JPH0546898B2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field]

This invention inspects colored capsules by capturing images with a black and white TV camera and processing the image signals to determine whether the color combination of the cap and body of the target capsule in the fitted state conforms to the standard. Regarding the method.

[Conventional technology]

Pharmaceutical capsules often have colored caps and bodies, mainly to facilitate identification of the drug. There are approximately 40 capsule colors that are universally available.
The cap and body may be the same color or two different tones. The company name and product code number are also printed on the colored cap and body. Now, in order to automatically inspect whether the color combination of the cap and body of the target capsule in the mated state conforms to the standard, it is best to take an image with a color TV camera and process the image based on the video signal. This is an accurate method. However, this method has the disadvantage that the process is complicated and is disadvantageous in terms of cost. Therefore, attempts have been made to inspect color combinations by capturing images with black and white TV cameras and performing image processing based on the video signals. In this case, for color identification, the lightness of the three color attributes of hue, lightness, and saturation is used as a substitute. In addition, as a practical issue, it is necessary to consider not only the inspection of the color combination of the cap and the body, but also the inspection of "hangnail" defects that may occur at the fitting portion of the cap and the body. Here, "hangnail" is described in detail later, but when the cap and body fit together,
If the opening ends touch each other with some deviation, the weaker one will break into strips and enter either the outside or the inside of the other party. This defective state is more likely to occur during fitting after filling than before filling, since the opening end of the body is distorted and hardened by filling with the drug. Now, as will be described in detail later, uniform diffuse illumination in all directions is suitable for inspecting color combinations, while directional enhanced illumination is suitable for inspecting hangnails. Moreover, "hangnail" defects are much more common than color combination defects, so emphasis is inevitably placed on highlighting lighting.
The lighting conditions for color combination inspection may be poor and the inspection may be inaccurate. The above-mentioned "hangnail" and the illumination method involved in the inspection will be explained with reference to the drawings.
FIG. 9 relates to the capsule; a is a side view of the cap, b is a side view of the body, c is a side view of the pre-fitted state, and d is a side view of the final fitted state. In the figure a, the cylindrical portion of the cap 20C is provided with a groove C1 around the circumference and one recess C2, and in the figure b, a groove B1 around the circumference is provided near the opening of the body 20B. , and one air vent recess B3 are provided. Figure c shows the state before the drug is filled, and the recess C2 of the cap 20C fits into the groove B1 of the body 20B, preventing them from coming off each other. Figure d shows the state after drug filling, and the cap 20C is connected to the body 20B.
When fitting into the cap 20C, the air inside the cap 20C is easily fitted without being compressed by the air vent recess B3, and finally the groove C1 of the cap 20C
They fit into the groove B1 of the body 20B and are prevented from separating from each other. FIG. 10 relates to a capsule in a "hangnail" state with a cut on the body side, and a is a cross-sectional view thereof, and b is a plan view thereof. In these figures, when the cap 20C and the body 20B are fitted, if the openings of the cap 20C and the body 20B touch each other with some deviation, the weaker side of the body 20B will be cut by the other party. As it is pushed in, the cut band-shaped portion 20b becomes a "hangnail" and protrudes to cover the outside of the cap 20C. Figure 11 shows a "hangnail" where the cap side is torn.
Regarding the capsule in this state, a is a cross-sectional view thereof, and b is a plan view thereof. Conversely, the cap 20C side is weak and breaks, forming a "hangnail" 20c and sinking into the inside of the body 20B. Next, we will discuss the lighting method. Fig. 12 relates to the case of conventional diffuse illumination; a is a side view of the capsule;
b is a schematic diagram of a video signal when the colors are different, and c is a schematic diagram of a video signal when the colors are the same. Figure b shows the cap 20.
C is white, body 20B is red, and when the image is captured under uniform diffused illumination from all directions, white and
In the video signal for one horizontal scanning period in the axial direction by a black TV camera, the white color of the cap 20C is brighter than the red color of the body 20B, and the brightness of the white color of the cap 20C is greater than that of the red color of the body 20B. There will be a step. Also, c in the same figure shows cap 2.
When both 0C and the body 20B are white, no step occurs in the green part of the cap 20C with a video signal for one horizontal scanning period in the axial direction by a black and white TV camera under the same illumination. Note that the small protrusion at the edge indicates a small increment due to reflection at the open end surface 20D of the cap 20C. In this way, it is possible to distinguish between different colors and the same color depending on the presence or absence of a step in the video signal at the boundary. FIG. 13 relates to a conventional example of emphasized illumination, in which a is a side view of a capsule, b is a schematic diagram of a video signal when the colors are different, and c is a schematic diagram of a video signal when the colors are the same. 1st
Figure 3c shows the cap 20C being white, the body 20B being red, and one horizontal scanning period in the axial direction by a black and white TV camera when the image was captured under emphasized illumination from the direction of arrow P in figure a. In the video signal, the white color of the cap 20C has a higher brightness than the red color of the body 20B, but due to the strong reflection of light in some areas due to the emphasis illumination, protrusions are produced here and there, and the border area, that is, the edge of the cap 20C. indicates the peak value. Furthermore, if the direction of the emphasizing illumination is reversed from left to right, a shadow at the boundary portion, ie, the edge of the cap 20C, is created on the body 20B side, and a sharp recess (not shown) is created in the video signal. FIG. 3C shows a video signal when both the cap 20C and the body 20B are white. In short, under enhanced lighting, the reflection at the opening end of the cap 20C is strong, or the shadows around the edges become dark, the video signal peaks upward or downward, and it is not clear whether there is a step or not. Therefore, it becomes impossible to accurately distinguish between capsules of the same color and capsules of different colors. On the other hand, for the purpose of inspecting the presence or absence of "hangnails" in the capsule, emphasized illumination from one direction is suitable for the following reasons. Returning to Figures 10 and 11,
P, Q, R, S in a capsule with a "hangnail"
Emphasis illumination in each arrow direction, that is, almost parallel to the plane formed by the capsule axis and the TV camera optical axis.
Under lighting that illuminates the capsule from the camera side in an almost constant direction, the video signal is captured by the cap 20C.
There is a missing part corresponding to a "hangnail" part in the bright part of the opening end face that receives irradiation, or in the dark part of the edge that is in the shadow. The existence of "hangnails" can be determined by the presence of these missing parts,
Moreover, in the sense of highlighting this missing part,
It can be said that enhanced illumination that illuminates the opening end of the cap or illuminates from the opposite direction is superior to uniform diffused illumination from all directions.

[Problem to be solved by the invention]

An object of this invention is to easily determine whether the color combination of the cap and body of a target capsule in a mated state conforms to a standard by performing simple image processing on video signals from a black and white TV camera. To provide a method for inspecting colored capsules, which enables accurate discrimination even under directional highlighting illumination.

[Means to solve the problem]

The method for inspecting colored capsules according to the present invention includes placing a white/black TV camera at a predetermined inspection position to image the side surface of the capsule to be inspected, and applying irradiation light directional in the direction along the axis of the capsule to be inspected. An illumination system capable of illuminating the target capsule is arranged, and within the field of view of the black and white TV camera, one side is parallel to the axis of the capsule at positions corresponding to the cap side and the body side, respectively. A rectangle whose other side exceeds the cap and body diameters is set as each inspection area, and based on the video signals obtained from the black and white TV cameras, each of the cap side and body side inspection areas is By detecting the peak hold value related to the horizontal scan, and then taking the difference between the cap side peak hold value and the body side peak hold value related to the same horizontal scan, the color combination of the capsule to be inspected is determined. The difference signal corresponding to the color combination of the reference capsules is detected, and this difference signal is further processed at a high level threshold set within a predetermined range if the color combination of the reference capsules is different, or if the color combinations of the reference capsules are the same color. are each binarized using a low-level threshold set in a predetermined range to obtain a binarized signal for comparison judgment, and then a high-level one of the binarized signals is obtained. Only the corresponding output is counted over a vertical scanning period corresponding to the inspection area, and it is determined whether the counting result obtained in this way is greater than or equal to an allowable value set in advance according to the reference capsule. By doing so, it is possible to inspect whether the color combination of the cap and body of the capsule to be inspected is in accordance with the standard.

[Effect]

In the colored capsule inspection method according to the invention, (1) peak hold values related to each horizontal scan are detected for each rectangular inspection area set on the cap side and the body side, and the difference between the values is calculated. . The reason why the peak hold value is detected is to eliminate the influence of black or dark-colored characters, marks, etc. printed on the cap or body. (2) Among the differences between the peak hold values on the cap side and the body side in each horizontal scan, the frequency when it is included in the high level setting range corresponding to a unique combination of reference capsules, or a combination of the same color. The number of frequencies included in the low level setting range corresponding to is counted over a vertical scanning period corresponding to the inspection area. (3) Based on whether the counting result is greater than or equal to the preset tolerance value for the reference capsule, it is checked whether the color combination of the cap and body of the capsule to be inspected is in accordance with the standard. be done.
The reason why the counting results were higher than the set allowable value is that strong reflections occur partially on the capsule surface due to the enhanced illumination that is effective for "hangnail" inspection, which is often used in combination, and the difference value of each horizontal scan is Even if there may be some deviation from the set range,
This is to avoid affecting the results of the color combination test.

【Example】

An inspection device that is an application example of the colored capsule inspection method according to the invention will be described below with reference to the drawings. FIG. 1 is a plan view of a peak hold area of a video signal set in a target capsule. The main points of this inspection method are as follows. The side surface of the target colored capsule 20 is imaged with a black and white TV camera. The x and y axes indicate the horizontal and vertical scanning directions of the TV camera. Cap opening end face 20D
sandwich the cap 20C side, body 20B
For example, a rectangular front area U and a rear area V that include each one diameter and have sides parallel to these are set, and within each area U, V, on each one diameter. The difference in the peak hold value of the video signal in the capsule axis direction at each corresponding location is determined. That is, by determining the peak hold value, the influence of printed black or dark-colored characters, marks, etc. is removed. Next, the cap 20C side,
The difference value between each corresponding location on the body 20B side is determined. When the frequency ratio of the difference values included in the range set corresponding to the color combination standard to the whole is equal to or higher than a predetermined value, it is determined that the difference value meets the standard. The above will be explained in detail by giving examples when the cap and body are different colors and when they are the same color. Figure 2 shows various signals when the cap is white and the body is red, and Figure 3 shows various signals when both the cap and body are white, where a is each video signal, b is the difference signal, and c and d are binary signals. FIG. 3 is a schematic diagram of each signal. In Figure 2a, W1 is one vertical scanning period on the same horizontal scanning line expressed using the peak hold value for each horizontal scanning in the front area U of the white cap, and R1 is the rear area V of the red body. each video signal, and its level corresponds to the brightness of the color. The capsule is always bright along the axis, and gets darker toward each end of the diameter, so each video signal forms an upwardly convex curve at the center. In each video signal, a peak-shaped portion located on the right side means that there is a portion where reflection is strong. Note that this partial peak-like portion is taken into consideration so as not to affect the range, as will be described later. K1, K in figure b
2 is the upper and lower threshold for binarization corresponding to the combination standard of a different color of white cap and red body, and G1 and G2 are the same color combination standard of white cap and white body. are each threshold value corresponding to . Figure c is a binary signal when the difference signal between the video signals W1 and R1 is expressed by H for the part within the range of each threshold value K1 and K2, and by L for the part outside the range. . d in the figure shows each video signal W1, R1
This is a binary signal obtained by expressing the difference signal between the threshold values G1 and G2 by H for the portion within the range of each threshold value G1 and G2, and by L for the portion outside the range. Therefore, in figure c,
The H portion occupies most of one vertical scanning period, in other words, it exceeds the setting range not shown in the figure, and in Figure d, the H portion only occupies a small portion within one vertical scanning period. In other words, it is below the set range. Therefore, the cap and body are judged to be a unique combination. In each of the video signals W1 and R1, due to peak-like portions representing areas with strong reflection, H is partially missing in c of the same figure, and H is partially protruding in d of the same figure. Both are small compared to the entire vertical scanning period, and do not affect the final determination. In FIG. 3a, the solid line W1 indicates each video signal for one vertical scanning period in the front region U of the white cap, and the broken line W2 indicates the peak hold value in the capsule axis direction in the rear region V of the white body. It is. K1, K2 and G1, G2 in Figure b are:
These are the same upper and lower thresholds as in FIG. 2b for binarization of the difference signal between the video signals W1 and W2. Figure c shows a binarized signal for each threshold value K1, K2 of the difference signal of each video signal W1, W2, and figure d shows each threshold value G1, G2.
This is a binary signal related to Therefore, Figure c
In this case, the H portion occupies only a small portion within one vertical scanning period, in other words, it is less than the set range.In Figure d, the H portion occupies a large portion within one vertical scanning period; Otherwise, it will exceed the setting range.
Therefore, the cap and body are determined to be a combination of the same color. Incidentally, the peak-like portions in the video signal that represent portions where reflection is strong do not affect the final determination, as in FIG. 2. This means that even under enhanced illumination that has directionality that is effective for "hangnails", the accuracy of color combination determination is not affected by it. The configuration of the inspection device will be explained with reference to FIG. In the figure, a colored capsule 20 to be inspected is inserted into a recess on the outer peripheral surface of the conveying drum 21 with its axis aligned with the circumferential direction of the conveying drum 21, and is conveyed from a supply point (not shown) to an inspection position shown in the figure. be done. This capsule 20 is white from directly above.
An image is taken with a black TV camera 23. As will be described in detail later, the video signal is processed by the image processing circuit 24, and based on the processing result, the judgment circuit 25
Pass/fail judgment is made by Capsule 20 and TV
An illumination unit for imaging is installed between the camera 23 and the camera 23 . This illumination section mainly includes an annular light source 31 of an annular strobe discharge tube, a reflecting member 32 that wraps around the annular light source 31 from the outer periphery and upper side, a lower diffuse transmitting member 32A, and a cylindrical diffuse transmitting member 33. It consists of a diffuse reflection member 34 located on the upper side and having a center hole, and a cylindrical partial light shielding member 35 provided in contact with the outer periphery of the diffuse transmission member 33. Electric power is supplied to the light source 31 from a power source 37, and the timing of the supply is determined by the position detector 22. More specifically, the illumination section includes a light source 31 and a reflecting member 32, as shown in the plan view of FIG.
The diffuser-transmitting member 33 and the partial light-shielding member 35 are arranged concentrically. The diffuse transmission member 33 is the seventh
As shown in the perspective view of the figure, a rectangular arc-shaped hollow portion 33a is provided at the lower right portion of the cylindrical peripheral wall. As shown in the perspective view of FIG. 8, the partial light shielding member 35 has a deep arc-shaped notch 35a in the lower right part of the cylindrical peripheral wall.
However, there is also a shallow arc-shaped notch 35 at the bottom left.
b are provided respectively. In FIG. 5, this illumination unit, in part, allows the capsule 20 to
Diffuse lighting is suitable for determining color combinations and is irradiated almost uniformly from all directions.Secondly, the capsule 20 is illuminated diagonally from above and to the right, almost parallel to the plane formed by the axis of the capsule 20 and the optical axis of the TV camera 23. Composite illumination consisting of two types of illumination is performed: irradiation with directional light suitable for hangnail detection; The image processing circuit 24 and the determination circuit 25 will be explained with reference to a block diagram related to image processing and determination shown in FIG. 4 showing their functions. In the figure, reference numerals 1 and 2 denote peak hold circuits for the front region and the rear region, respectively, which extract the peak hold values of the video signals of the front region U and the rear region V of FIG. 1, respectively. 3 is a differentiator that calculates the difference between each peak hold value in the front region and the rear region. 4, 5, and 8 are comparators each, which compare the magnitude of the two inputs,
If it is positive, it outputs H, and if it is negative, it outputs L. 6 is an AND circuit which outputs H when both inputs are H. 7 is a counter that counts the total duration of a certain state. Here, the comparator 8 corresponds to the determination circuit 25 in FIG. 5, and the other blocks at the previous stage correspond to the image processing circuit 24. The operation illustrated by the block diagram of FIG. 4 is as follows. (1) Each peak hold circuit 1 for the front area and rear area,
2, the video signal and the horizontal synchronization signal are input in parallel, and the front area definition signal is input to the front area peak hold circuit 1, and the rear area definition signal is input to the rear area peak hold circuit 2. Video signals represented by peak hold values for each horizontal scan belonging to the front area U and rear area V in the figure are captured. (Each a in Figures 2 and 3
(2) The difference between the peak hold values for each horizontal scan of each region U and V is determined by the subtractor 3. (Refer to each b in Figures 2 and 3.) (3) Of these difference values, only those smaller than the upper threshold are passed to the comparator 4, and only those larger than the lower threshold are passed to the comparator 4. 5, it is output as a signal H. By the following AND circuit 6,
Only when the signal H is output from each comparator 4, 5, that is, only the difference values that are within the upper and lower threshold ranges are output as the signal H (tolerance value signal). . Note that the tolerance signal is
This means that it is an acceptable signal to be regarded as the same as the color combination standard. (Fig. 2, 3
(See each c and d in the figure) (4) This tolerance signal, both the vertical synchronization signal and the clock signal, is input to the counter 7, and the total period of the tolerance value state in one vertical scanning period, that is, the tolerance value period, is calculated. It will be done. (5) The comparator 8 compares this allowable value period with a period threshold value, which is a standard for determining pass/fail, and outputs a pass determination signal only when it is greater than or equal to this threshold value.

【Effect of the invention】

The colored capsule inspection method according to the invention has the following effects. (1) Since it uses a black and white TV camera to capture images, it is easier to process for inspection than the conventional color TV camera.
Cost reduction can be achieved. (2) The accuracy of color combination judgment is not affected by the emphasis lighting method, so the diffuse lighting method is effective for color combination judgment, and the emphasis lighting method is effective for inspecting "hangnails." By using a combined illumination method, it is possible to perform an accurate inspection that is compatible with the inspection for hangnails, and the overall efficiency of capsule inspection can be improved. (3) By taking the peak hold value of the video signal in the direction of the capsule axis within each area set on the cap side and the body side, the influence of printed black or dark-colored characters and marks is removed. This will help improve the reliability of the original color combination inspection.

[Brief explanation of drawings]

Figure 1 is a plan view of the peak hold area of the video signal set in the target capsule, and Figure 2 shows various signals when the cap is white and the body is red, where a is each video signal, b is the difference signal, c , d are schematic diagrams of each binary signal, Figure 3 shows various signals when both the cap and body are white, a is each video signal, b is the difference signal, c and d are the binary signals. Each schematic diagram, FIG. 4 is a block diagram related to image processing and judgment of an inspection device which is an application example of the invention method, FIG. 5 is a configuration diagram of the inspection device, and FIG. 6 is a plan view of the illumination section of the inspection device. , FIG. 7 is a perspective view of the diffusing and transmitting member of the inspection device,
FIG. 8 is a perspective view of a partial light shielding member of the inspection device;
The figures relate to the capsule, a is a side view of the cap, b
Side view of the body, c is a side view of the pre-fitted state, d
10 is a side view of the final fitted state, FIG. 10 is a cross-sectional view of the capsule, b is a plan view of the capsule, and FIG. 11 is a hangnail state of the capsule with the cap side cut. Concerning the capsule, a is its cross-sectional view, b is its plan view, and Fig. 12 is related to conventional diffuse illumination, a is a side view of the capsule, b is a schematic diagram of the video signal when different colors are used, and c is a schematic diagram of the video signal when the colors are the same. FIG. 13 is a schematic diagram of a video signal during emphasized illumination in a conventional example, where a is a side view of a capsule, b is a schematic diagram of a video signal when different colors are used, and c is a schematic diagram of a video signal when the colors are the same. Code explanation, 1: Front region peak hold circuit,
2: Rear area peak hold circuit, 3: Differentiator,
4, 5: Comparator, 6: AND circuit, 7: Counter,
8: Comparator, 20: Capsule, 20B: Body,
20C: Cap, 20D: Cap opening end surface.

Claims (1)

[Scope of Claims] 1. A method for inspecting whether the color combination of the cap and body of a capsule to be inspected in a fitted state conforms to a standard, which method comprises placing the capsule to be inspected at a predetermined inspection position in advance. A white/black TV camera that images the side surface of the target capsule and an illumination system capable of irradiating the target capsule to be inspected with irradiation light with directionality in the direction along the capsule axis are arranged, and the white/black TV camera Within the field of view of the camera, a rectangle with one side parallel to the axis of the capsule and the other side exceeding the respective diameters of the cap and body is set as each inspection area at a position corresponding to the cap side and body side. Then, based on the video signals obtained from the white and black TV cameras, detect the peak hold values related to each horizontal scan in the cap side and body side inspection areas, and then detect the peak hold values related to the same horizontal scan. By taking the difference between the cap side peak hold value and the body side peak hold value, a difference signal corresponding to the color combination of the capsule to be inspected is detected, and this difference signal is then used to calculate the difference signal between the color combination of the reference capsule. If the combination is a different color, it is binarized using a high-level threshold set in a predetermined range, and if it is the same color, it is binarized using a low-level threshold set in a predetermined range. Particularly, after obtaining a binary signal for comparison and determination, only an output corresponding to a high level is counted among the binary signals over a vertical scanning period corresponding to the inspection area. The color combination of the cap and body of the capsule to be inspected meets the standard by determining whether the counting result obtained in this way is greater than or equal to the preset tolerance value for the reference capsule. A method for inspecting colored capsules, characterized by inspecting whether or not