JP2001165649A - Measuring method and device for thickness profile - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method and device for precisely measuring the thickness profile of the whole width of a web in no contact as much as possible. SOLUTION: This measuring method for thickness profile comprises the process of detecting the lateral non-contact thickness profile signal of the web under traveling; the process of detecting the contact thickness profile signal; the process of calculating the thickness profile from the resulting non-contact thickness profile signal and contact thickness profile signal; and the process of switching the contact measuring mode and the non-contact measuring mode.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a measuring method and apparatus for measuring a thickness profile of a running web in the width direction. More specifically, the present invention relates to a thickness profile measuring method and apparatus capable of measuring a thickness profile of the entire width of a web with high accuracy and as little contact as possible.

[0002]

2. Description of the Related Art As shown in FIG. 5, a contact-type thickness profile measuring device includes a contact thickness measuring head 51 installed on an upper portion of a beam of a scan frame 13 and a contact thickness measuring device installed opposite to a lower portion of a beam. This is a device for measuring the thickness of the web 1 in the width direction by the measurement lower head 52. For example, Japanese Utility Model 2-1289
As disclosed in US Pat. No. 10, there is known an apparatus for measuring a web 1 by sandwiching a web 1 between a contact thickness upper head 51 and a contact thickness lower head 52 each composed of a target and a contact type sensor.

As shown in FIG. 6, a non-contact thickness profile measuring apparatus includes a non-contact thickness measuring head 61 installed above a beam of a scan frame 13 and a measuring guide roll 62 for tensioning the web. 1 is a device for measuring the thickness in the width direction. A laser displacement meter is installed inside the non-contact thickness measuring head 61. Further, as disclosed in Japanese Utility Model Laid-Open Publication No. 59-32907, an apparatus for measuring both sides of the web 1 with a laser displacement meter without using the measurement guide roll 62 is also known.

[0004] Conventional thickness profile measurement devices have measurement problems.

[0005] The contact-type thickness profile measuring device measures in contact with the web, so that when the contact thickness measuring head enters the web, the measuring portion is opened, so that the measurement cannot be performed. However, there is a problem that contact marks remain.

For example, the thickness of the paper is 53.9 ± 4.9 k
JIS standard for measurement under a constant pressure of Pa (P8118
-1994). However, since the non-contact thickness profile measuring device cannot press the web at the specified pressure,
The measured value cannot be treated as an absolute value, and it is necessary to correct the measured value using a calibration curve.

[0007] Conventionally, a web such as paper is processed into a thickness by a calender and finally wound up into a cylindrical shape. At this time, the thickness after processing is measured using a thickness profile measuring device to control product quality and winding quality. If the part is thick, the winding will be distorted and blistering will occur, deteriorating the winding quality. Particularly when the ears are thick, quality problems such as cracks in the ears may occur. Therefore, it is desired to accurately measure and manage the thickness profile of the entire width of the web without contact.

[0008]

SUMMARY OF THE INVENTION An object of the present invention is to provide a method and an apparatus for measuring the thickness profile of the entire width of a web with high accuracy and as little contact as possible.

[0009]

The present inventors have made intensive studies in view of the above and, as a result, have invented a method and an apparatus for measuring a thickness profile according to the present invention. That is, the method for measuring the thickness profile of the present invention includes a step of detecting a non-contact thickness profile signal in the width direction of the running web, a step of detecting the contact thickness profile signal, and a step of detecting the obtained non-contact thickness. A step of calculating a thickness profile from the thickness profile signal and the contact thickness profile signal; and a step of switching between a contact measurement mode and a non-contact measurement mode.

In the method for measuring a thickness profile according to the present invention, a step of detecting a non-contact thickness profile signal;
In the case of the contact measurement mode in which the step of detecting the contact thickness profile signal is always performed simultaneously, the step of calculating the thickness profile includes the following steps 1) to 5). 1) a step of obtaining a difference profile signal from a non-contact thickness profile signal and a contact thickness profile signal of the same section of the web 2) a step of obtaining an average correction amount from the difference profile signal 3) a non-contact in an unmeasured portion of the contact thickness profile Step of correcting the thickness profile signal by the average correction amount obtained in step 2) 4) Combining the corrected non-contact thickness profile signal and the contact thickness profile signal of the corrected unmeasured portion obtained in step 3) 5) a step of repeating steps 1) to 4)

In the method of measuring a thickness profile according to the present invention, a step of detecting a non-contact thickness profile signal is always performed, and a step of detecting a contact thickness profile signal is performed only once. In the case of (1), the step of calculating the thickness profile includes the following 1) to
It is characterized by comprising the step of 5). 1) a step of obtaining a difference profile signal from the non-contact thickness profile signal and the contact thickness profile signal of the same section of the web 2) a step of obtaining an average correction amount from the difference profile signal 3) the non-contact thickness profile signal of 2) A step of creating a thickness profile signal by correcting with the average correction amount obtained in the step 4) a step of performing steps 1) to 2) at the first measurement at the time of changing the grade 5) a step of constantly performing the step of 3)

The thickness profile measuring apparatus of the present invention comprises:
Non-contact thickness profile signal detection means in the width direction of the running web, contact thickness profile signal detection means, and means for calculating a thickness profile from the obtained non-contact thickness profile signal and contact thickness profile signal And means for switching between the contact measurement mode and the non-contact measurement mode.

Further, in the thickness profile measuring apparatus according to the present invention, the non-contact thickness profile signal detecting means includes means for blowing air to hold down the paper and means for measuring the thickness in a non-contact manner by a laser displacement meter. Wherein the contact thickness profile signal detecting means comprises means for measuring the thickness by contact with an eddy current type displacement meter or a differential transformer type displacement meter.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A method and an apparatus for measuring a thickness profile according to the present invention will be described in detail with reference to the drawings.

An apparatus for measuring a thickness profile according to the present invention is configured as shown in FIG. FIG. 1 is a schematic diagram in which the thickness profile measuring device of the present invention is applied to web measurement. In FIG. 1, 1 is a web, 2 is a contact thickness profile signal detecting means and a non-contact thickness profile signal detecting means, 3 is a thickness profile calculating means, 14 is a contact thickness profile signal, and 15 is a non-contact thickness profile A signal, 16 is a thickness profile signal, and 17 is a thickness profile display device.

The contact thickness profile signal detecting means and the non-contact thickness profile signal detecting means 2 comprise an upper head 11 for measuring thickness, a lower head 12 for measuring thickness, and a scan frame 13.

The contact thickness profile signal 14 and the non-contact thickness profile signal 15 in the width direction of the web 1 are provided so as to be opposed to the thickness measuring head 11 installed on the upper part of the beam of the scan frame 13 and the lower part of the beam. The thickness is measured with the lower head 12.

FIG. 2 is a configuration diagram of a thickness measuring head of the thickness profile measuring apparatus of the present invention. In FIG. 2, 1 is a web, 11 is an upper head for thickness measurement, and 12 is a lower head for thickness measurement. The head 11 for thickness measurement comprises a contact type displacement meter 21, a web holding air nozzle 23, and a non-contact displacement meter 22. The thickness measurement lower head 12 is
The web measuring table 24 is configured. Air nozzle 23 for web holding, contact displacement meter 21, non-contact displacement meter 22
Are arranged in the same direction as the traveling direction of the web 1. The distance between the thickness measurement upper head 11 and the thickness measurement lower head 12 is fixed so as to be always constant.

As the contact type displacement meter 21, an eddy current type displacement meter or a differential transformer type displacement meter is used. In the case of the eddy current type displacement meter, the detecting portion comes into contact with the web, and a specified load is simultaneously applied. By measuring the distance between the detection unit and the web measuring table 24, the thickness of the web 1 can be measured. Stainless steel, aluminum, copper, iron, and the like can be used as the material of the web measuring table 24, but stainless steel is preferable in terms of abrasion resistance and corrosion resistance.

The differential transformer type displacement meter also has a structure in which the detecting portion comes into contact with the web and simultaneously applies a specified load. By measuring the distance between the detection unit and the web measuring table 24, the thickness of the web 1 can be measured.

As the non-contact displacement gauge 22, a laser displacement gauge is used. Although the laser displacement meter measures the distance to the web 1, the thickness of the web 1 can be measured by calculating the difference between the known distance between the laser displacement meter and the web measuring table 24. . Although the phenomenon of flapping or warpage of the edge often occurs on the web 1,
By supplying a constant and low-pressure air to the web holding air nozzle 23, flapping and warpage of the edge are suppressed, and stable measurement is possible.

FIG. 3 shows a principle diagram of the measuring operation of the thickness profile measuring apparatus of the present invention. In FIG. 3, reference numeral 1 denotes a web, 31 denotes a measurement track of a contact displacement meter, 32 denotes a non-measurement range of the contact displacement meter, and 33 denotes a simultaneous measurement range.

When the full width of the web 1 is measured, the non-measurement range 32 of the contact type displacement meter 21 occurs because the contact type displacement meter 21 opens the detecting portion when entering the web 1. On the other hand, the non-contact displacement meter 22 can measure the entire width of the web 1. Therefore, the range where the contact type displacement meter 21 and the non-contact type displacement meter 22 can measure simultaneously is the illustrated simultaneous measurement range 33.

When the contact measurement mode is selected, the step of detecting the contact thickness profile signal and the step of detecting the non-contact thickness profile signal are always performed simultaneously. When the measurement is completed by traversing the web 1 once, the calculation processing of the thickness profile of the following steps 1 to 4 is performed every time.

In step 1, each signal of the simultaneous measurement range 33 is extracted from the contact thickness profile signal 14 and the non-contact thickness profile signal 15, and a process of calculating a difference profile signal of the same measurement portion is performed.

In step 2, a process of averaging the difference profile signals and calculating an average correction amount is performed.

In step 3, a thickness profile signal of the non-contact displacement meter non-measurement range 32 is extracted from the non-contact thickness profile signal 15 and a process of correcting the thickness profile signal with an average correction amount is performed.

In step 4, a process of calculating the thickness profile signal 16 by combining the corrected non-contact thickness profile signal of the contact type displacement meter unmeasured range 32 processed in step 3 and the contact thickness profile signal 14 is performed. .

When the non-contact measurement mode is selected, the step of detecting the non-contact thickness profile signal is always performed, and the step of detecting the contact thickness profile signal is performed only once. At the start of measurement, at the time of completing the measurement once across web 1 at the time of grade change, the following step 1
Is calculated only once.

In step 1, each signal of the simultaneous measurement range 33 is extracted from the contact thickness profile signal 14 and the non-contact thickness profile signal 15, and a process of calculating a difference profile signal of the same measurement portion is performed.

In step 2, a process of averaging the difference profile signal and calculating an average correction amount is performed.

In step 3, the non-contact thickness profile signal 15 is corrected by the average correction amount, and the process of calculating the thickness profile signal 16 is performed.

After the above processing is completed, when the measurement is completed by traversing the web 1 once, the following calculation of the thickness profile in step 4 is performed every time.

In step 4, a process of correcting the non-contact thickness profile signal 15 with the average correction amount and calculating the thickness profile signal 16 is performed.

[0035]

Embodiments of the present invention will be described below with reference to the drawings.

Example 1 A thickness profile measuring apparatus shown in FIGS. 1 and 2 was manufactured. The contact type displacement meter 21 is an eddy current type displacement meter (manufactured by Keyence Corporation: EX-505, EX-016), and the non-contact type displacement meter 22 is a laser type displacement meter (manufactured by Keyence Corporation: LC-2).
400, LC-2440), and the web holding air nozzle 23 is a filled conical nozzle (manufactured by Ikeuchi Co., Ltd .: 1 / 4MJ14).
0S303W), the web measuring table 24 is made of stainless steel (SU
S304) The computer (PC / AT compatible) was used as the thickness profile calculation means 3 and the thickness profile display device 17. The scan frame 13, the upper head 11 for thickness measurement and the lower head 12 for thickness measurement were self-made.

Although not shown, the web holding air nozzle 23 shown in FIG. 2 is supplied with air having a reduced pressure of 50 to 100 kPa using a pressure reducing valve. The contact thickness profile signal 14 and the non-contact thickness profile signal 15 were taken into a computer using an A / D converter.

The contact type displacement meter 21 was adjusted to zero by bringing the detection section into contact with the web measuring table 24. The non-contact displacement meter 22 measured the distance from the web measuring table 24 and stored it in the computer.

Using the thus constructed apparatus, high quality paper was measured in the contact measurement mode.

Example 2 The same apparatus as in Example 1 was used, and high quality paper was measured in the non-contact measurement mode.

FIG. 4 shows one example of the thickness profile obtained in Example 1 and Example 2. In FIG.
41 is a contact thickness profile, 42 is a non-contact thickness profile, 43 is a thickness profile in the contact measurement mode, 4
4 is a thickness profile in the non-contact measurement mode.

Thickness profile 43 in contact measurement mode
In the figure, the unmeasured range on the left side of the contact thickness profile 41 is measured, so that the entire width of the web can be measured. The thickness profile 44 in the non-contact measurement mode can also measure the full width of the web.

In the non-contact measurement mode, contact measurement is performed only once at the start of measurement and when the grade is changed, and the average correction amount is calculated. Therefore, the average correction amount is not updated until the next grade change. On the other hand, in the contact measurement mode, the average correction amount is constantly updated by performing constant contact measurement.

When the contact measurement mode and the non-contact measurement mode are compared, the contact measurement mode is superior to the non-contact measurement mode in the measurement followability and the measurement accuracy with respect to the thickness fluctuation at the same grade measurement.

On the other hand, the non-contact measurement mode is suitable for the measurement of a web where contact measurement is not preferable, and the average correction amount is updated each time the grade is changed. The measurement accuracy is higher than the device.

Therefore, the thickness profile measuring apparatus of the present invention can select and measure the contact measurement mode and the non-contact measurement mode as appropriate according to the conditions such as the material or use of the web and the required measurement accuracy. is there.

Although the present invention has been described based on the embodiments, the present invention is not limited to the embodiments and can be variously modified.

[0048]

As described above, according to the present invention, the thickness profile of the entire width of the web can be measured with high accuracy and as little contact as possible.

[Brief description of the drawings]

FIG. 1 is a schematic diagram in which a thickness profile measuring apparatus according to the present invention is applied to web measurement.

FIG. 2 is a configuration diagram of a thickness measuring head of the thickness profile measuring device of the present invention.

FIG. 3 is a diagram illustrating a principle of a measuring operation of the thickness profile measuring apparatus according to the present invention.

FIG. 4 is an example of a thickness profile measured by the thickness profile measuring apparatus of the present invention.

FIG. 5 is a schematic diagram of a conventional contact-type thickness profile measuring device.

FIG. 6 is a schematic diagram of a conventional non-contact type thickness profile measuring device.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Web 2 Contact thickness profile signal detection means and non-contact thickness profile signal detection means 3 Thickness profile calculation means 11 Thickness measurement upper head 12 Thickness measurement lower head 13 Scan frame 14 Contact thickness profile signal 15 Non-contact thickness Thickness profile signal 16 Thickness profile signal 17 Thickness profile display device 21 Contact type displacement meter 22 Non-contact type displacement meter 23 Air nozzle for web holding 24 Web measuring table 31 Contact type displacement meter measurement trajectory 32 Contact type displacement meter unmeasured range 33 Simultaneous Measurement Range 41 One Example of Contact Thickness Profile 42 One Example of Non-Contact Thickness Profile 43 One Example of Thickness Profile in Contact Measurement Mode 44 One Example of Thickness Profile in Non-Contact Measurement Mode 51 Contact Thickness measurement upper head 52 Contact thickness measurement lower head 61 Non-contact thickness measuring head 62 Measuring guide roll for tensioning web

Continued on the front page F term (reference) 2F063 AA16 AA50 BA30 BB01 BC09 BD18 CA09 DA01 DA02 DA08 DB01 DB05 DD08 EA20 GA08 GA13 KA01 KA05 LA16 LA23 2F065 AA30 AA55 BB24 BB26 CC02 DD03 EE06 EE07 FF55 MM03 Q01 U02 AA47 BB20 BB34 BB40 DD19 EE08 EE22 GG01 GG04 GG52 GG63 HH02 HH09 HH30 JJ06 JJ13 JJ19 NN26 QQ05 QQ07 QQ12 RR01 RR03

Claims (5)

[Claims] Detecting a non-contact thickness profile signal in a width direction of the running web; detecting a contact thickness profile signal; obtaining the obtained non-contact thickness profile signal and the contact thickness profile; A method of measuring a thickness profile, comprising: calculating a thickness profile from a signal; and switching between a contact measurement mode and a non-contact measurement mode. 2. A method of calculating a thickness profile in a contact measurement mode in which a step of detecting a non-contact thickness profile signal and a step of detecting a contact thickness profile signal are always performed simultaneously. 2. The method for measuring a thickness profile according to claim 1, comprising the steps of) to 5). 1) a step of obtaining a difference profile signal from a non-contact thickness profile signal and a contact thickness profile signal of the same section of the web 2) a step of obtaining an average correction amount from the difference profile signal 3) a non-contact in an unmeasured portion of the contact thickness profile Step of correcting the thickness profile signal by the average correction amount obtained in step 2) 4) Combining the corrected non-contact thickness profile signal and the contact thickness profile signal of the corrected unmeasured portion obtained in step 3) 5) a step of repeating steps 1) to 4) 3. A step of calculating a thickness profile in a non-contact measurement mode in which a step of detecting a non-contact thickness profile signal is always performed and a step of detecting a contact thickness profile signal is performed only once. However, the following 1)
The method for measuring a thickness profile according to claim 1, comprising the following steps: 1) a step of obtaining a difference profile signal from the non-contact thickness profile signal and the contact thickness profile signal of the same section of the web 2) a step of obtaining an average correction amount from the difference profile signal 3) the non-contact thickness profile signal of 2) A step of creating a thickness profile signal by correcting with the average correction amount obtained in the step 4) a step of performing steps 1) to 2) at the first measurement at the time of changing the grade 5) a step of constantly performing the step of 3) 4. A non-contact thickness profile signal detecting means in a width direction of a running web, a contact thickness profile signal detecting means, and a thickness obtained from the obtained non-contact thickness profile signal and contact thickness profile signal. A thickness profile measuring device comprising: means for calculating a profile; and means for switching between a contact measurement mode and a non-contact measurement mode. 5. The non-contact thickness profile signal detecting means comprises means for blowing air to hold down the paper, and means for measuring the thickness in a non-contact manner with a laser displacement meter, wherein the contact thickness profile signal detecting means is provided. 5. A thickness profile measuring apparatus according to claim 4, further comprising means for measuring the thickness by contact with an eddy current type displacement meter or a differential transformer type displacement meter.