JPH06207863A - Device for measuring tension profile - Google Patents

Abstract

PURPOSE:To furnish a device for measuring a tension profile in the direction of the width of a web being running, in a noncontact and continuous manner. CONSTITUTION:This device has a noncontact distance-measuring device 4 which measures a distance from one surface of a web 9 by scanning in the direction of the width, air nozzles 8 which blow air against the other surface of the web 9 and a device which executes computation from displacement of the web 9 and an air blowing pressure. A tension profile is monitored continuously during manufacture or processing of the web, and thereby the quality control thereof can be performed rationally.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tension profile measuring device for continuously measuring the tension profile of a running web in a non-contact manner.

[0002]

2. Description of the Related Art When a sheet-like material such as paper or film (hereinafter referred to as a web) is continuously manufactured or processed, or when printing is performed on the web, the tension in the width direction of the running web is not maintained. Uniformity affects the running stability or the winding shape when the web is rolled after being processed. Therefore, it is extremely important to control the uniformity in the production or processing of the web. This is an important issue. Conventionally, as a method of measuring the tension of the web, for example, a web detection support roll having a detector installed between the web support rolls is installed, and the measurement value obtained by the detector is sent to the tension indicator to measure the entire web. There is a method of calculating the tension of and measuring.

A conventional tension measuring device is specifically as shown in the basic configuration diagram of FIG. The web 11 passes under the web support roll 12,
The web detection support roll 13 is passed from above the other web support roll 12, and the data obtained by the detector 14 attached to the web detection support roll 13 is displayed on the tension indicator (not shown). No.) to measure the tension of the entire web.

[0004] In such a prior art, it is possible to measure the tension (draw) of the entire web while it is running, but it is not possible to measure the tension profile in the width direction of the web, and thus the production of the web. Or, it was insufficient for controlling the running stability in processing and the winding appearance when finished in winding. Further, since the web and the web detection supporting roll are in contact with each other and the contact type tension measuring method is used, the surface of the web is deteriorated, which is not preferable in terms of quality control.

Further, when factors such as basis weight, water content, texture, coating amount, etc. are given by the coating of the web itself or on the web in the width direction of the web, the factors are accompanied by the factors. Although the tension profile of the web also varies, it has been difficult to measure this tension profile with the conventional technology.

[0006]

In the above-mentioned prior art, it was difficult to accurately measure the tension (draw) of the web in a non-contact manner when the web was manufactured or processed continuously. An object of the present invention is to provide a tension profile measuring device capable of continuously measuring a tension profile of a running web, which has not been obtained by the conventional technique, in a non-contact manner.

[0007]

According to the present invention, air pressure is applied to a running web in a non-contact manner, the web is scanned in the width direction, and a tension profile is easily detected by a non-contact detector. It can be measured accurately. That is, the tension profile measuring device of the present invention is a non-contact distance measuring device that measures the distance from the surface of a running web by scanning in the width direction of the web, and an air pressure control unit on the back side of the web. An air nozzle provided, a device for calculating from the displacement of the web measured by the distance measuring device and the blowing pressure of air are equipped, and the tension profile in the width direction of the web is measured.

In the tension profile measuring device of the present invention, the distance measuring device is a laser displacement meter.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A tension profile measuring device of the present invention will be described below with reference to the drawings.

FIG. 1 is a basic configuration diagram of a tension profile measuring device of the present invention. On the lower surface of the web 9 running in the horizontal direction, an air introduction pipe 6 for introducing air from the air pressure control unit 5 and a plurality of air nozzles 8 for blowing the introduced air to a portion of the air introduction pipe parallel to the web are attached. ing. An air pressure measuring device 7 is attached to the end of the air introducing pipe 6. The web 9 is supported by two web support rolls 1. On the upper surface of the web, there is a scanning unit 2 capable of moving a distance measuring device 4 for measuring the distance from the web surface in the width direction of the web. A position measuring device 3 for measuring the position of the distance measuring device 4 is attached to the end of the scanning unit 2.

FIG. 2 is a side view of the tension profile measuring apparatus of the present invention in the tension measuring apparatus for the web surface during the paper manufacturing process. A plurality of air nozzles 8 are attached to the air introduction pipe 6 on the lower surface of the web 9. The web 9 is the air 10 from the air nozzle 8.
Is being sprayed. A distance measuring device 4 and a scanning unit 2 capable of moving the distance measuring device 4 are provided on the upper surface of the web 9 in a non-contact state, and the distance measuring device 4 measures the distance from the surface of the web 9.

As shown in FIG. 2, the air nozzle 8
Is attached to the air introduction pipe 6 and blows the air 10 onto the test surface, that is, the lower surface of the web 9 during the manufacturing process.

The air nozzle 8 must always supply a constant pressure to the web 9. Therefore, the air pressure control unit 5 controls the fluctuation of the air pressure to be small. Further, by reducing the clearance between the air nozzle 8 and the web 9, the influence of the adjacent air nozzles is eliminated and accurate measurement becomes possible. By making the air blown out from the air nozzle 8 thin, the measured tension profile value becomes stable.

On the other hand, it is necessary to change the air pressure depending on the basis weight of the web 9 to be manufactured. If the basis weight is small,
Lower the air pressure and raise it if the basis weight is large.

A laser displacement meter is used as the distance measuring device 4,
The laser displacement meter is attached to the scanning unit 2 with the light emitting unit facing the test surface, that is, the upper surface of the web. The scanning device corresponding to the scanning unit 2 detects the position of the laser displacement meter by an attached encoder (not shown).

In the apparatus constructed as described above, air is blown perpendicularly to the web 9 from the air nozzle 8 and the change in the web 9 due to the air pressure is measured by a laser displacement meter. This measurement data is sent to the attached computer, the displacement amount and the tension profile value are calculated by the computer, and the curve tension profile as shown in FIG. 4A is displayed.

When the basis weight of the web 9 to be measured is small, the displayed image is a scaled-out image as shown in FIG. In such a case, it is necessary to weaken the air pressure. Conversely, if the basis weight is large,
The displayed image is an image with small fluctuation as shown in FIG. In such a case, an appropriate tension profile curve can be obtained by increasing the air pressure.

[0018]

As described above, according to the tension profile measuring device of the present invention, the tension profile in the width direction of the running web can be accurately and easily measured regardless of the basis weight. This makes it possible to reasonably perform running stability and quality control of a continuously manufactured or processed web.

[Brief description of drawings]

FIG. 1 is a basic configuration diagram of a tension profile measuring device of the present invention.

FIG. 2 is a side view of the tension measuring device for a web surface during a paper manufacturing process, which is an embodiment using the tension profile measuring device of the present invention.

FIG. 3 is a basic configuration diagram of a conventional tension measuring device.

FIG. 4 is a typical tension profile obtained by using the tension profile measuring device of the present invention.

[Explanation of symbols]

 1, 12 Web supporting roll 2 Scanning unit 3 Position measuring device 4 Distance measuring device 5 Air pressure control unit 6 Air introducing pipe 7 Air pressure measuring device 8 Air nozzle 9, 11 Web 10 Air 13 Web detecting supporting roll 14 Detector

Claims (2)

[Claims] 1. A tension profile measuring device, a non-contact distance measuring device for measuring a distance from a front surface of a running web by scanning in a width direction of the web, and an air pressure control unit on a back surface side of the web. A tension profile measuring device equipped with an air nozzle provided and a device that calculates from the displacement of the web measured by the distance measuring device and the air blowing pressure, and measures the tension profile in the width direction of the web. . 2. The tension profile measuring device according to claim 1, wherein the distance measuring device is a laser displacement meter.