JPH0145022B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a capsule inspection device for inspecting surface defects of pharmaceutical capsules.

This type of pharmaceutical capsule consists of a cap and a main body, and the cap and main body are combined to form a capsule. Before filling the capsule with drug, the empty capsule must be inspected for defects on its surface. Capsule defects include:
Defects such as holes, cracks, notches, deformations, etc. that can be determined as an incomplete capsule from the appearance, and bottle holes with a diameter of about 0.1 mm to 2 mm that are difficult to determine as an incomplete capsule from the appearance.
It is well known that there are defects such as thin spots, where the capsule wall thickness is locally thinner than in other areas.

Inspection for this type of defect has conventionally been carried out by visual inspection by an inspector. However, since visual inspection by inspectors has a limited throughput, an alternative inspection is
An inspection device using optical means described in Japanese Patent No. 3709598 is known. The technology shown in this patent is as follows.

That is, FIG. 1 shows a diagram of the principle of the apparatus shown in the above-mentioned patent. In the figure, 1 indicates an inspection head, and the inspection head has capsule driving rollers 2 arranged at regular intervals on its outer circumference. It is rotated intermittently in the clockwise direction indicated by the arrow around the shaft 11. Each capsule drive roller 2 is rotated at high speed in the direction of the arrow via a drive mechanism (not shown). The inspection head 1 has an air suction mechanism that applies suction force to the gap between each roller 2 through a suction chamber. The capsules 3 are aligned by a separately provided capsule supply mechanism and sequentially supplied between the rollers 2 from the position of arrow P. This capsule 3 is sucked and held between the rollers by the air suction mechanism described above. Furthermore, when the roller 2 rotates, the capsule 3 rotates at approximately the same speed as the rotation speed of this roller.

The capsules held and conveyed by the inspection head 1 are inspected for defects during their conveyance. The inspection section that performs defect inspection includes an illumination lamp 4, optical lenses 5 and 6, and an optical sensor 7. The light irradiated from the illumination lamp 4 reaches the surface of the capsule 3 through an optical lens 5 as a single light band elongated in the vertical direction along the axis of the capsule 3. The light reflected through the capsule 3 enters the optical sensor 7 through the optical lens 6. The manner in which the reflected light reflected from the capsule 3 is incident on the optical sensor 7 is schematically shown in FIG. In FIG. 2, a single line of reflected light from the capsule 3 reaches the optical sensor 7 via the optical lens 6. The optical sensor 7 has a plurality of photocells 8 arranged in parallel on its light receiving surface. The light incident on each photocell 8 contains surface information of a different area of the capsule 3. Therefore, by measuring the output of the photocell 8, defects on the surface of the capsule 3 can be inspected.

This inspection device is capable of automatically inspecting the surface of capsules for defects, and is superior to conventional visual inspections performed by inspectors. However, the inspection device requires several dozen photocells 8 when detecting very small defects, specifically, bottle holes. For example, the length of the capsule is 20
mm, and 40 photocells are required to detect a bottle hole with a diameter of 0.5 mm. Although the price of individual photocells is not that expensive, it is not possible to perform highly accurate inspection unless the characteristics of each photocell are the same, so it is necessary to prepare photocells with uniform characteristics, and it is very expensive in terms of maintenance. be disadvantageous to Furthermore, as the number of photocells increases, the number of discrimination circuits must also be increased correspondingly, resulting in an increase in cost.

SUMMARY OF THE INVENTION An object of the present invention is to eliminate the above-mentioned drawbacks of the prior art and to provide a capsule defect inspection device that is capable of accurately inspecting very small defects on the capsule surface, and that has a simple and compact configuration.

According to the present invention, such objects are formed in the shape of an endless strip, rotated in a predetermined rotational direction, and whose longitudinal direction coincides with the rotational direction and arranged in at least one row along the rotational direction. A conveyor belt that has through holes arranged side by side and that individually stores and conveys capsules in each of the through holes, and a conveyor belt that is provided in parallel and has a rotating shaft substantially parallel to the conveying direction of the capsules, and that conveys the capsules. The present invention includes a plurality of rotating rollers that contact the capsules conveyed by the belt and rotate the capsules around their axes, and an optical inspection device that optically inspects the surface of the capsules that rotate in contact with the rotating rollers. This is achieved by a capsule inspection device with the following characteristics.

Next, one embodiment of the present invention will be described in detail based on the drawings.

An overview of an embodiment of the present invention will be explained with reference to FIGS. 3 and 4. FIG.

Capsules are supplied in fixed quantities to the supply port 11 of the apparatus main body 10 by an external capsule supply device, and the capsules are supplied into the supply chamber 12 to the conveyor belt 13. The surfaces of the capsules that are aligned and conveyed individually by the conveyor belt 13 are inspected by an optical inspection device 14, and the output signal of the inspection device 14 is led to a judgment control section 17 to determine whether the products are good or defective. be done. The capsules that have been inspected are sent to a good product discharge chute 16 or a defective product discharge chute 15 depending on whether they are good or defective.
They are classified and discharged. In addition, an operation panel 18 and a setting/display panel 19 housed inside the device are attached to the main body 10 of the device. The operation panel 18 includes pilot lamps that display whether the power is turned on and the operating status, switches that start/stop the device and set the type of capsule to be inspected (transparent, opaque), and count the number of capsules that have been sorted. It consists of counters, etc. The setting/display panel 19 is comprised of switches for setting the operating mode, inspection accuracy, and light intensity level of the inspection device, and pilot lamps for indicating the operating status of each part of the device and the results of capsule discrimination.

Next, the detailed structure of each component of the embodiment shown in FIG. 5 will be explained in detail.

As shown in detail in FIG. 5, the conveyor belt 13 is hung around a pulley 30 and a pulley 31 provided diagonally above the pulley 30, and is rotated in the direction of the arrow by a suitable rotary drive machine. As shown in FIG. 6, the conveyor belt 13 is made of metal and has a through hole 32 on its outer circumferential surface in which the capsules are individually housed in a direction in which the longitudinal direction of the capsules coincides with the traveling direction of the conveyor belt, and a through hole 32 that is made of metal and has a longitudinal direction along the longitudinal direction of the hole 32. The protrusions 33 on both sides are formed at equal intervals in the circumferential direction. The through holes 32 are formed on the conveyor belt 13 in four rows.
Returning to FIG. 5 again to continue the explanation, temporarily hold the capsule and make sure to insert it into the through hole 32 of the conveyor belt 13.
In the supply chamber 12 for supplying capsules, there is a swing plate 3 that appropriately stirs the temporarily reserved capsules to prevent them from overlapping each other and causing clogging.
4, an alignment plate 35 for arranging capsules so that the longitudinal direction of the capsules is in the same direction as the transport direction, and a capsule that is not stored in the through hole 32 of the transport belt 13 or has a bad posture even if it is inserted into the through hole 32. A brush 36 is attached for returning the capsules into the supply chamber 12. The rocking plate 34 is rocked by rocking means, for example, an eccentric roller 341. The capsule 20 accommodated in the through-hole 32 of the conveyor belt 13 is supported by the V-groove 38 of the guide plate 37 on its lower surface, and is conveyed while sliding in the V-groove 38' of the guide plate 37 (see FIG. 7). An easily replaceable plate 39 made of a material with good wear resistance and a low coefficient of friction is attached to the end of the guide plate 37 facing the rotating roller 38. As shown in FIGS. 8 and 9, the rotational axis of the rotating roller 38 substantially coincides with the longitudinal axis of the capsule 20 conveyed by the conveyor belt 13, that is, with the capsule conveyance direction. Rotating roller 3
Two rollers 8 are provided for one row of capsules, and each roller contacts the capsules to rotate the capsules at high speed. The center portion 40 of the outer peripheral surface of the rotating roller 38' is made of rubber, and both ends 41 are made of a material with good wear resistance and a low coefficient of friction. The shaft of the rotating roller 38' is supported by a bearing 42 fixed to a substrate 45, and power from a motor 43 is transmitted by a belt 44. As a result, all the rotating rollers 38 rotate in the same direction. Rotating roller 38
is surrounded by a negative pressure chamber 47 separated by a wall 46 (see FIG. 5). The negative pressure chamber 47 is maintained at a negative pressure by a suitable vacuum through the air suction port 48, and this negative pressure chamber 47 sucks the capsules in contact with the rotating roller 38 to rotate the two capsules. Press it against the roller 38. Thereby, there is no slippage between the capsule and the rotating roller 38, and the rotation of the rotating roller 38 can be reliably transmitted to the capsule. In addition, since the capsule is rotated by negative pressure suction and pressed between the two rotating rollers 38, the capsule has little vibration, and smooth and stable rotation is obtained, so that the capsule rotates in contact with the conveyor belt 13. There is no need to worry about damaging the capsule.

Next, an optical inspection device for inspecting the rotating capsule surface in contact with the rotating roller 38 is shown in FIG.
The optical inspection device 14 is composed of an inspection device 50 that mainly inspects opaque capsules and an inspection device 51 that mainly inspects transparent capsules. The inspection device 50 has an illumination system consisting of an illumination lamp 52 and an optical fiber 53 that guides the light from the lamp to the capsule surface, and a magnifying lens 54 so that the reflected light from the capsule surface is incident on the optical sensor 55. It consists of an optical sensor system. The inspection device 51 has an optical fiber 56 that guides the light from the lamp 52 to the capsule surface.
It consists of an illumination system consisting of a half mirror 57 and an optical sensor system configured so that reflected light from the capsule surface is incident on an optical sensor 59 via a magnifying lens 58. These testers 50 and 51 are arranged corresponding to the rows of through holes 32 of the conveyor belt 13, respectively. The positional relationship between the testers 50, 51 and the capsules in each row is shown in FIGS. 11 and 12. The inspection device 50 is installed slightly shifted by ΔR from the center of rotation of the capsule 20. As a result, the inspection device 5
0 observes diffusely reflected light from the capsule surface. On the other hand, the inspection device 51 is installed in substantially the same plane as the center of rotation of the capsule 20. Thereby, the inspection device 51 observes specularly reflected light from the capsule surface. Since the capsule is being rotated at high speed around its axis by the rotary roller 38 while being conveyed in the longitudinal direction by the conveyor belt 13, the optical sensor 55,
The scanning of the capsule surface by 59 is as shown in FIG. In other words, the capsule surface is scanned in a spiral manner, as shown by the reference numeral 60 indicating scanning lines by the optical sensors 55 and 59. The capsule is thereby scanned over its entire surface. Here, the minimum defect size S (scanning pitch) that can be detected from the capsule surface is determined by: S=V/n・N V: Capsule transport speed n: Number of optical sensors N: Capsule rotation speed . In this example, the number of optical sensors is 1.
The conveyance speed of the capsule 20 is 200 mm/s, the rotation speed of the capsule 20 is 30000 rpm, and the diameter is approximately 0.4 mm.
The above defects can be detected.

The determination control unit 17 that determines and controls whether capsules are good or defective based on the outputs of the optical sensors 55 and 59 will be described later.

Capsule 2 inspected by optical inspection device 14
0 is conveyed to the discharge section. The defective product discharge section includes a nozzle 61 that injects air from the inside to the outside of the conveyor belt 13 and a defective product discharge chute 15 (see FIG. 5). The jet air from the nozzle 61 is arranged to hit the capsule through the hole 62 in the guide plate 37, and the jet air is controlled via a suitable solenoid valve (not shown). A non-defective product discharge chute 16 is provided in the non-defective product discharge section, and is configured to allow the capsules to be discharged by falling naturally.

Next, the progress of transporting the capsule will be explained step by step. When the capsules 20 temporarily held in the supply chamber 12 enter the through holes 32 of the conveyor belt 13 that is being driven in the direction of the arrow in FIG.
The paper slides on the V-groove 38 of the guide plate 37 provided inside the paper and is transported by the transport belt 13. When the capsule is conveyed while sliding on the guide plate 37 and is conveyed from the end of the guide plate 37 onto the rotating roller 38, the capsule is sucked into the negative pressure chamber 47.
It is pressed against a rotating roller 38 that is rotating at high speed. As a result, the capsule is rotated at high speed by the rotary roller 38 while being conveyed by the conveyor belt 13, so that the surface of the capsule is scanned in a spiral manner by the optical inspection device 14. The capsules inspected by the optical inspection device 14 slide on the guide plate 37 from the rotating roller 38 as the conveyance belt 13 progresses and reach the defective product discharge section. If the capsule is defective, it should be placed in defective product ejection chute 1.
When the position 5 is reached, compressed air is injected from the nozzle 61 and discharged into the defective product discharge chute 15. If the capsule is a good product, the capsule is further conveyed by the conveyor belt 13, passes from the guide plate 37 to the pulley 31, is supported by the outer guide plate 63, and reaches the good product discharge section. The capsules that have reached the non-defective product discharge section are discharged into the non-defective product discharge chute 16 by gravity. The capsules released from each chute 15, 16 are collected in a sorting box.

The above-mentioned inclination angle of the conveyor belt 13 is
2, there is a high probability that a capsule will be stored in the through hole 32 of the conveyor belt 13, and the brush 36 removes capsules that are not stored in the through hole 32 of the conveyor belt 13 or capsules that are in a bad posture even if they are in the through hole. It is slanted so that it can be easily returned to the supply chamber. A suitable inclination angle is 40° to 45° from the horizontal plane.

Next, the determination control unit 1 scans the capsule surface in a spiral pattern through optical inspection to determine defects in the capsule.
7 will be explained.

The output waveform diagram of the optical sensors 55 and 59 when there is a small hole with a diameter of about 0.5 mm on the surface of the capsule is shown in the 14th diagram.
and FIG. 15. FIG. 14 shows the output waveform of the optical sensor 55 when the capsule is an opaque capsule and is inspected by the inspection device 50. In the figure 7
0 corresponds to the capsule body, 71 corresponds to the cap portion, and 72 corresponds to the reflected light from the small holes on the capsule surface. FIG. 15 shows the output waveform of the optical sensor 59 when the capsule is a transparent capsule and is inspected by the inspection device 51. In the figure, 73 corresponds to the capsule body, 74 corresponds to the cap portion, and 75 corresponds to the reflected light from the small holes on the capsule surface. As is clear from these figures, it can be seen that even if the capsule is transparent or opaque, changes in reflected light from the small holes on the capsule surface clearly appear.

FIG. 16 shows a block diagram of the determination control section 17. In this FIG. 16, the optical sensor 5
After the photoelectric conversion signals from 5 and 59 are amplified by an amplifier 80, they are guided to the determination control section 17. This determination control section 17 includes a signal processing circuit 81, a determination circuit 8
2, a memory circuit 83, and a drive circuit 84. The signal processing circuit 81 removes the DC component from the output signal from the amplifier 80 to unify the level of the signal for the defective portion, and compares the output signal with a set threshold value according to the inspection accuracy setting of the setting/display panel. and convert it into a binary signal. The determination circuit 82 comprehensively examines the output signal from the signal processing circuit 81, including the type of capsule, defective items, etc., and determines whether it is a good product or a defective product. The quality determination signal from the determination circuit 82 is temporarily stored in the storage circuit 83. The temporarily stored pass/fail judgment signal indicates that the capsule judged to be pass/fail is transferred to the conveyor belt 13.
When it reaches the defective product discharge section, it is read out and transmitted to the drive circuit 84. The drive circuit 84 controls a solenoid valve 85 for discharging a defective product in the case of a defective product according to the pass/fail determination signal. Note that the determination result of the determination circuit 82 is displayed on the setting/display panel 19.

According to this invention, while the capsules are being conveyed in the longitudinal direction by a conveyor belt, two rotating rollers rotate the capsules around their axes for one row of capsules, and the entire surface of the capsules is scanned in a spiral manner. This makes it possible to achieve the following effects:

(1) It is possible to spirally scan the surface of a capsule that rotates stably at high speed, and one or more optical sensors can detect minute defects on the entire surface of the capsule. This greatly simplifies the detection method and detection circuit for signal processing of two-dimensional images by industrial television cameras and the like.

(2) Capsules being conveyed by the conveyor belt are sucked from between two rotating rollers and rotated in contact with the two rotating rollers, so regardless of the size of the capsule, the capsule rotates smoothly, with little vibration and no defects. Detection accuracy can be improved.

(3) When a capsule is rotating in contact with the rotating roller, the only surface in contact with the conveyor belt is the rear end, which is conveyed by the conveyor belt, and this rear end is a spherical surface that makes point contact with the rotating shaft, so that the rotation is affected by the rotation. There is no problem, and since the other surfaces do not come into contact with the conveyor belt, the capsule surface will not be damaged.

(4) Capsules can be transported in a fixed direction, for example, without restricting the direction of the cap,
The structure of the conveyance mechanism is extremely simple and manufacturing costs can be reduced.

(5) Capsule transport speed and rotation speed can be adjusted individually, and resolution (size of defect to be detected) can be changed extremely easily.

(6) Since the capsules are transported by the transport belt, the portion where the capsules are stored in the through holes of the transport belt in the supply section is a straight line, and the probability that the capsules are stored in the through holes of the transport belt can be easily increased.

(7) Since the conveyor belt is arranged at an angle and the capsules are conveyed from a low position to a high position, it is possible to feed capsules that are not stored in the through hole of the conveyor belt or capsules that are in a bad posture even if they are in the through hole in the supply chamber. It can be easily returned indoors.

(8) The structure is extremely simple and maintenance and inspection are easy.

[Brief explanation of drawings]

Fig. 1 is a schematic diagram of a conventional capsule inspection device, Fig. 2 is a detailed diagram of the inspection section in Fig. 1, Fig. 3 is a schematic front view of an embodiment of the present invention, and Fig. 4 is a schematic side view thereof. , FIG. 5 is an enlarged view of essential parts of an embodiment of the present invention, and FIG. 6 shows the conveyor belt in FIG. 5.
6A is a partially enlarged view, FIG. 6B is a sectional view taken along line XX in FIG. 6A, FIG. 6C is a sectional view taken along YY in FIG. 6A, and FIG. -Z sectional view, FIG. 8 is an enlarged view of the rotating roller section in FIG. 5, FIG. 9 is an AA sectional view in FIG. 8, and FIG. 10 is an enlarged view of the optical inspection section in FIG. 5.
Figure 11 is a sectional view taken along line B-B in Figure 10.
2 is a CC sectional view in FIG. 10, FIG. 13 is a scanning line diagram of the tester, FIG. 14 is an output waveform diagram of the tester 50 in FIG. 10, and FIG. 15 is a diagram of the tester in FIG. 51 is an output waveform diagram, and FIG. 16 is a block diagram of the determination control section. 10... Device main body, 11... Supply port, 12...
Supply chamber, 13... Conveyor belt, 14... Optical inspection device, 15... Defective product discharge chute, 16... Good product discharge chute, 17... Judgment control section, 20...
Capsule, 30, 31...Pulley, 32...Through hole, 33...Protrusion, 34...Winging plate, 36...Brush, 38...Rotating roller, 40...Rotating roller center, 41...Rotating Roller end, 43... Drive motor, 44... Belt, 50, 51... Inspection device, 52... Lamp, 53, 56... Optical fiber, 54, 58... Magnifying lens, 55, 59...
Optical sensor, 57...Half mirror.

Claims (1)

[Scope of Claims] 1. Formed in the shape of an endless strip and driven to rotate in a predetermined rotational direction, and having a longitudinal direction coincident with the rotational direction and at least one plate along the rotational direction.
a conveyor belt having a plurality of through holes arranged in rows and forming a conveyance path for storing and conveying capsules individually in each of the through holes; having a rotation axis substantially parallel to the conveyance direction of the capsules; a plurality of rotating rollers that are provided in parallel on a flat portion of the conveyance path and rotate the capsules around their axes in contact with the capsules conveyed by the conveyor belt; The first inspection device mainly inspects the transparent body capsule or the transparent body part of the capsule.
an optical inspection device, wherein the first inspection device and the second inspection device are sequentially arranged in the vicinity of the rotating roller along the conveying direction so as to form a pair; A capsule inspection device comprising; optically inspecting the surface of a capsule rotating in contact with the rotating roller. 2. The capsule inspection device according to claim 1, wherein the conveyor belt has capsule support protrusions at both longitudinal ends of each through hole. 3. In the inspection device according to claim 1 or 2, the conveyor belt is arranged to be inclined so as to convey the capsule from a low position to a high position. Inspection equipment. 4. The inspection device according to claim 3, characterized in that a rocking plate for giving rocking motion to the capsules is provided at a lower position side where the capsules are fed to the conveyor belt. Capsule inspection equipment. 5. In the inspection device according to claim 3 or 4, at a high position of the conveyor belt,
A capsule inspection device characterized by being provided with a brush that returns capsules that are not stored in the through holes of the conveyor belt or capsules that are in a bad posture even if they are inside the through holes into the supply chamber at a lower position of the conveyor belt. . 6. In the inspection device according to any one of claims 1 to 5, the central outer circumferential surface of the rotating roller is formed of an elastic material, and both ends thereof are made of a material with good wear resistance. A capsule inspection device characterized by being made of a material with a low coefficient of friction. 7. In the inspection device according to any one of claims 1 to 6, each rotating roller is rotationally driven by one drive motor via one belt. Capsule inspection equipment. 8. In the inspection device according to claim 1, the first inspection device of the optical inspection means includes an illumination system consisting of an optical fiber system that guides light from an illumination lamp to the capsule surface, and a magnifying lens. and an optical sensor system configured to make reflected light from the capsule surface enter an optical sensor. 9. In the inspection device according to claim 1, the second inspection device of the optical inspection means includes an illumination system consisting of an optical fiber and a half mirror that guide the light from the illumination lamp to the capsule surface, and a magnifying lens. A capsule inspection device comprising: an optical sensor system configured to input reflected light from the capsule surface to an optical sensor via the optical sensor system. 10 In the inspection device according to claim 1 or 8, the first inspection device of the optical inspection means is installed with its center line slightly shifted from the center of rotation of the capsule. Features of capsule inspection equipment. 11. In the inspection device according to claim 1 or 9, the second inspection device of the optical inspection means is installed such that its center line is located in the same plane as the rotation center of the capsule. A capsule inspection device characterized by: