Conveyor and Processing Equipment

Abstract

To provide a conveyance and processing apparatus capable of suppressing deterioration of printing quality.SOLUTION: A conveyance and processing apparatus conveys a plurality of tablets to perform a predetermined process. The conveyance and processing apparatus comprises: a conveyor belt which has a plurality of suction holes on an external surface and conveys tablets along a predetermined conveyance passage while making a negative pressure act on the suction holes to suck and hold the tablets; a gas blowing part for blowing gas toward the external surface of the conveyor belt; and a suction mechanism for sucking powder of the tablets blown off from the external surface by blowing the gas to the external surface. The apparatus further comprises: a camera for photographing the tablets conveyed by the conveyor belt at an inspection position on the conveyance passage; and an inspection processing unit for inspecting the tablets based on the image photographed by the camera. The gas blowing part and the suction mechanism, on an upstream side of the inspection position on the conveyance passage, blow gas toward the external surface of the conveyor belt, and suck the powder of the tablets blown off from the external surface.SELECTED DRAWING: Figure 15

Description

[Technical field]

[0001] An embodiment of the present invention relates to a transport and processing device. [Background technology]

[0002] Typically, a tablet printing device is a device that prints identification information such as characters (e.g., alphabets, katakana, numbers) and marks (e.g., symbols, figures) on the surface of a tablet in order to identify the tablet. As such tablet printing devices, tablet printing devices that print on transported tablets using a transfer drum method or inkjet method have been developed. An inkjet type tablet printing device ejects ink (e.g., edible ink) toward the tablet while transporting the tablet on a transport belt, and prints identification information on the tablet surface.

[0003] Among such tablet printing devices, there is one equipped with a tablet conveying device that holds and conveys tablets on a conveying belt by suction force. The conveying belt has a plurality of suction holes arranged in the direction of conveying the tablets for adsorbing the tablets. Furthermore, a suction chamber having suction slits formed all around is provided facing the surface (back surface) of the conveying belt opposite the tablet holding surface, and the tablets on the conveying belt are held on the conveying belt by suction force applied through each suction hole of the conveying belt and the suction slits of the suction chamber.

[0004] Meanwhile, the conveyor belt moves to convey the tablets, while the suction chamber is fixedly disposed in the device. Therefore, the back surface of the conveyor belt moves in contact with the suction chamber. Furthermore, the suction force applied by the suction chamber to the suction holes also acts as a force that attracts the back surface of the conveyor belt toward the suction chamber, and the contact force between the back surface of the conveyor belt and the suction chamber increases. If the frictional force between the suction chamber and the conveyor belt increases with the increase in this contact force, the conveyor belt may not move smoothly and may vibrate. This may cause the tablets on the conveyor belt to shake, resulting in a decrease in print quality (for example, print misalignment or fainting). [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 6-143539 Summary of the Invention [Problem to be solved by the invention]

[0006] The problem to be solved by the present invention is as follows: A conveyor and processing device that can remove foreign matter adhering to a conveyor belt The purpose of this project is to provide [Means for solving the problem]

[0007] A conveying processing device according to an embodiment of the present invention is a conveying processing device that conveys multiple tablets and performs a predetermined processing, and includes a conveying belt having multiple suction holes on its outer surface, which applies negative pressure to the suction holes to adsorb and hold the tablets while conveying them along a predetermined conveying path, a gas blowing section that blows gas toward the outer surface of the conveying belt, and a suction mechanism that sucks up tablet powder blown off from the outer surface by blowing the gas onto the outer surface, and further includes a camera that photographs the tablets conveyed by the conveying belt at an inspection position on the conveying path, and an inspection processing section that inspects the tablets based on the image captured by the camera, and the gas blowing section and the suction mechanism blow the gas toward the outer surface of the conveying belt upstream of the inspection position on the conveying path, and suck up the tablet powder blown off from the outer surface. Effect of the Invention

[0008] According to an embodiment of the present invention, Remove any dirt adhering to the conveyor belt It is possible. [Brief description of the drawings]

[0009] [Figure 1] 1 is a diagram showing a schematic configuration of a tablet printing apparatus according to a first embodiment. [Diagram 2]FIG. 1 is a plan view showing a transport device according to a first embodiment. [Diagram 3] 2 is a perspective view showing a chamber, a suction pipe, and a pulley body of the conveying device according to the first embodiment. FIG. [Figure 4] 4 is a cross-sectional view taken along line 4-4 of FIG. 1. [Diagram 5] 5 is a cross-sectional view taken along line 5-5 of FIG. 1. [Figure 6] FIG. 4 is a diagram for explaining a suction state of the transport device according to the first embodiment. [Figure 7] FIG. 11 is a perspective view showing a pulley body according to a second embodiment. [Figure 8] 8 is a cross-sectional view taken along line 8-8 in FIG. 7. [Figure 9] FIG. 11 is a cross-sectional view showing a pulley body according to a third embodiment. [Figure 10] FIG. 13 is a diagram showing a part of a tablet printing apparatus according to a fourth embodiment. [Figure 11] FIG. 13 is a diagram showing a part of a tablet printing apparatus according to a fifth embodiment. [Figure 12] FIG. 13 is a plan view showing an attraction force reducing member according to a fifth embodiment. [Figure 13] 13A to 13C are diagrams for explaining various comparison results between the suction chamber according to the fifth embodiment and a normal suction chamber. [Figure 14] FIG. 13 is a diagram showing a part of a tablet printing apparatus according to a sixth embodiment. [Figure 15] FIG. 13 is a diagram showing a part of a tablet printing apparatus according to a seventh embodiment. [Figure 16] 16 is a cross-sectional view taken along line 16-16 in FIG. 15. [Figure 17] FIG. 13 is a diagram showing a first modified example of the gas suction part according to the seventh embodiment. [Figure 18] FIG. 13 is a diagram showing a second modified example of the gas suction part according to the seventh embodiment. [Figure 19] FIG. 13 is a diagram showing a third modified example of the gas suction part according to the seventh embodiment. [Figure 20] 20 is a cross-sectional view taken along line 20-20 of FIG. 19. [Figure 21]13A and 13B are diagrams showing modified examples of the cover according to the seventh embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] <First embodiment> The first embodiment will be described with reference to FIGS.

[0011] (Basic configuration) 1, the tablet printing device 1 according to the first embodiment includes a supply device 10, a first printing device 20, a second printing device 30, a collection device 40, and a control device 50. The first printing device 20 and the second printing device 30 basically have the same structure.

[0012] The supply device 10 has a hopper 11, an alignment feeder 12, and a transfer 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 conveys them toward the transfer feeder 13. The transfer feeder 13 sequentially sucks up the tablets T on the alignment feeder 12, conveys them in two rows to the first printing device 20, and supplies them to the first printing device 20 in two rows. The supply device 10 is electrically connected to the control device 50, and its drive is controlled by the control device 50. In addition, as the alignment feeder 12 and the transfer feeder 13, for example, a belt conveying mechanism can be used.

[0013] The first printing device 20 includes a conveying device (tablet conveying device) 21, a detection device 22, a first imaging device (imaging device for printing) 23, a print head device 24, a second imaging device (imaging device for inspection) 25, and a drying device 26.

[0014] The conveying device 21 includes a conveying belt 21a, a pulley body 21b (first rotating body) which is a driving pulley, a plurality of (three in the example of FIG. 1) driven pulleys 21c (second rotating bodies), a motor (driving unit) 21d, a position detector 21e, and a chamber 21f. The conveying belt 21a is formed in an endless shape and is stretched over the pulley body 21b and each driven pulley 21c. The pulley body 21b and each driven pulley 21c are rotatably provided on the device body, and the pulley body 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. This 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. In this conveying device 21, the conveying belt 21a is rotated together with each driven pulley 21c by the rotation of the pulley body 21b by the motor 21d, and the tablets T on the conveying belt 21a are conveyed in the direction of the arrow A1 in Figs. 1 and 2 (conveying direction A1).

[0015] Here, 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 the tablets T, and are arranged in two parallel rows along the conveying direction A1 to form two conveying paths. Each suction hole 21g is connected to a chamber 21f, and a suction force can be obtained from the chamber 21f. This chamber 21f is a chamber for applying (applying) a suction force to the tablets T placed in each suction hole 21g of the conveyor belt 21a (will be described in detail later).

[0016] 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 by one for each conveyance path of the tablets T downstream of the position where the tablets T are supplied on the conveyor belt 21a by the supply device 10 in the conveying direction A1 and in a direction intersecting (for example, perpendicular to) the conveying direction A1 in a horizontal plane, and are provided above the conveyor belt 21a. The detection units 22a detect the position of the tablets T on the conveyor belt 21a (position in the conveying direction A1) by projecting and receiving laser light, and function as a trigger sensor for each device located downstream. As the detection unit 22a, various laser sensors such as a reflective laser sensor can be used. Each detection unit 22a is electrically connected to the control device 50 and transmits a detection signal to the control device 50.

[0017] 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 one by one for each conveying path of the tablets T in a direction that is downstream of the position where the detection device 22 is provided and crosses the conveying direction A1 in a horizontal plane (for example, a direction perpendicular to the conveying direction A1), and are provided above the conveying belt 21a. Based on the position information of the tablet T described above, the imaging unit 23a performs imaging at the timing when the tablet T reaches directly below the imaging unit 23a, obtains an image including the upper surface of the tablet T (image for printing), and transmits the obtained image to the control device 50. As the imaging unit 23a, various cameras having imaging elements such as a CCD (charge-coupled device) or a CMOS (complementary metal oxide semiconductor) can be used. Each imaging unit 23a is electrically connected to the control device 50, and the driving thereof is controlled by the control device 50. In addition, illumination for imaging is also provided as necessary.

[0018] The print head device 24 has a plurality of inkjet print heads 24a (two in the example of FIG. 2). The print heads 24a are arranged downstream of the position where the first imaging device 23 is provided in the conveying direction A1, in a direction intersecting (for example, perpendicular to) the conveying direction A1 in a horizontal plane, one for each conveying path of the tablets T, and are provided above the conveying belt 21a. The print head 24a has a plurality of nozzles 24b (see FIG. 2: only four are shown in the figure), and ejects ink from each of the nozzles 24b. The print head 24a is provided so that the alignment direction of the nozzles 24b intersects (for example, perpendicular to) the conveying direction A1 in a horizontal plane. As the print head 24a, various inkjet print heads having driving elements such as piezoelectric elements, heating elements, or magnetostrictive elements can be used. Each print head 24a is electrically connected to the control device 50, and the driving of each of the print heads is controlled by the control device 50.

[0019] 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 one by one for each conveying path of the tablets T in a direction that is downstream of the position where the print head device 24 is provided and crosses the conveying direction A1 in a horizontal plane (for example, a direction perpendicular to the conveying direction A1), and are provided above the conveying belt 21a. Based on the position information of the tablet T described above, the imaging unit 25a performs imaging at the timing when the tablet T reaches directly below the imaging unit 25a, obtains an image (image for inspection) including the upper surface of the tablet T, and transmits the obtained image to the control device 50. As the imaging unit 25a, various cameras having imaging elements such as CCD and CMOS can be used, as with the imaging unit 23a described above. Each imaging unit 25a is electrically connected to the control device 50, and the driving thereof is controlled by the control device 50. In addition, illumination for imaging is also provided as necessary.

[0020] The drying device 26 is positioned downstream in the conveying direction A1 from the position where the second imaging device 25 is provided, and is provided, for example, below the conveying device 21. This drying device 26 is a drying device common to the two rows of conveying paths, 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 heater that dries the object to be dried by radiant heat, or a blower that dries the object to be dried by warm air or hot air. The drying device 26 is electrically connected to the control device 50, and its drive is controlled by the control device 50.

[0021] The tablets T that have passed above the drying device 26 are transported 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.

[0022] 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, a second imaging device (imaging device for inspection) 35, and a drying device 36. The conveying device 31 includes a conveying belt 31a, a pulley body 31b which is a driving pulley, a plurality of (three in the example of FIG. 1) driven pulleys 31c, a motor (driving unit) 31d, a position detector 31e, and a chamber 31f. Each element constituting the second printing apparatus 30 has a structure basically the same as that of the corresponding component of the first printing apparatus 20 described above, and therefore the description thereof will be omitted. The conveying direction of the second printing apparatus 30 is the direction of the arrow A2 in FIG. 1 (conveying direction A2).

[0023] The recovery device 40 includes a defective product recovery device 41 and a non-defective product recovery device 42. The recovery device 40 is located downstream in the conveying direction A2 from the position where the drying device 36 of the second printing device 30 is provided, and the defective product recovery device 41 recovers defective tablets T, and the non-defective product recovery device 42 recovers non-defective tablets T.

[0024] The defective product recovery device 41 has an injection nozzle 41a and a storage unit 41b. The injection nozzle 41a is provided in the conveyor 31 of the second printing device 30, and injects gas (e.g., air) toward the tablets T (defective tablets T) conveyed by the conveyor belt 31a, causing the tablets T to fall from the conveyor belt 31a. At this time, the gas injected from the injection nozzle 41a passes through a suction hole (similar to the suction hole 21g shown in FIG. 2) of the conveyor belt 31a and hits the tablets T. The injection nozzle 41a is electrically connected to the control device 50, and its drive is controlled by the control device 50. The storage unit 41b receives and stores the tablets T that have fallen from the conveyor belt 31a.

[0025] The non-defective product collecting device 42 has a gas blowing section 42a and a storage section 42b. The non-defective product collecting device 42 is provided at a downstream side in the conveying direction A2 from the position where the defective product collecting device 41 is provided. The gas blowing section 42a is provided in the conveying device 31 of the second printing device 30 at an end of the conveying device 31, that is, at an end of each driven pulley 31c side of the conveying belt 31a. The gas blowing section 42a always blows gas (e.g., air) toward the conveying belt 31a during, for example, the printing process, and causes the tablets T to fall from the conveying belt 21a. At this time, the gas blown out from the gas blowing section 42a passes through the suction hole (similar to the suction hole 21g shown in FIG. 2) of the conveying belt 31a and hits the tablets T. As the gas blowing section 42a, for example, an air blower having a slit-shaped opening extending in a direction intersecting (e.g., perpendicular to) the conveying direction A2 in a horizontal plane can be used. The gas blowing section 42a is electrically connected to the control device 50, and its driving is controlled by the control device 50. The storage section 42b receives and stores the tablets T that have dropped from the conveyor belt 31a.

[0026] The tablets T that have passed through the defective product recovery device 41 are transported 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, but by providing the gas blowing section 42a, the tablets T can be reliably recovered from the conveyor belt 31a into the storage section 42b.

[0027] The control device 50 includes an image processing unit 51, a print processing unit 52, an inspection processing 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 receives position information of the tablets T transmitted from the individual detection devices 22, 32 of the first printing device 20 and the second printing device 30, images transmitted from the individual imaging devices 23, 25, 33, 35 of the first printing device 20 and the second printing device 30, and the like.

[0028] (Suction chamber) Next, the chamber 21f and pulley body 21b of the first printing device 20 will be described with reference to Figures 3 to 6. These chambers 21f and pulley body 21b form a suction chamber. The chamber 31f and pulley body 31b of the second printing device 30 are basically the same in configuration, so their description will be omitted.

[0029] As shown in FIG. 3, the chamber 21f includes a chamber body 61. In FIG. 3, the conveyor belt 21a is omitted. The chamber body 61 is formed, for example, in a rectangular parallelepiped housing. The end of the chamber body 61 on the pulley body 21b side is open and is formed to match the outer peripheral shape of the pulley body 21b. The chamber body 61 is connected to an intake device such as a pump (not shown) via a suction pipe 62, and the inside of the chamber body 61 is depressurized by the operation of the intake device. The suction pipe 62 is connected to approximately the center of the side surface (plane parallel to the conveying direction A1) of the chamber body 61. The intake device is electrically connected to the control device 50, and its drive is controlled by the control device 50.

[0030] As shown in Figs. 3 and 4, the chamber body 61 has a guide portion 61a. The guide portion 61a is formed on the upper and lower surfaces of the chamber body 61. The guide portion 61a is formed with a plurality of suction grooves 61b (two rows in Figs. 3 and 4) and a plurality of grooves 61c (three rows in Figs. 3 and 4) extending along the conveying direction A1 of the tablets T. The suction grooves 61b are formed for each conveying path of the tablets T so as to be located directly below each suction hole 21g of the conveying belt 21a when the conveying belt 21a is stretched over the pulley body 21b and each driven pulley 21c. A plurality of through holes 61d leading to the inside of the chamber body 61 are formed in the bottom surface of the suction groove 61b in the conveying direction A1 of the tablets T. Therefore, when the inside of the chamber body 61 is sucked, the suction force is applied to the tablets T on the suction holes 21g formed in each of the upper surface region and the lower surface region of the conveying belt 21a. The grooves 61c are provided to reduce the contact area between the chamber body 61 and the transport belt 21a.

[0031] As shown in FIGS. 3 and 5, the pulley body 21b has a pair of conveying pulleys 71, 72 and a pair of guide pulleys 73, 74.

[0032] The pair of conveying pulleys 71, 72 are positioned at both ends of the width direction of the conveying belt 21a (direction perpendicular to the conveying direction A1 in a horizontal plane) so as to be spaced apart from each other, and are fixed to the rotating shaft 21h of the motor 21d. These conveying pulleys 71, 72 rotate and move the conveying belt 21a in response to the rotation of the rotating shaft 21h of the motor 21d. When a geared belt is used as an example of the conveying belt 21a, geared pulleys (timing pulleys) are used as the conveying pulleys 71, 72.

[0033] Here, as shown in FIG. 3, the separation distance (gap a1 in the conveying direction A1) between the conveying pulley 71 and the chamber body 61 is, for example, within a range of 0.5 mm to 1.0 mm. This is set to be smaller than the thickness of the tablet T. This prevents the tablet T from entering the inside of the chamber body 61 or the pulley body 21b due to some factor. When the conveying pulley 71 is a geared pulley, the height and width of the teeth are determined so as to prevent the tablet T from entering the inside of the chamber body 61 or the pulley body 21b. The separation distance (gap a1 in the conveying direction A1) between the conveying pulley 72 and the chamber body 61 is also set in the same manner as the conveying pulley 71.

[0034] The pair of guide pulleys 73, 74 are positioned between and adjacent to the respective conveying pulleys 71, 72, and are fixed to the rotating shaft 21h of the motor 21d. Therefore, these guide pulleys 73, 74 also rotate together with the pair of conveying pulleys 71, 72 while contacting the conveying belt 21a in response to the rotation of the rotating shaft 21h of the motor 21d. In particular, the pair of guide pulleys 73, 74 are disposed opposite to each other apart in the extending direction of the rotating shaft 21h of the motor 21d, so that a space (internal space) is formed inside the pulley body 21b, and a slit-shaped through hole 70a extending in the rotating direction of the pulley body 21b is formed. As a result, the pulley body 21b has a slit-shaped through hole 70a which is a gap between the pair of guide pulleys 73, 74. The width of the slit-shaped through hole 70a is about several centimeters to several tens of centimeters. The internal space of the chamber main body 61 and the internal space of the pulley body 21b communicate with each other through the through hole 70a. The chamber body 61 and the suction pipe 62 function as a duct (air passage) for the pulley body 21b.

[0035] The guide pulley 73 has suction grooves 73a and 73b formed over the entire circumference of the guide pulley 73 so as to extend in the rotation direction of the guide pulley 73. The suction groove 73a is formed at a position facing the row of suction holes 21g of the conveyor belt 21a hung on the pulley body 21b. A plurality of through holes 73c are arranged in the bottom surface of the suction groove 73a in the rotation direction of the guide pulley 73 and formed over the entire circumference of the guide pulley 73. The diameter of these through holes 73c is, for example, about several millimeters. Similarly to the guide pulley 73, the guide pulley 74 has suction grooves 74a and 74b formed over the entire circumference of the guide pulley 74 so as to extend in the rotation direction of the guide pulley 74. A plurality of through holes 74c are also arranged in the bottom surface of the suction groove 74a in the rotation direction of the guide pulley 74 and formed over the entire circumference of the guide pulley 74.

[0036] As shown in FIG. 6 (see arrow), when the air in the chamber body 61 is sucked through the suction pipe 62, the air is sucked through each suction hole 21g located on the upper and lower surfaces of the chamber body 61 in the conveyor belt 21a through each suction groove 61b and each through hole 61d (see FIG. 4) of the chamber body 61. As a result, a suction force is applied to the tablet T on each suction hole 21g located on the upper and lower surfaces of the chamber body 61 in the conveyor belt 21a. In addition, the internal space of the chamber body 61 and the internal space of the pulley body 21b are communicated with each other through a slit-shaped through hole 70a. Therefore, when the air in the chamber body 61 is sucked through the suction pipe 62 as described above, the chamber body 61 sucks air from the internal space of the pulley body 21b through the slit-shaped through hole 70a, and the conveyor belt 21a is sucked through the suction groove 73a, and air is sucked through each suction hole 21g located on the outer periphery of the pulley body 21b in the conveyor belt 21a. As a result, a suction force is applied (acts) to the tablets T above the suction holes 21g located on the outer periphery of the pulley body 21b of the conveyor belt 21a.

[0037] Here, the above-mentioned suction force is required to be more than the suction force that resists the weight of the tablet T and the centrifugal force generated during transportation. In detail, at least the suction force (relatively weak suction force) that does not cause the tablet T to shift or shake during transportation is required in the upper surface region of the conveyor belt 21a. In the lower surface region of the conveyor belt 21a, a suction force that does not cause the tablet T to fall is required, and further, in the region of the conveyor belt 21a where the pulley body 21b rotates in the circumferential direction, a suction force that resists the centrifugal force is required. For this reason, the suction force acting on the tablet T on each suction hole 21g located on the outer periphery of the pulley body 21b of the conveyor belt 21a becomes strong. The surface of the conveyor belt 21a in this portion may bend due to the suction force, and if the surface of the conveyor belt 21a becomes uneven as a result, stable transportation of the tablet T becomes difficult. In order to prevent this, a pair of guide pulleys 73 and 74 that support the conveyor belt 21a is provided. If the conveyor belt 21a has a high rigidity and the flatness of the surface of the conveyor belt 21a can be maintained, the pair of guide pulleys 73, 74 can be removed (see the third embodiment).

[0038] (Printing process) Next, the printing process and the inspection process performed by the above-mentioned tablet printing apparatus 1 will be described.

[0039] 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 put into 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 arranged in two rows by the alignment feeder 12 and moved. The tablets T moving in these two rows are sequentially supplied to the conveyor belt 21a by the transfer feeder 13. The conveyor belt 21a is rotated in the conveying direction A1 by the rotation of the pulley body 21b and each driven pulley 21c by the motor 21d. Therefore, the tablets T supplied onto the conveyor belt 21a are lined up in two rows on the conveyor belt 21a and conveyed at a predetermined moving speed. The conveyor belt 31a is also rotated in the conveying direction A2 by the rotation of the pulley body 31b and each driven pulley 31c by the motor 31d.

[0040] Thereafter, the tablet T on the conveyor belt 21a is detected by the detection device 22. As a result, the 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 above-mentioned position information of the tablet T, 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) 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, the 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.

[0041] Next, printing is performed on each tablet T on the conveyor belt 21a by the print head device 24 based on the above-mentioned printing conditions at a timing based on the position information of the tablet T described above, 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) are printed on the upper surface of the tablet T.

[0042] 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 each image 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 judges whether the printing on the tablet T is good or bad, and printing result information indicating the result of the printing on each tablet T is stored in the memory unit 54. For example, it is judged whether the printing pattern is printed at a predetermined position on the tablet T.

[0043] After the inspection, the tablet T is transported with the movement of the conveyor belt 21a and passes above the drying device 26. At this time, the ink applied to 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 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 the state held by the conveyor belt 21a and is passed from the first printing device 30 to the second printing device 30.

[0044] Thereafter, the second printing device 30 performs the printing process and the inspection process in the same manner as described above. The tablets T after the inspection are transported with the movement of the conveyor belt 31a and pass above the drying device 36. Then, the tablets T with the dried ink reach the defective product collecting device 41. The defective tablets T are dropped from the conveyor belt 31a by the gas sprayed from the spray nozzle 41a and collected by the storage unit 41b. On the other hand, the non-defective tablets T pass through the defective product collecting device 41 and reach the non-defective product collecting device 42. At this position, the suction action of the non-defective tablets T stops working on the tablets T, and the non-defective tablets T are separated from the conveyor belt 31a and dropped by the gas blown from the gas blowing unit 42a and collected by the storage unit 42b.

[0045] In such a printing process, the air in the chamber body 61 is sucked through the suction pipe 62, and the air in the pulley body 21b is sucked through the slit-shaped through hole 70a extending in the rotation direction of the pulley body 21b by the chamber body 61. As a result, a suction force acts on the tablets T on each suction hole 21g located on the outer periphery of the pulley body 21b in the conveyor belt 21a, so that the pulley body 21b functions as a chamber for sucking air from each suction hole 21g located on the outer periphery of the pulley body 21b in the conveyor belt 21a. In addition, each guide pulley 73, 74 of the pulley body 21b rotates together with the conveyor belt 21a. As a result, there is no relative movement between the guide pulleys 73, 74 constituting the chamber and the conveyor belt 21a, so that no frictional force that hinders the rotation of the conveyor belt 21a is generated in the pulley body 21b.

[0046] In this embodiment, the guide pulleys 73, 74 of the pulley body 21b are configured to rotate together with the conveyor belt 21a, so that the generation of frictional force that impedes the rotation of the conveyor belt 21a can be prevented at least in the conveyor belt portion stretched over the pulley body 21b. This reduces the load fluctuation on the driving unit 21d such as a motor, so that it is possible to suppress the vibration of the conveyor belt 21a, and the conveyor belt 21a can stably convey the tablets T. As a result, it is possible to prevent a decrease in print quality (print misalignment, blurring, etc.) and the dropping of tablets T due to the vibration of the conveyor belt 21a.

[0047] As described above, according to the first embodiment, the internal space of the chamber body 61 and the internal space of the pulley body 21b communicate with each other through the slit-shaped through hole 70a, and when the air in the chamber body 61 is sucked through the suction pipe 62, the chamber body 61 sucks air from the internal space of the pulley body 21b through the slit-shaped through hole 70a. As a result, a suction force acts on the tablets T on each suction hole 21g located on the outer periphery of the pulley body 21b in the conveyor belt 21a. Therefore, the pulley body 21b functions as a chamber for sucking air from each suction hole 21g located on the outer periphery of the pulley body 21b in the conveyor belt 21a. Furthermore, since the pair of guide pulleys 73 and 74 of the pulley body 21b rotate together with the conveyor belt 21a, the force resisting the movement of the conveyor belt 21a is suppressed, and the conveyor belt 21a moves smoothly. As a result, it is possible to suppress the vibration of the conveyor belt 21a, so that the conveyor belt 21a can stably convey the tablets T. In addition, the internal space of the rotating pulley body 21b and the internal space of the fixedly disposed chamber main body 61 communicate with each other via the slit-shaped through hole 70a, and since there is no sliding part between them, the generation of dust, which is a major enemy in tablet printing devices, can be prevented. In addition, the air inside the pulley body 21b can be sucked through the suction pipe 62 connected to the chamber main body 61, so that the device configuration can be prevented from becoming complicated.

[0048] Furthermore, compared to the conventional suction chamber, since the pulley body 21b and the chamber body 61 can be removed separately from the tablet printing apparatus 1, when cleaning the suction chamber, the pulley body 21b and the chamber body 61 can be cleaned separately. This makes it possible to lighten the members to be cleaned at one time, allowing the operator to easily carry each member, and facilitating the cleaning work.

[0049] 4, guide portions 61a are provided on the upper and lower surfaces of the chamber body 61, and multiple grooves 61c are formed in the guide portions 61a. The conveyor belt 21a moves relative to the upper and lower surfaces of the chamber body 61, but by forming the grooves 61c, the contact area between the chamber body 61 and the conveyor belt 21a is reduced, and this makes it possible to further reduce the load fluctuation of the drive portion 21d associated with the movement of the conveyor belt 21a.

[0050] In the tablet printing device 1, a large number of tablets T, for example, tablets obtained by compressing powder or granular powder, are sequentially conveyed by the conveyor belt 21a, so that the powder of the tablets T gradually accumulates on the conveyor belt 21a. The powder of the tablets T may enter and adhere to the suction grooves 73a, 74a and the through holes 73c, 74c of the pulley body 21b from the through holes 21g. This causes a decrease in the suction force for sucking the tablets T. However, since the outer peripheral surface of the pulley body 21b is not covered by the conveyor belt 21a on the chamber main body 61 side and is exposed to the opening of the chamber main body 61, the powder of the tablets T adhering to the suction grooves 73a, 74a and the through holes 73c, 74c of the pulley body 21b is sucked in from the opening of the chamber main body 61 (see arrow a2 in FIG. 6). This makes it possible to remove the powder of the tablets T adhering to the suction grooves 73a, 74a and the through holes 73c, 74c of the pulley body 21b, and prevents a decrease in the suction force for sucking the tablets T due to the powder of the tablets T, thereby realizing stable transportation of the tablets T. In addition, the number of times maintenance for cleaning the pulley body 21b can be reduced, or such maintenance can be eliminated. Note that a filter (not shown) may be provided midway through the suction pipe 62 to capture the powder of the tablets T.

[0051] <Second embodiment> The second embodiment will be described with reference to Figures 7 and 8. Note that in the second embodiment, differences from the first embodiment (the configuration of the pulley body) will be described, and other descriptions will be omitted.

[0052] As shown in Fig. 7 and Fig. 8, a pulley body 80 according to the second embodiment is a pulley body having an internal space. The pulley body 80 has a pair of conveying pulleys 81, 82 and one guide pulley 83. The pair of conveying pulleys 81, 82 have the same structure as the pair of conveying pulleys 71, 72 according to the first embodiment, and therefore the description thereof will be omitted. Note that the conveying belt 21a is omitted in Fig. 7.

[0053] The guide pulley 83 is formed in a cylindrical shape. At both ends of the guide pulley 83, suction grooves 83a and grooves 83b are formed around the entire circumference of the guide pulley 83 so as to extend in the rotation direction of the guide pulley 83. The suction grooves 83a are formed at positions facing the rows of suction holes 21g of the conveyor belt 21a hung on the pulley body 80. At the bottom surface of the suction grooves 83a, a plurality of through holes 83c are arranged in the rotation direction of the guide pulley 83 and are formed around the entire circumference of the guide pulley 83. The diameter of these through holes 83c is, for example, about several millimeters. At the center of the guide pulley 83, a plurality of through holes 80a are arranged in the rotation direction of the guide pulley 83 and are formed around the entire circumference of the guide pulley 83. As a result, the guide pulley 83 has a plurality of through holes 80a arranged in the rotation direction. The diameter of each through hole 80a is, for example, about several centimeters, which is larger than the diameter of the through holes 83c. The internal space of the pulley body 80 and the internal space of the chamber main body 61 communicate with each other via these through holes 80a.

[0054] According to such a pulley body 80, the internal space of the pulley body 80 and the internal space of the chamber body 61 communicate with each other through holes 80a, and when air in the chamber body 61 is sucked through the suction pipe 62, air is sucked from the internal space of the pulley body 80 by the chamber body 61 through each through hole 80a. As a result, a suction force acts on the tablets T on each suction hole 21g located on the outer periphery of the pulley body 80 on the conveyor belt 21a, so that the pulley body 80 functions as a chamber for sucking air from each suction hole 21g located on the outer periphery of the pulley body 80 on the conveyor belt 21a.

[0055] In addition, the guide pulley 83 of the pulley body 80 rotates together with the conveyor belt 21a. This reduces the force resisting the movement of the conveyor belt 21a, allowing the conveyor belt 21a to move smoothly and reducing the motor load. This makes it possible to suppress the vibration of the conveyor belt 21a, allowing the conveyor belt 21a to stably convey the tablets T. As a result, it is possible to prevent deterioration of print quality and dropping of tablets T caused by vibration of the conveyor belt 21a.

[0056] As described above, according to the second embodiment, it is possible to obtain the same effects as those of the first embodiment. In addition, the pair of guide pulleys 73, 74 can be integrated into a single component of the guide pulley 83, which makes it easier to assemble the pulley body 80.

[0057] <Third embodiment> The third embodiment will be described with reference to Fig. 9. Note that in the third embodiment, differences from the first embodiment (the configuration of the pulley body) will be described, and other descriptions will be omitted.

[0058] 9, a pulley body 90 according to the third embodiment is a pulley body having an internal space. This pulley body 90 does not have the pair of guide pulleys 73, 74 according to the first embodiment, but has a pair of conveying pulleys 91, 92. These conveying pulleys 91, 92 have basically the same structure as the pair of conveying pulleys 71, 72 according to the first embodiment, so differences therebetween will be described.

[0059] The pair of conveying pulleys 91, 92 are provided facing each other at a distance in the extending direction of the rotating shaft 21h of the motor 21d. As a result, the pulley body 90 has an internal space 90a which is a gap between the pair of conveying pulleys 91, 92. The width of the internal space 90a is a width formed by the conveying pulleys 91, 92 holding the width direction ends of the conveying belt 21a, and is about several centimeters to several tens of centimeters. The internal space 90a of the pulley body 90 and the internal space of the chamber main body 61 communicate with each other through an opening at the end of the chamber main body 61 on the pulley body 90 side.

[0060] According to such a pulley body 90, the internal space of the pulley body 90 and the internal space of the chamber body 61 are communicated by the opening of the chamber body 61 and the internal space 90a of the pulley body 90, and when the air in the chamber body 61 is sucked through the suction pipe 62, the air is sucked from the internal space 90a of the pulley body 90 by the chamber body 61. As a result, a suction force acts on the tablet T on the suction hole 21g located on the outer periphery of the pulley body 90 in the conveyor belt 21a, so that the pulley body 90 functions as a chamber for sucking air from each suction hole 21g located on the outer periphery of the pulley body 90 in the conveyor belt 21a. This pulley body 90 is configured so that the chamber is completed by hanging the conveyor belt 21a on the pulley body 90.

[0061] Furthermore, the pulley body 90 does not have a guide, and the pair of conveying pulleys 91, 92 rotate together with the conveying belt 21a. This reduces the force resisting the movement of the conveying belt 21a, so that the conveying belt 21a moves smoothly and also reduces the motor load. This makes it possible to suppress the vibration of the conveying belt 21a, and the conveying belt 21a can stably convey the tablets T. As a result, it is possible to prevent a deterioration in print quality and the tablets T from falling due to the vibration of the conveying belt 21a.

[0062] As described above, according to the third embodiment, as in the first embodiment, it is possible to suppress vibration of the conveyor belt 21a, so that the conveyor belt 21a can stably convey the tablets T. In addition, it is possible to eliminate the need for the pair of guide pulleys 73, 74, and the configuration of the pulley body 90 can be simplified.

[0063] <Fourth embodiment> The fourth embodiment will be described with reference to Fig. 10. Note that in the fourth embodiment, only the difference from the first embodiment (the suction force adjusting means) will be described, and other descriptions will be omitted.

[0064] In the fourth embodiment, in order to reduce the suction force applied to the tablets T in a first region on the conveyor belt 21a where printing processing is performed to be lower than the suction force applied to the tablets T in a second region other than the first region, the suction chamber (chamber 21f and pulley body 21b) is divided into multiple sections, and the suction force is adjusted for each section. This suction force adjustment means functions as a suction force adjustment device. The first region is a predetermined region that includes at least the region below the print head device 24 on the conveyor belt 21a, and the second region is a region on the conveyor belt 21a where the tablets T are suction-transported, other than the first region.

[0065] As shown in FIG. 10, partition walls 63 and 64 are formed in two places inside the chamber body 61, and the lower ends of the partition walls 63 and 64 are connected by a floor material 65 to provide one room. This divides the inside of the chamber body 61 into two sections B1 and B2. The partition wall 63 is formed at the position of reference symbol b1 shown in FIG. 10, and the partition wall 64 is formed at the position of reference symbol b2 shown in FIG. 10. That is, the inside of the chamber body 61 is divided by the partition walls 63 and 64 and the floor material 65 into a first section B1 formed between the positions of reference symbols b1 and b2, and a second section B2 which is the other section. A suction pipe 62a is connected to the first section B1, and a suction pipe 62b is connected to the second section B2.

[0066] The two compartments B1, B2 are separated by partitions 63, 64 and a floor material 65, and suction pipes 62a, 62b are provided separately, so that air does not pass between them. This makes it possible to set different suction forces (suction pressure, suction air volume, and suction air speed) for each of the compartments B1, B2 and suck air. For example, the suction force applied to the tablets T in the first compartment B1 is set to be weaker than the suction force applied to the tablets T in the second compartment B2.

[0067] Here, the tablet T on the conveyor belt 21a in the chamber 21f is sucked and held on the conveyor belt 21a by the chamber 21f sucking air through the suction hole 21g. That is, the tablet T is sucked and held in the suction hole 21g of the conveyor belt 21a by the suction force of the chamber 21f. At this time, the suction hole 21g may or may not be blocked by the tablet T being sucked and held. This is because the tablet T may not completely block the suction hole 21g depending not only on the presence or absence of the tablet T being sucked and held, but also on the size, shape, or posture of the tablet T. If the tablet T cannot completely block the suction hole 21g, a space is created in which air is sucked from the suction hole 21g toward the chamber 21f near the contact position between the suction hole 21g and the tablet T. In such a case, as the tablet T is sucked and held through the suction hole 21g, the air present in the vicinity of the tablet T is sucked through the upper and side surfaces of the tablet T and the suction hole 21g. In particular, when the suction force of the chamber 21g is strong, the amount of sucked air increases and the flow rate of the sucked air increases, which may result in a stronger airflow near the tablet T, a larger range of the airflow, or turbulence in the airflow.

[0068] The print head device 24 that prints on the tablets T includes an inkjet print head 24a (see FIG. 2). In the case of the inkjet method, ink is ejected from the print head 24a toward the tablet T to be printed, and printing is performed by landing on the surface of the tablet T. From the time when the ink is ejected from the print head 24a until it lands on the surface of the tablet T, the ink is in a state of flying between the print head 24a and the tablet T. At this time, if an airflow occurs in the space between the print head 24a and the tablet T, the shape of the ink ejected from the print head 24a during flight may be distorted by the airflow, or the flying direction may be affected by the airflow and the landing position may be shifted, resulting in poor printing and a decrease in print quality. It is fine if the airflow does not affect the print quality, but if the airflow is strong, the reach of the airflow is large, or the airflow is turbulent, the print quality will be significantly reduced. Furthermore, if the influence of the air flow reaches the vicinity of the nozzle that ejects the ink of the print head 24a, the ink near the nozzle will dry out, causing ejection failure and also resulting in a decrease in print quality. Alternatively, it is possible that the ink that does not land on the tablet T will scatter in a mist. If the ink scatters in a mist, for example, it will be sucked in together with the air sucked in by the chamber 21f, causing adhesion to the side of the tablet T being transported, etc.

[0069] Therefore, in the fourth embodiment, the suction force applied to the tablet T during printing is weakened to reduce the amount and flow rate of the sucked air, thereby minimizing the occurrence of printing defects due to airflow or mist. That is, at least when the tablet T passes under the print head device 24 to perform the printing process, the suction force applied to this tablet T is reduced below the suction force applied to tablets T at other positions on the conveyor belt 21a. Note that this reduced suction force is determined in advance by experiments, etc., taking into consideration printing defects and conveyance deviations due to airflow and mist.

[0070] Here, if the above-mentioned suction force adjustment means is applied to a normal suction chamber (where the pulley does not constitute part of the suction chamber), the suction force in the first region will be lower than the suction force in the second region, and there is a possibility that the tablets T on the conveyor belt 21a will not be adequately attracted and held in the printing area below the print head device 24. This makes the tablets T more likely to oscillate due to vibrations from the conveyor device. If the tablets T are not adequately held and oscillate, the printing on the tablets T may become distorted and double, resulting in printing defects.

[0071] Therefore, according to the fourth embodiment, by applying the above-mentioned suction force adjustment means to the suction chamber (the pulley constitutes a part of the suction chamber) according to the first embodiment, it is possible to suppress the vibration of the conveyor belt 21a as in the first embodiment while suppressing the deterioration of print quality caused by the air flow as described above, so that the conveyor belt 21a can stably convey the tablets T. As a result, it is possible to sufficiently adsorb and hold the tablets T even in the printing area below the print head device 24 and suppress the shaking of the tablets T, so that the deterioration of print quality caused by the shaking of the tablets T can be suppressed.

[0072] In addition, the suction force may be reduced not only when the tablet T passes under the print head device 24, but also, for example, from a predetermined position (position of reference symbol b1) upstream of the print head device 24 until the tablet T passes under the print head device 24 and reaches a predetermined position (position of reference symbol b2) downstream of the print head device 24. That is, on the upstream side of the print head device 24, the suction force may be reduced before the tablet T passes under the first imaging device 23 that detects the position and posture of the tablet T on the conveyor belt 21a after being supplied to the conveyor belt 21a. Also, on the downstream side of the print head device 24, the suction force may be reduced until the tablet T passes under the second imaging device 25 that detects the position and posture of the tablet T on the conveyor belt 21a after being printed by the print head device 24.

[0073] This is because the first imaging device 23 detects the position and posture of the tablet T that is about to enter the printing process, or the second imaging device 25 detects the printing position (printing state) of the printing pattern of the printed tablet T, so it is necessary to detect the position and posture of the tablet T that is sucked in the same state as during the printing process, that is, the printing state of the tablet T in a state where the suction force is reduced. For example, if a change in the suction force occurs during the transportation of the tablet T and this change is large, the tablet T may shift or shake, changing its position or posture. If the position or posture of the tablet T changes due to such a large change in suction force between the detection of the position or posture of the tablet T by the first imaging device 23 and the end of the printing process, proper printing may not be performed. Alternatively, if the position or posture of the tablet T changes between the end of the printing process and the detection of the printing state of the tablet T by the second imaging device 25, proper inspection may not be performed. Therefore, it is preferable to prevent a large change in suction force from the time when the position, posture, etc. of the tablet T is detected by the first imaging device 23 until the printing process is completed, or from the time when the printing process is completed and the printing state of the tablet T is detected by the second imaging device 25, so that the detected position and posture state of the tablet T do not change. Furthermore, it is also possible to prevent a large change in suction force from the first imaging device 23 to the second imaging device 25. In this way, the position and posture of the tablet T or the printing state of the tablet T can be detected in a state where the suction force applied to the tablet T is reduced to the same level as during the printing process.

[0074] Here, the first region is the region where the tablet T is sucked and held by the conveyor belt 21a with the reduced suction force among the regions where the tablet T is conveyed by the conveyor belt 21a. Therefore, based on the above example, the region from a predetermined position (position of symbol b1) before the tablet T passes under the first imaging device 23 after being supplied to the conveyor belt 21a to a predetermined position (position of symbol b2) after the tablet T passes under the print head device 24 and passes under the second imaging device 25 corresponds to the first region. In other words, the first region includes a region from the imaging position of the tablet T by the first imaging device 23 to the imaging position of the tablet T by the second imaging device 25 on the conveyor belt 21a. Note that, although suction force is applied to the suction holes 21g over the entire circumference of the conveyor belt 21a, for the second region other than the first region, it is not necessary to consider the effect on the ink flying during printing, so it is not necessary to particularly reduce the suction force, and it is sufficient to set the suction force to be greater than or equal to the centrifugal force and weight generated during conveyance.

[0075] (Modification) In the above explanation, it is assumed that the suction chamber (chamber 21f and pulley body 21b) is divided into two sections B1 and B2 and two types of suction force are applied. However, the suction force applied to the tablets T is not limited to two types and may be controlled for each process performed in the tablet printing device 1. Therefore, in this case, two or more types of suction force are appropriately applied to the tablets T.

[0076] For example, the suction chamber is divided into three sections (upper and lower sections in chamber 21f, and a section in pulley body 21b), and the upper section in chamber 21f is configured to receive a suction force that prevents tablets T from shifting or shaking during transport and does not affect the printing process, the lower section is configured to receive a suction force that prevents tablets T from falling, and the section in pulley body 21b, i.e., the section in which tablets T move in the circumferential direction on pulley body 21b, is configured to receive a suction force that prevents tablets T from falling and resists centrifugal force. This allows tablets T to be more appropriately suctioned and held on the conveyor belt 21a. In such a lower section in chamber 21f and a section in pulley body 21b, a suction force significantly greater than the suction force in the upper section in chamber 21f is required, but an optimal suction force can be appropriately applied to tablets T in each process (position to which tablets T are transported). In other words, in the conveyor belt 21a, the region where the suction force is weakened corresponding to the upper section in the chamber 21f as described above is the first region, and the other regions corresponding to the lower section and the section in the pulley body 21b are the second region. The suction force in the lower section in the chamber 21f and the section in the pulley body 21b can be changed, but is made stronger than the suction force in the upper section in the chamber 21f.

[0077] As described above, in a state where an air current caused by suction is generated around the tablet T on the conveyor belt 21a, the suction force is reduced so that the tablet T is reliably sucked and held anywhere on the conveyor belt 21a, but the air current is weak enough during printing to prevent printing defects. Since the printing process is performed in the upper region of the conveyor belt 21a between the pulley body 21b and each driven pulley 21c, the tablet T is supported by the conveyor belt 21a, and even if the suction force in the upper region is reduced compared to other regions, it does not affect transportation.

[0078] Furthermore, when the tablets are transferred from the supply device 10 to the conveying device 21, or from the conveying device 21 to the conveying device 31, the tablets T after being transferred will sway. If there is such a sway, i.e., if the tablets T sway, it will be impossible to detect or print their positions accurately. Therefore, it is better for the suction force near the position on the side where the tablets are transferred to be large. The larger the suction force, the faster the tablet T's swaying can be converged. In other words, in the chamber 21f of the conveying device 21, or in the compartment above the chamber 31f of the conveying device 31, a further compartment may be provided in the portion where the transfer process is performed, and the suction force of that compartment may be set to a suction force that quickly converges the swaying of the tablets T.

[0079] As described above, it is possible to provide as many compartments as necessary in the necessary parts. That is, it is possible to partition the suction chamber into a first region and a second region, and further partition the region. Then, the suction force can be set appropriately for each compartment. In addition, at the joints between the compartments with different suction forces, the suction force changes. If such a change is large, the tablet T may shift, shake, or fall off the belt. Therefore, it is possible to provide compartments before and after the compartment with the required suction force to make the change in the suction force gentle. In this way, it is possible to make the change in the suction force gentle across the compartments, and it is possible to suppress the tablet T from shifting, shaking, or falling off the belt.

[0080] <Fifth embodiment> Next, a fifth embodiment will be described with reference to Fig. 11 to Fig. 13. Note that in the fifth embodiment, only the difference from the fourth embodiment (the attraction force reducing member) will be described, and other descriptions will be omitted.

[0081] In the above-mentioned fourth embodiment, in order to reduce the suction force applied to the tablets T in the first region where the printing process is performed on the conveyor belt 21a to be lower than the suction force applied to the tablets T in the other second region, the suction chamber (chamber 21f and pulley body 21b) is divided into a plurality of sections, and the suction force is changed for each section. On the other hand, in the fifth embodiment, in order to reduce the suction force applied to the tablets T in the first region to be lower than that in the second region without dividing the suction chamber into a plurality of sections, a suction force reducing member 66 (see Figs. 11 and 12) is used. This suction force reducing member 66 functions as a suction force adjusting device.

[0082] The suction force generated by the suction chamber is, for example, a suction force generated in a suction groove 61b (see FIG. 12) provided in the chamber body 61 by discharging the air in the suction chamber, and is determined by the speed and amount of air discharge. The suction force generated in the suction groove 61b acts on the tablet T through the suction holes 21g of the conveyor belt 21a, drawing the tablet T onto the conveyor belt 21a. This drawing force becomes the suction force for the tablet T. Therefore, in the fifth embodiment, the suction force acting on the tablet T on the conveyor belt 21a is reduced by the suction force reduction member 66, without changing the speed and amount of air discharged from the chamber body 61.

[0083] 11, a suction force reducing member 66 is provided in a first region (a range from the position of symbol b1 to the position of symbol b2) of the conveyor belt 21a. This suction force reducing member 66 is provided for each conveying path of the tablet T, i.e., for each suction groove 61b.

[0084] As shown in Fig. 12, the suction force reducing member 66 is detachably attached to the bottom surface of the suction groove 61b. The suction force reducing member 66 is formed, for example, in a triangular shape so that the opening area of ​​each through hole 61d aligned in the conveying direction A1 gradually decreases along the conveying direction A1. As a result, the suction force on the tablet T in the first region gradually decreases along the conveying direction A1.

[0085] In addition, because the suction reduction member 66 is detachable, the user can reduce the suction force in a desired pattern in a desired area by shifting the suction reduction member 66 in the transport direction A1 or by replacing it as necessary. In other words, the suction force or the position where the suction force is reduced can be easily adjusted, and maintenance can be easily performed by removing the suction reduction member 66 and cleaning it.

[0086] As described above, by providing the suction force reducing member 66 in the first region of the conveyor belt 21a, the suction force of the suction holes 21g in the first region is weakened, and the amount and flow speed of air sucked through the suction holes 21g are reduced, making it possible to prevent printing defects caused by airflow and mist from occurring. That is, the suction force that sucks in at least the tablets T passing below the print head device 24 (the region of the conveyor belt 21a from below the upstream end of the print head device 24 to below the downstream end) can be made lower than the suction force that sucks in tablets T at other positions on the conveyor belt 21a.

[0087] Furthermore, by gradually decreasing the suction force in the first region of the conveyor belt 21a, it is possible to suppress the displacement of the tablet T due to a sudden decrease in the suction force. For example, if the suction force changes suddenly, the tablet T may shift, shake, or fall off the conveyor belt 21, but by making the change in the suction force gentle, it is possible to suppress the occurrence of such problems.

[0088] Here, if the above-mentioned suction force reduction member 66 is applied to a normal suction chamber (in which the pulley does not form part of the suction chamber), the conveying belt 21a will oscillate with the suction force reduced, similar to the concerns mentioned in the fourth embodiment above. If the tablet T oscillates without being sufficiently held, the printing on the tablet T will become distorted and double, which may result in poor printing.

[0089] Therefore, according to the fifth embodiment, by applying the above-mentioned suction force reducing member 66 to the suction chamber (the pulley constitutes a part of the suction chamber) according to the first embodiment, it is possible to suppress the vibration of the conveyor belt 21a as in the first embodiment while suppressing the deterioration of print quality caused by the air flow as described above, so that the conveyor belt 21a can stably convey the tablets T. As a result, it is possible to sufficiently adsorb and hold the tablets T even in the printing area below the print head device 24 and suppress the shaking of the tablets T, so that the deterioration of print quality caused by the shaking of the tablets T can be suppressed.

[0090] FIG. 13 shows a comparison of the motor load factor, chamber pressure, vibration of the transport belt, and print quality between a case in which the suction force reducing member 66 is applied to a normal chamber and this embodiment (fifth embodiment).

[0091] For example, as shown in FIG. 13, in the normal suction chamber, the motor load rate is 98%, the chamber pressure is -1.9 kPa, the vibration of the conveyor belt 21a is large, and there is blurring (printing defect). On the other hand, in the suction chamber according to the fifth embodiment, the motor load rate is 37%, the chamber pressure is -1.9 kPa, the vibration of the conveyor belt 21a is small, and there is no blurring (printing defect). Therefore, in the suction chamber according to the fifth embodiment, even though the chamber pressure is the same as that of the normal suction chamber, the motor load rate is smaller and the vibration of the conveyor belt 21a is also smaller than that of the normal suction chamber, and there is no blurring. In this way, the pressure in the suction chamber is kept the same in both suction chambers, but it is clear that the motor load rate is significantly reduced, the vibration is reduced, and the blurring is suppressed according to the suction chamber according to the fifth embodiment.

[0092] The suction force reducing member 66 may be provided at any position within the suction groove 61b as long as it is a position where it can avoid contact with the conveyor belt 21a. Also, the suction force reducing member 66 may be provided anywhere other than the suction groove 61b itself as long as it can limit the amount of air passing through in order to reduce the suction force acting on the tablet T via the conveyor belt 21a, or a separate member may be provided.

[0093] (Modification) In the above description, one type of suction force reducing member 66 has been described. As the suction force reducing member 66, it is also possible to use other members capable of generating the same effect as the suction force reducing member 66, such as a brim-shaped member or a plate-shaped member. The type of suction force to be applied to the tablet T can be freely set by the shape and number of the brim-shaped member or plate-shaped member, and the size, shape, and number of the openings formed in the plate-shaped member.

[0094] The suction force reducing member 66 may be any shape that gradually changes the opening area of ​​the through holes 61d arranged in a row, and may be a punching board, a net-like member, a porous member, or the like. In this case, the density of the holes is reduced so that the opening area of ​​the through holes 61d gradually decreases along the conveying direction A1. In addition, by overlapping the punching board or net-like member and shifting them relatively, the size and opening rate of the openings of the holes formed in the punching board, and the size and opening rate of the mesh of the net, can be changed to adjust the suction force applied to the tablet T passing through the first region.

[0095] It should be noted that, without providing the above-mentioned suction force reducing member 66, for example, the suction force may be reduced by reducing the size of the through hole 61d, and various suction force adjusting means (suction force adjusting devices) can be used.

[0096] Sixth embodiment Next, a sixth embodiment will be described with reference to Fig. 14. Note that in the sixth embodiment, only the difference from the fifth embodiment (the suction chamber) will be described, and other descriptions will be omitted.

[0097] 14, the chamber 21f and the pulley body 21b according to the sixth embodiment form a suction chamber as in the first embodiment, but the internal space of the chamber 21f is not connected to the internal space of the pulley body 21b. That is, the opening of the chamber 21f on the pulley body 21b side is closed, and the opening of the slit-shaped through hole 70a in the pulley body 21b is also closed, so that the internal space of the chamber 21f does not communicate with the internal space of the pulley body 21b.

[0098] The pulley body 21b is connected to a rotating shaft 21h, and the rotating shaft 21 passes through the internal space of the pulley body 21b. The rotating shaft 21h is formed hollow, and a plurality of through holes (not shown) arranged in the circumferential direction are formed on the outer periphery of the rotating shaft 21h. These through holes allow the internal space of the rotating shaft 21h to communicate with the internal space of the pulley body 21b. The rotating shaft 21h is connected to a suction pipe (neither shown) via a connecting member such as a rotary joint, and the suction pipe is connected to a suction device (not shown) such as a pump.

[0099] In this configuration, the air in the chamber body 61 is sucked through the suction pipe 62. As a result, a suction force acts on the tablets T on each suction hole 21g located on the outer periphery of the chamber body 61 in the conveyor belt 21a. Meanwhile, the air in the pulley body 21b is sucked through the rotating shaft 21h and the suction pipe, and flows through the inside of the rotating shaft 21h and the inside of the suction pipe. As a result, a suction force acts on the tablets T on each suction hole 21g located on the outer periphery of the pulley body 21b in the conveyor belt 21a. This pulley body 21b rotates together with the conveyor belt 21a.

[0100] In this configuration, as in the fourth and fifth embodiments described above, it is possible to suppress the vibration of the conveyor belt 21a while suppressing the deterioration of print quality caused by airflow, so that the conveyor belt 21a can stably convey the tablets T. This makes it possible to sufficiently adsorb and hold the tablets T in the printing area below the print head device 24 and suppress the shaking of the tablets T, so that the deterioration of print quality caused by the shaking of the tablets T can be suppressed.

[0101] <Seventh embodiment> Next, a seventh embodiment will be described with reference to Fig. 15 to Fig. 21. In the seventh embodiment, differences from the first embodiment (the cover, the gas blowing unit, and the gas suction unit) will be described, and other descriptions will be omitted.

[0102] As shown in FIG. 15 and FIG. 16, in the seventh embodiment, a cover 100, two gas blowing units 200, and two gas suction units 300 are provided. Each gas blowing unit 200 and each gas suction unit 300 functions as an adhesion removal mechanism. This adhesion removal mechanism blows gas (e.g., air or inert gas) onto adhesions (e.g., powder or dirt) attached to the tablet T or the underside of the cover 100 on the conveyor belt 21a, blows off the adhesions from the underside of the tablet T or the cover 100, and sucks up the blown-off adhesions together with the air, thereby removing the adhesions from the underside of the tablet T or the cover 100. In addition, when the tablet T is conveyed by the conveyor belt 21a, the powder of the tablet T may fly in the device, and the powder flying in the device, especially the powder flying near the cover 100, is also removed by the gas blowing unit 200 and the gas suction unit 300.

[0103] 15, the cover 100 is a housing that houses the gas blowing unit 200, the detection device 22, the first imaging device 23, the print head device 24, and the second imaging device 25. The cover 100 is provided above the conveyor belt 21a with its lower surface spaced a predetermined distance (for example, 4 to 5 mm) from the upper surface of the conveyor belt 21a.

[0104] A plurality of through holes 100a are formed on the lower surface of the cover 100 so that each gas blowing section 200 in the cover 100 can blow gas onto the upper surface of the conveyor belt 21a. These through holes 100a are formed, for example, so as to be aligned in a line in the conveying direction A1 of the tablets T for each gas blowing section 200. The gas blown out from the gas blowing section 200 passes through each through hole 100a penetrating the lower surface of the cover 100, and is blown onto the conveyor belt 21a. For example, the diameter of the through hole 100a is several mm (for example, about 2 mm).

[0105] In addition, on the lower surface of the cover 100, two through holes 100b are formed in a direction perpendicular to the conveying direction A1 of the tablets T in a horizontal plane so that the detection device 22 (two detection units 22a) in the cover 100 can detect the tablets T on the conveyor belt 21a, and two through holes 100c are formed in a direction parallel to the direction in which the through holes 100b are arranged so that the first imaging device 23 (two imaging units 23a) in the cover 100 can image the tablets T on the conveyor belt 21a. Furthermore, on the lower surface of the cover 100, one through hole 100d is formed so that the print head device 24 in the cover 100 can print on the tablets T on the conveyor belt 21a, and two through holes 100e are formed in a direction parallel to the direction in which the through holes 100b are arranged so that the second imaging device 25 (two imaging units 25a) in the cover 100 can image the tablets T on the conveyor belt 21a.

[0106] Each through-hole 100a is covered by a gas blowing unit 200 provided on the bottom surface inside the cover 100, and each through-hole 100b, 100c, 100e is blocked by light-transmitting members 101, 102 such as glass provided on the bottom surface inside the cover 100. Furthermore, the through-hole 100d is blocked by inserting the print head device 24 into the through-hole 100d via a sealing member 103 such as silicone. In this way, the cover 100 is formed in a sealed state, and the inside of the cover 100 is maintained at a positive pressure.

[0107] Each gas blowing section 200 is connected to each through hole 100a on the lower surface of the cover 100, and blows gas from the through holes 100a onto the conveyor belt 21a. As a result, when the tablets T on the conveyor belt 21a pass under the gas blowing section 200, the gas is blown onto the tablets T on the conveyor belt 21a, and any adhering matter attached to the tablets T is blown off from the tablets T. Each gas blowing section 200 is connected to a gas supply section via a flow rate adjustment valve (none of which are shown), and gas is supplied to each gas blowing section 200 from the gas supply section.

[0108] Here, on the underside of the cover 100, the guide plate 104 is positioned downstream of the gas blowing section 200 in the conveying direction A1 of the tablet T, and is provided for each gas blowing section 200. These guide plates 104 are formed in a rectangular shape, and their longitudinal direction is parallel to a direction perpendicular to the conveying direction A1 of the tablet T in a horizontal plane, and is tilted toward the print head device 24. Each guide plate 104 causes a part of the gas blown out from the gas blowing section 200 through each through hole 100a to flow toward the downstream side of the conveying direction A1 of the tablet T, and generates an air flow that flows in the conveying direction A1 of the tablet T along the underside of the cover 100. As a result, the gas is blown onto the adhesions attached to the underside of the cover 100, and the adhesions are blown off from the underside of the cover 100. Note that, one guide plate 104 is provided for each of the gas blowing sections 200 arranged in two rows, but this is not limited thereto, and only one guide plate may be provided as a shared member.

[0109] Furthermore, on the underside of the cover 100, a blocking plate 105 is positioned between the first imaging device 23 and the print head device 24 (at least upstream of the print head device 24 in the conveying direction A1 of the tablet T), and is provided corresponding to each gas blowing section 200. These blocking plates 105 are formed in a rectangular shape, and their longitudinal direction is parallel to a direction perpendicular to the conveying direction A1 of the tablet T in a horizontal plane, and are provided perpendicular to the underside of the cover 100. The blocking plate 105 is provided at a height position such that its longitudinal length can cover the area where the nozzle 24b of the print head device 24 is formed, and the blocking plate 105 does not come into contact with the tablet T conveyed below it. Each of these blocking plates 105 blocks the gas that is guided by the guide plate 104 and flows along the underside of the cover 100. This prevents the air flow flowing along the underside of the cover 100 from adversely affecting the printing of the print head device 24.

[0110] Incidentally, the blocking plate 105 is provided for each of the two rows of gas blowing parts 200, but this is not limited thereto, and only one may be provided as a common member. The blocking plate 105 may also be provided in the print head device 24. By being attached to the print head device 24 itself, when the type of tablet T to be printed is changed and the thickness of the tablet T changes, the height position of the printing head device 24 can be adjusted and the height position of the blocking plate 105 can be automatically adjusted at the same time. Therefore, there is no need to adjust only the height position of the blocking plate 105 according to the thickness of the tablet T, which is efficient.

[0111] Each gas suction part 300 is positioned adjacent to the side of the conveyor belt 21a so as to sandwich the conveyor belt 21a, and is attached to the chamber body 61. Each of these gas suction parts 300 has an intake port 301, an exhaust port 302, and an internal flow path 303 (see FIG. 16).

[0112] The intake port 301 and the exhaust port 302 are formed in a rectangular shape (slit shape) extending in the conveying direction A1 of the tablet T. The intake port 301 is an opening for sucking air from the space between the upper surface of the conveyor belt 21a and the lower surface of the cover 100, and is positioned on the conveyor belt 21a side in the gas suction section 300 and is provided at a position higher than the upper surface of the conveyor belt 21a. The opening of the intake port 301 is provided so that its end is located upstream of the blocking plate 105 in the conveying direction A1. This prevents the gas from the gas blowing section 200 from flowing to the print head device 24, preventing the nozzle 24b of the print head device 24 from drying out and causing discharge defects, and preventing the liquid discharged from the nozzle 24b from being affected by the air flow and changing the discharge direction. The exhaust port 302 is positioned on the conveyor belt 21a side in the gas suction section 300, is provided at a position lower than the conveyor belt 21a, and is connected to the inside of the chamber main body 61. The internal flow path 303 is formed inside the gas suction part 300 and is a flow path connecting the intake port 301 and the exhaust port 302 .

[0113] Here, when the inside of the chamber main body 61 is sucked in order to transport the tablet T, air is sucked in from the exhaust port 302 in each gas suction section 300. Then, air in the space between the upper surface of the conveyor belt 21a and the lower surface of the cover 100 is sucked in from the intake port 301 via the internal flow path 303 connected to the exhaust port 302. As a result, the deposits blown off by the gas blown by the gas blowing section 200 are sucked in from the intake port 301 together with the air.

[0114] In addition, by changing the length in the height direction of the intake port 301, it is possible to adjust the suction force of the gas suction unit 300. However, it is desirable that the length in the height direction of the intake port 301 is shorter than the height of the tablet T. Usually, the suction force for sucking air from the intake port 301 is not set to a suction force that sucks the tablet T from the intake port 301, but there is a concern that the tablet T may be sucked from the intake port 301 when the adjustment of the suction force is insufficient or when the type of tablet T (the size of the tablet T is different) is changed. For this reason, by making the length in the height direction of the intake port 301 shorter than the height of the tablet T, it is possible to prevent the tablet T from being sucked from the intake port 301. In addition, the length in the extension direction of the intake port 301 is appropriately set based on the suction range required to remove the adhesion attached to the tablet T on the conveyor belt 21a.

[0115] In addition, the amount of gas from the gas blowing section 200 and the suction force of the air from the intake port 301 are set so that the position of the tablet T (including the position of the tablet T in the X direction, Y direction, and θ direction, and the posture of the tablet T such as the inclination) does not change on the conveying belt 21a or the tablet T falls from the conveying belt 21a due to the gas from the gas blowing section 200 or the suction force of the air from the intake port 301.

[0116] In addition, the gas blowing from the gas blowing unit 200 and the air suction from the gas suction unit 300 are always performed during the operation of the tablet printing device 1. Even if the tablet T does not arrive at the gas blowing unit 200, the detection device 22, the first imaging device 23, or the print head device 24 for a certain period of time, the gas blowing from the gas blowing unit 200 and the air suction from the gas suction unit 300 can be performed to remove powder adhering to the conveyor belt 21a or prevent powder from adhering to the conveyor belt 21a. If powder of the tablet T adheres to the conveyor belt 21a, the powder is imaged by the first imaging device 23, and a false detection may occur even though the tablet T does not exist, resulting in printing on the conveyor belt 21a. However, by always blowing gas from the gas blowing unit 200 and suctioning air from the gas suction unit 300, such false detection can be prevented.

[0117] Furthermore, if new tablets T are supplied with powder adhering to the conveyor belt 21a, the tablets T may slip on the conveyor belt 21a, fall from the conveyor belt 21a, or change position on the conveyor belt 21a. By constantly blowing and sucking gas by the adhesion removal mechanism while the tablet printing device 1 is in operation, it is possible to prevent the tablets T from slipping on the conveyor belt 21a when the conveyance of the tablets T is resumed.

[0118] In the above-mentioned configuration, when printing the tablet T, the gas is blown onto the conveyor belt 21a from each through hole 100a by each gas blowing unit 200. Furthermore, the air in the chamber body 61 is sucked, and accordingly, the air in the space between the upper surface of the conveyor belt 21a and the lower surface of the cover 100 is sucked from the individual intake port 301 of each gas suction unit 300. In this state, when the tablet T being conveyed by the conveyor belt 21a passes under the gas blowing unit 200, the gas is blown onto the tablet T by the gas blowing unit 200. At this time, if any adhesion is attached to the tablet T, the adhesion is blown off from the tablet T, and the blown off adhesion is sucked together with the air by the gas suction unit 300. In this way, the adhesion attached to the tablet T is removed, so that it is possible to suppress printing on the tablet T with the adhesion attached, and the deterioration of the printing quality can be suppressed.

[0119] In addition, the gas is blown onto the conveyor belt 21a by the gas blowing unit 200, but a part of the gas is guided by the guide plate 104 to flow in the conveying direction A1 of the tablet T along the lower surface of the cover 100. As a result, the gas is blown onto the adhesions attached to the lower surface of the cover 100, and the adhesions are blown off from the lower surface of the cover 100. The blown off adhesions are sucked in by the gas suction unit 300 together with the air. In this way, the adhesions attached to the lower surface of the cover 100, i.e., the glass 101, are removed, so that it is possible to suppress detection abnormalities and recognition abnormalities, and it is possible to suppress a decrease in print quality. Furthermore, since the powder of the tablet T floating near the cover 100 can also be sucked in and removed, it is possible to suppress the adhesion of the powder of the tablet T to the tablet T, the lower surface of the cover 100, the conveyor belt 21a, etc. The longitudinal length, length along the conveying direction A1, and inclination angle of the guide plate 104 are set to a length and angle that allows the guide plate 104 to blow off any adhering matter adhering to the glass 101, and is provided so as not to come into contact with the tablets T conveyed below the guide plate 104. Also, the guide plate 104 is not limited to a flat plate, and may be a plate having a curved shape, as long as the guide plate 104 is capable of blowing off any adhering matter adhering to the glass 101.

[0120] As described above, a portion of the gas flows along the underside of the cover 100 due to the guide plate 104, but the gas flowing along the underside of the cover 100 in the conveying direction A1 of the tablet T is blocked by the blocking plate 105, and the blocked gas is sucked through the intake port 301 of the gas suction section 300. At this time, the deposits blown off from the underside of the cover 100 are also sucked through the intake port 301 together with the gas. This prevents the airflow flowing along the underside of the cover 100 and the deposits blown off from the underside of the cover 100 from adversely affecting the printing of the print head device 24, thereby preventing a decrease in print quality.

[0121] In addition, the above-mentioned conveyor belt 21a may vibrate due to rubbing against the upper and lower surfaces of the chamber main body 61 when conveying the tablets T. At this time, even if the conveyor belt 21a vibrates and the attached matter (for example, powder or dust) attached to the conveyor belt 21a tries to fly up, the flying up is suppressed by the gas blown from the gas blowing section 200, and even if the attached matter does fly up, the flying attached matter is sucked up by the gas suction section 300. This prevents the attached matter attached to the conveyor belt 21a from adhering to the tablets T on the conveyor belt 21a, so that a decrease in print quality can be suppressed.

[0122] In addition, the seventh embodiment can be applied to other embodiments, for example, the fourth and fifth embodiments described above. In these cases, the suction force of a part (first region) of the suction chamber 21f is reduced, and the conveyor belt 21a may vibrate at the reduced suction force portion. At this time, even if the conveyor belt 21a vibrates and the deposits attached to the conveyor belt 21a try to fly up, the lifting is suppressed by the gas blown from the gas blowing unit 200, and even if the deposits fly up, the lifted deposits are sucked up by the gas suction unit 300. This prevents the deposits attached to the conveyor belt 21a from adhering to the tablet T on the conveyor belt 21a, thereby suppressing the deterioration of print quality.

[0123] (Modification 1 and Modification 2 of Gas Suction Section) In the above description, the intake port 301 of the gas suction unit 300 is formed in a rectangular shape extending in the conveying direction A1 of the tablet T, but the present invention is not limited thereto. For example, as shown in FIG. 17, the intake port 301 may be formed in a triangular shape that gradually narrows along the conveying direction A1 of the tablet T (Modification 1), or as shown in FIG. 18, a plurality of rectangular intake ports 301 with different extension lengths may be arranged in the height direction with their left ends aligned (Modification 2). In these cases, the suction force in the gas suction unit 300 gradually weakens along the conveying direction A1 of the tablet T, that is, toward the print head device 24 (the right side in FIG. 17 and FIG. 18), so that the airflow generated by the suction of the gas suction unit 300 is prevented from adversely affecting the printing of the print head device 24, and therefore the deterioration of the print quality can be more reliably prevented. In addition, near the intake port 301 downstream of the gas suction section 300 in the conveying direction A1, gas from the gas blowing section 200 is not supplied directly, but is only supplied via the guide plate 104, so there is no problem even if the amount of air sucked in from the intake port 301 decreases.

[0124] Here, in Fig. 17, the upper side of the triangular intake port 301 is inclined, but conversely, the lower side may be inclined, or both may be inclined. Also, in Fig. 18, the intake ports 301 are arranged from the top in order of the shortest extension length, but conversely, they may be arranged from the bottom in order of the shortest extension length, or they may be arranged regardless of the extension length. Also, it is possible to use circular or elliptical intake ports 301 arranged in one or more rows along the conveying direction A1 of the tablets T. be.

[0125] (Modification 3 of the gas suction part) In the above description, it has been exemplified that the suction force of the gas suction unit 300 can be adjusted by changing the height direction length of the intake port 301 of the gas suction unit 300, but the present invention is not limited thereto. For example, as shown in FIG. 19, a suction force adjustment member 304 may be provided in the internal flow path 303 of the gas suction unit 300. As shown in FIG. 20, the suction force adjustment member 304 has a rectangular (slit-shaped) through hole 304a extending in the conveying direction A1 of the tablet T, and is provided inside the internal flow path 303 so as to block the internal flow path 303, and adjusts the suction force by changing the flow rate of the gas passing through the internal flow path 303. Several types of suction force adjustment members 304 with different slit widths of the through hole 304a (width in the direction perpendicular to the conveying direction A1 of the tablet T in the through hole 304a in the horizontal plane) are prepared, and one of the suction force adjustment members 304 is selected and used according to the required suction force, so that the suction force of the gas supply unit 300 can be easily adjusted.

[0126] In Fig. 19, the through-holes 304a of the suction force adjustment member 304 are formed in a rectangular shape extending in the conveying direction A1 of the tablet T, but this is not limited thereto and may be formed in various shapes such as a circular shape, an elliptical shape, a triangular shape, etc. The number of through-holes 304a is also not limited and may be multiple. For example, multiple through-holes 304a having circular or elliptical shapes may be formed to be aligned in a line in the conveying direction A1 of the tablet T, may be formed to be aligned in multiple rows (for example, two or three rows), or may be formed irregularly (randomly).

[0127] In addition, the suction force adjustment member 304 forming the through hole 304a may be removable and may be replaced when changing the type of tablet T to be printed. In this way, the suction force can be easily adjusted even if the printing target is changed. The suction force adjustment member 304 may be attached anywhere in the gas suction section 300, and may be attached to the intake port 301 or the exhaust port 302.

[0128] (Modification of cover) In the above description, the through-holes 100a of the cover 100 are formed in a line along the conveying direction A1 of the tablets T, but the present invention is not limited to this and the through-holes 100a may be arranged in two or more lines, or may be formed randomly instead of in a line. As shown in Fig. 21 (a plan view showing the bottom surface of the cover 100), the through-holes 100a may be formed in a slit shape.

[0129] In the above description, the inspection device 22, the first imaging device 23, the print head device 24, and the second imaging device 25 are housed in the cover 100, but this is not limited to the above. By providing the cover 100, powder does not adhere to the inspection device 22, the first imaging device 23, the print head device 24, and the imaging device 25 themselves, and only the cover 100 can be removed and washed, which is efficient when changing the type of tablet T. However, if the adhesion removal mechanism functions sufficiently, the cover 100 does not need to be provided. In this case, the guide plate 104 is attached to the gas blowing unit 200 itself. By eliminating the cover 100 in this way, it is possible to freely change the height positions of the inspection device 22, the first imaging device 23, the print head device 24, and the second imaging device 25.

[0130] <Other embodiments> In the above-described embodiments, the pulley bodies 21b, 80, and 90 have the driving source, but the present invention is not limited to this, and the pulley bodies 21b, 80, and 90 may be driven.

[0131] In addition, in each of the above-described embodiments, the first rotating body and the second rotating body are illustrated as timing pulleys, but the present invention is not limited to this, and sprockets or the like may also be used.

[0132] In addition, in each of the above-described embodiments, an example is given of transporting the tablets T in two rows, but this is not limited to this, and the number of rows may be one row, three rows, or four or more rows, and is not particularly limited.

[0133] In addition, in each of the above-described embodiments, only one conveyor belt 21a is provided, but the present invention is not limited to this, and two or more conveyor belts may be provided, and the number of conveyor belts is not particularly limited. For example, a plurality of conveyor belts 21a may be arranged in parallel.

[0134] In addition, in each of the above-described embodiments, the use of circular suction holes as the suction holes 21g of the conveyor belt 21a has been exemplified, but this is not limited thereto, and it is possible to use suction holes having a rectangular, elliptical, slit-like shape, etc., and the shape of the suction holes 21g of the conveyor belt 21a is not particularly limited.

[0135] In addition, in each of the above-mentioned embodiments, a print head 24a is provided for each transport path of the tablets T, 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.

[0136] In addition, in each of the above-described embodiments, a print head in which the nozzles 24b are arranged in a line is exemplified as the inkjet print head 24a, but this is not limited thereto, and for example, a print head in which the nozzles 24b are arranged in multiple lines may be used. Also, a plurality of print heads 24a may be arranged along the conveying direction A1 of the tablets T. Also, the printing method is not limited to the inkjet method, and may be a laser marking method or a transfer drum method.

[0137] In addition, in each of the above-mentioned embodiments, the first printing device 20 and the second printing device 30 are arranged one on top of the other to print 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 and print only one side of the tablet T.

[0138] In addition, in each of the above-described embodiments, the gas blowing section 42a is provided in the non-defective product collecting section 42, but the present invention is not limited thereto, and may be provided, for example, at the end of the conveying device 21 on the second conveying device 31 side, or at a location where the tablets T are transferred from the delivery feeder 13 to the conveying device 21. In other words, the gas blowing section 42a may be used at a location where it is desired to remove the tablets T from the conveying belt 21a.

[0139] Further, in each of the above-described embodiments, the gas blowing portion 42a constantly blows out gas during processing, but the present invention is not limited to this, and the gas may be blown out intermittently.

[0140] Here, the above-mentioned tablets can include tablets used for medicine, food, cleaning, industrial or aromatic purposes. Tablets include uncoated tablets (plain tablets), sugar-coated tablets, film-coated tablets, enteric tablets, gelatin-coated tablets, multi-layer tablets, dry-coated tablets, and various capsule tablets such as hard capsules and soft capsules. Tablets can have various shapes such as disks, lenses, triangles, and ellipses. When the tablets to be printed are for medicine or food, 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.

[0141] 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 implemented 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 in the scope and spirit of the invention, and are included in the scope of the invention and its equivalents described in the claims. [Explanation of symbols]

[0142] 1 Tablet printing equipment 21 Conveying device (tablet conveying device) 21a Conveyor belt 21b Pulley body (first rotating body) 21c Driven pulley (second rotating body) 21f Chamber (duct) 21g suction hole 21h Rotation axis 24 Print head unit 31 Conveying device (tablet conveying device) 31a Conveyor belt 31f Chamber (duct) 34 Print head unit 61 Chamber body 62a Suction tube 62b Suction tube 63 Bulkhead 64 Bulkhead 65 Flooring 66 Suction force reducing member (suction force adjusting device) 70a through hole 71 Conveyor pulley 72 Conveyor pulley 73 Guide pulley 74 Guide pulley 80 Pulley body (first rotating body) 80a through hole 81 Conveyor pulley 82 Conveyor pulley 83 Guide pulley 90 Pulley body (first rotating body) 90a interior space 91 Conveyor pulley 92 Conveyor pulley T Tablet B1 Section B2 Section

Claims

1. A conveying and processing device that conveys a plurality of tablets and performs a predetermined process, a conveyor belt having a plurality of suction holes on an outer surface thereof, and conveying the tablet along a predetermined conveying path while applying negative pressure to the suction holes to suction and hold the tablet; a gas blowing unit that blows gas toward the outer surface of the conveyor belt; a suction mechanism that sucks the tablet powder blown off from the outer surface by blowing the gas onto the outer surface; having a camera that photographs the tablets transported by the transport belt at an inspection position on the transport path; An inspection processing unit that inspects the tablet based on the image captured by the camera; and The gas blowing section and the suction mechanism are a conveying and processing device that blows the gas toward the outer surface of the conveying belt upstream of the inspection position on the conveying path and sucks up the tablet powder blown away from the outer surface.

2. The conveying and processing device according to claim 1 , The gas blowing unit is connected to a gas supply unit via a flow rate regulating valve that regulates the flow rate of the gas, The suction mechanism includes an intake port that is an opening for sucking air from the upper surface of the conveyor belt, and a pump that sucks gas from the intake port.

3. The conveying and processing device according to claim 2, A conveying and processing device in which the flow rate of the gas supplied from the gas blowing section and the suction force of the air sucked from the intake port applied by the pump are set by the flow control valve so that the position of the tablets on the conveying belt does not change.

4. 4. The conveying and processing device according to claim 1, further comprising a print head for printing on the tablets conveyed by the conveyor belt, A tablet printing device characterized in that the printing head is provided downstream of the gas blowing section in the tablet transport direction.

Images