JP2003336186A - Method and apparatus for measuring paper width - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method and an apparatus for measuring a paper width in which both side end positions of paper traveling in a papermaking machine at a high speed and in high accuracy are measured and the shrinkage and meandering amount of paper traveling can be calculated at the high speed and in high accuracy. <P>SOLUTION: Light sources 3a and 3b and detectors 2a and 2b are arranged in both side end parts of a paper P traveling in the papermaking machine, and light is irradiated from the light sources 3a and 3b toward the paper P and light is caught by the detectors 2a and 2b to measure both side end positions Pa and Pb of the paper P. A data treating apparatus 5 calculates the shrinkage and meandering amount of paper P traveling based on detected signals output from detectors 2a and 2b. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a paper machine for making paper, in which the positions of both ends of the running paper are measured at high speed and with high accuracy, and the amount of shrinkage of the running paper is determined from the deviation of the both ends. The present invention relates to a paper width measuring method and a measuring device for calculating a meandering amount at high speed and with high accuracy.

[0002]

2. Description of the Related Art The paper-making process is a process in which the concentration of pulp liquid is reduced from 1% or less to 90% or more. From another aspect, the water content is reduced from 99% or more to 1% or less. It can be said that this is a dehydration process. More specifically, as shown in FIG. 5, first, the paper making unit 101A of the paper making machine 101 is first described.
In, the pulp liquid is filtered by a wire (mesh) 102 to be dehydrated. Next, in the pressing unit 101B, the wet paper is pressed against the felt (blanket) 103, and is pressed and dehydrated. Finally, in the drying unit 101C, the wet paper is pressed against the metal dryer cylinder 104 heated to high temperature by the steam via the canvas 105, dried and dehydrated.

Here, since the paper has low strength and is easily broken, conventionally, the side end position of the paper is not particularly controlled at the time of papermaking. Nevertheless, the side edge position of the paper falls within a substantially predetermined range, and the paper is normally wound around the spool roll 106 in the winding unit 101D. Also, the paper is
The side end is cut by a high-speed water jet nozzle (nozzle cutter) at the outlet of the paper making unit 101A, and then the water content is gradually reduced, and the transportation speed is set to increase as the water is transported.

As described above, since the paper conveying speed is set to be gradually increased, the paper is pulled and the paper width contracts by several percent. Further, the paper making unit 101A, the pressing unit 101B,
Since there is a slight speed difference between the sections of the drying unit 101C and the speed of each section is controlled by a separate drive unit, the contraction amount of the paper width also changes due to this slight speed change.

Further, the wire 102, the felt 103, and the canvas 105, which convey the paper, are on / off controlled at the side end positions thereof, and the side end positions fluctuate slightly, so that the side of the paper on which the paper travels. The end position is also changed, that is, the paper is meandered.

Further, the wire 102 and the felt 1
It is rare that the 03, the canvas 105, and all the rolls in each section are held horizontally. Normally, the back side on which the drive device and the transmission device are arranged has a heavier weight and is inclined to the back side. Therefore, the center position of the paper is also displaced.

Therefore, the paper width is measured and managed in a state of being wound on the spool roll 106 because of the necessity of satisfying the required size of the paper product, but it is measured immediately at the time of papermaking, that is, in the papermaking process. Not. Very rarely, a B / M meter that scans across the width of the paper to measure the weight of the paper, moisture, etc., or a paper defect detector that is installed across the width of the paper to detect defects such as fine holes and stains is used. Then, the paper width may be measured, but in each case, the paper width is only roughly measured and is not measured with high accuracy.

[0008]

As described above, the paper running in the paper machine contracts in the width direction by several%, and the contraction amount also changes. Further, the running paper slightly meanders, and the mechanical central position of the paper machine and the central position of the paper are deviated from each other. These various factors can have a great impact on the quality of the paper, etc., but in what process does the problem occur when measuring the paper width in the wound state or measuring the paper width roughly? It is difficult to identify and cannot be fundamentally improved.

The present invention has been made in view of the above conventional problems, and measures the positions of both side edges of a paper traveling in a paper machine at high speed and with high accuracy, and travels from the deviation amount of the both side edges. By calculating the amount of paper shrinkage and meandering at high speed and with high accuracy, it becomes easy to identify in which process a problem that affects the quality of the paper occurs, and by correcting the problem, Aims to provide a paper width measuring method and a measuring device capable of improving the quality of paper.

[0010]

In order to achieve the above-mentioned object, the paper width measuring method of the present invention is to irradiate light on both side edges of a paper traveling in a paper machine to measure both side edge positions of the paper,
It is characterized in that the amount of contraction and the amount of meandering of the running paper are calculated from the deviation amounts of the both side edges.

The paper width measuring device of the present invention is a device capable of suitably carrying out the above-mentioned paper width measuring method, and is arranged at both side ends of the paper running in the paper machine, and a light source for irradiating the paper with light. Based on the detectors arranged at both ends of the traveling paper, which capture the light emitted from the light source and measure the positions of both ends of the paper, and the both sides of the paper based on the detection signal output from the detector. And a data processing device for calculating the amount of deviation of the edges and calculating the amount of contraction and the amount of meandering of the paper from the amount of deviation.

Further, in order to prevent the paper from warping at both side ends of the traveling paper, it is preferable to dispose guide members which come into contact with the surface at each side end of the paper.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION A paper width measuring method and apparatus of the present invention will be described below with reference to the drawings. FIG. 1 is an explanatory view showing the paper width measuring method of the present invention, and FIG. 4B is a front view of an embodiment of the paper width measuring apparatus of FIG. 3, FIG. 3B is a side view of FIG. 3A, and FIG. 3B is a side view of another embodiment of the paper width measuring apparatus of the present invention. FIG. 4 is a system diagram showing signal processing of the paper width measuring device of the present invention.

First, the paper width measuring method of the present invention will be described. In FIG. 1, P is a running paper, 1a and 1b are nozzle cutters, and 2a and 2b are detectors. here,
C is the mechanical center position of the paper machine, A is the distance from C to the nozzle cutter 1a, B is the distance from C to the nozzle cutter 1b, D is the distance from C to the reference point of the detector 2a,
E is the distance from C to the reference point of the detector 2b. a is the distance from the reference point of the detector 2a to one side edge of the paper, that is, the deviation amount of one side edge, and b is the distance from the reference point of the detector 2b to the other side edge of the paper, that is, It is the deviation amount of the other side end. It should be noted that a and b are + in the outward direction from the reference point.

Based on the measurement data of a and b, the shrinkage amount of the running paper, the meandering amount, and the variation amount thereof are calculated by the following equations. The center position deviation amount and the meandering amount are + in the direction of one side of the paper. One side end shrinkage A- (D + a) Other side end shrinkage B- (E + b) Full width shrinkage A + B- (D + E)-(a + b) Full width shrinkage variation Δ (a + b) Center position deviation amount {(D + a )-(E + b)-(AB)} / 2 meandering amount (ab) / 2 + (DE) / 2- (AB) / 2 meandering fluctuation amount Δ (ab) / 2

Then, as shown in FIGS. 1 to 3, the light sources 3a and 3b and the detectors 2a and 2b are arranged at both side ends of the paper P traveling in the paper machine, and the side end positions of the paper P are contactless. Measures Pa and Pb at high speed and with high accuracy. After that, FIG.
As shown in FIG. 3, the data processing device 5 calculates the shrinkage amount, the meandering amount, and the fluctuation amount of the traveling paper P in a short cycle by the data processing device 5 through the detection signal processing devices 4a and 4b. Further, the factors of variation are appropriately identified from the frequency variation, and the results are displayed or printed by the data output device 6 to improve the papermaking technique.

As shown in FIG. 2, a method of measuring one side edge and the other side edge of the paper P is as follows. Light sources 3a, 3
b and the detectors 2a and 2b are arranged, the light reflected by the paper P is captured, and each side edge position of the paper P is measured, and
As shown in FIG. 3, the light sources 3a and 3b and the detectors 2a and 2b are arranged on different sides of the upper or lower side of the paper P, and the light shielded by the paper P is captured, and each side edge of the paper P is captured. There is a method to measure the position.

The paper width measuring device 11 of the present invention is a device capable of suitably carrying out the above-described paper width measuring method, and as shown in FIG. Light sources 3a and 3b and detectors 2a and 2b on the same side
Is arranged, light is emitted from the light sources 3a and 3b, and the light reflected by the paper P is captured by the detectors 2a and 2b.
Measure the position of each side edge of. Further, in order to prevent the paper P from warping at each side end portion of the paper P, the guide members 7a and 7b are brought into contact with the upper surface of the paper P, and the side edge of the paper P is removed by removing the influence of external light. Guide members 7a and 7b for clear identification
Black light-shielding plates 8a and 8b are fixed to the lower surface of the.

Instead of the paper width measuring device 11, as shown in FIG. 3, the light sources 3a and 3b and the detectors 2a and 2b are provided on different sides of the upper and lower sides of the paper P at respective side end portions of the paper P.
Is arranged, light is emitted from the light sources 3a and 3b, and the light blocked by the paper P is captured by the detectors 2a and 2b.
The paper width measuring device 21 that measures the position of each side edge of the sheet may be adopted. Further, the guide members 7a and 7b are in contact with the upper surface of the paper P in order to prevent the paper P from warping at the respective side end portions of the paper P.

The detectors 2a and 2b are linear CCDs.
It is preferable to adopt (charge couple device). When a general-purpose linear CCD, for example, with 1,024 pixels and a scan frequency of 20 MHz is used, data is obtained about every 50 μsec in the traveling direction of the paper P, and the resolution in the width direction is in the range of 500 mm. Is about 0.5 mm. Thus, one CCD detector 2a, 2 is provided at each side edge of the paper P.
High-speed and high-accuracy measurement is possible with an inexpensive device configuration in which only b is installed.

As described above, according to the paper width measuring method of the present invention, the positions of both side edges of the traveling paper in the paper machine are measured at high speed and with high accuracy, and the traveling paper shrinks from the deviation amount of the both side edges. Since it is possible to calculate the amount and meandering speed at high speed and with high accuracy, it is possible to immediately identify in which process a problem that affects the quality of the paper occurs, and to correct the problem promptly. Can be improved. And
According to the paper width measuring device of the present invention, the paper width measuring method of the present invention can be suitably implemented.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing a paper width measuring method of the present invention.

2A is a front view of an embodiment of the paper width measuring device of the present invention, and FIG. 2B is a side view thereof.

3A is a front view of another embodiment of the paper width measuring device of the present invention, and FIG. 3B is a side view thereof.

FIG. 4 is a system diagram showing signal processing of the paper width measuring device of the present invention.

FIG. 5 is a schematic configuration diagram of a paper machine.

[Explanation of symbols]

2a, 2b detector 3a, 3b light source P paper Pa, Pb Side edge position of paper 5 Data processing device 7a, 7b guide member

Continued front page    F term (reference) 2F065 AA02 AA03 AA12 AA22 AA23                       AA65 BB13 BB15 CC02 FF04                       JJ05 JJ26 KK01 MM03 QQ13                       QQ24 QQ25 TT03                 3F048 AA00 AB01 AC02 BA07 BA20                       CC05 DA06 DC14                 4L055 CG40 DA09 DA27

Claims (3)

[Claims] 1. A paper machine is irradiated with light on both side edges of the paper to measure the side edge positions of the paper, and the amount of contraction and meandering of the traveling paper is calculated from the deviation of the both side edges. A paper width measuring method characterized in that 2. A light source, which is arranged at both end portions of a traveling paper in a paper machine and emits light toward the paper, and a light source which is arranged at both end portions of the traveling paper and captures light emitted from the light source. Then, based on the detector that measures the positions of both side edges of the paper and the detection signal output from the detector, the deviation amount of the both side edges of the paper is calculated, and the contraction amount and the meandering amount of the paper are calculated from this. And a data processing device for performing the paper width measurement device. 3. The paper width measuring device according to claim 2, wherein guide members that come into contact with the surface of the paper are provided at both ends of the paper that is running in the paper machine.