EP1860047A1 - Method for regulating sheet tension in a paper producing or treating machine - Google Patents

Abstract

At least two paths run through print unit (03) separate from each other and are then fed to one strand (13). First regulation procedure is used to set tension of two paths to each other. Each path is regulated by its own second control procedure. Both control procedures are separate and use fuzzy logic. INDEPENDENT CLAIM included for device to regulate web tensions.

Description

The invention relates to a method for regulating web tension in a paper-making or processing machine according to the preamble of claim 1.

By the EP 0 837 825 A2 and the EP 0 919 498 A2 a method for controlling the web tension of a plurality of webs is known, wherein based on the respective measured web tension of multiple webs on a fuzzy logic-based control the web tension levels to each other and the web tension in the web course are regulated in terms of minimum / maximum allowable web tension.

From the DE 100 27 471 A1 is a method for controlling web tension in multi-web operation known, initially absolute and relative voltages of the webs are set to each other at the hopper inlet. This is preferably done with the respective intake.

The DE 42 33 855 discloses an apparatus for controlling sheets for the presence of a single or multiple sheet. Here, the evaluation of measured values is based on a fuzzy logic.

The invention has for its object to provide a method for controlling web tension in a papierver- or machined machine.

The object is achieved by the features of claim 1.

The invention provides a system for self-regulating the web tension for multi-lane processing machines, in particular rotary printing machines. It is by its closed control a significant development over currently customary in rotary printing machines web tension control systems. The system is advantageous for triple or double width presses.

The fuzzy-logic-based control concept makes an innovative contribution to greater production reliability and quality consistency in a production that is increasingly cost-less and less manual and cost-intensive. The control system supports the operator when starting the machine, relieves the tension during web tension control during production, and contributes to greater stability in all phases of production.

On the way through the rotary press from reel changer on the intake, the printing units and the superstructure to the folder a paper web has different states of tension (or stress relief or tension profile), the type of paper used (manufacturer, grammage, paper type), the repeated application of ink and possibly fountain solution (in offset), the driven tension elements (infeed with or without dancer roller, tension roller, funnel inlet roller) and speed changes affect the real tension profile of the paper web within the machine. Even more demanding and complex is the regulation of a constant web tension in multi-lane operation. There, in the superstructure, funnel inlet and in the folder also the relative tension of the individual paper webs to each other for optimum web running and printing conditions of importance.

Web tension control systems based on PID controllers are already being implemented on modern newspaper offset presses in the area of reelstands and infeed systems with dancer roller. The downstream drawbars in the machine (after the Printing units and in the hopper inlet) and neighboring aggregates (other reel splicers and infeed units) are, however, not comprehensively included and regulated. Of particular advantage of the invention is therefore the coupling of the tension elements according to the production situation in an overarching, self-regulating web tension system.

With the intelligent web tension control of the invention, both an optimal tension profile of each individual paper web within the machine and optimized tension profiles of the individual paper webs are to be ensured to each other to increase the starting security (avoiding paper tears) to increase the net production output (by less downtime due to disruption ), to achieve a uniform print quality (less register differences) and to improve the running safety in multi-web operation.

In the present scheme, based on the fuzzy logic, the software adjusts the optimum stress level within a paper web, depending on the situation at the hopper inlet and the respective paper profiles, and performs the optimum matching of the webs to one another. By means of paper profiles, d. H. Information on the behavior of the particular type of paper (eg stress-strain characteristics) is taken into account when considering the varietal behavior of each paper web. Expert knowledge is stored in the system to quickly determine the setting logic.

The intelligent control system directly controls the actually measured tension values of the paper webs in the processing machine and not indirectly on strain measurement and control based on engine moments. This brings advantages in terms of efficiency as well as the positive effect on waste, production costs and operator ergonomics.

An important point is that fuzzy technology control relies on expert knowledge and the operator no longer has to make any adjustments. The measured values relating to the production are "caught up" and the relevant aggregates are directly addressed for influencing the voltage. In contrast to a discrete controller, an ideal overall solution is almost always found in the present control system without the need for a specific controlled variable to be maintained exactly and, as a result, a total solution as with the discrete controller may not be achievable. This applies in particular to the single-track controller, which receives a default from the controller looking at all lanes. It is advantageous, however, if the latter works with fuzzy logic to specify if necessary compromise solutions for them specification of the former controller.

Embodiments of the invention are illustrated in the drawings and will be described in more detail below.

Fig. 1

eine Druckmaschine mit mehreren Bahnen;

Fig. 2

eine schematische Darstellung einer Regelung mit zwei Regelprozessen;

Fig. 3

eine schematische Darstellung der Regelung der Druckmaschine aus Fig. 1;

Fig. 4

eine grafische Darstellung des Verlaufs der Bahnspannung einer Bahn entlang ihres Weges;

Fig. 5

ein Ablaufdiagramm des bahnbezogenen Regelprozess;

Fig. 6

eine schematische Darstellung eines Zuordnungsdiagramms;

Fig. 7

ein Ablaufdiagramm des mehrbahnbezogenen Regelprozess.

Show it:

Fig. 1

a printing machine with multiple webs;

Fig. 2

a schematic representation of a control with two control processes;

Fig. 3

a schematic representation of the control of the printing press of FIG. 1;

Fig. 4

a graphical representation of the course of the web tension of a web along its way;

Fig. 5

a flow chart of the web-related control process;

Fig. 6

a schematic representation of an assignment diagram;

Fig. 7

a flow chart of the multi-course control process.

Fig. 1 shows a path of several, at least two tracks B1; B2; B3; B4, z. B. web B1; B2; B3; B4, z. B. paper web B1; B2; B3; B4 by a processing machine, in particular printing machine, with the web tension substantially influencing, schematically illustrated units:

The railway B1; B2; B3; B4, exemplified at the track B1, is from a supply 01, z. B. a roll change 01, fed and passes through at least one traction device (or braking device) 02 for promoting and setting a web tension, z. As a retraction 02, before they have a processing stage 03, z. B. at least one printing unit 03 with one or more printing units, passes through. The retraction unit 02 can simultaneously represent an actuator 02 for adjusting the voltage before the printing unit 03. After a last printing location assigned to the web B1, it passes through a measuring point 04 (nDE: according to printing unit 03) for determining the web tension and subsequently an actuator 05 influencing the web tension, eg a draw roller 05 or roller / draw group 05. In a superstructure, not shown can be arranged turning bars and longitudinal cutting devices, through which either uncut paths B1 turned or overturned, or trains B1 can first be cut and then turned or overturned. Prior to the entry of the web B1 (or the sub-webs) into a so-called harp 07 (a plurality of deflecting rollers associated with a plurality of webs B1, B2, B3, B4 or sub-webs), for each web B1 (or each sub-web) one Measuring point 06 (vTE: before funnel inlet) is provided for determining the web tension. The measuring point 04 "after the printing unit" thus means a measuring point 04 in front of the tensioning element 05 following the printing unit 03 or at least in front of a possibly present cutting and / or turning device. After the harp 07, the web B1 (or its partial webs) together with other webs B2; B3; B4 (or their partial webs) merged into one or more strands 13, pass through Another the web tension influencing actuator 08, a tension roller 08 or roller / Zuggruppe 08, z. As a so-called. Funnel inlet roller 08 before they are longitudinally folded, for example, by one or more funnel 09. The measuring point 06 "upstream of hopper inlet or harp" thus means a measuring point 06 for the individual web or partial web before the merging of webs or partial webs on the funnel inlet roller 08 (or another upstream roller assigned to a plurality of webs) and after the tension element 05 or, if present, after a cutting and / or turning device. If the product is not wound up again, the webs pass through B1; B2; B3; B4 (or partial webs) in the strand 13 another the web tension influencing actuator 10, another tension roller 10 or roller / tension group 10, z. B. Falzzugwalzen 10, and are folded at least once in at least one folder 11. The aforementioned retraction unit 02 has an actuator 16 which influences the web tension, a tension roller 16 or roller / tension group 16 or dancer roller 16 and possibly a separate measuring point 14 for determining the web tension (vDE: before printing unit 03). The actuator 16 and the measuring point 14 can also be arranged between the roller change 01 and the printing unit 03 without being combined to form a retraction unit 02. The separate measuring point 14 may be omitted if there is already adequate information about the present voltage via the actuator 16, for example as an actuator 16 which can be actuated by means of a pressure medium.

In the printing press shown in FIG. 1, funnels 09 are exemplarily provided with webs B1; B2; B3; B4 fed from different sides arranged printing units 03, wherein the funnel structure a plurality of funnels 09 can side by side and / or each other, and a plurality of the tracks B1; B2; B3; B4 strands formed 13 may be performed on more than one folder 11. Also, the tracks B1; B2; B3; B4 not in each case in the manner schematically illustrated by a respective pressure unit 03 through, but can, for. B. after passing through a part of a printing unit 03 out of this out and either equal to the superstructure or another Printing unit 03 are supplied for further processing. It is essential, however, that the measuring points 04; 06; 14 and the actuators 05; 10; 16 for the below explained in more detail scheme the tracks B1; B2; B3; B4 are assigned or become.

In Fig. 1 by arrows through the measuring points 04; 06; 14 signals S1.1 obtained; S1.2; S1.3 of the web B1, S2.1; S2.2; S2.3 of the track B2, etc. indicated. Also in the area of the roll changer 01, if necessary, a voltage descriptive signal S1.0; S2.0; S3.0; S4.0 (dashed) of an unmarked measuring point. Next are the default values for the actuators 16; 05; as signals S1.11; S1.12 for the track B1, S2.11; S2.12 for the railway B2 etc. with arrows. The signal Sx.11 represents, for example, a default value (set value) for the web tension in the feed unit 02, the signal Sx.12 a default value (setpoint) for the lead of the draw roller 05. The signals S0.13; S0.14 set the default values (setpoints), z. An optionally existing default value (setpoint) for the web tension in the area of the roll changer 02 is denoted by S1.10 for the web B1, S2.10 for the web B2, etc. ,

1 has a control system 17 whose concept is first explained in principle with reference to FIG. 2, and in FIG. 3 with direct reference to the regulation of the web tension of a plurality of webs B1; B2; B3; B4 of Figure 1, at least a plurality of at least one funnel inlet roller 08 accumulating tracks B1; B2; B3; B4 (or partial webs), is shown.

The control system 17 has two mutually different types of controllers 18 and 19 with two mutually different subtasks (control processes). These two "types" of controllers 18 and 19 may be spatially separated as distinct hardware components, as different software programs communicating with each other, or as two processes or subroutines or subroutines in a software program. Unless explicitly stated otherwise, in the following the terms controller 18; 19 or control processes 18; 19 under the same reference numerals and should be understood for all of the above and other suitable ways of implementing the same. As shown in Fig. 2, the control system comprises a plurality of (here two) regulators 18.1; 18.2, which each receive actual values from a respective sub-process, and generate one or more manipulated variables for the considered sub-process on the basis of their implemented logic. The controllers 18 are superordinated by the controller 19, which receives actual values from the subprocesses, by means of its implemented logic set values for the subordinate controllers 18.1; 18.2 as well as possibly to the entire process directed manipulated variables outputs. There is no mutual interaction or communication between the controllers 18 and 19. Although they can work simultaneously, they work in principle independently of each other, although they sometimes consider the same process values (actual values) and the control process 19 generates specifications (setpoint specifications) for the control processes 18 ,

Also shown in FIG. 2 are memory means 21, from which, prior to the start of the processes, start values are input to the controllers 18; 19 can be read. The start values are advantageously read from a common memory unit 21.

3, at least two measured values of each of the involved web paths, namely the measured value S1.2; S2.2; S3.2; S4.2 for the voltages, z. B. of measuring rollers 04 performed as measuring point 04, (directly) after the respective printing unit 03 and the measured value S1.3; S2.3; S3.3; S4.3 fed from the respective measuring point 06 before the funnel inlet or the harp 07. This applies in the case of the measured values S1.3; S2.3; S3.3; S4.3 and the measuring point 06 also assigned to this funnel inlet turned partial webs. In a further development, the control system 17 can, if necessary, also receive the signal S1.1; S2.1; S3.1; S4.1 be supplied for the voltage in each case before the printing unit 03 (dashed lines). The measurement of the voltage takes place in each case, for example, by the web B1; B2; B3; B4 wrapped measuring rollers.

The control system 17, at least the controller 18, preferably controls and optimizes the web tensions using fuzzy logic. The input variables such. Eg the measured values S1.3; S2.3 etc. for the voltages (possibly scaled accordingly) of a lane B1 are fuzzified, i. H. are used as input values for functions defined in sections, each describing a term (linguistic size range, eg, large, medium, small). The function value is the degree to which the input value satisfies the linguistic meaning of the term or, in the case of overlapping of the value ranges, the degrees of fulfillment. In the subsequent defuzzification of the degrees of fulfillment of the individual terms of the linguistic variables is a sharp initial value, z. B. generates a corresponding signal to an actuator or a new setpoint for an actuator. Depending on the result of the defuzzification, one actuator, another actuator, or several actuators may be preset. Which rules are applied is determined by the degrees of fulfillment of the terms of the input variables. An o. G. Example with the two input variables (eg measured values S1.3, S1,2) and one output variable (eg signal S1.12 to an actuator, eg the roller / pull group 05) for z. B. tabular present, held rules, graphically z. B. represent as a three-dimensional map. If more input quantities enter a decision process and / or if several output quantities are to be generated, the "maps" are correspondingly multidimensional. The controller 19 need not be based on fuzzy logic, but may otherwise be discrete, e.g. be executed as a PID controller 19. Another advantage is the version with fuzzy logic.

The control system 17 has, as generally shown above, the two mutually different controllers 18 and 19 with two mutually different subtasks, wherein the controller 18, the web tension of a single track B1; B2; B3; B4 controls in its course and in terms of limits, and the controller 19, the voltage level, in particular the voltage level in front of the hopper roller 08, the tracks there guided together B1; B2, B3; B4 sets relative to each other.

The control system 17 has at least a number of regulators 18 which correspond to the number of tracks B1; B2; B3; B4 (or partial webs) corresponds. The regulators 18 all have the same architecture or are programmed in the same way and are used for the four tracks B1 shown in FIGS. 1 and 2; B2; B3; B4 with 18.1; 18.2; 18.3; 18.4. The four controllers 18.1; 18.2; 18.3; 18.4 or processes 18.1; 18.2; 18.3; 18.4, the controller 19 or control process 19 is assigned.

For starting operations, it is advantageous if the control system 17 start values are specified as setpoints, which z. B. provide meaningful starting points for certain web guides. In the example, therefore, the controllers 18.1; 18.2; 18.3; 18.4; 19 start values S1.11_0; S1.12_0; S2.11_0; S2.12_0; S3.11_0; S3.12_0; S4.11_0; S4.12_0; S0.13_0 and / or S0.14_0 for the signals S1.11; S1.12; S2.11; S2.12; s3.11; S3.12; s4.11; s4.12; S0.13 and / or S0.14 (voltages or overfeeds). These are for example kept in a memory and may be pending from the selected production and / or the web material.

In the operation of the control system 17 is now in a first subtask by means of the controller 18.1; 18.2; 18.3; 18.4 or processes 18.1; 18.2; 18.3; 18.4 each track B1; B2; B3; B4 initially considered alone considered, so that the voltage at the measuring point 06 before the funnel inlet between a minimum, z. MIN = 8 dN / m, and a maximum, e.g. B. MAX = 60 dN / m. A second requirement of the first sub-task may consist in the gradation shown schematically in FIG. 4 in the voltages at the measuring points 14 (before the printing unit 03), 04 (after the printing unit 03) and 06 (before the funnel inlet or before the funnel) To merge). In addition, the process-related minimum voltages (eg 8daN) and maximum voltages (eg 60daN) must be observed. The task of the controller 18.1; 18.2; 18.3; 18.4 or processes 18.1; 18.2; 18.3; 18.4 it is thus, the tension of the single track B1; B2; B3; B4 on the funnel inlet, in particular on their way to get there, in the principle allowed range and additionally possibly the correct grading within the path of the individual track B1; B2; B3; To achieve B4.

To solve this subtask, the controllers 18.1; 18.2; 18.3; 18.4, in the following exemplarily for the controller 18.1 of the web B1, in each case at least two signals S1.2 (after the printing unit 03) and S1.3 (before the funnel inlet or merging) are fed to the measured tension of the same web B1. The controller 18.1 processes these input variables in the o. G. Art by means of fuzzy logic and generates an output signal S1.11, which acts on the actuator 16 of the feed unit 02. In the simplest embodiment of the controller 18.1 or of the process 18.1, only the two o. G. Input signals S1.2; S1.3 and given an output signal S1.11 to only the actuator 16 before the printing unit 03. Optionally, the controller 18.1 can additionally be supplied with the signal S1.1 for the measurement of the voltage before the printing unit 03, and be processed in the logic.

In an advantageous solution, the controller 18.1 with a signal S1.12 also acts on the actuator 05 behind the printing unit 03, z. B. by determination and specification of suitable Voreilungswerten. In this embodiment, an improved adjustment of the voltage curve over the path of the web B1 is possible. The rule concept takes place here z. B. in such a way that first by means of the actuator 16 is trying to meet the conditions of the minimum / maximum voltages and at the same time the desired voltage waveform. If this is not possible solely by acting on the actuator 16, the actuator 05 is included.

FIG. 5 illustrates the sequence for the control processes 18.x using the example of the control process 18.1, essentially self-explanatory. Without repeating again above, it becomes clear that a default value, in particular for the measuring point 06 before the funnel inlet, is read from the control process 19 , This current default value is the last one valid and changed in deviation one or more for the subsequent calculations underlying assignment diagrams, in particular postponed. The following calculations, for example, a setpoint shift for the retraction unit 02 and / or the calculation of a Zugwalzenverstellung the pulling device 05 then take place on the basis of unmodified or modified mapping diagrams or the unchanged or modified mapping diagram based on fuzzy logic after the measured values S1.2. , S1.3 and S1.1 if necessary. At the start of production of the machine 19 starting values are read from a memory device 21 instead of the default values from the process. The subprocess prior to querying the machine state (in production?) Is part of the initialization of the system. The queries are answered in the diagrams with "true" (w) or "false" (f). The connection with the arrow from the lowest node of the process to the node before the query for the machine status makes it clear that this is a process that is constantly being run as long as the machine is in production.

Schematically, in Fig. 6, the principle of o.g. Change or shift of an assignment diagram shown. A measured value Sm has first values for the weighting of "small" and "medium" in a first state of the diagram. Once the assignment functions have been shifted (section-wise defined), the measured value Sm is offset by weights "small" and "medium" that deviate therefrom. This change in the weighting now finds expression in the overall consideration of all fuzzy rules and possibly ultimately leads to a setpoint shift for the control variable under consideration, here e.g. the manipulated variable S1.11 for the retraction unit 02.

In a second sub-task is checked by the controller 19 and the control process 19, if the voltage in front of the harp 07 of the tracks to be led together B1; B2; B3; B4 to each other in the desired ratio and this regulated accordingly. So should z. B. the lowest on the tension roller 08 coming to train B1; B2; B3; B4, here Path B3, a higher voltage than the overlying, etc. The second task is therefore, the voltages of the superimposed tracks B1; B2; B3; B4 to each other in the field of funnel inlet graduate or align. In this case, the minimal requirement applies that S _n ≥ S _{n + 1} for all S1.3; S2.3; S3.3; S4.3 etc., if n is a path B1; B2; B3; B4 and n + 1 the outwardly adjacent track B1; B2; B3; B4 denotes. As a boundary condition applies to all lanes B1; B2; B3; B4: MAX ≥ S ₁ ≥ S ₂ ≥ S ₃ ≥ S ₄ ≥ MIN, when the index is the order of lanes B1; B2; B3; B4 in the region of the funnel inlet roller 08 from the inside out. In addition, there is advantageously a rule for the optimal state, which states: S _n ≥ S _{n + 1} + ΔS, with z. B. ΔS = 2daN / m.

In the second subtask (or first control process 19), the voltages of the different orbits z. B. varies in such a way that for all webs B1; B2; B3; B4 the tension in front of the funnel inlet roller 08 is within the tolerance range (FIG. 4, before funnel inlet (vTE)). For this purpose, the controller 19 parallel to the controller 18.1; 18.2; 18.3; 18.4 the signals S1.3; S2.3; S3.3; S4.3 supplied the measured values for the web tension. The controller 19 or control process 19 is also based on a fuzzy logic in a development, by means of which from the input variables (signals S1.3, S2.3, S3.3, S4.3) default values for the controller 18.1; 18.2; 18.3; 18.4 and signals S0.13 and S0.14 are generated for the interacting with the strand 13 actuators 08 and 10 as output variables.

Again, essentially self-explanatory, the sequence for the control process 19 is shown. As can be seen, the actual sub-process for the balancing of the voltages Sx.3 can be preceded by a sub-process which, as shown, is based on the individual measured values Sx.3 checks the total web tension level and possibly on the adjustment (eg the lead) of the funnel inlet roller 08 which raises or lowers the overall level for all on this roller 08 running tracks / partial webs. The sub-process includes the steps Read measured values - check total web tension level - and, depending on the result, calculate and output the adjustment of the hopper inlet roller (f) or leave it in this position (w).

In the case of deviation (f) from one another of the predefined relationship (MAX ≥ S1.3 ≥ S2.3 ≥ S3.3 ≥ S4.3 ≥ MIN) to each other and / or to the limit values, default values for the respective control processes 18 become. x or the respective control process 18.x, in particular for the measuring point 06 before the funnel inlet, calculated and output. Again, the calculation can be done via fuzzy logic, e.g. in turn the calculation underlying assignment diagrams are shifted according to the deviations. At the start of production of the machine 19 starting values are read from a memory device 21 instead of the default values from the process. The subprocess prior to querying the machine state (in production?) Is part of the initialization of the system.

The controller 19 or control process 19 takes in an advantageous embodiment, no direct influence on the individual web B1; B2; B3; B4 associated with actuators 16; 05, but is based on his map from the signals S1.3 to S4.3 the controllers 18 specifications. This requirement refers only to the front of the hopper roller 08 per track B1; B2; B3; B4 voltage to be respected, ie a setpoint for the z. B. at the measuring points 06 voltages to be respected. These default values are incorporated in the controller 18.x, for example by changing the position and / or form of the terms with regard to the input variables during fuzzyfication (see above). Thus, an individual track B1 to B4 associated actuator 02, 05; 16 not indiscriminately addressed by two different processes, which would result in a restless or even unstable control behavior. In contrast, the request from the rule process 19 is taken into account within the rule process 18.x. The advantageous embodiment of this sub-process in the controller 18.x as fuzzy logic now makes it possible that the requirement or specification from the controller 19 does not necessarily have to be enforced exactly as specified, but a consideration in the context and in the light of the entire control task of the controller 18.x is made. Only the assignment diagrams relating to the specification from controller 19 are moved and these newly evaluated criteria are taken into account in the determination of the optimal (or at least permissible) overall state. The connection with the arrow from the lowest node of the process to the node before the query of the machine status makes it clear that this is a process that is continuously run as long as the machine is in production.

These two control processes 18 and 19 or the associated subtasks are cyclically repeated and according to the measurement results and the results from the logic of the web tension influencing aggregates, for. B. draw rollers 16; 05; 08; 10, or not shown dancer rolls etc. acted upon. In addition to the o. G. Aggregates such as in the infeed 02 and / or one or more draw rollers 16; 05; 08; 10 may also be additional facilities in the roll changer 01 and / or facilities in the folder 11. The above-mentioned to Fig. 3 is then to corresponding signals, for. B. S1.10, for the reelstand 01, or not shown signals for the folder 11 to complete.

The control of such aggregates by the control system 17 is carried out in an advantageous embodiment, taking into account a priority: So z. B. as described above by the control system 17 in a first priority, the setpoint specification made only for the retraction 02. If only the two above-mentioned tasks can not be fulfilled with this measure, an action on the draw roller 05 follows the printing unit 03. it is allowed in a third stage to influence the funnel inlet roller 08. In this case, however, the level of all participating lanes B1; B2; B3; B4 moved. The actuators Zugwalze 05 and Trichtereinlaufwalze 08 are only used if the global web tension over all tracks B1; B2; B3; B4 is not correct, or if the adjustment range of the intake 02, or its actuator 16, for the desired web tension is not sufficient.

Is the requirement of the second subtask, d. H. the desired gradation, not achievable, the logic of the control system 17, in particular of the controller 19, may be designed to aim for an optimized state approaching the ideal state as close as possible. Even acceptable limits for the deviation (relative or absolute) can be predetermined and possibly changed. In addition, in an advantageous development, the control system 17 may be configured to issue a warning in the event of a strong deviation from the permissible tension profile (of a web) or the gradation (of all webs relative to one another) and, if necessary, bring about a shutdown of the processing machine in the event of an unauthorized high deviation.

However, in the simplest embodiment, the control system 17 operates with two measurement locations for the voltage per rail B1 involved; B2; B3; B4, in each case after the printing unit 03 and before the funnel inlet, wherein the action is carried out in each case initially at the retraction unit 02 and possibly in the second step in the region of the draw roller 05.

As already mentioned above, after cutting a web B1; B2; B3; B4 a plurality of web splitter 01 associated partial webs are guided on different ways to the hopper 09. In this case, each partial web, the voltage before the funnel inlet, z. B. determined in each case a separate measuring point 06. These, a common reel changer 01 associated measurements, eg. B. S1.3a and S1.3b, either before they are fed to the control system 17 or in the control system 17, ie in the controller 18 and the controller 19, linked to a value, for. B. averaged with or without weighting, and the resulting value used as an actual value for regulation. This link can be shown as a logical block 22 or sub-process 22 shown by dashed lines in an exemplary manner for the controller 18.1 and 19 in the respective controller 18; 19 be integrated.

The reel changer 01 and the retraction unit 02 preferably have, in addition to the control system 17, a closed control, to which a desired value is preset by the control system 17. The draw rollers 05; 08; 10; 16 are from the control system 17 z. B. only with respect. Their override (speed, angular position) controlled.

In the following, the aggregates involved for influencing the voltage are specified in their advantageous embodiment:

The intake system 02 has a closed loop ("closed loop" control), the setpoint specification by the control system 17, in particular by the controller 18 is maintained safely. It acts on the entire track B1; B2; B3; B4 and represents the most important actuator. In an advantageous embodiment, the retraction means 02 as an actuator 16 against the traction of the web B1; B2; B3; B4 movable roller, which counteracts by means of pressure medium of a predetermined pressure of the web tension. In this case, no separate measuring point 14 is required if the correlation between the applied pressure and the resulting web tension is known.

The tension roller 05 can by changing the lead over the paper web speed to the web tension of the current web B1; B2; B3; B4 act here and represents the last possibility before the hopper inlet roller 8, a single web B1; B2; B3; B4 in their tension or gradation to influence.

The hopper inlet roller 08 can by changing the lead over the paper web speed to the web tension of all webs B1; B2; B3; B4 work.

The Falzzugwalze 10 can also by changing the lead over the paper web speed on the web tension of all webs B1; B2; B3; B4 work. It has a direct impact on the cut register.

A z. B. Modular design makes it possible to extend the control over several lanes, for each further lane B1; B2; B3; B4, in the case of a hardware-separated solution, only another controller 18, z. As a fuzzy PLC with program to be added. The program of the controller 19, z. As the master PLC, must also be informed that there is another track B1; B2; B3; B4 must involve.

In a pure software solution for the controllers 18 and 19 has to be extended by a path B1; B2; B3; B4 only expanded the software by a control process 18.x, and the program of the control process 19 are communicated.

The regulation by the regulators 18 and 19 may be parallel in purely sequential or temporal terms, but with regard to the voltage to be set in front of the hopper inlet roller 08, e.g. at the measuring points 06, the control is built hirarchisch and the controller 19 is superordinate to the controllers 18.

In an advantageous embodiment, the control system 17 is designed so that a found by the control system 17 setting for a particular configuration of the print job, a web path and / or a specific product can be converted as default values in the storage device, so that they in future at the same or similar Production situation can be read as start values. For example, the takeover of the product or production data from the machine control and / or product planning takes place for this purpose. The adoption as new starting values can be triggered, for example, by the decision of the operating personnel, or else by the system itself, if the control system and / or the control system are designed as a self-learning system with regard to this function.

LIST OF REFERENCE NUMBERS

01

Supply, roll changer

02

Actuator, pulling / braking device, intake

03

Processing level, printing unit

04

Measuring point for web tension after printing unit

05

Actuator, draw roller, roller / pull group

06

Measuring point for web tension before hopper inlet

07

harp

08

Actuator, draw roller, roller / pull group, hopper inlet roller

09

funnel

10

Actuator, tension roller, roller / tension group, folding tension roller

11

folding

12

-

13

Strand with several paper webs

14

Measuring point before printing unit

15

-

16

Actuator, tension roller, roller / tension group, dancer roller

17

control system

18

Controller, control process

19

Controller, control process

20

-

21

memory device

22

Building block, sub-process

B1

Railway, material web, paper web

B2

Railway, material web, paper web

B3

Railway, material web, paper web

B4

Railway, material web, paper web

S1.1

Signal, measured value of web tension before printing unit of web (B1)

S1.2

Signal, measured value of the web tension according to the printing unit of the web (B1)

S1.3

Signal, measured value of web tension before hopper inlet of web (B1)

S1.10

Signal, default value for the web tension in the reel changer of the web (B1)

S1.11

Default value for the web tension in the infeed train of the web (B1)

S1.12

Default value for the advance of the draw roller of the web (B1)

S2.1

Signal, measured value of web tension before printing unit of web (B2)

S2.2

Signal, measured value of the web tension according to the printing unit of the web (B2)

S2.3

Signal, measured value of web tension before hopper inlet of web (B2)

S2.10

Signal, default value for the web tension in the web splicer (B2)

S2.11

Signal, default value for web tension in web infeed (B2)

S2.12

Signal, default value for the advance of the draw roller of the web (B2)

S3.1

Signal, measured value of web tension before printing unit of web B3

S3.2

Signal, measured value of web tension after printing unit of web B3

S3.3

Signal, measured value of web tension before hopper inlet of web B3

S3.10

Signal, default value for the web tension in the reel changer of web B3

s3.11

Signal, default value for the web tension in the infeed train of the web B3

S3.12

Signal, default value for the advance of the draw roller of the web B3

S4.1

Signal, measured value of the web tension before the printing unit of the web (B4)

S4.2

Signal, measured value of the web tension according to the printing unit of the web (B4)

S4.3

Signal, measured value of web tension before hopper inlet of web (B4)

S4.10

Signal, default value for the web tension in the web splicer (B4)

s4.11

Signal, default value for web tension in web infeed (B4)

s4.12

Signal, preset value for the advance of the draw roller of the web (B4)

S0.13

Signal, default value for advancing the hopper pickup roller

S0.14

Signal, default value for the advance of the folder tension roller

S1.3a

reading

S1.3b

reading

S1.0

Signal, measured value of the web tension in the area of the reel changer (01)

S2.0

Signal, measured value of the web tension in the area of the reel changer (01)

S3.0

Signal, measured value of the web tension in the area of the reel changer (01)

S4.0

Signal, measured value of the web tension in the area of the reel changer (01)

18.1

regulator

18.2

regulator

18.3

regulator

18.4

regulator

x

Placeholder for railway (B1, B2, B3, B4)

nDE

after printing unit (03)

VTE

before funnel inlet

vDE

before printing unit (03)

VEW

in front of the intake

Claims (9)

A method of controlling web tension in a papermaking machine wherein a web tension (S) is controlled by an actuator (02; 05; 16) by a control system (17) using fuzzy logic with respect to at least one measured value (Sx .3) is regulated by means of a regulation and / or a characteristic diagram, characterized in that by means of a first control process (19) an adjustment of the voltage level to be merged tracks (B1, B2, B3, B4) relative to each other, and by means of a second, from the first A control of the web tension of a single web (B1, B2, B3, B4) in its course and with regard to limit values takes place in the first control process (19) on the basis of a first rule and / or one first characteristic field, a default value for a web tension is generated, this default value is supplied to the second, using fuzzy logic operating control process (18), and by means of Vorg a change of a position and / or form of at least one term of a linguistic description of a fuzzyfication in the second control process (18) is effected. A method according to claim 1, characterized in that the first control process (19) operates using fuzzy logic. A method according to claim 1, characterized in that the first control process (19) is directed to the adjustment of the voltage level in front of the funnel feed roller (08) of the tracks (B1; B2, B3; B4) guided there relative to one another. Method according to Claim 1, characterized in that the voltage of individual tracks (B1, B2, B3; B4) at the funnel inlet in each case in the generally permitted range is adjusted. Method according to Claim 1, characterized in that the first and second control processes (18; 19) operate independently of one another, wherein the first control process (19) generates setpoint specifications for the second control process (18). A method according to claim 5, characterized in that the first and second control processes (18; 19) partially consider the same process values. Method according to Claim 1, characterized in that a plurality of first control processes (18.1; 18.2; 18.3; 18.4) each have at least two signals for the measured voltage of the same web (B1), namely after the printing unit (S1.2) and before merging ( S1.3) is supplied. Method according to Claim 1, characterized in that the first control process (19) checks whether the tension in front of a harp (07) of the tracks (B1; B2; B3; B4) to be brought together is in the desired ratio to one another, and this is regulated by the first control process (19) accordingly. Method according to Claim 1, characterized in that the controller (19) has the signals (S1.3; S2.3; S3.3; S4.3) of the measured values for the web tension parallel to the controller (18.1; 18.2; 18.3; 18.4) the webs (B1; B2; B3; B4) are fed before being merged.

Images