JPH0686271B2 - A method for monitoring the shape of bare rim in a paper manufacturing line - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a shape of a bare ream in a paper manufacturing line for automatically and accurately discriminating the shape and irregularity of the shape of the bare ream and taking appropriate processing. Regarding the monitoring method of.

[Conventional technology]

The production of paper is generally performed by a step of cutting a base paper into a predetermined size by an oval roll cutter, forming a bare ream formed by stacking a predetermined number of sheets, and transporting it to a packaging machine by a conveyor for packaging. If the shape of the bare ream is irregular, for example, if a part of the paper is bulged from the side of the bare ream, the packaging reel will significantly reduce its commercial value. Therefore, it is necessary to monitor the shape of the bare ream conveyed through the cutter until it reaches the packaging machine and eliminate irregularities.

A conventional method for monitoring the shape of a bare ream will be described with reference to a schematic plan view of the conventional monitoring method shown in FIG.

The bare ream 9 formed through a cutter (not shown) is placed on the conveyor 7 and conveyed in the direction of the arrow toward the packaging machine, and is provided on both sides of the path of the bare ream 9 as shown in FIG. The signal processor (not shown) is installed at a position close to each side surface of the bare ream 9 that passes through the detection unit 8 that includes a light source that projects light in a direction perpendicular to the surface of the light source and a photoelectric tube that receives light from the light source. When the bare reams 9 pass through the side of the detection unit 8, if there is a protruding portion 9a from the side surface of the bare ream 9, the protruding portion 9a interferes with the light reception of the photoelectric tube of the detection unit 8. Then, the signal processor issued an alarm signal.

However, such a conventional monitoring method has a low accuracy and has an irregular shape other than the shape of the protruding portion 9a from the side surface of the bare ream 9, for example, the protruding portion only in the traveling direction or the reverse direction of the bare ream 9. There was a defect that certain shapes and bent shapes could not be detected.

[Problems to be solved by the invention]

It is an object of the present invention to provide a monitoring method capable of accurately detecting a protruding portion in any direction or a bend in a bare ream without the above-mentioned drawbacks of the prior art.

In order to achieve this object, various improvement experiments have been repeated with respect to the conventional monitoring method, for example, the position and direction of the detecting portion, but no good result has been obtained. As described above, the improvement of the conventional monitoring method does not achieve the purpose, and therefore, any principle and means which have not been used in the conventional paper manufacturing process are introduced and how to adjust the shape of the bare ream.
There was a very difficult problem regarding whether to apply it to discriminate irregularities.

[Means for solving problems]

The present invention illuminates the entire bare ream being conveyed and, in the case of a shape having a certain irregular portion, gives a proper direction so as to cause the shadow of the portion to be shaded. On the other hand, the present invention has been completed by clarifying that the above problems can be solved by taking images from at least both sides with a TV camera, counting the number of pixels, and comparing with the case of a normal shape.

That is, one aspect of the present invention is to install television cameras on both sides of a bare ream made of a predetermined number of sheets that are cut into a predetermined size and stacked and conveyed by a conveyor through a cutter, on both sides thereof. Illuminating the full shape of the bare reem as seen from the position of the, and if there is at least one of paper squeezing out from the side of the bare ream, retraction, and bending in the bare ream, the shadow of that portion. Under a lighting condition that causes light, the image of the bare reem is momentarily captured by the TV camera against the background having a large contrast with the bare reem, and the normal complete image area on each side of the bare reem and the normal whole area are obtained. It is premised to lead to an image processing device capable of counting the number of pixels for each of the entire image areas including at least three image areas for each side obtained by dividing the shape into at least three areas. May be stored the number of pixels for each image region of the means pursuant the normal shape for naked ream of normal shape,
Next, compare the number of pixels in each image area obtained by imaging under the same conditions for the bare ream to be monitored with the number of pixels in the corresponding image area for the above-described bare ream of normal shape, and if there is a difference, automatically The present invention relates to a method for monitoring the shape of a bare ream in a paper manufacturing line, which is characterized by activating at least an alarm device (hereinafter referred to as the first invention).

Another aspect of the present invention is to install television cameras on both sides and above the moving direction of a bare ream made of a predetermined number of sheets of paper cut and stacked to a predetermined size conveyed by a conveyor through a cutter. When irradiating the whole shape of the bare reem as seen from the position of the television camera and at least one of protrusion of paper from the side of the bare ream, retraction, and bending in the bare reem, Under the lighting that causes a shadow of a part, the naked ream is momentarily imaged by the TV camera against the background having a large contrast with the naked reem, and the normal full-shaped image area and the upper surface of each side of the naked reem are taken. Of the total number of pixels in each of the total areas, which is composed of a larger area than the normal whole shape of at least 3 and at least three areas on each side obtained by partitioning the normal whole shape into at least three Mosquito Leading to an image processing device capable of controlling the normal shape, and storing the number of pixels for each image area of the normal shape in advance under the same conditions for the bare frame to be monitored. The number of pixels for each image area obtained by imaging is compared with the number of pixels for the corresponding image area of the normal shape naked ream, and when there is a difference, at least an alarm device is automatically activated. The present invention relates to a method for monitoring the shape of a bare ream in a paper manufacturing line (hereinafter referred to as the second invention).

Hereinafter, a method of monitoring the shape of a bare ream in a paper manufacturing line according to the present invention will be described in detail with reference to the drawings.

FIG. 1 is a plan explanatory view schematically showing an example of an implementation state of the method of the present invention, and FIGS. 2 to 7 are plan views (a) of (a) of each pattern having an irregular shape of a bare ream. Shows side views that may be shaded under illumination, and Fig. 2 shows a case where a part of the paper sticks out to the TV camera side at right angles to the traveling direction of the bare ream. Fig. 3 shows a case where a part of the paper is pulled in at the right angle to the direction of the bare ream and opposite the TV camera, and Fig. 4 shows a case where a part of the paper protrudes along the direction of the bare ream. , Fig. 5 shows that when a large number of papers stick out along the traveling direction of the bare ream, gradually varying in their extent, and Fig. 6 shows that a part of the paper of the bare ream rotates horizontally and then sideways and barely. Fig. 7 shows a case where a piece of paper of the bare ream is bent, and Fig. 8 shows a case where it protrudes along the direction of movement of the ream. Illustrates each image region of the image side surface of the bare stream in the screen of the image processing apparatus, FIG. 9 is a diagram similarly showing an image area of the image of the upper surface of the bare stream.

[Description of configuration]

In the present invention, first, as shown in FIG. 1, in the traveling direction of the bare ream 9 (shown by an arrow in the figure) conveyed by the conveyor 7 via a cutter (not shown), in the first invention, to both sides thereof. The TV camera 1 is installed. In the second invention, in addition to the case of the first invention, the television camera 1 is installed above the traveling direction of the bare ream 9, that is, above the conveyor 7 (not shown). Then, the naked ream 9 is imaged by the TV camera 1 under illumination, and the illumination is performed so as to satisfy the following conditions. That is, as seen from the position of the television camera 1, at least the entire shape of the bare ream 9 is illuminated and at least the paper protruding portion from the side surface of the bare ream 9, the retracted portion, and the bent portion within the bare ream. If any one is present, it is a light that creates a shadow. In the first aspect of the invention, such illumination is performed only from the side in the traveling direction of the bare ream 9 with the television camera 1, so that as shown in FIG. Illumination by the light source 2 located above may be used. In the second invention, the entire shape of the upper surface of the bare ream 9 is imaged by the television camera 1 from above in the traveling direction of the bare ream 9, but the television camera (not shown) above the side surface of the bare reem 9 Therefore, the illumination for imaging the upper surface may be illumination by a light source at a position higher than the level of the upper surface of the bare ream 9 as long as it does not interfere with the generation of shadows on the side surface due to the irregular shape. The light source 2 that illuminates the side surface of the bare ream 9 may be located above the bare ream 9 and may also serve as the light source that illuminates the upper surface of the bare ream 9.

As shown in FIG. 1, the image of the bare ream 9 is picked up by the television camera 1 with the surface 3 having a strong contrast with the bare ream 9 such as a black surface as a background. In the second invention, since the image is captured from above the bare ream 9, the background conveyor 7 is made to have a high contrast color. The image is taken instantaneously to obtain a still image. In order to image the bare reams 9 conveyed one after another at a predetermined accurate position and to perform the image processing described below without error, a television is used at an accurate timing by using the photoelectric sensor 4 as shown in FIG. It is preferable to operate the camera 1.

The signal thus captured and generated in the television camera 1 is input to the image processing device 5. In this image processing device 5,
You can set an image area of an appropriate shape at any position on the screen, count the number of pixels for the selected color of the image for each image area, and memorize it. If there is a significant difference compared with the number of pixels of, the alarm signal is issued to at least the alarm device 5a. As such an image processing device 5, a commercially available device as an image determination device or the like can be used.

Here, the irregular pattern generated in the bare ream 9 and the associated shadow generation state and line-of-sight state of the surface 3 having a strong contrast will be described. In each figure, the protruding part of the bare ream 9 is 9a, the retracted part is 9b, and the bent part is 9c.
And the shadows of the above-mentioned portions 9a, 9b and 9c are 9a ′, 9b ′ and
Code 9c '. In the first pattern, as shown in FIG. 2A, a part of the paper may protrude from the side surface of the bare ream 9 at a right angle to the traveling direction (arrow direction) of the bare ream 9 on the television camera 1 side. . In this case, the protruding portion 9a is illuminated by obliquely upward or downward on the side surface as shown in FIG.
A shadow 9a 'is created as shown in. The second pattern is the case where the first pattern is viewed from the opposite side, so that the television camera 1 (see FIGS. 3 to 7) is perpendicular to the traveling direction of the bare ream 9 as shown in FIG. Although the illustration of the position of the television camera 1 in FIG. 2 is omitted, it is the case where a part of the paper is pulled in on the side opposite to (the same as FIG. Also in this case, a shadow 9b 'is formed on the lead-in portion 9b as shown in FIG. The third pattern is a case where a part of the paper protrudes along the traveling direction of the bare ream 9 as shown in FIG. Of the two surfaces, which are perpendicular to the traveling direction of the bare ream 9, that is, the front surface and the opposite surface are the front surface and the rear surface, respectively. In that case, it protrudes to the front, but it may also protrude to the rear. In this case, in the lead-in portion 9b, the surface 3 having high contrast can be seen from the first speed of the television camera, or a shadow 9b 'is formed even if it cannot be seen. The fourth pattern is a special case of the third pattern, and as shown in FIG. 5 (a), a large number of papers are gradually protruding along the advancing direction of the bare ream 9 while gradually changing their degrees. When viewed from the side of the TV camera 1, the bare ream 9 has a gentle curved surface on each of which a protruding portion 9a and a retracting portion 9b are formed, as shown in FIG. 5B. In the space after the paper is drawn in, for example, a black surface 3 having a strong contrast (which will be described below by a black example) is seen. In the fifth pattern, as shown in FIG. 6 (a), a part of the paper of the bare ream 9 is displaced in two horizontal directions and is accompanied by rotation, so that at least one of both side surfaces and the front surface and the rear surface. Part that extends beyond at least one of the
In the case where the 9a and the retracted portion 9b are formed, and when viewed from the television camera 1 side, a shadow 9a 'due to the protruding portion 9a and a shadow 9b' due to the retracted portion 9b are formed on the side surface as shown in FIG. 6 (b). Has occurred. The sixth pattern is naked ream 9
When the bent portion 9c is present in a part of the paper of FIG. 7 and is present inside the bare ream 9 as shown in FIG. As shown in (b), a shadow 9c 'appears on at least the side surface.

In order to determine the irregular-shaped bare ream 9 having various patterns as described above, first, the normal-shaped bare ream 9 is placed on the conveyor 7.
An image is placed on the image processing apparatus 5 at a predetermined position, and an image is stored in the image processing apparatus 5, and each image area is set based on this image as follows. First, for each side of the bare ream 9, as shown in FIG. 8, an image area I (indicated by Roman numerals in the drawing; the same applies hereinafter) of the entire side and the entire shape of this side are divided into at least three sections. At least three areas II, III, IV, V, etc. obtained by the above are set. The number of sections defining the entire side surface is such that the short side of the paper forming the bare ream 9 is the side surface.
For example, it is appropriate to divide the naked ream 9 into three in the case of A4 size, four in the case of B4 size, and almost equally in both cases. Indicated. Such divisions and image areas are set for each side. In the second invention, the image is set also for the image of the entire upper surface of the bare ream 9, but in this case, as shown in FIG. 9, the image area VI larger than that of the entire shape 6 of the upper surface is set.

After setting each area like this or each time you make each setting,
The number of pixels for the set color of the image of the bare frame 9 having a normal shape is counted and stored for each image area.
The color of the image is usually white in the case of paper, the shaded portion is black or gray, and the surface 3 is also used in a color having a high contrast such as black. Therefore, for example, when the number of white pixels is counted and stored, the number of pixels (A) over the entire area of each image area is obtained.

Then, when the bare ream 9 to be monitored is placed on the conveyor 7 and conveyed and reaches a predetermined position, the television camera 1 instantaneously takes an image by the signal from the photoelectric sensor 4 and the image area I to For V, the number of pixels (a) in the black or gray portion is counted for each image area, and for the image area VI, the number of white pixels (b) is counted. If the number of pixels (a) is counted in any of the image areas I to V, the second
The bare ream 9 has any of these irregular shapes, as can be seen by fitting each of (b) in FIGS. Therefore, the a / A is calculated by the image processing device 5 for each image area of the above I to V, and when the value is equal to or more than the fixed value set for each image area, the alarm device 5a is automatically operated. To operate. By this alarm, the bare ream 9 having the irregular shape may be manually or automatically removed from the transport path, and appropriate processing may be performed as necessary to restore the original.

Since the irregular shapes shown in FIGS. 2 and 3 have the same shape due to the relationship between the front and back sides, the shadow state is different between the two, so the TV cameras 1 are installed on both sides with respect to the traveling direction of the bare ream 9. By performing the image pickup in this manner, there is no possibility of omission of detection caused by the light shadow on that side when the image is picked up from only one side. In addition, as in the case of FIG. 4 and FIG.
Even if the b ′ and 9c ′ parts are small, the a / A value is increased to increase the detection accuracy by providing an image area in which the entire side surface is divided into at least three or more parts. Of.

In the second invention, the area VI is further added. When the number of pixels (b) is counted in the image area VI, as shown in FIG. 9, each of (a) in FIG. 2 to FIG. Irregular shapes other than those shown in Fig. 7) are detected, and a /
As in the case of A, when the value of b / A is a certain value or more, the detection performance can be further improved by operating the alarm device 5a. Such constant values of a / A and b / A are empirically determined depending on the degree of commercial value required, and examples thereof will be shown in the examples.

With the image processing device 5, it is also possible to make a judgment by reversing the black and white of the above image from the actual one.

Note that the color of the paper is generally white, but the shadow is not necessarily dark black, so the number of pixels of the shadow may not be counted in the raw image. Therefore, an appropriate gray color between white and black is set as a reference level, all the colors on the black side of this reference level are set to black, and the colors on the white side are set to white (this is binarized. The image processing device 5 that does so is commercially available, and it is preferable to use such a device in the present invention.

〔Example〕

 Hereinafter, the present invention will be described in more detail with reference to examples.

B4 size or A4 size pure white PPC paper (thickness 0.09mm per sheet) 100
Each of the two kinds of bare reams 9 having 0 sheets stacked thereon is formed into various irregular shapes, placed on the conveyor 7, and conveyed.
The shape was monitored as shown. That is, the TV cameras 1 with mechanical shutters are attached to the movable camera stand and installed on both sides of the conveyor 7, and 100 V / 100 W incandescent lamps as light sources 2 for illumination are attached to each TV camera 1 approximately two above. Photoelectric sensor 4 for timing
Is installed at a predetermined position, and a background plate having a matte black surface 3 is installed on the opposite side of each TV camera 1, and the image processing device 5
Fuji Electric's multi-window MW-2600 (screen division of effective screen H255 x V220, number of image areas that can be set per screen 32
Pieces) were used. In image processing, black and white were reversed and binarization processing was performed. A lens hood was attached to the lens of the TV camera 1 to avoid incident of reflected light from surrounding objects.

The transport conditions were as follows.

Line speed (conveyor speed) B4 size 7.4 m / min A4 size 9.2 m / min A4 size 10.5 m / min Number of bare reams passed (processed) B4 size 20.7 ream / min A4 size 29.5 ream / min A4 size 33.6 ream / min The ream spacing was 100 mm in all cases.

The area of the side surface of the naked ream 9 was set to 3 in A4 and 4 in B4.

The detection situation is investigated for each irregular shape pattern of the bare ream 1, and there is almost no omission of the irregular shape that requires processing and a false alarm (normal shape or irregular shape that does not require processing is detected. Corresponding to the size of the irregular shape irregular portion in the detection situation without the
The a / A value was obtained as follows.

(I) In the case of the first pattern (FIG. 2) and the second pattern (FIG. 3): The protruding portion (thus the retracted portion) is 3 mm or more and the number of sheets of paper overlapped is 4 or more.

a / A = 0.05 (ii) In the case of the third pattern (Fig. 4): The protruding portion is 5 mm or more and the number of overlapping sheets is 4 or more.

a / A = 0.03 (iii) For the fourth pattern (Fig. 5): The maximum protruding portion is 5 mm or more.

a / A = 0.1 (iv) In the case of the fifth pattern (Fig. 6): The protruding portion on the front surface or the rear surface is 5 mm or more, and the number of sheets of paper overlapped is 4 or more.

a / A = 0.03 (v) In the case of the sixth pattern (Fig. 7): The number of sheets that are folded and folded while overlapping is two or more.

a / A = 0.05 When the bare reams 9 of A4 size and B4 size were monitored in a normal production line according to the judgment criteria determined as described above, it was found that a bare ream 9 of irregular shape was accurately and rarely needed. It could be detected automatically.

〔effect〕

According to the method of the present invention, a bare ream being conveyed is installed with TV cameras on both sides to illuminate the whole shape of the bare reem and to photograph it under appropriate illumination that causes a unique shadow from the irregular shape. The number of pixels of the image is counted using an image processing device and compared with that of a normal shape, so that a bare ream having an irregular shape can be detected extremely accurately and automatically, and It is possible to improve the product quality and improve the efficiency by subjecting the removed bare ream having an irregular shape to an original treatment by appropriately treating it.

[Brief description of drawings]

FIG. 1 is a plan explanatory view schematically showing an example of an implementation state of the method of the present invention, and FIGS. 2 to 7 are plan views of (a) of each pattern having an irregular shape of a bare ream. Fig. 2 shows side views that may be shaded under illumination, and Fig. 2 shows the case where a part of the paper sticks out to the TV camera side at right angles to the traveling direction of the bare ream. Fig. 3 shows that when a part of the paper is pulled in at the side opposite to the illumination side at a right angle to the moving direction of the bare ream, and Fig. 4 shows that when a part of the paper protrudes along the moving direction of the bare ream, Fig. 5 shows that when a large number of papers stick out along the traveling direction of the bare ream, gradually varying in degree, and Fig. 6 shows that a part of the paper of the bare ream rotates horizontally and Figure 7 shows a case in which a piece of bare ream paper is bent, and Figure 8 shows image processing when it protrudes along the traveling direction. Illustrates each image region of the image side surface of the bare stream at location screen, FIG. 9 is a view similarly showing an image area of the image of the upper surface of the bare stream, the
FIG. 10 is a schematic plan view of a conventional monitoring method. 1 …… TV camera 2 …… Light source 3 …… High contrast surface 4 …… Photoelectric sensor 5 …… Image processing device 5a …… Alarm device 6 …… Overall shape of bare ream 7 …… Conveyor 8 …… Detection Part 9 ...... Bare ream 9a …… Overhanging part 9a ′ …… Shadow 9b …… Retracting part 9b ′ …… Shadow 9c …… Bent part 9c …… Shadow I, II, III, IV, V, VI …… Each area

Claims (2)

[Claims] 1. A television camera is installed on each side of a bare ream made of a predetermined number of sheets of paper cut to a predetermined size and stacked and conveyed by a conveyor through a cutter, and the television cameras are located at the both sides. Illuminates the whole shape of the naked reem as seen from the above, and at least one of the protrusion of the paper from the side of the naked ream, the retraction, and the fold in the naked ream produces a shadow of the part. The naked ream is momentarily imaged by the TV camera against the background of a large contrast with the naked reem under illumination to show the normal full-shape surface area of each side of the naked reem and the normal whole shape. In order to guide the image processing apparatus capable of counting the number of pixels for each of the entire image areas including at least three image areas for each side surface obtained by partitioning into at least three, a normal form The number of pixels for each image area of the normal shape is stored for each naked ream, and then the number of pixels for each image area obtained by imaging under the same conditions for the naked ream to be monitored A method for monitoring the shape of a bare ream in a paper manufacturing line, which automatically activates at least an alarm device when there is a difference in the number of pixels in a corresponding image area for a bare ream having a different shape. 2. A television camera is installed on both sides and above the traveling direction of a bare ream composed of a predetermined number of sheets cut and stacked to a predetermined size and conveyed by a conveyor through a cutter. It illuminates the whole shape of the bare reem when viewed from its position, and if there is at least one of protrusion of paper from the side of the bare ream, retraction, and bending in the bare ream, the shadow of that portion is shaded. Under the lighting that is produced, the naked ream is momentarily imaged with the TV camera against the background with a large contrast with the naked reem. It is possible to count the number of pixels for each area of the entire area consisting of an area larger than the shape and at least three areas for each side obtained by partitioning the normal whole shape into at least three Introducing to the image processing device is performed in advance for a normal shape bare ream, the number of pixels for each image area of the normal shape is stored, and then imaging is performed for the monitored bare ream under the same conditions. A paper manufacturing method characterized in that the number of pixels in each obtained image area is compared with the number of pixels in the corresponding image area of the above-described normal-shaped bare ream, and at the same time, at least an alarm device is automatically activated. How to monitor the shape of bare reams on the line.