Tablet printing device and tablet printing method

Abstract

To make it possible to improve inspection accuracy that inspects a tablet on which information is printed by code.SOLUTION: A tablet printing device includes: a printing head printing on a tablet; a controller 40 controlling the printing head; and an imaging device imaging the tablet printed by the printing head. The controller 40 controls the printing head so as to print a code generated on the basis of original data and determines whether or not data read from the code included in the image obtained by the imaging device matches the original data.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] An embodiment of the present invention relates to a tablet printing device and a tablet printing method. [Background technology]

[0002] Conventionally, identification information such as letters has been printed on tablets using an inkjet head. By printing the identification information directly on the tablet, the tablet's identification information can be confirmed even after the tablet is removed from a packaging container such as a PTP (Press Through Pack) sheet.

[0003] However, for example, in the case of tablets to be taken, the amount of information that can be printed on the tablet is limited due to the small size of the tablet. In response to this, if the information to be printed is converted into a code, for example, a two-dimensional code such as a QR Code (registered trademark), and the two-dimensional code is printed on the tablet, the amount of information that can be displayed on the tablet can be increased.

[0004] Tablets with such two-dimensional codes printed on them are usually imaged by an imaging device, and the quality of the two-dimensional code printed on the tablet is determined. The quality determination method is, for example, pattern matching. Generally, two-dimensional codes have an error correction function, so the information can be read even if there are some printing defects or dirt.

[0005] However, when inspection using pattern matching is performed, even if there is no problem in reading the information from the two-dimensional code printed on the tablet, the tablet on which the two-dimensional code is printed may be determined to be defective and rejected, resulting in a decrease in yield. Also, even if the tablet on which the two-dimensional code is printed is determined to be non-defective in inspection using pattern matching, it is possible that the two-dimensional code reader will read incorrect information from the two-dimensional code printed on the tablet. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Publication No. 2019-58220 Summary of the Invention [Problem to be solved by the invention]

[0007] The problem to be solved by the present invention is to provide a tablet printing device and a tablet printing method that can improve the inspection accuracy of tablets on which information is printed in code. [Means for solving the problem]

[0008] A tablet printing device according to an embodiment of the present invention includes a print head that prints on tablets, a control device that controls the print head, and an imaging device that images the tablets that have been printed by the print head, and the control device Former Generated based on data , including the cutout symbol Print a 2D code and printing characters based on the character data outside the two-dimensional code. and controlling the print head to The control device further comprises: Included in the image obtained by the imaging device Identifying an area where the two-dimensional code is printed based on the extracted symbol; and Whether the data read from the two-dimensional code matches the original data only Determine To do , before Regarding areas other than the area where the two-dimensional code is printed Whether the characters printed on the tablet match the character data; and Presence or absence of dirt is determined by pattern matching, and do.

[0009] In the tablet printing method according to an embodiment of the present invention, a control device prints a two-dimensional code including a cut-out symbol and generated based on original data. and printing characters based on the character data outside the two-dimensional code. a print head that prints on the tablet so as to print the tablet, and an imaging device that captures an image of the tablet on which printing has been performed by the print head. Identifying an area where the two-dimensional code is printed based on the extracted symbol; and Whether the data read from the two-dimensional code matches the original data only and determining before Regarding areas other than the area where the two-dimensional code is printed Whether the characters printed on the tablet match the character data; andCheck for dirt Determined by pattern matching This includes: [Effects of the Invention]

[0010] According to an embodiment of the present invention, it is possible to improve the inspection accuracy of tablets on which information is printed in code. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is a diagram illustrating an example of a schematic configuration of a tablet printing apparatus according to a first embodiment. [Figure 2] FIG. 1 is a diagram illustrating an example of a schematic configuration of a printing apparatus according to a first embodiment. [Figure 3] FIG. 2 is a diagram illustrating an example of a schematic configuration of a control device according to the first embodiment. [Figure 4] FIG. 2 is a diagram for explaining an example of a two-dimensional code according to the first embodiment. [Figure 5] 5 is a flowchart showing an example of the flow of a printing process according to the first embodiment. [Figure 6] 10A and 10B are diagrams for explaining an example of a two-dimensional code and a character string according to the second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0012] First Embodiment The first embodiment will be described with reference to FIGS.

[0013] (Example of tablet printing device configuration) As shown in FIG. 1, the tablet printing apparatus 1 according to the first embodiment includes a supplying device 10, a first printing device 20, a second printing device 50, a collecting device 30, and a control device 40.

[0014] The supply device 10 has a hopper 11, an alignment feeder 12, and a delivery feeder 13. The supply device 10 is positioned on one end side of the first printing device 20 and is configured to be able to supply tablets T, which are printing objects, to the first printing device 20. The hopper 11 stores a large number of tablets T and sequentially supplies the stored tablets T to the alignment feeder 12. The alignment feeder 12 aligns the supplied tablets T in a line and transports them in a transport direction A1 (clockwise direction) toward the delivery feeder 13. For example, a belt conveying mechanism or a vibrating feeder is used as the alignment feeder 12. The delivery feeder 13 sequentially sucks in and holds each tablet T lined up in a line on the alignment feeder 12 from above the tablets T, transports the held tablets T in a line to the first printing device 20, and delivers them to the first printing device 20. For example, a belt conveying mechanism is used as the delivery feeder 13. The belt conveying mechanism of the delivery feeder 13 rotates in a conveying direction A2 (counterclockwise direction). The supply device 10 is electrically connected to the control device 40, and the drive thereof is controlled by the control device 40.

[0015] The first printing device 20 includes a transport unit 21, a detection unit 22, a first imaging unit 23, an inkjet head 24, a second imaging unit 25, and a drying unit 27. The inkjet head 24 is an example of a print head (printing unit), and the second imaging unit 25 is an example of an imaging device.

[0016] The conveying unit 21 includes a conveying belt 21a, a driving pulley 21b, a plurality of driven pulleys 21c, a motor 21d, a position detector 21e, and a suction chamber 21f. The conveying belt 21a is an endless belt and is stretched over the driving pulley 21b and each driven pulley 21c. The driving pulley 21b and each driven pulley 21c are rotatably mounted on the device main body (not shown), and the driving pulley 21b is connected to the motor 21d. The motor 21d is electrically connected to the control device 40, and its driving is controlled by the control device 40. The position detector 21e is a device such as an encoder and is attached to the motor 21d. The position detector 21e is electrically connected to the control device 40, and transmits a detection signal to the control device 40. The conveying unit 21 causes the conveying belt 21a to run together with the driven pulleys 21c by rotating the driving pulley 21b by the motor 21d, and conveys the tablets T on the conveying belt 21a in a conveying direction A1 (clockwise direction).

[0017] As shown in FIG. 2, a plurality of circular suction holes 21g are formed in the conveyor belt 21a. Each of these suction holes 21g is a through-hole that adsorbs a tablet T and is aligned in a row along the conveying direction A1 to form a single conveying path. Each suction hole 21g is connected to the inside of the suction chamber 21f (see FIG. 1) via a suction path (not shown) formed in the suction chamber 21f, enabling suction force to be obtained by the suction chamber 21f. A pump is connected to the suction chamber 21f via a suction pipe (not shown), and operation of the pump reduces the pressure inside the suction chamber 21f. The suction pipe is connected to approximately the center of the side surface (plane parallel to the conveying direction A1) of the suction chamber 21f. The pump is electrically connected to the control device 40, and its operation is controlled by the control device 40. When the pressure inside the suction chamber 21f is reduced, the tablet T placed on each suction hole 21g of the conveyor belt 21a is sucked by the suction hole 21g and held on the conveyor belt 21a.

[0018] The detection unit 22 is positioned downstream in the conveying direction A1 from the position where the supply device 10 is provided, and is provided above the conveying path where each suction hole 21g is lined up. This detection unit 22 detects the tablet T that has reached the detection position directly below the detection unit 22 (arrival of tablet T), i.e., the position of the tablet T on the conveyor belt 21a in the conveying direction A1, by emitting and receiving laser light. As the detection unit 22, for example, a displacement sensor is used. Also, various laser sensors such as a reflective laser sensor are used as the displacement sensor. The detection unit 22 is electrically connected to the control device 40, and transmits a detection signal to the control device 40.

[0019] The first imaging unit 23 is positioned downstream in the conveying direction A1 from the position where the detection unit 22 is provided, and is provided above the conveying path in which each suction hole 21g is lined up. Based on the position information of the tablet T in the conveying direction A1 detected by the detection unit 22, the first imaging unit 23 performs imaging at the first imaging timing when the tablet T reaches the imaging position directly below the first imaging unit 23, acquires a first image including the upper surface of the tablet T, and transmits the acquired first image to the control device 40. The first image is used to detect the position of the tablet T in the X direction, Y direction, and θ direction (see FIG. 2). As the first imaging unit 23, various cameras having imaging elements such as a CCD (charge-coupled device) or a CMOS (complementary metal-oxide semiconductor) are used. The first imaging unit 23 is electrically connected to the control device 40, and its operation is controlled by the control device 40. Incidentally, illumination for imaging is also provided as necessary.

[0020] Here, the positions of the tablet T in the X and Y directions are, for example, positions in an XY coordinate system relative to the center (reference position) of the imaging area of ​​the first imaging unit 23. Furthermore, the position in the θ direction is, for example, a position indicating the degree of rotation of the tablet T in a horizontal plane along the XY plane of the imaging area of ​​the first imaging unit 23. This position in the θ direction is detected when the tablet T has a directional shape, such as when a score line is provided on the tablet T or when the tablet T is molded into an oval, elliptical, triangular, rectangular, or other shape. Note that the X and Y directions are positions in the horizontal direction.

[0021] The inkjet head 24 is positioned downstream in the transport direction A1 from the position where the first imaging unit 23 is provided, and is provided above the transport path in which the suction holes 21g are aligned. The inkjet head 24 has a plurality of nozzles 24a (e.g., several hundred to several thousand) (see FIG. 2 ) and is provided so that the direction in which the nozzles 24a are aligned (nozzle row) is perpendicular (an example of an intersection) to the transport direction A1 in a horizontal plane. The inkjet head 24 ejects ink individually from each nozzle 24a by operating a drive element for each nozzle 24a. The inkjet head 24 may be any of various inkjet print heads having drive elements such as piezoelectric elements, heat generating elements, or magnetostrictive elements. The inkjet head 24 is electrically connected to a control device 40, and its drive is controlled by the control device 40.

[0022] The second imaging unit 25 is positioned downstream in the conveying direction A1 from the position where the inkjet head 24 is provided, and is provided above the conveying path in which each suction hole 21g is lined up. Based on the position information of the tablet T in the conveying direction A1 detected by the detection unit 22, the second imaging unit 25 performs an image capture at the second imaging timing when the tablet T reaches the imaging position directly below the second imaging unit 25, acquires a second image including the upper surface of the tablet T, and transmits the acquired second image to the control device 40. The second image is used to inspect the print pattern printed on the tablet T. As with the first imaging unit 23 described above, various cameras having imaging elements such as CCD or CMOS are used as the second imaging unit 25. The second imaging unit 25 is electrically connected to the control device 40, and its operation is controlled by the control device 40. Illumination for imaging is also provided as necessary.

[0023] The drying unit 27 is disposed opposite the conveyor belt 21a, and is provided, for example, below the conveyor unit 21. This drying unit 27 dries the ink applied to each tablet T on the conveyor belt 21a. As the drying unit 27, various dryers are used, such as a blower that dries using a gas such as air, a heater that dries using radiant heat, or a blower that dries using warm air or hot air using both a gas and a heater. The drying unit 27 is electrically connected to the control device 40, and its operation is controlled by the control device 40.

[0024] Here, the first printing device 20 and the second printing device 50 are arranged so that the conveying section 21 and the conveying section 51 overlap one another, and the tablets T printed by the upper first printing device 20 are transferred to the lower second printing device 50, where both sides of the tablets T are printed. Normally, to ensure smooth transfer of the tablets T from the first printing device 20 to the second printing device 50, the conveying speed of the first printing device 20 and the conveying speed of the second printing device 50 are always the same.

[0025] The second printing apparatus 50 has the same structure as the first printing apparatus 20. That is, the second printing apparatus 50 includes a conveying unit 51, a detecting unit 52, a first imaging unit 53, an inkjet head 54, a second imaging unit 55, and a drying unit 57. The conveying unit 51 includes a conveying belt 51a, a driving pulley 51b, multiple driven pulleys 51c, a motor 51d, a position detector 51e, and a suction chamber 51f. The conveying unit 51 conveys tablets T on the conveying belt 51a in a conveying direction A2 (counterclockwise direction). The inkjet head 54 is an example of a print head (printing unit), and the second imaging unit 55 is an example of an imaging device. Note that the elements constituting the second printing apparatus 50 are basically the same in structure as the elements constituting the first printing apparatus 20, and therefore, description thereof will be omitted.

[0026] The recovery device 30 is positioned downstream in the conveying direction A2 from the position where the drying section 57 is provided, and is provided below the conveying section 51. This recovery device 30 has a reusable product recovery section 31, a defective product recovery section 32, and a non-defective product recovery section 33. The recovery device 30 recovers reusable tablets T using the reusable product recovery section 31, recovers defective tablets T using the defective product recovery section 32, and recovers non-defective tablets T using the non-defective product recovery section 33. For example, reusable products are reusable tablets and non-printed tablets that are undamaged and free of foreign matter. Furthermore, defective products include non-printed tablets with foreign matter attached and tablets that fail printing (printed tablets) that are undamaged and free of foreign matter attached, and non-defective products are tablets that pass printing (printed tablets) that are undamaged and free of foreign matter attached. The arrangement order of the reusable product recovery section 31, the defective product recovery section 32, and the non-defective product recovery section 33 in the conveying direction A2 is not limited to the order shown in FIG. 1 and may be changed as appropriate. The recovery device 30 is electrically connected to the control device 40, and its operation is controlled by the control device 40.

[0027] The reusable product collection section 31 has a spray nozzle 31a and a collection box 31b. The defective product collection section 32 has a spray nozzle 32a and a collection box 32b. The non-defective product collection section 33 has a spray nozzle 33a and a collection box 33b. These spray nozzles 31a, 32a, and 33a basically have the same structure, and the collection boxes 31b, 32b, and 33b also basically have the same structure. For this reason, only the spray nozzle 31a and the collection box 31b will be described as representative examples.

[0028] The spray nozzle 31a and the collection box 31b are provided at positions facing each other across a conveying path in which the suction holes 51g of the conveyor belt 51a are aligned. The spray nozzle 31a is disposed in the suction chamber 51f and, for example, sprays gas (e.g., air) toward the conveyor belt 51a, causing the tablets T to fall from the conveyor belt 51a. At this time, the gas sprayed from the spray nozzle 31a passes through the suction holes 51g of the conveyor belt 51a and hits the tablets T. The spray nozzle 31a is electrically connected to the control device 40, and its drive is controlled by the control device 40. The collection box 31b is provided directly below the spray nozzle 31a and below the conveyor unit 51. This collection box 31b receives and stores the tablets T that have fallen from the conveyor belt 51a due to the gas sprayed from the spray nozzle 31a.

[0029] Here, the tablets T that have passed through the reusable product recovery section 31 and the defective product recovery section 32 are transported along with the movement of the conveyor belt 51a, and reach a position near the end of the conveyor belt 51a on the side of each driven pulley 51c. At this position, the suction action no longer acts on the tablets T, but gas is sprayed onto the tablets T from above by the spray nozzle 33a, causing the tablets T to fall from the conveyor belt 51a. Therefore, by providing the spray nozzle 33a, it is possible to reliably cause the tablets T to fall from the conveyor belt 51a. The collection box 33b receives and stores the tablets T that have fallen from the conveyor belt 51a due to the gas sprayed from the spray nozzle 33a.

[0030] The control device 40 controls each part of the tablet printing apparatus 1, such as the supply device 10, first printing device 20, second printing device 50, and recovery device 30, based on various information and various programs. The control device 40 also receives detection data (e.g., detection signals) transmitted from the position detector 21e and detection unit 22 of the conveying unit 21, and the position detector 51e and detection unit 52 of the conveying unit 51, and also receives image data transmitted from the first imaging unit 23, second imaging unit 25, first imaging unit 53, and second imaging unit 55. The control device 40 is realized, for example, by an electronic circuit such as an integrated circuit or a computer.

[0031] (Example of control device configuration) Next, an example of the configuration of the control device 40 will be described with reference to FIG.

[0032] 3, the control device 40 includes an image processing unit 41, a storage unit 42, a control unit 43, and a code generation unit 44. An input device 40a and an output device 40b are connected to the control device 40. The input device 40a is realized by, for example, a switch, a touch panel, a keyboard, a mouse, etc. The output device 40b is realized by, for example, a display, a lamp, a meter, etc.

[0033] The image processing unit 41 captures the first image captured by the first imaging unit 23 or the first imaging unit 53 and the second image captured by the second imaging unit 25 or the second imaging unit 55, and processes the images using a known image processing technique. For example, the image processing unit 41 processes the first image obtained from the first imaging unit 23 to acquire the presence or absence of damage or foreign matter adhering to the tablet T, as well as the position of the tablet T in the X direction, Y direction, and θ direction. The image processing unit 41 also processes the second image obtained from the second imaging unit 25 to acquire image information of the printing pattern printed on the tablet T. The image processing unit 41 transmits the acquired information on the presence or absence of damage or foreign matter adhering to the tablet T, the position information of each tablet T in the X direction, Y direction, and θ direction, and the image information of the printing pattern printed on each tablet T to the control unit 43.

[0034] The memory unit 42 stores various programs and various information. This memory unit 42 is realized by, for example, a semiconductor memory element such as a RAM (Random Access Memory) or a flash memory, or a storage device such as a hard disk or an optical disk. The memory unit 42 stores production data (production information), print data related to printing, conveying speed data, etc. Production data refers to data that changes with the production (manufacturing) of the printed tablets T. An example of production data is a lot number. The production data may be generated based on information input by the user using the input device 40a, or may be generated automatically by the control unit 43.

[0035] The control unit 43 is a computer such as a CPU (Central Processing Unit), MCU (Micro Control Unit), or MPU (Micro Processing Unit), and controls each unit. The control unit 43 may be realized by, for example, hardware and / or software. For example, the control unit 43 controls the supply device 10, the first printing device 20, the second printing device 50, the collection device 30, the image processing unit 41, the storage unit 42, the code generation unit 44, and the like, based on various information and programs stored in the storage unit 42. The control unit 43 also receives detection signals transmitted from the position detector 21e and the detection unit 22 of the conveying unit 21, and the position detector 51e and the detection unit 52 of the conveying unit 51.

[0036] The code generation unit 44 generates a two-dimensional code B1 as shown in FIG. 4 based on the original data, which is a lot number (an example of production data). The two-dimensional code B1 includes a plurality of cut-out symbols B1a, B1b, and B1c. In the example of FIG. 4, only the two-dimensional code B1 is printed on the tablet T. The control unit 43 converts the two-dimensional code B1 generated by the code generation unit 44 into a printing pattern (e.g., raster data), and controls the inkjet head 54 based on the printing pattern to print on the tablet T. The tablet T to be printed is, for example, a ingestible size, with a diameter of 5 to 15 mm. The code generation unit 44 may be realized, for example, by hardware and / or software.

[0037] Here, in the first printing device 20, the control unit 43 acquires the position of the tablet T in the conveying direction A1 on the conveyor belt 21a based on the detection information transmitted from the detection unit 22, i.e., the timing at which the tablet T on the conveyor belt 21a is detected, and based on the position information indicating the position of the tablet T in the conveying direction A1, sets the first imaging timing of the first imaging unit 23, the print start timing of the inkjet head 24, and the second imaging timing of the second imaging unit 25, generates timing information indicating these timings, and stores it in the storage unit 42. The print start timing is the timing at which printing starts on the tablet T that has reached the printing position directly below the inkjet head 24. This type of processing is similar in the second printing device 50. The control unit 43 can acquire information such as the movement amount (rotation amount) and speed of the conveyor belt 21a based on the detection information transmitted from the position detector 21e.

[0038] Furthermore, in the first printing device 20, the control unit 43 sets printability information indicating whether or not printing is possible for the tablets T for which the resulting data has been obtained, based on information on the presence or absence of damage or foreign matter on the tablets T transmitted from the image processing unit 41 (this information is information based on the first image). Then, the control unit 43 sets printing conditions as printing condition information for the tablets T for which printing has been set possible. At this time, the control unit 43 sets printing conditions for the tablets T for which the position information has been obtained, based on position information in the X direction, Y direction, and θ direction of the tablets T transmitted from the image processing unit 41 (this information is information based on the first image).

[0039] For example, the control unit 43 converts the two-dimensional code B1 generated by the code generation unit 44 into a print pattern (e.g., raster data) and sets printing conditions for controlling the inkjet head 54 based on the print pattern. Specifically, the control unit 43 determines the range of nozzles 24a to be used to print the target tablet T in the inkjet head 24, i.e., the nozzle range to be used, based on the position information of the tablet T in the Y direction and the print pattern, and sets printing conditions including the nozzle range to be used and the print start timing. Note that if the tablet T has a directional shape, the control unit 43 sets printing conditions corresponding to the position of the tablet T in the θ direction based on the position information of the tablet T in the θ direction. As an example, the control unit 43 registers 180 print patterns in the memory unit 42, in which the orientation of the print pattern is rotated by 1 degree in a range from 0 degrees to 179 degrees, and selects a print pattern with an angle that matches the position of the tablet T in the θ direction from these print patterns to set the printing conditions. This process is similar to that of the second printing device 50.

[0040] Furthermore, the control unit 43 determines whether the print pattern (e.g., two-dimensional code B1) has been printed in a data-readable manner based on the image information of the print pattern printed on the tablet T transmitted from the image processing unit 41 in the first printing device 20 (this information is based on the second image), and sets print quality information for the tablet T (print status inspection). The image of the print pattern is a second image captured by the second imaging unit 25 (a print inspection camera arranged downstream of the inkjet head 54). The print quality is determined based on this second image. This process is similar in the second printing device 50.

[0041] Specifically, the control unit 43 determines whether the two-dimensional code B1 printed on the tablet T in the second image can be read, and whether the read data (information) matches the original data, which is the lot number. If the control unit 43 can read the two-dimensional code B1 printed on the tablet T and the read data matches the lot number, it determines that there is no problem with the print result of the two-dimensional code B1. On the other hand, if the two-dimensional code B1 printed on the tablet T cannot be read, or the read data does not match the lot number, it determines that there is a problem with the print result of the two-dimensional code B1.

[0042] Furthermore, the control unit 43 determines the presence or absence of defects such as stains (for example, black spots) in the area other than the area where the two-dimensional code B1 is printed, i.e., the area outside the two-dimensional code B1, by image processing. Note that since the area of ​​the two-dimensional code B1 can be identified based on the multiple cut-out symbols B1a, B1b, and B1c included in the two-dimensional code B1, it is sufficient to inspect the presence or absence of stains, etc. only in the identified area other than the area of ​​the two-dimensional code B1.

[0043] Thereafter, if the control unit 43 determines that there are no problems with the printing result of the two-dimensional code B1 and that there are no defects such as dirt in areas other than the two-dimensional code B1, it determines that the printing result of the tablet T is good (passes). On the other hand, if the control unit 43 determines that there is a problem with the printing result of the two-dimensional code B1 or that there are defects such as dirt in areas other than the two-dimensional code B1, it determines that the printing result of the tablet T is bad (fails). Tablets T that are determined to have a bad printing result are ejected by the defective product collection unit 32 (defective ejection device).

[0044] The control unit 43 stores various information (e.g., position information of the tablet T, timing information, printability information, printing condition information, print quality information, etc.) in the storage unit 42 as appropriate. However, when the target tablet T is collected by the collection device 30, for example, after it falls from the downstream end of the conveying unit 51 in the conveying direction A2 and a predetermined time (e.g., several seconds) has elapsed, the various information is deleted from the storage unit 42. However, if such information is required in a later process, it is also possible to leave the various information for each tablet T without deleting it, or to store it in a storage medium (external storage) outside the device. When storing various information for each tablet T, this information may be stored in association with the manufacturing date and time, lot number, etc., so that if defective tablets T are found after shipment after printing, the cause can be traced back to the original information.

[0045] (Printing process) Next, the printing process performed by the tablet printing apparatus 1 will be described with reference to Fig. 5. This printing process also includes an inspection process. Various information such as data required for printing and inspection is stored in advance in the storage unit 42.

[0046] As shown in Fig. 5, in step S1, when a large number of tablets T to be printed are placed in the hopper 11 of the supply device 10, the tablets T begin to be sequentially supplied from the hopper 11 to the alignment feeder 12, and are aligned in a line by the alignment feeder 12 and moved. The tablets T moving in this line are sequentially supplied by the delivery feeder 13 to the conveyor belt 21a of the first printing device 20. The conveyor belt 21a rotates in the conveying direction A1 by the rotation of the drive pulley 21b and each driven pulley 21c by the motor 21d. The tablets T supplied onto the conveyor belt 21a at random intervals are aligned in a line on the conveyor belt 21a and conveyed at a predetermined conveying speed.

[0047] In step S2, the tablet T on the conveyor belt 21a is detected by the detection unit 22. More specifically, when the tablet T on the conveyor belt 21a reaches a detection position (for example, a laser light irradiation position) directly below the detection unit 22, it is detected by the detection unit 22, and based on the timing at which the tablet T is detected, the position of the tablet T in the conveying direction A1 on the conveyor belt 21a is recognized by the control unit 43. Then, position information indicating the position of the tablet T in the conveying direction A1 is generated by the control unit 43 and stored in the memory unit 42.

[0048] In step S3, the tablet T on the conveyor belt 21a is imaged by the first imaging unit 23. Specifically, the tablet T on the conveyor belt 21a is imaged by the first imaging unit 23 at the first imaging timing when the tablet T on the conveyor belt 21a reaches the imaging position directly below the first imaging unit 23, and the first image obtained by imaging by the first imaging unit 23 is transmitted to the control device 40. This first image is processed by the image processing unit 41 of the control device 40. Specifically, the first image is processed by the image processing unit 41, and based on the first image, information on the presence or absence of damage to the tablet T or adhesion of foreign matter, as well as position information of the tablet T in the X direction, Y direction, and θ direction are generated and stored in the memory unit 42.

[0049] In step S4, the control unit 43 determines whether printing is possible on the target tablet T based on information on the presence or absence of damage to the tablet T or foreign matter attached thereto. If it is determined that printing on the target tablet T is possible (Yes in step S4), the process proceeds to step S5. Note that, based on information such as the position information of the tablet T in the X direction, Y direction, and θ direction, and the printing pattern, printing conditions including the nozzle range to be used and the printing start timing for the tablet T set as printable (printable tablet T) are set in the memory unit 42. Based on the above-mentioned print start timing (the timing at which printing on the tablet T is started), the ejection timing for the tablet T (the timing at which ink is ejected onto the tablet T) is determined. On the other hand, if it is determined that printing on the target tablet T is not possible (No in step S4), the process proceeds to step S9, and operations related to printing and inspection on the target tablet T are restricted. Note that the printability information for the tablet T is appropriately stored in the memory unit 42. Note that "restriction" of operations related to printing and inspection means that at least processing related to printing and inspection on the target tablet T is not performed.

[0050] In step S5, printing is performed by the inkjet head 24 based on the above printing conditions. That is, the control unit 43 controls the inkjet head 24 to print a predetermined print pattern (e.g., two-dimensional code B1) on the printable tablets T on the conveyor belt 21a. In detail, the printable tablets T on the conveyor belt 21a that have passed below the first imaging unit 23 are printed by the inkjet head 24 based on the above printing conditions at the print start timing when they reach the printing position directly below the inkjet head 24. In the inkjet head 24, ink is appropriately ejected from each nozzle 24a, and for example, a two-dimensional code B1 is printed on the printing surface, which is the upper surface of the tablet T.

[0051] In step S6, the printed tablets T on the conveyor belt 21a are imaged by the second imaging unit 25. Specifically, the printed tablets T on the conveyor belt 21a are imaged by the second imaging unit 25 at the second imaging timing when they reach the imaging position directly below the second imaging unit 25, and the second image obtained by imaging by the second imaging unit 25 is transmitted to the control device 40. This second image is processed by the image processing unit 41 of the control device 40. Specifically, the second image is processed by the image processing unit 41, and image information of the printing pattern printed on the tablets T is generated and stored in the memory unit 42. The image information is, for example, information including the brightness value (pixel value) for each pixel.

[0052] In processing the second image, in addition to the image information of the printed pattern, the image processing unit 41 may acquire, as necessary, for example, the printing position, shape, and size of the printed pattern printed on the tablet T. For example, the second image transmitted from the second imaging unit 25 may be processed by the image processing unit 41, and information indicating the printing position, shape, and size of the printed pattern already printed on the tablet T may be generated and stored in the memory unit 42.

[0053] In step S7, the control unit 43 performs a print status inspection (pass / fail of the print result) based on the image information of the print pattern printed on the tablet T. Specifically, it is determined whether the two-dimensional code B1 printed on the tablet T in the second image can be read, and whether the read data (information) matches the original data, the lot number. Furthermore, it is determined whether there are any defects such as stains (for example, black spots) in the area other than the area where the two-dimensional code B1 is printed, i.e., the area outside the two-dimensional code B1.

[0054] If the two-dimensional code B1 printed on the tablet T can be read and the read data matches the lot number, it is determined that there is no problem with the print result of the two-dimensional code B1. On the other hand, if the two-dimensional code B1 printed on the tablet T cannot be read or the read data does not match the lot number, it is determined that there is a problem with the print result of the two-dimensional code B1. If it is determined that there is no problem with the print result of the two-dimensional code B1 and that there are no defects such as dirt in areas other than the two-dimensional code B1, it is determined that the print result of the tablet T is good (pass) (Yes in step S7), and processing proceeds to step S8. On the other hand, if the control unit 43 determines that there is a problem with the print result of the two-dimensional code B1 or that there are defects such as dirt in areas other than the two-dimensional code B1, it is determined that the print result of the tablet T is bad (fail) (No in step S7), and processing proceeds to step S9.

[0055] In step S8, the processes of steps S2 to S7 are repeated in the second printing device 50. The tablets T printed in the first printing device 20 are inverted and transferred to the second printing device 50 below, and the processes of steps S2 to S7 are executed in the second printing device 50. This allows double-sided printing on the tablets T, but the two-dimensional code B1 is printed on at least one side of the tablets T. The conveyor belt 51a rotates in the conveying direction A2 by the rotation of the drive pulley 51b and each driven pulley 51c by the motor 51d. Therefore, the tablets T transferred onto the conveyor belt 51a are lined up in a row on the conveyor belt 51a and conveyed at a predetermined conveying speed.

[0056] In step S9, the tablets T on the conveyor belt 51a of the second printing device 50 are collected by the recovery device 30. Specifically, when a reused tablet T reaches the reused product recovery section 31 as the conveyor belt 51a moves, gas is blown onto the tablet T from above by the injection nozzle 31a, and the tablet T falls from the conveyor belt 51a and is collected in the recovery box 31b. Similarly, when a defective tablet T reaches the defective product recovery section 32 as the conveyor belt 21a moves, gas is blown onto the tablet T from above by the injection nozzle 32a, and the tablet T falls from the conveyor belt 51a and is collected in the recovery box 32b. Furthermore, when a non-defective tablet T reaches a position near the end of the conveyor belt 51a on the side of each driven pulley 51c, the suction action on the tablet T ceases to act, and gas is blown onto the tablet T from above by the injection nozzle 33a, and the tablet T falls from the conveyor belt 51a and is collected in the recovery box 33b. The control regarding the blowing of such gas is executed by the control unit 43 based on various information such as, for example, position information of the tablets T, printability information, and print quality information (print state inspection result information).

[0057] In step S10, the control unit 43 determines whether printing has finished. For example, the number of printed tablets T is counted, and when that number reaches a predetermined production number, it is determined that printing has finished. If it is determined that printing has finished (Yes in step S10), the processing ends. On the other hand, if it is determined that printing has not finished (No in step S10), the processing returns to step S1. Note that, regarding the determination of printing completion, it may be determined that printing has finished in response to a user's input operation on the input device 40a, for example, in response to the user pressing a print completion button.

[0058] According to this printing process, the quality of the printing of the two-dimensional code B1 is determined based on whether the data read from the two-dimensional code B1 matches the original data. This prevents tablets T from being judged as defective and being ejected even if the dirt on the tablet T is so small that the two-dimensional code B1 can be read or there are printing gaps. This improves the accuracy of inspection of tablets T with information printed in code.

[0059] Furthermore, in printing and inspecting the two-dimensional code B1, depending on the location and degree of printing defects, ink, or dirt, it is possible that the read data may differ from the original data even though the product is judged to be non-defective by pattern matching. However, according to the first embodiment, such erroneous judgments can be prevented, and the accuracy of inspection of tablets T on which information is printed in code can be improved.

[0060] In addition, by determining only whether the data read from the two-dimensional code B1 matches the original data and determining whether the two-dimensional code B1 is printed properly on the tablet T, the accuracy of inspection of the tablet T on which information is printed in code can be improved.

[0061] Furthermore, when the information printed on the tablets T is variable, such as production information such as a lot number, it may be difficult to prepare a template for pattern matching. Typically, in pattern matching, a non-defective tablet T with a printed pattern is prepared, and an image of the non-defective tablet T is stored as a template. Then, the position where the image of the tablet T to be inspected best matches the template is searched for. At the best match position, the image of the tablet T is compared with the template, and for each pixel, it is determined whether the difference in shading is greater than or equal to a predetermined threshold, and pixels where the difference is greater than or equal to the threshold are extracted. The print quality is determined based on whether the size of the extracted pixel group is within a predetermined threshold. Note that, in order to achieve the required inspection accuracy, the user may need to adjust the template. Therefore, when the information printed on the tablets T is variable, such as production information, it may be impossible to prepare a template in advance, or template generation may increase the user's burden and reduce production efficiency. On the other hand, according to the first embodiment, a template for the two-dimensional code B1 need not be prepared. Therefore, easier processing can be achieved compared to when determining by pattern matching.

[0062] As described above, according to the first embodiment, the tablet printing device 1 includes a print head (e.g., inkjet head 24, 54) that prints on tablets T, a control device 40 that controls the print head, and an imaging device (e.g., second imaging unit 25, 55) that captures images of tablets T printed by the print head. The control device 40 controls the print head to print a two-dimensional code B1 generated based on original data, and determines whether the data read from the two-dimensional code B1 included in the image (e.g., second image) obtained by the imaging device matches the original data. This prevents tablets T from being judged as defective even if the dirt on the tablets T is so small that the two-dimensional code B1 can be read. This improves the inspection accuracy of tablets T on which information is printed as a code. Furthermore, during printing and inspection of the two-dimensional code B1, it is possible to prevent tablets T from being judged as non-defective even if the read data differs from the original data due to print defects or the location and degree of ink or dirt. This improves the inspection accuracy of tablets T on which information is printed as a code.

[0063] <Second embodiment> The second embodiment will be described with reference to Fig. 6. In the second embodiment, differences from the first embodiment will be described.

[0064] As shown in FIG. 6, the control unit 43 according to the second embodiment combines a two-dimensional code B1 and characters (character images) C1, converts them into a print pattern (e.g., raster data), and controls the inkjet head 54 based on the print pattern to print on the tablets T. Examples of the characters C1 include the name of a drug, the content of an active ingredient, the manufacturer's name, and the manufacturer's logo (designed or decorated characters or character strings), as well as character strings that combine these. Data (character data) for such characters C1 is stored in advance in the storage unit 42, for example. Therefore, the control unit 43 reads the character data from the storage unit 42, and combines the characters C1 based on the character data with the two-dimensional code B1 generated by the code generation unit 44 to convert them into a print pattern.

[0065] In the inspection process, the control unit 43 determines whether the two-dimensional code B1 printed on the tablet T in the second image can be read and whether the read data (information) matches the original data, which is the lot number (read inspection). If the control unit 43 can read the two-dimensional code B1 printed on the tablet T and the read data matches the lot number, it determines that there is no problem with the printing result of the two-dimensional code B1. On the other hand, if the two-dimensional code B1 printed on the tablet T cannot be read or the read data does not match the lot number, it determines that there is a problem with the printing result of the two-dimensional code B1. This inspection by reading data is called a "read inspection."

[0066] In addition, the control unit 43 controls the area other than the area where the two-dimensional code B1 is printed, i.e., the area where the two-dimensional code B1 is printed. B The area outside of 1 is inspected for the quality of the printing of characters C1, etc., and for the presence or absence of dirt, etc. Note that the area of ​​two-dimensional code B1 can be identified based on the multiple extracted symbols B1a, B1b, and B1c contained in two-dimensional code B1, so the identified area of ​​two-dimensional code B1 can be masked and pattern matching can be performed to inspect the quality of the printing of characters C1, etc., and for the presence or absence of dirt, etc. Inspection using pattern matching like this is called "pattern matching inspection."

[0067] In the pattern matching test, the control unit 43, for example, registers a printing pattern of the test character C1, etc. in the memory unit 42, and compares the printing pattern of the test character C1, etc. with the printing pattern of the character C1, etc. on the tablet T after actual printing (the printing pattern of the character C1, etc. printed on the tablet T). If the printing pattern of the test character C1, etc. matches the printing pattern of the character C1, etc. printed on the tablet T, it is determined that the printing of the character C1, etc. is good and that there are no defects such as stains. On the other hand, if the printing pattern of the test character C1, etc. does not match the printing pattern of the character C1, etc. printed on the tablet T, it is determined that the printing of the character C1, etc. is poor or that there is a defect such as staining.

[0068] If the control unit 43 determines that there are no problems with the printing result of the two-dimensional code B1, that the printing of characters C1, etc. is good, and that there are no defects such as stains, it determines that the printing result of the tablet is good (passes). On the other hand, if the control unit 43 determines that there are problems with the printing result of the two-dimensional code B1, that the printing of characters C1, etc. is poor, or that there are defects such as stains in areas other than the two-dimensional code B1, it determines that the printing result of the tablet T is poor (fails). Tablets T that are determined to have poor printing results are ejected by the defective product collection unit 32 (defective ejection device).

[0069] Here, in the case of tablets T that are large enough to be ingested, the printable area is small, so the size of the two-dimensional code B1 is also small, and ink adhesion and printing voids are less noticeable. Therefore, by determining whether the printing is good or bad based on whether the data read from the two-dimensional code B1 matches the original data, it is possible to prevent minor defects from causing excessive rejection of defective products and reducing yield.

[0070] Furthermore, since characters C1 and the like are data that are visually inspected by, for example, doctors, pharmacists, patients, etc., any stains or missing prints are easily noticeable and may be misread. According to the second embodiment, characters C1 and the like are inspected by pattern matching, so visually inspected information can be inspected strictly.

[0071] As described above, according to the second embodiment, it is possible to obtain the same effects as in the first embodiment. Furthermore, by performing a readout inspection on the two-dimensional code B1 printed on the tablet T and performing a pattern matching inspection on the characters C1 printed on the tablet T, it is possible to improve the yield while also improving the accuracy of the inspection of the tablet T on which information is printed in code.

[0072] <Other embodiments> In the above description, printing is performed on tablets T using the tablet printing apparatus 1 (tablet printing method) according to the embodiment, but this can also be rephrased as printing on tablets T using the tablet printing apparatus 1 (tablet printing method) according to the embodiment to manufacture printed tablets T. In other words, the tablet printing apparatus 1 can be rephrased as a tablet manufacturing apparatus, and the tablet printing method can be rephrased as a tablet manufacturing method.

[0073] For example, the control device 40 may be provided with software for generating the two-dimensional code B1, or may use a generation service via the Internet. Also, the control device 40 may store the two-dimensional code B1 in advance.

[0074] The two-dimensional code B1 is generated from a lot number as an example of production information, but is not limited to this. The production information may be, for example, the name of the production factory, the date and time of production, the identification number of the tablet printing device 1, the expiration date of the tablets T, or a selection of multiple pieces of information. The original data from which the two-dimensional code B1 is generated may further include the name of the drug and the name of the manufacturer. The original data may also include a URL (Uniform Resource Locator) that allows access to this information.

[0075] Furthermore, if a change occurs in the original data during the printing process performed by the tablet printing device 1, the code generation unit 44 may regenerate a code and continue printing based on this code. At this time, if the original data is changed, the supply of tablets may be temporarily stopped, and tablets T that have not yet been printed and are on the conveyor belts 21a, 51a at that time may be collected by the reusable product collection unit 31. Furthermore, maintenance of the inkjet heads 24, 54 may be performed when it becomes necessary to regenerate the code.

[0076] In addition, in the above explanation, it was explained that the quality of printing of two-dimensional code B1 is determined based on whether the data read from two-dimensional code B1 matches the original data, but it is also possible to determine whether the position of two-dimensional code B1 is printed within a specified area on tablet T.

[0077] Furthermore, for the two-dimensional code B1, the quality of the print can be determined by whether the data read from the two-dimensional code B1 matches the original data, and a pattern matching test can also be performed. In this case, if both tests are successful, the product can be determined to be of good quality.

[0078] Furthermore, in the above explanation, it has been described that the two-dimensional code B1 is printed on one side of the tablet T, but the two-dimensional code B1 may be printed on both sides of the tablet T. The same printing pattern may also be printed on both sides of the tablet T; for example, the two-dimensional code B1 may be printed on the front side and information such as the character C1 may be printed on the back side. Furthermore, in the case of a scored tablet with a score line formed on one side, the character C1 or the like may be printed on the front side where the score line is formed, and the two-dimensional code B1 may be printed on the back side where the score line is not formed.

[0079] In the above explanation, the two-dimensional code B1 is printed on one side of the tablet T, but it is not limited to the two-dimensional code B1, and a barcode (e.g., CODE39, NW-7) or a three-dimensional code printed in color may be printed. That is, the code may be, for example, the two-dimensional code B1, a barcode, or a three-dimensional code. These codes are generated by the code generation unit 44, for example.

[0080] In addition, in the above explanation, an example was given in which the tablets T were transported in a single row, but this is not limited to this, and the number of rows may be two or more rows, and is not particularly limited, and the number of conveyor belts 21a (51a) may be two or more, and is not particularly limited. Furthermore, the number of inkjet heads 24 (54) may be two or more, and is not particularly limited.

[0081] In the above description, a print head in which the nozzles 24a (54a) are arranged in a single row has been exemplified as the inkjet head 24 (54), but this is not limiting and, for example, a print head in which the nozzles 24a are arranged in multiple rows may also be used. Furthermore, a plurality of inkjet heads 24 (54) may also be arranged in a direction perpendicular to the transport direction A1 in a horizontal plane.

[0082] In addition, in the above explanation, an example was given of the inkjet head 24 (54) being arranged so that the direction in which the nozzles 24a (54a) are arranged is perpendicular to the transport direction A1 in a horizontal plane, but this is not limited to this, and for example, the nozzles 24a (54a) may be arranged so that the direction in which they are arranged is diagonally intersecting the transport direction A1 (A2) in a horizontal plane.

[0083] In the above description, the tablets T are supplied randomly, not at regular intervals, onto the conveyor belt 21a (51a), but this is not limiting and the tablets may be supplied at regular intervals. In the above description, the tablets T are suction-held by the suction holes 21g (51g) formed on the conveyor belt 21a (51a), but this is not limiting and the tablets may be accommodated and held in a pocket or the like and transported, or may be held by their own weight on the conveyor belt 21a (51a) and transported.

[0084] Here, the aforementioned tablets T can include tablets used for medicine, food and beverages, cleaning, industrial purposes, or fragrances. Tablets T include plain tablets (plain tablets), sugar-coated tablets, film-coated tablets, enteric-coated tablets, gelatin-coated tablets, multilayer tablets, and dry-coated tablets, and various capsule tablets such as hard capsules and soft capsules can also be included in tablets T. Tablets T can have various shapes, such as a disk, lens, triangle, or oval. When the tablet T to be printed is for medicine or food and beverage use, edible ink is preferably used. As the edible ink, any of synthetic pigment ink, natural pigment ink, dye ink, and pigment ink may be used.

[0085] Although several embodiments of the present invention have been described above, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be embodied in various other forms, and various omissions, substitutions, modifications, and combinations can be made without departing from the spirit of the invention. These embodiments and their modifications are included within the scope and spirit of the invention, and are also included in the scope of the invention and its equivalents as defined in the claims. [Explanation of symbols]

[0086] 1. Tablet printing equipment 10 Feeding device 11 Hopper 12 Alignment Feeder 13 Delivery Feeder 20 First printing device 21 Conveyor 21a Conveyor belt 21b Drive pulley 21c Driven pulley 21d Motor 21e Position detector 21f Suction Chamber 21g suction hole 22 Detection unit 23 First imaging unit 24 Inkjet head 24a nozzle 25 Second imaging unit 27 Drying section 30 Recovery Device 31 Recyclable Goods Collection Department 31a Injection nozzle 31b Collection Box 32 Defective Product Collection Department 32a Injection nozzle 32b Collection Box 33 Good Product Collection Department 33b Collection Box 33a Injection nozzle 40 Control device 40a Input device 40b Output device 41 Image processing section 42 Storage section 43 Control Unit 44 Code Generation Section 50 Second printing device 51 Conveyor 51a Conveyor belt 51b Drive pulley 51c Driven pulley 51d motor 51e Position detector 51f Suction chamber 52 Detection unit 53 First imaging unit 54 Inkjet head 55 Second imaging unit 57 Drying section A1 Conveying direction A2 Conveying direction B1 2D ​​code B1a Cutout Symbol B1b Cutout symbol B1c Cutout Symbol C1 characters T tablets

Claims

1. a print head for printing on the tablets; a control device for controlling the print head; an imaging device that images the tablet on which printing has been performed by the print head; Equipped with The control device printing a two-dimensional code including a segmented symbol generated based on the original data, and controlling the print head to print characters based on character data outside the two-dimensional code; The control device further comprises: Identifying an area where the two-dimensional code is printed based on the extracted symbol included in the image obtained by the imaging device; determining whether or not data read from the specified two-dimensional code included in the area where the two-dimensional code is printed matches the original data; For an area other than the area where the two-dimensional code is printed, determining whether the characters printed on the tablet match the character data and whether there is any dirt by pattern matching; To execute Tablet printing equipment.

2. The control device has a code generation unit that generates the two-dimensional code. The tablet printing device according to claim 1 .

3. The original data includes production information regarding the tablet. The tablet printing device according to claim 1 .

4. The control device Controlling a print head that prints on the tablet so as to print a two-dimensional code that includes the cut-out symbol and is generated based on the original data, and to print characters based on the character data outside the two-dimensional code; Identifying the area where the two-dimensional code is printed based on the extracted symbol included in an image obtained by an imaging device that images the tablet on which printing has been performed by the print head; determining whether or not data read from the specified two-dimensional code included in the area where the two-dimensional code is printed matches the original data; For an area other than the area where the two-dimensional code is printed, determining whether the characters printed on the tablet match the character data and whether there is any dirt by pattern matching; A tablet printing method comprising:

Images