JPH03286829A - Film thickness-regulating method and its device - Google Patents

Abstract

PURPOSE:To heighten the regulation precision of film-thickness by a method in which the correcting displacement-amount of each lip piece corresponding to film thickness-correcting amount is computed by accumulating the deviations between the mean value of whole width and the mean value of partial width, and the position of each lip piece is controlled, based on said correcting displacement amount, and then this process is repeated. CONSTITUTION:A film thickness-measurer 6 is caused to scan the film in the width direction of a film. While mean value of the whole width which is the mean value of the value from the film thickness value measured in each one scanning by the measurer 6, is computed, the mean value of partial width which is the mean value of the film thickness-value in every partial width corresponding to each lip piece 1b1, is computed. The deviation between the mean value of whole width and the mean value of partial width is calculated, and the correcting amount of film thickness is computed by accumulating the deviation at each partial width in every scanning by the film thickness-measurer 6. The correcting displacement amount of each lip piece 1b1 corresponding to said film thickness-correcting amount is computed, and the position of each lip piece 1b1 is controlled, based on said correcting displacement-amount.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is applicable to a film processing machine that uses an extrusion die equipped with a movable lip mechanism to form a resin film so that the film thickness is uniform. The present invention relates to a method and device for adjusting film thickness.

[Prior Art] Conventionally, as a film thickness adjusting device used in this type of film processing machine, the amount of change in the gear/lub spacing of an extrusion die and the amount of change in film thickness of the film are in a predetermined correspondence relationship. Methods for controlling gap spacing are known.

[Problems to be Solved by the Invention] However, in the film thickness adjusting device used in conventional film processing machines, the correspondence between the amount of change in the gap interval of the extrusion die and the amount of change in the film thickness depends on the temperature of the resin, etc. Therefore, there is a problem that the control accuracy of the film thickness is not good.

An object of the present invention is to improve the control accuracy of the film thickness even if the correspondence between the amount of change in the gap interval of the extrusion die and the amount of change in the film thickness changes due to the influence of resin temperature, etc. The object of the present invention is to provide a method and device for adjusting film thickness.

[Means for Solving the Problem] According to the present invention, an extrusion die equipped with a movable lip mechanism that can change the gap interval by individually displacing a plurality of lip pieces arranged in parallel is used. In a film thickness adjustment method for adjusting the film thickness of a film in a film processing machine that molds a resin film so that it has a film thickness similar to that of a resin film.

A film thickness meter is scanned in the width direction of the film, and a total width average value is calculated from the film thickness values measured each time the film thickness meter is scanned, and a total width average value corresponding to each lip piece is calculated. The partial width average value, which is the average value of the film thickness values for each partial width, is calculated, and the deviation between the full width average value and the partial width average value is calculated, and 1. Calculate the film thickness correction amount by accumulating the deviation for each partial width for each scan of the meter,
Further, a film thickness adjustment method is obtained which is characterized in that the correction displacement amount of each lip piece corresponding to these film thickness correction amounts is calculated and the position of each lip piece is controlled based on these correction displacement amounts. It will be done.

Further, according to the present invention, the thickness of the resin film is adjusted using an extrusion die equipped with a movable lip mechanism that can change the gap distance by individually displacing a plurality of lip pieces arranged in parallel. A film thickness adjustment device that adjusts the film thickness of a film in a film processing machine that forms the film uniformly includes a film thickness meter that scans in the width direction of the film to measure the film thickness; Full-width average value calculating means for calculating a full-width average value that is an average value of the film thickness values measured for each scan.

Partial width average value calculating means for calculating a partial width average value, which is an average value of film thickness values for each partial width corresponding to each lip piece, from the film thickness value measured for each scan of the film thickness meter; , a deviation calculation means for calculating the (ki difference) between the full width average value and the partial width average value, and a film thickness correction amount is calculated by accumulating the deviation for each partial width for each scan of the film thickness meter. a film thickness correction amount calculation means for calculating a correction displacement amount of each lip piece corresponding to the film thickness correction amount, a lip piece correction displacement amount calculation means for calculating a correction displacement amount of each lip piece corresponding to the film thickness correction amount, and controlling the position of each lip piece based on the correction displacement amount. There is obtained a film thickness adjusting device characterized in that it is equipped with a lip position control means.

[Function] The present invention calculates the total width average value, which is the average value, and the film thickness for each partial width corresponding to each lip, from the film thickness values measured once per scan in the width direction of the film thickness meter. The partial width average value, which is the average value of the thickness values, is calculated, and the deviation between the full width average value and the partial width average value is calculated.

A film thickness correction amount is calculated by accumulating the deviations for each partial width for each scan of the film thickness meter, and a correction displacement amount of each lip piece corresponding to these film thickness correction amounts is calculated. By repeatedly controlling the position of each lip piece based on these corrected displacement amounts, the deviation between the full width average value and the partial width average value can be brought close to 0.

[Example] Next, one embodiment of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a schematic diagram showing an outline of an embodiment of the present invention.

In FIG. 1, reference numeral 1 indicates an extrusion die. A resin film 2 is extruded from this extrusion die 1. This film 2 is cooled and solidified by a cooling roller 3, and guided by a guide roller 4.5 to a winding device! (not shown).

A film thickness gauge 6 is placed on the film 2. As shown in FIG. 2, this film thickness meter 6 is scanned back and forth in a direction perpendicular to the longitudinal direction of the film 2 (ie, the running direction a) by a scanning device 7.

The film thickness signal from the film thickness gauge 6 and the scanning position signal from the scanning device 7 indicating the position of the film thickness gauge 6.

At the same time, it is applied to the storage section 9 of the microcomputer 8. Based on the information in the storage section 9 of the microcomputer 8, the calculation section 10 calculates the corrected displacement amount of each lip piece 1bl of the extrusion die 1, and provides this corrected displacement amount to the gap interval control device 11. This gap interval control device controls the position of each clip piece 1bl of the extrusion die 1.

FIG. 3 shows one embodiment of the extrusion die 1, which will be described below.

The extrusion die 1 has a gap G for extruding the resin.
It has lips la and lb forming a. The distance between the gaps G is g. One lip 1a is formed so that it cannot be displaced. The other lip 1b consists of a plurality of lip pieces 1b1 arranged in parallel in the longitudinal direction of the gap G. These lip pieces 1bl have a thin elastic part 1b2 at the base and a flexible piece 1b3 at the projecting part. These flexible pieces 1b3.

It is formed at a predetermined distance from the die body.

A plurality of bellows 1c are arranged between these flexible pieces 1b3 and the die body.

By changing the pressure of the compressed gas supplied to the Heroes IC,
The pressing force against the flexible piece 1b3 is reduced.

The elastic portion 1b2 of the knob piece 1bl is deformed to form the lip L1.
1b The position of 1 changes. Since the compressed gas pressure supplied to multiple bellows ICs can be changed individually,
The position of each lip piece 1bl can be changed independently of the others. When the position of each lip piece 1b1 changes, the gap distance g between it and the opposing lip 1a changes. The compressed gas pressure supplied to the bellows 1c is:
It is controlled by a gap interval control device 11.

Note that the movable lip mechanism for displacing the lip piece 1b1 is not limited to the embodiment shown in FIG.

Next, the arithmetic unit 1 of the microcomputer 8 described in ili′i3
The calculation at 0 will be explained in detail based on FIG.

FIG. 4 schematically shows calculations in the calculation section 10 of the microcomputer 8.

Film thickness f = No. d from the film thickness meter 6 and scanning device 7
The scanning position signal X from 1 is applied to the memory 12 and stored sequentially. At the end of one scan, the memory 12
The film thickness signal d is transferred to the memory 13, or at the time of this transfer, the film thickness signal d is averaged for each partial width corresponding to each lip piece 1b1, and the average value d of these partial widths is calculated.
, ~dゎ are stored in the memory 13.

The partial width average values d1 to d stored in the memory 13 are provided to a full width average value calculating section 14 and n adders 15. The above-mentioned all-axis average value calculation a'J 14 is a partial average value d
, ~d, the calculation of (d l +d2+·-d,)/n is performed to obtain the full width average value da+ean, which is supplied to n adders 15. These adders 15 calculate the full width average value d
Partial width average value d, ~d for mean. deviation Δdl
ll-+l to ΔdRtto++ are calculated and given to the memo 16.

The deviation Δd zk+++~Δ stored in this memory 16
d nLk. 1. is the n memory 17 (deviation Δd 11k in the previous scan of the film thickness gauge 6 stored)
)~Δd,. are added by an adder 18 and these added values are provided to the memory 17.

The added value stored in the memory 17 is multiplied by the adjustment gain K in the multiplier 19 to obtain the film thickness correction amount Δ.
Find d3.1~Δd mrml.

The second film thickness correction amounts Δd+taj to Δdnta are multiplied by a gain 1/C in a multiplier 20 to obtain correction amounts Δg1 to Δg7 for the gap distance g corresponding to each lip piece 1bl.

Here, C-6676g is a coefficient indicating the relationship between the gap interval change amount Δg and the film thickness change amount Δd.

The correction amounts Δg1 to Δg7 for the gap distance g are provided to the lip piece correction displacement amount calculating section 21. This lip piece correction displacement amount calculation unit 21 calculates the correction amount Δg1 to Δg of the gap interval g.
7, the corrected displacement amounts ΔS1 to ΔS1 of each lip piece 1b1 corresponding to these are calculated and provided to the gap interval control device 11.

This gap interval control device 11 has a correction displacement amount ΔS1~
The position of each lip piece 1bl is controlled based on ΔS.

If the operations of the arithmetic unit 10 of the microcomputer 8 and the gap interval control device 11 described above are repeated for each scan of the film thickness gauge 6, the deviation of the partial width average value d, ~d, with respect to the total width average value d of the film 2 5can is obtained. For example, Δd1 to Δd7 approach 0, as shown by curve A in diagram M5.

[Effects of the Invention] According to the present invention, even if the correspondence between the amount of change in the gap interval of the extrusion die and the amount of change in the film thickness changes due to the influence of resin temperature, etc., the control accuracy of the film thickness can be maintained. can be improved.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram showing an outline of an embodiment of the present invention. 2 is a diagram showing the relationship between the film thickness gauge and the film in the embodiment shown in FIG. 1, FIG. 3 is a partially cutaway perspective view showing the extrusion die in the embodiment shown in FIG. 1, and FIG. A schematic diagram schematically showing the calculation unit of the microcomputer in the embodiment shown in the figure, and FIG. It is a figure which shows the relationship with the deviation of 1... Extrusion die, la, lb... lip, 1b1
... Lip piece 2g... Gap interval, 6... Film thickness gauge, 8... Microcomputer, 10... Arithmetic unit, 11... Gap interval control device. 11r! j! J Figure 2

Claims (2)

[Claims] (1) Using an extrusion die equipped with a movable lip mechanism that can change the gap distance by individually displacing multiple lip pieces arranged in parallel, the resin film can be made to have a uniform thickness. In a film thickness adjustment method for adjusting the film thickness of a film in a film processing machine that forms the film, a film thickness meter is scanned in the width direction of the film, and the film thickness measured every time the film thickness meter is scanned. From these values, calculate the total width average value, which is the average value of these values, and calculate the partial width average value, which is the average value of the film thickness values for each partial width corresponding to each lip piece, and calculate the total width average value and the partial width average value. A film thickness correction amount is calculated by calculating the deviation from the film thickness correction value and accumulating the deviation for each partial width for each scan of the film thickness meter, and each lip corresponding to these film thickness correction amounts is calculated. A method for adjusting film thickness, comprising calculating corrected displacement amounts of the pieces and controlling the position of each lip piece based on these corrected displacement amounts. (2) Using an extrusion die equipped with a movable lip mechanism that can change the gap distance by individually displacing multiple lip pieces arranged in parallel, the resin film can be made to have a uniform thickness. A film thickness adjustment device for adjusting the film thickness of a film in a film processing machine that forms the film includes a film thickness meter that scans in the width direction of the film to measure the film thickness, and a single scan of the film thickness meter. a full-width average value calculation means for calculating a full-width average value, which is an average value, from the film thickness values measured for each lip piece; a partial width average value calculating means for calculating a partial width average value which is an average value of film thickness values for each corresponding partial width; a deviation calculating means for calculating a deviation between the full width average value and the partial width average value; a film thickness correction amount calculating means for calculating a film thickness correction amount by accumulating the deviation for each partial width for each scan of the film thickness meter; and a correction displacement amount of each lip piece corresponding to the film thickness correction amount. What is claimed is: 1. A film thickness adjusting device comprising: lip piece correction displacement calculation means for calculating the correction displacement amount; and lip position control means for controlling the position of each lip piece based on the correction displacement amount.