JPH07243808A - Method and apparatus for inspection of label as well as lebel image processor - Google Patents

Abstract

PURPOSE:To inspect a plurality of labels by a method wherein both side faces of a container on which a plurality of labels have been pasted are imaged by TV cameras and the pasted state of the labels is found on the basis of images by both TV cameras. CONSTITUTION:TV cameras 6, 7 are installed in directions on both mutually opposite faces of a bottle 1, passage detection sensors 8, 9 are installed in directions on both side faces of a cap 2 for the bottle 1, and the sensors 8, 9 are used for a passage timing at imaging fields of view of the cameras 6, 7 and for an image processing timing at an image processing part 10. The processing part 10 takes into images which have been imaged by the cameras 6, 7, it compares respective criterion values and allowable values on the basis of the images regarding whether the interval between labels 3, 4 is a target interval or not, whether the height of the labels 3, 4 is a target height or not and whether the labels 3, 4 are tilted or not, and it inspects whether the labels have been pasted well or not. Thereby, the pasted position of the labels 3, 4 in a plurality can be inspected without designating the direction of a container.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a label inspection device used for inspecting a label attached to a container.

[0002]

2. Description of the Related Art In the conventional label inspection apparatus, in the case of inspecting the position and interval of labels attached to a cylindrical container such as a bottle, for example, a rotational deviation occurs with a reference label end or a positioning mark as a target. The inspection is achieved by correcting the orientation of the inspection target label by the correction mechanism or by capturing the image with the label position during the pasting being limited and managing the position on the screen.

[0003]

In the above-mentioned conventional example, it is difficult to perform label inspection in the case where the number of labels to be attached is plural or in an environment where position correction cannot be performed. Further, the rotation deviation correction mechanism is required to have high accuracy, and the mechanism is complicated.

An object of the present invention is to provide a label inspection apparatus which enables label inspection, particularly plural label inspections, without using a rotation deviation correction mechanism.

[0005]

According to the present invention, a container with a plurality of labels attached thereto is imaged with a TV camera from both side surfaces of the container facing each other with the container sandwiched between the two TVs. A label inspection method is disclosed in which the attachment state of the plurality of labels is obtained from the image of the camera and the label inspection is performed.

Further, according to the present invention, with respect to a container to which a plurality of labels are attached, the T can be applied from both side surfaces facing each other with the container sandwiched therebetween.
The V-camera images the labeled container, the sticking positions and the sticking intervals of the plurality of labels are obtained from the images of the two TV cameras by using the relational expression between the imaging coordinates and the actual size of the container, and the sticking of the label is performed. Disclosed is a label inspection method for performing a label inspection of good and bad positions and application intervals.

The present invention further includes a carrier line for carrying a container having a plurality of labels attached thereto, and first and second TV cameras installed on opposite side surfaces of the container on the carrier line.
Disclosed is a label inspection apparatus including an image processing unit that processes an image including a label captured by a first TV camera and a second TV camera, detects a label attachment state, and determines whether the label attachment is good or bad.

Further, the present invention comprises a carrier line for carrying a container having a plurality of labels attached thereto, and first and second TV cameras installed on opposite side surfaces of the container of the carrier line.
The images including the labels captured by the first and second TV cameras are processed to obtain the label sticking positions and the sticking intervals from the memory that stores the relational expression between the image pickup coordinates and the actual dimensions of the container, and the label sticking positions and the sticking Disclosed is a label inspection apparatus including an image processing unit that determines whether a space is good or bad.

The present invention further includes an image pickup means for picking up an image of a labeled container, and means for processing an image from the image pickup means to obtain a label attachment state by utilizing the relationship between the image pickup coordinates and the actual size of the container. , A label image processing device comprising the following.

[0010]

According to the present invention, the label attachment state is obtained by taking images of the labeled container from opposite positions on both sides using two TV cameras. Further, as the pasting state, the pasting position and the pasting interval of the label are obtained from the relationship between the imaging coordinates and the actual size of the container, and the good or bad of the position and the interval is determined by this.

[0011]

EXAMPLE FIG. 2A shows an example of a bottle container to be inspected. The bottle container 1 has a lid 2, and two labels 3 and 4 are attached to the side surface. The two labels 3 and 4 are respectively printed with the product name, usage, effect description, etc., and are attached to different positions on the circumference of the bottle. Labels 3 and 4 often do not have the same size.

FIG. 2B shows an example of transporting the bins 1 that are sequentially transported on the transport line 11. The transfer line is, for example, a belt conveyor, and bins 1 are successively placed on the transfer line to carry in the direction of the arrow. Although not shown in the figure, there is an automatic sticking process for automatically sticking the labels 2 and 3 to the bottle on the upstream transport line.
In (b), two TV cameras 6 and 7 and passage detection sensors 8 and 9 are provided to inspect the attached label.

The passage detection sensor 8 is installed in the vicinity of the TV camera 6 and gives a timing such that the bottle can be imaged from the front in the imaging field of view of the TV camera 6. The passage detection sensor 9 also has a similar function to the TV camera 7.

The TV cameras 6 and 7 are provided with 18 on both sides of the bin.
It is installed at a position facing 0 ° so that both sides of the bottle can be imaged from the front. Then, under the action of the sensors 8 and 9, both sides of the bin passing through the imaging visual field are sequentially imaged from the front thereof.

FIG. 1 is a diagram showing an embodiment of the label inspection apparatus of the present invention. In FIG. 1, two TV cameras 6 and 7 are installed on both sides of the bottle 1 facing each other, and two passage detection sensors 8 are installed on both sides of the lid 2 of the bin.
9 are installed. The sensors 8 and 9 detect the passage of the bottle with the passage of the lid.
7 may be installed in parallel to detect the passage of both side surfaces of the bottle. The bin 1 moves in the direction perpendicular to the paper surface as shown in FIG. 1B.

The passage detection sensors 8 and 9 are connected to the TV camera 6 and
Bin passing timing in the imaging field of view 7 and the image processing unit 1
Used for image processing timing at 0. Therefore, the outputs of the sensors 8 and 9 are input to the image processing unit 10 and also to the TV cameras 6 and 7 via the image processing apparatus 10. The image processing unit 10 is composed of a computer such as a microcomputer and a dedicated LSI.
The video imaged in 7 is taken in and the predetermined image processing is performed.

FIG. 3 shows various sizes of the bin 1. The two labels 3 and 4 each have a constant width in the circumferential direction and are to be attached at intervals of a target dimension. The TV cameras 6 and 7 are arranged on a straight line passing through the center of the bottle and facing each other by 180 °. In the positional relationship shown in the figure, both the TV cameras 6 and 7 can image the deviation of the label 3 and the deviation of the label 4. By obtaining these shift amounts from the image, the sticking intervals of the labels 3 and 4 are calculated. Further, the heights of the labels 3 and 4 and the inclination angles of the attachment of the labels 3 and 4 are also calculated from the images of the TV cameras 6 and 7.

FIG. 4 is an explanatory diagram of image processing. Figure 4
It is assumed that the TV cameras 6, 7 are in the positional relationship with the bin 1 and the labels 3, 4 as shown in (a). The image captured by the TV camera 6 in this positional relationship is shown in FIG.
An image captured by the camera 7 is shown in FIG. When S is the start side and E is the end side, in the TV cameras 6 and 7 as shown in FIG. 4A, S and E are as shown in FIGS. 4B and 4C.

FIGS. 4B and 4C are picked-up images, and the roundness of the bin is linear. Therefore,
The imaging coordinates do not match the actual size of the actual bin.
Therefore, the relationship between the imaging coordinates and the actual size of the bin is stored in the memory in advance. This is shown in FIGS.

Various inspection objects according to FIG. 4 will be described below. (1) Inspection of whether the label interval is the target interval. The center position of the bin 1 is calculated from the captured image. Figure 4
As shown in (b), the distance a ₁ from the left end of the screen to the left end of the bin is calculated. Calculate the distance b ₁ from the left screen edge to the right edge of the bin. These two distances a ₁ , b
Distance L ₁ from the left end of the screen of the center position 0 ₁ to _1,

## EQU1 ## L ₁ = (b ₁ −a ₁ ) / 2 + a ₁ = (a ₁ −b ₁ ) / 2. Similarly, from the image of FIG. 4C, the center position 0 ₂
The distance L ₂ to

## EQU2 ## L ₂ = (b ₂ −a ₂ ) / 2 + a ₂ = (a ₂ + b ₂ ) / 2.

Next, to calculate the distance c _1, d ₂ of the label 3 and the center position 0 _1, 0 _2. This is to find the distance between the right end of the image of label 3 and 0 ₁ in FIG.
In FIG. 4C, the distance between the left end of the image of label 3 and 0 ₂ is calculated. Similarly, to calculate the distance d _1, c ₂ of the label 4 and the center position 0 _1, 0 _2.

There are two types of label intervals. In FIG. 4A, the two labels 3 and 4 have two spacing portions A and B on both sides. There is a method of sticking the two intervals A = B, and a method of sticking | AB− = K ₀ (constant).

Therefore, according to FIGS. 5A and 5B, c
Actual dimensions c ₁₀ , d ₁₀ , c ₂₀ , d ₂₀ for ₁ , c ₂ , d ₂ are obtained. If A = B

[Equation 3] | (c ₁₀ + d ₁₀ ) − (c ₂₀ + d ₂₀ ) | ≦ ε ₀ is checked. ε ₀ is an allowable value. On the other hand, if | AB | = K ₀ ,

## EQU4 ## It is checked whether | (c ₁₀ + d ₁₀ ) − (c ₂₀ + d ₂₀ ) | ≦ K ₀ + ε ₁ is satisfied. ε ₁ is an allowable value. If the expressions (3) and (4) are not satisfied, it is determined that the attachment is defective and the bin is excluded from the transport line.

(2) Inspection of whether or not the label height is the target height. From the image of FIG. 4B, the height e ₁ from the bottom of the screen,
f ₁ is obtained, and heights e ₂ and f ₂ from the bottom surface of the screen are obtained from the image of FIG. And the height e ₁ of the label 3
And f ₂ are compared according to the following equation.

## EQU5 ## Similarly, e ₁ ≤K ₁ + ε ₂ , or f ₂ ≤K ₁ + ε ₂ ,

## EQU6 ## Comparison of e ₂ ≤K ₂ + ε ₃ or f ₁ ≤K ₂ + ε ₃ is performed. If Expressions 5 and 6 are satisfied, it is determined that the height is attached to the standard value, and if not, it is determined that the height is defective. ε ₂ and ε ₃ are allowable values.

Further, when it is determined that the heights of the labels 3 and 4 are attached to a certain standard value (height difference) having a constant height,

[Formula 7] | f ₁ −c ₁ | ≦ K ₃ + ε ₄ or (and) | f ₂ −c ₂ | ≦ K ₃ + ε ₄ is checked. If this condition is satisfied, it is determined that the heights of the labels 3 and 4 are attached with a relative difference of the standard value K ₃ . Otherwise, it is determined to be defective. ε ₄ is an allowable value. Furthermore, the heights of the bottom surfaces of the labels 3 and 4 can be similarly checked by obtaining the bottom surface height.

(3) Inspection of whether the label is tilted. The label 3 is tilted according to the following equation.

[Equation 8] | e ₁ −f ₂ | ≦ ε ₅ The inclination of the label 4 is

[Equation 9] | e ₂ −f ₁ | ≦ ε ₆ . ε ₅ and ε ₆ are allowable values. If the equations 8 and 9 are satisfied, it is determined that there is no inclination, and if they are not satisfied, the label that is not satisfied is determined to be defective sticking.

(4) Various data e ₁ , f ₁ , e ₂ , f ₂ , c ₁ , d ₁ , in calculating the above (1) to (3)
c ₂ and d ₂ are automatically obtained by image processing. It is also possible to use a man-machine for the mouse cursor. Various calculation formulas are realized by software.

(5) In addition, when the height or inclination of the label is inspected, the sizes e ₁ , f ₁ , e ₂ , f ₂ from the reference positions P ₁ and Q ₁ are calculated. However, this is based on the assumption that the bottom surface positions P ₁ and Q ₁ are substantially equal in the screens of FIGS. 4B and 4C. The position of the bins is controlled as the center position in the width direction on the transfer line, and P ₁ and Q ₁ are set so that P ₁ = Q ₁ by adjusting the TV cameras 6 and 7 in advance. I am doing it.
Such a thing is possible even in a non-restraining type transfer line as shown in FIG. A line for transporting bottles in a constrained form as shown in FIG. 6 can be realized without performing position control. Incidentally, 12 is a bottle restraining portion. Of course, | P ₁ -Q ₁ |
= K ₄ (constant value), the value K ₄
Should be corrected for one screen. With respect to the values of P ₁ and Q _1, the center coordinates of c ₁ , d ₁ , c ₂ and d ₂ are determined, and the center coordinates are determined. The reason for this is that the position of the bin on the transport line is constant, but the orientation of the bin is various and the positional relationship of the labels changes variously from the imaging field of view. This is because it is necessary to obtain the coordinates of 0 ₁ and 0 ₂ to obtain them. On the other hand, if P ₁ ,
When Q ₁ is originally variable and indefinite, e ₁ ,
Since f ₁ , e ₂ , and f ₂ are obtained based on P ₁ and Q ₁ , they are not reliable as data. In this case, by obtaining the positions from the reference position to the labels 3 and 4 with the specific portion of the neck portion of the bottle as a reference, the height and the inclination can be accurately detected and the inspection can be performed.

(6) Further, when the height and the inclination are detected, if the bin has a curved shape instead of a straight line in the height direction, the imaging coordinates as shown in FIGS. It is necessary to obtain the relationship with the actual size in advance and store it in memory.

According to the present embodiment, two TV cameras capture images of the label from opposite positions on both sides of the bin,
Two images were obtained, and the interval, height, and inclination of the two labels could be detected from this image. Then, by comparing with the reference value and the allowable value, it is possible to inspect whether the label is affixed or not. If it is defective, remove it from the transport line.

Although two TV cameras are used, by picking up an image from another TV camera from above, it is possible to check the arrangement position of the bins in the width direction on the transfer line, and to check the height and inclination. Can be offered. Although it is a bottle, it can also be used for label inspection of other containers (articles) such as cans. In addition, it is possible to inspect one label or three or more labels.

[0032]

According to the present invention, a plurality of TV cameras are arranged around a container to be supplied, and label images affixed to the container are simultaneously captured by all the cameras, and image processing is performed. It is now possible to inspect the label attachment position, spacing, height, inclination, etc. without specifying it.

[Brief description of drawings]

FIG. 1 is a diagram showing an embodiment of a label inspection device of the present invention.

FIG. 2 is a diagram showing a bottle to which a label is attached, which is one of the inspection targets of the present invention, a transport state of the bin on a transport line, and an arrangement of a TV camera.

3 is a diagram showing various sizes of the bins in FIG. 2 and a layout relationship of TV cameras.

FIG. 4 is a diagram showing an image captured by the TV camera of the present invention and an example of measuring various data thereof.

FIG. 5 is a diagram showing the relationship between the imaging coordinates and the actual size according to the present invention.

FIG. 6 is a diagram showing another example of a transport line.

[Explanation of Codes] 1 Bin 2 Lid 3, 4 Label 6, 7 TV camera 8, 9 Passage detection sensor 10 Image processing unit 11 Conveying line 12 Container restraining unit

Claims (7)

[Claims] 1. A container with a plurality of labels attached thereto is imaged by a TV camera from both side surfaces of the container facing each other with the container sandwiched therebetween, and the images of the two TV cameras are used to detect the plurality of the labeled containers. A label inspection method in which the label attachment state is obtained and the label inspection is performed. 2. The label inspection method according to claim 1, wherein the pasting state is at least one of a pasting position, a pasting interval, and a height / inclination of a label. 3. A container with a plurality of labels attached thereto is imaged with a TV camera from both side surfaces of the container facing each other with the container sandwiched therebetween, and the images of the plurality of labels are taken from the images of the two TV cameras. A label inspection method in which the label application position and the application interval are obtained by using the relational expression between the imaging coordinates and the actual size of the container, and the label application position and the application interval are inspected for good and bad labels. 4. The container according to claim 1, wherein the container is carried on a carrier line, and the two TV cameras are set on both sides of the carrier line to image the container. Label inspection method according to any one of. 5. A carrier line for carrying a container having a plurality of labels attached thereto, first and second TV cameras installed on opposite side surfaces of the container on the carrier line, and first and second TV cameras. A label inspection apparatus comprising: an image processing unit that processes an image including a label captured by a TV camera to detect a label attachment state and determines whether the label attachment is good or bad. 6. A carrier line for carrying a container having a plurality of labels attached thereto, first and second TV cameras installed on opposite side surfaces of the container on the carrier line, and first and second TV cameras. The image including the label imaged by the TV camera is processed to obtain the label attachment position and the attachment interval from the memory that stores the relational expression between the imaging coordinates and the actual size of the container, and the label attachment position and the attachment interval are good or bad. A label inspection apparatus comprising an image processing unit for determining the 7. An image pickup means for picking up an image of a labeled container, and means for processing an image from the image pickup means to obtain a sticking state of a label by utilizing a relationship between image pickup coordinates and an actual size of the container. Label image processing device.