Tablet printing device and tablet printing method

Abstract

To provide a tablet printing device and a tablet printing method which can excellently perform an inspection of a tablet.SOLUTION: A tablet printing device according to an embodiment of the present invention is enclosed with a housing, causes a print head device to discharge ink to a tablet conveyed by a conveyance unit to print identification information, and comprises a three-dimensional image acquisition unit which acquires a three-dimensional image of the tablet. The print head device is provided in a region other than a region between the three-dimensional image acquisition unit and a wall surface at a position closer to the three-dimensional image acquisition unit out of the two wall surfaces opposed to each other in the direction along the conveyance direction of the tablet of the housing.SELECTED DRAWING: Figure 1

Description

[Technical Field]

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

[0002] A printing technique using an inkjet head is known for printing identification information (an example of information) such as letters or marks on tablets. A tablet printing device using this technique transports tablets using a transport device such as a conveyor, and ejects ink from each nozzle of an inkjet head arranged above the transport device toward the tablets passing below the inkjet head, thereby printing the identification information on the tablets.

[0003] In such tablet printing devices, various inspections, such as a visual inspection to check for chips or cracks in the tablets, and a printing inspection after the identification information is printed on the tablets, may be performed within the same device. When performing such various inspections, depending on the positions of the sensors, cameras, etc. used for the inspection, printing and inspection may not be performed well. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2015-204943 Summary of the Invention [Problem to be solved by the invention]

[0005] The problem to be solved by the embodiments of the present invention is to provide a tablet printing device and a tablet printing method that can perform tablet inspection well. [Means for solving the problem]

[0006] A tablet printing apparatus according to an embodiment of the present invention Has a rectangular appearance Surrounded by a cabinet , tabletsIn a tablet printing device that prints identification information by ejecting ink from a print head device onto a tablet, The tablet printing apparatus includes a supply device that supplies the tablets, a first printing device that conveys the tablets supplied from the supply device by a first conveyor belt and performs a printing process on one side of the tablets, and a second printing device that conveys the tablets received from the first printing device by a second conveyor belt and performs a printing process on the other side of the tablets, wherein the housing has a first side wall and a second side wall that face each other in the conveying direction of the tablets by the first conveyor belt, the supply device and the second printing device are arranged side by side vertically on the first side wall side, and the first printing device is arranged on the second side wall side at a position higher than the second printing device, and the first printing device includes a first print head device that prints on the one side of the tablets, and a printing head device that is arranged between the first print head device and the second side wall and prints the tablet. Obtaining a three-dimensional image of the tablet 1st 3D image acquisition unit and and The second printing device has a second print head device that prints on the other side of the tablet, and a second three-dimensional image acquisition unit that is provided between the second print head device and the first side wall and acquires a three-dimensional image of the tablet printed by the second print head device, the first three-dimensional image acquisition unit and the second three-dimensional image acquisition unit have a laser light irradiation unit and a three-dimensional image capturing camera, and has a control device that controls the first print head device, the second print head device, the first three-dimensional image acquisition unit, and the second three-dimensional image acquisition unit, and the control device processes the three-dimensional images acquired by the first three-dimensional image acquisition unit and the second three-dimensional image acquisition unit and performs an appearance inspection of the tablet, and has a first cooling means that is provided on the second side wall and supplies a gas to the first three-dimensional image acquisition unit, and a second cooling means that is provided on the first side wall and supplies a gas to the second three-dimensional image acquisition unit. do. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is an overall schematic view of a tablet printing apparatus according to a first embodiment. [Figure 2] FIG. 1 is a partially enlarged view of a tablet printing apparatus according to a first embodiment. [Figure 3] FIG. 2 is a schematic diagram of a first side image acquisition unit of the tablet printing apparatus according to the first embodiment. [Figure 4] FIG. 2 is a schematic diagram of a first three-dimensional image acquisition unit of the tablet printing apparatus according to the first embodiment. [Figure 5] FIG. 2 is a schematic diagram of a second side image acquisition unit of the tablet printing apparatus according to the first embodiment. [Figure 6] FIG. 10 is a schematic view illustrating an entire tablet printing apparatus according to a second embodiment. DETAILED DESCRIPTION OF THE INVENTION

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

[0013] (Basic configuration) As shown in Figure 1, the tablet printing device 1 of one embodiment includes a supply device 10, a first printing device 20, a second printing device 30, a collection device 40, and a control device (control unit) 50 within a housing B.

[0014] The first printing device 20 and the second printing device 30 have basically the same structure, except that the order in which some devices are provided is different. The components of the tablet printing device 1, namely the supply device 10, the first printing device 20, the second printing device 30, and the recovery device 40, are arranged in this order, and the tablets T are transported in this order while a series of processes of supply, printing, and recovery are performed. The path along which the tablets T are transported is called the transport path P. In other words, the upstream side of the transport path P is the supply device 10 side, and the downstream side is the recovery device 40 side. In this embodiment, two parallel rows of transport paths P are formed.

[0015] The supply device 10 has a hopper 11, an alignment feeder 12, and a delivery feeder 13. The supply device 10 is configured to be able to supply tablets T to be printed to the first printing device 20 and is positioned on one end side of the first printing device 20. The hopper 11 stores a large number of tablets T and sequentially supplies the tablets T to the alignment feeder 12. The alignment feeder 12 aligns the supplied tablets T in two rows and transports them toward the delivery feeder 13. The delivery feeder 13 sequentially sucks in and holds each of the tablets T arranged in two rows on the alignment feeder 12 from the top side of the tablets T, transports the held tablets T in two rows to the first printing device 20, and delivers them to the first printing device 20. The supply device 10 is electrically connected to a control device 50, and its drive is controlled by the control device 50. The alignment feeder 12 and the delivery feeder 13 can be, for example, a belt conveying mechanism. The conveying direction of the delivery feeder 13 is indicated by an arrow A2 in FIG. 1 (counterclockwise direction).

[0016] The first printing device 20 includes a first conveying device (conveying section) 21, a detection device 22, a first imaging device (imaging device for printing) 23, a first side image acquisition section SD1, a print head device 24 (first print head device), a second imaging device (imaging device for inspection) 25, a first three-dimensional image acquisition section 3D1, and a drying device 26.

[0017] The first conveying device 21 includes a conveying belt 21a, a driving pulley 21b, multiple (three in the example of FIG. 1) 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 body, and the driving pulley 21b is connected to the motor 21d. The motor 21d is electrically connected to the control device 50, and its driving is controlled by the control device 50. 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 50 and transmits a detection signal to the control device 50. The control device 50 can obtain information such as the position, speed, and movement amount of the conveying belt 21a based on the detection signal. This first conveying device 21 rotates the conveying belt 21a together with each driven pulley 21c by rotating the driving pulley 21b by the motor 21d, and conveys the tablets T on the conveying belt 21a in the conveying direction A1 (clockwise direction), which is the direction of the arrow A1 in Figure 1.

[0018] As shown in FIG. 2, a plurality of circular suction holes 21g are formed on the surface of the conveyor belt 21a. These suction holes 21g are through-holes that adsorb tablets T onto the surface of the conveyor belt 21a, and are arranged in two parallel rows along the conveying direction A1 to form two conveying paths P. Each suction hole 21g is connected to the inside of the suction chamber 21f via a suction path formed in the suction chamber 21f, and suction force can be obtained by the suction chamber 21f. A suction device such as a pump is connected to the suction chamber 21f via an suction pipe (neither is shown), and the inside of the suction chamber 21f is depressurized by operation of the suction device. The suction pipe is connected approximately to the center of the side surface of the suction chamber 21f (a surface parallel to the conveying direction A1). The suction device is electrically connected to the control device 50, and its operation is controlled by the control device 50.

[0019] The detection device 22 has a plurality of detection units 22a (two in the example of FIG. 2). The detection units 22a are arranged one for each conveying path P downstream in the conveying direction A1 from the position on the conveying belt 21a where the tablets T are supplied by the supply device 10, in a direction intersecting (for example, perpendicular to) the conveying direction A1 in the horizontal plane, and are provided above the conveying belt 21a. The detection units 22a detect the position of the tablets T on the conveying belt 21a (the position of the tablets T in the conveying direction A1) by emitting and receiving laser light, and function as trigger sensors for each device located downstream. Various laser sensors such as reflective laser sensors can be used as the detection units 22a. Each detection unit 22a is electrically connected to the control device 50 and transmits a detection signal to the control device 50.

[0020] The first imaging device 23 has a plurality of imaging units 23a (two in the example of FIG. 2). The imaging units 23a are arranged downstream in the conveying direction A1 from the position where the detection device 22 is provided, one for each conveying path P in a direction intersecting (for example, perpendicular to) the conveying direction A1 in the horizontal plane, and are provided above the conveyor belt 21a. Based on the position information of the tablet T described above, the imaging units 23a capture images of the tablets T when they arrive directly below the imaging units 23a, obtain images including the top surfaces of the tablets T (images for printing), and transmit the obtained images to the control device 50. The imaging units 23a can be various cameras having imaging elements such as CCDs (charge-coupled devices) and CMOSs ​​(complementary metal-oxide semiconductors). Each imaging unit 23a is electrically connected to the control device 50, and its operation is controlled by the control device 50. Incidentally, illumination for imaging may also be provided as necessary.

[0021] As shown in FIGS. 3A and 3B, the first side image acquisition unit SD1 includes a side imaging camera SC1, multiple reflecting mirrors (a first reflecting mirror M1 and a second reflecting mirror M2), and a ring light R. FIG. 3A is a front view of the first side image acquisition unit SD1, and FIG. 3B is a plan cross-sectional view taken along line AA in FIG. 3A. As shown in FIG. 3B, the ring light R is disposed above the conveyor belt 21a and parallel to the conveyor belt 21a. Multiple first reflecting mirrors M1 and second reflecting mirrors M2 are arranged in a circular pattern concentrically with the center of the ring light R. The first reflecting mirror M1 is composed of eight mirrors and is disposed above the ring light R so as to extend perpendicular to the ring light R. The second reflecting mirror M2 is also composed of eight mirrors and is disposed above the first reflecting mirror M1 at an angle relative to the perpendicular to the ring light R. Light from the ring illumination R is reflected by the tablet T, and the light reflected by the tablet T is incident on the first reflecting mirror M1 and then received by the side image capturing camera SC1 via a lens (not shown) that receives light guided by the second reflecting mirror M2 (the optical path is indicated by a two-dot chain line in FIG. 3(A)). The first side image acquiring units SD1 are arranged downstream in the conveying direction A1 from the position where the first imaging device 23 is provided, one for each conveying path P in a direction intersecting (e.g., perpendicular to) the conveying direction A1 in the horizontal plane, and are provided above the conveyor belt 21a. Based on the position information of the tablet T described above, the first side image acquiring unit SD1 captures an image of the side of the tablet T reflected by the first reflecting mirror M1 and the second reflecting mirror M2 with the side image capturing camera SC1 when the tablet T arrives directly below the first side image acquiring unit SD1, acquires an image including the side of the tablet T (side image), and transmits the acquired side image to the control device 50. The amount of light emitted by the ring illumination is greater than the amount of light emitted by the first imaging device 23 described above.

[0022] Returning to FIG. 2, the print head device 24 has multiple inkjet print heads 24a (two in the example of FIG. 2). The print heads 24a are arranged downstream in the conveyance direction A1 from the position where the first imaging device 23 is provided, and are arranged one for each conveyance path P in a direction intersecting (e.g., perpendicular to) the conveyance direction A1 in the horizontal plane, and are provided above the conveyance belt 21a. Each print head 24a has multiple nozzles 24b (eight in the example of FIG. 2, but in reality, approximately several hundred to several thousand nozzles), and ink is ejected individually from each nozzle 24b. The print head 24a is provided so that the alignment direction of the nozzles 24b intersects (e.g., perpendicular to) the conveyance direction A1 in the horizontal plane. Various inkjet print heads having drive elements such as piezoelectric elements, heat generating elements, or magnetostrictive elements can be used as the print heads 24a. Each print head 24a is electrically connected to a control device 50, and its drive is controlled by the control device 50.

[0023] The second imaging device 25 has a plurality of imaging units 25a (two in the example of FIG. 2). The imaging units 25a are arranged downstream in the conveying direction A1 from the position where the print head device 24 is provided, in a direction intersecting (for example, perpendicular to) the conveying direction A1 in the horizontal plane, one for each conveying path P, and are provided above the conveying belt 21a. Based on the position information of the tablet T described above, the imaging units 25a capture images when the tablet T arrives directly below the imaging units 25a, obtain images including the top surfaces of the tablets T (images for inspection), and transmit the obtained images to the control device 50. As with the imaging unit 23a described above, various cameras having imaging elements such as CCD or CMOS can be used as the imaging units 25a. Each imaging unit 25a is electrically connected to the control device 50, and its operation is controlled by the control device 50. Incidentally, illumination for imaging may also be provided as necessary.

[0024] As shown in FIGS. 4A and 4B, the first three-dimensional image acquisition unit 3D1 includes a laser light irradiator L1 that irradiates a band-shaped laser beam, a three-dimensional image capture camera C1 that captures an image of the surface of the tablet T irradiated with the laser beam, and a control device 50 that controls the laser light irradiator and the three-dimensional image capture camera and processes the image captured by the three-dimensional image capture camera. FIG. 4A is a view of the first three-dimensional image acquisition unit 3D1 as seen from the upstream side of the conveying direction A1, and FIG. 4B is a view of the first three-dimensional image acquisition unit 3D1 as seen from a direction perpendicular to the conveying direction A1. As shown in FIG. 4A, the laser light irradiator L1 irradiates the conveying belt 21a from directly above the conveying belt 21a so that the irradiation line of the band-shaped laser beam irradiated onto the conveying belt 21a is perpendicular to the conveying direction A1. As shown in FIG. 4B, the three-dimensional image capture camera C1 captures an image of the tablet T from diagonally above downstream of the laser light irradiator L1 in the conveying direction A1. The image captured by the three-dimensional image capturing camera C1 is sent to the control device 50, and is processed by the image processing unit 51 to obtain a three-dimensional image. By analyzing this, the three-dimensional shape of the tablet T is detected (so-called light section method).

[0025] Returning to FIG. 1, the drying device 26 is positioned downstream in the conveying direction A1 from the position where the print head device 24 is provided, and is provided, for example, below the first conveying device 21. This drying device 26 is a drying device common to the two rows of conveying paths P, and dries the ink applied to each tablet T on the conveying belt 21a. As the drying device 26, various drying units can be used, such as a blower that dries using gas such as air, a heater that dries using radiant heat, or a blower that dries using warm or hot air using both gas and a heater. The drying device 26 is electrically connected to the control device 50, and its operation is controlled by the control device 50.

[0026] The tablets T that have passed above the drying device 26 are transported along with the movement of the conveyor belt 21a, and reach a position near the end of the conveyor belt 21a on the side of each driven pulley 21c. At this position, the suction action no longer acts on the tablets T, and the tablets T are released from the state held by the conveyor belt 21a and are transferred from the first printing device 20 to the second printing device 30.

[0027] The second printing apparatus 30 includes a conveying device 31, a detecting device 32, a first imaging device (imaging device for printing) 33, a print head device 34 (second print head device), a second imaging device (imaging device for inspection) 35, a second three-dimensional image acquisition unit 3D2, a second side image acquisition unit SD2, and a drying device 36. The conveying device 31 includes a conveying belt 31a, a driving pulley 31b, multiple (three in the example of FIG. 1) driven pulleys 31c, a motor 31d, a position detector 31e, and a suction chamber 31f. Each element constituting the second printing apparatus 30 has essentially the same structure as the corresponding component of the first printing apparatus 20 described above. Among these, the second side image acquisition unit SD2 and the second three-dimensional image acquisition unit 3D2 are different in their positions and orientations. Therefore, only these elements will be described, and other explanations will be omitted. The transport direction of the second printing device 30 is the transport direction A2 (counterclockwise direction) indicated by the arrow A2 in FIG.

[0028] In the second printing device 30, a second three-dimensional image acquisition unit 3D2 is provided downstream of the second imaging device 35 in the conveying direction A2, and a second side image acquisition unit SD2 is provided at a position facing the drive pulley 31b further downstream. The second three-dimensional image acquisition unit 3D2 has the same structure as the first three-dimensional image acquisition unit 3D1 of the first printing device 20. Unlike the first side image acquisition unit SD1, the second side image acquisition unit SD2 further includes a third reflecting mirror M3. (See Figure 5) .

[0029] The first side image acquisition unit SD1 of the first printing device 20 is provided facing the horizontal portion of the conveyor belt 21a (i.e., the flat portion of the upper surface forming the chamber 21f) and inspects the side of the tablet T sucked and held substantially horizontally, whereas the second side image acquisition unit SD2 of the second printing device 30 is provided facing the curved portion of the conveyor belt 31a (i.e., the curved portion of the drive pulley 31b) and inspects the side of the tablet T sucked and held on the curved portion. As shown in FIG. 5, similar to the first side image acquisition unit SD1 of the first printing device 20, a ring light R is provided so as to face the printing surface of the tablet being conveyed. (not shown) A first reflecting mirror M1 and a second reflecting mirror M2 are arranged, and a reflecting mirror M3 and a camera SC1 are arranged so that the reflected light reflected by the first reflecting mirror M1 and the second reflecting mirror M2 is reflected 90 degrees by a third reflecting mirror M3 and enters the camera via a lens not shown.

[0030] Returning to Fig. 1, the recovery device 40 includes a defective product recovery device 41, a reusable product recovery device 42, and a non-defective product recovery device 43. This recovery device 40 is provided downstream in the conveying direction A2 from the position where the drying device 36 of the second printing device 30 is provided. The recovery device 40 basically recovers defective tablets T using the defective product recovery device 41, recovers reusable tablets T (described later) using the reusable product recovery device 42, and recovers non-defective tablets T using the non-defective product recovery device 43.

[0031] The defective product collecting device 41 has a plurality of spray nozzles 41a and a collection box (collection box) 41b. The spray nozzles 41a are provided for each conveying path P, and the collection box 41b is provided in common to all the conveying paths P.

[0032] The injection nozzles 41a are arranged one for each conveying path P in a direction intersecting (e.g., perpendicular to) the conveying direction A2 in the horizontal plane, and are provided in the suction chamber 31f of the second printing device 30. The injection nozzles 41a, for example, inject gas (e.g., air) toward the conveying belt 31a, causing the tablets T to fall from the conveying belt 31a. At this time, the gas injected from the injection nozzle 41a passes through suction holes (similar to the suction holes 21g shown in FIG. 2) in the conveying belt 31a and hits the tablets T. The injection nozzles 41a are electrically connected to the control device 50, and their driving is controlled by the control device 50.

[0033] The storage boxes 41b are provided directly below the spray nozzles 41a and below the conveying device 31. The storage boxes 41b receive and store tablets T that have fallen from the conveying belt 31a due to the gas sprayed from the spray nozzles 41a.

[0034] The spray nozzle 41a may be installed at a position other than inside the suction chamber 31f of the second printing device 30. For example, the spray nozzle 41a may be installed below the conveying device 31 so that gas is sprayed toward the side of the tablet T conveyed by the conveying belt 31a. In this case, the spray nozzle 41a may be installed at an angle to the vertical direction. In this case, the storage box 41b is installed taking into consideration the gas spray direction of the spray nozzle 41a.

[0035] The reusable item recovery device 42 has a plurality of spray nozzles 42a and a storage box (recovery box) 42b. The plurality of spray nozzles 42a are provided for each conveying path P, and the storage box 42b is provided in common to all the conveying paths P.

[0036] The injection nozzles 42a are arranged one for each conveyance path P in a direction intersecting (e.g., perpendicular to) the conveyance direction A2 in the horizontal plane, and are provided in the suction chamber 31f of the second printing device 30. The injection nozzles 42a, for example, inject gas (e.g., air) toward the conveyance belt 31a, causing the tablets T to fall from the conveyance belt 31a. At this time, the gas injected from the injection nozzle 42a passes through suction holes (similar to the suction holes 21g shown in FIG. 2) in the conveyance belt 31a and hits the tablets T. The injection nozzles 42a are electrically connected to the control device 50, and their driving is controlled by the control device 50.

[0037] The storage boxes 42b are provided directly below the spray nozzles 42a and below the conveying device 31. The storage boxes 42b receive and store tablets T that have fallen from the conveying belt 31a due to the gas sprayed from the spray nozzles 42a.

[0038] The spray nozzle 42a may be installed in a position other than inside the suction chamber 31f of the second printing device 30. For example, the spray nozzle 42a may be installed below the conveying device 31 so that gas is sprayed toward the side of the tablet T being conveyed by the conveying belt 31a. In this case, the spray nozzle 42a may be installed at an angle to the vertical direction. In this case, the storage box 42b is installed taking into consideration the gas spray direction of the spray nozzle 42a.

[0039] The non-defective product recovery device 43 has a gas blowing section 43a and a storage box (recovery box) 43b. The non-defective product recovery device 43 is provided downstream in the conveying direction A2 from the position where the reusable product recovery device 42 is provided, and the gas blowing section 43a is provided in common to each conveying path P.

[0040] The gas blowing section 43a is provided at the end of the conveying device 31 of the second printing device 30, i.e., at the end of the lower horizontal portion of the conveying belt 31a. For example, during the printing process, the gas blowing section 43a constantly blows gas (e.g., air) toward the conveying belt 31a, causing the tablets T to fall from the conveying belt 31a. At this time, the gas blown out from the gas blowing section 43a passes through suction holes (similar to the suction holes 21g shown in FIG. 2) in the conveying belt 31a and hits the tablets T. As the gas blowing section 43a, for example, an air blower having a slit-shaped opening extending in a direction intersecting (e.g., perpendicular to) the conveying direction A2 in the horizontal plane can be used. The gas blowing section 43a is electrically connected to the control device 50, and its drive is controlled by the control device 50.

[0041] Here, the tablets T that have passed through the defective product recovery device 41 and the reusable product recovery device 42 are transported along with the movement of the conveyor belt 31a, and reach a position near the end of the conveyor belt 31a on the side of each driven pulley 31c. At this position, the suction action no longer acts on the tablets T, and gas is blown onto the tablets T from above by the gas blowing section 43a, causing the tablets T to fall from the conveyor belt 31a. By providing the gas blowing section 43a, the tablets T are reliably allowed to fall from the conveyor belt 31a and fall toward the storage boxes 43b.

[0042] The control device 50 includes an image processing unit 51, a print processing unit 52, an inspection processing unit (inspection unit) 53, and a memory unit 54. The image processing unit 51 processes images. The print processing unit 52 performs processing related to printing. The inspection processing unit 53 performs processing related to inspection. The memory unit 54 stores various information such as processing information and various programs. Such a control device 50 controls the supply device 10, the first printing device 20, the second printing device 30, and the recovery device 40, and also receives position information of the tablets T transmitted from the individual detection devices 22 and 32 of the first printing device 20 and the second printing device 30, images transmitted from the individual imaging devices 23, 25, 33, and 35 of the first printing device 20 and the second printing device 30, the side imaging cameras SC1 of the first side image acquisition units SD1 and second side image acquisition units SD2, and the three-dimensional image imaging cameras C1 of the first three-dimensional image acquisition units 3D1 and second three-dimensional image acquisition units 3D2, etc. The operating conditions are set in advance and stored in the storage unit 54. The control device 50 controls each processing unit and the recovery device 40 based on the operating conditions stored in the storage unit 54.

[0043] Next, the print processing unit 52, the inspection processing unit 53, and the collection operation of the collection device 40 will be described. The image processing unit 51 processes images of tablets T captured by the first imaging devices 23, 33, the second imaging devices 25, 35, the first side image acquisition unit SD1, the second side image acquisition unit SD2, the first three-dimensional image acquisition unit 3D1, and the second three-dimensional image acquisition unit 3D2, and sends them to the inspection processing unit 53. The inspection processing unit 53 detects tablets T that have become defective due to printing defects or tablets T that have become defective due to having a defective appearance from these images. The defective product collection device 41 collects tablets T that have been determined to be "defective" by the inspection processing unit 53. Of these, tablets T that have been detected as defective upstream of the print head device 24 on the conveying path P (i.e., based on images captured by the first imaging device 23 and the first side image acquisition unit SD1) are not printed by the print head device 24 and are collected by the defective product collection device 41. Similarly, if a defect is detected by the first imaging device 23, printing is not performed by the print head device 34 and the tablets are collected by the defective product collecting device 41. The reused product collecting device 42 collects tablets T that are not cracked, chipped, or dirty but for which printing was not performed due to reasons such as poor posture of the tablets T. The posture of the tablets T is determined by the inspection processing unit 53 based on images captured by the first imaging device 23, first side image acquisition unit SD1, etc., upstream of the print head device 24 on the conveying path P. In the defective product collecting device 41 and the reused product collecting device 42, the tablets are collected into a defective product collecting box 41b and a reused product collecting box 42b by the spray nozzle 41a and the spray nozzle 42a, respectively, and the tablets T not collected here are collected into a non-defective product collecting box 43b.

[0044] (Printing process) Next, we will explain the printing process and inspection process performed by the above-mentioned tablet printing apparatus 1. In the following printing process, we will explain double-sided printing, in which identification information is printed on both sides of a tablet T that has a score line formed on one side so that it is aligned with the score line (for example, parallel to the extension direction of the score line).

[0045] First, various information such as print data required for printing is stored in the memory unit 54 of the control device 50. Then, 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, which then arranges them in two rows and moves them. The tablets T moving in these two rows are sequentially supplied to the conveyor belt 21a of the first printing device 20 by the delivery feeder 13. The conveyor belt 21a rotates in the conveying direction A1 by the rotation of the drive pulley 21b and each driven pulley 21c driven by the motor 21d. Therefore, the tablets T supplied onto the conveyor belt 21a are conveyed in two rows on the conveyor belt 21a at a predetermined moving speed. The conveyor belt 31a also rotates in the conveying direction A2 by the rotation of the drive pulley 31b and each driven pulley 31c driven by the motor 31d.

[0046] In the first printing device 20, the tablet T is suction-held on the conveyor belt 21a, and the tablet T on the conveyor belt 21a is detected by the detection device 22. As a result, position information of the tablet T (position in the conveying direction A1) is acquired and input to the control device 50. This position information of the tablet T is stored in the memory unit 54 and used in post-processing. Next, the tablet T on the conveyor belt 21a is imaged by the first imaging device 23 at a timing based on the position information of the tablet T described above, and the captured image is transmitted to the control device 50. Based on each image transmitted from the first imaging device 23, positional deviation information of the tablet T (for example, positional deviation of the tablet T in the X direction, Y direction, and θ direction in FIG. 2) is generated by the image processing unit 51 and stored in the memory unit 54. Based on this positional deviation information of the tablet T, printing conditions for the tablet T (such as the ink ejection position and ejection speed) are set by the print processing unit 52 and stored in the memory unit 54.

[0047] Next, the tablets T on the conveyor belt 21a are imaged by the side image capturing camera SC1 of the first side image capturing unit SD1. As shown in FIGS. 3A and 3B, the first side image capturing unit SD1 is illuminated by a ring light R, and light reflected by the side of the tablet T enters the first reflecting mirror M1, the light reflected by the first reflecting mirror M1 enters the second reflecting mirror M2, and the light reflected by the second reflecting mirror M2 enters the side image capturing camera SC1 via a lens (not shown), thereby capturing an image of the side of the tablet T. The side image of the tablet T captured by the side image capturing camera SC1 is transmitted to the control device 50. As shown in FIG. 3B, eight first reflecting mirrors M1 and eight second reflecting mirrors M2 are arranged (the number of mirrors is not limited to eight and may be more or less than this). In other words, the side image capturing camera SC1 captures images of the side of the tablet T from eight directions as a single image. The side image captured by the side image capturing camera SC1 and transmitted to the control device 50 is processed by the image processing unit 51, and a determination is made as to whether or not the tablet is defective by the inspection processing unit 53. As a result, tablets T that are determined to be non-defective undergo subsequent printing processing, while tablets that are determined to be defective are collected by the defective product collecting device 41 without undergoing subsequent printing processing.

[0048] Next, printing is performed on each tablet T on the conveyor belt 21a by the print head device 24 based on the above-mentioned print data and printing conditions at a timing based on the position information of the tablet T, i.e., at the timing when the tablet T reaches below the print head device 24. In each print head 24a of the print head device 24, ink is appropriately ejected from each nozzle 24b, and identification information such as letters (e.g., alphabets, katakana, numbers) and marks (e.g., symbols, figures) is printed on the top surface of the tablet T aligned with the score line (e.g., parallel to the extension direction of the score line).

[0049] The tablet T on which the identification information is printed is imaged by the second imaging device 25 at a timing based on the position information of the tablet T described above, and the imaged image is transmitted to the control device 50. Based on the individual images transmitted from the second imaging device 25, printing position information indicating the printing position of the printing pattern for each tablet T is generated by the image processing unit 51 and stored in the memory unit 54. Based on the printing position information, the inspection processing unit 53 determines whether the printing quality of each tablet T (whether the tablet T is a good product or not), and inspection result information indicating the quality of the printing for each tablet T and the quality of the appearance, such as cracks and chips, is stored in the memory unit 54. For example, the inspection processing unit 53 determines whether the printing pattern is printed in a predetermined pattern at a predetermined position on the tablet T. A tablet T that is determined to have a printing pattern printed in a predetermined pattern at a predetermined position on the tablet T is deemed to be a good tablet T that has passed the inspection, and the subsequent printing process continues.

[0050] Thereafter, the external shape of the tablet T is imaged by the three-dimensional image capturing camera C1 of the first three-dimensional image acquisition unit 3D1. The image captured by the three-dimensional image capturing camera C1 is sent to the control device 50, and is processed by the image processing unit 51 to generate a three-dimensional image. Based on this image, the inspection processing unit 53 determines whether or not the tablet is defective. As a result, tablets T that are determined to be good undergo subsequent printing processing, while tablets that are determined to be defective are collected by the defective product collection device 41 without undergoing subsequent printing processing.

[0051] The tablet T that has passed through the first three-dimensional image acquisition unit 3D1 is transported along with the movement of the conveyor belt 21a and passes above the drying device 26 that is in a drying operation. At this time, the ink that has reached (landed on) the tablet T is dried by the drying device 26 while the tablet T passes above the drying device 26, and the tablet T with the dried ink is transported along with the movement of the conveyor belt 21a and is positioned near the end of the conveyor belt 21a on the side of each driven pulley 21c. At this position, the suction effect no longer acts on the tablet T, and the tablet T is released from being held on the lower surface of the conveyor belt 21a and is passed from the first printing device 20 to the second printing device 30.

[0052] In the second printing device 30, tablets T are also suction-held on the conveyor belt 31a, and printing and inspection processes are performed in the same manner as described above. However, in the second printing device 30, after the tablets T are imaged by the second imaging device 35, they pass through the second three-dimensional image acquisition unit 3D2 and the second side image acquisition unit SD2 in that order. The tablets T are transported along with the movement of the conveyor belt 31a and pass above the drying device 36, which is in a drying operation. Then, tablets T with dried ink reach the defective product recovery device 41. At this position, tablets T other than non-defective (defective or unknown) fall from the underside of the conveyor belt 31a due to the gas injection (blowing) from the injection nozzle 41a and are collected in the storage box 41b. In addition, tablets T that could not be printed due to poor posture or other reasons are collected in the reused product recovery device 42. Good tablets T (i.e., tablets T not collected by the defective product collecting device 41 or the reusable product collecting device 42) pass through the defective product collecting device 41 and the reusable product collecting device 42 and reach a position near the end of the conveyor belt 31a on the driven pulley 31c side. At this position, the suction action no longer acts on the tablets T, and they fall. Furthermore, gas is blown onto the tablets T from above by the gas blowing section 43a, so that the tablets T fall reliably from the conveyor belt 31a. The tablets T that have fallen from the conveyor belt 31a are collected in the storage box 43b.

[0053] (Side inspection) Here, the side surface inspection of the tablet T will be described. First, in the first printing device 20, before printing is performed by the print head device 24, the first side surface image acquisition unit SD1 performs side surface inspection of the tablet T. The side surface inspection here determines whether there is any dirt, chipping, cracks, etc. on the side surface of the tablet T (by the inspection processing unit 53). If the inspection processing unit 53 determines that there is dirt, chipping, or cracking, the tablet T is determined to be a defective product, and printing is not performed by the print head device 24 and the print head device 34 of the second printing device 30, and the tablet T is collected as a defective product by the defective product collection device 41. In other words, by inspecting the side surface of the tablet T before printing processing, unnecessary ink consumption can be eliminated.

[0054] Next, in the second printing device 30, after printing is performed by the print head device 34, a side surface inspection of the tablet T is performed by the second side surface image acquisition unit SD2. The side surface inspection here inspects the side surface of the tablet T for stains, chips, and cracks, including ink stains that adhere to the tablet T as the tablet T passes through the print head devices 24, 34. In rare cases, ink may scatter and adhere to the side surface of the tablet T when it passes through the print heads 24, 34. By performing a side surface inspection of the tablet T after it has passed through the print head device 34, it is possible to inspect for such stains as well. Furthermore, as shown in FIG. 5, the second side surface image acquisition unit SD2 of the second printing device 30 images the side surface of the tablet T that is suction-held on the curved surface portion of the conveyor belt 31a (the curved surface portion of the drive pulley 31a). Therefore, unlike the imaging by the first side surface image acquisition unit SD1 of the first printing device 20, it is possible to inspect up to the edge of the surface side of the tablet T that contacts the conveyor belt 31a. The edge portions of tablets are the parts most susceptible to chipping, and chipping can occur when tablets collide with other tablets or with some component of the tablet printing device 1 during transport. However, the second side image acquisition unit SD2 can inspect the sides, including the edge portions on both sides, of tablets T that have been transported through each part of the tablet printing device 1.

[0055] (3D inspection) The first 3D image acquisition unit 3D1 and the second 3D image acquisition unit 3D2 are provided on the side wall of the housing B of the tablet printing apparatus 1. That is, they are provided in a position where they will not interfere with other components when a mechanism for dissipating heat from the side wall to 3D1 and 3D2 is attached. As described above, the first 3D image acquisition unit 3D1 and the second 3D image acquisition unit 3D2 are constantly irradiated with laser light from the laser light irradiation units L1 and L2 during device operation in order to perform inspection using the light section method. Therefore, they are among the components of the tablet printing apparatus 1 that are most susceptible to heat generation. The tablet printing apparatus 1 is provided with print head devices 24 and 34. If the temperature inside the apparatus exceeds 30°C, the print heads 24 and 34 may malfunction and become unusable. Furthermore, as the temperature inside the tablet printing apparatus 1 increases, the viscosity of the ink supplied to the print heads 24 and 34 decreases, resulting in poor ejection (ejection of more ink than specified), which can lead to poor printing on the tablets T. By providing the first 3D image acquisition unit 3D1 and the second 3D image acquisition unit 3D2 on the side wall side of the housing B, heat can be easily dissipated outside the device, preventing malfunctions of the print heads 24 and 34 and preventing printing defects. For example, a cooling fan CF1 (cooling means) is provided downstream in the transport direction A1 (on the right side of the drawing) of the first 3D image acquisition unit 3D1 shown in FIG. 1, and supplies cooling air supplied from outside the side wall W1 to the first 3D image acquisition unit 3D1. A cooling fan CF2 (cooling means) is also provided downstream in the transport direction A2 of the three-dimensional image acquisition unit 3D2 (on the left side of the drawing) above the second side image acquisition unit SD2, and supplies cooling air from outside the side wall W2 to the second 3D image acquisition unit 3D2. By providing the first three-dimensional image acquisition unit 3D1 and the second three-dimensional image acquisition unit 3D2 on the side walls W1 and W2 in this manner, it is possible to prevent the cooling air from being heated before it is supplied to the first three-dimensional image acquisition unit 3D1, which is the object to be cooled, and cooling efficiency is improved, compared to when the first three-dimensional image acquisition unit 3D1 is provided upstream of the print head device 24 in the conveying direction A1, for example.Similarly, compared to when the three-dimensional image acquisition unit 3D2 is located upstream of the print head device 34 in the transport direction A2, this prevents the cooling air from being heated before it is supplied to the second three-dimensional image acquisition unit 3D2, which is the target to be cooled, resulting in better cooling efficiency. In other words, only the cooling fan CF1 is provided in the area between the first three-dimensional image acquisition unit 3D1 and the sidewall W1 of the housing B closest to the first three-dimensional image acquisition unit 3D1 (of the two sidewalls facing each other in the transport direction A1, the sidewall on the right side of the paper in FIG. 1). Other components (particularly the print head 24) are provided elsewhere (in the area upstream of the three-dimensional image acquisition unit 3D1). Similarly, in the second three-dimensional image acquisition unit 3D2, no components such as the print head 34 are provided in the area between sidewall W2, which is the sidewall of the housing B closer to the three-dimensional image acquisition unit 3D2 (of the two sidewalls facing each other in the direction along the transport direction A1, the sidewall on the left side of the paper in FIG. 1), but instead a cooling fan CF2 and a second side image acquisition unit SD2 are provided. The second side image acquisition unit SD2 is provided in a position (below the cooling fan CF2) where it will not interfere with the sidewall W2 and the three-dimensional image acquisition unit 3D2.

[0056] Furthermore, the first three-dimensional image acquisition unit 3D1 is provided downstream of the print head 24, and the second three-dimensional image acquisition unit 3D2 is provided downstream of the print head 34, both of which are provided to face the tablet T being transported on the horizontal plane. As a result, even if the tablet T collides with the print heads 24, 34 as it passes below them, causing chipping or cracking, this can be detected by the first three-dimensional image acquisition unit 3D1 and the second three-dimensional image acquisition unit 3D2, and the tablet can be ejected as a defective product. Furthermore, because the tablet T being transported on the horizontal plane is detected, the three-dimensional shape can be accurately detected.

[0057] If the nozzles 24b of the print head device 24 dry out, the ink near the nozzles 24b may dry out and solidify, leading to ejection problems. To prevent this, the suction force applied to the suction holes 21g on the conveyor belt 21a facing the print head device 24 may be reduced to prevent the nozzles 24b from being affected by airflow. For example, a shielding plate that blocks part of the suction holes 21g on the upper surface of the suction chamber 21f may be provided to reduce the suction force acting below the print head device 24. Since the suction force applied to tablets T conveyed through this area is reduced, strong suction force is not applied to a portion of the tablets T, reducing the likelihood that tablets T will be held in an upright position if they are R-shaped. It is preferable that the area where suction force is reduced includes not only the area directly below the print head device 24 but also the area from the detection device 22 to below the first three-dimensional image acquisition unit 3D1. This enables detection, imaging, and printing of tablets T while maintaining the same orientation. Also, in the first three-dimensional image acquisition unit 3D1, the tablet T can be prevented from taking the upright posture described above, so that the outer shape of the tablet T can be acquired accurately.

[0058] As described above, according to the first embodiment, the first side image acquisition unit SD1, the second side image acquisition unit SD2, the first three-dimensional image acquisition unit 3D1, and the second three-dimensional image acquisition unit 3D2 are each provided in appropriate positions, thereby enabling good visual inspection and printing inspection of tablets.

[0059] <Second embodiment> The second embodiment will be described with reference to Fig. 6. Note that in the second embodiment, differences from the first embodiment (the position of the three-dimensional image acquisition unit and the presence or absence of a cooling fan) will be described, and other descriptions will be omitted.

[0060] As shown in FIG. 6, in the second embodiment, the first 3D image acquisition unit 3D1 and the second 3D image acquisition unit 3D2 are provided below the first conveyance device 21 and the second conveyance device 31, respectively. By providing the 3D image acquisition units below the conveyance devices in this manner, heat generated by the 3D image acquisition units can be prevented from reaching the print head device. For example, the first printing device 20 and the second printing device 30 are provided as close as possible to each other so that the distance between them is approximately 0.2 mm above the tablet thickness in the vertical direction in order to transfer tablets T having a thickness of approximately 2 to 3 mm without causing cracks or chips. In other words, within the housing B, the left and right sides of the paper in FIG. 6 are almost entirely blocked from passing air between the transfer portion of tablets T between the first printing device 20 and the second printing device 30. Therefore, heat generated by the first 3D image acquisition unit 3D1 can be prevented from reaching the print head device 34.

[0061] Furthermore, the drying devices 26, 36 can also serve as a drying device for drying the ink on the tablets T and as a cooling means for the three-dimensional image acquisition unit. For example, the drying device 26 is provided upstream of the first three-dimensional image acquisition unit 3D1 in the conveying direction A1, and cool air is supplied from this drying device 26. The cool air from the drying device 26 is supplied toward the conveyor belt 21a and the first three-dimensional image acquisition unit 3D1 located downstream. The drying device 36 of the second conveying device 31 also supplies cool air toward the conveyor belt 31a and the second three-dimensional image acquisition unit 3D2 located downstream in the conveying direction A2.

[0062] As described above, according to the second embodiment, it is possible to obtain the same effects as those of the first embodiment. Furthermore, since the drying devices 26 and 36 can serve both as drying devices that dry the tablets T and as cooling means for the first three-dimensional image acquisition unit 3D1 and the second three-dimensional image acquisition unit 3D2, it is possible to cool the three-dimensional image acquisition unit without providing an additional cooling fan.

[0063] <Other embodiments> In the above explanation, an example was given in which the tablets T were transported in two rows, but this is not limited to this, and the number of rows may be one, three, four or more, and the number of transport paths P and the number of transport belts 21a, 31a are not particularly limited. Furthermore, the shape of the suction holes 21g of the transport belts 21a, 31a is not particularly limited.

[0064] In addition, in the above explanation, an example was given of providing a print head 24a for each conveying path P, but this is not limited to this, and for example, one print head 24a may be used to print on two or more rows of tablets T.

[0065] In the above description, a print head with nozzles 24b arranged in a single row was used as an example of the inkjet print head 24a, but this is not limited to this, and for example, a print head with nozzles 24b arranged in multiple rows may also be used.Furthermore, multiple print heads 24a may also be lined up along the transport direction A1.

[0066] In addition, although the above description exemplifies the provision of the drying devices 26 and 36, the number of drying devices is not limited. For example, only one of the drying devices 26 and 36, or neither of the drying devices 26 and 36, may be provided.

[0067] In addition, in the above explanation, the second side image acquisition unit SD2 is illustrated as being located downstream of the second three-dimensional image acquisition unit 3D2, but this is not limited to this, and the side image acquisition unit may be arranged in that order, followed by the three-dimensional image acquisition unit, as in the first printing device 20.

[0068] In addition, in the above explanation, an example was given of detecting cracks and chips using the first imaging device 23, 33 and the first side image acquisition unit SD1, but this is not limited to this. It is also possible to detect cracks and chips using a three-dimensional image acquisition unit downstream of the print head device 24, 34, and have the first imaging device 23, 33 and the first side image acquisition unit SD1 perform processing to detect only dirt on the tablet.

[0069] In addition, in the above explanation, the first three-dimensional image acquisition unit 3D1 and the second three-dimensional image acquisition unit 3D2 are exemplified as being arranged so that their horizontal surfaces face the tablet T being transported, but this is not limited to this, and they may also be arranged so that their curved surfaces face the tablet T being transported.

[0070] In the above description, the three-dimensional image capturing camera C1 is provided downstream of the laser light emitting unit L1 in the conveying direction A1, but the present invention is not limited to this and may be provided upstream.

[0071] In the above description, the side image acquisition unit SD2 in the second printing device 30 is additionally provided with a third reflecting mirror M3 with 90-degree polarization and a side image capturing camera SC1 polarized at 90 degrees, but the present invention is not limited to this. For example, the third reflecting mirror M3 may be omitted, and the side image capturing camera SC1 may be provided on the optical path of the first reflecting mirror M1 and the second reflecting mirror M2.

[0072] In the above description, the cooling method for the first three-dimensional image acquisition unit 3D1 and the second three-dimensional image acquisition unit 3D2 is exemplified by supplying cooling air from the outside of the side walls W1, W2 and supplying it to the three-dimensional image acquisition units 3D1, 3D2 by a cooling fan, but this is not limited to this. For example, air may be blown onto the three-dimensional image acquisition units 3D1, 3D2 from the top surface of the tablet printing apparatus 1, and heat may be discharged together with the air from the side walls W1, W2 to the outside. Furthermore, the cooling means may be attached to a part other than the wall surface (for example, the interior of the tablet printing apparatus 1).

[0073] In addition, in the above explanation, an example was given of arranging the first printing device 20 and the second printing device 30 one on top of the other to print on both sides or one side of the tablet T, but this is not limited to this, and for example, it is also possible to provide only the first printing device 20 and print on only one side of the tablet T.

[0074] In addition, in the above explanation, an example was given in which the reusable product recovery device 42 is provided downstream of the defective product recovery device 41, but this is not limited to this, and it may also be provided upstream of the defective product recovery device 41.

[0075] Furthermore, although the above description does not specifically mention the suction force of the suction chambers 21f and 31f, the suction force may be reduced only near the nozzles of the print head devices 24 and 34 to prevent them from drying out. When changing the suction force in this manner, it is preferable to maintain the same suction force from the detection device 22 to the first three-dimensional image acquisition unit 3D1 to avoid changing the transport position of the tablet T, which could interfere with accurate printing and inspection. Similarly, in the second printing device 30, it is preferable to maintain the same suction force from the detection device 32 to the second three-dimensional image acquisition unit 3D2. Note that the second side image acquisition unit must apply a suction force to the tablet T that is strong enough to counter the centrifugal force of the pulley 31b, and therefore must have a suction force stronger than the suction force reduced below the print head device 34.

[0076] In addition, in the above description, the tablet printing device 1 is entirely enclosed by the housing B, but this is not limiting, and a part of it, such as a collection box, may be located outside the housing B.

[0077] Here, the aforementioned tablets T can include tablets used for pharmaceutical, edible, cleaning, industrial, or aromatic purposes. Tablets 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. Tablet shapes include discs, lenses, triangles, ovals, and other shapes. When the tablets to be printed are for pharmaceutical or edible use, edible ink is preferably used. The edible ink may be any of synthetic pigment ink, natural pigment ink, dye ink, and pigment ink.

[0078] 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, and modifications 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]

[0079] 1. Tablet printing equipment SD1 First side image acquisition unit SD2 Second side image acquisition unit 3D1 First three-dimensional image acquisition unit 3D2 Second 3D image acquisition unit 31a Conveyor belt 34 Print head device 41 Defective product recovery device 42 Re-inspection product collection device 42b Storage Box 43 Good product recovery device 50 Control device (control unit) 51 Image processing section 53 Inspection Processing Section (Inspection Section) CF1, CF2 cooling fans T tablets

Claims

1. A tablet printing device enclosed in a rectangular housing that prints identification information on tablets by ejecting ink from a print head device onto the tablets, a supply device for supplying the tablets; a first printing device that conveys the tablets supplied from the supply device by a first conveyor belt and performs a printing process on one side of the tablets; a second printing device that conveys the tablet received from the first printing device by a second conveyor belt and performs printing processing on the other side of the tablet; and The housing includes a first side wall and a second side wall that face each other in a conveying direction of the tablets by the first conveyor belt, the supply device and the second printing device are provided on the first side wall side so as to be aligned vertically, the first printing device is provided on the second sidewall at a higher position than the second printing device, the first printing device has a first print head device that prints on the one side of the tablet, and a first three-dimensional image acquisition unit that is provided between the first print head device and the second side wall and that acquires a three-dimensional image of the tablet printed by the first print head device; The second printing device has a second print head device that prints on the other side of the tablet, and a second three-dimensional image acquisition unit that is provided between the second print head device and the first side wall and that acquires a three-dimensional image of the tablet printed by the second print head device, the first three-dimensional image acquisition unit and the second three-dimensional image acquisition unit each have a laser light irradiation unit and a three-dimensional image capturing camera; a control device that controls the first print head device, the second print head device, the first three-dimensional image acquisition unit, and the second three-dimensional image acquisition unit; The control device processes the three-dimensional images obtained by the first three-dimensional image acquisition unit and the second three-dimensional image acquisition unit, and performs an appearance inspection of the tablet, a first cooling unit provided on the second side wall and configured to supply gas to the first three-dimensional image acquisition unit; A tablet printing apparatus having a second cooling means provided on the first side wall and supplying gas to the second three-dimensional image acquisition unit.

2. A first side image acquisition unit that acquires an image of the side of the tablet upstream of the first print head device; a second side image acquisition unit that acquires an image of the side of the tablet downstream of the second print head device; a recovery device that recovers the tablets downstream of the second side image acquisition unit, The tablet printing device described in claim 1, characterized in that the control device inspects the appearance of the tablet based on the images acquired by the first side image acquisition unit and the second side image acquisition unit, controls printing by the first print head based on the inspection results of the image acquired by the first side image acquisition unit, and controls collection by the collection device based on the inspection results of the image acquired by the second side image acquisition unit.

Images