JP2012240814A - Web winding device and method of controlling the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide refined winding characteristics of a winder in which output of a motor is restricted on the outermost peripheral side of a winding roll.SOLUTION: A nip load to a web by a nip roller is adjusted. In that case, in a winding range in which the winding ratio of the winding roll is ≥80%, the nip load is increased as the winding ratio increases. In a preferable embodiment, winding tension is optimized using an analysis model. In the analysis model, the nip load is set as a variable, and the nip load is optimized as well.

Description

  The present invention relates to a web winding device and a control method thereof.

  The web winding process is widely used in many industrial products such as liquid crystal displays, mobile phones and printed sheets. The present applicant has previously proposed the web winding technology of Patent Document 1. The winding technology includes a winding motor that rotates a winding core that winds the web, and tension adjusting means that adjusts the rotation speed of the winding motor to adjust the tension during winding. The winding range of the winding roll formed by winding is a predetermined winding ratio (the radius of the winding core is the initial value (0 percent), and the preset outermost radius of the winding roll is the maximum value) (The ratio of the radius of the winding roll at the present time as (100%)) is provided on the second half side so as to gradually reduce the winding tension of the web.

  On the other hand, the basic theory of web winding is evolving year by year. According to this basic theory, it becomes possible to quantitatively grasp the internal stress state of the winding roll on which the web is wound, using an analysis model including a predetermined nonlinear second-order ordinary differential equation. If the internal stress state of the winding roll can be modeled quantitatively, it is possible to optimize various conditions when winding the web. The present inventor calculates a technique for calculating the radial stress and the circumferential stress of the winding roll based on the previously proposed internal stress analysis model and calculating the optimal winding condition based on the calculation result. Developed and proposed (Non-Patent Document 1).

Japanese Patent No. 2825457

Hashimoto, et al., “Optimum Winding Tension and Nip-load into Wound Webs for Protecting Wrinkles and Slippage”, published by the Japan Society of Mechanical Engineers, Journal of Advanced Mechanical Design, Systems, and Manufacturing, Vol. 4 (2010) No. 1 pp.238-248

  According to the technique of Patent Document 1, practical winding characteristics can be obtained with relatively simple control such as setting a suitable taper rate (reduction rate of winding tension) in advance. On the other hand, as has been clarified by the technique of non-patent literature, the optimum winding control based on an elaborate analysis model is not necessarily a simple characteristic of lowering the tension on the second half side.

  Therefore, it has been desired to obtain a winding characteristic that approximates a more detailed analysis model.

  This invention is made | formed in view of the said subject, and makes it a subject to provide the web winding apparatus which can acquire the precise and practical winding characteristic based on the research result in recent years, and its control method.

  In order to solve the above-described problems, the present invention includes a winding motor that rotates a winding core that winds a web, and tension adjusting means that adjusts the tension during winding by adjusting the rotation speed of the winding motor. In the web winding device, a nip roller that presses the outer periphery of the web wound around the core, a nip load adjusting unit that adjusts a nip load applied to the web by the nip roller, and a winding ratio of the winding roll is 80. A web winding device comprising: a nip load control means for controlling the nip load adjusting means so as to increase the nip load as the winding ratio increases in a winding range of at least a percentage. is there. Here, the winding ratio means that the radius of the winding roll is the initial value (0 percent), the outermost peripheral radius of the winding roll set in advance is the maximum value (100 percent), and the radius of the winding roll at the present time Refers to the proportion of In this mode, in the winding range where the winding ratio of the winding roll is 80% or more, the nip load increases as the winding ratio increases, so the winding tension is insufficient that tends to occur on the latter half of the winding. The minute can be supplemented by the nip load. Therefore, more preferable winding characteristics are exhibited, and the internal stress of the winding roll is suitably distributed. As a result, generation of wrinkles and slack can be prevented as compared with the conventional case.

  In a preferred embodiment, tension function storage means for storing a tension function representing the winding tension with respect to the radial coordinate of the winding core, circumferential stress acting on at least the winding roll of the web, and frictional force between layers Objective function storage means for storing an objective function having a critical frictional force at which slip occurs as a parameter, a minimum value of radial stress inside the winding roll takes a positive value, and the frictional force is the critical friction. A constraint function storage unit that stores a constraint function that sets the constraint of the objective function to be greater than or equal to a force, and an evolution processing unit that evolves the tension function until the objective function becomes small under the conditions set by the constraint function The nip load control means controls the tension adjusting means based on the winding tension calculated by the evolved tension function, and the objective function is small. And it controls the nip load based on the value when it becomes Ku. In this aspect, since the tension function for setting the winding tension evolves under a predetermined condition and a suitable winding tension can be calculated, various webs are in a very suitable state while preventing wrinkles and slack. Can be rolled up.

  In a preferred aspect, the constraint function storage means stores a design variable having the nip load as a variable as a parameter of the constraint function, and the evolution processing means optimizes the nip load set as a variable. To do. In this aspect, in the process of evolving the tension function, optimization can be performed in consideration of the nip load used as an element of the design variable, so that the pressing force of the nip roller can be adjusted more suitably. Therefore, the winding tension can be optimized by a precise analysis model. In addition, in the winding range where the winding ratio of the winding roll is 80% or more, the nip load that increases as the winding ratio increases can be optimized while maintaining the optimal winding tension. Very favorable winding characteristics can be obtained.

  Another aspect of the present invention includes a winding motor that rotates a winding core that winds up a web, tension adjusting means that adjusts the tension at the time of winding by adjusting the rotation speed of the winding motor, and winding around the winding core. In a control method for controlling a web winding device including a nip roller that presses an outer periphery of a web to be taken, a winding ratio detection step for detecting a winding ratio of the winding roll, and the detected winding ratio And a nip load control step of controlling the nip load so as to increase the nip load as the winding ratio increases in a winding range of 80% or more. This is a control method.

  In a preferred embodiment, a tension function defining step for defining a tension function expressing the winding tension with respect to a radial coordinate of the winding core, circumferential stress acting on at least the winding roll of the web, and frictional force between layers, An objective function defining step for defining an objective function having a critical frictional force at which slip occurs as a parameter, a minimum value of radial stress inside the winding roll takes a positive value, and the frictional force is the critical friction A constraint function defining step that defines a constraint function that sets the constraint of the objective function to be greater than or equal to a force; and an evolution step that evolves the tension function until the objective function becomes small under the conditions set by the constraint function; The tension adjusting means is controlled based on the winding tension calculated by the evolved tension function, and the nip load when the objective function becomes small A control step for controlling the nip load of the winding device based on the nip load control step, wherein the nip load control step controls the tension adjusting means based on a winding tension calculated by an evolved tension function, and The nip load is controlled based on a value when the function becomes small.

  In a preferred embodiment, the constraint function defining step defines a design variable having the nip load as a variable as a parameter of the constraint function, and the evolution step optimizes the nip load set as a variable. Is.

  As described above, according to the present invention, the winding tension gradually decreases in the latter half of the winding range of the winding roll from the predetermined winding ratio. No take-up roll can be obtained. Moreover, in the winding range where the winding ratio of the winding roll is 80% or more, the nip load increases as the winding ratio increases, so the shortage of winding tension that tends to occur on the latter half of the winding is reduced. Can be supplemented by nip load. Therefore, more preferable winding characteristics are exhibited, and the internal stress of the winding roll is suitably distributed. As a result, the present invention has a remarkable effect that wrinkles and slack can be prevented from being generated as compared with the prior art.

It is a schematic structure figure of a winding device concerning one embodiment of the present invention. It is explanatory drawing which expands and shows the principal part of FIG. It is a graph which shows the characteristic for every dimensionless roll radius position of the winding tension in an evolution process. It is a graph which shows the characteristic for every dimensionless roll radius position of the nip load in an evolution process. FIG. 2 is an entity relationship (ER) diagram illustrating a portion of a database structure according to the embodiment of FIG. 1. It is a figure which shows an example of the screen for performing the optimization program which concerns on embodiment of FIG. It is a figure which shows an example of the screen for performing the setting program of the web which concerns on embodiment of FIG. 1, and a machine condition. It is a figure which shows an example of the screen for inputting the operating condition which concerns on embodiment of FIG. It is a figure which shows the state in execution of the optimization program which concerns on embodiment of FIG. 1 as an example. It is a flowchart which shows an example of the optimization control process which concerns on embodiment of FIG. It is a graph which shows winding tension-winding ratio. It is a figure which shows the characteristic calculated based on the winding tension | tensile_strength of FIG. 11, (A) is a graph which shows the frictional force for every winding ratio, (B) shows the radial direction stress for every winding ratio. Graph (C) is a graph showing the circumferential stress for each winding ratio. It is a graph which shows the example of execution of the optimization program which concerns on embodiment of FIG. It is a figure which shows the characteristic acquired based on the winding tension | tensile_strength and nip load of FIG. 13, (A) is a graph which shows the frictional force for every winding ratio, (B) is a radial direction for every winding ratio. The graph which shows stress, (C) is a graph which shows the circumferential direction stress for every winding ratio. It is a graph which shows another execution example of the optimization program which concerns on embodiment of FIG. It is a graph which shows the comparative example using the optimization program which concerns on embodiment of FIG. It is a graph which shows another comparative example using the optimization program which concerns on embodiment of FIG. It is a graph which shows another comparative example using the optimization program which concerns on embodiment of FIG. It is a graph which shows the example of a calculation of FIG. It is a graph which shows the example of a calculation of FIG. It is a graph which shows the example of a calculation of FIG. It is a graph which shows the example of a calculation of FIG. It is a graph which shows the example of a calculation of FIG. It is a flowchart which shows another aspect of this invention.

  The best mode for carrying out the present invention will be described below with reference to the accompanying drawings.

  First, referring to FIG. 1, a winding device 100 shown in FIG. 1 starts from a roll 1 of an unwinding device 101 that winds a web 10 through a plurality of guide rollers 2, a pair of pinch rollers 3, and a nip roller 4. It is wound around the outer periphery of the winding core 5a of the winding roll 5. Although not shown in the figure, an edge position control device that prevents the displacement of the web 10 and a load cell that detects the winding tension of the web 10 are arranged on the path from the roll 1 to the winding roll 5. ing.

  The nip roller 4 is provided with a nip load adjusting device 6 as a nip load control means for adjusting the pressing force against the take-up roll 5. The nip load adjusting device 6 is embodied by an electropneumatic converter having a pressurized air source, an air cylinder, a regulator for adjusting the output of the air cylinder, and the like, and a nip formed between the nip roller 4 and the take-up roll 5. The nip load N of 45 can be adjusted.

  Further, a motor 7 is connected to the winding core 5 a of the winding roll 5, and the winding core 5 a itself rotates to take up the web 10.

  The web 10 can be a flexible sheet used for a liquid crystal panel, a display monitor, a mobile phone, a solar cell system, and other various products, or a printed matter.

  The winding device 100 includes a control unit 20 for controlling the nip load adjusting device 6 and the motor 7. The control unit 20 includes a storage unit 21, a control unit 22, a motor control unit 23, and a nip load adjustment unit 24 as logical modules. Further, a display unit 25 and an input / output unit 26 are connected to the control unit 20 so that an operator can perform necessary data processing at the input / output unit 26 while viewing the display on the display unit 25. ing.

  The storage unit 21 is a module that is embodied by a ROM, a RAM, an auxiliary storage device, or the like, and includes an area for storing a control program for controlling the entire winding device 100 and parameters.

  The control unit 22 includes a microprocessor, a storage device, and an input / output interface, reads a control program and data stored in the storage device, executes the control program, and configures the elements ( This is a module that controls the motor control unit 23, the nip load adjustment unit 24, the display unit 25, and the input / output unit 26).

  The motor control unit 23 is a module that controls the rotation speed of the motor 7 based on the calculation result of the control unit 22. In the present embodiment, the motor control unit 23 also serves as tension adjusting means for adjusting the winding tension Tw of the web 10 through control of the rotational speed of the motor 7.

The nip load adjustment unit 24 is a module that adjusts the pressing force by the nip load adjustment device 6 based on the calculation result of the control unit 22. In the present embodiment, the nip load adjusting unit 24 can detect the winding ratio Rr of the winding roll 5 based on the rotation speed of the motor 7 and the operation time. Here, the winding ratio Rr means that the radius rc of the winding core 5a is an initial value (0 percent) and the outermost radius r _max of the winding roll 5 that is set in advance is a maximum value (100 percent). The ratio of the radius r of the take-up roll 5 is said.

  The display unit 25 is a unit embodied by a liquid crystal display or other display devices.

  The input / output unit 26 is a unit embodied by an input / output device such as a pointing device such as a keyboard or a mouse or a card reader.

  Note that, depending on the mode in which the winding device 100 is implemented, the control unit 20 may have a communication function to communicate a control program and data with the host computer.

  Next, the control of the winding tension Tw and the nip load N executed by the control unit 22 in the present embodiment will be described.

  First, main naming symbols (Nomenclature) used in the following description are shown in Table 1, and main physical quantities corresponding to FIG. 2 are shown.

Referring to FIG. 2, an interlayer pressure (radial compressive stress) σ _r always acts on the web 10 at an arbitrary winding radius r of the winding roll 5. At the same time, the pressure from each layer of the web 10 at the outer diameter is received. On the other hand, a circumferential stress σ _t acts in the circumferential direction, but depending on the radial position of the take-up roll 5, this can be either tensile or compressive. The stress in the width direction of the winding roll 5 is calculated assuming that it is normally uniform. Such a stress state can be obtained by calculation by applying a web winding theory (Hakiel model) described later.

  When the nip roll 4 is used, a nip load N [N] is generated in the nip 45 generated between the nip roll 4 and the take-up roll 5. As will be described in detail later, the nip load N also greatly affects the internal stress of the winding roll 5. Note that the nip load N is preferably calculated by a nip line load obtained by dividing the nip load by the web width. In the apparatus according to the present embodiment, a specific calculation is calculated by the nip line load. For the sake of convenience, all nip loads N will be unified.

  The winding device 100 according to this embodiment shown in FIGS. 1 and 2 is called a center drive winding method. It has been confirmed that the web winding theory called the Hakiel model is effective in analyzing the internal stress in such a center drive winding system. However, the Hakiel model does not consider air entrainment or nip load, and cannot be used as it is. Therefore, in the following description, in order to deepen the understanding of the present embodiment, an expanded Hakiel model is used when air entrainment and a nip load are involved. The outline of the Hakiel model is shown below.

The radial stress σ _ri in the i-th layer of the winding roll 5 is obtained by adding all the stress increments δσ _{ri in} each layer from the (i + 1) th layer to the n-th layer (final layer of winding). ). However, the i-th layer represents the i-th layer when the layer in the winding core 5a is the first and is counted in order toward the outer layer.

An equation governing δσ _{rij in} equation (1) (subscripts i and j are omitted in the following equation) is given as follows.

Since equation (2) is an equation that is the basis of winding, it is hereinafter also referred to as “winding equation”. The winding equation (2) contains the highest second order derivative with respect to the variable r, and the parameter (E _teq / E _req ) is a function of the nonlinear Young's modulus E _{req in} the r direction. Is a nonlinear second-order ordinary differential equation. Therefore, in order to solve the winding equation (2), two boundary conditions relating to the outermost layer (r = s) and the innermost layer of the winding roll 5 are required.

  Here, when the nip load is taken into consideration, each boundary condition is as follows.

Considering the entrainment of air by using the relationship between stress and strain of the equivalent layer of the initial web thickness t _f0 and the air film thickness h ₀ (t _f0 + h ₀ ), and Boyle's law The Young's moduli E _req and E _teq in the radial direction and the circumferential direction of Expression (3) can be obtained as follows.

However, the Young's modulus E _ra of the air layer is given as follows.

Furthermore, the winding process, the thickness h of any winding radius of the web thickness t _f and the air layer is respectively given as follows.

In Expressions (4) to (6), h ₀ and t _f0 indicate the thickness of the air layer and the web thickness at the initial stage of winding.

If air is caught during winding, slipping between the web layers of the winding roll 5 tends to occur. Therefore, for the purpose of reducing the amount of entrained air as much as possible and preventing slipping, a center drive winding method using the nip roller 4 is often employed as in the present embodiment. The thickness h ₀ of the air layer in that case can be evaluated by the line contact EHL theory (Elastohydrodynamic lubrication theory) between the winding roll 5 and the nip roll. In this embodiment, the following Hamrock and Dowson results (for details, see Hamrock, BJ, and Dowson, D., “Elastohydrodynamic Lubrication of Elliptical Contacts to Materials of Low Modulus I-Fully Flooded conjunction,” ASME J. Lubrication. Technology, Vol. 100, 1978, pp. 236-245).

Based on the equivalent internal stress of the winding roll 5, the circumferential stress σ _t is given by the following equation using the radial stress σ _r obtained from the equations (1) to (7).

  The above is the web winding theory based on the Hakiel model. At present, the formulation and verification of the tension equation (2) have been confirmed by a predetermined numerical analysis. As a result of such verification, it has also been confirmed that the winding tension Tw is a parameter that has a great influence when optimizing the roll internal stress, which is the main cause of the roll defect. On the other hand, the method for optimizing the winding tension Tw has not been sufficiently verified so far, and the method for optimizing the nip load N has not been studied so far. Therefore, in this embodiment, the winding tension Tw is optimized, and the nip load N is also optimized in the process, thereby providing a method for suitably eliminating any of various winding defects in a trade-off relationship. .

First, the storage unit 21 shown in FIG. 1 includes a tension function Tw (r), a nip load function N (r), an objective function f (X), a constraint function g _i (X) (i = 2n + 2m + 2) described below. ) Is stored. The tension function Tw (r) calculates the winding tension Tw with respect to the winding radius r. The nip load function N (r) calculates the nip load N with respect to the winding radius r. In order to evolve (optimize) the tension function Tw (r) and the nip load function N (r) in Expression (10), in this embodiment, the average value of the circumferential stress σ _{t is used} as an objective function, and generally a star Nipple load is applied in the process of optimizing the tension and minimizing the objective function by giving conditions to properly eliminate all defects such as defects, plastic deformation, and telescoping. N is also optimized.

  The tension function Tw (r) and the nip load function N (r) according to the present embodiment take the winding tension Tw into the winding roll 5 as shown below in consideration of the flexibility and ease of handling of the function. This is expressed by a cubic spline function with respect to the taking radius r and stored in the storage unit 21.

As is clear from equations (9) and (10), in this embodiment, the winding roll is divided into n equal sections from the winding start point to the outermost periphery, and the winding tension Tw of each section is determined by the spline method. The nip load N is interpolated. By setting M _i in Expression (9) and Expression (10) as a condition, the winding tension Tw and the nip load N are expressed as a function of smoothly connecting each section. The tension function Tw (r) in Expression (9) and the nip load function N (r) in Expression (10) are optimized (evolved) by setting an objective function and a constraint function. That is, Formula (9) and Formula (10) are evolved so that the minimum value of the circumferential stress in the winding roll 5 is non-negative and the average value of the circumferential stress is zero as much as possible. The take-up tension Tw and the nip load N can be obtained.

Referring to FIG. 3, as a method of evolving the tension function Tw (r) of Expression (9), the previous stage (k step indicated by the solid line) in the evolution process ((k + 1) step) indicated by the broken line in FIG. For each of the tension functions, the r coordinate of each contact P ^(k) (r _i , T _i ) is fixed, and the T _w coordinate is changed in the positive or negative direction by δT _i to create a new contact P ^{(k + 1). )} (R _i , T _i + δT _i ) is obtained. Using the new coordinate values obtained in this way, the function form is updated by equation (9), and it is successively evolved until the value of the objective function f (X) becomes optimum.

Also for the nip load function N (r) in equation (10), as shown in FIG. 4, the previous stage (indicated by the solid line) in the evolution process (step (k + 1)) indicated by the broken line in the same manner as in FIG. For the nip load function of k step), the r coordinate of each contact P ^(k) (r _i , N _i ) is fixed, and the N coordinate is changed by δN _i in the positive direction or the negative direction. A contact point P ^{(k + 1)} (r _i , N _i + δN _i ) is obtained. Using the new coordinate values obtained in this way, the function form is updated according to the equation (10), and it is successively evolved until the value of the objective function f (X) becomes optimum.

  Next, the variable of the objective function f (X) will be described.

  In the present embodiment, the design variable vector of the objective function f (X) is defined as follows and stored in the storage unit 21.

  In this embodiment, as is clear from the equation (11), the nip load is handled as a variable. By adding the variable of the nip load N to this design variable vector, the nip load N is optimized in the process of evolving the tension function Tw (r) of the equation (9) and the nip load function N (r) of the equation (10). It becomes possible to do.

  The objective function f (X) stored in the storage unit 21 is defined as follows.

In the present embodiment, the critical friction force F _cr is determined by experiments, and is 5 kN, for example. This critical frictional force F _cr is also a critical value for determining whether or not axial _deformation called telescope occurs, and is also referred to as “telescope condition value” as will be described later. Further, the frictional force F _i and the reference values σ _{t, ref} are respectively defined as follows.

On the other hand, the maximum and minimum values of the design variable ΔT _i and the nip load N, the minimum value of the circumferential stress σ _tmin , and the constraints that impose the average frictional force F _i between the web layers are defined as follows: 21 is stored.

In the equation (14), the constraint function g _i (X) (i = 1 to 2n + 2m + 2) is defined as follows and stored in the storage unit 21.

  In summary, the optimization of the winding tension Tw is expressed as follows.

  Next, in order to realize the optimization process described above, the storage unit 21 stores tables 211 to 221 relating to information for calculating the prediction theory model described above. Here, the table refers to a set of data expressed in a two-dimensional matrix (rows and columns) in the database system.

  Hereinafter, the table according to the present embodiment will be described with reference to FIG. In the following description, a table item is referred to as a “column”, and an actual value of the table (actual value assigned to the column) is referred to as a “row”. In FIG. 5, (PK) represents a primary key and (FK) represents a foreign key. The primary key is a column that uniquely identifies a row in the table. The foreign key has the same value as the primary key, and is used to refer to data in the table having the primary key. When a plurality of columns are represented as a set, they are enclosed in {}. Furthermore, the arrows in the figure indicate the relationship (relationship) between the tables, and indicate that the foreign key in the table on the end point side of the arrow refers to the primary key in the table on the start point side of the arrow. ing. Also, between the two tables, the correspondence between the primary key and the foreign key is represented by cardinality (number of rows), and the arrows indicate that the starting point is 0 or 1, and the end point has many cardinalities. Note that the illustrated table is a logical entity, and physically, the same data group may be composed of a plurality of tables, or the plurality of data groups may be composed of the same table. Good. In addition, the columns set in each table merely list those important for explaining the present embodiment in the table, and may have columns other than the illustrated items. . The table can be realized by text data, for example.

  Referring to FIG. 5, the auxiliary storage device of the storage unit 21 stores a web table 211, a winding core table 212, a nip roller table 214, a winding setting table 215, and an optimization technique table 216 as master tables. Yes.

The web table 211 is a table for registering the specifications of the web 10. For each web product number (primary key), the thickness h _f , width W, radial Young's modulus E _r , circumferential Young's modulus E _t , RMS Parameters including the synthetic roughness σ _ff , the static friction coefficient μs, the radial Poisson's ratio ν _tr , and the circumferential Poisson's ratio ν _rt can be registered.

The core table 212 registers the specifications of the core 5a. For each core number (primary key), the Young's modulus E _c , the core thickness t _c , the core radius r _c , and the Poisson's ratio ν Can be registered.

Nip roller table 214 is for registering the specifications of the nip roller 4, each nip roller part (primary key), to register the parameters including the radius r _n of the nip roller 4, the Young's modulus E _n, the Poisson's ratio [nu _n Can be done.

  The winding setting table 215 sets winding tension for each winding rate (provides an inversely proportional curve) using the winding setting code as a main key. For example, in the example to be described later, the winding tension Tw becomes a constant value (for example, 150 N) from the start of operation until the winding ratio is about 20% due to the settings registered in the winding setting table 215. After the percentage has elapsed, the product of the diameter of the winding roll 5 and the winding tension Tw can be set to be constant as the winding ratio increases.

  The optimization method table 216 defines setting conditions for giving specific conditions for performing arithmetic processing of the above-described equations (9) to (15) in the optimization processing described later. Using the method code as a main key, initial taper tension, winding tension, initial value of nip load, setting items for selecting whether or not to fix the final value, and the like are registered.

  Next, as a transaction table for operating the winding device 100, in this embodiment, a winding plan table 220, a winding plan detail table 221, a web product management table 222, an optimum winding table 223, and an optimum nip load table. 224 is provided.

  The winding plan table 220 stores specifications for managing the winding process plan, and registers items including the production date and order code for each winding plan code (primary key). Can be done.

The winding plan detail table 221 registers the specifications of the winding roll 5 produced in the winding plan and general specifications for processing for each winding plan code, and for each detail code for each winding plan. The part number of the nip roller 4 used, the part number of the winding core 5a, the part number of the web 10, the critical friction force F _cr (telescope condition value), the winding length, the number of turns n, the outermost roll radius r _out , the winding roll The number of 5 can be registered. Further, the winding plan detail table 221 includes foreign keys of the winding setting table 215 and the optimization method table 216. The winding plan can be set for each detail of the winding plan, and the optimization method. Can be set. Further, a column for setting initial values of initial taper tension and nip load in the set optimization method is provided.

  The web product management table 222 is for managing the production conditions of each specific product (winding roll 5) produced for each specification determined by the winding plan specification table 221. A composite key composed of an external key {production plan code, detail code} for associating with the detail table 221 and a production number is used as a main key, and the production date can be registered.

The optimum take-up table 223 sets specifications relating to the take-up tension Tw necessary for optimum take-up control, and takes up the take-up tension T _W and the take-up speed (motor rotation speed) V for each take-up plan specification. The dimensionless roll radius position r / r _c and the winding ratio Rr can be set. In the optimum winding table 223, the calculation result of the tension function Tw (r) of Expression (9) is registered by an optimization process described later.

The optimum nip load table 224 sets specifications regarding the nip load N necessary for optimum take-up control. The nip load N, take-up speed (motor rotation speed) V, and dimension roll are set for each take-up plan specification. The radial position r / r _c and the winding ratio Rr can be set. In the optimum nip load table 224, the calculation result of the nip load function N (r) of Expression (10) is registered by an optimization process described later. In the present embodiment, the optimum winding table 223 and the optimum nip load table 224 are associated with each other in a one-to-one relationship, and the winding tension Tw and the nip load N at an arbitrary winding ratio are related to each other. Be able to.

  By using the tables 211 to 221 as described above, various screens and view tables can be created, and the operator can realize the optimization calculation.

  With reference to FIG. 6, in this embodiment, a screen 300 for executing the optimization program is provided. This screen is a transition from the main menu (not shown).

  The screen 300 includes a command button 301 for setting web and machine conditions and a command button 303 for setting an optimization calculation method based on the set conditions. The setting result of the optimization calculation is displayed in a text box 304. In addition, the operation speed of the winding device 100 (the number of rotations of the motor 7) and the nip load N are displayed in text boxes 305 and 306, respectively. It is like that. By looking at the numerical values displayed in these text boxes, the operator determines whether correction is necessary. If the operator determines that correction is not necessary, the operator operates the transfer command button 307 to display the setting result. Instruct the control unit 20. The control unit 20 winds the web 10 based on the set result, processes it into the winding roll 5, and registers the transaction results in the tables 221 to 224 shown in FIG. In addition, a command button 308 is prepared on the screen 300 so that a transition to the main menu or the previous screen can be made as necessary.

  When the command button 301 in FIG. 6 is operated, the screen transitions to a screen 310 for setting web and machine conditions.

  With reference to FIG. 7, a screen 310 is provided with a combo box 311 for selecting the product number of the web 10 and a list window 312 for displaying the specifications of the web 10 selected in the combo box 311. From the combo box 311, web product numbers registered in the web table 211 of FIG. 5 are listed, and each specification relating to the selected product number is displayed in the list window 312. When it is necessary to register a new product number, it returns to the main menu and is registered from a registration screen (not shown).

  The screen 310 is provided with a combo box 313 for selecting the product number of the core 5a and a list window 314 for displaying the specifications of the core 5a selected in the combo box 313. From the combo box 313, the core number registered in the core table 212 of FIG. 5 is listed, and each specification related to the selected product number is displayed in the list window 314. When it is necessary to register a new product number, it returns to the main menu and is registered from a registration screen (not shown).

  In addition, the screen 310 is provided with a combo box 315 for selecting the product number of the nip roller 4 and a list window 316 for displaying the specifications of the nip roller 4 selected in the combo box 315. From the combo box 315, nip roller product numbers registered in the nip roller table 214 of FIG. 5 are listed, and each specification relating to the selected product number is displayed in the list window 316. When it is necessary to register a new product number, it returns to the main menu and is registered from a registration screen (not shown).

  The operator confirms the specifications displayed in the list windows 312, 314, and 316, and if there is no change in the displayed contents, the operator operates the command button 317 for execution and transitions to the next screen. When the command button 317 is operated, the screen changes to the operation condition input screen 320 of FIG.

With reference to FIG. 8, a combo box 318 for selecting an optimization method is prepared on the screen 320. The combo box 318 displays the optimization method code set in the optimization method table 216 of FIG. 5. By selecting this code, the setting condition in the optimization process can be selected. It has become. In addition, the screen 320 includes a text box 321 for setting the operating speed range and a text box 322 for inputting a telescope condition value (critical frictional force F _cr ). In the illustrated embodiment, a text box 323 that displays a predetermined conversion value by inputting an operation speed is prepared.

  Further, the screen 320 is provided with text boxes 324a and 324b for setting an upper limit value and a lower limit value of the winding tension, and text boxes 325a and 325b representing the converted values (nip line load) are upper limit values. , Provided corresponding to the lower limit value.

  Further, the screen 320 is provided with text boxes 326a and 326b for setting an upper limit value and a lower limit value of the nip load. The values in the text boxes 324a, 324b, 326a, 326b are registered in the winding plan details table 221. Further, the screen 320 is provided with a text box 326c for inputting an initial value of the nip load when the nip load is fixed according to the optimization method. The value input in this text box 326c is registered in the winding plan details table 221.

  The screen 320 is provided with an optimization execution button 327 for executing optimization processing based on the set conditions. The operator inputs the above-described specifications into a corresponding text box or the like, and clicks (operates) the optimization execution button 327, whereby the optimization process is executed based on the set condition. The screen 320 is provided with a display window 328 indicating that the optimization processing is being executed. A predetermined message “Calculating now. Elapsed time: 00:00:00” or the like is displayed on the display window 328. Is displayed. When the optimization process is completed, the screen transitions to a screen 330 showing the processing result.

Referring to FIG. 9, screen 330 displays text boxes 324 a, 324 b, 325 a, 325 b, 326 a and 326 b, buttons 327 and 308, and a graph display window 332 that are some items of screen 320. To do. In the window 332, a graph Tw _INV of the winding tension Tw based on the calculation result and a nip load N _INV are displayed.

  Next, the optimization process will be described with reference to FIG.

When the optimization execution button 327 displayed on the screen 320 in FIG. 8 is clicked, the control unit 20 reads necessary data from each table in FIG. 5 (step S101). Next, the control unit 20 initializes the counter variable k to 0 (step S103), and based on the read data, the basic equation (26), and the equations related to the basic equation (26), the tension function T _W ( for each r) and the nip load function N (r), optimized registered initial taper tension is calculated giving the method table 216, calculates a winding tension T _W and the nip load N in zone R0～rs ( Step S104). In the first step (k = 0), for example, a linear taper rate indicated by the phantom line in FIG. 3, the winding tension T _W is set, the characteristic indicated by the phantom line in FIG. 4, the nip load N Is set.

Next, the control unit 20 searches for the minimum value of the ^kth objective function f (X) ^(k) under the constraint of the constraint function gi (X) (step S105). Next, the control unit 20 calculates the tension function T _W (r) based on the winding tension T _W (ΔT _W1 , ΔT _W2 , ΔT _W3 ,... ΔT _Wn ) among the design variable vectors obtained at this stage. The nip load N (r) is evolved based on the nip load N (ΔL ₁ , ΔL ₂ , ΔL ₃ ,... ΔL _m ). Specifically, the r coordinate of each contact P ^(k) is fixed, and the _TW coordinate is changed in the positive or negative direction by ΔT _Wi to obtain a new contact P ^(k) . For example, when the initial winding tension T _W0 indicated by the phantom line has evolved, the tension function T _W (r) evolves to the winding tension T _Wk indicated by the solid line. The same calculation is performed for the nip load N (r ⁾ to obtain a new contact P ^(k) .

  Next, the control unit 20 verifies whether or not the searched objective function f (X) is a minimum value (step S107), and if not, increments step k (step S108) and step S6. The following is repeated, and if the minimum value is reached, the process proceeds to the control process.

Specifically, the winding tension T _W based on the tension function T _W (r) of Equation (9) evolved until the objective function f (X) reaches the minimum value, and the nip load function N ( r) to control the motor 7 (step S109). As a result, it is possible to obtain the take-up roll 5 that is free from star defects, plastic deformation, and telescopes either immediately after winding or after temperature change.

  Next, in order to clarify the operational effects of the present embodiment, some calculation examples will be described.

  First, the characteristics of the winding tension Tw obtained in the development process of the present invention will be described with reference to FIG.

When the nip load N is fixed at a predetermined value (N = 50 in the illustrated example) and the technique according to Patent Document 1 previously proposed by the present applicant is used, the characteristic is Tw _cov . In this specification, the winding tension Tw of the web 10 is gradually decreased from about 20% of the winding ratio Rr on the latter half side. When the operating condition of the motor 7 is set like the characteristic Tw _cov , the output is restricted like the output possible range M indicated by a virtual line.

  The output possible range M is calculated by the following procedure.

  That is, the rotational speed Nr [rpm] and the torque τ [N · m] of the winding core 5a are as follows.

  From these formulas (17) and (18), when the line speed is constant and the winding tension is constant, the rotational speed Nr and the torque τ of the motor change as the winding diameter increases.

  On the other hand, horsepower P [kw] is

  Equation (19 ') indicates that the output is constant regardless of the change in diameter under a constant speed and constant tension.

  Therefore, the necessary horsepower of the motor can be obtained from the equation (19 ′) as follows.

  Also,

  Then, since the horsepower is also P = ωτ, various modes can be calculated based on Expression (21).

  A calculation example is shown below.

On the other hand, when the optimization technique according to Non-Patent Document 1 previously proposed by the applicant is used and the nip load N is fixed at the same constant as the characteristic Tw _cov and the winding tension Tw is optimized, The identification is like Tw _opt . As is apparent from the figure, in the optimized characteristics, when the winding ratio Rr is 70% or more, the winding tension Tw is increased relatively abruptly. In such a characteristic, the friction force in FIG. 12 F, radial stress .sigma.r, circumferential stress sigma _t are both become excellent characteristics, collapse wound, it was found that the winding defects such as wrinkles can be suitably avoided .

However, when the operating characteristic of the motor 7 is conventionally set as Tw _cov , the motor output characteristic necessary for obtaining the optimum winding tension is obtained when the winding ratio Rr is 100%. It was also found that it was difficult to make the motor 7 follow the characteristic T w _opt because it was outside the output possible range M of 7.

Accordingly, the present inventors, in order to approach the operating characteristics of Tw _cov the operating characteristics of the same effect as the optimum characteristics Tw _opt, it was examined several comparative example shown in FIG. 11. In the comparative examples described below, the nip load N is the same constant (N = 50) as the characteristic T w _opt .

The first comparative example Tw _T1 is a case where the winding tension Tw after winding is increased to 130% with respect to the optimum characteristic Tw _opt .

The second comparative example Tw _T2 is a case where the winding tension Tw after winding is lowered to 80% with respect to the optimum characteristic Tw _opt .

The third comparative example Tw _T3 is a case where the winding tension is transiently increased when the winding ratio is about 50% with respect to the optimum characteristic Tw _opt .

Referring to FIG. 12, in the case of the first comparative example Tw _T1 , it was recognized that the frictional force F and the radial stress σr tend to be too high on the first half side of the winding ratio Rr.

In the case of the second comparative example Tw _T2 , it was recognized that the frictional force F and the radial stress σr tend to be too low on the first half side of the winding ratio Rr.

Further, in the case of the third comparative example Tw _T3 , the frictional force F and the radial stress σr tend to become excessively high at the timing when the winding tension Tw is increased.

In addition, in any of the comparative examples Tw _T1 to _T3 , the circumferential stress σ _t was not an appropriate value.

From these _facts , it has been found that it is difficult to simply obtain a characteristic that can replace the characteristic Tw _{cov with the} characteristic Tw _opt only by operating the winding tension Tw.

Further, in subsequent studies, it was also confirmed that an increase in the winding tension Tw on the latter half side of the winding ratio Rr in the characteristic T _opt is effective for avoiding a winding failure called a telescope. .

  From these findings, the present inventor treats the nip load N as a variable and optimizes the winding tension Tw and the nip load N at the same time as shown in the equation (11), thereby taking up the winding ratio of the winding tension Tw. The insufficiency of tension on the latter half of Rr was successfully compensated with the nip load N.

  As described above, according to the present embodiment, the motor 7 as the winding motor that rotates the winding core 5a that winds the web 10 and the rotational speed of the motor 7 are adjusted to adjust the tension during winding. A motor control unit 23 as tension adjusting means, and preferably the winding range of the winding roll 5 formed by winding the web 10 on the winding core 5a is from the predetermined winding ratio Rr in the latter half side. In the web winding device 100 set to reduce the winding tension Tw of the web 10, the nip roller 4 that presses the outer periphery of the web 10 wound around the winding core 5 a, and the nip load N applied to the web 10 by the nip roller 4. In the nip load adjusting device 6 as the nip load adjusting means for adjusting the nip load and the winding range where the winding ratio Rr is 80% or more, the nip load is increased as the winding ratio Rr increases. The web winding device 100 includes a nip load adjusting unit 24 as nip load control means for controlling the nip load adjusting device 6 so as to increase the weight N.

  According to the present embodiment, in step S109 of FIG. 10, in the winding ratio detection step of detecting the winding ratio Rr of the winding roll 5, and in the winding range where the detected winding ratio Rr is 80% or more. The nip load control step of controlling the nip load N so as to increase the nip load N as the winding ratio Rr increases is executed.

  For this reason, in this embodiment, since the winding tension Tw gradually decreases in the latter half of the winding ratio Rr of the winding roll 5 from a predetermined value, the winding does not have winding defects such as wrinkles or slack as usual. A take roll 5 can be obtained. In addition, in the winding range in which the winding ratio Rr of the winding roll 5 is 80% or more, the nip load N increases as the winding ratio Rr increases, so that the winding tension that tends to occur on the latter half side of the winding is increased. The shortage of Tw can be supplemented by the nip load N. Therefore, more preferable winding characteristics are exhibited, and the internal stress of the winding roll 5 is suitably distributed. As a result, generation of wrinkles and slack can be prevented as compared with the conventional case.

Further, in the present embodiment, a tension function storage unit that stores a tension function that expresses the winding tension Tw with respect to the radial coordinate of the winding core 5a, and a circumferential stress σr that acts on at least the winding roll 5 of the web 10; Objective function storage means for storing an objective function having the frictional force F between the layers and the critical frictional force _Fcr causing slipping as parameters, and the minimum value of the radial stress inside the winding roll 5 takes a positive value, In addition, a constraint function storage means for storing a constraint function for setting the constraint of the objective function so that the friction force F becomes equal to or greater than the critical friction force F _cr, and a tension function until the objective function becomes small under the conditions set by the constraint function The nip load adjusting unit 24 controls the motor control unit 23 based on the winding tension Tw calculated by the evolved tension function, and the objective function becomes smaller. And it controls the nip load N based on the value. For this reason, in this embodiment, the tension function for setting the winding tension Tw has evolved under a predetermined condition, and a suitable winding tension Tw can be calculated, so that various webs can be prevented while preventing wrinkles and slack. 10 can be wound up in a very favorable state.

  In the present embodiment, the constraint function storage means stores design variables having the nip load N as a variable as a parameter of the constraint function, and the evolution processing means optimizes the nip load N as a variable. It is. For this reason, in the present embodiment, optimization can be performed in consideration of the nip load N used as an element of the design variable, so that the pressing force of the nip roller 4 can be adjusted more suitably. Therefore, the winding tension Tw can be optimized by a precise analysis model. In addition, in the winding range where the winding ratio Rr of the winding roll 5 is 80% or more, the nip load N that increases as the winding ratio Rr increases is optimized while maintaining the optimal winding tension Tw. Therefore, a very favorable winding characteristic can be obtained.

  Therefore, according to the present embodiment, the winding roll 5 having no winding failure such as wrinkles or slack can be obtained as usual, while the winding ratio Rr of the winding roll 5 is 80% or more. In the range, since the nip load N increases as the winding ratio Rr increases, the shortage of the winding tension Tw that tends to occur on the latter half of the winding can be supplemented by the nip load N. Therefore, more preferable winding characteristics are exhibited, and the internal stress of the winding roll 5 is suitably distributed. As a result, it is possible to prevent the occurrence of wrinkles and slack, as compared with the conventional case.

Examples are shown below.
(First embodiment)
Referring to FIG. 13, in the first example, the initial values of the winding tension Tw and the nip load N are not fixed, and the optimization process is executed under freely adjustable conditions. In the first example, the characteristics of the winding tension Tw and the nip load N are as shown by Tw _INV and N _INV , respectively. As is apparent from FIG. 13, the winding tension Tw _INV greatly decreases until the winding ratio Rr reaches 20%, gradually decreases after 20%, and gradually increases at about 80%. ing. Even when the winding ratio Rr is 100%, the value is substantially the same as the characteristic _{T cov} in the technique according to Patent Document 1, and the gap SH is as close to 0 as possible. It was.

Referring to FIG. 14 (A), the frictional force F in the first embodiment is higher than the critical frictional force _Fcr over almost the entire winding ratio Rr, and has good frictional force characteristics. It was confirmed. Further, as shown in FIG. 14B, it was confirmed that a characteristic approximate to the characteristic T w _opt can be obtained over the entire region in the radial direction stress. Furthermore, as shown in FIG. 14C, it was confirmed that a value of 0 or more can be maintained over the entire region even in the circumferential stress.

As a result, it was confirmed that the optimum winding tension Tw can be obtained by the first embodiment even when the operation characteristics of the motor 7 are still set by the technique according to Patent Document 1.
(Second embodiment)
Referring to FIG. 15, in the second embodiment, the optimization process is executed with the initial values fixed in both the winding tension Tw and the nip load N. As a result, almost the same result as in FIG. 14 was obtained. As a result, even when the optimization processing is executed with both the initial values of the winding tension Tw and the nip load N fixed, the optimal winding is performed while setting the operating characteristics of the motor 7 using the technique according to Patent Document 1. It was confirmed that the take-up tension Tw can be obtained.
(First comparative example)
Referring to FIG. 16, in the first comparative example, the nip load N is fixed to a predetermined optimum value (N = 107 N / m in the illustrated comparative example), and only the winding tension Tw is optimized. did.

The result was as Tw _cp1 . In the first comparative example, when the winding ratio Rr was 100%, it was outside the output possible range M.
(Second comparative example)
Referring to FIG. 17, in the second comparative example, the initial value of the nip load N is fixed to take measures to prevent wrinkles at the initial winding stage, and the nip load N is set at a winding ratio of 25% or more. It fixed and the process which optimizes winding tension Tw was given.

The result was as shown in Tw _cp2 . Also in the second comparative example, when the winding ratio Rr is 100%, the output range M is outside the range.
(Third comparative example)
Referring to FIG. 18, in the third comparative example, the nip load N is fixed at an arbitrary value (N = 100) and only the winding tension Tw is optimized.

The result was as shown in Tw _cp3 . Also in the third comparative example, when the winding ratio Rr is 100%, the output range is outside the range.

  19 to 23 are graphs showing the internal stress of the winding roll 5 based on the characteristics of the first and second examples and the first to third comparative examples.

As is apparent from these figures, the friction force cases F, radial stress .sigma.r, the circumferential stress sigma _t, but both are suitable, in the first and second embodiments, the winding ratio whereas Rr can be kept low winding tension Tw _INV of at 100%, in the first to third comparative examples, winding tension Tw of at winding ratio Rr is 100% _{cp1 ~Tw cp3} Was confirmed to be high.

  The present invention is not limited to the embodiment described above.

  For example, optimal control can be achieved approximately using a program as shown in FIG.

  Referring to FIG. 24, in the modification shown in FIG. 24, the operating characteristics of motor 7 are set in control unit 20 based on the technique of Patent Document 1 (step S200). A preset winding ratio (preferably 80%) is set as a threshold value. The control unit 20 calculates the winding ratio (step S201), and determines whether or not the calculated winding ratio has reached a threshold value (step S202). If the winding ratio has reached the threshold value, the control unit 20 increases the nip load N at a predetermined ratio according to the winding amount (step S203). In that case, the winding tension Tw remains set in step S200. The control unit 20 determines whether or not the winding amount has been reached, that is, whether or not the winding ratio has reached 100 percent (step S204). If the winding amount has not been reached, the process proceeds to step S203. Then, the above-described processing is repeated, and when the winding amount is reached, the processing is terminated. If it is determined in step S202 that the winding ratio has not reached the threshold value, the winding tension is controlled based on the set value set in step S200 (step S205). The process described above is repeated.

  In the example shown in FIG. 24, the optimum value calculation is performed for each process by determining the threshold value in step 202 and the increase ratio of the nip load in step S203 in advance based on experiments and simulation calculation of the optimum value. Thus, it is possible to obtain an approximately optimum winding characteristic without executing the process.

  In addition, it goes without saying that various modifications are possible within the scope of the claims of the present invention.

4 Nip roller 5 Winding roll 5a Winding core 6 Nip load adjusting device 7 Motor 10 Web 20 Control unit 21 Storage unit 22 Control unit 23 Motor control unit 24 Nip load adjusting unit 25 Display unit 26 Input / output unit 45 Nip 100 Web winding device

Claims (6)

In a web winding device comprising a winding motor that rotates a winding core that winds a web, and tension adjusting means that adjusts the tension at the time of winding by adjusting the rotational speed of the winding motor,
A nip roller for pressing the outer periphery of the web wound around the winding core;
Nip load adjusting means for adjusting the nip load on the web by the nip roller;
Nip load control means for controlling the nip load adjusting means so as to increase the nip load as the winding ratio increases in a winding range where the winding ratio of the winding roll is 80% or more. A web winding device. The web winding device according to claim 1, wherein
Tension function storage means for storing a tension function representing the winding tension with respect to the radial coordinate of the core;
Objective function storage means for storing an objective function having at least parameters of circumferential stress acting on the web winding roll, interlayer frictional force, and critical frictional force causing slipping;
Constraint function storage means for storing a constraint function for setting the constraint of the objective function so that the minimum value of the radial stress inside the winding roll takes a positive value and the friction force is equal to or greater than the critical friction force When,
Evolution processing means for evolving the tension function until the objective function becomes smaller under the conditions set by the constraint function,
The nip load control means controls the tension adjusting means based on a winding tension calculated by an evolved tension function, and controls the nip load based on a value when the objective function becomes small. A web winder characterized by being. In the web winding device according to claim 2,
The constraint function storage means stores a design variable having the nip load as a variable as a parameter of the constraint function,
The evolution processing means optimizes the nip load set as a variable. A winding motor that rotates a winding core that winds the web, a tension adjusting means that adjusts the tension during winding by adjusting the rotation speed of the winding motor, and presses the outer periphery of the web that is wound around the winding core. In a control method for controlling a web winding device provided with a nip roller,
A winding ratio detecting step for detecting a winding ratio of the winding roll;
A nip load control step for controlling the nip load so as to increase the nip load as the winding ratio increases in a winding range in which the detected winding ratio is 80% or more. A method for controlling a web winding device. In the control method of the web winding device according to claim 4,
A tension function defining step for defining a tension function representing the winding tension with respect to the radial coordinate of the core;
An objective function defining step for defining an objective function with parameters of at least circumferential stress acting on the web winding roll, frictional force between layers, and critical frictional force causing slip;
A constraint function definition step for defining a constraint function for setting a constraint of the objective function so that the minimum value of the radial stress inside the winding roll takes a positive value and the friction force is equal to or greater than the critical friction force When,
An evolution step of evolving the tension function until the objective function is reduced under conditions set by the constraint function;
A control step of controlling the tension adjusting means based on a winding tension calculated by an evolved tension function, and controlling the nip load of the winding device based on a nip load when the objective function becomes small; With
The nip load control step controls the tension adjusting means based on a winding tension calculated by an evolved tension function, and controls the nip load based on a value when the objective function becomes small. A method for controlling a web winding device. In the control method of the web winding device according to claim 5,
The constraint function definition step defines a design variable having the nip load as a variable as a parameter of the constraint function,
The evolution step is for optimizing the nip load set as a variable.

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