JPH0437938B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a tablet inspection device that inspects the front and back sides of tablets using a video camera method and automatically inspects and selects good products and defective products.

Conventionally, the conventional method for inspecting tablets for good and defective products is to visually inspect the tablets being conveyed on a conveyor and manually remove any defective tablets. A method has also been proposed, but using human visual inspection not only requires a lot of manpower, but also has drawbacks such as defective products being overlooked. In addition, when inspecting with a video camera, a special light is applied to the tablet surface so that the entire surface has uniform brightness, but in the past, the tablet was simply placed on a flat plate, etc. It is difficult to maintain a normal appearance with the top surface of the tablet completely facing upwards, and therefore, the illumination does not hit the top surface uniformly, resulting in incomplete inspection of the tablet.

Previously, a visual inspection device for solid preparations has been proposed in JP-A-54-126719, but this device is a combination of drums with a horizontal rotation axis.
The tablets are transferred between each drum at a position almost horizontal to the center of the rotating drum, and the receiving drum uses suction to absorb the tablets.
In the case of flat tablets and capsules, the inspection posture can be maintained somehow, but with Go stone-shaped tablets, some of the tablets may be sucked diagonally into the hole of the suction drum at the suction point, and the center of the tablet may be in the center of the drum. is not facing correctly,
There is a drawback that the tablets are suctioned and fixed in a tilted position that is not suitable for proper inspection by a television camera.

The present invention has been proposed to solve the above-mentioned conventional drawbacks, and includes an inspection table that is arranged horizontally, rotates, and has tablet storage holes drilled at a predetermined pitch on the same circumference. The upper end is formed into a concave curved surface that matches the curved surface of the tablet, and the lower end is constantly in contact with a ring-shaped cam and moves up and down with the rotation of the inspection table, and at most positions on the circumference, the inspection table is Retracted from the surface,
The length is determined so that the upper surface of the tablet placed on the concave curved surface at the upper end slightly protrudes from the upper surface of the inspection table, so that the tablet whose posture has been corrected can be completely exposed from the hole when inspecting the surface. A plunger is held at a slight distance from the top surface of the inspection table, has a tablet storage hole on its outer circumferential surface that has the same shape as the tablet storage hole of the inspection table, rotates synchronously with it, and communicates with a vacuum source. an inspection drum having an inspection drum, a camera installed on a trajectory along which the tablet storage hole of the inspection table rotates, a camera that converts images of good and defective tablets into electrical signals and sends them to an ejecting section, and a camera that rotates the tablet storage hole of the inspection drum. A camera installed on the normal line of the locus of the test, which converts images of good and bad tablets into electrical signals and sends them to the ejecting unit; a lighting device installed in each camera unit to illuminate the tablets; and a tablet storage hole in the inspection drum. This tablet inspection device consists of an adsorption air hole located near the center of the vacuum source, and a solenoid valve that supplies pressurized air stronger than the vacuum pressure that holds defective tablets at the defective tablet discharge point. A specially designed plunger and a ring-shaped cam are installed in order to correct the correct posture of the tablet by leveling it, and to transfer the correct posture of the tablet from the inspection table where the front surface is inspected to the back inspection drum. This feature is that even if the tablet fed into the hole in the inspection table is initially tilted, as the inspection table rotates, the puncher moves up and down by the ring-shaped cam, correcting the tablet's posture. In addition, the tablets are exposed to specially designed lighting in each inspection section to extract the characteristics of each defect, and then inspected with a video camera.The resulting image is converted into an electrical signal (video signal), We aim to provide a tablet inspection device that extracts features and processes signals in a circuit, then makes a comprehensive judgment using a microcomputer, sends the signals to a sorting section, and uses pressurized air to separate good and defective products. It is something.

Embodiments of the present invention will be described below with reference to the drawings. FIGS. 1 to 8 show embodiments of the present invention, FIG. 1 is a front view, FIG. 2 is a detailed view of the X section in FIG. The figure is a detailed view of the Y section in Figure 1, Figure 4 is a side view, Figure 5 is a Z arrow view in Figure 4, and Figure 6 is a view from D to Figure 4.
D sectional view, Fig. 7 is E-E sectional view of Fig. 6, Fig. 8
Figures A, B, and C are explanatory views showing video, television scanning, and video signals, respectively.

In the figure, reference numeral 1 denotes a disk-shaped inspection table which is horizontally arranged and has a large number of holes 3 at regular intervals on its outer periphery, which are large enough to fit the tablets m, at the top and bottom. It is rotating. Reference numeral 2 denotes a back surface that is orthogonal to the inspection table 1 and whose outer circumferential surface is placed slightly apart from the inspection table 1 surface, and rotates at the same circumferential speed as the inspection table 1 around a horizontally provided axis 2a. The inspection drum is provided with a number of holes 2b on its outer peripheral surface that are located directly above the holes 3 and have the same pitch and diameter as the holes 3. It is connected to the hole.

A plunger 4 is inserted into the hole 3, and its lower end is in contact with the upper surface of the ring-shaped cam 5. It moves up and down according to the shape of the cam 5 as the inspection table 1 rotates, and is constantly pressed against the surface of the cam 5 by a spring 6. The bottom edge is pressed. The upper end of the plunger 4 is recessed from the surface of the inspection table 1 at most positions, and the upper end is formed into a concave curved surface that matches the curved surface of the tablet m placed in the hole 3. The length of the plunger 4 is determined so that the upper surface of the tablet m placed on the upper end slightly protrudes from the upper surface of the inspection table 1. The plunger 4 moves up and down according to the shape of the cam 5, and corrects the inclination of the tablets m in the hole 3 so that all the tablets m are accurately maintained with their upper surfaces facing directly upward.
Therefore, this posture correction must be performed before reaching the video camera 19, so that the plunger 4 is moved up and down by the cam 5 until it reaches the camera 19, and in the lower part of the camera 19, as shown in FIG. In plunger 4, the pill m whose posture has been corrected is hole 3.
It rises to reveal its full form.

Numeral 8 is a tablet hopper, and numeral 9 is a vibrator, which causes the tablets m that have fallen from the hopper 8 into the inclined gutter 8a to fall one by one into the coil chute 10 by vibration. Reference numeral 11 denotes an inverting plate that covers the outer surface of the half circumference of the filling plate 12, and prevents the tablet m put into the pocket 12b from the coil chute 10 from falling down due to the rotation of the filling plate 12. The filling plate 12 is provided with pockets 12b on its outer peripheral surface at the same pitch as the holes 3 of the inspection table 1, and is rotated by a shaft 12a at the same circumferential speed as the inspection table 1. 13 is a motor, and 14 is a speed reducer.

The air transmission plate 15 is in contact with one side of the back inspection drum 2, and has an adsorption air hole 24 and a pressurized air hole 2 provided in the drum 2 and communicating with the hole 2b through a passage 23.
A suction groove 15a communicating with the vacuum cleaner 5 is provided, and a vacuum suction port 15b communicating with a vacuum source (not shown) is provided in the suction groove 15a. 15c is a pressurized air port for removing defective tablets, and communicates with the pressurized air hole 25 of the drum 2 that communicates with the passage 23 and the solenoid valve 18. The solenoid valve 18 is connected to the video cameras 19 and 2.
It opens and closes in response to a detection signal of 0 defective tablets, and is controlled to communicate pressurized air from a pressurizing source to the pressurized air port 15c or to block it.

The video cameras 19 and 20 are conventionally known ones, and images are converted into electrical signals (video signals).
Signal processing with feature extraction is performed using analog and digital electric circuits, and then a comprehensive judgment is made using a microcomputer. When a defective tablet with dirt a, etc. on the front or back side reaches the pressurized air port 15c, a solenoid valve is activated. 18 is opened under control, and defective tablets are removed with pressurized air stronger than the vacuum pressure. 15d is a pressurized air port communicating with a pressure source (not shown) for removing good tablets. Note that the suction groove 15a is wide and normally communicates with the suction air hole 24 and the pressurized air hole 25 at the same time, and only when the pressurized air hole 25 reaches the pressurized air port 15c, it communicates with the air hole 25. are no longer communicating. 26 is the air transmission plate 15
This is a spring that presses the test drum 2 against the inspection drum 2. Further, 16 is a defective lock shooter, and 17 is a good lock shooter.

Reference numerals 21 and 22 indicate illumination devices devised to extract defect characteristics of the tablet m, which are installed at the bottom of the video cameras 19 and 20 in order to accurately detect stains and chips on the tablet m. The light is irradiated so that the surface of m has uniform brightness.

27 and 27a are timing belts, and pulley 2
The rotation of shafts 2a, 12a is transmitted to pulleys 32, 33 via guide rollers 30, 31, respectively.
The inspection drum 2 and the filling plate 12 are rotated at the same circumferential speed as the inspection table 1, respectively. Pulley 2
8 and 29 are from the motor 13 to the reducer 14 and the gear 3
4, 35, 36, and 37, respectively. In FIG. 8, a indicates dirt on the tablet m, b indicates a screen, and c indicates a scanning line.

Next, to explain the operation, the tablet m put into the tablet hopper 8 is passed through the gutter 8a and the coil chute 10 by the vibrator 9 to the pocket 1 of the filling plate 12.
2b. The filling plate 12 rotates at the same peripheral speed as the surface inspection table 1, so that the tablets m enter the holes 3 in the table. According to the rotation of the inspection table 1, the plunger 4 is moved by a cam 5 having a partially uneven surface.
The tablet m moves up and down to correct the inclination of the tablet m in the hole 3, is carried under the video camera 19 for surface inspection, and is lifted up by the plunger 4 as shown in FIG.

The video camera 19 is adjusted to detect dirt, chips, etc. on the surface of the tablet. In addition, in order to accurately detect stains and chips using the video camera 19, it is necessary to use a lighting device 2 that provides uniform brightness on the surface of the tablet m.
1 is required. If the tablet m whose surface is inspected with the video camera 19 has dirt a as shown in Fig. 8A,
By scanning the screen b on the television, it is converted into a video signal as shown in B in c, judged by a microcomputer (not shown), and the signal is sent to a solenoid valve. Next, both good and bad tablets are inspected in the back side inspection drum 2.
It is sucked into the hole 2b of this drum 2 directly below.
Drum 2 has holes 2b used for tablet adsorption and defective tablet ejection.
A passage 23 through which air is communicated is opened, and the passage 23 is connected to the electromagnetic valve 18 and the pressurized air source via the adsorption/exhaust air transmission plate 15 through the pressurized air hole 25. Note that a rubber ring is fitted into the suction hole 2b of the drum 2 in order to accurately suction the tablet m. Tablet m adsorbed on back inspection drum 2
is carried upward by the rotation of the drum, and the back side is inspected by the back side inspection video camera 20 in the same manner as the video camera 19. In this case, lighting fixture 2
In step 2, the back side of the tablet is irradiated.

When the front and back sides of the tablet are inspected by a video camera, a judgment is immediately made as to whether the tablet is good or bad.The judgment is made by sending a signal to the solenoid valve 18 while confirming its position using an electric signal (shift register). When the pressurized air hole 25 of the hole 2b in which the defective tablet was adsorbed in the discharge section reaches the pressurized air port 15c of the air transmission plate 15, the solenoid valve 18 opens and pressurized air is ejected to remove the defective tablet. Blow into lock shooter 16. In addition, good tablets are attracted and moved as they are, and when the suction hole 2b reaches the pressurized air port 15d, they are blown away by the pressurized air and discharged to the good tablet shooter 17 where they are sorted.

That is, among the tablets m adsorbed to the holes 2b provided in the cylindrical surface of the back inspection drum 2 in the discharge section,
In order to reliably send defective tablets to the defective shooter 16, the passage 23 leading to the hole 2b is branched into two at the back, and one suction air hole 24 is used as a vacuum air source, and the other is used as a pressurized air source. The hole 25 is connected to a solenoid valve 18 that opens and closes pressurized air. As a result, the defective tablet is held by the vacuum air while being sent to the defective shooter 16 by pressurized air with a stronger force.
Since the solenoid valve 18 is not opened for defect-free good tablets, they are carried to the good product discharge section while being held by vacuum air.

Here, both of the two small holes reach the pressurized air port 15d, which is connected to pressurized air, so that the tablets are reliably fed into the quality material shooter 17. Further, at the lowest point of the back surface inspection drum 2, that is, from the transfer section from the front surface inspection table 1 to the discharge section, both of the two small holes are connected to a vacuum air source via the suction groove 15a, and the tablet m is placed on the inspection drum 2. It is held by suction in the hole 2b.

As explained in detail above, the present invention is provided with a plunger that moves up and down with the rotation of the inspection table and corrects the inclination by raising and lowering the tablets placed on the upper end. Inspection using a camera to send is compared to the conventional method of inspecting tablets by simply placing them on a board.
Because it is held upward in a very normal position, it is evenly illuminated and fully inspected by a camera. In addition, since the suction drum normally attracts tablets facing up into the suction holes, the back side of the tablet does not tilt with respect to the drum surface, allowing normal inspection with a camera, making it extremely easy to inspect and sort out good and bad tablets. Done accurately and efficiently.

[Brief explanation of drawings]

The drawings show an embodiment of the device of the present invention, and FIG. 1 is a front view, FIG. 2 is a detailed view of the X section in FIG. 1, FIG. 3 is a detailed view of the Y section in FIG. 1, and FIG. 4 is a side view. , FIG. 5 is a Z arrow view in FIG. 4, FIG. 6 is a sectional view from D to D in FIG. 4, FIG. 7 is a sectional view from E to E in FIG. 6, and FIG.
B and C are explanatory diagrams showing an image, a television scan, and a video signal, respectively. Explanation of the main parts of the diagram, m...tablet, 1...inspection table, 2...inspection drum, 2a...shaft, 2b
... Suction hole, 3 ... Hole, 4 ... Plunger, 5
...Cam, 6...Spring, 13...Motor,
15...Air transmission plate, 15a...Adsorption groove, 15b
...Vacuum inlet, 15c...Pressurized air port, 18...
Solenoid valve, 19, 20... Video camera, 21, 2
2...Lighting device, 23...Passway, 24...Adsorption air hole, 25...Pressurized air hole.

Claims (1)

[Claims] 1. An inspection table which is arranged horizontally and rotates and has tablet storage holes drilled at a predetermined pitch on the same circumference, which is inserted into the hole of the table, and whose upper end is formed into a concave curved surface that matches the curved surface of the tablet; The lower end is in constant contact with the ring-shaped cam and moves up and down as the inspection table rotates, and is retracted from the surface of the inspection table at most positions on the circumference. A plunger whose length is determined so that the top surface slightly protrudes from the top surface of the inspection table, and which rises so that the tablet whose posture has been corrected is completely exposed from the hole when inspecting the surface; an inspection drum which is held at a constant interval and has a tablet storage hole on its outer circumference that has the same shape as the tablet storage hole of the inspection table that rotates at a constant speed, rotates synchronously, and communicates with a vacuum source; A camera having a hole provided on the rotating trajectory, converting images of good and bad tablets into electrical signals and sending it to the ejecting section;
A camera that converts images of defective tablets into electrical signals and sends them to the ejecting section; a lighting device installed in each camera section that irradiates the tablets; A tablet inspection device consisting of an adsorption air hole that communicates with the tablet, and a solenoid valve that supplies pressurized air stronger than the vacuum pressure that holds defective tablets at the defective tablet discharge point.