Method for Regulating the Processing of a Material Web on the Basis of Register Marks, and Apparatus for Carrying Out the Method

Abstract

A method for regulating the processing of a material web that has register marks and is driven via at least one drive roller is described, in which the register marks are guided past at least one sensor that captures register marks and an evaluation device determines the deviation of an actual position, corresponding to the capturing event, of at least one processing tool from a predetermined position of the at least one processing tool, and in which a regulating device uses the deviation between the actual position and the predetermined position of the at least one processing tool to regulate the actual processing position of the at least one processing tool. The evaluation device determines the actual distance between successive register marks with regard to the measurement system of the at least one drive roller and correlates this with an expected distance between the register marks with regard to the measurement system of the at least one drive roller.

Claims

1. A method for regulating a processing of a material web having register marks which are guided past a processing device for the purpose of processing, the method comprising: driving the material web via at least one drive roller; guiding the material web past at least one sensor that captures the register marks: determining a deviation of an actual position with an evaluation device, corresponding to a capturing event of a register mark by the at least one sensor of at least one processing tool of the processing device from a predetermined position of the at least one processing tool for the capturing event; using the deviation with a regulating device between the actual position and the predetermined position of the at least one processing tool determined by the evaluation device of the at least one processing tool to regulate an actual processing position; using successive capturing events of register marks by the at least one sensor with the evaluation device to determine an actual distance of successive register marks in relation to a measurement system of the at least one drive roller, and correlating the actual distance with an expected distance of the register marks with regard to the measurement system of the at least one drive roller; determining a pilot-control value from the correlation between the actual distance and the expected distance of the register marks; and adjusting speed of the at least one processing tool as a function of the pilot-control value with a control device.

2. The method according to claim 1, wherein the evaluation device determines the pilot-control value as a function of the path velocity of the material web in a region of the at least one sensor in relation to the measurement system of the at least one drive roller.

3. The method according to claim 1, wherein the at least one processing tool is motorized.

4. The method according to claim 1, wherein the actual processing position of the at least one processing tool is regulated by a brief acceleration and/or deceleration of the speed of the processing tool.

5. The method according to claim 1, wherein the processing position of the at least one processing tool is regulated by a control loop through brief accelerations or brakings of the at least one processing tool moving with a predetermined speed, and/or wherein the predetermined speed of the at least one processing tool is increased or decreased via a pilot control.

6. The method according to claim 1, wherein as the at least one processing tool, a cutting tool, a perforation tool, an embossing tool, a folding tool, a stamping tool and/or a printing tool is used.

7. The method according to claim 1, wherein the material web comprises a packaging material web, a packaging material laminate, and/or a board/plastic packaging material laminate.

8. The method according to claim 1, wherein the register marks integrated into a decoration or provided alongside a decoration print marks, embossings, folds, stampings and/or material differences are used.

9. The method according to claim 1, wherein a release device or door control uses the capturing events of the register marks by the at least one sensor to specify a time-related and/or a distance-related window for a following expected capturing event, in which the capturing event of a register mark by the at least one sensor is captured, relayed and/or processed at the evaluation device-.

10. A device for the processing of a material web comprising: a processing device having at least one processing tool; at least one drive roller for driving the material web; at least one sensor for capturing register marks of the material web guided past the sensor; an evaluation device for determining a deviation of an actual position, corresponding to the capturing event of the register mark by the at least one sensor of the at least one processing tool of the processing device from the predetermined position of the at least one processing tool for the capturing event; a regulating device for regulating the actual processing position of the at least one processing tool using the deviation between the actual position and the predetermined position of the at least one processing tool determined by the evaluation device, wherein the evaluation device is configured to determine a pilot-control value as a function of the path velocity of the material web in an area of the at least one sensor using successive capturing events of register marks by the at least one sensor, wherein the pilot-control value is determined on the basis of the correlation between the actual distance of successive register marks in relation to the measurement system of the at least one drive roller, and an expected distance of the register marks in relation to the measurement system of the at least one drive roller; and a control device for adjusting the speed of the at least one processing tool as a function of the pilot-control value.

11. The device according to claim 10, wherein the at least one processing tool is motorized.

12. The device according to claim 10, wherein a roller sensor is provided for capturing a parameter dependent upon the measurement system of the at least one drive roller.

13. The device according to claim 10, wherein the processing tool is associated with a position sensor.

14. The device according to claim 10, wherein the at least one processing tool is a cutting tool, a perforation tool, an embossing tool, a stamping tool and/or a printing tool.

15. The method according to claim 3, wherein the at least one processing tool is rotated about an axis, parallel to the material web and perpendicular to the transport direction of the material web in each case in an area of the processing device.

16. The device according to claim 11, wherein the at least one processing tool rotates about an axis of rotation, parallel to the material web and perpendicular to the transport direction of the material web of the processing device.

17. The device according to claim 14, wherein the material web comprises a packing material web, a packaging material laminate, and/or a board/plastic packaging material laminate.

18. The device according to claim 17, wherein the register marks are print marks, embossings, perforations, foldings, punchings, or material differences integrated into a decoration or alongside a decoration.

19. The method according to claim 1, wherein the measurement system of the at least one drive roller comprises an angular difference of the drive roller and/or a circumferential difference of the drive roller.

20. The device according to claim 12, wherein the roller sensor is configured to capture an angular difference of the drive roller and/or a circumferential difference of the drive roller.

Description

[0046] FIG. 1 shows a device for the processing of a material web 2 in the form of a packaging material web made from a packaging material laminate. The packaging material laminate is a cardboard/plastic laminate comprising a cardboard layer, an aluminium layer and outer printed polyethylene layers. The material web 2 can be unwound from a roll or otherwise fed to the device 1. The material web 2 is transported linearly by the device 1 shown and in this respect preferred. This is not essential, however, but simplifies the representation. With the device 1 shown and in this respect preferred, the material web 2 is driven by a drive roller 3 for which purpose the material web 2 is threaded through a roller gap 4 between the drive roller 3 and a pressing roller 5. The roller gap 4 is narrow enough that a frictional contact between the drive roller 3 and the material web 2 can be provided. The drive roller 3 is driven by a drive 6, in particular an electromotive drive.

[0047] Here the material web 2 is transported to the right and in so doing is guided past a sensor 7 which, in the device 1 shown and in this respect preferred involves an optical sensor 7. If necessary, however, other sensors and/or further sensors can be provided for. The sensor 7 is provided in such a way that it recognises register marks 8 provided on the material web 2 in the form of print marks, when these pass the sensor 7. Once the material web 2 has passed the sensor 7, the material web 2 reaches a processing device 9 with a processing tool 10. The device 1 shown and in this respect preferred, is a processing device 9 for dividing the material web 2 into individual blanks, which can be used as packaging material blanks for the formation of packages, in particular for filling with foodstuffs. For cutting the blanks from the material web 2, the processing device 9 has a processing tool 10 in the form of a processing roller with two cutting blades 11. The processing roller rotates in the transport direction T of the material web 2 so that the cutting blades 11 are guided past a fixed cutting edge 12 provided on the other side of the material web 2 and in so doing sever or cut the material web 2 transversally to the transport direction T. The processing tool 10 is driven by a drive 13, configured here as an electromotive drive.

[0048] Alternatively or additionally, however, other processing tools can be provided which, by way of example, print, perforate, emboss, fold or stamp the material web 2. In addition, instead of print marks, fold lines, punchings, perforations, material differences or other features of the material web 2 can be used as register marks 8. Here, if necessary, it may also be expedient to use a sensor other than an optical sensor 7.

[0049] The drive roller 3 and the processing tool 10 are associated with a roller sensor 14 and a position sensor 15, which capture the position of the associated rollers 3,10 and pass on this position in the form of a signal S to an evaluation device 16. Similarly, the sensor 7 capturing the register marks transmits a signal S to the evaluation device 16, when a register mark 8 passes the sensor 7. Thus, the evaluation device 16 can compare the processing position of the processing tool 10 upon capturing a register mark 8 or the processing position of the processing tool 10 corresponding to a capturing event of a register mark 8 with a predetermined processing position of the processing tool 10 for the capturing event. If in the process a deviation between the actual and the predetermined processing position is established, by means of a regulating device 17 a regulating intervention takes place, which influences the drive 13 of the processing device 9 in such a way that the corresponding deviation of the processing positions is reduced or as far as possible eliminated. In the method shown, and in this respect preferred, this takes place by a brief or pulsed acceleration or deceleration in the speed of the processing tool 10.

[0050] On the basis of the successive capturing events of register marks 8 by the at least one sensor 7, the evaluation device 16 can determine a speed parameter, dependent upon the path velocity of the material web 2 in the region of the at least one sensor 7. The evaluation device 16 correlates the path velocity to the measurement system of the drive roller 3, in that the angle, through which the drive roller 3 continues to rotate between two capturing events, is correlated to the capturing events. Thus, it can be determined if the expected distance between the register marks 8 with regard to time and/or length of the material web 2 corresponds with the actually determined distance between the register marks 8 similarly with regard to time and/or length of the material web 2. If this is not the case because, by way of example, the register marks 8 do not have the predetermined distances between them, slip during transport of the material web 2, or stretching of the material web 2 occurs, via a control device 18 the speed of the processing tool 10 can be adapted accordingly. In addition, separately from this a regulation of the processing position of the processing tool 10 takes place. Both the regulation and the control generate manipulated variables U which, if necessary by superimposing, have an effect on the drive 13 of the processing roller 10 of the processing device 9.

[0051] In FIG. 2, the method described above is shown in somewhat more detail. Identical components are therefore identified with the same reference marks. As reference variable W, a speed of the processing tool 10 (setpoint) can be predetermined and if necessary set to an in particular constant deviation (offset). The intention is to in this way predetermine the speed of the processing tool 10 corresponding to the speed of the drive roller 3 for driving the material web 2. Based on the corresponding reference variable W, a regulator R outputs a manipulated variable U, and the drive of the processing tool 10 is driven accordingly.

[0052] If now a deviation between the predetermined processing position of the processing tool 10 and the actual processing position of the processing tool 10 occurs for a capturing event of a register mark 8 by the sensor 7, the comparator unit D1, in which the information E of the capturing event and information P of the position of the processing tool converge, transmits a signal S dependent upon the amount and sign of the deviation to a position regulation device PR, which adds a corresponding manipulated variable U to the manipulated variable U leaving the regulator R. If, alternatively or additionally, the effective path velocity determined on the basis of the capturing events of the register marks 8 by the sensor 7 does not correspond to the path velocity that would be expected on the basis of the speed of the drive roller 3, the comparator unit D2, in which the information E of the capturing event and information L of the measurement system of the drive roller 3 depending on the amount and sign of the corresponding deviation, provides a signal S to a calculation unit B, which on the basis of the corresponding signal S calculates a correction speed, which is then passed as a reference variable W to a correction speed regulation device KR, which for its part outputs a manipulated variable U, to which the manipulated variable U is added, which has already been determined beforehand.

[0053] A door control T receives information E of the capturing events and on the basis of this and if necessary additionally on the basis of a path velocity parameter, determines a window according to time and/or material web position, in which the next capturing event can be expected, and passes on the information concerning the window as door control information TS to the sensor 7. Outside of this window, no capturing takes place or the respective capturing event is not further processed in the manner described.