JP2003214839A - Device for analyzing and alarming sheet width fluctuation - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a device for analyzing and alarming sheet width fluctuation that can analyze a data concerning the fluctuation of sheet width and provide an operator with estimated fluctuation factors based on the analyzed result as a maintenance information of a process device and a quality information of a product. <P>SOLUTION: The device is provided with a Fourier analysis means in which being input a sampled signal of a sheet end fluctuation signal from a reference position at both ends of a sheet to be conveyed by a rotary body means and obtains the frequency characteristic of the sheet end fluctuation at a specified cycle, a synchrony judging means using a correlation between a frequency giving a maximum sheet end fluctuation by the frequency characteristic and the rotating frequency of the rotary body, and a meandering alarming means that alarms meandering of the sheet when the synchrony is within a specified value. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention analyzes paper width fluctuation data of sheets conveyed by a rotating means, mainly paper produced by a coating machine and a paper machine process in the paper manufacturing industry, and is assumed based on the analysis result. It is intended to provide process equipment maintenance information and product quality information regarding a device that alerts the operator of the fluctuation factors.

[0002]

2. Description of the Related Art A technique for measuring the edge variation (sheet width, meandering) of a sheet material with high speed and high accuracy by means of CCD camera means is disclosed, for example, in Japanese Patent Laid-Open No. 2000-9435. Figure 3
B / used to measure the basis weight and moisture content used in the papermaking process
It is a configuration example in which a paper edge variation sensor is fixed to an M meter frame.

Reference numeral 1 denotes a paper to be detected, which is shown in a cross section in the width direction, and is conveyed in a direction orthogonal to the paper surface by a rotating means (not shown). 2 is B / which scans the paper 1 periodically in the width direction B /
M meter sensor, 3 is a B / M meter frame, and 4 is a guide which is supported by the B / M meter frame and slides the B / M meter sensor 2.

Numerals 5 and 6 are paper edge fluctuation sensors fixed to the B / M meter frame 3 so as to face each other at both ends of the paper 1. The paper edge variation sensor 5 transmits a distance detection signal Ef of the distance Lf between the one end f of the paper 1 and the reference point S1 on the f side. Similarly, the paper edge variation sensor 6 is provided at the other end b of the paper 1.
The distance detection signal Eb of the distance Lb between the point and the reference point S2 on the point b side is transmitted. L is a distance between the reference points S1 and S2 and is a fixed value.

The width variation and meandering amount of the paper 1 can be detected by the distance detection signals Ef and Eb of the paper edge portion having such a configuration. These data are included in the B / M meter sensor basis weight and water content data. , Used as measurement data for papermaking process control.

[0006]

For example, when the amount of meandering or the contraction rate exceeds a predetermined set value, it is necessary to identify the cause of the abnormality and take a countermeasure. If the cause of the abnormality is the rotating body means such as rolls and felts that are used in large numbers in the papermaking process, maintenance is necessary for safe operation, but there is a problem only with paper width fluctuation data. It is impossible to identify the rotating body means.

The following data processing is required to identify such a factor. (1) The paper width is measured with an accuracy of 1 mm or less and at a high speed of tens of milliseconds or less. (2) The following analysis is performed at high speed using the measured data. Calculation of meandering amount and its cycle Paper contraction rate and its cycle (3) The calculation result is transmitted to the existing system such as B / M meter,
Display data in a format that is easy for operators to monitor and manage. (4) A threshold function is added to the calculated data, and an alarm is generated when the calculated data exceeds the allowable range to alert the operator and provide coping measures.

An object of the present invention is to analyze the width variation data of a sheet, and to provide a variation factor assumed based on the analysis result to the operator as maintenance information of process equipment and quality information of the product to the operator. It is in the provision of analysis and alarm devices.

[0009]

In order to achieve such an object, the feature of the invention as set forth in claim 1 of the present invention is that the both end portions of the sheet conveyed by the rotator means are separated from the reference position. A sheet edge fluctuation signal is input as a sample, and Fourier analysis means for obtaining the frequency characteristic of the sheet edge fluctuation in a predetermined cycle, and a correlation based on the frequency that gives the maximum sheet edge fluctuation with the frequency characteristic and the rotation frequency of the rotating body are obtained. It is provided with a synchronism judging means for judging and a meandering alarm means for warning the occurrence of meandering of the sheet material when the synchronism is other than a predetermined value.

According to a second aspect of the present invention, a pair of Fourier analysis means for inputting a sheet edge variation signal from a reference position at both ends of the sheet material as a sample and obtaining a frequency characteristic of the sheet edge variation at a predetermined cycle. And the data collating means for collating the analysis results of these Fourier analyzing means and adopting the matched data at a predetermined set value or more as the normal sheet edge variation data.

The third aspect of the present invention is characterized in that the maximum value of the sheet edge variation data collated by the data collating means is displayed as a meandering amount.

According to a fourth aspect of the present invention, there is provided a sheet width calculating means for adding a sheet end variation signal from a reference position and a fixed width signal at both ends of the sheet conveyed by the rotating means, and the sheet. Fourier analysis means for inputting the output of the width calculation means to obtain the frequency characteristic of the sheet width variation at a predetermined cycle, and determining the correlation based on the frequency giving the maximum variation of the frequency characteristic and the rotation frequency of the rotating body And a sheet width alarm means for giving a warning of occurrence of sheet width variation when the synchronism is other than a predetermined value.

A fifth aspect of the present invention is that the maximum value of the data calculated by the sheet width calculating means is displayed as the sheet width variation amount.

According to a sixth aspect of the present invention, the shrinkage rate is calculated based on the data calculated by the sheet width calculation means and the preset reference sheet width data, and the shrinkage rate is set in advance. The point is that an abnormal contraction alarm means for issuing an alarm when the value is exceeded is provided.

A seventh aspect of the present invention is that the calculation result data of the shrinkage ratio is displayed as a sheet width shrinkage ratio variation amount.

A feature of the present invention is that the sheet material is paper in a papermaking process, and a sensor for outputting the sheet edge variation signal is fixed to a B / M meter frame of the papermaking process. .

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a functional block diagram showing an example of a sheet width variation analysis / alarm device to which the present invention is applied. As a sheet object, the sheet 1 described in FIG. 3 is targeted, and the distance detection signals Ef and Eb at the edge of the sheet are detected. Input and analyze.

Reference numeral 7 is a high-speed real-time input processing unit,
The distance detection signals Ef and Eb are read at high speed. Reference numerals 8 and 9 denote first and second Fourier analysis units, which perform a Fourier analysis by inputting sampled data d1 and d2 at each timing when a preset number of signals are stocked in the input processing unit 7. The fluctuation amount and fluctuation period of are calculated.

Generally, the Fourier analysis is an analysis function for decomposing an input signal into signal components for each fluctuating frequency by using the theory of Fourier series. With this function, the fluctuation amount for each frequency can be analyzed, and the maximum fluctuation It is used for analysis such as detecting the frequency band in which the quantity occurs.

Reference numeral 10 is a data collating unit for the purpose of avoiding a measurement error and a calculation error, and collates the Fourier analysis results g1 and g2 of the distance detection signals Ef and Eb and frequency data of the maximum fluctuation amount calculated by both. Check if the value is greater than or equal to the preset value, and if the match is greater than the set value, use normal data.

Reference numeral 11 denotes a meandering frequency calculation & display section, which uses the verified data to create a meandering frequency graph of the horizontal axis frequency f and the vertical axis variation amount d shown in FIG. In addition, the cursor is displayed on the frequency f0 part corresponding to the maximum fluctuation amount,
Specify the location of the maximum fluctuating frequency.

Reference numeral 12 is a first synchronism confirmation unit, which uses the roll circumference determined by the diameter data for each rotor member of the paper machine such as rolls and felts and the current machine speed R which are stored in a database in advance. The frequency fr of the corresponding rotating body means is calculated by the following equation. Rotor frequency fr = (machine speed Rm / sec) / (roll circumference) _i i: number of each rotor means

The correlation between the calculated value fr and the calculated frequency f0 that gives the maximum fluctuation is estimated for each rotating means. The correlation is most easily estimated by determining how close the ratio of f0 to fr is to "1". For example, if it is 0.90 or more, it is estimated that there is a correlation.

Reference numeral 13 denotes a first alarm processing unit, which operates for each rotating body means when the coincidence between the calculation result of the rotating body frequency fr and the frequency f0 giving the maximum fluctuation is equal to or more than a preset value. "Merking caused by XXX rolls"
Raise an alarm.

Reference numeral 14 denotes a meandering width calculation & display unit, which displays the maximum fluctuation amount of the data collated by the data collating unit 10 as a meandering amount by a digital numerical value. This display is independent of the function of the first alarm processing unit 13, and displays the maximum fluctuation amount regardless of whether an alarm is generated due to frequency matching.

Reference numeral 15 denotes a second alarm processing unit, which indicates to the operator if the meandering amount displayed at 14 is a preset value or more, even if the frequencies do not match, the operator is instructed to "meander.
Raise an alarm.

A paper width calculation & display unit 16 calculates the paper width w as follows using the data d1 and d2 and the data of the fixed distance L obtained from the input processing unit 7 and displays it on the screen as a digital value. To do. Paper width w = L + Lf + Lb

Reference numeral 17 denotes a third Fourier analysis unit, which performs Fourier analysis at each timing when the paper width data w calculated by a preset quantity is sampled and input.
The fluctuation amount and fluctuation period of the paper width are calculated.

Reference numeral 18 denotes a paper width fluctuation frequency calculation & display unit, which uses the Fourier analysis result h to create a paper width fluctuation frequency graph of the horizontal axis frequency f and the vertical axis paper width fluctuation amount similar to FIG. Further, a cursor is displayed on the frequency f0 portion corresponding to the maximum fluctuation amount to clearly indicate the location of the maximum fluctuation frequency.

Reference numeral 19 is a second synchronism confirmation unit, which uses the roll circumference determined by the diameter data data for each rotor member of the paper machine such as rolls and felts and the current machine speed R, which are stored in the database in advance. Then, the frequency fr of the corresponding rotating body is calculated by the following equation. Rotor frequency fr = (machine speed Rm / sec) / (roll circumference) _i i: number of each rotor means

The correlation between the calculated value fr and the calculated frequency f0 that gives the maximum fluctuation is estimated for each rotating means. The correlation is most easily estimated by determining how close the ratio of f0 to fr is to "1". For example, if it is 0.90 or more, it is estimated that there is a correlation.

Reference numeral 20 denotes a third alarm processing unit, which operates for each rotating body means when the coincidence between the calculation result of the rotating body frequency fr and the frequency f0 giving the maximum fluctuation is equal to or more than a preset value. Then, the alarm "Paper width fluctuation occurs due to XXX roll" is issued.

Reference numeral 21 denotes a shrinkage rate calculation & display section, which performs the following shrinkage rate calculation using a preset reference paper width value and displays the data in digital values. Shrinkage rate (%) = [1- (calculated paper width data) / (reference paper width data)] * 100

Reference numeral 22 denotes a fourth alarm processing section, which issues an alarm "abnormal contraction occurs, caution" to the operator when the contraction rate displayed at 21 exceeds the preset upper and lower limit values.

Although the embodiments described above are intended for paper in a papermaking process, the present invention can be applied to various purposes as long as it is a sheet material such as a film or a plate material conveyed by a rotating means. .

Although the present invention has been described as an apparatus for management independent of the process control, it may be incorporated as one function of the process control system, and the display and alarm may be shared with the man-machine interface of the control apparatus. It is possible.

[0037]

As is apparent from the above description,
According to the present invention, the following effects can be expected. (1) Since the operation management can be performed so as to obtain the paper width that conforms to the product standard by obtaining the accurately measured paper width data, there is no waste as a margin, which directly leads to cost reduction. (2) By monitoring the change in shrinkage ratio in real time, the process status of the drying process can be monitored and monitored, which enables efficient operation, reduces operating costs, and contributes to stable quality.

(3) Further, the alarm function can detect and take care of a process abnormality that greatly hinders the operation, which greatly contributes to the improvement of the operation rate of the operation. (4) Since the condition of the tools used in the paper machine can be monitored from the meandering cycle, the life of the tools can be managed and the operating cost can be reduced.

(5) Similarly, from the meandering cycle, it is possible to confirm the proper operating condition of the drive unit, tools such as rolls used in the paper machine, and it is possible to discover a device failure that greatly impairs the operation. , And can contribute to the improvement of operating rate.

[Brief description of drawings]

FIG. 1 is a functional block diagram showing an example of a sheet width variation analysis / warning apparatus to which the present invention is applied.

FIG. 2 is a meandering frequency graph of a horizontal axis frequency f and a vertical axis variation amount d.

FIG. 3 is a configuration diagram showing an example of a fluctuation detection mechanism in which a paper edge fluctuation sensor is fixed to a B / M meter frame used in a papermaking process.

[Explanation of symbols]

7 Input processing unit 8 First Fourier transform unit 9 Second Fourier transform unit 10 Data collation section 11 Meander frequency calculation & display 12 1st synchronization confirmation part 13 First alarm processing unit 14 Meandering amplitude calculation & display 15 Second alarm processing unit 16 Paper width calculation & display 17 Third Fourier Transform Unit 18 Paper width fluctuation frequency calculation & display 19 Second synchronization check part 20 Third alarm processing unit 21 Shrinkage rate calculation & display 22 4th alarm processing unit

Claims (8)

[Claims] 1. A Fourier analysis unit for inputting a sample end edge variation signal from a reference position at both ends of a sheet conveyed by a rotator means and obtaining a frequency characteristic of the sheet edge variation at a predetermined cycle, A synchronism determination means for determining a correlation based on a frequency that gives the maximum sheet edge variation in the frequency characteristic and a rotation frequency of the rotating body, and when the synchronism is other than a predetermined value, warns the occurrence of a meandering sheet A sheet width variation analysis / warning device comprising a meandering alarm means. 2. A pair of Fourier analysis means for sample-inputting a sheet end variation signal from a reference position at both ends of the sheet material to obtain a frequency characteristic of the sheet edge variation at a predetermined cycle, and a pair of Fourier analysis means of these Fourier analysis means. 2. The sheet width variation analysis / warning apparatus according to claim 1, further comprising: a data collating unit that collates the analysis results and adopts data that is equal to or more than a predetermined set value as regular sheet edge variation data. 3. The sheet width variation analyzing / warning device according to claim 2, wherein the maximum value of the sheet edge variation data collated by the data collating means is displayed as a meandering amount. 4. A sheet width calculating means for adding a sheet edge fluctuation signal from a reference position and a fixed width signal at both ends of a sheet conveyed by a rotating means, and a sample of the output of the sheet width calculating means. Fourier analysis means for inputting and determining the frequency characteristic of the sheet width variation at a predetermined cycle, and synchronism determination means for determining correlation based on the frequency giving the maximum variation of the frequency characteristic and the rotation frequency of the rotating body, A sheet width variation analyzing / warning apparatus, comprising: a sheet width alarm unit that warns the occurrence of sheet width variation when the synchronism is other than a predetermined value. 5. The sheet width variation analysis / warning apparatus according to claim 4, wherein the maximum value of the data calculated by the sheet width calculation means is displayed as a sheet width variation amount. 6. A shrinkage rate is calculated based on the data calculated by the sheet width calculation means and preset reference sheet width data, and an alarm is issued when the shrinkage rate exceeds preset upper and lower limit values. The sheet width variation analysis / warning device according to claim 4 or 5, further comprising abnormal contraction alarm means for generating the following. 7. The sheet width variation analysis / warning apparatus according to claim 4, wherein the shrinkage rate calculation result data is displayed as a sheet width shrinkage rate variation amount. 8. The sheet according to claim 1, wherein the sheet material is a paper in a papermaking process, and a sensor for outputting the sheet edge fluctuation signal is fixed to a B / M meter frame of the papermaking process. Sheet width variation analysis / warning device.