 11 and guide or support rings 12. Fig. 3 shows the upper knife shaft 9 in the raised position; for the cutting process, the upper knife shaft 9 is lowered. Due to the different height levels of the cutting knives 11 and the

Guide rings 12 give the sheet metal webs 1, 2, 3 leaving the interacting roller knives 7, 8 an inclination with respect to the web plane B. In the area on the left in Fig. 2 and 3, the height level of the side edge of a web is lower than in the right side edge area, since the height level there is determined by the higher circumference of the cutting knife 11. The device 6 according to the invention can make use of this inclination of the webs 1, 2, 3.... for cross-cutting.

The knife rollers 7, 8 are driven in opposite directions and convey the individual cut material webs in the direction of the device 6 according to the invention for cross-cutting. Fig. 3 shows a position of the upper knife shaft 9 and the lower knife shaft 10 in which no cutting process takes place; this could, for example, be the time at which a change of a material web to be cut takes place or a cross-section through a web takes place. While the device 6 according to the invention for cross-cutting is in operation, the material web is not transported further or the cross-cutting takes place while all webs are at a standstill.

It is particularly advantageous if the device 6 according to the invention is arranged immediately after the strip shears 5.

4 to 7 show an advantageous embodiment of a device 6 according to the invention. On a guide track 13 extending transversely or perpendicularly to the transport direction T of the material webs 1, 2, 3 to be cut transversely, a cutting unit 15 can be adjusted or displaced transversely to the webs 1, 2, 3 and positioned as desired by means of a drive 14. A base body or carriage 16 of the cutting unit 15 carries a knife carrier or a knife plate 17 on which two interacting roller knives 18 and 19 are rotatably mounted. The lower roller knife 19 is covered or not visible in Fig. 4 by a sliding or guide shoe 20. The upper roller knife 18 and the lower roller knife 19 are arranged at the same height so that the sheet metal webs 1, 2, 3 come to lie at the level of the cutting area. The knife carrier 17 can be mounted on the base body 16 with an adjustment cylinder 22 so that it can be adjusted in height or pivoted in order to be able to adapt the roller knives 18, 19 to different web levels.

The upper roller knife 18 is driven by a knife drive 23; the lower roller knife 19 runs along with it. The cutting unit 15 is slidably mounted with the carriage 16 on the guide rails 26 of the guide track 13.

The base body or linear slide 16 carries an actuating unit comprising a pressure cylinder 24 for adjusting a pressure component that is adjustable in height or can be adjusted up and down or pivoted, preferably a pressure roller 25.

Fig. 4 shows the cutting of a material web that has been split lengthwise into three webs 1, 2, 3 across its entire width. The sheet metal webs 1, 2, 3 supplied by the slitting device 5, which run slightly inclined relative to the web plane B, are cut with

a cut of the cutting unit 15. In this way, an initial cut or an end cut or a desired continuous cut can be made to cut all the webs to length.

Fig. 5 to 7 show the cutting of a web 2 which is located between two neighboring webs 1 and 3. The cutting unit 15 is shown in Fig. 5 in a position in which the final phase of the cutting of the web 2 takes place. The cut begins after the right edge area of the web 1 has been pressed down with the guide shoe 20 or the lower roller knife 19 and the left edge of the web 2 comes to lie between the upper roller knife 18 and the lower roller knife 19 or has been inserted between these roller knives. The cutting unit S is then moved to the right in Fig. 5 in the cutting direction until the cut is completed. In order not to damage the left side edge of the web 3, the pressure roller 25 mounted on a roller carrier 27 is lowered due to a corresponding actuation of the pressure cylinder 24 and the edge of the web 3 is pressed downwards so that the web 3 is not damaged or cut.

Fig. 6 shows a side view of the device 6 according to Fig. 5. One can see the downwardly bent web 3, which is pressed downwards by the pressure part 25.

Fig. 7 shows a view of the device 6 according to the invention, in which the cutting unit 15 has finished cutting the web 2. The pressure roller 25 presses the web 3 downwards so that the guide shoe 20 comes to lie above the web 3 and thus the upper roller knife 18 and the lower roller knife 19 cannot cut the web 3 or the cutting unit 15 can be moved above the web 3.

Fig. 8 shows an embodiment of a device 6 according to the invention, in which the cutting unit 15 with the drive 14 can be moved and positioned on the guide track 13 transversely in the transport direction of the tracks 1, 2, 3. A lower slide 30, in particular coupled to the slide or base body 16 of the cutting unit 15, can be moved on a lower guide track 29 parallel to it, for which purpose a separate drive 34 can also be provided if necessary. The carriage 16 carries an upper roller knife 18 and a lower roller knife 19 as well as a guide shoe 20 on the knife carrier 17. A pressure part 25 is not provided. In order to enable the guide shoe 20 to penetrate beneath a web 2 to be cut to length or to raise the web 2 to the cutting level, the lower carriage 30 carries a pneumatically, hydraulically or electronically operated bending cylinder 45 which actuates or moves a pressure component 36 up and down. By raising the pressure component 46 accordingly, the web 2 can be raised to a level above the two adjacent webs 1 and 3, which level corresponds to the cutting level of the cutting unit 15. This avoids any impairment of the adjacent webs 1 or 3 when cutting the web 2. The roller knives 18, 19, in particular the lower roller knife 19 and the guide shoe 20, are mounted or movable so high above the transport level of the tracks 1, 2, 3 that the

the linear dividing device 5 or the strip cutter can be transported underneath the webs 1, 2, 3. During the cutting process, the web 2 to be cut is lifted shortly before the incoming cutting unit 15 and brought into the cutting area of the roller knives 18, 19. This allows individual sections or strips to be cut from the adjacent webs.

The two linear slides 16, 30 can be coupled mechanically, electronically or by drive.

Fig. 9 shows a web 2 raised by means of the pressure component 46, which is grasped and cut off by the cutting unit 15.

Advantageously, the upper blade 18 has a considerably larger diameter than the lower blade. The diameters are approximately 1:4 and 1:5, respectively.

The linear slides 16, 30 are driven by the control or positioning unit, advantageously by means of an incremental encoder, in order to be able to carry out exact positioning and cutting lengths.

Fig. 10 shows an embodiment of a device 6 according to the invention, in which the cutting unit 15 has at least one linear knife 35 which is actuated or moved up and down in cycles by a cutting cylinder 37. The cutting unit 15 can be adjusted or positioned along the guide track 13 on a linear slide 16 using a slide drive 14.

The linear knife 35, which has a cutting surface inclined to the plane of the webs 1, 2, 3, interacts with a cutting knife or cutting bar 36 running transversely to the webs 1, 2, 3. As can be seen from Fig. 10, it is advantageous to provide a continuous cutting bar 36 with which the punching knife 35 interacts. In this way, depending on the length of the punching knife 35, transversely to the transport direction T of the webs 1, 2 and 3 and depending on the stroke given to the linear knife 35 by a cutting cylinder 37, cuts with a length predetermined by the control unit can be made. The desired total cutting length is achieved by appropriate movement and, if necessary, multiple actuation of the cutting unit 15. Several punching knives can be arranged one after the other on the carriage 16 transversely to the transport direction T.

Fig. 11 shows a side view of the cutting unit 15. The upper knife 18 formed by at least one punching knife 35 cooperates with the lower knife formed by a cutting bar 36 for cross-cutting the web 2.

Fig. 12 shows a schematic representation of the cutting of a partial area of the web 2. After several cuts have been made, the web 2 is severed.

The cutting unit 15 according to Fig. 10 to 12 works according to the principle of a shear. The sheet metal strips 1, 2, 3 coming from the strip shear 5 are transported via the cutting bar 36. The upper blade 35 is kept relatively short in order to

narrow strips in one working stroke." The movement of the linear slide 16 transporting the cutting unit 15 takes place with the drive 14 by means of the control or positioning unit via an incremental encoder. The upper knife 35 is driven either pneumatically, hydraulically or electrically. To cut off a web, e.g. web 2, the upper knife 35 must perform a number of strokes, which are carried out in cycles after the linear slide 16 has been moved accordingly.

A sensor mounted on the knife plate or the knife carrier 17 or the carriage can be used to determine whether there is a path next to the cutting unit 15 or next to the roller knives 18 and 19 or the knife 35 and thus no empty cut is made.

To cut off the supplied webs across their entire width or to make a zero cut or to cut off all webs of the same length coming from a strip cutter 5, the cutting unit 15, which is initially in a basic position outside the transport area of the material webs, is activated. The pressure roller 25 and the knife carrier 17 are raised. The webs are positioned but the web feed drive is stopped, i.e. the material web or webs are not fed in the transport direction T. As a result, in the embodiment according to Figs. 1 to 7, the knife plate 17 with the roller knives 18 and 19 is lowered into the cutting position. The drive 23 for the upper roller knife 18 is switched on and the cutting unit 15 is transported via the linear slide 16 transversely to the transport direction T of the individual strips 1, 2, 3. After the roller knives 18 and 19 start cutting, the severed web part or the side area of the web sinks into the reporting or sensor area of the sensor, so that a correct cutting process is reported to the control unit.

If the cutting unit 15 has covered the path specified by the control unit or positioning unit, the corresponding web part is severed, which separation process is also confirmed by the sensor.

The cutting unit 15 is then moved to its home position or the cutting process is continued in the adjacent lane.

When cutting a web 2 that is arranged between two adjacent webs 1 or 3, the cutting unit 15 is positioned directly in front of the web 2 to be cut. The pressure roller 25 is raised. The belt feed drive is stopped or the individual webs are at rest. The knife carrier 17 with the roller knives 18 and 19 is lowered into the cutting position. The web 1 that is not to be cut is pressed downwards by the knife carrier 17 or the lower knife roller 19 or the guide shoe 20. The web 2, however, remains at its original height. This process is made easier by the web 2 coming from the strip cutter.

1, 2, 3 advantageously have a slight twist or inclination due to the different diameters of the cutting rings 11 and the support rings 12.

The drive 23 for the upper roller knife 18 is then switched on and the cutting unit 15 is pulled through the web 2 to be cut via the driven linear slide 16. Shortly after the roller knives 18, 19 have started to cut the web, the severed web area comes into the field of view of the sensor carried by the base body 16 or the knife carrier 17, so that a correct cutting process is reported.

The cross cutter or the cutting unit 15 is now positioned or moved further until the push-off roller 25 is above the edge area of the adjacent or next web 3. The push-off roller 25 is now lowered and the near edge area of the next web 3 is pressed downwards. The cutting unit 25 can therefore continue to move, since the web 3 pressed downwards cannot be grasped, but slides under the lower roller knife 19 or under the guide shoe 20.

After the cutting unit 15 has covered the path specified by the control unit, the web 2 is severed, which fact is also confirmed by the sensor. The knife carrier 17 or the guide shoe 20 and the lower roller knife 19 as well as the pressure roller 25 are then raised and the cutting unit 15 is returned to its basic position or adjusted to another, specified cutting position.

An advantage of the device 6 according to the invention is also that immediately after the knife carrier 17 or the guide shoe 20 or the lower roller knife 19 is raised, the webs 1, 2, 3 can be moved further again until at least one of the webs comes into the cutting position again, in which position the feed of the webs is stopped again.

Fig. 13 shows two views of an upper roller knife 18 and a lower roller knife 19 that interacts with it. The guide shoe is attached to the knife carrier 17. The knife carrier 17 can be pivoted about a pivot axis 50, about which the roller carrier 27, which carries the pressure roller 25, can also be pivoted. The lower roller knife 19 can be mounted on the guide shoe 20.

The embodiments of the invention characterized in claims 14 to 17 have proven in practice to be reliable and structurally simple devices for cross-cutting.

Claims (18)

1. Device for cross-cutting material webs, in particular sheet metal or plastic webs, with at least one cutting unit ( 15) movable transversely to the transport direction of the webs on a guide track (13 ) , characterized in that - that a number of material webs are fed to the device ( 6 ) lying next to one another, - that the cutting unit ( 15 ) is adjustable or movable and positionable on its guide track ( 13 ), in particular with a linear slide ( 16 ), with a positioning or control unit and - that the cutting unit ( 15 ) can be driven in a predetermined position or starting from a predetermined position to produce at least one cross-section of predetermined length or can be moved on the guide track ( 13 ). 2. Device according to claim 1, characterized in - that the cutting unit ( 15 ) designed as a roller shear comprises a driven upper blade ( 18 ) and a preferably rotating lower blade ( 19 ), which roller blades ( 18 , 19 ) are rotatably mounted on a blade carrier ( 17 ), the area between the upper blade ( 18 ) and the lower blade ( 19 ) comprising the plane of the webs ( 1 , 2 , 3 ), and - that, if necessary, the knife carrier ( 17 ) is mounted in a plane vertical to the track plane (B) so as to be height-adjustable or pivotable on a base body ( 16 ), preferably a linear slide, which can be moved on the guide track ( 13 ) under the control of the positioning or control device. 3. Device according to claim 2, characterized in that a pressure part ( 25 ), in particular a pressure roller, which is height-adjustable or height-pivotable with an actuating unit carried by the base body (16 ) , preferably a hydraulic or pneumatic or electric actuating cylinder ( 24 ), is arranged upstream of the upper knife (18) in the cutting direction, which can be lowered below the web plane or with which the edge region of the next web ( 3 ) located in front of the cutting unit ( 15 ) can be loaded or pressed downwards. 4. Device according to claim 1 or 2, characterized in that - that the upper blade ( 18 ) and the lower blade ( 19 ) are mounted or movable above the web plane (B) and - that a pressure unit (45, 46) which can be moved below the web plane (B) parallel to the cutting unit ( 15 ) and transversely to the transport direction (T) of the webs ( 1 , 2 , 3 ), in particular on a guide track ( 29 ) with a linear slide ( 30 ), preferably coupled to the cutting unit ( 15 ) , is provided for lifting an edge region of a web (1, 2, 3 ) which is located in front of the cutting unit ( 15 ) and faces this or is to be grasped by the cutting unit ( 15 ) for a cut. 5. Device according to claim 4, characterized in that the printing unit comprises a pneumatically, hydraulically or electrically actuated stamp ( 45 ) which carries a printing part ( 46 ) which can preferably be moved up and down vertically to the web plane (B). 6. Device according to one of claims 1 to 5, characterized in that the lowermost part or region of the roller shears or cutting unit ( 15 ) is formed by the lower roller knife ( 19 ) or by a sliding or catching shoe (20) which is pivotably mounted on the knife carrier ( 17 ) and/or the carrier of the lower knife ( 19 ), optionally in a plane (B) vertical to the web plane ( B ) and/or is movable up and down. 7. Device according to one of claims 1 to 6, characterized in that the diameter of the lower roller knife ( 19 ) is 10 to 30%, preferably 18 to 26%, of the upper roller knife ( 18 ). 8. Device according to one of claims 1 to 7, characterized in that a sensor is carried by the cutting unit ( 15 ) or by the base body ( 16 ) or by the knife carrier ( 17 ), which sensor detects the presence of a web ( 1 , 2 , 3 ) to be cut in the cutting area of the cutting unit ( 15 ). 9. Device according to one of claims 1 to 9, characterized in that the cutting unit ( 15 ) comprises at least one striking or punching knife ( 35 ) located above the web plane (B), which can be moved up or down in a plane running vertically to the web plane (B) and interacts with at least one counter knife ( 36 ), in particular a cutting bar, located below the web plane (B), optionally extending over the entire width of the webs ( 1 , 2 , 3 ), preferably having a horizontal cutting surface, and mounted in a vertically immovable manner. 10. Device according to claim 10, characterized in that - that the upper knife ( 35 ), which can be moved up and down by a drive ( 37 ), can be positioned and moved on a guide track ( 13 ) on a linear slide ( 16 ) transversely to the transport device (T) by the positioning or control unit. 11. Device according to claim 10 or 11, characterized in that the lifting height of the upper blade ( 35 ), which preferably has a cutting surface running obliquely or inclined to the web plane (B), is adjustable by the control unit. 12. Device according to one of claims 1 to 12, characterized in that the device ( 6 ) is arranged downstream of a longitudinal cutting unit ( 5 ), in particular strip shears, for material webs, from which the webs or strips ( 1 , 2 , 3 ) obtained from an initial web by longitudinal cutting are fed to the device ( 6 ) lying next to one another. 13. Device according to claim 12, characterized in that in particular each of the individual delivered webs ( 1 , 2 , 3 ) has an inclination transverse to the transport direction (T), wherein the inclination is formed by the cutting and support ring surfaces or rings ( 11 , 12 ) located at different height levels of cutting rollers ( 7 , 8 ) of roller shears of the longitudinal cutting unit ( 5 ) located next to one another or mounted on drive shafts ( 9 , 10 ) extending transversely to the transport direction of the webs ( 1 , 2 , 3 ). 14. Device for cross-cutting sheet metal or plastic webs, with at least one cutting unit ( 15 ) that can be moved transversely to the transport direction of the webs on a guide track ( 13 ), wherein a number of material webs are fed to the device ( 6 ) lying next to one another, wherein the cutting unit ( 15 ) can be adjusted or moved and positioned on its guide track ( 13 ), in particular with a linear slide ( 16 ), with a positioning or control unit, and wherein the cutting unit ( 15 ) can be driven in a predetermined position or starting from a predetermined position to carry out at least one cross-section of a predetermined length or can be moved on the guide track ( 13 ), in particular according to one of claims 1 to 13, characterized in that - that the cutting unit ( 15 ) designed as a roller shear comprises a driven upper blade ( 18 ) and a preferably rotating lower blade ( 19 ), which roller blades ( 18 , 19 ) are rotatably mounted on a blade carrier ( 17 ), wherein the area between the upper blade ( 18 ) and the lower blade ( 19 ) comprises the plane of the webs ( 1 , 2 , 3 ), or - that the upper blade ( 18 ) and the lower blade ( 19 ) are mounted or movable above the web plane (B), wherein a pressure unit (45, 46) movable below the web plane (B) parallel to the cutting unit ( 15 ) and transversely to the transport direction (T) of the webs ( 1 , 2 , 3 ), in particular on a guide track ( 29 ), with a linear slide ( 30 ) with the cutting unit ( 15 ), preferably coupled, is provided for lifting an edge region of a web ( 1 , 2 , 3 ) located in front of the cutting unit ( 15 ) and facing it or to be grasped by the cutting unit ( 15 ) for a cut, wherein optionally the pressure unit comprises a pneumatically, hydraulically or electrically actuated stamp ( 45 ) which can be raised and lowered preferably vertically to the web plane (B). movable pressure part ( 46 ). 15. Device according to claim 14, characterized in that the knife carrier ( 17 ) is mounted in a vertical plane to the track plane (B) so as to be height-adjustable or pivotable on a base body ( 16 ), preferably a linear slide, which can be moved on the guide track ( 13 ) under the control of the positioning or control device. 16. Device according to claim 14 or 15, characterized in that a pressure part ( 25 ), in particular a pressure roller, which is height-adjustable or height-pivotable with an actuating unit carried by the base body (16 ) , preferably a hydraulic or pneumatic or electric actuating cylinder ( 24 ), is arranged upstream of the upper knife (18) in the cutting direction, which can be lowered below the web plane or with which the edge region of the next web ( 3 ) located in front of the cutting unit ( 15 ) can be loaded or pressed downwards. 17. Device for cross-cutting sheet metal or plastic webs, with at least one cutting unit ( 15 ) that can be moved transversely to the transport direction of the webs on a guide track ( 13 ), wherein a number of material webs are fed to the device ( 6 ) lying next to one another, wherein the cutting unit ( 15 ) can be adjusted or moved and positioned on its guide track ( 13 ), in particular with a linear slide ( 16 ), with a positioning or control unit and wherein the cutting unit ( 15 ) can be driven in a predetermined position or starting from a predetermined position to carry out at least one cross-section of a predetermined length or can be moved on the guide track ( 13 ), in particular according to one of claims 1 to 16, characterized in that - that the cutting unit ( 15 ) comprises at least one striking or punching knife ( 35) located above the web plane (B), which can be moved up or down in a plane running vertically to the web plane (B) and interacts with at least one counter knife (36 ) , in particular a cutting bar, located below the web plane (B), optionally extending over the entire width of the webs ( 1 , 2 , 3 ), preferably having a horizontal cutting surface, and mounted in a vertically immovable manner, wherein optionally the upper knife (35) which can be moved up and down by a drive ( 37 ) can be positioned and moved on a guide track ( 13 ) on a linear slide ( 16 ) transversely to the transport device (T) by the positioning or control unit and/or the lifting height of the upper knife ( 35 ), which preferably has a cutting surface running obliquely or inclined to the web plane (B), 35 ) can be adjusted by the control unit.