Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
  • B65H—HANDLING THIN OR FILAMENTARY MATERIAL, e.g. SHEETS, WEBS, CABLES
  • B65H18/00—Winding webs
  • B65H18/08—Web-winding mechanisms
  • B65H18/26—Mechanisms for controlling contact pressure on winding-web package, e.g. for regulating the quantity of air between web layers
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
  • B65H—HANDLING THIN OR FILAMENTARY MATERIAL, e.g. SHEETS, WEBS, CABLES
  • B65H23/00—Registering, tensioning, smoothing or guiding webs
  • B65H23/04—Registering, tensioning, smoothing or guiding webs longitudinally
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
  • B65H—HANDLING THIN OR FILAMENTARY MATERIAL, e.g. SHEETS, WEBS, CABLES
  • B65H2301/00—Handling processes for sheets or webs
  • B65H2301/40—Type of handling process
  • B65H2301/41—Winding, unwinding
  • B65H2301/414—Winding
  • B65H2301/4148—Winding slitting
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
  • B65H—HANDLING THIN OR FILAMENTARY MATERIAL, e.g. SHEETS, WEBS, CABLES
  • B65H2511/00—Dimensions; Position; Numbers; Identification; Occurrences
  • B65H2511/10—Size; Dimensions
  • B65H2511/13—Thickness
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
  • B65H—HANDLING THIN OR FILAMENTARY MATERIAL, e.g. SHEETS, WEBS, CABLES
  • B65H2511/00—Dimensions; Position; Numbers; Identification; Occurrences
  • B65H2511/10—Size; Dimensions
  • B65H2511/14—Diameter, e.g. of roll or package
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
  • B65H—HANDLING THIN OR FILAMENTARY MATERIAL, e.g. SHEETS, WEBS, CABLES
  • B65H2515/00—Physical entities not provided for in groups B65H2511/00 or B65H2513/00
  • B65H2515/30—Forces; Stresses
  • B65H2515/31—Tensile forces
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
  • B65H—HANDLING THIN OR FILAMENTARY MATERIAL, e.g. SHEETS, WEBS, CABLES
  • B65H2515/00—Physical entities not provided for in groups B65H2511/00 or B65H2513/00
  • B65H2515/30—Forces; Stresses
  • B65H2515/34—Pressure, e.g. fluid pressure
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
  • B65H—HANDLING THIN OR FILAMENTARY MATERIAL, e.g. SHEETS, WEBS, CABLES
  • B65H2557/00—Means for control not provided for in groups B65H2551/00 - B65H2555/00
  • B65H2557/20—Calculating means; Controlling methods
  • B65H2557/264—Calculating means; Controlling methods with key characteristics based on closed loop control
  • B65H2557/2644—Calculating means; Controlling methods with key characteristics based on closed loop control characterised by PID control

Definitions

• this paper web goes through a slitter for assembly according to customer-specific specifications, on which it is cut into paper web widths of different widths and wound onto cores that can be delivered to customers.
• the winding hardness or the winding hardness is usually used as a measure for assessing the quality of the resulting roll.
• the average layer thickness during the reeling process, the number of layers wound and the increase in radius are determined here. Averaged over typically 100 layers, the average layer thickness is obtained in this way. In order to be able to better compare the average layer thickness between individual types of paper, this size is related to the paper thickness in the relaxed state of the respective type. You get a key figure that is usually less than 1. The smaller it is, the harder the roll is wound; in this context one speaks of a high winding hardness. In the other case, the average normalized layer thickness is relatively large, which corresponds to a low winding hardness.
• a reel hardness is defined with respect to the reel. It can be seen from the curves in FIG. 2 that the roll-up winding curve (AU) and the roll-off roll curve (AB) influence one another, and despite the force relationships which are constantly regulated during the winding process, the roll-up curve follows the roll-up curve of the reel in its course. Such behavior of the paper roll during the reeling process, however, is not desired, as described at the beginning.
• the problem underlying the invention therefore consists in specifying a method and an arrangement by means of which a paper winding parameter which is decisive in the paper winding process can be predicted or regulated.
• the behavior of the paper and the associated paper winding parameters are similar when unwinding and winding up different paper rolls. This fact can be used to train a predictor or to impress this behavior on him in order to be able to predict the behavior of the paper wrap parameter for future winding processes.
• the result of the prediction of the paper winding parameter can advantageously be used to influence the forces that are usually kept constant in paper winding devices in accordance with the desired target paper winding parameter by impressing the influence-dependent behavior of the paper winding parameter on a controller and one of the target winding parameter and the predicted current one Paper winding parameter formed control difference is supplied, from which it determines a compensation force that is superimposed on a decisive force during the winding process.
• the method and the arrangement can also be used advantageously if the paper is wound from a larger roll to a smaller roll and the paper is thereby cut into webs.
• simple measured variables such as the radius of the paper or the angular velocity of the different paper rolls, are advantageously detected in order to predict the current paper winding parameter or to determine the layer thickness from these variables.
• the proposed methods and arrangements can be used particularly advantageously both for regulating the line force and for regulating the web tensile force as an influencing force.
• Neural networks can advantageously be used as a predictor and PID controllers can be used as controllers, since there is sufficient experience with these devices and no great effort is required to train or adapt these devices to the specific problems associated with paper winding.
• the proposed arrangements can advantageously be used in paper roll cutters, since there are high quality requirements and an improvement can be achieved by means of the proposed methods.
• the proposed method and the proposed arrangement can also be used advantageously with paper-like materials that have similar mechanical properties, ie. H. exhibit viscoelastic behavior and elastic / plastic deformation, such as paper.
• Figure 1 shows a schematic representation of a
• FIG 2 shows roll-up and roll-off curves.
• Figures 3 and 4 show force-layer thickness relationships
• Figure 5 shows a control loop for a winding
• FIG. 6 shows a control loop for several winding stations.
• Figure 1 shows schematically the structure of a backup roller winder with the radius r as the winding radius, F as the web tension in front of the backup roller St and the web speed v.
• the paper web is denoted by P and F ⁇ is the wrapped-in web tensile force or also the web force on the reel.
• MJJ denotes the driving torque of the center drive of the winding tube
• Mg denotes the driving torque of the back-up roll, the winding being designated Wi and the tube being Hui.
• a line force Lin occurs which can be influenced by mechanical devices.
• Several paper webs are already wound on top of each other on the wrap Wi, which is indicated by concentric circles.
• the first paper roll which represents the drum, is not shown, but only the second paper roll Wi on which the paper web P is wound.
• the first paper roll from which it is unwound is located in front of it in the direction of the force F and corresponds essentially to the second roll, whereby it can differ from it by its width.
• the web force F ⁇ depends on the control variables and other influencing variables such. B. the paper and the environment.
• Control variables are, for example, the drive torques Mg of the support roller St and the center drive M ⁇ , the line force Lin with which the winding Wi is pressed onto the support roller St the web tension in front of the nip F, as well as occasional friction damper settings, with which vertical movements of the angle Wi on the support roller St are damped by hydraulic dampers or by eddy current brakes.
• Influencing variables are, for example, the paper properties, such as the modulus of elasticity, the weight per unit area in relation to the density, the roughness, the smoothness, the moisture, the porosity and the elongation at break of the paper. as well as geometry data such as the paper web widths are taken into account.
• the course of a roll-up layer thickness curve AU follows the course of the roll-off layer thickness curve AB of the tambour.
• the normalized roll-up layer thickness or roll-off layer thickness to the right is the diameter of the paper roll on which the roll is applied.
• the roll-up thickness curve AU emulates the course of the roll-off thickness curve of the spool, although with conventional methods the influencing force, which can be the line force or the web tensile force, is kept constant.
• Paper winding devices that are particularly common in practice are reel cutters on which produced paper that has been stored on reels is customized. Such machines have a large number of setting options and parameters, which are shown below.
• Machine data Edge trimming, curve number web train, braking time, number of reel machine, basis weight, maximum speed, throw number, paper type, curve number friction damper, curve number speed, trim.
• Reel data core diameter, reel diameter, average winding hardness, curve number, length of reel, knife number, reel number, station number, width of the reel • Reel data: reel diameter, reel length, reel number
• Curve telegrams (basic / target and actual curves) station-independent curves: web tension, speed, friction damper pressure, compensation pressure (inside / outside), current main drive, current brake generator, winding hardness drum,
• the machine data contain general information for the winding process.
• the role data are preferably provided for each role produced.
• Curve telegrams provide information about target and actual curves. These are essentially the web tension, speed and line force curves. In particular, for slitter reels with several stations distinguish between curves that are the same for all stations and those that are station-specific.
• the measurable data on these paper winding devices are currently made available as a function of the diameter, but it is also conceivable to provide them as a function of the time or other measured quantities of the device.
• Figures 3 and 4 show, for example, the courses of different stations of a paper roll cutter.
• the influencing force is the web tension and upwards the average layer thickness.
• a relationship Z10 or Z20 results from these surveys, which can be used to control the paper winding parameter, in this case the mean normalized layer thickness, using an influencing force.
• the individual Roll-up curves determined for different train sets are examples of the individual Roll-up curves determined for different train sets.
• the first approximation is a trend line that characterizes the decrease in the average layer thickness with increasing web tension, which corresponds to the observation that the winding hardness increases with increasing web tension.
• These trend lines are designated here with Z10 and Z20. The following relationship results:
• Y (F) means the average roll-up layer thickness for web tension F.
• the increase a x is negative. It should be noted that this functional relationship is independent of the diameter. For later use in a controller, the reverse relationship is required, which indicates the dependence of the web tension on the average roll-up layer thickness:
• these measuring points are fed to a neural network or another function approximator depending on the influence force and this is trained with the corresponding relationship.
• the neural network NN X learns by adapting its parameters w on the basis of this data and by means of known learning methods the relationship between force and average layer thickness or other paper winding parameter, based on the equation:
• a predictor in particular a neuronal predictor, can be defined which, based on the curve data of the reeling and unrolling, has a current diameter or another measurable one Characteristic d (n) predicts the value rewinding to diameter d (n + ⁇ ).
• the predictor can also use other / further characteristic data as input variables. That is, it predicts the current roll thickness as a paper winding parameter.
• x (n) as the roll layer thickness to the diameter d (n) and y (n) as the roll layer thickness
• z (n) as the state variable
• w (1 means the parameters of the neural network NN.
• the index ⁇ means an estimate, i the number of the station if several take-up stations are used and ⁇ a value correlated with time. Studies have shown that a simpler approximation is also possible lets use:
• y (i) (n + ⁇ ) w 1 (i) x (n) + w ⁇ i) y (i) (n) + 3 + z (i) (n + ⁇ ) (6)
• z (i) (n + ⁇ ) z (i) (n) + w ⁇ [y (i) (n) - y (i) (n)] (7)
• the parameters W j 1 'must be determined for the respective stations i. This is usually done by minimizing a cost function with the aid of a gradient method and the values from the measured roll-off and roll-up curves to the different throws, ie roll-up processes. These data are preferably sorted according to paper types and within the paper types according to the stations used. net.
• the special structure of the neural network enables a simplified, two-stage procedure.
• z (n) is set to 0 for all n and the parameters W j ... W 3 are calculated by solving the resulting (over-determined) multilinear system of equations. Known standard methods such as singular value decomposition can be used for this purpose.
• the parameter wj ' is now determined in such a way that the remaining residual error of the multilinear model is minimized.
• the individual predictions y (,) (n + ⁇ ) are preferably combined with the aid of a further neural network NN 3 to form a parameter if several paper winding stations are used in the reeling process.
• Each predictor represents a station-specific neuronal expert with regard to the roll thickness or another paper wrap parameter and an input variable for the controller is formed from the contributions of all experts In a winding process, not all stations are always active, or in extreme cases only one station is operated, only the contributions of the active stations are preferably taken into account.
• the prediction value y serves as an estimate of the roll-up value for the diameter d or another time-corrected variable.
• this is preferably processed during the control process. tet.
• time is used as the argument here and a time delay T t for the stages of the control loop concerned has been assumed to simplify the illustration.
• T t time delay
• the regulator R is intended to y from the setpoint, for example, a control difference and supplied to the estimate y (t).
• y for example, it is designed as a PID controller and uses the relationship between force and average layer thickness as the paper winding parameter that was determined at the input.
• a motor controller KS predetermined target force F should be corrected '(t). Accordingly, by varying the impact force F soll (t) or achieves the force controller KS at the individual winding stations Sl to Sll of the winding apparatus WV a desired winding layer thickness, a desired winding layer thickness profile during the winding process.
• measured values are recorded at the individual stations S1 to S11 for the winding and at the unwinding station of the reel AB and a layer thickness is determined from this as a function of a dead time T t , this dead time being necessary for determining or calculating the influencing variable from the measured variables is.
• predictors PI to Pll are provided, to which these specific influencing variables are supplied, and which predict a current layer thickness at the current time. That is, the dead time that elapses to determine the influencing variables from the measured variables is compensated for by the predictors.
• a combination unit KOM is used, which in a suitable manner superimposes the individual prediction results to an estimated value y (t).
• the force controller KS is in common paper winding devices already prior art and serves to keep constant the set force F so i ⁇ (fc) •
• In the proposed regulator R is a correcting force to the force F '(t).
• the controller uses the relationship from formula 3, which can be represented as follows:
• F MU (n) F, oU (n) + ⁇ F (n) (13)
• the web tension correction or the correction of the line force as an influencing force, compensates for the observed fluctuations in the roll-up curve, because the web tension increases with an increasing value of the roll-up layer thickness, and the web tension is reduced with a decreasing roll-up layer thickness compared to the nominal value. Because of the mechanical properties of the paper, i. H. Depending on the process, the web tension correction must not exceed or fall below certain values. For this reason, it is preferable to provide a limitation, for example by hard limits according to:
• a target paper winding parameter is thus determined by a predicted paper winding parameter corrected and in the controller R, which regulates the dependence of the influencing force on the paper winding parameter, a target correction force is generated which corresponds to the control difference from the predicted current paper winding parameter and target paper winding parameter.
• a corrected target force F soll (t) is specified in order to regulate the paper winding parameter at the individual winding stations or second paper windings Sl to Sll.
• more or fewer winding stations can also be provided on the winding device.
• predictors do not have to be provided for each winding device, but in some cases only the measured values of such winding stations can be recorded and predicted to an estimate which is known to be at the upper or lower end of the spread of the quality parameters of the winding process. That is, a particularly good or a particularly bad station is preferably selected.
• the influencing force is regulated in the same way for all winding stations.
• the influencing forces can be regulated separately for each winding station.
• the control arrangement from FIG. 5 can be used in such arrangements. It should be emphasized again that here the line force as well as the
• Web tension can be used to control the winding device.
• Figure 5 shows the control of the line force in a winding device.
• the web tensile force can also be regulated in a corresponding manner without restricting the invention, provided that the web tensile forces of individual winding stations F1 to F1 can be regulated separately.
• the representation in FIG. 5 differs from that in FIG. 6 only in that a line force L is entered instead of the web tensile force F and in that reel-specific regulators RI or KSI are provided. Analogous to the known mode of operation from FIG.
• this controller or this control arrangement regulates a predetermined nominal paper winding parameter by means of a correction force influencing the default force for the force controller KSI, which is derived from a predicted estimated value y (l) (t) to form the control difference , which is fed to the controller, was derived.
• the individual individual winding device is designated by WVI in FIG. 5. It is conceivable that in addition to the described regulation of the roll-up layer thickness as a paper roll influencing variable, a further improvement can be achieved by the web tensile force if the line force is also regulated, or in combination with the web tensile force.
• the nominal line force L ' is influenced and corrected by the controller RI and that the force control loop already present on the winding device, which regulates the influence force L ) (t), can be used without change, so that no change occurs existing paper winding devices is required. These are usually able to regulate a constant influence during the winding process.
• the dependence of the mean roll thickness as a paper roll influencing variable on the line force as an influencing force is first determined and approximated by a linear trend line, or the relationship is learned by a function approximator.
• the predictor PI is shaped on the basis of the known relationships between the processing of the reel and the winding of the paper wrap. That is, Measurements with different forces must also be carried out in advance and in an analogous manner to that for FIG
• Line force can be applied.

Landscapes

• Controlling Rewinding, Feeding, Winding, Or Abnormalities Of Webs (AREA)
• Paper (AREA)
• Handling Of Continuous Sheets Of Paper (AREA)
• Controlling Sheets Or Webs (AREA)
• Winding Of Webs (AREA)
• Replacement Of Web Rolls (AREA)

Applications Claiming Priority (3)

Publications (2)

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ID=7851444

Family Applications (1)

Country Status (11)

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Family Cites Families (13)

• 1997
  • 1997-12-10 DE DE19754878A patent/DE19754878A1/de not_active Withdrawn
• 1998
  • 1998-12-01 US US09/581,002 patent/US6363297B1/en not_active Expired - Fee Related
  • 1998-12-01 PT PT98965599T patent/PT1037842E/pt unknown
  • 1998-12-01 ES ES98965599T patent/ES2178304T3/es not_active Expired - Lifetime
  • 1998-12-01 WO PCT/DE1998/003531 patent/WO1999029604A1/fr active IP Right Grant
  • 1998-12-01 BR BR9813509-0A patent/BR9813509A/pt not_active Application Discontinuation
  • 1998-12-01 DK DK98965599T patent/DK1037842T3/da active
  • 1998-12-01 AT AT98965599T patent/ATE218493T1/de active
  • 1998-12-01 EP EP98965599A patent/EP1037842B1/fr not_active Expired - Lifetime
  • 1998-12-01 DE DE59804370T patent/DE59804370D1/de not_active Expired - Lifetime
  • 1998-12-01 CA CA002313461A patent/CA2313461A1/fr not_active Abandoned
• 2000
  • 2000-06-09 NO NO20002995A patent/NO317470B1/no not_active IP Right Cessation

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