JP2797474B2 - Formation measurement method and formation control method using the formation measurement method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention grasps unevenness of transmitted light of paper as a planar image,
The present invention relates to a formation measurement method that can evaluate the properties and quality of paper and can be used as control means for improving the quality, and a formation control method using the formation measurement method.

[Prior art] The quality of paper formation (small thickness unevenness) means the degree of dispersion of fibers in a sheet. Generally, a sample sheet is placed on an inspection box with a built-in light source. ,
The transparency analysis has been performed by visual inspection.

Although this method is widely practiced at each factory, it is probably subjective and its judgment requires sufficient knowledge and long experience, so that there is an individual difference in the test results.

For this reason, conventionally, the ground total as shown in FIG. 11 has been devised and actually used, and the vertical head is placed at the vertical position of the running paper a for which the formation is to be measured so as to sandwich the paper a. b,
c, a light source d such as a laser connected to a power supply, and a mirror f for irradiating light e from the light source d to the paper a in the lower head c. And a photocell j that receives light e passing through the paper a via a mirror g, a filter h, and a lens i.

Thus, the light e emitted from the light source d is applied to the paper a via the mirror f, and the light e transmitted through the paper a is incident on the photocell j via the mirror g, the filter h, and the lens i, and the voltage e is applied. The voltage value is displayed as a formation index with respect to time as shown in FIG.

In addition, when the formation index is measured, a person judges based on the formation index and appropriately changes the jet wire ratio (J / W ratio) and the like so that the formation is good. .

[Problems to be Solved by the Invention] However, in the above-described total, the light source d
Since the diameter of the light e irradiated from the paper a to the paper a is about 1 mm, and the transmitted light signal is processed one-dimensionally, the fluctuation of the transmitted light level is captured as the floc size. Although formation was quantified, the judgment sample was too small to make an overall judgment as judged by human vision, and had the drawback that formation could not be captured accurately. .

Also, with regard to the formation control, the J / W ratio is only adjusted by trial and error, and the control is based on the measurement result that does not grasp the entirety of the ground total. It has not been possible to easily improve the quality of the product.

In view of such circumstances, the present invention provides a formation measurement method capable of objectively evaluating the formation as a surface rather than as a point, and a paper quality improvement method based on the detection result by the formation measurement method. An object of the present invention is to provide a formation control method that can be performed efficiently.

Means for Solving the Problems The present invention captures an image of light emitted from a strobe and transmitted through a sheet of paper of a required area with a camera, and displays the image as a transmitted light image on a display device of an arithmetic processing unit for image processing. The transmitted light image projected on the window is divided into a required size and a required number of windows, and the average value of the density of each window and the primary variance of the density of each window are calculated from the densities of the pixels existing in each window. Further, the average value of the primary variance of the concentration of the entire window, the variance of the average value of the concentration of each window, and the secondary variance of the concentration of the entire window are calculated, and 1 of the concentration of the entire window is calculated. One of the average value of the secondary variance, the variance of the average value of the density of each window, and the secondary variance of the density of the entire window, or a combination of two or more of them is used as the formation coefficient. The method is based on experimental data obtained in advance, and specifies the quality of the paper in multiple stages from the worst to the best based on the degree to which the paper formation coefficient is applied to the paper formation coefficient. For each change in J / W ratio, foil angle, and deflector indentation amount corresponding to each of the plurality of membership function curves for determining the paper quality and the membership function curves for specifying the quality of the paper. A plurality of control membership function curves indicating the degrees are obtained in advance, and at each intersection of the formation coefficient measured by the formation measurement method and each membership function curve for specifying the quality of the paper. First, the degree of matching in the J / W ratio is determined from the respective membership function curves for control indicating the J / W ratio change in accordance with the degree of each matching, and the inference result of each J / W ratio change is obtained. The J A final membership function indicating the final inference result of the J / W ratio change amount synthesized by superimposing the respective inference results of the / W ratio change amount is obtained, and the actual J / W ratio of the J / W ratio is determined based on the final membership function. Determine the amount of change and control the J / W ratio,
This was repeated until the formation coefficient was not reduced by the change in the W ratio, and the formation angle was then determined and controlled in the same manner for the foil angle and the deflector indentation amount. The present invention also relates to a formation control method. In addition, in the repetition of the control by the formation control method, the control member is determined based on the sign of the difference between the formation coefficient of the previous control and the formation coefficient of the current control. The present invention relates to a formation control method characterized in that a ship function is selected. In addition, at the time of starting measurement, a field of view of a camera is enlarged to observe the entire formation, and control by the formation control method is started. According to the formation control method, the field of view of the camera is gradually reduced as the formation of the rear is improved, and when the formation is stabilized and the control is almost completed, the camera returns to the original large field of view and enters the monitoring state. thing In addition, a plurality of cameras are arranged at different distances from the paper, and when the measurement is started by switching the plurality of cameras, the entire formation is observed with the camera having the largest field of view, and the control by the formation control method is started. As the rear formation improves, the camera is sequentially switched to a camera having a smaller field of view, and when the formation is stabilized and the control is almost completed, the camera is switched to a camera having a larger field of view to be in a monitoring state. In the formation control method, the formation of the transmitted light image is subjected to frequency analysis in the width direction to determine whether the formation is pulling formation or pushing formation. / W ratio is increased while J / W
The present invention relates to a formation control method characterized in that control is performed by decreasing the ratio.

[Operation] Accordingly, in the formation measurement method of the present invention, an image of light emitted from a strobe and transmitted through a sheet of paper of a required area is captured by a camera and transmitted to a display device of an arithmetic unit for image processing as a transmitted light image. At the same time, the transmitted light image projected on the display device is divided into a required size and a required number of windows, and from each density of the pixels present in each window, the average value of the density of each window and the density of each window are displayed. Concentration 1
The secondary variance is calculated, and further, the average value of the primary variance of the density of the entire window, the variance of the average value of the density of each window, and the secondary variance of the density of the entire window are calculated. , The variance of the average value of the density of each window, and any one of the secondary variances, or a combination of two or more of them, is obtained as the formation coefficient, and the formation is more accurately quantified. .

Further, in the formation control method using the formation measurement method of the present invention, the quality of the paper in a plurality of stages from the worst to the best based on experimental data obtained in advance is determined with respect to the formation coefficient of the paper. A plurality of membership function curves for specifying from the degree to which they apply, and the J / W ratio, foil angle,
And a plurality of control membership function curves indicating the degree of application of each change amount of the deflector depression amount are obtained in advance, and the formation coefficient measured by the formation measurement method and the quality of the paper are specified. The degree of matching at each intersection with each membership function curve of
First, each J / W is obtained from each control membership function curve showing the J / W ratio change amount in accordance with the degree of each matching.
The inference result of the ratio change amount is obtained, and the final membership function indicating the final inference result of the J / W ratio change amount synthesized by superimposing the respective inference results of the J / W ratio change amount is obtained,
The actual amount of change in the J / W ratio is determined based on the final membership function, the J / W ratio is controlled, and this is repeated until no decrease in the formation coefficient due to the J / W ratio change is observed. Hereinafter, similarly, the change amounts of the foil angle and the deflector pressing amount are sequentially determined and controlled, and the formation is improved.

Further, in the repetition of the control by the formation control method, if the control membership function is selected based on the sign of the difference between the formation coefficient at the time of the previous control and the formation coefficient at the time of the current control, the efficiency can be further improved. Good control can be performed.

Furthermore, at the start of measurement before performing the control by the formation control method, the field of view of the camera is enlarged to observe the entire formation, and as the formation is improved after the start of the control, the field of view of the camera is gradually reduced. By reducing the size, it helps to control the formation finely, and after the formation is stabilized and the control is almost completed,
If the field of view of the camera is enlarged to the original state and the monitoring state is set, it is possible to cope with external changes such as changes in raw material conditions.

Further, if a plurality of cameras having different visual fields, that is, different distances from the paper are installed instead of changing the visual field of one camera as described above, it is not necessary to perform the movement for changing the visual field of the camera. The field of view of the camera can be changed more quickly by switching only a plurality of cameras.

Further, in the control by the formation control method, if the density of the transmitted light image is subjected to frequency analysis in the width direction, it is possible to easily determine whether the formation is pulling formation or pushing formation.
If the control is performed while increasing the J / W ratio while decreasing the J / W ratio in the case of the pushing formation, reliable and efficient control can be performed.

[Example] Hereinafter, an example of the present invention will be described with reference to the drawings.

FIGS. 1, 3 and 4 show an embodiment of the present invention, in which a strobe box 2a having a built-in strobe 2 is arranged on one side of a paper 1 to be inspected, and a camera box 3a is mounted on the opposite side with respect to a rail 3c. 1, a camera 3 having a zoom function and a variable aperture device 3b is arranged in the camera box 3a. As the camera 3 of the present embodiment used together with the strobe 2, a CCD (Cha
(rge Couple Device) A frame accumulation mode camera or a camera having a function similar to the camera is used. The camera 3 is connected via a cable 4 to an arithmetic unit for image processing 5 having a display device 6. Further, a separate display device 7 is connected to the camera 3 via a cable 8 in order to always display an actual transmitted light image of the paper 1.

The control computer 100 and the control controller 1
01 is provided for control, and the arithmetic unit 5 for image processing and the control computer 100 are connected to the formation signal line 102 and the control signal line 103.
And a control computer 100 and a control controller 101 are connected by a communication line 104. Further, the control controller 101 has a jet speed and a bottom wire 12 which are jetted from a head box 10 shown in FIG. An actuator for changing the ratio of the top wire 16 to the wire speed, an actuator for changing the angle of the foil 14, and the like are connected by a control signal line 105.

Since the paper 1 to be inspected is actually quite large, the portion to be taken out as a sample (10 mm × 10 mm or more) is the entire paper 1 if only the portion is viewed without missing the characteristics of the paper 1. Area (area that can be regarded as steady).

At the time of measurement, the aperture of the camera 3 is set in advance by a variable aperture device 3b so as to be optimal according to the thickness of the paper 1,
Adjustment is made so that an appropriate amount of transmitted light is obtained from the strobe 2. The signal entering the camera 3 enters the display device 7 and is always displayed as an image 9a of the actual transmitted light of the paper 1, while the signal entering the image processing operation device 5 is formed as shown in FIG. Is displayed on the display device 6 as an image 9 showing an area in which the quality of the whole paper 1 can be determined. Displayed darker (darker) than average.

Subsequently, windows W ₁ , W ₂ ,..., In which a region having an average size of a hole or the like or an area approximately twice as large as a minimum size of a floc peculiar to paper in the image 9 are set as dispersion calculation units. W _k ,…, W _N
(See FIG. 3 (b)). The size and number of the windows can be appropriately selected depending on the type of paper, the composition, and the like.

Here, as shown in FIG. 4, M = n × m pixels (n = 4, m in the example of the figure) of the display device 6 in one window.
= 5) When it is included, since the density of each pixel in the i-th row and the j-th column in the k-th window W _k is represented by C _kij , k
Th of the average value of _C avk in concentration within the window W _k And a variance V _avk (hereinafter referred to as first-order variance) of the concentration in the k-th window W _k .
That is, a value that is a measure of how much the density varies within one window W _k is: (See FIG. 3 (c)).

Furthermore, the window _{W 1, W 2, ...,} W k, ..., the average value a _v of the primary dispersion of the entire W _N More calculated on the basis of the average value a _v of the primary dispersion of該全body, the window _{W 1, W 2, ...,} W k, ..., dispersion of the primary dispersion of the entire W _N V _av (hereinafter 2 Secondary dispersion), and the window W ₁ ,
The variance V _aav of the average value C _avk in W ₂ ,…, W _k ,…, W _N And the result of the calculation is displayed (see FIG. 3 (d)).

Mean a _v of the primary dispersion as the whole window as (texture coefficient when there is a non-uniform paper for example large defect) formation factor in a relatively wide field of view is intended to display a macroscopic dispersion of the screen The formation is quantified, and the variance of the average density of each window, V _aav , represents the macroscopic dispersion of light and dark with respect to the average density of the screen. The formation is quantified as a coefficient, and furthermore, in the evaluation at the final stage of the control in which the whole paper is determined to be uniform and micro formation, the variance of the primary variance of the window as a whole (secondary variance) The formation is quantified using V _av as the formation coefficient.

It goes without saying that formation of a formation is quantified using a combination of a _v , V _aav , and V _av as a formation coefficient depending on an object.

Also, as shown in FIG.
Next, the pixels in the columns a ₁ to an in the b _{i -th} stage of the pixels constituting the image 9 projected on the display device 6 or b _{1 in the} column a _i
A data logger (not shown) that accumulates the density data of the pixels of the 〜b to _n stages, and an analyzer (not shown) that extracts the data accumulated in the data logger, captures the data as time-dependent change data, and analyzes the data with frequency. And the data stored in the data logger is processed by analysis software, and it is determined whether or not a pulsating component exists in the paper 1 based on the frequency analysis result in the vertical direction (the longitudinal direction of the paper 1). It is also possible. Also, the frequency analysis in the horizontal direction (longitudinal direction of the paper 1) uses a strobe 2 as compared with the conventional case in which the transmitted light is captured at a spot, so it corresponds to a floc that faithfully reproduces the density of the formation. Can be expressed,
It is easy to determine whether the formation is a pull formation or a push formation. The pulling formation refers to a state in which the flock is stretched in a streak shape, and the pushing formation refers to a state in which the flock has a scaly shape. Here, when the average value of the concentration is plotted on the vertical axis and the frequency is plotted on the horizontal axis, the ideal formation is shown as a two-dot chain line in FIG. Each case is shown as a broken line.

In this way, the formation can be quantified as a surface rather than as a point as in the past, and it can be objectively evaluated with higher accuracy.Furthermore, based on the formation coefficient, the J / W ratio, dehydration amount control, etc. Can be used.

Since the formation measurement method described above uses the strobe light 2 as a light source, it can be applied to not only offline conditions but also online conditions of high speed (about 1500 m / min per ^second ) and high weighing (about 300 g / m ² basis weight).

 The advantage of using a strobe as a light source is that there is little screen shift during high-speed online measurement.

For example, comparing the shutter speed and the flash light time of the strobe when shooting with a parallel light source and camera shuttering together, the flash light time of the strobe is about 1 /
Since the value is 10, the use of a strobe reduces the displacement of the screen at high speed, and the displacement of the screen does not hinder the analysis of the pixels on the screen.

When the camera is shuttered, it is possible to cope with the analysis of a ternary image representing the density in three stages, for example, “dark”, “medium”, and “light” in order to further clarify the image. However, the combination of a strobe and a non-shuttering camera is more suitable for high-speed photographing for detecting shades.

Comparing a collimated light source with a strobe (pulse light source), a strobe can easily obtain a larger amount of light. (A) The aperture of the camera can be reduced during shooting, and the effect of disturbance can be reduced.

 (B) Thick paper can be easily transmitted.

Even with camera shuttering, there is a limit to the speed of current mechanical shuttering, but when using electric shuttering that electrically shutters the camera's field of view, a combination of strobe and shuttering can be used to capture even higher-speed images. Needless to say, it becomes possible.

Another advantage of the CCD frame accumulation mode of the camera is that a still image can be taken using a strobe and a video signal can be equally captured.

Next, based on the formation coefficient obtained by the formation measurement method described above, the membership function is considered (Retsu Yamakawa, "The Idea of FUZZY Computers", November 10, 1988, third print, Kodansha Co., Ltd.) A method of controlling formation by applying is described.

When the control cannot be performed by the image processing arithmetic unit 5, the control is performed by the control computer 100 shown in FIG.

FIG. 7 is a side view showing a wire part of the paper machine.
10 is a head box, 11 is a breast roll, 12 is a bottom wire, 13 is a forming board, 14 is a foil, 15 is a wet suction box, 16 is a top wire, 17,1
8 is a deflector, 19 is a suction box, 20 and 21 are showers for cleaning dirt attached to the bottom wire 12 and the top wire 16, and 22 and 23 are automatic valves for adjusting the amount of water injected from the showers 20 and 21. , 24 indicates a felt, and a J / W ratio between a jet velocity jetted from the head box 10 and the velocity of the bottom wire 12 and the top wire 16;
The foil 14 angle in the initial dewatering region 25, and the deflector 17, 18 indentation amount in the bottom middle dehydration region 26 and the top middle dehydration region 27, respectively, based on the formation coefficient obtained by the formation measurement method. The suction amount of the suction box 19 and the opening degrees of the automatic valves 22 and 23 of the showers 20 and 21 are changed as necessary.

FIG. 8 (i) to FIG.
As shown in (v), the quality of the paper 1 in five steps from “worst”, “bad”, “normal”, “good”, and “worst” to the formation coefficient of the paper 1 (horizontal axis). Applicable degree (vertical axis)
From five membership function curves M _{1 to} M ₅
And a change amount (horizontal axis) of the J / W ratio (here, only the wire speed is increased / decreased) as an example corresponding to each of the membership function curves M _{1 to} M ₅ for specifying the quality of the paper 1. obtained in advance and the true degree (vertical axis) five control membership indicating a function curve M _1a ~M _5a and M _1b ~M _5b to.

The formation coefficient of paper 1 obtained by the formation measurement method and each membership function curve for specifying the quality of paper 1
M ₁ at each intersection between ~M ₅ obtains the degree of in matching, the J / W each control membership indicating a ratio change amount function in correspondence with the degree of the respective matching curves M _1a ~M _5a and M _{1b to} M _5b
When the inference results of the respective J / W ratio change amounts are obtained from, the respective inference results of the J / W ratio change amounts are superimposed and synthesized, and FIG. 8 (vi)
The final membership functions M _La and M _Lb indicating the final inference result of the J / W ratio change amount as shown in FIG.
One of the centers of gravity of _La and M _Lb (final membership function M
The horizontal axis component of the position where the area enclosed by _La or M _Lb and the vertical and horizontal axes is halved) is defined as the increase or decrease in the actual wire speed, and the actual change amount of the J / W ratio is determined to determine J / W. Control the ratio.

The Figure 8, the formation factor indicates the case where 35, the vertical axis component of the point of intersection between the membership function curve M ₁ indicating "worst" of FIG. 8 (i) (matching as an example Degree) is about 0.25, so extend the line horizontally from the intersection to "significantly increase" or "significantly decrease" the wire speed.
The head of the control membership function curve M _1a or M _1b scraping the degree of about 0.25 matching that employs only hatched portion as the inference result of the wire speed decrease amount.
Further, the vertical axis component of the point of intersection between the membership function curve M ₂ showing the "bad" in FIG. 8 (ii) (degree of matching) is about 0.75
Therefore, a line is extended horizontally from the intersection, and the head of the control membership function curve _M2a or _M2b for "increase" or "decrease" the wire speed is cut off at a matching degree of about 0.75, and hatching is performed. Only the part is adopted as the inference result of the wire speed change amount. Furthermore, since the vertical axis component of the intersection of the membership function M ₃ indicating "normal" in FIG. 8 (iii) (degree of matching) is about 0.7, wire speed to extend the horizontal line from the intersection point Is a control membership function curve M _3a that “slightly increases” or “slightly decreases”
Or the head of the M _3b scraped off in the degree of about 0.7 of the matching,
Only the hatched portion is adopted as the inference result of the wire speed change amount. In addition, since the vertical axis component of the point of intersection between the membership function curve M ₄ indicating "good" in Figure 8 (iv) (degree of matching) is about 0.1, wire speed to extend the horizontal line from the intersection point The head of the control membership function curve _M4a or _M4b of "slightly increase" or "slightly decrease" is cut off at a matching degree of about 0.1, and only the hatched portion is adopted as the inference result of the wire speed increase / decrease amount. Moreover, since formation factor for the membership function curve M ₅ indicating the "best" of FIG. 8 (v) is not an intersection case 35, the wire speed "Masa not" or "reduced without the degree of matching for the control membership function curve M _5a or M _5b of "is 0, that is, that the wire speed has to be increased or decreased. Therefore, when the formation coefficient is about 35, when the above inference results are superimposed and synthesized, as shown in FIG. 8 (vi), the degree of matching is increased from "slightly increased" to "increased". , Or between "slightly decrease" and "decrease", the amount of increase or decrease in wire speed is determined. Here, when determining whether to increase or decrease the wire speed, when changing the wire speed for the first time, only one of the centers of gravity (for example, the center of gravity for decreasing) is adopted from the final inference result, and the ground is determined. When the improvement of the formation is recognized (that is, when the difference between the formation coefficient before the current control and the formation coefficient during the current control is positive),
Thereafter, the control is advanced in the direction of decreasing the wire speed, and when the formation is not improved (that is, the difference between the formation coefficient before the current control and the formation coefficient during the current control is negative). Then, the control is advanced in the direction of increasing the wire speed thereafter. Thereby, more efficient control can be performed.

As described above, by using the phage (FUZZY) theory using the membership function together, it is possible to perform not the on-off control but the gentle control that does not suddenly change the paper 1 as the product. Becomes possible.

The J / W ratio was changed in this manner, and as shown in FIG.
If the formation cannot be further improved by repeating the change of the ratio, the membership function is used as in the case of the change of the J / W ratio shown in FIGS. 8 (i) to (vi).
The control is sequentially performed to change the foil angle and the deflector pushing amount to improve the formation.

In controlling the J / W ratio, the result of frequency analysis of the density of the image in the width direction (that is, whether formation is pulling formation or pushing formation) is used to control the J / W ratio. Is
It is also possible to perform control to increase the J / W ratio and to decrease the J / W ratio in the case of pushing formation. By doing so, reliable and efficient formation control can be performed.

Further, at the start of the measurement, in FIG. 1, the camera 3 is raised along the rail 3c to enlarge the field of view of the camera 3, observe the entire formation, and start the control by the above-described formation control method. As the formation improves, camera 3 is moved to rail 3c
The camera 3 is gradually lowered in the field of view, and when the formation is stabilized and the control is almost completed, the camera 3 is moved to the rail 3c.
It is also possible to return to the original large field of view and return to the monitoring state.

This makes it possible to use for delicate control of formation, and can also respond to changes in external conditions (such as changes in raw material conditions) after formation is stabilized.

As another embodiment of changing the field of view, as shown in FIG. 2, automatic apertures 3b-1, 3b-2 are built in, and camera boxes 3a-1, 3b-1
A plurality of cameras 3-1 and 3-2 (in this case, two cameras) stored in 3b-2 are arranged on one side of paper 1 and strobe boxes 2a-1 and 2a-2 are arranged on the other side. The strobes 2-1 and 2-2 stored respectively are arranged.

It is better to arrange the paper 1 in the flow direction. Before the start of the control and after the completion of the control, an image is captured by the camera 3-2 having a large field of view, and the signal is sent to the display device 7 via the cable 8-2 and to the image processing arithmetic unit 5 via the cable 4-2. If the formation is improved after the start of the control and the fine dispersion is required to be determined, the camera is switched to the camera 3-1 having a smaller field of view and the signal is transmitted via the cable 8-1 to the display device. 7 to the image processing arithmetic unit 5 via the cable 4-1 for processing.

This would require multiple cameras,
It is not necessary to move each camera for changing the field of view while keeping each camera fixed, and the field of view can be changed more quickly only by switching a plurality of cameras.

The strobe 2 and the camera 3 used in the formation measurement method described above and the formation control method using the formation measurement method are, as shown in FIG. , Dryer part, calendar part, etc.

Further, the formation measurement method and the formation control method using the formation measurement method of the present invention are not limited to only the above-described embodiment, and various changes may be made without departing from the gist of the present invention. Of course, it can be added.

[Effects of the Invention] As described above, according to the formation measurement method of the present invention and the formation control method using the formation measurement method, the following various excellent effects can be obtained.

(I) Since the conventional method of capturing information as a point is regarded as a surface, it approaches the method of evaluating formation by human eyes and the formation can be quantified and objective, so that objectivity is obtained. or,
The stiffness of the control can be increased by characterizing the dispersion.

(Ii) Quantification of formation and FU using membership function
By using the ZZY theory together, it is possible to perform not only on / off control but also gentle control without abrupt change to the product paper, which can greatly contribute to improving the quality of paper.

(Iii) Since a strobe light is used as a light source, not only off-line but also on-line measurement of high basis weight and high speed can be performed, and a surface can be taken in instantaneously, so that data processing time is short.

(Iv) Long-term monitoring of formation is possible.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an example of an apparatus for implementing a formation measurement method and a formation control method using the formation measurement method of the present invention;
FIG. 2 is a block diagram showing another embodiment in which a plurality of cameras having different visual fields are provided, and FIGS. 3 (a), (b), (c), and (d) are illustrations of image processing in a display device. FIG. 4 is a schematic diagram showing a relationship between a window and a pixel in the display device, FIG. 5 is an explanatory diagram of an image when frequency analysis is performed on pixels constituting an image, FIG. 6 is a diagram showing a frequency analysis result, FIG. 7 is a side view showing a wire part of the paper machine, and FIGS. 8 (i) and (ii).
(Iii) (iv) (v) (vi) is an explanatory diagram of a procedure for determining a J / W ratio change amount based on a formation coefficient, and FIG. 9 is formation control using the formation measurement method of the present invention. FIG. 10 is a flowchart showing an example of the method, FIG. 10 is an overall side view showing an installation location of a strobe and a camera, FIG. 11 is a configuration diagram showing an example of a conventional ground total, and FIG. It is a diagram showing the relationship between the obtained time and formation index. 1 is paper, 2,2-1,2-1 is a strobe, 2a, 2a-1,2a-2 is a strobe box, 3,3-1,3-2 is a camera, 3a, 3a-1,3
a-2 is a camera box, 3b, 3b-1, and 3b-2 are variable aperture devices, 3c is a rail, 5 is an image processing arithmetic unit, 6 is a display device, 9 is an image, 10 is a head box, and 12 is a bottom. Wire, 14 foil, 16 top wire, 17, 18 deflector, 19 suction box, 20, 21 shower, 22,
23 is an automatic valve, 25 is an initial dehydration area, 26 is a bottom middle dehydration area, 27 is a top middle dehydration area, 100 is a control computer, 101 is a control controller, 102 is a formation signal line,
103 is a control signal line, 104 is a communication line, 105 is a control signal line, W
₁ , W ₂ ,…, W _k ,…, W _N is a window, C _av1 , C _av2 ,…, C _avk ,…, C
_avN is the average value of the concentration of each window, V _av1 , V _av2 , ...,
V _avk ,..., V _avN are the primary variance of the concentration of each window, a _v is the average of the primary variance of the concentration as a whole window, V _aav is the variance of the average of the concentration of each window, V _av the second-order dispersion of the concentration as a whole window, M ₁ ~M ₅ is membership function _{curve, M 1a ~M 5a, M 1b} ~M 5b is control membership function curve, M _La, M _Lb final membership Indicates a function.

Continuation of front page (72) Inventor Koji Sakai 3-1-1-15 Toyosu, Koto-ku, Tokyo Ishikawa Shima-Harima Heavy Industries Co., Ltd. Tokyo 2nd Factory (72) Inventor Shigeki Murayama 1 Shinnakaharacho, Isogo-ku, Yokohama-shi, Kanagawa Address Ishikawajima-Harima Heavy Industries, Ltd. Technical Research Institute (56) References JP-A-2-90047 (JP, A) JP-A 1-235837 (JP, A) JP-A-57-197403 (JP, A) JP 3-2649 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) G01N 21/84-21/90

Claims (6)

(57) [Claims] An image of light emitted from a strobe and transmitted through a sheet of paper having a required area is captured by a camera and is displayed as a transmitted light image on a display device of an image processing arithmetic unit, and the transmitted light image is displayed on the display device. Is divided into a required size and a required number of windows, an average value of the density of each window and a primary variance of the density of each window are calculated from the densities of the pixels present in each window, and The average value of the primary variance of the density as the average, the variance of the average value of the density of each window, and the secondary variance of the density of the entire window are calculated, and the average value of the primary variance of the density of the entire window is calculated. A formation measurement method characterized by using any one or a combination of two or more of the variance of the average value of the density of each window and the secondary variance of the density of the entire window as a formation coefficient. 2. A plurality of membership function curves for specifying a plurality of levels of worst to best paper quality from the degree to which the paper formation coefficient is applied based on experimental data obtained in advance. A plurality of membership functions for control indicating the degree to which each of the J / W ratio, the foil angle, and the deflector indentation amount is applied in correspondence with each of the membership function curves for specifying the paper quality. A curve is obtained in advance, and the degree of matching at each intersection between the formation coefficient measured by the formation measurement method according to claim 1 and each membership function curve for specifying the quality of the paper is determined. First, an inference result of each J / W ratio change amount is obtained from each control membership function curve indicating the J / W ratio change amount in accordance with each matching degree, and the J / W ratio change amount is obtained.
A final membership function indicating the final inference result of the J / W ratio change amount synthesized by superimposing the respective inference results of the / W ratio change amount is obtained, and the actual J / W ratio of the J / W ratio is determined based on the final membership function. Determine the amount of change and control the J / W ratio, repeat this until the formation coefficient reduction due to the J / W ratio change is no longer seen,
A formation control method using a formation measurement method, characterized in that a change amount of a foil angle and a deflector depression amount are sequentially determined and controlled in the same manner. 3. The control membership function is determined from the sign of the difference between the formation coefficient of the previous control and the formation coefficient of the current control by repeating the control by the formation control method according to claim 2. A formation control method characterized by selecting. 4. When the measurement is started, the field of view of the camera is enlarged to observe the entire formation, and after the control by the formation control method according to claim 2 is started, the field of view of the camera is improved as the formation is improved. The formation control method is characterized in that the formation is gradually reduced, and when the formation is stabilized and the control is almost completed, the state is returned to the original large field of view and the monitoring state is set. 5. A camera according to claim 2, wherein a plurality of cameras are arranged at different distances from the paper, and when the measurement is started by switching the plurality of cameras, the entire formation is observed with a camera having the largest field of view.
After the control by the described formation control method is started, as the formation is improved, the camera is sequentially switched to a camera having a smaller field of view, and when the formation is stabilized and the control is almost completed, the camera is switched to the camera having the larger field of view and the monitoring state is changed. Formation control method characterized by performing. 6. A shading formation or a pressing formation is determined by frequency-analyzing the density of the transmitted light image in the width direction.
4. The formation control method according to claim 2, wherein the J / W ratio is increased in the case of pulling formation, while the J / W ratio is reduced in the case of pushing formation.