JPH06149305A - Position controller for film coater device - Google Patents

Abstract

PURPOSE:To ensure the optimum position control of a gap formed between a web and a coater by applying plural control rules stored previously in a memory to the coater position control in the order of higher priority after reception of the output of a gap measuring means. CONSTITUTION:A control part 11 calculates the maximum value, the minimum value, and the mean value of the gap formed between a web 3 and coater 4 based on the output of a gap measuring means 10 that is measured by many times within a fixed time. Then it is decided whether these calculated values exceed or not each level set on a control value table 12. Then the position control of the coater 4 is decided. Meanwhile plural control rules can be set in a table form. When plural control rules are set up at a time, the rules of higher priority are used for the position control of the coater 4. Then the set-up of a rule is decided when a logical expression is satisfied for the relation set among the maximum value, the minimum value, and the mean value of each output of plural means 10 which are ground in the width direction of the coater 4.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a position control device for a film coating device, and more particularly to a film coating device capable of optimally adjusting a gap between a web and a coater for film coating. The present invention relates to a device position control device.

[0002]

2. Description of the Related Art When manufacturing a photographic light-sensitive material, a coating solution is applied to one side of a film base called a web, and after gelling, the coating solution is applied to the opposite side. There is a method and an apparatus for applying the coating liquid to the opposite surface by continuously running the powder on a roll while supporting it in a gas-free manner. The photographic light-sensitive material coated on both sides of such a web is commercially available as a print light-sensitive material, an X-ray film, a color film and the like.

FIG. 4 is a conceptual diagram of a film coating apparatus for coating a coating liquid on both sides of a web. In the figure, the web 3 of the original winding is obtained by sequentially winding several hundreds to thousands of meters around a core and feeding it out from the outside. When the unwinding of one original winding is finished, the running of the web in the coating step is stopped. Without connecting, the next original roll is continuously supplied with a plurality of original rolls at a constant speed.

In the coating step, the web 3 first comes into direct contact with the roll 2 and the coating device (coater) 1 is used to coat a film on one surface by a conventionally known method. The coating film applied to the web 3 passes through the cold air zone 6. In the cold air zone 6, cold air is applied to the coating film by the slit plate or the group of small holes 7, and in order to further improve the cooling efficiency, a cooling roll group installed with a gap of 2 to 3 mm on the uncoated surface of the web 3. 8 are brought into contact with each other and air is sucked from the roll side to increase the contact area with the cooling roll group 8 to gel the coating film.

Next, the web 3 having the gelled coating film is coated by the coating device 4 on the opposite surface of the roll 5 of the coating device at the non-contact supporting portion. In this non-contact supporting portion, gas is ejected from the curved surface of the roll having a large number of gas ejection holes on the surface of the gelled coating film to support the web 3 in a non-contact state. The roll 5 is called an air roll.

FIG. 5 is an enlarged sectional view of the coating section. The position of the tip of the coater 4 is the application portion of the application liquid. The distance from the tip of the coater to the web 3 is called a gap, and its width is represented by w. The width w of this gap is several tens of μm to several hundreds of μm. Reference numeral 5 is the air roll described above. There is a hole in the surface for passing air, and air of a predetermined pressure is blown out. Web 3
Is held by a fluid such as air without contacting the solid matter.

In the production of photographic light-sensitive materials, the thickness of the applied film must be kept within 1%.
For that purpose, it is necessary to keep the gap w between the tip of the coater 4 and the surface of the web 3 to be coated in a constant range as much as possible.

In such position control, conventionally, position control is performed with a control amount according to the degree (deviation) of the process value from the target value. Alternatively, the control is turned on and off by detecting that the allowable value has been exceeded.At this time, the dynamic characteristics of the process and the optimum control cycle are generally obtained, and the deviation between the process value and the target value within the control cycle is used. Take control.

For example, in the case of PID control, the control amount is determined by multiplying the rate of change of data within the control cycle, the integrated value of the deviation, and the deviation by a coefficient according to the dynamic characteristics of the process. There is. However, it is difficult to obtain an appropriate control coefficient unless the dynamic characteristic of the controlled object is constant or predictable.

[0010]

In order to coat on the air roll 5, the gap w between the coater 4 and the web 3 changes every moment, so position control is performed so as to adjust the gap within a certain range. There is a need. However, Web 3
Includes a position change of a wide frequency, and the cycle and width of the gap change gradually depending on the position of the web 3 to be applied in the width direction and the longitudinal direction.

In the prior art such as PID control, in order to control the position of the coater 4 according to the movement of the web 3 having such a behavior, the control coefficient depends on the change of the dynamic characteristic of the position change of the web 3. An appropriate control amount could not be obtained unless the control was performed by changing the above. In addition, it is difficult to predict this change in dynamic characteristics.

Since it is difficult to properly control the gap w between the web to be coated and the coater by the conventional position control system, there is a control system capable of dynamically responding to the behavior of the position change of the web. Was needed.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a position controller for a film coating apparatus capable of optimally controlling the position of the gap between the web and the coater. I am trying.

[0014]

According to the present invention for solving the above-mentioned problems, the position of a film-coating coater, which is arranged in close proximity to and is opposed to a gas-supported web, is set so that the gap falls within a certain range. In a position control device for a film coating device for controlling, a gap means for measuring the gap at a plurality of positions in the width direction of the web is provided, and a plurality of gaps provided in advance in the memory upon receiving the output of the gap measuring means It is characterized in that the control rules are adopted in order of coater position control in descending order of priority.

[0015]

A means for measuring the gap between the coater and the web at a plurality of positions in the width direction of the gas-supported web is provided, and the control unit is provided with a plurality of control value tables in a control value table preset on the memory in a table format. The output of the gap measuring means is determined in accordance with the control rule of 1 to determine whether the condition is satisfied. Then, when the condition is satisfied, the control amount is selected from the control rule having the highest priority and the control is performed. With such a configuration, it is possible to optimally control the position of the gap between the web and the coater in both the width and the length.

[0016]

Embodiments of the present invention will now be described in detail with reference to the drawings. FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention. The same parts as those in FIG. 4 are designated by the same reference numerals. In the figure, 3 is a web, 4 is a coater (coating device) for coating a film on the web 3, and 5 is an air roll for supporting the web 3 in a non-contact manner by gas.

Reference numeral 10 is a plurality of gap measuring means arranged in the width direction of the web 3, and 11 is a control portion for receiving the outputs of these gap measuring means and controlling the positions of the web 3 and the coater 4. A computer system, for example, is used as the control unit 11. A control value table 12 stores a plurality of control rules and is provided in the memory.
Reference numeral 13 denotes a coater drive unit that moves the position of the coater 4 according to a control signal from the control unit 11. The operation of the apparatus configured as described above will be described below.

First, the contents of the control value table 12 and the control operation of the control section 11 will be described. The determination of the condition in the control unit 11 is as follows. The control unit 11 calculates the maximum value, the minimum value, and the average value of the gap w between the web 3 and the coater 4 from the output of the gap measuring unit 10 measured many times within a fixed time (one control cycle). Then, it is determined whether or not those values exceed the values set in the control value table 12, and it is determined whether or not the position control of the coater 4 is performed.

Further, for the determination of the satisfaction of the condition, a determination method for counting the number of the gap measuring means 10 out of the allowable range and determining whether or not the control for adjusting the gap is performed is added.

FIG. 2 is a diagram showing an example of the set values of the control rules stored in the control value table 12. Four control rules are shown for each of the case of one cycle and the case of M cycles. In the figure, (1) to (4) are control rules of one cycle, and (5) to (8) are control rules of M cycle. And the priority is (1)>(2)> (3)
>(4)>(5)>(6)>(7)> (8).

As shown in the figure, the control rules are set in a table format so that a plurality of rules can be set. When a plurality of rules are satisfied at the same time, the rule with the higher priority is used to determine the position. Take control.

Among these control rules, one of the control rules is the maximum value Gn of each output of the gap measuring means 10 installed in plural numbers (n pieces) in the width direction of the coater 4.
It is assumed that one rule is established when the respective logical expressions of the magnitude relationship with the values set for MAX, the minimum value GnMIN, and the average value GAVE are established.

Further, in the control rule, the number of times that the logical expression is satisfied is counted, and when the value exceeds the value set in the table, a judgment expression called CNT that is satisfied is also prepared. ing. The upper table, which is displayed as one cycle, determines whether the rule is satisfied and determines whether or not the control is performed in one data collection cycle. In the lower table displayed as M cycles, when CNT is set in the logic, the number of data for which the formula of the row in which CNT is set in M cycles is satisfied is counted, and the number in M cycles is counted. When the cumulative total of the counts reaches the count reference value (here, 5) shown at the bottom of the table, that rule is established and control is performed.

Next, the mechanism of condition judgment in each rule will be described below. (Condition Judgment of Rule for One Cycle) (a) The judgment condition of the conditional expression (three expressions) in each rule is
If it is AND, when all the corresponding data (output of the gap measuring means 10) satisfy the condition, if it is OR, it is considered that the condition for each row is satisfied when even one corresponding data satisfies the condition. (B) When all the conditional expressions described in GnMAX, GnMIN, and GAVE are satisfied, it is considered that rule (n) is established. (C) A line for which a conditional expression is not described in the GnMAX, GnMIN, and GAVE lines is unconditionally satisfied for that line. However, if there is no description on all three lines, the condition is not satisfied. (Condition Judgment of Rule of M Cycle) (a) Judgment of Condition by Result of Establishment up to Maximum M Cycles / Number of CNTs. (B) When other rules are established, the result of establishment of M cycles / C
The NT number is reset. (C) The judgment condition of the conditional expression (three expressions) in the rule is A
If it is ND, OR when all applicable data satisfy the condition
Then, if even one corresponding data satisfies the condition C
If it is NT, it is considered that the condition on a line-by-line basis is satisfied when even one corresponding data item satisfies the condition. In addition, CN
In the case of the T condition, the number of data satisfying the condition for each expression is used as the count value. When the CNT condition is not in the rule, the count value is 1. (D) GnMAX, GnMIN, and GAVE lines that have no conditional expression are unconditionally satisfied. However, if there is no description on all three lines, the condition is not satisfied. (E) The sum of the count numbers for the M cycles of the rule (n) is calculated, and if (sum) ≧ (count reference value set in the control value table), it is considered that the rule (n) is satisfied.

Next, the contents of each rule (1) to (8) will be described. ○ Rule (1): When the maximum value GnMAX exceeds 450μ at any one place and the minimum value GnMIN is less than 140μ even at one place, the fluctuation of the gap w is too large to control, and therefore the gap is changed. I don't. The control value +0 in the table indicates that control is not performed (the same applies hereinafter). ○ Rule (2): When the maximum value GnMAX exceeds 100μ even at one place and the minimum value falls below 10μ even at one place, the fluctuation of the gap w is too large to control.
Therefore, the gap is not changed. Rule (3): If the minimum value GnMIN is less than 120 μ even at one place, the gap w is small and the uniformity of the coating film may be impaired. Therefore, the coater 4 is retracted by 30 μ to widen the gap w. The control value +30 is the gap w of 30
Indicates that μ is widened. The fact that the logical expression of GnMAX in rule (3) is shown as 0 () indicates that it does not matter how the value of GnMAX is (the same applies hereinafter). Rule (4): When the minimum value GnMIN exceeds 250 μm, the gap w is large and the uniformity of the coating film may be impaired. Therefore, the coater 4 is advanced by 50 μm to narrow the gap w. "AN" in logical expression> 250 (AND)
D ″ means all gap measuring means 10. Rule (5); 130 even if the minimum value GnMIN is one place.
If it is less than μ, the count value in this cycle is set to 1, and the sum of the count values in the past M cycles is calculated. When the sum of the count values reaches 5, the gap w tends to be small, so the coater 4 is retracted by 20 μ to widen the gap w. However, when the control is performed according to any one of the rules (1) to (8), the count value of this M cycle is reset to 0. ○ Rule (6); The minimum value GnMIN is 300 even in one place.
When μ is exceeded, the count value in this cycle is set to 1, and the sum of the count values in the past M cycles is calculated. When the sum of the count values reaches 5, the gap w tends to be large, so the coater 4 is advanced by 20 μ to narrow the gap w. Rule (7): When the average value GnAVE of the gap w obtained from the gap measuring means 10 in the width direction exceeds 210 μ, the count value in this cycle is set to 1 and the sum of the count values in the past M cycles is calculated. When the sum of the count values reaches 5,
Since the gap w tends to be large, the coater 4 is retracted by 10 μ to narrow the gap w. Rule (8): The number of gap measuring means 10 whose minimum value GnMIN exceeds 280μ is counted, and the counted value is set to k. When the sum of the count values of the past M cycles reaches 5, the gap w tends to be large, so the coater is set to 1
The gap w is narrowed by advancing by 0 μ.

In the above rules, the gap measuring means 10
The control unit 11 determines whether or not the logical expression is satisfied by receiving the output of the above. The control unit 11 also outputs a signal (control value) for position control of the coater 4 when the logical expression is satisfied to the coater driving unit 13. The coater driving unit 13 moves (forwards or backwards) the coater 4 based on the control value signal from the control unit 11, and adjusts the gap w between the web 3 and the coater 4.

In setting the position control rule, the control for avoiding the gap leading to coating failure is 1
The control that is performed on the data of the control cycle and that controls the vibration width of the gap within a safer and desirable range is performed while viewing the data of one control cycle or more (for example, M cycle). By selecting such a control method, it is possible to perform position control that takes advantage of each control method.

Next, the operation of the device of the present invention will be specifically described with reference to FIG. The web 3 is running on the air roll 5, and coating is performed by the coater 4 on the air roll 5 in the width direction perpendicular to the running direction of the web 3. Air roll 5
Five gap measuring means (sensors) 10 for measuring the gap w between the web 3 and the tip of the coater 4 are installed therein.

The distance between the web 3 and the tip of the coater 4 constantly fluctuates due to the flow of air, the fluctuation of the tension of the web, the flatness of the web 3, and the like. Further, the variation of the gap w also differs depending on the location of the coater 4 in the width direction, and the behavior is not constant even at the same location. However, the coater 4 is a device that applies a constant flow rate of the coating liquid onto a smooth slope to apply the coating liquid to the web 3. If the gap between the tip of the coater 4 and the web 3 is within a certain fixed range, the coater 4 may be slightly wide or long. Even if there is a variation in, the flow rate of the coating liquid is constant, so that a coating film having a uniform thickness can be obtained. The coater 4 is a known device used in industries such as photosensitive material manufacturing.

In this system, the gap between the coater 4 and the web 3 is adjusted according to the movement of the web 3, and the coater position is adjusted by a plurality of predetermined rules as described above.

The rules in the control value table 12 are set as shown in FIG. In the line of the conditional expression, only 0 is shown without an inequality sign, which means that the conditional expression is not judged when the conditional expression is not set.
The rule expresses the magnitude relation with respect to GnMAX, GnMIN, and GAVE in the direction of the inequality sign, and the value (GnMAX, GnM corresponding to each of the sensors 10 is shown.
A logical condition can be set such that all of (IN) are (AND), and even if only one (OR) satisfies the conditional expression.

Since GAVE is the average value of all the data of the sensor 10, it can be set only for the determination of the magnitude relationship. Further, in the lower table, the condition CNT for accumulating the number of outputs of the sensor 10 for which the inequality sign holds in M cycles is also set. One rule is composed of a combination of conditional expressions (logical expressions) shown in three lines.

In this case, the M period is 5 periods as shown in the lower part of FIG. 2, and the length of 1 period is 10 seconds. Since the sensor 10 installed in the air roll 5 continuously measures the gap between the web 3 and the coater 4, the control unit 1
The control unit 11 samples a large number of data for each cycle set by 1, and the maximum values G1MAX to G5MAX and the minimum value G1MIN of the data are sampled for each of the five sensors 10.
At the same time as obtaining G5MIN, the average value GAVE of all data of the five sensors 10 is also obtained.

Next, a concrete example will be described. Here, an example in which the CNT condition of the M cycle rule is included (rule (8)) will be described. The conditional expression is GnMIN> 2
Since it is only 80 (CNT), the formulas in the other rows are unconditionally satisfied. FIG. 3 shows a condition until the condition is satisfied by adding a mark (◯) to the position of the gap measurement (sensor position) where this conditional expression is satisfied. In this figure, three examples from Example 1 to Example 3 are shown. (Example 1) In this case, all the measured values of the sensor 10 exceeded 280 μ in the first cycle. Therefore, CNT
The count value of becomes 5, and the sum becomes 5, and the rule is established. (Example 2) In this case, only the sensor 3 exceeds 280μ from the first cycle to the fifth cycle. Therefore, the CNT value of each cycle becomes 1, and the sum of them becomes 5 in the 5th cycle.
And the rule holds. (Example 3) In this case, only the sensor 3 is 28 in the first cycle.
0 μ is exceeded, the sensors 2 and 4 exceed 280 μ in the second cycle, the sensor 3 again exceeds 280 μ in the third cycle, and the sensors 2 and 4 again exceed 280 μ in the fourth cycle. Therefore, the CNT value in each cycle is 1, 2, 1, 2.
Then, at the end of the fourth cycle, the total sum of the count values becomes 6, which is larger than the reference value 5, so that the rule is satisfied.

[0035]

As described above in detail, according to the present invention, it is possible to provide a position control device for a film coating device capable of optimally controlling the position of the gap between the web and the coater. In addition, when the X-ray film was applied by the above-mentioned application device according to the table of the rules in which such conditional expressions were actually set, the application of the X-ray film was uniform despite the vibration of the web on the complicated air roll. The proper gap was maintained without impairing the sex.

[Brief description of drawings]

FIG. 1 is a configuration block diagram showing an embodiment of the present invention.

FIG. 2 is a diagram showing an example of setting values of control rules.

FIG. 3 is a diagram showing an example of application of rules.

FIG. 4 is a conceptual diagram of a structure of a film coating device.

FIG. 5 is an enlarged cross-sectional view of a coating section.

[Explanation of symbols]

 3 Web 4 Coater 5 Air Roll 10 Gap Measuring Means 11 Control Unit 12 Control Value Table 13 Coater Drive Unit

Claims (3)

[Claims] 1. A position control device for a film coating device, which controls a position of a film coating coater arranged to face a gas-supported web so that the gap is within a certain range. Gap means for measuring the gap at a plurality of positions in the width direction is provided, and in response to the output of the gap measuring means, the coater position control is carried out in order from the one having a higher priority among a plurality of control rules provided in advance in the memory. A position control device for a film coating device, which is adapted to be used in. 2. The control value table in which the control rule is stored is such that the data of the gap obtained within a certain time is the number of conditional expressions out of the setting range or the condition for counting the number of gap measurement locations. The position control device for a film coating apparatus according to claim 1, wherein the formula is stored, and whether or not the control is performed is also determined based on the count value. 3. When performing film coating control using the coater, the control for avoiding a gap leading to coating failure is 1.
2. The film coating apparatus according to claim 1, wherein the control is performed corresponding to the data of the control cycle, and the control for keeping the vibration width of the gap within a safer and desirable range is performed while watching the data of one control cycle or more. Position controller.