JP4089057B2 - Film edge thickness measuring apparatus and film edge thickness measuring method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an apparatus and a method for measuring film edge thickness when manufacturing a film (including a sheet).
[0002]
[Prior art]
As a method for producing a resin film, for example, a method in which a thick unstretched film is formed using a T-shaped die by a melt extrusion method (extrusion method) and then subjected to longitudinal stretching / lateral stretching (biaxial stretching), etc. Such a film production method is usually carried out continuously from the extrusion of the molten raw resin to the winding of the product film after stretching.
[0003]
However, in the above film forming process, there is a case where the running film is torn, and when the torn occurs, the running of the film must be stopped and repaired, and thus the productivity is deteriorated. There is a problem.
[0004]
Such film breakage often occurs in the process of laterally stretching a thick film (the process of stretching in the width direction). This is due to the variation in thickness at the film edge, which causes stress in the thin part. It is considered that the rupture occurs and breaks starting from that portion.
[0005]
Therefore, for the purpose of preventing the tearing, a method has been proposed in which the thickness of the edge portion of the film before the transverse stretching process is adjusted so as to conform to the management reference value.
[0006]
Specifically, the edge portion is cut out as a sample from the film immediately before the transverse stretching step, and the thickness of the unstretched film is changed by adjusting the die slip of the T-shaped die, for example, based on the measurement result of the thickness. By this change, the film thickness immediately before the transverse stretching step is changed, and the thickness of the edge portion of the film immediately before the transverse stretching step is measured again and confirmed. Repeat until the edge thickness meets the control standard value (conventional method (1)). When the adjustment is completed, the process shifts to the start of actual production, and the thickness is not adjusted during the production.
[0007]
As described above, the conventional method (1) is an off-line type measuring method in which the film edge is sampled. Therefore, when the film is actually produced, that is, when the film is running and the film forming process is proceeding one after another. The film edge thickness cannot be adjusted, and the width of the die slip is determined in advance by measurement, adjustment, and confirmation as described above.
[0008]
However, in the actual production process, the film thickness constantly fluctuates over time, so if the film edge thickness is adjusted in advance as described above, the control standard value may be deviated, and the film is broken. There is a risk of causing.
[0009]
In addition, in the conventional method {circle around (1)}, it is necessary to discard all the extruded films until the adjustment of the edge thickness is completed, resulting in a production loss. Moreover, since it is the method of measuring one point at a time with a micrometer, it takes time. Further, when the measured value of the edge thickness is not easily within the allowable range of the management reference value, not only adjustment is required, but also the waste film is increased. In addition, the off-line type measuring method of the conventional example {circle around (1)} is dangerous because it is an operation of cutting a running film with scissors.
[0010]
Therefore, a method has been proposed in which β-rays or infrared rays are irradiated to a running film at the time of film formation, and the thickness is measured without contact with the film using this light beam (conventional method (2): online type). Measurement method).
[0011]
FIG. 8 is a diagram showing this on-line type measuring apparatus and film. The film 10 being formed is traveling in the direction of arrow C, and a non-contact type thickness measuring device 11 is provided on each of the left and right edge portions of the film 10. _R , 11 _L Is installed. The thickness measuring instrument 11 _R , 11 _L Is provided with a sensor 15 using β rays or infrared rays. The sensor 15 includes an irradiation unit (light projecting unit) 15a and a light receiving unit 15b.
[0012]
The thickness measurement method using this apparatus measures the attenuation when the irradiated β-rays or infrared rays pass through the film, and measures the film edge thickness based on the attenuation. Unlike ▼, the film does not need to be cut off and can be measured quickly. Therefore, it can be carried out during film formation, that is, as an on-line measurement method, and the loss of the film and the time required for measurement and adjustment can be reduced.
[0013]
[Problems to be solved by the invention]
However, since the conventional on-line type thickness measuring device is provided with measuring devices for the left and right edge portions, at least two measuring devices are required, and the cost is high because the sensor is expensive. There's a problem. In addition, when there is no installation place on one side (right side or left side in the film running direction) or when it cannot be installed on one side because it interferes with work, there is a problem that the online thickness measuring method cannot be introduced.
[0014]
On the other hand, the applicant of the above-mentioned conventional on-line type thickness measuring device that only measures the film thickness (conventional example (2)), inappropriate film thickness adjustment when the distance from the edge to the measuring point varies. Therefore, an on-line type film edge thickness measuring method capable of accurately measuring the thickness profile of the edge portion of the film has already been proposed (Japanese Patent Application No. 9-245772, hereinafter referred to as the invention of the prior application). Sometimes called).
[0015]
FIG. 7 is a view showing an example of the film edge thickness measuring apparatus and the film, and an infrared sensor (thickness measuring means) 25 for measuring the thickness. _R , 25 _L And an edge detection sensor (edge edge position detection means) 22 for detecting the edge edge position. _R , 22 _L Measuring instrument 21 equipped with _R , 21 _L Are installed at the left and right edge portions of the film 10 traveling in the direction of arrow C, respectively. The infrared sensor 25 _R , 25 _L And edge detection sensor 22 _R , 22 _L Is connected to a data processing computer 13, and the data processing computer 13 is further connected to a display device (CRT or the like) 14.
[0016]
Measuring instrument 21 _R , 21 _L Are traversed in the width direction of the film 10 in the vicinity of the edge (lateral movement: arrow D). _R , 22 _L And infrared sensor 25 _R , 25 _L Traverse to detect edge edge position and measure film thickness. Then, a thickness profile near the edge is obtained from the obtained data, and the thickness of the edge portion of the film is adjusted.
[0017]
Thus, in the above-mentioned prior invention, even when the film 10 meanders and the edge end position fluctuates greatly, the thickness profile based on the edge end can always be obtained with high accuracy.
[0018]
However, in the invention of the prior application, as described above, the number of sensors to be used is not considered, and the case where it cannot be installed on one side is not considered.Therefore, in the present invention, the number of sensors to be used is reduced. A film edge thickness measuring device and a film capable of reducing the cost, enabling an on-line type measuring device to be installed even when the measuring device cannot be installed on one side, and measuring the thickness profile of the edge portion of the film accurately and accurately An object is to provide an edge thickness measuring method.
[0019]
[Means for Solving the Problems]
The film edge thickness measuring device according to the present invention is a device for measuring the thickness of a film edge and / or the vicinity of the edge of the film before the transverse stretching process during the course of continuously manufacturing the film. Edge edge position detection that detects the position of the edge edge of the film by using a thickness measuring means for measuring the thickness using spot light narrowed down by an optical sensor and an optical sensor having a light projecting part and a light receiving part by a semiconductor laser Means are mounted on one measuring instrument, Further, the edge end position detecting means detects the edge end position when the amount of light received by the sensor decreases by a certain percentage with reference to the detected maximum light amount, The gist is that the measuring device is configured to be movable over the entire width in the width direction of the film, and is configured to measure the left end and the right end in the film running direction.
[0020]
The film edge thickness measuring method according to the present invention is a process of continuously manufacturing a film, Before the transverse stretching step In the method of measuring the thickness of the edge of the film and / or the edge, Using spot light that is squeezed through lens A thickness measuring sensor for measuring the thickness; Using an optical sensor with a light emitting part and a light receiving part by a semiconductor laser A measuring instrument equipped with an edge detection sensor for detecting the edge end position moves across the entire width direction of the film, The detection of the edge end position of the film is detected as the edge end position when the received light amount of the edge detection sensor is reduced by a certain percentage with reference to the detection maximum light amount of the edge detection sensor, Film travel direction left and right edges A thickness profile corresponding to the distance from each edge is obtained. This is the gist.
[0021]
In this way, since the left and right ends in the film running direction are respectively measured with one measuring instrument, the number of sensors used can be reduced, and thus the cost can be reduced. In addition, the measuring device can be installed even when the installation location of the measuring device cannot be secured on one side in the film running direction.
[0022]
Moreover, according to the measuring instrument, since the thickness of the edge of the film and / or the vicinity of the edge is measured while detecting the edge end position, the thickness profile from the edge end can be accurately obtained. The film edge thickness can be adjusted accurately.
[0023]
In the film edge thickness measuring apparatus according to the present invention, it is preferable that the measuring device has edge end position detecting means mounted on both sides of the thickness measuring means. In this apparatus, one edge end position detecting means detects the right edge end, and the other edge end position detecting means detects the left edge end.
[0024]
In the case of a measuring apparatus equipped with one thickness measuring means and one edge end position detecting means, the thickness measuring means is located on the film side (inside) and the edge end position detecting means is located outside on one edge. In the other edge, the edge edge position detecting means is located on the film side (inner side) and the thickness measuring means is located on the outer side, that is, the right and left edges are opposite, and the thickness profile is Computation processing when obtaining is complicated. However, in the case of the measuring apparatus in which the edge end position detecting means is mounted on both sides of the thickness measuring means as described above, the calculation process is simplified because the positional relationship is the same for the left and right edges.
[0025]
The measuring apparatus of the present invention may be one equipped with one thickness measuring means and one edge end position detecting means. In this case, since the number of edge end position detecting means is reduced to one, the cost can be further reduced.
[0026]
In the film edge thickness measuring method according to the present invention, at least before the start of film production, the measuring device first measures the thickness by reciprocating a plurality of times near one edge of the film, and this measured value is adjusted to the film thickness. The film edge thickness is adjusted by feeding back to the means, and then the measuring device measures the thickness by reciprocally scanning the vicinity of the other edge of the film a plurality of times, and this measured value is fed back to the film thickness adjusting means. It is preferable to adjust the edge thickness.
[0027]
In producing the film, preliminarily manufacture a small amount of film and adjust the film thickness (time before the start of film production), and then start full-scale film production. In the preliminary manufacturing stage, quick measurement is required from the viewpoint of reducing waste film.
[0028]
Therefore, as described above, first, the thickness of the one edge side is continuously measured repeatedly on one edge side (for example, the right side) of the film by reciprocally scanning the vicinity of the edge, thereby adjusting the edge thickness. . And when the one edge thickness falls within the management standard, the thickness of the other edge side is continuously measured repeatedly by reciprocating the vicinity of the edge a plurality of times on the other edge side (for example, the left side), Adjust the edge thickness. In this way, production starts when the left and right edge thicknesses fall within the management standard.
[0029]
Further, in the film edge thickness measuring method according to the present invention, the edge detection sensor is an optical sensor having a light projecting unit and a light receiving unit, and detects an edge end position based on data of the optical sensor. It is preferable to detect the edge end with reference to the maximum detection data level of the edge detection sensor.
[0030]
Since the maximum detection data level of the edge detection sensor is used as a reference in this way, if the maximum detection data level increases (the ambient atmosphere is clean, there is no turbulence, etc.), the data level recognized as an edge increases, and the maximum detection level If the data level is lowered (the ambient atmosphere is dirty, turbulent, etc.), the data level recognized as an edge is lowered. Therefore, even if the atmosphere of the surrounding environment changes, an actual edge portion can be recognized as an edge without being affected.
[0031]
BEST MODE FOR CARRYING OUT THE INVENTION
[Example 1]
FIG. 1 is a schematic perspective view showing a film edge thickness measuring apparatus and a film according to Embodiment 1 of the present invention.
[0032]
The film 10 being formed travels in the direction of arrow C, and one non-contact type measuring device 31 is disposed on the film 10. The measuring device 31 has one infrared sensor (thickness measuring means) 35 for measuring the thickness, left edge detection sensor (edge end position detecting means) 32 on both sides of the infrared sensor 35, and right edge detection. A sensor (edge end position detecting means) 33 is mounted. The measuring device 31 can be moved over almost the entire width in the film width direction (see arrow A shown in FIG. 1). By moving the measuring device 31 in this way, the infrared sensor 35 and the edge detection sensor. 32 and 33 come to be on the left and right edge portions of the film.
[0033]
The infrared sensor 35 and the edge detection sensors 32 and 33 are connected to a data processing computer (data analysis means) 13, and the data processing computer 13 is further connected to a display device (CRT or the like) 14.
[0034]
The infrared sensor 35 and the edge detection sensors 32 and 33 are respectively composed of light projecting portions 35a, 32a, and 33a and light receiving portions 35b, 32b, and 33b, and the light emitted from the light projecting portions 35a, 32a, and 33a is described above. The film thickness is measured and the edge end position is detected based on the attenuation due to the passage through the film 10 at this time, which is received by the light receiving portions 35b, 32b, 33b. The infrared sensor 35 uses spot light obtained by narrowing transmission infrared rays with a lens, and has high measurement resolution. The edge detection sensors 32 and 33 are made of semiconductor lasers capable of outputting data in analog form.
[0035]
<Measurement of film edge thickness during normal production: Measurement method (1)>
Next, a thickness measuring method using this film edge thickness measuring apparatus will be described.
[0036]
FIG. 2 is a diagram for explaining the measurement method of the present invention, and an arrow B ₁ ~ B ₇ Represents the position where the sensor of the measuring device 31 has passed over the film 10. Note that the measuring device 31 only moves in the width direction and not in the film traveling direction, but the film 10 travels in the direction of arrow C, so the trajectory passed by the sensor is zig-zag as shown in FIG. Become. Solid arrow B ₁ , B _Three , B _Five , B ₇ Represents a state in which the sensors 35, 32, and 33 are moving while being operated (measured), and an arrow B indicated by a two-dot chain line ₂ , B _Four , B ₆ Represents a state in which the sensors 35, 32, and 33 are moving without being activated.
[0037]
In the thickness measurement, the measuring device 31 is moved in the film width direction (the direction of arrow A shown in FIG. 1), and the film edge thickness is sequentially measured for the right edge portion and the left edge portion of the film 10.
[0038]
That is, the measuring device 31 always traverses in the width direction of the film 10, but when the sensor of the measuring device 31 is traversing on the right edge portion (arrow B). _Three ) Based on the edge edge position data detected by the right edge detection sensor 33, the thickness data from the infrared sensor 35 and the mechanical position data of the spot light of the infrared sensor 35 are made to correspond to each other, and the right side based on these data. Determine the film edge thickness profile.
[0039]
Next, when the sensor of the measuring instrument 31 is traversing the left edge portion (arrow B) _Five ) Based on the edge edge position data detected by the left edge detection sensor 32, the thickness data from the infrared sensor 35 and the mechanical position data of the spot light of the infrared sensor 35 are made to correspond to each other. Determine the film edge thickness profile.
[0040]
The traveling film 10 is meandering, and the edge end position fluctuates in the width direction. However, since the edge end position is always detected by the edge detection sensors 32 and 33, the thickness profile corresponding to the distance from the edge end. Is obtained.
[0041]
In this way, the left and right film edge thicknesses can be efficiently measured with one measuring device 31.
[0042]
The processing of the various data is performed by the data processing computer 13, but the film is accurately taken into consideration, such as the traveling speed of the film 10, the moving speed of the measuring instrument 31, the distance between the edge detection sensors 32, 33 and the infrared sensor 53, and the like. An edge thickness profile is obtained, and the obtained thickness profile data is sent to a display device and displayed in a graph.
[0043]
FIG. 3 is a diagram showing edge thickness analysis software provided in the data processing computer 13, where R is analysis software for the right edge, L is analysis software for the left edge, and the solid line of the graph indicates the measured value. The alternate long and short dash line indicates the allowable management width.
[0044]
The result of the thickness profile near the edge obtained as described above is sent to the display device 14 together with the management allowable width, and is displayed in a graph every moment. Then, the measured value is compared with the management allowable width, and the thickness of the unstretched film is adjusted by adjusting the die slip of the T-shaped die when forming the unstretched film, for example, so that the current film edge thickness is within the management allowable width. To adjust the thickness of the edge portion of the film before the transverse stretching step.
[0045]
By adjusting in this way, it is possible to reduce the number of times the film breaks due to defective edge thickness.
[0046]
Further, as described above, the measuring device 31 moves over the entire width of the film and detects the left and right edge end positions, so that the film width can also be measured, and therefore the fluctuation of the film width is monitored online. You can also.
[0047]
Such measurement of the film width is particularly effective for a product whose quality is greatly affected by only a few millimeter fluctuations in the film width. In addition, the fact that the film edge thickness and the film width can be measured simultaneously with one measuring device 31 can reduce the cost of the measuring equipment, and the measuring equipment can be installed in a small space.
[0048]
By automatically traversing the measuring device 31 in the width direction, the number of measurements per unit time can be increased, unlike the case of manually changing the measurement position in the width direction. Measurement time can be shortened. Therefore, the thickness adjustment time can be shortened, and the amount of film that cannot be produced can be reduced.
[0049]
<Measurement of film edge thickness before start of production: Measurement method (2)>
Next, a film edge thickness measuring method in a preliminary production stage in which only film thickness adjustment is performed before starting production of a film will be described.
[0050]
As described above, rapid measurement is desired in the preliminary manufacturing stage before starting full-scale film production. On the other hand, the measurement and adjustment of the film edge thickness is rarely performed once, and usually, the measurement and adjustment are repeated several times so that the thickness gradually falls within the management standard. However, when the left and right edge portions are measured alternately as shown in FIG. 2, the left and right edges are reciprocated many times, and in particular, from one edge (for example, the right edge) to the other edge. Since it takes time to move the measuring device 31 sensor to (for example, the left edge), quick measurement cannot be performed.
[0051]
Therefore, the following measurement method is recommended to quickly measure and adjust the thickness several times before the start of production.
[0052]
FIG. 4 is a diagram for explaining the measurement method before the start of production. ₁ ~ D ₁₇ Represents the position where the sensor of the measuring device 31 has passed over the film 10. As in the case of FIG. 2, the measuring device 31 does not move in the film traveling direction (only in the width direction), but since the film 10 is traveling in the direction of arrow C, the trajectory that the sensor has passed is It is zigzag as shown in FIG. Solid arrow D ₁ , D _Three , D _Five ... D ₁₇ Represents a state in which the sensors 35, 32, and 33 are moving while being operated (measured), and an arrow D indicated by a two-dot chain line ₂ , D _Four , D ₆ ... D ₁₆ Represents a state in which the sensors 35, 32, and 33 are moving without being activated.
[0053]
As shown in FIG. 4, first, the vicinity of the left edge is reciprocated several times (arrow D). ₁ ~ D _Five ) Repeat the thickness measurement and the thickness adjustment only for the left edge. When the left edge thickness falls within the management standard, the measuring instrument 31 is moved to adjust the right edge thickness (arrow D). ₆ ) By reciprocating the vicinity of the right edge a plurality of times (arrow D) ₇ ~ D ₁₃ ) Repeat the thickness measurement and the thickness adjustment only for the right edge so that the right edge thickness is within the management standard. Production is started when the thickness of the left and right film edges finally falls within the control standard in this way.
[0054]
Since only the vicinity of the edge on one side is reciprocated in this way, a plurality of measurements can be performed in a short time. That is, for example, the first measurement of the right edge shown in FIG. ₇ ) To the second measurement (arrow D) ₉ ) Time T ₀ Is the right edge measurement arrow B shown in FIG. _Three To right next edge measurement arrow B ₇ Time T ₁ It is much shorter than.
[0055]
During subsequent film production, as shown in measurement method (1) above, the measuring device 31 is moved over the entire width of the film so that the sensors are alternately placed on the left and right edges once (see the arrows in FIG. 4). D ₁₄ ~ D ₁₇ ... or arrow B in FIG. ₁ ~ B ₇ ...), the left and right edge thicknesses are measured alternately once. During film production, fluctuations in film thickness are gradual, so there is no need to perform multiple measurements in a short time as before the start of production. Whether or not can be sufficiently monitored.
[0056]
Switching between the zigzag movement on the left edge, the zigzag movement on the right edge, and the zigzag movement over the entire width of the film may be performed manually, but within the management criteria. You may make it switch automatically based on the information that it was settled.
[0057]
<Edge edge position detection means not affected by surrounding environment, etc .: Measurement method (3)>
Next, the edge end position detection means recommended in the present invention will be described.
[0058]
FIG. 5A is a diagram showing a state in which the measuring device 31 measures the left edge portion of the film 10, and FIG. 5B is an enlarged cross-sectional view of the left edge portion of the film 10, and FIG. (c) is a graph showing the amount of light reaching the light receiving part 32b (light reception amount) when using an edge end position detection means (edge detection sensor 32) capable of detecting the light reception amount as analog data. Examples of the edge detection sensor include a sensor using a semiconductor laser.
[0059]
The measuring device 31 moves in the film width direction (arrow A) and operates when the sensor comes on the edge portion, and detects the edge end position of the film and measures the film edge thickness.
[0060]
The edge end position is detected as the edge end position when the amount of light received by the edge detection sensor decreases by a certain percentage with reference to the maximum detected light amount (maximum detection data level) at that time. For example, assuming that the maximum detection data level value is M, the received light amount value is S, and the decrease rate is p%, the edge end position is detected when the received light amount value S reaches (p / 100) × M.
[0061]
If the edge detection sensor 32 is clean and the surrounding atmosphere is also clean, a certain percentage (p%) decrease with reference to the maximum detected light amount G as shown by the two-dot chain line in FIG. 5 (c). The detected light amount E is detected as an edge end. In an environment where the edge detection sensor 32 is dirty or the surrounding atmosphere is suspended, as shown in the graph shown by the solid line in FIG. Detection is made as an edge end by the received light amount F at the time of the decrease.
[0062]
Therefore, even if the maximum detected light amount is reduced due to dirt on the light receiving and projecting parts of the sensor, dirt on the surrounding atmosphere, etc., the detection level at the edge edge also decreases according to the detected maximum light amount. It is not detected as an end.
[0063]
FIG. 9 is a diagram for explaining a case where a sensor for detecting the presence / absence of a film is used as the edge end position detecting means based on whether or not a certain amount of received light is reached (reference method (1)). 9A is a view showing a state in which the measuring device 31 measures the left edge portion of the film 10, FIG. 9B is an enlarged sectional view of the left edge portion of the film 10, and FIG. c) is a graph showing the amount of light reaching the edge detection sensor light-receiving unit 32b (amount of received light) in a clean atmosphere environment, and (d) of FIG. 9 is a suspended atmosphere or the light-projecting unit 32a of the edge detection sensor. It is a graph of the amount of light (light reception amount) reaching the edge detection sensor light receiving part 32b when the light receiving part 32b is dirty.
[0064]
The edge edge position is detected as an edge edge when the amount of light received by the edge detection sensor decreases by a certain amount with respect to the maximum light amount G (E in the figure).
[0065]
When the measurement environment is clean and the photoelectric sensor is not soiled, it is detected as an edge edge at the actual edge edge position of the film 10 as shown in FIG.
[0066]
However, for example, if the light projecting part 32a or the light receiving part 32b of the edge detection sensor is dirty, the amount of received light is reduced as shown in FIG. 9 (d). That is, the edge end position is erroneously detected.
[0067]
In this way, the edge detection sensor malfunctions due to whether the edge detection sensor is clean or dirty, the measurement environment is clean or suspended, or the film material or thickness differs, and the sensor has been used for many years. In some cases, output fluctuations may occur and malfunction may occur, so that an edge detection sensor that determines whether or not a certain amount of light is received as described above may not provide an accurate film edge thickness profile. However, in the measurement method {circle around (3)}, when the received light amount is reduced by a certain percentage from the detected maximum data, the edge end position is detected based on the detected maximum data level of the edge detecting sensor. It is possible to correctly detect the actual edge position without being affected by.
[0068]
[Example 2]
FIG. 6 is a configuration diagram when an edge thickness automatic control system is added to the film edge thickness measuring apparatus of the first embodiment, and an automatic thickness adjusting apparatus (for adjusting the thickness of the film 10 on the upstream side of the traveling film 10). Film thickness adjusting means) 16 is provided. In FIG. 6, the same components as those in FIG.
[0069]
Also in the second embodiment, the left and right film edge thicknesses are efficiently measured by one measuring device 31 as in the first embodiment. Then, the data processing computer 13 obtains the deviation between the measured value and the management reference value, and feeds back the deviation to the automatic thickness adjusting device 16 to adjust the thickness of the film 10 so that the deviation is reduced.
[0070]
In this way, the management of the edge thickness is automatically performed, and as a result, the number of breaks of the film due to the defective edge thickness is reduced. Furthermore, since the thickness is automatically adjusted, no manpower is required.
[0071]
As described above, the film edge thickness measuring apparatus and the measuring method according to the present invention have been specifically described with reference to the drawings showing the embodiments, but the present invention is not limited to the above examples, The present invention can be implemented with appropriate modifications within a range that can be adapted to the gist of the present invention, and all of them are included in the technical scope of the present invention.
[0072]
For example, the thickness measuring means and the edge end position detecting means are not limited to the infrared sensor and the semiconductor laser type edge detecting sensor, and may be other sensors.
[0073]
In the first and second embodiments, the measuring device 31 including two edge detection sensors is used. However, the measuring device 31 may include only one edge detection sensor. The positions of the left and right edges will be detected.
[0074]
【The invention's effect】
As described above, in the present invention, since the film edge thickness can be measured with one measuring instrument, the equipment cost can be reduced by reducing the number of sensors used, and when there is no measuring instrument installation place on one side of the film. In addition, the thickness profile of the edge portion of the film can be measured accurately and accurately online, and the production loss can be reduced.
[Brief description of the drawings]
FIG. 1 is a schematic perspective view showing a film edge thickness measuring apparatus and a film according to Embodiment 1 of the present invention.
FIG. 2 is a diagram for explaining an example of a film edge thickness measuring method according to the present invention during normal production.
FIG. 3 is a diagram showing edge thickness analysis software provided in a data processing computer.
FIG. 4 is a view for explaining an example of a film edge thickness measuring method according to the present invention before the start of production.
FIG. 5 is a diagram for explaining an example of an edge end position detecting means in the film edge thickness measuring method of the present invention.
FIG. 6 is a schematic perspective view showing a film edge thickness measuring apparatus and a film according to Embodiment 2 of the present invention.
FIG. 7 is a diagram illustrating an example of a film edge thickness measuring apparatus and a film according to the invention of the prior application.
FIG. 8 is a diagram showing a conventional online measuring device and film.
FIG. 9 is a diagram for explaining a case where a sensor for detecting the presence / absence of a film depending on whether or not a certain amount of received light is reached is used as edge edge position detection means.
[Explanation of symbols]
10 films
13 Data processing computer
14 Display device
16 Automatic thickness adjuster
31 Measuring instrument
32 Edge detection sensor for left side
32a, 33a, 35a Emitting unit
32b, 33b, 35b
33 Right edge detection sensor
35 Infrared sensor

Claims (6)

In the process of continuously manufacturing the film, in the apparatus for measuring the thickness of the edge of the film and / or the vicinity of the edge before the transverse stretching step during running,
The position of the edge of the film is detected using a thickness measuring means that measures the thickness using spot light obtained by narrowing a transmission infrared ray with a lens, and an optical sensor having a light projecting portion and a light receiving portion using a semiconductor laser. The edge edge position detecting means to be mounted on one measuring device,
The edge end position detection means detects the edge end position when the amount of light received by the sensor decreases by a certain percentage with reference to the detected maximum light amount,
The film edge thickness measuring apparatus, wherein the measuring device is configured to be movable over the entire width in the width direction of the film, and is configured to measure the left end and the right end in the film running direction.   2. The film edge thickness measuring apparatus according to claim 1, wherein the measuring device has the edge end position detecting means mounted on both sides of the thickness measuring means.   The film edge thickness measuring device according to claim 1 or 2, wherein an automatic thickness adjusting device for adjusting the thickness of the film is provided on the upstream side of the measuring device. In the process of continuously manufacturing the film, in the method of measuring the thickness of the edge of the film and / or the vicinity of the edge before the transverse stretching step during running,
An edge detection sensor that detects the edge end position using a thickness measurement sensor that measures the thickness using spot light obtained by narrowing a transmission infrared ray with a lens, and an optical sensor that includes a light projecting unit and a light receiving unit using a semiconductor laser. And a measuring instrument equipped with a moving across the entire width direction of the film,
The detection of the edge edge position of the film is detected as the edge edge position when the amount of light received by the edge detection sensor is reduced by a certain percentage with reference to the maximum light intensity detected by the edge detection sensor, And a method for measuring a film edge thickness, characterized in that a thickness profile corresponding to the distance from the edge edge of each right edge is obtained. It is a thickness adjustment method by the film edge thickness measurement method according to claim 4,
At least before the start of film production, the measuring instrument first measures the thickness by reciprocally scanning the vicinity of one edge of the film multiple times, and feeds back the measured value to the film thickness adjusting means to adjust the film edge thickness. Then, the measuring device measures the thickness by reciprocally scanning the vicinity of the other edge of the film a plurality of times, and feeds back the measured value to the film thickness adjusting means to adjust the film edge thickness. .   The result of the thickness profile near the edge obtained by the film edge thickness measurement method according to claim 4 is compared with the management allowable width, and an unstretched film is formed so that the current film edge thickness is within the management allowable width. An adjustment method comprising adjusting a film edge thickness by adjusting a die slip of a T-shaped die and changing a thickness of an unstretched film.

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