JP6270319B2 - X-ray inspection equipment - Google Patents

Description

  The present invention relates to an inspection apparatus for a packaging sheet containing tablets and capsules, and more particularly to an X-ray inspection apparatus that inspects biting of contents into a seal portion of the packaging sheet.

  Many tablets and capsules are packed through PTP (Press Through Pack), but when they become large solids such as denture cleaning agents and capsules, the contents are stacked between aluminum sheets and resin sheets. A packaging sheet in which objects are sandwiched at regular intervals is used. As shown in FIG. 1, such a packaging sheet is formed by a pocket portion P in which the contents M are stored and a seal portion Q to which the periphery is welded.

  In such a packaging sheet S, the content M may be cracked or chipped, or the content may be bitten into the seal portion due to a slight timing shift in the manufacturing process. Therefore, an X-ray inspection apparatus is incorporated in this type of production line, and detection of cracks and chipping of the contents M, biting inspection into the seal portion Q, and the like are performed.

  As the inspection apparatus, for example, those disclosed in Patent Documents 1 and 2 are known. In the apparatus of Patent Document 1, a missing item is inspected by performing mask processing on an X-ray transmission image of the content. However, in this apparatus, since the boundary B between the pocket portion P and the seal portion Q in FIG. 1 is not reflected in the X-ray transmission image of the packaging sheet as shown in FIG. 2, the presence or absence of the contents M can be detected. However, there is a problem that the biting of the contents M into the seal portion Q cannot be detected.

  Therefore, in the apparatus of Patent Document 2, the packaging sheet is irradiated with light, the packaging sheet is imaged with a CCD camera, the obtained image is subjected to edge enhancement processing, and as shown in FIG. A distance L1 (L2) from the front end (rear end) A in the direction to the boundary B between the pocket portion P and the seal portion Q is obtained, and an area slightly larger than the area of the pocket portion P is set as the inspection area W based on the distance L1 (L2). . Next, an X-ray transmission image of the packaging sheet S is obtained by an X-ray inspection apparatus, and a positional deviation between the center of gravity of the contents of the transmission image and the center position of the inspection region W is detected, and the degree of the positional deviation is detected. Accordingly, whether the packaging sheet S is good or bad is determined.

Japanese Patent No. 3860144 JP 2009-42172 A

  However, in the apparatus of Patent Document 2, in addition to the X-ray inspection apparatus, the packaging sheet S is imaged by a CCD camera, and the obtained captured image is subjected to edge emphasis processing, so that the boundary between the pocket portion P and the seal portion Q is obtained. It is very expensive because it is necessary to separately provide a device for obtaining the distance L1 (L2) from the front end (rear end) A in B and setting an area slightly larger than the area of the pocket portion P as the inspection area W based on the distance L1 (L2). There was a problem that it would be a simple device.

  Further, in this apparatus, after irradiating the packaging sheet S with light and capturing the reflected light with a CCD camera, the captured image is subjected to edge processing to obtain the boundary B between the pocket portion P and the seal portion Q. Therefore, there is a problem that it cannot be applied when the boundary B is difficult to capture with reflected light, for example, when the pocket portion P is circular and gently rises.

  In addition, since this apparatus is provided with a conveyance guide for controlling the posture during conveyance of the packaging sheet S, if the width of the packaging sheet S changes, the conveyance guide must be adjusted accordingly. There was also a problem of lack of sex.

  The present invention was developed in view of these problems, and provides a new X-ray inspection apparatus that can be widely applied regardless of whether the pocket portion P is rectangular or circular, and that is cheaper and more versatile than conventional ones. Is an issue.

In order to solve the above-mentioned problem, an X-ray inspection apparatus according to the present invention detects an X-ray irradiation unit that irradiates a packaging sheet having a plurality of packaging areas connected to the X-ray, and X-rays that pass through the packaging sheet. An X-ray detection unit that outputs an X-ray transmission signal and image generation that generates an X-ray transmission image of the packaging sheet and a plurality of contents stored in the packaging sheet based on the detected X-ray transmission signal And the region of the packaging sheet in which the boundary between the pocket portion and the seal portion of the region of the packaging sheet is not reflected from the X-ray transmission image, the region of the packaging sheet is inclined with respect to the X axis. If this is the case, rotate the X-ray transmission image until the inclination disappears, and then divide the area of the packaging sheet where the inclination disappears by a predetermined division ratio to identify individual packaging areas Department and each identified By comparing the position of the center of gravity of the X-ray transmission image of an ideal reference position and the contents of the instrumentation area, and a judging section that judges acceptability of the package sheet.

  FIG. 1 shows an example of a packaging sheet S in which a plurality of packaging areas F1 are connected. Each packaging area F1 includes a pocket portion P in which contents M are stored and a seal portion Q in which the periphery is sealed. And is formed from. FIG. 2 is an example of an X-ray transmission image of the packaging sheet S. The X-ray transmission image IM of the packaging sheet S and the X-ray transmission image m of the contents M are clear, but the pocket portion P of FIG. The boundary part B between the seal part Q and the seal part Q is not shown. This is because the amount of attenuation of X-rays when X-rays pass through the pocket portion P and the seal portion Q is substantially equal.

  Therefore, in the present invention, first, the contour F is extracted from the X-ray transmission image IM of the packaging sheet S to specify the region F of the packaging sheet S. For example, when the region F is inclined with respect to the X axis as shown in FIG. 3, the X-ray transmission image IM of the packaging sheet S is rotated until the inclination angle θ becomes zero. Next, as shown in FIG. 4, the specified area F is divided by a preset value to specify the packaging areas F1 and F1. For example, if the area size ratio of the left and right ends with rounded corners is 2 and the dimension ratio of each packaging area F1 excluding the area ratio is 10, the region F specified by the ratio is divided. Moreover, if the area | region F is a rectangle and each packaging area F1 is equal, the rectangular area | region F will be equally divided | segmented. Furthermore, when each packaging area F1 is arranged in rows and columns in a matrix, the identified area F is divided in the vertical direction and the horizontal direction to identify each packaging area F1.

  When each packaging area F1... F1 is specified in this way, the ideal reference position C1 of each packaging area F1... F1 and the gravity center position C2 of the X-ray transmission image m of the contents M are obtained, and their deviations are calculated. calculate. Here, the ideal reference position C1 is a position determined from the outer shape of each packaging area F1,... F1, and if it is a general packaging sheet, the center position of the pocket portion P is each packaging area F1. Since it coincides with the center position of F1, the center position of each packaging area F1... F1 becomes the ideal reference position C1. In the case of a packaging sheet in which the center position of the pocket portion P is shifted from the center position of each packaging area F1... F1, an ideal reference position C1 for the outer shape of each packaging area F1. Based on the set value, the ideal reference position C1 is determined. For example, if each packaging area F1... F1 is a rectangle, an ideal reference position C1 that is a set distance from the four corners of the rectangle is set in advance.

  Here, the case where the center position of the pocket portion P coincides with the center position of each packaging area F1,... F1, the ideal reference position C1 of each packaging area F1,. The packaging areas F1,... F1 can be obtained from the intersection coordinates (x1, y1) of the diagonal lines. That is, the center position of each packaging area F1... F1 is set as an ideal reference position C1. Further, the gravity center position C2 of the X-ray transmission image m of the contents M can be obtained from the symmetrical center coordinates (x2, y2) of the image m because it is symmetrical.

  If the deviation (Δx, Δy) of the coordinates thus obtained is within a predetermined range, it is normal, and if it exceeds the range, it is assumed that the contents M are bitten in the packaging areas F1 and F1. The whole packaging sheet is considered defective.

  According to the present invention, the region F of the packaging sheet S is obtained from the X-ray transmission image, the region F is divided on the image to identify individual packaging areas F1, and the ideal for the packaging area F1. The quality of the packaging sheet S can be determined by comparing the reference position C1 and the center of gravity C2 on the image of the contents, so that it is not necessary to image the packaging sheet with a CCD camera. Therefore, it is possible to provide an X-ray inspection apparatus that is less expensive than the conventional apparatus.

  Moreover, in this invention, even if the pocket part P is rectangular or circular, since the position shift of the content M can be detected exactly, it can be set as a highly versatile X-ray inspection apparatus. In addition, in the present invention, even if the packaging sheet S is inclined with respect to the conveyance direction, it can be corrected by image processing. Therefore, a guide member for regulating the conveyance direction of the packaging sheet S may be provided, Since it becomes unnecessary to adjust according to the width of a packaging sheet, it can be set as a more versatile apparatus.

Plan view showing an example of a packaging sheet X-ray transmission image of the packaging sheet X-ray transmission image in which the packaging sheet is inclined with respect to the X axis X-ray transmission image of each packaging area divided from the packaging sheet 1 is an external perspective view of an X-ray inspection apparatus according to an embodiment of the present invention. Configuration explanatory diagram of the main part of the X-ray inspection apparatus Configuration block diagram of the X-ray inspection apparatus Explanatory drawing which calculates | requires the test | inspection area | region W in the apparatus of patent document 2

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

  FIG. 5 is an external perspective view of an X-ray inspection apparatus according to an embodiment of the present invention. In FIG. 5, an X-ray inspection apparatus 10 includes an inspection chamber 13 having an inlet 11 and an outlet 12, a transfer conveyor 14 spanned from the inlet 11 to the outlet 12, and X-rays from the inlet 11 and the outlet 12. A shielding curtain 15 that prevents leakage of the X-ray, an X-ray irradiation unit 16 that irradiates X-rays into the inspection chamber 13 from above the transport conveyor 14, and an upper and lower belt of the transport conveyor 14. An X-ray detection unit 17 that detects transmitted X-rays, a housing 18 that stores these, a touch panel 19 provided on the front surface of the housing 18, and four support legs 20 that support the housing 18. I have. The examination room 13 and the housing 18 are configured to prevent X-rays from leaking outside except for the entrance 11 and the exit 12 of the examination room 13.

  FIG. 6 shows an arrangement configuration of main parts in the examination room 13. The conveyor 14 is arranged below the pulley 21 on the inlet 11 side, the pulley 22 on the outlet 12 side, and the X-ray examination part 17. The front and rear pulleys 23 and 24, an endless belt 25 stretched between these pulleys 21 to 24, and a motor (not shown) that rotates the pulley 22 on the outlet 12 side are configured. Further, a plurality of sets of shielding curtains 15 shown in FIG. 5 are attached to the entrance 11 and the exit 12, respectively. However, when a light weight such as a packaging sheet S is used, the entrance side is uphill and the exit side is down instead of the shielding curtain 15. In some cases, inclined conveyors that form slopes are provided in front of and behind the conveyor 14, and the inclined conveyors are covered with a shielding hood.

  The X-ray irradiation unit 16 is composed of an X-ray generator provided in the upper stage of the examination room 13, and X-rays irradiated from an X-ray tube (not shown) are orthogonal to the conveyance direction D of the packaging sheet S by a collimator (not shown). The fan-shaped beam is narrowed down in the direction to be irradiated and irradiated in the width direction of the conveyor 14.

  The X-ray detection unit 17 includes a pixel sensor including a plurality of photodiodes arranged in a straight line between the upper and lower belts 25 of the transport conveyor 14 and a scintillator provided thereon. These pixel sensors are arranged in a direction perpendicular to the conveyance direction D of the packaging sheet S, and when the X-rays transmitted through the packaging sheet S and the belt 25 reach the scintillator, they are converted into light there, and the light is photon It is converted into an electrical signal by a diode and output as an X-ray transmission signal.

  The touch panel 19 is configured by a full-dot display liquid crystal display, and a necessary operation condition and inspection condition can be set by operating a setting screen displayed there. For example, on the initial screen before the start of operation, operation conditions such as the conveyance speed of the transfer conveyor 14 and the X-ray intensity of the irradiation unit 16 can be set. On the reservation screen after the start of operation, for example, an X-ray transmission image is processed. Detection items such as detection sensitivity, inspection of missing parts, inspection of foreign matters, cracks and chipping can be set. Furthermore, as setting items unique to the present invention, the length of the packaging sheet S in the conveyance direction, the number of divisions in the vertical and horizontal directions and the division ratio, and the center position of the divided packaging areas F1, F1 (Ideal reference position) The degree of deviation between C1 and the gravity center position C2 of the content M on the image m can be set as a non-defective product.

  FIG. 7 shows a configuration block diagram of the X-ray inspection apparatus 10. In this figure, the control computer 30 includes a CPU 31, a ROM 32, a RAM 33, an HDD 34, and a drive 35 for reading from and writing to a storage medium inserted from the outside.

  The CPU 31 is connected to the ROM 32, RAM 33, HDD 34, and drive 35 via an address bus and data bus, and reads and executes various programs stored in the ROM 32 and HDD 34. The HDD 34 stores inspection conditions input from the touch panel 19 and inspection results such as foreign object inspection and missing part inspection. Further, by operating the touch panel 19, the set inspection conditions can be changed, and the inspection results can be transferred from the HDD 34 to a storage medium inserted in the drive 35.

  The control computer 30 includes a display control circuit that displays various screens on the touch panel 19, a key input circuit that captures data input from the touch panel 19, and a communication port that enables connection to an external device such as a printer or a network such as a LAN. Etc. (both not shown).

  The control computer 30 is connected to the X-ray irradiation unit 16, the X-ray detection unit 17, the belt conveyor motor 14a, the encoder 14b, the photoelectric sensor 26, and the like. The speed of the belt conveyor motor 14a is finely controlled by inverter control, and the encoder 14b detects the speed and feeds it back to the control computer 30. The photoelectric sensor 26 is a synchronous sensor that detects the timing at which the packaging sheet S passes through the fan-shaped X-ray irradiation area, and is composed of a pair of light projectors and light receivers that are opposed to each other with the conveyor 14 interposed therebetween. Even without this, the passage of the edge portion of the packaging sheet S is detected by monitoring the X-ray transmission signal output from the X-ray detection unit 17.

  The HDD 34 stores an inspection program including an image generation module, a contour extraction module, a rotation module, a division module, a center position calculation module, a determination module, a foreign object inspection module, a missing part inspection module, a cracked chip inspection module, and the like. Yes. Then, the CPU 31 reads out and executes these inspection programs from the HDD 34, thereby realizing functions of an image generation unit 36, a specifying unit 37, and a determination unit 38, which will be described later.

  The image generation unit 36 generates a two-dimensional X-ray transmission image IM as shown in FIGS. 2 and 3 based on the X-ray transmission signal output from the X-ray detection unit 17. Specifically, X-ray transmission signals sequentially output from the X-ray detection unit 17 at a constant cycle are input to the control computer 30 and sequentially stored in an internal buffer memory. Then, when the X-ray transmission signal no longer shows a certain change, it is determined that the packaging sheet S has passed through the X-ray detection unit 17 and corresponds to the length of the packaging sheet S already read from that point. Image data is read from the buffer memory and developed into a two-dimensional X-ray transmission image IM as shown in FIG.

  The identification unit 37 identifies the region F of the packaging sheet S from the X-ray transmission image IM generated by the image generation unit 36, and then divides the region F to obtain individual packaging areas F1 as shown in FIG. ..Specify F1. Specifically, the contour extraction module is executed, the contour of the packaging sheet S is extracted from the two-dimensionally developed X-ray transmission image IM, and the region F of the packaging sheet S is specified. For example, when the region F is inclined with respect to the X axis as shown in FIG. 3, the rotation module is executed to rotate the X-ray transmission image IM until the inclination angle θ becomes zero. . Subsequently, the division module is executed, and as shown in FIG. 4, the division ratio set in advance, for example, the left and right end portions rounded at the four corners are divided by 20 pixels, and the others are divided by 150 pixels. Then, each packaging area F1..F1 is specified.

  The determination unit 38 determines the quality of the packaging sheet S by comparing the center position of each packaging area F1... F1 thus identified with the center of gravity position of the image m of the contents M. Specifically, the center position calculation module is executed for each packaging area F1,... F1, the coordinates (x1, y1) of the center position (ideal reference position) C1 for each packaging area F1, and the contents The coordinates (x2, y2) of the centroid position C2 of the X-ray transmission image m are obtained. Subsequently, the deviation between the X-axis direction and the Y-axis direction is calculated, and if the deviation is within a preset allowable range, it is determined to be normal, and if it is outside the range, it is determined to be abnormal. In this way, each packaging area F1,... F1 is sequentially judged. If all the packaging areas F1,... F1 are normal, the packaging sheet S is normal, and if any abnormality is found, the packaging sheet S is found. Is determined to be defective. In that case, when the abnormal packaging area F1 is found, the inspection for the subsequent packaging area F1 may be omitted, and the packaging sheet S may be determined to be defective.

  Thus, when it is determined that the packaging sheet S is defective, the control computer 30 outputs a sorting signal to a sorting device (not shown) on the downstream side. In response to the signal, the sorting device removes it from the production line at the timing when the corresponding packaging sheet S reaches the sorting position.

In addition, the control computer 30 incorporates a foreign matter inspection module, a missing part inspection module, and a cracked part inspection module. For the packaging sheet S determined to be normal, further foreign matter inspection, missing part inspection, cracking are performed. Chip inspection is performed. Specifically, the X-ray transmission image IM generated by the image generation unit 36 is binarized, and there is an area that appears darker than a preset threshold in the image IM or the X-ray transmission image m of the contents. For example, it is determined that the packaging sheet S contains foreign matter. Further, when there is no image m that should appear at regular intervals in the X-ray transmission image IM, it is determined that the packaging sheet S has a missing content. Furthermore, a crack in the content M is detected by applying a labeling process to the image m. Alternatively, the area of the image m is calculated, and if the area is less than the reference value, it is determined that the content M is missing.
Thus, if an abnormality is found, the packaging sheet S is removed from the production line by the sorting device as described above.

  In this way, if this X-ray inspection apparatus is used, the inspection of biting of the contents M into the seal portion, the inspection of missing parts of the contents M, and the contents can be performed without imaging the appearance of the packaging sheet with a CCD camera. M crack inspection can be performed together.

  As mentioned above, although one Embodiment of this invention was described, this invention is not limited to this, Other forms are employable. For example, in the above embodiment, the circular contents M have been described, but the present invention can be similarly applied even if this is an oval capsule. The center of gravity position in that case can also be obtained by calculating the center of symmetry of the X-ray transmission image m of the contents. Furthermore, the present invention can be similarly applied to not only PTP-packed tablets and capsules but also other continuous packaging sheets, and the contents are not only pharmaceuticals but also denture cleaning agents.

  Moreover, in this embodiment, with respect to the packaging sheet S shown in FIGS. 1 to 4 with rounded four corners, an X-ray transmission image IM including left and right end portions with four corners is set with a preset division ratio. However, instead of dividing, the left and right end portions with four corners are cut from the X-ray transmission image IM to obtain a rectangular area, and the divided areas are equally divided by the set number of divisions, thereby providing each packaging area F1. F1 may be specified.

  Further, in this embodiment, the deviation in the X-axis direction is used to calculate the positional deviation between the center position (ideal reference position) C1 of the packaging area F1 ·· F1 and the center of gravity position C2 of the X-ray transmission image m. The deviation in the Y-axis direction is obtained and it is determined whether or not each deviation is within the allowable range. Instead, the distance between the center position C1 and the center of gravity position C2 is calculated, and the distance is allowed. It may be determined whether it is within the range. In this case, the distance can be calculated by calculating the square root of the sum of the square of the deviation in the X-axis direction and the square of the deviation in the Y-axis direction.

  In the present embodiment, the center position of each packaging area F1... F1 has been described as the ideal reference position C1, but the center position of the pocket portion is shifted from the center position of each packaging area F1. In this case, an ideal reference position C1 for the outer shape of each packaging area F1... F1 may be set in advance, and the ideal reference position C1 may be determined based on the set value. Specifically, a position separated by a set distance (X-axis direction set distance, Y-axis direction set distance) from the four corners of each packaging area F1... F1 specified by the specifying unit 37 may be set as the ideal reference position C1. .

S Packaging sheet M Contents m X-ray transmission image of contents F Packaging sheet area F1 Packaging area IM X-ray transmission image of packaging sheet C1 Ideal reference position of packaging area (center position of packaging area)
C2 Center of gravity position of X-ray transmission image of contents 10 X-ray inspection device 16 X-ray irradiation unit 17 X-ray detection unit 36 Image generation unit 37 Identification unit 38 Discrimination unit

Claims (1)

An X-ray irradiation unit for irradiating a packaging sheet having a plurality of packaging areas with X-rays;
An X-ray detector that detects X-rays transmitted through the packaging sheet and outputs an X-ray transmission signal;
An image generator for generating an X-ray transmission image of the plurality of contents accommodated in the packaging sheet and the wrapping sheet on the basis of the detected X-ray transmission signal,
After identifying the region of the packaging sheet where the boundary between the pocket portion and the seal portion of the region of the packaging sheet is not reflected from the X-ray transmission image, the region of the packaging sheet is inclined with respect to the X axis. In this case, the X-ray transmission image is rotated until the inclination disappears, and then the specific portion that identifies each packaging area by dividing the area of the packaging sheet that is no longer inclined by a preset division ratio;
A determination unit that compares the ideal reference position of each identified packaging area with the center of gravity position of the X-ray transmission image of the contents, and determines the quality of the packaging sheet;
An X-ray inspection apparatus comprising: