JPH1172440A - Method and apparatus for visual inspection of stamped tablet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method and an apparatus for visual inspection of stamped tablets whereby stamped tablets filled in a pocket part of a blister sheet being transferred can be inspected in a blister sheet package machine in an inspection process wherein stamps on surfaces of tablets are not distinguished from a foreign article, etc. SOLUTION: One-dimensional image data of the whole surface of a stamped tablet is binarized for every pixel of a CCD camera (S3). It is detected whether or not a total count PS of pixels of one value (dark part) is between a minimum reference count PMIN and a maximum reference count PMAX (S9). It is also checked whether a length of a short side BS of a circumscribed rectangle to all pixels of the one value (dark part) is not smaller than a short side reference value LMIN, and at the same time a length of a long side BL of the circumscribed rectangle is not larger than a long side reference value LMAX (S11). The stamped tablet is visually inspected in this manner.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for inspecting the appearance of a stamped tablet for examining the appearance of a stamped tablet, and more particularly to a method implemented in a blister sheet packaging machine.

[0002]

2. Description of the Related Art Conventionally, in a method for inspecting the appearance of a stamped tablet, which inspects the appearance of the stamped tablet, the stamped portion of the tablet surface is distinguished from other portions so that the stamped surface of the tablet is not judged as a foreign substance. The appearance of the tablets was inspected. For example, in the tablet appearance inspection method described in JP-A-6-258226, a symbol printed on the tablet surface is used for a video signal obtained by imaging the tablet surface with a two-dimensional imaging device. Is set, and the symbol inspection window is equally divided into a plurality of unit dots, and the binarized data obtained by binarizing the unit dots into a light portion and a dark portion is shown below. By processing as described, the symbol printed on the tablet is not determined as a foreign substance.

[0003] That is, while a plurality of unit dots to be inspected are set as inspection dots from among the unit dots in the symbol inspection window, whether each inspection dot is a bright portion or a dark portion in the case of a non-defective product is determined. Is set in advance, and the binarized data of each inspection dot in the symbol inspection window is compared with the binarized non-defective data corresponding to the inspection dot. When the value was larger than the predetermined allowable value, it was determined that there was a defect in the appearance in the symbol inspection window. Therefore, the symbol printed on the tablet was not determined as a foreign substance, and the foreign substance of the tablet could be detected in the symbol inspection window including the symbol printed on the surface of the tablet.

When comparing the binarized data of each inspection dot in the symbol inspection window with the binarized non-defective data corresponding to the inspection dot, the binarized data of the inspection dot corresponds to the inspection dot. Even if it does not match the binarized non-defective data, if it matches any of the binarized data of the four upper, lower, left, and right unit dots adjacent to the test dot, the binarized data of the test dot will Is considered to match the binarized non-defective data corresponding to, and even if the symbol printed on the surface of the tablet becomes slightly thicker or thinner, it is determined that the tablet appearance is defective. Because there was no, it was possible to properly inspect the shape defect of the symbol printed on the tablet surface.

In addition to the standard posture of the tablet, binarized non-defective data of each inspection dot is set for a plurality of inclined postures rotated by a predetermined angle from the standard posture.
When comparing the binarized data of each inspection dot in the symbol inspection window with the binarized non-defective data corresponding to the inspection dot, the number of inspection dots that do not match the binarized non-defective data in any one posture Is smaller than a predetermined allowable value, it is determined that there is no defect in the appearance in the symbol inspection window. Therefore, even if the tablet is slightly inclined from the standard posture, the appearance defect in the symbol inspection window can be inspected.

[0006]

However, the tablet appearance inspection method described in Japanese Patent Application Laid-Open No. 6-258226 discloses a two-dimensional image data obtained by imaging the surface of a tablet with a two-dimensional imaging device. Based on the above, set the symbol inspection window, specify the inspection dot, specify four unit dots above, below, left and right adjacent to the inspection dot, identify and compare binarized non-defective data corresponding to the inspection dot, standard posture and multiple inclinations Performs processing such as identifying and comparing binarized non-defective data on posture, and is called “pattern matching”.
The appearance inspection is performed by using the method described above, so that the efficiency of the inspection processing is not originally good.

Using such a tablet appearance inspection method,
When trying to inspect the appearance of the tablets filled in the pockets of the blister sheet during transportation in the blister sheet packaging machine, the blister sheet packaging machine fills the tablets in the pockets of the blister sheet at a packaging speed of about 6,000 tablets / minute or more. As a result, the inspection process is greatly delayed from the packaging process of the blister sheet packaging machine, and the packaging ability of the blister sheet packaging machine cannot be effectively utilized.

Further, since the symbol on the surface of the tablet filled in the pocket portion of the blister sheet is oriented in an arbitrary direction, it is necessary to prepare binarized non-defective data for any inclined posture and compare it with each inspection dot. If you can't
The effectiveness of visual inspection cannot be obtained. That is, it was impossible to perform an appearance inspection on a tablet having a symbol printed on its surface using a so-called “pattern matching” technique in a blister sheet packaging machine.

In order to solve the above-mentioned problem, the area calculated by combining symbols and foreign substances printed on the surface of the tablet into a single unit is reduced by making the symbols printed on the surface of the tablet slightly thicker or thinner. In addition to comparing with the area range considered as non-defective, the circumscribed shape that collectively measures symbols and foreign substances printed on the tablet surface, and the symbol printed on the tablet surface in any direction If you perform a visual inspection of the tablet without distinguishing the symbols printed on the tablet surface from foreign substances, etc., compared to the shape range considered to be good even if it is oriented, it may be affected by the direction of the symbols on the tablet surface In addition, the efficiency of the inspection process can be made very good. Therefore, the appearance inspection of the tablet having the symbol printed on the surface can be performed in the blister sheet packaging machine.

Accordingly, the present invention has been made to solve the above-mentioned problems, and an inspection process is performed without distinguishing a stamp on the surface of a tablet from a foreign substance or the like, so that a blister sheet being conveyed is conveyed. It is an object of the present invention to provide a method for inspecting the appearance of a stamped tablet and an apparatus for inspecting the appearance of a stamped tablet that can inspect the appearance of a stamped tablet filled in a pocket portion in a blister sheet packaging machine.

[0011]

According to a first aspect of the present invention, there is provided a method for inspecting the appearance of a stamped tablet, wherein the method comprises the steps of:
The appearance of the stamp tablet is inspected by binarizing the image data of the entire surface of the stamp tablet for each pixel and determining whether or not the circumscribed shapes of all pixels of one value are within the first reference range. It is characterized by doing.

According to a second aspect of the present invention, there is provided a method for inspecting the appearance of an imprinted tablet, wherein the image data of the entire surface of the imprinted tablet is binarized for each pixel and is constituted by pixels of one value, and is not less than a certain value. The appearance of the stamp tablet is inspected by determining whether or not the circumscribed shapes for all the connection regions having the size of are within the first reference range.

According to a third aspect of the present invention, there is provided a method for inspecting the appearance of a stamped tablet according to the first or second aspect, wherein the total number of one of the values for all pixels is the second. It is characterized in that the appearance of the stamp is inspected by judging whether or not it is within the reference range.

According to a fourth aspect of the present invention, there is provided a method for inspecting the appearance of a stamped tablet according to the first or second aspect, wherein the method comprises a pixel of one value. The appearance of the stamp is inspected by also determining whether or not the total number of pixels of all connected regions having a size equal to or greater than a certain value is within the second reference range.

According to a fifth aspect of the present invention, there is provided a method for inspecting the appearance of a stamped tablet according to any one of the first to fourth aspects, wherein the first reference range is a probability range. It is characterized by being statistically calculated. Further, the method for inspecting the appearance of a stamped tablet according to claim 6 comprises:
5. The method for inspecting the appearance of a stamped tablet according to claim 3, wherein the second reference range is calculated stochastically. 6.

According to a seventh aspect of the present invention, there is provided a method for inspecting the appearance of a stamped tablet according to any one of the first to sixth aspects, wherein the circumscribed shape is rectangular. It is characterized by the following.

According to an eighth aspect of the present invention, there is provided the method for inspecting the appearance of a stamped tablet according to the seventh aspect, wherein the object of the first reference range is a long side and a short side of the rectangle. It is characterized by being. According to a ninth aspect of the present invention, there is provided the method for inspecting the appearance of a stamped tablet according to the seventh aspect, wherein the object of the first reference range is the diagonal line of the rectangle. . According to a tenth aspect of the present invention, there is provided the method for inspecting the appearance of a stamped tablet according to the seventh aspect, wherein the object of the first reference range is the area of the rectangle. .

According to a eleventh aspect of the present invention, there is provided a method for inspecting the appearance of a stamped tablet according to any one of the first to tenth aspects. It is characterized in that the appearance of the stamp tablet filled in the section is inspected in a blister sheet packaging machine.
According to a twelfth aspect of the present invention, there is provided a stamped tablet appearance inspection apparatus that implements the stamped tablet appearance inspection method according to any one of the first to eleventh aspects.

In the method and apparatus for inspecting the appearance of a stamped tablet according to the present invention having the above-described configuration, the image data of the entire surface of the stamped tablet is binarized for each pixel to obtain the surface of the stamped tablet. The whole is grasped by binarized pixels. Here, the stamp on the surface of the tablet is grasped by a pixel of one value equal to a foreign substance, and the circumscribed shape (for example, a rectangle) of all the pixels of the one value is measured and the one value is measured. Are calculated.

On the other hand, the entire surface of the stamp tablet having no appearance defect is similarly grasped in advance by binarized pixels, and the circumscribed shapes of all the pixels of one value at this time are measured. And use it as the basis for the appearance inspection of stamped tablets. However, the first reference range has a certain width so that the appearance inspection can be performed even when the seal is oriented in an arbitrary direction. Further, the total number of pixels of one value at this time is calculated and used as a reference for the appearance inspection of the stamp. However, since slight bleeding or rubbing of the seal should be allowed, the second reference range is set to have a certain width.

After the appearance inspection results of the same type of stamped tablet have been accumulated to some extent, the already performed appearance inspection results (the population of the circumscribed shape for all pixels of one value,
The first reference range or the second reference range may be determined by statistically processing the population of the total number of pixels of one value).

Then, it is determined that the circumscribed shapes of all the pixels of one value are within the first reference range,
If it is determined that the total number of pixels of one value is within the second reference range, it is determined that the stamping state on the tablet surface is within the allowable range, and that there is no foreign matter on the tablet surface, and the stamping tablet to be inspected is Is determined to have no appearance defect. If it is determined that the circumscribed shape for all pixels of one value is not within the first reference range, or if the total number of pixels of one value is not within the second reference range, the surface of the tablet Is not in the acceptable range, there are foreign substances on the tablet surface, or
Based on both, it is determined that the stamp tablet to be inspected has defective appearance. In addition, if all the connected regions that are constituted by pixels of one value and have a size smaller than a certain value are excluded from the circumscribed shape and the total number, the error factors such as noise are removed. be able to.

Therefore, unlike the so-called “pattern matching” method used in the prior art, the marking direction on the surface of the tablet to be inspected does not affect the appearance inspection.
Further, the efficiency of the inspection process is very good.

That is, since the method for inspecting the appearance of a stamped tablet and the apparatus for inspecting the appearance of a stamped tablet according to the present invention perform the inspection process without distinguishing the stamping on the tablet surface from foreign substances, etc. The efficiency of the inspection process can be greatly improved without being affected by the direction. Therefore, according to the method for inspecting the appearance of a stamped tablet of the present invention, the appearance of the stamped tablet filled in the pocket of the blister sheet being conveyed can be inspected in the blister sheet packaging machine.

In addition, since the inspection process is performed by grasping the stamp on the surface of the tablet with a pixel of one value equal to that of a foreign substance or the like, the object of the appearance inspection is not limited to the stamp tablet. Therefore, any tablet that can be normally imaged can be subjected to the appearance inspection.

In addition, by removing a connection area having a size smaller than a certain value from the object of the visual inspection to remove error factors such as noise from the visual inspection of the imprint tablet, a reliable visual inspection of the imprint tablet can be performed. It can be carried out.

If the first reference range and the second reference range, which are the basis of the visual inspection of the stamped tablet, are determined by processing the results of the already performed visual inspection stochastically, reliable stamping can be performed. A visual inspection of the tablet can be performed.

[0028]

Embodiments of the present invention will be described below with reference to the drawings. In the present embodiment, as shown in FIG. 2, a visual inspection device 1 which is a visual inspection device for a stamped tablet.
By equipping the blister sheet packaging machine 30 with
The method for inspecting the appearance of the stamped tablet is performed in the blister sheet packaging machine 30.

First, a brief description will be given of the blister sheet packaging machine 30 in which the method for inspecting the appearance of a stamped tablet is carried out. The blister sheet packaging machine 30 automatically packages tablets and the like into blister sheets. Specifically, first, a container film 40 such as PP or PVC is fed into a heating plate 50 and a forming plate 51 by a film feed roll 33 and tension rolls 31 and 32, and a pocket portion 44 (see FIG. 3) is formed into a container film 40. Then, when the container 41 formed with the pocket portion 44 (see FIG. 3) in the container film 40 is sent below the tablet input shutter 52, the tablet input shutter 5
2 automatically fills each pocket 44 (see FIG. 3) with a tablet or the like. Here, the stamp tablet 1 shown in FIG. 5 is filled in each pocket 44 (see FIG. 3).

Further, an aluminum cover film 42 is fed via tension rolls 34 and 35 onto a container film 41 in which each pocket portion 44 (see FIG. 3) is filled with the stamp tablet 1, and a pair of seal rolls is provided. Fix at 36. As a result, a film-like blister sheet 43 in which the stamp tablet 1 (see FIG. 5) is filled in each pocket 44 (see FIG. 3) is manufactured. After the film-shaped blister sheet 43 is cut into a sheet shape, it is sequentially sent to a defective sheet discharging mechanism, a blister sheet stacking mechanism, and the like (not shown).

Next, the appearance inspection apparatus 10 for implementing the appearance inspection method for a stamped tablet will be described with reference to the block diagram of FIG. The visual inspection device 10 includes an A / D converter 13, a comparator 14, an image memory 16, a shading correction table 18, a CPU 20, a determination memory 22, an input / output interface 23, a visual inspection result and statistical data memory 24, a camera timing control unit. 26 and the like.

The A / D converter 13 converts one-dimensional image data captured by the CCD camera 11 from an analog signal to a digital signal. Here, the CCD camera 11 will be described. As shown in FIG.
The blister sheet 43 is illuminated with the second light 13 and the blister sheet 43 is one-dimensionally imaged in the width direction. Therefore, a plurality of pockets 44 formed in one row in the width direction of the blister sheet 43 and the tablet 1 filled in each pocket 44 can be simultaneously imaged. At this time, since the image of the blister sheet 43 in close contact with the fixed roll 37 is imaged, the film-shaped blister sheet 43 does not swing and adversely affect the imaging. Note that C
The CD camera 11 and the lighting 12 are depicted in the blister sheet packaging machine 30 in FIGS. 2 and 3, but are one of the components of the visual inspection device 10.

Returning to FIG. 4, the comparator 14 binarizes the one-dimensional image data, which has been replaced by a digital signal, with a specific threshold value. Since the one-dimensional image data is captured by the CCD camera 11, it is binarized for each pixel of the CCD camera 11. Also,
The threshold used by the comparator 14 can be changed according to the inspection conditions. The image memory 16 stores the one-dimensional image data binarized by the comparator 14. Shading correction table 18
Stores a threshold value t used when the one-dimensional image data is binarized by the comparator 14.
Note that there is a technical limit in uniformly illuminating the entire blister sheet 43 with the light 13 of the illumination 12, and thus the threshold value t is corrected for shading.

The CPU 20 executes a flowchart shown in FIG. 1 to be described later, and executes it by using the determination memory 22 and the like. The input / output interface 23 is for transmitting or receiving a control signal to or from the blister sheet packaging machine 30. Thereby, for example, a defective sheet discharging mechanism of the blister sheet packaging machine 30 can be controlled. It is also for transmitting display data to the monitor 25, and can display one-dimensional image data, a visual inspection result, and the like on the monitor 25. Although the monitor 25 is illustrated outside the appearance inspection device 10 in FIG. 4, it is one of the components constituting the appearance inspection device 10.

Visual inspection result and statistical data memory 24
Stores the appearance inspection result data and statistical data (see FIG. 8) obtained by probabilistically processing the appearance inspection result data. These visual inspection result data and statistical data are
It can be displayed on the monitor 25. Further, a control signal can be transmitted to the blister sheet packaging machine 30 based on the appearance inspection result data and the statistical data.

The camera timing control means 26 includes a CCD
The one-dimensional image data captured by the camera 11 is converted into A / D
It controls the timing to be taken into the converter 13. Such timing is performed based on a signal from an encoder (not shown) provided in the blister sheet packaging machine 30.

Next, the procedure of the method for inspecting the appearance of a stamped tablet will be described.
Description will be made based on the flowchart of FIG. First, in step (hereinafter, abbreviated as “S”) 1, a CCD
The one-dimensional image data captured by the camera 11 is fetched, and in S2, the one-dimensional image data is
The D converter 13 converts the analog signal into a digital signal. Then, in S3, the one-dimensional image data converted into the digital signal is compared with the threshold value t stored in the shading correction table 18 by the comparator 1.
4 is binarized.

For example, as shown in FIG.
When the one-dimensional image data captured by the camera 11 corresponds to the imaginary line A applied to the seal tablet 1, the luminance gradation of the one-dimensional image data corresponding to the imaginary line A is as shown in FIG. At this time, the one-dimensional image data corresponding to the imaginary line A among the marking portions 3, 4, 5, and 6 on the surface 2 of the marking tablet 1 and the foreign matter 7 attached to the surface 2 of the marking tablet 1 In FIG. 6 showing the brightness gradation of the one-dimensional image data, a part A3 corresponding to a part of the stamped part 3 has a lower brightness, and the other part (the surface of the stamped tablet 1) has been captured. 2) is displayed brightly. Then, by performing binarization with the threshold value t in S3, a portion A corresponding to a part of the stamped portion 3 is obtained.
3 is binarized to one value indicating a dark part, and the other part (a part corresponding to the surface 2 of the stamp tablet 1) is binarized to the other value indicating a light part. The binarization is performed for each pixel of the CCD camera 11.

In step S4, the binarized one-dimensional image data is accumulated in the image memory 16, and the entire surface 2 of the stamp 1 is grasped by binarized pixels. Next, in S5, for the connected region formed by the pixels of one value (dark portion), the value of the pixel having the number of pixels smaller than the noise reference number P, which is a constant value, is changed to the value of one value ( From the dark part) to the other value (light part). Thereby, the image memory 1 for grasping the entire surface 2 of the stamp tablet 1
From the binarized image of No. 6, minute noise generated by various causes is removed.

Then, in S6, the largest number M of pixels of the connected area is obtained from the binary image in the image memory 16, and in next S7, the number M of pixels is compared with the noise reference number P. If the number of pixels M is less than the noise reference number P (S7: Yes), the process proceeds to S12, and the imprinting tablet 1 imaged by the CCD camera 11 in S1 is determined to be good. This is because when tablets that are not stamped (for example, tablets that are not stamped on one side) are mixed, tablets that are not stamped (or tablets that are not stamped) that do not have a bad appearance have a CCD. This is because when the image is taken by the camera 11, it is determined to be a non-defective product. On the other hand, if the number M of pixels is not less than the noise reference number P (S7: No), the process proceeds to S8.

Next, in S8, by counting the pixels of one value (dark part) accumulated in the image memory 16, the marking portions 3, 4, 5, and 5 on the surface 2 of the marking tablet 1 are counted.
6 and the total number PS of pixels corresponding to the foreign matter 7 attached to the surface 2 of the stamp tablet 1 and the like.

Then, in S9, the minimum reference number PMI
It is determined whether there is a total number PS between N and the maximum reference number PMAX. Note that the minimum reference number PMIN is changed to the maximum reference number P
Between MAX corresponds to a second reference range. Minimum reference number PM
If there is no total number PS between IN and the maximum reference number PMAX (S9: No), the process proceeds to S13, and the stamp tablet 1 captured by the CCD camera 11 in S1 is determined to be defective. On the other hand, when the total number PS is between the minimum reference number PMIN and the maximum reference number PMAX (S9: Yes), the process proceeds to S10.

Next, in S10, a rectangle circumscribed shape (hereinafter, referred to as "circumscribed rectangle") B for all pixels of one value (dark portion) accumulated in the image memory 16 is measured, and the circumscribed rectangle B is measured. Of the long side BL and the short side BS are determined. For example, when the binarized image in the image memory 16 is as shown in FIG. 7, the marking portions 3, 4, 5, and 6 on the surface 2 of the marking tablet 1 and the foreign matter adhered to the surface 2 of the marking tablet 1 The circumscribing rectangle B is measured for all pixels having one value (dark portion) corresponding to 7 and the lengths of the long side BL and the short side BS of the circumscribing rectangle B are determined by the number of pixels.

In S11, it is determined whether or not the length of the short side BS is equal to or longer than the short side reference value LMIN and the length of the long side BL is equal to or shorter than the long side reference value LMAX.
That is, it is determined whether or not the circumscribed rectangle B measured in S10 is within the first reference range. As described above, the first reference range is set to be equal to or longer than the short side reference value LMIN and the long side reference value LM.
AX is defined below so that the appearance inspection method of the imprinted tablet is not affected by the direction of imprinting on the surface of the imprinted tablet 1. Therefore, the short-side reference value LMIN and the long-side reference value LMAX are determined in consideration of all the inclination postures of the stamp 1.

If the length of the short side BS is equal to or longer than the short side reference value LMIN and the length of the long side BL is equal to or shorter than the long side reference value LMAX (S11: Yes), the process proceeds to S12.
The stamp tablet 1 imaged by the CCD camera 11 in S1 is determined to be non-defective. On the other hand, the length of the short side BS is equal to the short side reference value LMIN.
Or the length of the long side BL is longer than the long side reference value LMA.
If it is not less than or equal to X (S11: No), the process proceeds to S13, and the stamp tablet 1 imaged by the CCD camera 11 in S1 is determined to be defective.

In this way, the procedure of the method for inspecting the appearance of the stamped tablet is advanced.
Since a plurality of stamps 1 arranged in a line in the width direction of the blister sheet 43 are simultaneously imaged, the above-described S1 to S13
Is performed simultaneously with respect to each of the stamps 1 arranged in a line in the width direction of the blister sheet 43. Further, as described above, instead of examining the correlation such as the so-called “pattern matching” used in the prior art, the image memory 1
Since the simple processing of comparing the total number PS of the pixels of one value (dark part) accumulated in 6 or comparing the circumscribed rectangle B for all the pixels of one value (dark part) is used, The inspection process becomes very fast, and can sufficiently cope with the packaging speed of the blister sheet packaging machine 30 of 6000 tablets / min or more.

The above-described noise reference number P, minimum reference number PMIN, maximum reference number PMAX, and short-side reference value LMI
N and the long side reference value LMAX are stored in the determination memory 22 in advance with the number of pixels. For example, the noise reference number P
"10", "430" as the minimum reference number PMIN, "530" as the maximum reference number PMAX, and the short-side reference value LMIN.
"15" and "40" as the long side reference value LMAX. In particular, minimum reference number PMIN, maximum reference number PMA
Regarding X, the short side reference value LMIN, and the long side reference value LMAX, the entire surface of the stamp tablet 1 having no defective appearance is imaged by the CCD camera 11 and grasped in advance by binarized pixels. The determination is made based on the total number of pixels of one value (dark part) at that time.

As described in detail above, the appearance inspection method of the stamped tablet and the appearance inspection apparatus 1 of the stamped tablet according to the present embodiment.
In the case of 0, the entire one-dimensional image data of the surface 2 of the imprinting tablet 1 is binarized for each pixel of the CCD camera 11 (S3). (S4). Here, for example, in the imprint tablet 1 of FIG. 5, the imprint portions 3, 4, 5, and 6 on the surface 2 of the imprint tablet 1 are grasped by the pixels of one value (dark portion) equal to the foreign matter 7 and the like. , The total number PS of the pixels of the one value (dark portion) is calculated and (S
8) The circumscribed rectangle B is measured for all the pixels of the one value (dark part) (S10, see FIG. 7).

On the other hand, the entire surface 2 of the imprinted tablet 1 having no defective appearance is similarly grasped in advance by binarized pixels, and the pixels of one value (dark portion) at this time are obtained. The total number PS is calculated and used as a reference for the appearance inspection of the stamp tablet 1. However, slight bleeding or rubbing of the seal should be allowed.
To the maximum reference number PMAX (S7). Further, the circumscribed rectangle B for all the pixels of one value (dark part) at this time is measured and used as a reference for the appearance inspection of the stamp tablet 1. However, such a standard is given a width so that the appearance inspection can be performed even when the seal is oriented in an arbitrary direction, and is equal to or less than a long side reference value LMAX with respect to the long side BL of the circumscribed rectangle B.
And a short-side reference value LM for the short side BS of the circumscribed rectangle B
IN or more (S11).

After the appearance inspection results of the same type of imprinted tablet 1 have been accumulated to some extent, the appearance inspection results that have already been performed (the population of the total number of pixels of one value (dark portion) or one value) By statistically processing the population of circumscribed rectangles for all pixels in the (dark portion), more accurate minimum reference number PMIN, maximum reference number PMAX, short-side reference value LMIN, and long-side reference value LMAX are obtained. It can also be determined.

For example, the appearance inspection result and the appearance inspection result (population of the total number PS of pixels of one value) stored in the statistical data memory 24 are statistically processed as shown in FIG. The reference number PMIN and the maximum reference number PMAX are
Determined by the average value and standard deviation σ. At this time, since the probability statistical processing can be performed for each position of the pocket portion 44 of the blister sheet 43, the minimum reference number PMIN and the maximum reference number PMAX can be determined for each position of the pocket portion 44 of the blister sheet 43. it can. As a result, it is possible to further suppress inspection errors caused by the fact that the entire blister sheet 43 cannot be uniformly illuminated with the light 13 of the illumination 12. Further, the short-side reference value LMIN and the long-side reference value LMAX can be similarly determined.

Then, it is determined that the total number PS of the pixels of one value (dark part) is between the minimum reference number PMIN and the maximum reference number PMAX (S9: Yes), and the value PS of one value (dark part) is determined. The length of the short side BS of the circumscribed rectangle B for all pixels is equal to or longer than the short side reference value LMIN, and the length of the long side BL of the circumscribed rectangle B is the long side reference value LMA.
If it is determined to be X or less (S11: Yes), it is determined that the printing state of the surface 2 of the printing tablet 1 is within the allowable range and that there is no foreign matter 7 on the surface 2 of the printing tablet 1, and the printing of the inspection target is performed. It is determined that the tablet 1 has no appearance defect (S12).

The total number P of pixels of one value (dark portion)
It is determined that S is not between the minimum reference number PMIN and the maximum reference number PMAX (S9: No), or the length of the short side BS of the circumscribed rectangle B for all pixels of one value (dark portion) is short. If it is determined that the length is not more than the side reference value LMIN, or if the length of the long side BL of the circumscribed rectangle B is not less than the long side reference value LMAX (S11: No), the printing state of the front surface 2 of the printing tablet 1 is allowable. It is determined that it is out of the range, that there is a foreign substance 7 on the surface 2 of the stamp tablet 1, or that both are both, and that the stamp tablet 1 to be inspected has a poor appearance (S13).

Note that, for all connected regions which are composed of pixels of one value (dark portion) and have a size smaller than the noise reference number P, the values of those pixels are changed to one value (dark portion). ) To the other value (bright portion) (S5), and is excluded from the targets of the total number PS and the circumscribed rectangle B, so that error factors such as noise can be removed.

Therefore, since it is different from the so-called "pattern matching" technique used in the prior art, the marking direction on the surface 2 of the tablet 1 to be inspected does not affect the appearance inspection. The efficiency is also very good.

That is, the method for inspecting the appearance of a stamped tablet and the apparatus for inspecting the stamped tablet appearance 30 of the present invention inspect the stamped portions 3, 4, 5, and 6 on the surface 2 of the stamped tablet 1 without distinguishing them from the foreign matter 7 or the like. Since the processing is performed, the efficiency of the inspection processing can be greatly improved without being affected by the directions of the marking portions 3, 4, 5, and 6 on the surface 2 of the marking tablet 1. Therefore,
The appearance of the stamp tablet 1 filled in the pocket portion 44 of the blister sheet 43 being transported can be inspected in the blister sheet packaging machine 30 by the stamp tablet appearance inspection method of the present embodiment.

Further, the stamped portion 3 on the surface 2 of the stamped tablet 1
The inspection process is performed by grasping the pixels 4, 5, and 6 with the pixel of one value (dark portion) equal to the foreign matter 7 or the like (S1 to S13).
The target of the appearance inspection is not limited to the stamp tablet 1.
Therefore, any tablet that can be normally imaged can be subjected to the appearance inspection.

Also, by removing the connected area having a size smaller than the noise reference number P from the object of the visual inspection (S
5) Since the error factors such as noise are removed from the appearance inspection of the stamp tablet 1, the appearance inspection of the stamp tablet 1 can be performed reliably.

Further, by processing the results of the already performed appearance inspection stochastically, the minimum reference number PMIN, maximum reference number PMAX,
If the short-side reference value LMIN and the long-side reference value LMAX are determined, a reliable appearance inspection of the stamp tablet 1 can be performed.

The present invention is not limited to the above embodiment, and various changes can be made without departing from the gist of the present invention. For example, in the above embodiment, S1
In S11, it is determined whether or not the circumscribed rectangle B measured at 0 is within the first reference range.
It is determined whether the length of S is equal to or greater than the short side reference value LMIN and the length of the long side BL of the circumscribed rectangle B is equal to or less than the long side reference value LMAX. May be determined based on the length, area, and the like.

In S10 and S11, the circumscribed rectangle B for all pixels of one value (dark portion) is measured to determine whether or not it is within the first reference range. Measure the circumscribed circle for all the pixels in
It may be determined whether or not it is within the reference range. At this time,
The determination as to whether or not it is the first reference range is performed using the outer diameter, inner diameter, outer circumference, area, or the like of the circumscribed circle. Alternatively, the circumscribed polygon for all the pixels of one value (dark portion) may be measured to determine whether the value is within the first reference range. At this time, the determination as to whether or not the range is the first reference range is performed using the length of the long diagonal line, the length of the short diagonal line, and the like of the circumscribed polygon.

The total number P of pixels of one value (dark portion)
After calculating S and judging whether or not it is within the second reference range (S8, S9), the circumscribed rectangle B for all pixels of one value (dark part) is measured and is within the first reference range. (S10, S11), the order of these determinations is reversed to determine whether the circumscribed rectangle B for all pixels of one value (dark portion) is within the first reference range. After the determination, it may be determined whether or not the total number PS of pixels of one value (dark portion) is within the second reference range.

The front side 2 and the back side are present on the front side 2 of the stamp tablet 1. However, when the front side and the back side are differently stamped, or when only one of the front side and the back side (one side) is stamped. Is the minimum reference number PMIN that is used for both the front and back sides so that the appearance inspection of the stamping tablet 1 can be performed without any trouble even if the CCD camera 11 takes an image of the front side or the back side of the front surface 2 of the stamping tablet 1. , Maximum reference number PMAX,
The short side reference value LMIN and the long side reference value LMAX are determined.
In particular, in the blister sheet packaging machine 30, it is difficult to fill the pocket 44 of the blister sheet 43 while aligning the front surface 2 of the stamp tablet 1 with the front side or the back side.
Regardless of whether the CCD camera 11 takes an image of the front side or the back side of the front surface 2 of the marking tablet 1, it is effective that the appearance inspection of the marking tablet 1 can be performed without any trouble.

In the above embodiment, the inspection process is performed based on the one-dimensional image data picked up by the CCD camera 11, which is a one-dimensional image pickup device.
S13) It can be performed based on two-dimensional image data captured by a CCD camera, which is a two-dimensional imaging device. At this time, the blister sheet 4 is included in the two-dimensional image data imaged by the CCD camera, which is a two-dimensional imaging device.
3 as well as a plurality of stamped tablets 1 arranged in the length direction of the blister sheet 43 as well as a plurality of stamped tablets 1 arranged in the width direction.
Step 13 can be performed simultaneously for each stamp tablet 1 arranged in a certain area of the blister sheet 43. still,
The one-dimensional image data used in the above embodiment has a smaller pixel size than the two-dimensional image data.
High-performance appearance inspection can be realized under high-speed inspection processing.

Although the CCD camera 11 is a camera using a solid-state image element, an inspection process can be performed based on image data taken by a conventional camera using an image pickup tube. However, since there is no pixel segment in the image data, the binarization process performed in S3 is performed for each pixel in the image memory 16.

The CCD camera 11 not only captures images of a plurality of stamps 1 (the pockets 44 of the blister sheet 43) arranged in a line in the width direction of the blister sheet 43, but also captures the sheet portion of the blister sheet 43. At the same time (see FIG. 3). Therefore, each one-dimensional image data obtained by capturing an image with the CCD camera 11 is similarly binarized for each pixel of the CCD camera 11 and integrated in a synchronized manner, and is continuously stored in the sheet portion of the blister sheet 43. By comparing each total number of pixels of one value (dark portion) connected to the reference number with the reference number, the appearance of the sheet portion of the blister sheet 43 can be simultaneously inspected in the blister sheet packaging machine 30.

However, in the one-dimensional image data picked up by the CCD camera 11, since the luminance gradation of the surface 2 of the stamp tablet 1 and the sheet portion of the blister sheet 43 are considerably different, the ones used in S3 and S4 described above are used. The one-dimensional image data is obtained by using a comparator (having a specific threshold value different from that of the comparator 14), an image memory, and a shading correction table exclusively for visual inspection of the sheet portion of the blister sheet 43. Each pixel of the CCD camera 11 is binarized and integrated in synchronization.
Thereby, the reliability of the appearance inspection of the sheet portion of the blister sheet 43 can be improved.

[0068]

The method for inspecting the appearance of a tablet and the apparatus for inspecting the appearance of a tablet according to the present invention perform the inspection process without discriminating the stamp on the tablet surface from foreign substances and the like. The efficiency of the inspection process can be greatly improved without being affected by the direction. Therefore, according to the method for inspecting the appearance of a stamped tablet of the present invention, the appearance of the stamped tablet filled in the pocket of the blister sheet being conveyed can be inspected in the blister sheet packaging machine.

In addition, since the inspection process is performed by grasping the stamp on the surface of the tablet with a pixel of one value equal to that of a foreign substance or the like, the object of the appearance inspection is not limited to the stamp tablet. Therefore, any tablet that can be normally imaged can be subjected to the appearance inspection.

Also, by removing the connection area having a size less than a certain value from the object of the visual inspection to remove error factors such as noise from the visual inspection of the imprint tablet, a reliable visual inspection of the imprint tablet can be performed. It can be carried out.

Further, if the results of the already performed appearance inspection are statistically processed to determine the second reference range and the first reference range which are the basis of the appearance inspection of the stamped tablet, reliable stamping can be performed. A visual inspection of the tablet can be performed.

[Brief description of the drawings]

FIG. 1 is a flowchart showing a procedure of a method for inspecting the appearance of a stamped tablet according to the present invention.

FIG. 2 is a block diagram showing the overall configuration of the method for inspecting the appearance of a stamped tablet according to the present invention.

FIG. 3 is a perspective view showing a part of the blister sheet packaging machine, showing a part for imaging the appearance of a stamp tablet filled in a pocket of a blister sheet being conveyed.

FIG. 4 is a block diagram showing a functional configuration of the method for inspecting the appearance of a stamped tablet according to the present invention.

FIG. 5 is a view showing the appearance of a stamp tablet.

FIG. 6 is a diagram illustrating luminance gradation of one-dimensional image data.

FIG. 7 is a diagram showing the appearance of a stamp tablet and a circumscribed rectangle.

FIG. 8 is a diagram showing a table obtained by probabilistically processing appearance inspection results (population of the total number of pixels of one value) of a stamp tablet.

[Explanation of symbols]

 1 stamped tablet 10 stamped tablet appearance inspection device 30 blister sheet packaging machine 43 blister sheet 44 blister sheet pocket part PS total number of pixels of one value B circumscribed rectangle P noise reference number BL circumscribed rectangle long side BS circumscribed rectangle short Side LMAX Long side reference value LMIN Short side reference value

Claims (12)

[Claims] 1. The method according to claim 1, wherein the image data of the entire surface of the imprinting tablet is binarized for each pixel, and it is determined whether or not the circumscribed shapes of all pixels of one value are within a first reference range. A method for inspecting the appearance of a stamped tablet, comprising inspecting the appearance of the tablet. 2. The image data of the entire surface of the imprinting tablet is binarized for each pixel, and the circumscribed shape for all connected regions having pixels of one value and having a size equal to or greater than a certain value is determined. A method for inspecting the appearance of a stamped tablet, comprising: inspecting the appearance of the stamped tablet by determining whether the stamped tablet is within a first reference range. 3. The method for inspecting the appearance of a stamped tablet according to claim 1 or 2, further comprising: determining whether a total number of one of the values for all pixels is within a second reference range. A method for inspecting the appearance of a stamped tablet, comprising inspecting the appearance of the stamped tablet. 4. The method for inspecting the appearance of a stamped tablet according to claim 1 or 2, wherein the pixels of one of the connected areas, each of which has a size equal to or greater than a certain value, are constituted by pixels of one value. A method for inspecting the appearance of the stamped tablet by also determining whether or not the total number of the stamped tablets is within the second reference range. 5. The method for inspecting the appearance of a stamped tablet according to any one of claims 1 to 4, wherein the first reference range is calculated stochastically. Tablet appearance inspection method. 6. The method for inspecting the appearance of a stamped tablet according to claim 3 or 4, wherein the second reference range is calculated stochastically. . 7. The method for inspecting the appearance of a stamped tablet according to any one of claims 1 to 6, wherein the circumscribed shape is a rectangle. 8. The method for inspecting the appearance of a stamped tablet according to claim 7, wherein the object of the first reference range is a long side and a short side of the rectangle. 9. The method for inspecting the appearance of a stamped tablet according to claim 7, wherein the object of the first reference range is the diagonal line of the rectangle. 10. The method for inspecting the appearance of a stamped tablet according to claim 7, wherein the object of the first reference range is the area of the rectangle. 11. The method for inspecting the appearance of a stamped tablet according to any one of claims 1 to 10, wherein the appearance of the stamped tablet filled in the pocket portion of the blister sheet being conveyed is measured in a blister sheet packaging machine. A method for inspecting the appearance of a stamped tablet characterized by inspecting. 12. A stamped tablet appearance inspection apparatus, wherein the stamped tablet appearance inspection method according to any one of claims 1 to 11 is performed.