JP5313999B2 - Tablet inspection device and PTP packaging machine - Google Patents

Description

  The present invention belongs to a technical field including a tablet inspection apparatus used in manufacturing a PTP sheet and a PTP packaging machine equipped with the tablet inspection apparatus.

  Generally, a PTP sheet is made of a resin packaging film in which a pocket portion filled with tablets is formed, and aluminum attached to the packaging film so as to seal the opening side of the pocket portion to the packaging film. And a cover film made of steel.

  In manufacturing the PTP sheet, after the tablet is filled in the pocket portion and before the cover film is attached, an inspection relating to tablet abnormality such as chipping or peeling of the tablet is performed.

  In the inspection, after filling the tablet, for example, light is irradiated from the irradiation means provided on the pocket portion side, and the transmitted light is imaged by a camera provided on the side opposite to the irradiation means. Based on the image data of the transmitted light, it is inspected whether there is any abnormality such as chipping or peeling on the tablet surface (see, for example, Patent Document 1).

JP 2004-198175 A

  Conventionally, in order to avoid luminance change due to the color of the tablet, etc., the transmitted light inspection is generally performed using near infrared light of about 850 nm. However, depending on the type of tablet, an appropriate inspection may not be performed. is there.

  For example, a theophylline sustained-release tablet is formed by coating elementary granules mainly composed of theophylline with a water-insoluble substance and compressing the coated granules together with an excipient so that the medicinal component is released continuously for a certain period of time. ing. Therefore, when imaging the theophylline sustained-release tablet by irradiating the near-infrared light, the difference in light transmittance between theophylline constituting the elementary granule and the surrounding excipient components, etc. Therefore, as shown in the schematic diagram of FIG. 13, the captured tablet image 70 is an image having a large luminance spot with a dark central portion and a bright contour portion of the coated granule 71. As a result, it has been difficult to properly detect chipping or peeling of the tablet surface.

  The present invention has been made in view of the above circumstances, and provides a tablet inspection apparatus and a PTP packaging machine capable of dramatically improving inspection accuracy when inspecting for chipping or the like in the manufacturing process of a PTP sheet. This is one of the main purposes.

  Hereinafter, each means suitable for solving the above-described problem will be described separately. In addition, the effect specific to the means to respond | corresponds as needed is added.

Means 1. In the process of manufacturing a PTP sheet containing a theophylline sustained-release tablet formed by coating elementary granules mainly composed of theophylline with a water-insoluble substance and compressing the coated granules together with an excipient, a strip-shaped package to be conveyed A tablet inspection device used in a stage before the cover film is attached in a sealed state so as to close the pocket portion after the tablet is accommodated in the pocket portion formed in the film,
Irradiating the tablet and packaging film with a blue light source capable of irradiating blue light having a peak wavelength in the range of 430 nm to 490 nm, or near infrared light having a peak wavelength in the range of 940 nm to 980 nm An illumination means comprising a possible near-infrared light source;
The illumination means is provided on the opposite side through the packaging film, and imaging means capable of imaging transmitted light that is irradiated from the light source and transmitted through the tablet;
An image processing device for processing an image signal output from the imaging means,
2. The tablet inspection apparatus according to claim 1, wherein the image processing apparatus is configured to detect at least a surface abnormality of the tablet based on image data obtained from the image signal.

  According to the above means 1, in the process of manufacturing a PTP sheet, the theophylline sustained-release tablet is accommodated in the pocket portion formed in the belt-shaped packaging film to be conveyed, and then the cover film is closed so as to close the pocket portion. The inspection by the tablet inspection device is performed at the stage before the is attached in a sealed state. That is, the blue light (430 nm to 490 nm) or the near infrared light (940 nm to 980 nm) is irradiated from the light source of the illumination means to the tablet and the packaging film, and is opposite to the illumination means through the packaging film. With the imaging means provided on the side, transmitted light that is irradiated from the light source and passes through the tablet is imaged. In the image processing apparatus, the image signal output from the imaging unit is processed, and at least a surface abnormality of the tablet is detected based on the image data obtained from the image signal. Here, examples of the abnormal surface of the tablet include cracks and chipping of the tablet.

  In particular, as a light source for illumination means, a blue light source capable of emitting blue light having a peak wavelength within a range of 430 nm to 490 nm or a near infrared light having a peak wavelength within a range of 940 nm to 980 nm can be irradiated. By using such a near-infrared light source, even when the theophylline sustained-release tablet is imaged, it is possible to obtain a tablet image with a small luminance difference between the central portion and the contour portion of the coated granule. As a result, cracks and chippings on the tablet surface can be properly detected, and the inspection accuracy can be dramatically improved.

  Mean 2. The tablet inspection apparatus according to claim 1, wherein the illuminating means includes direct incident light limiting means for removing or dimming light directly incident on the imaging means through the packaging film.

  According to the above means 2, it is possible to reduce the luminance difference between the central part and the contour part of the coated granule, further enhance the function and effect of the above means 1, and to inspect even a fine chip on the tablet surface. Become. In addition, “the direct incident light limiting unit is configured to be able to totally reflect only light within the angle of view of the lens unit with respect to a linear direction connecting at least the light source and the center of the lens unit of the imaging unit. More preferably, it is composed of an angular transmittance control filter.

  Means 3. The illuminating means comprises both the blue light source and the near red light source, and the irradiating light can be switched between the blue light and the near red light. The tablet inspection apparatus described.

  According to the means 3, the inspection can be executed under the irradiation according to the occasional needs. For example, a red film may be employed as the packaging film. However, if the blue light is irradiated from the blue light source in such a case, the packaging film itself may be shielded from light. Concerned. In such a case, by irradiating near red light from a near red light source, it is possible to realize an accurate inspection on the tablet as in the case of the colorless film.

  Means 4. A PTP packaging machine comprising the tablet inspection device according to any one of means 1 to 3.

  By providing the tablet inspection apparatus in the PTP packaging machine as in the above means 4, there is a merit that defective products can be efficiently excluded in the manufacturing process of the PTP sheet.

It is a schematic diagram which shows schematic structure, such as a PTP packaging machine in one Embodiment. (A) is a perspective view which shows a PTP sheet, (b) is a partial expanded sectional view which shows a PTP sheet. It is a fragmentary sectional view which shows an illuminating device typically. It is explanatory drawing which illustrates typically the function of an angle transmittance control filter among illuminating devices. It is a block diagram which shows the electric constitution of a tablet inspection apparatus. It is a flowchart which shows an "inspection routine." (A) is a plan view schematically showing a tablet in which chipping (chip) occurs, has a secant in the center and is engraved, and (b) is a sectional view taken along line JJ in (a). (C) is a graph showing an image signal (lightness) curve along the line JJ. It is a plane schematic diagram for demonstrating the concept of a tablet window. It is a plane schematic diagram for demonstrating the concept of a tablet-shaped window. It is a schematic diagram which shows the image after binarization. It is explanatory drawing explaining the method of the mask process of a secant part. It is a table | surface which shows the result of the test using various light sources. It is a schematic diagram which shows the tablet image obtained by imaging the theophylline sustained release tablet with the conventional test | inspection apparatus.

  Hereinafter, an embodiment will be described with reference to the drawings. In this embodiment, the PTP packaging machine is inspected for defects in the PTP sheet (in particular, abnormalities such as chipping, capping, sticking, etc. called tablet surface defects) by installing the tablet inspection device in the PTP packaging machine. The

  As shown in FIGS. 2A and 2B, the PTP sheet 1 is attached to the container film 3 as a packaging film having a plurality of pocket portions 2 and the container film 3 so as to close the pocket portions 2. And a sealing film 4 as a covered cover film. The container film 3 is made of, for example, a relatively hard thermoplastic resin material having a predetermined rigidity, such as PP (polypropylene) or PVC (polyvinyl chloride), and has light transparency (here, transparent). Presents). The sealing film 4 is made of aluminum. Each pocket 2 contains one theophylline sustained-release tablet 5.

  Theophylline sustained-release tablet 5 (hereinafter simply referred to as “tablet 5”) is prepared by coating elementary granules mainly composed of theophylline with a water-insoluble substance so as to release a medicinal component continuously for a certain period of time. It is formed by tableting with the dosage form.

  As shown in FIG. 1, the PTP packaging machine 7 automatically packages the tablets 5 on the container film 3. Specifically, a belt-shaped resin film such as PP or PVC is fed to the heating device 12 and the molding device 13 by the film feed roll 9 and the tension rolls 10 and 11, and the pocket portion 2 for filling the tablet 5 is used as the resin film. Mold. And if the container film 3 in which the pocket part 2 was shape | molded by the resin film is sent to the bottom of the filling apparatus 14, the filling apparatus 14 will fill each pocket part 2 with the tablet 5 automatically.

  On the other hand, the sealing film 4 formed in a belt shape is guided toward the film receiving roll 18 via the tension rolls 16 and 17. A heating roll 19 can be pressed against the film receiving roll 18, and a lattice-like line (not shown) formed in a slightly convex shape is provided on the outer peripheral surface of the heating roll 19. The container film 3 and the sealing film 4 are fed between the rolls 18 and 19. The sealing film 4 is attached to the container film 3 by passing both the films 3 and 4 between the rolls 18 and 19 in a heated and pressed state. Thus, a long PTP film 20 in which the tablet 5 is filled in each pocket portion 2 is manufactured.

  Now, on the downstream side of the filling device 14 and the upstream side of the film receiving roll 18 and the heating roll 19, defects in the container film 3 (filled tablet 5) are detected along the transfer path of the container film 3. A tablet inspection device 21 for inspection is provided. The tablet inspection device 21 performs an inspection mainly intended to detect surface abnormalities such as cracks and chipping of the tablet 5 filled in the pocket portion 2.

  After the inspection, after the sealing film 4 is attached to the container film 3, the PTP film 20 is cut into one PTP sheet by a punching device (not shown). When a defective product is determined by the tablet inspection device 21, the PTP sheet that has been determined to be defective is separately discharged by a defective sheet discharge mechanism (not shown).

  Now, the outline of the PTP packaging machine 7 is as described above. In the following, the tablet inspection apparatus 21 will be described more specifically based on FIGS.

  The tablet inspection device 21 includes an illumination device 22 as illumination means, a camera 23 as imaging means, an image processing device 24, a monitor 25, a keyboard 26, and the like.

  First, the lighting device 22 will be described in detail. The illuminating device 22 in this embodiment is provided in the pocket part 2 side of the container film 3 (refer FIG. 1), and surface emission is possible. As shown in FIG. 3, the illuminating device 22 has a diffusion plate 27 extending in parallel with the container film 3 on the side close to the container film 3 (upper side in the figure), and an LED mounting substrate 28 is provided in the inside thereof. Is provided. A large number of blue LEDs 28 a (blue light sources) capable of emitting blue light are arranged on the LED mounting substrate 28. Note that the wavelength of blue light is preferably 430 nm or more and 490 nm, and is set to 470 nm in the present embodiment.

  In addition, it is good also as a structure provided with near-infrared LED (near-infrared light source) which can irradiate near-infrared light which has a peak wavelength within the range of 940 nm or more and 980 nm or less instead of blue LED28a (blue light source). Near-infrared light is a wavelength that can be imaged even with a normal CCD camera or the like, and has a higher transmittance of the tablet 5 or the like than visible light such as blue light, so that a more accurate inspection can be performed. In addition, a colored product may be used as the tablet 5 or the like, or a colored film may be used as the container film 3. Even in such a case, it is easy to ignore the dimming element due to coloring. There is.

  Further, an angle transmittance control filter 29 as a direct incident light limiting unit is attached to the surface of the diffusion plate 27 on the container film 3 side. As shown in FIG. 4, the angular transmittance control filter 29 is configured to be capable of total reflection of light on a straight line L <b> 1 that connects at least the light source (here, the blue LED 28 a) and the lens unit center of the camera 23. With respect to the straight line L1, plus or minus light within an angle of view θ of the lens unit can be totally reflected. In other words, the angular transmittance control filter 29 is configured to transmit only light larger than the angle of view θ of the lens unit. As a result, direct incidence of blue light from the light source (blue LED 28a) on the camera 23 is restricted.

  Further, the camera 23 constituting the imaging means is provided on the opposite side (upper side in FIG. 1) to the illumination device 22 via the container film 3, and among the light irradiated from the illumination device 22, The light transmitted through the container film 3 and the tablet 5 can be imaged. In the present embodiment, as the camera 23, a CCD camera sensitive to at least blue light is employed.

  As described above, in this embodiment, the blue light diffused from the illumination device 22 and obliquely irradiated illuminates the container film 3 and the tablet 5, and the light transmitted therethrough is two-dimensionally imaged by the camera 23. It is configured. The image data captured by the camera 23 is converted into a digital signal inside the camera 23 and then input to the image processing device 24 in the form of a digital signal.

  As shown in FIG. 5, the image processing device 24 includes an image memory 41 corresponding to the camera 23, a masking unit 42, a binarizing unit 43, a determination memory 44, an inspection result and statistical data memory 45, and a camera timing control unit 46. In addition, it includes a CPU, an input / output interface 47, and the like, and can perform image data processing, tablet defect determination (inspection), and the like as described later.

  The two-dimensional image data captured by the camera 23 is converted into a digital signal and then stored in the corresponding image memory 41. Further, at the time of inspection, the image data is subjected to masking processing by the masking means 42 and then stored again in the image memory 41. Similarly, after being binarized by the binarizing means 43, the image data 41 again. Is remembered.

  The CPU and the input / output interface 47 execute various processing programs while using the stored contents of the determination memory 44 and the like, and send control signals to the PTP packaging machine 7 or various signals such as operation signals from the PTP packaging machine 7. Is for sending and receiving. Thereby, for example, the defective sheet discharge mechanism of the PTP packaging machine 7 can be controlled. The CPU and input / output interface 47 also has a function of sending display data to the monitor 25. With this function, binary or grayscale image data, a defect inspection result, and the like can be displayed on the monitor 25. Further, the CPU and input / output interface 47 has a function of inputting data from the keyboard 26.

  The inspection result and statistical data memory 45 stores data such as coordinates relating to image data, inspection result data, statistical data obtained by probabilistically processing the inspection result data, and the like. These inspection result data and statistical data can be appropriately displayed on the monitor 25 based on the control of the CPU and the input / output interface 47. Further, the CPU and the input / output interface 47 can send a control signal to the PTP packaging machine 7 based on these inspection result data and statistical data.

  The camera timing control means 46 controls the timing at which image data captured by the camera 23 is taken into the image memory 41. Such timing is controlled based on a signal from an encoder (not shown) provided in the PTP packaging machine 7, and images (photographs) in sheet units (for example, PTP sheet units to be punched) by the camera 23 every time the container film 3 is fed by a predetermined amount. Is done.

  In the present embodiment, the setting process for each window is executed prior to the inspection. The window includes a tablet window JW and a tablet shape window KW that are set in advance. As shown in FIG. 8, the tablet window JW is a boundary for distinguishing between an area in the pocket part 2 (pocket part area) and an area of the sheet part outside the pocket part 2 (sheet part area). It is. The tablet window JW is set in advance based on the non-defective sample and various data, and is concentric with the circle of the pocket portion 2 (when the pocket portion 2 is circular) and has a diameter once ( For example, the diameter is 1 mm) larger. In the inspection, for example, as shown in FIG. 8B, regarding each inspection image data, the tablet window JW is set, and the abnormality of the tablet is detected in the region in the pocket portion 2 ( The area outside the pocket portion 2 (the area with a mesh pattern in the figure) is masked).

  Moreover, as shown in FIG. 9, the tablet shape window KW is used when inspecting whether the shape of the tablet 5 is appropriate, and is set in advance. The tablet-shaped window KW includes an inner-shaped window KW1 that is slightly smaller than the size of the tablet 5 and an outer-shaped window KW2 that is slightly larger than the size of the tablet 5.

  Next, the procedure of the defect inspection (tablet inspection) will be described according to the flowchart of FIG.

  As shown in the figure, in the “inspection routine”, first, in step S101, a gray image for inspection is acquired. Next, in step S102, shading correction is performed on the acquired image, and in the subsequent step S103, binarization processing is performed based on a predetermined threshold value to obtain tablet binarized images A and B. Here, the binarization process will be described with reference to FIGS. 7 and 10. In FIG. 7, (a) is a plan view schematically showing a tablet 5 in which chipping (chip) T occurs, a dividing line PL is provided at the center, and a “C” -shaped engraving KM is attached. (B) is a sectional view taken along line JJ of (a), and (c) is a graph showing an image signal (lightness) curve along the line JJ. The portion of the tablet 5 that is thin due to chipping or the like is easier to transmit light. For this reason, the thinner the portion, the brighter the image. In the binarization process in the present embodiment, first, a binarized image A (see FIG. 10A) that is equal to or greater than the reference threshold δ0 and equal to or less than the first threshold δ1 (within the range d1) is obtained. In the image A, normal tablet parts excluding the chipping T and the secant line PL are bright. At the same time, a binary image B having a reference threshold value δ0 or more and a second threshold value δ2 or less (within range d2) is obtained. In the image B, in addition to the chipping T and the secant line PL, the normal tablet portion excluding the marking KM portion is bright. The reference threshold value δ0, the first threshold value δ1, and the second threshold value δ2 are set to different values depending on the thickness and density of the tablet at that time.

  Thereafter, in step S104, lump processing is performed. More specifically, the result C of the binarized image A obtained by the lump processing and the result D of the binarized image B obtained by the lump processing are obtained.

  Next, in step S105, using the tablet window JW set in advance, the pocket portion area is specified, and in each pocket portion area, a lump whose area value is greater than or equal to the reference tablet area Lo is extracted (a lump less than Lo). Removed). Thereafter, in step S106, it is determined whether or not the number of chunks for each pocket area is “1”. If a negative determination is made, the process proceeds to step S110 described later.

  On the other hand, if the number of lumps for each pocket area is “1”, it is determined in step S107 whether or not the shape of the tablet 5 is good (appropriate) using the tablet shape window KW. to decide. More specifically, the center of gravity of the tablet 5 is obtained from the mass data of the tablet 5, and the tablet shape windows KW (the inner shape window KW1 and the outer shape window KW2) set in advance are set simultaneously so that the center of gravity is concentric. It arranges and it is judged whether the outline of tablet 5 deviates from between both windows KW1 and KW2. Then, when the outline of the tablet 5 deviates from between the two windows KW1, KW2, it is determined that the shape of the tablet 5 is abnormal, and the process proceeds to step S109. Exit once.

  If the determination in step S107 is affirmative, the process proceeds to step S108, the non-defective product is determined for the tablet 5, and the subsequent processing is temporarily ended.

  If a negative determination is made in step S106, the process proceeds to step S110. In step S110, it is determined whether or not “with secant” is set in the current inspection routine, and whether or not the number of chunks is “2”. And only when the setting of “with dividing line” is made and the number of lumps is “2”, the process proceeds to step S111, and the tablet shape of step S107 is good after performing the dividing line mask process. It is determined whether or not.

  Here, the dividing line mask process will be described with reference to FIG. 11. The center-of-gravity positions M1 and M2 of the two blocks are obtained, and the center point C1 of the line segment α passing through the center-of-gravity positions M1 and M2 is obtained. Then, a line segment (straight line) γ that passes through the center point C1 and is orthogonal to the line segment α is obtained, and a band-like region in which the line segment γ has a width of plus or minus β is regarded as a dividing line PL. Set as mask part. By performing the mask process, in the next step S107, the shape inspection can be performed after the influence of the dividing line portion is excluded.

  On the other hand, if it is determined in step S110 that the setting of “with dividing line” is not made, or if it is determined that the number of lumps is not “2”, the process proceeds to step S109, and the tablet 5 is related. Defect determination is performed, and the subsequent processing is temporarily terminated.

  Next, in order to confirm the operational effects achieved by the present embodiment, violet light (400 nm), blue light (430 nm, 470 nm, 490 nm), green light (550 nm), and red light (700 nm) are used as the light source of the illumination device 22. ), Near-infrared light (850 nm, 940 nm, 950 nm, 980 nm) and various light sources that irradiate infrared light (1000 nm). The result is shown in FIG.

  Here, in the tablet image obtained by taking an image of the tablet 5, “◯” is evaluated for those with small luminance spots in which the dark part (bright part in the outline part) does not appear in the central part of the coated granule, and the coated granule An evaluation of “x” was given to a large luminance spot in which a dark part (bright part in the outline part) appeared in the center part of.

  Judging from the results shown in FIG. 12, a blue light source capable of emitting blue light having a peak wavelength in the range of 430 nm to 490 nm, or near infrared light having a peak wavelength in the range of 940 nm to 980 nm. It can be seen that a near-infrared light source capable of irradiating is suitable for examining theophylline sustained-release tablets.

  As described above in detail, according to the present embodiment, unlike conventional transmission light inspection, blue light (430 nm to 490 nm) or near infrared light (940 nm to 980 nm) is used as irradiation light of the illumination device 22. Thus, even when the theophylline sustained-release tablet 5 is imaged, it is possible to obtain a tablet image with less luminance spots at the center portion and the contour portion of the coated granule. As a result, chipping or the like on the tablet surface can be properly detected, and the inspection accuracy can be dramatically improved.

  Furthermore, in this embodiment, the illuminating device 22 includes an angle transmittance control filter 29, and the light directly incident on the camera 23 through the container film 3 is removed or reduced by the angle transmittance control filter 29. It is done. As a result, it is possible to reduce the luminance difference between the central portion and the contour portion of the coated granule, to further enhance the above-described effects, and to inspect even finer chips on the tablet surface.

  In the embodiment described above, for example, a part of the configuration can be appropriately changed as follows. Of course, other modifications not exemplified below are also possible.

  (A) In the above embodiment, a blue LED 28a (blue light source) capable of irradiating blue light (430 nm to 490 nm) or a near infrared LED (near infrared light source) capable of irradiating near infrared light (940 nm to 980 nm) as a light source. ).

  Not only this but the illuminating device 22 is equipped with both the said blue light source and the said near-red light source, and it is good also as a structure which can switch the irradiated light between the said blue light and the said near-red light. .

  (B) In the above embodiment, the angle transmittance control filter 29 is attached to the diffusion plate 27 of the lighting device 22, but the configuration may be omitted.

  DESCRIPTION OF SYMBOLS 1 ... PTP sheet, 2 ... Pocket part, 3 ... Container film, 4 ... Sealing film, 5 ... Theophylline sustained release tablet, 7 ... PTP packaging machine, 21 ... Tablet inspection device, 22 ... Illumination device, 23 ... Camera, 24 ... an image processing device, 27 ... a diffusion plate, 28a ... a blue LED, 29 ... an angle transmittance control filter.

Claims (4)

In the process of manufacturing a PTP sheet containing a theophylline sustained-release tablet formed by coating elementary granules mainly composed of theophylline with a water-insoluble substance and compressing the coated granules together with an excipient, a strip-shaped package to be conveyed A tablet inspection device used in a stage before the cover film is attached in a sealed state so as to close the pocket portion after the tablet is accommodated in the pocket portion formed in the film,
Irradiating the tablet and packaging film with a blue light source capable of irradiating blue light having a peak wavelength in the range of 430 nm to 490 nm, or near infrared light having a peak wavelength in the range of 940 nm to 980 nm An illumination means comprising a possible near-infrared light source;
The illumination means is provided on the opposite side through the packaging film, and imaging means capable of imaging transmitted light that is irradiated from the light source and transmitted through the tablet;
An image processing device for processing an image signal output from the imaging means,
2. The tablet inspection apparatus according to claim 1, wherein the image processing apparatus is configured to detect at least a surface abnormality of the tablet based on image data obtained from the image signal.   The tablet inspection apparatus according to claim 1, wherein the illumination unit includes a direct incident light limiting unit that removes or attenuates light directly incident on the imaging unit through the packaging film.   3. The illuminating means comprises both the blue light source and the near red light source, and the irradiated light can be switched between the blue light and the near red light. The tablet inspection device according to 1.   A PTP packaging machine comprising the tablet inspection device according to any one of claims 1 to 3.

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