JP7080694B2 - Tablet printing equipment - Google Patents

Description

Embodiments of the present invention relate to a tablet printing device.

A tablet printing device that prints using an inkjet printing head for printing characters, symbols, and the like on a tablet is known. This tablet printing device transports tablets by a transport belt, and ink is directed from the ejection port (opening of the nozzle) of an inkjet printing head arranged above the transport belt toward the tablets passing below the print head. Discharge and print on tablets.

Japanese Unexamined Patent Publication No. 7-081050

By the way, the tablet sucked and transported by the transport belt may sway on the transport belt. This is due to the case where the vibration when the tablet is supplied by dropping it from above the conveyor belt continues, or the moving state of the conveyor belt slightly shakes. If such shaking of the tablet continues to a position where it passes under the print head, normal printing cannot be performed. Therefore, it is necessary to suppress the shaking movement of the tablet on the transport belt as much as possible.

INDUSTRIAL APPLICABILITY The present invention provides a tablet printing apparatus capable of suppressing the shaking movement of a tablet sucked and transported by a transport belt and capable of printing with good quality.

The tablet printing apparatus according to the embodiment of the present invention includes a transport belt having a suction hole for sucking the tablet and an inkjet printing head for printing on the tablet transported by the transport belt, and the transport belt sucks the tablet. It has a plurality of protrusions formed around the hole to contact and support the tablet, and a recess formed between the protrusions and communicating with the suction hole, the plurality of protrusions being individual of the plurality of protrusions. The area of the top surface of the protrusion is smaller than the area of the individual bottom surface of the protrusions, the individual sides of the protrusions each have an inclined surface, and the protrusions have the shape of a cone, and the protrusions are the surface of the conveyor belt. It is arranged in a row on top, and the rows of protrusions are formed so as to line up along the direction in which they intersect in the horizontal plane with respect to the transport direction of the tablet. The tablet is supported with a gap formed between the tablets, and a suction force is applied to the gap and the recessed space through the suction hole to suck the tablet.

According to the embodiment of the present invention, there is provided a tablet printing apparatus capable of suppressing the shaking movement of a tablet sucked and transported by a transport belt and capable of printing with good quality.

It is a figure which shows the schematic structure of the tablet printing apparatus which concerns on this embodiment. It is a top view which shows a part of the 1st printing apparatus which concerns on this embodiment. It is a top view which shows the shaking prevention area of the transport belt which concerns on this embodiment. It is a figure which shows the protrusion provided in the transport belt. It is a top view which shows the arrangement example of the protrusions provided on a transport belt. It is a figure which shows the state of the tablet which shakes on the conventional (no protrusion) transport belt. It is a figure which shows the state of the tablet which shakes on a transport belt. It is a figure which shows the state which the tablet placed on the transport belt was seen from the direction parallel to the transport direction. It is a figure which shows the state which the tablet placed on the transport belt was seen from the direction orthogonal to the transport direction. It is a figure which shows an example of the shape of a tablet. FIG. 10 is a diagram showing a state of a tablet in which the tablet of FIG. 10 swings on a conventional (no protrusion) transport belt. It is a figure which shows an example of the state which the tablet of FIG. 10 rests on a transport belt. FIG. 3 is a plan view showing an example of a state in which the tablet of FIG. 10 is placed on a transport belt. It is a top view which shows the arrangement example of the protrusions provided on a transport belt. It is a top view which shows the arrangement example of the protrusions provided on a transport belt. It is a top view which shows the transport belt which formed the groove. It is a figure which shows an example of the state which the tablet of FIG. 10 rests on a transport belt.

An embodiment of the present invention will be described with reference to the drawings.

(Basic configuration)
As shown in FIG. 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 recovery device 40, and a control device 50. It is equipped with. The first printing device 20 and the second printing device 30 have basically the same structure.

The supply device 10 has a hopper 11, an alignment feeder 12, and a delivery feeder 13. The supply device 10 is configured to be able to supply the tablet 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 accommodates 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 delivery feeder 13. The delivery feeder 13 sequentially sucks the tablets T on the alignment feeder 12 and conveys them to the first printing device 20 in two rows, and supplies the tablets T 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. As the alignment feeder 12 and the delivery feeder 13, for example, a belt transport mechanism can be used.

The first printing device 20 includes a transport device (tablet transport device) 21, a detection device 22, a first image pickup device (imaging device for printing) 23, a print head device 24, and a second image pickup device ( An image pickup device) 25 for inspection, a drying device 26, and a cleaning device 27 are provided.

The transfer device 21 includes a transfer belt 21a, a pulley body 21b which is a drive pulley, a plurality of driven pulleys 21c (three in the example of FIG. 1), a motor (drive unit) 21d, a position detector 21e, and a suction chamber 21f. is doing. The transport belt 21a is formed in an endless shape and is bridged to the pulley body 21b and each driven pulley 21c. The pulley body 21b and each driven pulley 21c are rotatably provided on the main body of the apparatus, and the pulley body 21b is connected to the motor 21d. The motor 21d is electrically connected to the control device 50, and its drive is controlled by the control device 50. The position detector 21e is a device such as an encoder and is attached to the motor 21d. The position detector 21e is electrically connected to the control device 50 and transmits a detection signal to the control device 50. The control device 50 can obtain information such as the position, speed, and movement amount of the conveyor belt 21a based on the detection signal. The transport device 21 rotates the transport belt 21a together with each driven pulley 21c by the rotation of the pulley body 21b by the motor 21d, and the tablet T on the transport belt 21a is directed by the arrow A1 in FIGS. 1 and 2 (transport direction). Transport to A1).

Here, as shown in FIG. 2, a plurality of circular suction holes 21g are formed on the surface of the transport belt 21a. Each of these suction holes 21g is a through hole for sucking the tablet T, and is arranged in two rows in parallel along the transport direction A1 so as to form two transport paths. Each suction hole 21g is connected to a suction chamber 21f (see FIG. 1), and it is possible to obtain a suction force by the suction chamber 21f. The suction chamber 21f is a chamber for applying (acting on) a suction force to the tablet T placed in each suction hole 21g of the transport belt 21a. An intake device such as a pump is connected to the suction chamber 21f via a suction pipe (neither is shown), and the inside of the suction chamber 21f is depressurized by the operation of the suction device. The suction tube is connected to substantially the center of the side surface (plane parallel to the transport direction A1) of the suction chamber 21f. Further, the intake device is electrically connected to the control device 50, and its drive is controlled by the control device 50.

The detection device 22 has a plurality of detection units 22a (two in the example of FIG. 2). The detection unit 22a is a tablet in a direction (for example, a direction orthogonal to the transport direction A1) that is downstream of the transport direction A1 and intersects the transport direction A1 in the horizontal plane with respect to the position where the tablet T is supplied in the transport belt 21a by the supply device 10. One is arranged for each transport path of T, and is provided above the transport belt 21a. The detection unit 22a detects the position of the tablet T on the transport belt 21a (the position in the transport direction A1) by the light emission / reception of the laser beam, and functions as a trigger sensor for each device located downstream. As the detection unit 22a, various laser sensors such as a reflection type 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.

The first image pickup apparatus 23 has a plurality of image pickup units 23a (two in the example of FIG. 2). One image pickup unit 23a is provided for each transport path of the tablet T in a direction (for example, a direction orthogonal to) which is downstream of the transport direction A1 and intersects the transport direction A1 in the horizontal plane from the position where the detection device 22 is provided. They are arranged one by one and provided above the transport belt 21a. Based on the above-mentioned position information of the tablet T, the image pickup unit 23a takes an image at the timing when the tablet T reaches directly under the image pickup unit 23a, and acquires an image (image for printing) including the upper surface of the tablet T. The acquired image is transmitted to the control device 50. As the image pickup unit 23a, various cameras having an image pickup device such as a CCD (charge-coupled device) or CMOS (complementary metal oxide semiconductor) can be used. Each image pickup unit 23a is electrically connected to the control device 50, and their drive is controlled by the control device 50. Lighting for imaging is also provided as needed.

The print head device 24 has a plurality of inkjet print heads 24a (two in the example of FIG. 2). The print head 24a is on the downstream side of the transport direction A1 from the position where the first image pickup device 23 is provided, and is in a direction intersecting the transport direction A1 in the horizontal plane (for example, in a direction orthogonal to each other) for each transport path of the tablet T. They are arranged one by one and provided above the transport belt 21a. The print head 24a includes a plurality of nozzles 24b (see FIG. 2: however, only four are shown in the figure), and ink is individually ejected from these nozzles 24b. The print head 24a is provided so that the alignment direction in which the nozzles 24b are lined up intersects the transport direction A1 in the horizontal plane (for example, so as to be orthogonal to each other). The print head 24a prints at the timing when the tablet T reaches directly under the print head 24a based on the above-mentioned position information of the tablet T. As the print head 24a, various inkjet print heads having a driving element such as a piezoelectric element, a heat generating element, or a magnetostrictive element can be used. Each print head 24a is electrically connected to the control device 50, and their drive is controlled by the control device 50.

The second image pickup apparatus 25 has a plurality of image pickup units 25a (two in the example of FIG. 2). The image pickup unit 25a is located downstream of the position where the print head device 24 is provided in the transport direction A1 and intersects the transport direction A1 in the horizontal plane (for example, in a direction orthogonal to each other) for each transport path of the tablet T. They are arranged one by one and provided above the transport belt 21a. Based on the above-mentioned position information of the tablet T, the imaging unit 25a performs imaging at the timing when the tablet T reaches directly under the imaging unit 25a, and acquires an image (image for inspection) including the upper surface of the tablet T. The acquired image is transmitted to the control device 50. As the image pickup unit 25a, it is possible to use various cameras having an image pickup element such as a CCD or CMOS, as in the above-mentioned image pickup unit 23a. Each image pickup unit 25a is electrically connected to the control device 50, and their drive is controlled by the control device 50. Lighting for imaging is also provided as needed.

Returning to FIG. 1, the drying device 26 is positioned on the downstream side of the transport direction A1 from the position where the second image pickup device 25 is provided, and is provided, for example, below the transport device 21. The drying device 26 is a drying device common to the two rows of transport paths, and dries the ink applied to each tablet T on the transport belt 21a. As the drying device 26, various drying units 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 hot air or hot air can be used. The drying device 26 is electrically connected to the control device 50, and its drive is controlled by the control device 50.

The tablet T that has passed above the drying device 26 is transported along with the movement of the transport belt 21a, and reaches a position near the end of each driven pulley 21c on the transport belt 21a. At this position, the suction action does not work on the tablet T, the tablet T is released from the state of being held by the transport belt 21a, and is transferred from the first printing device 20 to the second printing device 30.

Further, a cleaning device 27 for cleaning the surface of the transport belt 21a is provided on the downstream side of the transport direction A1 at the position where the tablet T is delivered from the first printing device 20 to the second printing device 30. The cleaning device 27 is provided, for example, in the vicinity of the lower driven pulley 21c. Although not shown, the cleaning device 27 has a rotating brush, and the rotating brush is urged by an elastic body such as a spring to rotate while being pressed against the surface of the transport belt 21a. The entire rotating brush is covered with a cover, and the inside of this cover is sucked. The cleaning device 27 scrapes and removes powder and the like generated from the tablets adhering to the surface of the transport belt 21a. The cleaning device 27 is electrically connected to the control device 50, and its drive is controlled by the control device 50.

The second printing device 30 includes a transport device 31, a detection device 32, a first image pickup device (printing image pickup device) 33, a print head device 34, and a second image pickup device (inspection image pickup device). ) 35, a drying device 36, and a cleaning device 37. The transfer device 31 includes a transfer belt 31a, a pulley body 31b which is a drive pulley, a plurality of driven pulleys 31c (three in the example of FIG. 1), a motor (drive unit) 31d, a position detector 31e, and a suction chamber 31f. is doing. Since each element constituting the second printing device 30 has basically the same structure as the corresponding component of the first printing device 20 described above, the description thereof will be omitted. The transport direction of the second printing apparatus 30 is the direction of the arrow A2 in FIG. 1 (transport direction A2).

The collection device 40 includes a defective product collection device 41 and a non-defective product collection device 42. The recovery device 40 is positioned on the downstream side in the transport 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 is used to collect the defective tablet T. It is collected, and the non-defective tablet T is collected by the non-defective product collection device 42.

The defective product collecting device 41 has an injection nozzle 41a and an accommodating portion 41b. The injection nozzle 41a is provided in the suction chamber 31f of the second printing device 30, and injects gas (for example, air) toward the tablet T (defective tablet T) conveyed by the transfer belt 31a. , The tablet T is dropped from the transport belt 31a. At this time, the gas injected from the injection nozzle 41a passes through the suction hole of the transport belt 31a (similar to the suction hole 21g shown in FIG. 2) and hits the tablet T. The injection nozzle 41a is electrically connected to the control device 50, and its drive is controlled by the control device 50. The accommodating portion 41b receives and accommodates the tablet T dropped from the transport belt 31a.

The non-defective product recovery device 42 has a gas blowing unit 42a and an accommodating unit 42b. The non-defective product recovery device 42 is positioned and provided on the downstream side in the transport direction A2 from the position where the defective product recovery device 41 is provided. The gas blowing portion 42a is provided in the transport device 31 of the second printing device 30, at the end of the transport device 31, that is, at the end of the transport belt 31a on the side of each driven pulley 31c. For example, during the printing process, the gas blowing unit 42a always blows gas (for example, air) toward the transport belt 31a and drops the tablet T from the transport belt 31a. At this time, the gas blown out from the gas blowing portion 42a passes through the suction hole of the transport belt 31a (similar to the suction hole 21g shown in FIG. 2) and hits the tablet T. As the gas blowing portion 42a, for example, an air blow having a slit-shaped opening extending in a direction intersecting the transport direction A2 in a horizontal plane (for example, a direction orthogonal to each other) can be used. The gas blowing unit 42a is electrically connected to the control device 50, and its drive is controlled by the control device 50. The accommodating portion 42b receives and accommodates the tablet T dropped from the transport belt 31a.

Here, the tablet T that has passed through the defective product collecting device 41 is transported along with the movement of the transport belt 31a, and reaches a position near the end of each driven pulley 31c side of the transport belt 31a. Although the suction action does not work on the tablet T at this position, by providing the gas blowing portion 42a at this position as well, the tablet T can be reliably dropped from the transport belt 31a and collected in the accommodating portion 42b.

The control device 50 includes an image processing unit 51, a printing processing unit 52, an inspection processing unit 53, and a storage unit 54. The image processing unit 51 processes the image. The print processing unit 52 performs processing related to printing. The inspection processing unit 53 performs processing related to inspection. The storage unit 54 stores various information such as processing information and various programs. Such a control device 50 controls a supply device 10, a first printing device 20, a second printing device 30, and an individual detection device 22 of the first printing device 20 and the second printing device 30. , 32 to receive the position information of the tablet T, images transmitted from the individual image pickup devices 23, 25, 33, 35 of the first printing device 20 and the second printing device 30 and the like.

(Conveyor belt)
As shown in FIG. 3, a region (hatched portion) having a predetermined width including each row of two rows of suction holes 21g of the transport belt 21a in the center is a region (hereinafter referred to as an anti-sway region) Ep on which the tablet T can be placed. If there is, the protrusion 170 shown in FIG. 4 is formed in each of the shaking prevention regions Ep. The shaking prevention region Ep is a region in which the tablet T is likely to be located on the transport belt 21a when the tablet T is delivered from the delivery feeder 13 to the transport belt 21a, and is continuous in the transport direction A1. However, in the direction orthogonal to the transport direction A1, the range is larger than the size of the tablet T. The tablet T sucked by the delivery feeder 13 is released from the suction and falls on the transport belt 21a. The dropped tablet T will be located within a certain range on the transport belt 21a. More specifically, the length of the dropped tablet T in the direction orthogonal to the transport direction A1 in the range where the dropped tablet T is located on the transport belt 21a is about 1.5 times the size of the tablet T.

As shown in FIG. 4, each of the protrusions 170 has a frustum shape, which is one of the frustum shapes. That is, the protrusion 170 has a bottom surface 170c and a top surface 170a, and the area of the top surface 170a is smaller than that of the bottom surface 170c. The side surface 170b connecting the bottom surface 170c and the top surface 170a is a flat slope.

Further, as shown in FIG. 5, the protrusions 170 are arranged in a row in a row. A plurality of the row-shaped protrusions 170 are formed in parallel, and are formed in a planar shape in the anti-sway region Ep on the surface of the transport belt 21a. Then, as will be described later with reference to FIG. 8, the recesses 171 formed between the plurality of protrusions 170 are connected in a row between the rows of the protrusions 170. Further, the row direction of the row-shaped protrusions 170 is inclined by 45 ° with respect to the transport direction A1. That is, the protrusions 170 are lined up along the direction intersecting the transport direction A1 of the tablet T in the horizontal plane. The two rows tilted 45 ° counterclockwise and 45 ° clockwise with respect to the transport direction A1 are formed so as to intersect each other. Therefore, the bottom surface 170c and the top surface 170a of the protrusion 170 are square in a plan view, and their sides are inclined by 45 ° with respect to the transport direction A1.

As described above, a plurality of protrusions 170 are arranged in a row, and the row of the protrusions 170 and the pitch of the rows are set in the range of 1/15 or more and 1/5 or less of the size D of the tablet T, preferably. , 1/10. When the tablet T is circular, the size D of the tablet T is its diameter. When the tablet T is elliptical and has a major axis and a minor axis, the size D of the tablet T is the smaller one, that is, the size of the minor axis.

For example, if the tablet T is a circular tablet and its diameter is 7 mm, rows of protrusions 170 are lined up at a pitch of 0.7 mm, which is 1/10 of the diameter.

Further, in the present embodiment, the height of each protrusion 170 is set in the range of 1/50 or more and 1/2 or less of the thickness (maximum thickness) of the tablet T, preferably the thickness of the tablet T (the maximum thickness). It is set to 1/10 of the maximum thickness). However, the height of each protrusion 170 is set to a height of at least 100 μm or more. The diameter (maximum diameter) of the tablet T is approximately 5 to 15 mm, and the thickness (maximum thickness) is 2 to 8 mm.

Further, as described later, there is a tablet T having a recess Ta (see FIG. 10) on the surface of the tablet T so as to cover the entire surface of the tablet T. When there is such a large recess Ta, the height of each protrusion 170 may be set in the range of 1/50 or more and 1 or less of the height of the recess Ta with reference to the height of the recess Ta.

The protrusion 170 is formed by pressing an uneven mold against the surface of the transport belt 21a and simultaneously applying heat. Therefore, the protrusion 170 is integrally provided on the transport belt 21a. Further, a recess 171 is formed between the plurality of protrusions 170 and the protrusions 170. The material of the transport belt 21a is, for example, urethane resin, and its hardness is Hs90. It should be noted that various materials can be applied as long as they are flexible and durable, and even if the tablets are edible, there is no problem in food hygiene. The hardness of the transport belt 21a may be selected in the range of Hs50 to 120. The flexibility can be expressed by, for example, an elastic modulus, a deformation rate, and the like, and a large flexibility includes a small elastic modulus and a large deformation rate. Further, as shown in FIG. 7, the height of the bottom surface 171a of the recess 171 is located at a position lower than the height A of the surface of the transport belt 21a outside the region where the protrusion 170 is formed.

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

First, various information such as print data required for printing is stored in the storage unit 54 of the control device 50. Then, when a large number of tablets T to be printed are charged into the hopper 11 of the supply device 10, the tablets T start to be sequentially supplied from the hopper 11 to the alignment feeder 12, and are arranged and moved in two rows by the alignment feeder 12. The tablets T moving in the two rows are sequentially supplied to the transport belt 21a by the delivery feeder 13. The transport belt 21a is rotated in the transport direction A1 by the rotation of the pulley body 21b and each driven pulley 21c by the motor 21d. Therefore, the tablets T supplied on the transport belt 21a are transported in two rows on the transport belt 21a at a predetermined moving speed. The transport belt 31a is also rotated in the transport direction A2 by the rotation of the pulley body 31b and each driven pulley 31c by the motor 31d.

After that, the tablet T on the transport belt 21a is detected by the detection device 22. As a result, the position information of the tablet T (the position in the transport direction A1) is acquired and input to the control device 50. The position information of the tablet T is stored in the storage unit 54 and used in the post-treatment. Next, the tablet T on the transport belt 21a is imaged by the first image pickup device 23 at the timing based on the position information of the tablet T described above, and the captured image is transmitted to the control device 50. Based on the individual images transmitted from the first image pickup apparatus 23, the misalignment information of the tablet T (for example, the misalignment of the tablet T in the X direction, the Y direction, and the θ direction) is generated by the image processing unit 51. It is stored in the storage unit 54. Based on the misalignment information of the tablet T, printing conditions (ink ejection position, ejection speed, etc.) for the tablet T are set by the printing processing unit 52 and stored in the storage unit 54.

Next, the individual tablets T on the transport belt 21a are printed head devices based on the above-mentioned printing conditions at the timing based on the position information of the above-mentioned tablets T, that is, at the timing when the tablets T reach the lower part of the print head device 24. Printing is executed by 24. In each print head 24a of the print head device 24, ink is appropriately ejected from each nozzle 24b, and information such as characters (for example, alphabet, one pseudonym, number) and marks (for example, symbols, figures) is printed on the upper surface of the tablet T. To.

The tablet T on which the information is printed is imaged by the second image pickup device 25 at a timing based on the position information of the tablet T described above, and the captured image is transmitted to the control device 50. Based on the individual images transmitted from the second image pickup apparatus 25, print position information indicating the print position of the print pattern for each tablet T is generated by the image processing unit 51 and stored in the storage unit 54. Based on the print position information, the inspection processing unit 53 determines whether the tablet T is printable or not, and the print quality result information indicating the print quality result for each tablet T is stored in the storage unit 54. For example, it is determined whether or not the print pattern is printed at a predetermined position on the tablet T.

The tablet T after the inspection is transported along with the movement of the transport 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 to which the ink has been dried is transported with the movement of the transport belt 21a. It is located near the end of each driven pulley 21c on the transport belt 21a. At this position, the suction action does not work on the tablet T, the tablet T is released from the state of being held by the transport belt 21a, and is passed from the first printing device 30 to the second printing device 30.

After that, the second printing apparatus 30 also performs the printing process and the inspection process in the same manner as described above. The tablet T after the inspection is transported along with the movement of the transport belt 31a and passes above the drying device 36. Then, the tablet T whose ink has dried reaches the defective product recovery device 41. The defective tablet T is dropped from the transport belt 31a by the gas ejected from the injection nozzle 41a and collected by the accommodating portion 41b. On the other hand, the non-defective product tablet T passes through the defective product recovery device 41 and reaches the non-defective product recovery device 42. At this position, the non-defective tablet T does not act on the tablet T by suction, and is dropped away from the transport belt 31a by the gas blown out from the gas blowing portion 42a and collected by the accommodating portion 42b.

By the way, in the printing process as described above, the tablet T supplied on the suction hole 21g is held on the transport belt 21a by suction from the suction hole 21g, but the tablet T supplied to the transport belt 21a is It may sway on the transport belt 21a due to vibration when it is supplied or acceleration / deceleration in the transport direction that occurs slightly during transport. In particular, when the shape of the portion of the tablet T in contact with the surface of the transport belt 21a is a curved surface, the swaying motion is not easily attenuated, and the swaying motion may remain so that the printing is displaced during printing with the print head 24a.

Since printing on the print head 24a is performed in accordance with the movement of the tablet T passing under the print head 24a, the position of the tablet T relatively moving with respect to the print head 24a due to the shaking motion of the tablet T. If the print is misaligned, the print will be misaligned depending on the amount of misalignment at that position.

As described above, the transport belt 21a is provided with a suction hole 21g for sucking the tablet T, and the tablet T is sucked and held on the surface of the transport belt 21a by suction from the suction hole 21g. However, when the surface of the tablet T is a curved surface, it is supported by one point of the apex of the curved surface on the transport belt 21a, and when the tablet T is swaying, the swaying is not easily attenuated.

Further, as the tablet T, there is a so-called uncoated tablet in which the powder of the material is compacted. In the case of such an uncoated tablet, powder is more likely to be generated than the tablet T during the printing process. Such powder is scattered in the tablet printing apparatus 1 and adheres to the surface of the transport belt 21a. If powder adheres to the surface of the transport belt 21a, the tablet T will be placed on the powder. Even if the tablet T is sucked and held by the transport belt 21a with the powder sandwiched between them, the powder acts as a roller and the tablet T tends to swing. This is because, for example, even if the surface of the curved surface of the tablet T is fitted in the suction hole 21g of the transport belt 21a, if there is powder adhering to the edge of the suction hole 21g, the tablet T is likely to shake. ..

FIG. 6 shows how the tablet T having a curved surface swings on the surface of the transport belt 21a without the protrusion 170. FIG. 7 shows how the tablet T having a curved surface swings on the surface of the transport belt 21a having the protrusion 170. 8 and 9 show that the tablet T having a curved surface is supported by a plurality of protrusions 170 on the surface having protrusions 170 on the transport belt 21a.

FIG. 8 is a schematic view of the state in which the tablet T is placed on the transport belt 21a as viewed from the side surface of the tablet T (viewed from a direction parallel to the transport direction A1), from the back to the front with respect to the paper surface. It shows the state of being transported. That is, the left-right direction in the figure is the width direction of the transport belt 21a. FIG. 9 is a view of a side surface (viewed from a direction orthogonal to the transport direction A1) in which the tablet T is transported from left to right on the paper surface. That is, the left-right direction in the figure is the transport direction A1.

The subsequent figure showing the contact between the protrusion 170 and the tablet T is a view of the state in which the tablet T is placed on the transport belt 21a from the side surface of the tablet T, and the state is modeled in an easy-to-understand manner. It was done. Therefore, not all protrusions are shown. Further, unless otherwise specified, it indicates a state in which the paper is conveyed from the back to the front with respect to the paper surface.

When the surface of the tablet T has a curved surface, the tablet T supplied on the transport belt 21a is supported at one point on the surface of the transport belt 21a in the transport belt 21a having no protrusion 170 on the surface, as shown in FIG. By swinging with that one point as a fulcrum, it is difficult to suppress the swinging movement. On the other hand, as shown in FIG. 7, in the transport belt 21a having protrusions 170 on the surface, the tablet T swings in a state of being in contact with the plurality of protrusions 170, and the protrusions 170 are dispersedly hit the surface of the tablet T. Therefore, the swinging movement is likely to be hindered. That is, the vibration is limited by the contact and support at a plurality of separated points, and the vibration of the tablet T is easily attenuated.

Further, as shown in FIGS. 8 and 9, the transport belt 21a of the present embodiment is provided with a protrusion 170 around the suction hole 21g in the shaking prevention region Ep. The term "around the suction hole 21g" is within the area range of the tablet T when the tablet T is sucked into the suction hole 21g, and is sucked into the bottom surface of the groove 21h formed in the transport belt 21a, which will be described later. When the hole 21g is formed, the surface of the transport belt 21a outside the groove 21h is also included in the range. Therefore, even if the surface of the tablet T is curved, the tablet T is supported in contact with a plurality of protrusions 170 in a direction intersecting the transport direction A1 and the transport direction A1. Even if the tablet T is rocking, it is supported at a plurality of separated points, so that the movement is rapidly attenuated. Further, even if acceleration is applied during transportation, the tablet T does not easily shake.

Further, a recess 171 communicating with the suction hole 21g is formed between the plurality of protrusions 170. The protrusion 170 supports the tablet T in a state where a gap is formed between the surface of the tablet T on the transport belt 21a side and the suction hole 21g, and the suction force is applied to the gap and the space of the recess 171 through the suction hole 21g. To suck the tablet T. As a result, even if the powder adheres to the surface of the transport belt 21a, the powder has fallen into the recess 171 between the plurality of protrusions 170, so that the powder does not touch the tablet T and the transport belt 21a of the tablet T does not touch the powder. The action of reducing the contact resistance to the belt is suppressed.

The area of the surface (upper surface 170a) of the plurality of protrusions 170 on the side in contact with the tablet T is smaller than the area of the surface (bottom surface 170c) in which the transport belt 21a and the individual protrusions 170 are in contact with each other. Each side of 170 has an inclined surface. As a result, the area of the upper surface 170a can be reduced without changing the area of the bottom surface 170c of the protrusion 170 as compared with the protrusion having no inclined surface. Therefore, the tablet T can be stably supported without changing the area of the bottom surface 170c. Moreover, since the upper surface 170a can be made smaller, even if powder adheres to the edge or apex of the upper surface 170a of the protrusion 170 or the upper surface 170a thereof, the contact area with the tablet T is very small and the area is small. The surface pressure becomes high, and even if powder is present, it does not lead to a decrease in contact resistance that causes the tablet T to shake.

Further, a plurality of protrusions 170 are arranged in a row over the suction hole 21g, and a plurality of rows of protrusions 170 are arranged in a row, and a recess 171 connected in a row between the rows of the protrusions 170 is connected to the suction hole 21g. There is. As a result, the suction force acting on the tablet T by suction from the suction hole 21g also acts on the space of the recess 171 between the plurality of protrusions 170, so that suction is performed in a range larger than the size of the suction hole 21g. Force can be applied to the tablet T. Therefore, the suction-holding force of the tablet T becomes stronger, and the shaking movement of the tablet T is further suppressed. Further, since a plurality of rows of recesses 171 are formed across the plurality of suction holes 21g, not only the suction force from one suction hole 21g but also the suction force from the plurality of suction holes 21g is applied to the recess 171. It can also act on space. Therefore, the suction force acting on the tablet T can be made uniform without the tablet T being sucked unevenly to the specific suction hole 21g, and the tablet T is tilted or fluttered when sucked into the suction hole 21g. Can be suppressed.

Further, since the height of the bottom surface 171a of the recess 171 is lower than the height A of the surface of the transport belt 21a outside the region where the protrusion 170 is formed, the surface of the transport belt 21a is formed from the tablet T. Even if the generated powder adheres, the powder falls into the recess 171 and stays on the bottom surface 171a, so that it is possible to prevent the powder from adhering to the upper surface 170a of the protrusion 170 or the surface of the tablet T. As a result, the action of reducing the contact resistance of the tablet T to the transport belt 21a due to the adhesion of the powder is suppressed, and the shaking movement of the tablet T can be suppressed.

Further, the recesses 171 formed between the plurality of protrusions 170 on the surface of the transport belt 21a are connected in a row on the surface of the transport belt 21a. Further, since the outer angle θ formed by the side surface 170b of the protrusion 170 and the bottom surface 171a of the recess 171 is an obtuse angle, it becomes easy for the cleaning device 27 to scrape out the powder in the shaking prevention region Ep on the surface of the transport belt 21a. Increases powder removal rate. This makes it possible to further suppress the influence of powder.

Therefore, by using the transport belt 21a having the protrusion 170 on the surface of the present embodiment, it is possible to suppress the swaying motion of the tablet T sequentially supplied to the transport belt 21a from the transfer feeder 13 located above the transport belt 21a. As a result, the tablet T conveyed by the conveying belt 21a can pass directly under the print head 24a without shaking or in a state where the shaking is small, and good printing on the tablet T becomes possible. This also applies to the second printing device 30 in which the tablet T is delivered from the first printing device 20.

FIG. 10 shows the tablet T when a recess for dividing the tablet T is provided on one side of the surface. 10 (A) shows the front surface of the tablet T, FIG. 10 (B) shows the upper surface, and FIG. 10 (C) shows the side surface. Such dents vary in shape from groove-shaped to large dents as shown in FIG. In particular, when there is a large dent as shown in FIG. 10, when the surface with the dent is on the transport belt 21a side, the tip end portion of the edge portion of the dent shown by H in FIG. 10 comes into contact with the transport belt 21a. The tip of this H portion is often curved. Then, in the case of a dent that divides the tablet T into two, the H portions are two opposite positions. When the transport belt 21a is contacted at these two H portions, the suction hole 21g is not closed and the suction force acting on the tablet T becomes small. Since the tablet T is supported by the transport belt 21a at the two opposed H portions, it is difficult to swing in the direction connecting the two opposed H portions, but the two opposed H portions are H. It is very easy to swing in the direction orthogonal to the direction connecting the parts (Fig. 11).

By the way, since such an H portion has a sharp shape, it is easy to fit between the rows of protrusions 170 formed in a row on the transport belt 21a of the present embodiment. Further, the fitted H portion is in contact with a large number of protrusions 170, and the peripheral edge portion of the tablet T is contact-supported by the upper surface 170a or the side surface 170b of the protrusion 170 (FIG. 12). Therefore, it is possible to suppress the swaying motion in the direction orthogonal to the direction connecting the two H portions facing each other. The same effect can be obtained even if only one H portion of the two opposing H portions is fitted. Since the protrusion 170 of the present embodiment has a pyramidal trapezoidal shape, the side surface 170b has an inclined surface, and the surface area of the side surface 170b is larger than that of the rectangular parallelepiped-shaped protrusion having the same height. Therefore, there is a high possibility that the tip end portion of the recess of the tablet T comes into contact with the side surface 170b, and such fitting is likely to occur.

Which direction the position (direction) of the above-mentioned H portion faces with respect to the transport direction A1 is random. However, before the H portion is fitted into the recess between the rows of the protrusions 170 by the row of the trapezoidal protrusions 170 as a guide, the direction of the row of the protrusions 170 due to the movement such as the shaking movement of the tablet T. It becomes easier to position the orientation of the tablet T so as to imitate. Therefore, when the row of protrusions 170 has an angle with respect to the transport direction A1 and is particularly 45 °, it is difficult to swing in the direction parallel to or orthogonal to the transport direction A1 with respect to the transport direction A1. In many cases, the direction of the large dent of the tablet T is positioned in the direction of 45 °, and as a result, the shaking movement of the tablet T can be suppressed (FIG. 13).

Of course, even if the rows of protrusions 170 are arranged in two directions parallel to, perpendicular to, or perpendicular to the transport direction A1, the H portion is supported at a plurality of points, so that the shaking movement of the tablet T can be suppressed. ..

As described above, even if the tablet T has a large dent as shown in FIG. 10, by using the transport belt 21a having the protrusion 170 on the surface of the present embodiment, the tablet T sequentially supplied to the transport belt 21a. It is possible to suppress the shaking movement. As a result, the tablet T conveyed by the conveying belt 21a can pass directly under the print head 24a without shaking or in a state where the shaking is small, and good printing on the tablet T becomes possible.

Here, printing was performed on the tablet T using the conventional tablet printing device having no protrusion 170 and the tablet printing device 1 of the present embodiment, and the occurrence rate of printing defects was observed. The tablet printing apparatus 1 used a grid-shaped transport belt in which the row pattern of the protrusions 170 was tilted by 45 ° with respect to the transport direction A1 as shown in FIG. Further, as the tablet T, a circular shape having a diameter of 7 mm, having a concave portion Ta extending over almost the entire surface of one side as shown in FIG. 10, and having a curved surface on the other side was used.

First, in the conventional tablet printing apparatus having no protrusion 170, as a result of printing 10,000 tablets, the printing defect was about 500 tablets and the printing defect rate was about 5%.

Next, in the tablet printing apparatus 1 of the present embodiment, as a result of printing 10,000 tablets, the printing defect was about 10 tablets and the printing defect rate was about 0.1%.

In the supply of the tablet T to the transport belt 21a, whether the curved surface side of the surface of the tablet T comes into contact with the belt or the concave portion Ta side comes into contact with each other is stochastically about half. The tablet T is printed by the first printing device 20 and then inverted and printed by the second printing device 30. That is, both the curved surface side and the concave surface side of the surface of the tablet T are printed.

From the observation result of the occurrence rate of printing defects, in the transport belt 21a having the protrusion 170 of the present embodiment, the tablet T sways even if either the curved surface side or the concave surface side of the tablet T is in contact with the transport belt 21a. It can be seen that it can be suppressed and printing defects are reduced.

As described above, according to the present embodiment, the protrusion 170 is provided on the surface of the transport belt 21a. As a result, the swaying motion of the tablet T on the transport belt 21a can be suppressed, so that the deterioration of print quality due to the swaying motion of the tablet T can be suppressed. Although this embodiment has been mainly described with respect to the first printing apparatus 20, the same applies to the second printing apparatus 30.

<Other embodiments>
In the above-described embodiment, the surface of the transport belt 21a is formed with a row of protrusions 170 along two axes orthogonal to the transport direction A1 at 45 °, but the angle is not limited to this and the angle with respect to the transport direction A1 is not limited to this. It may be set appropriately, and may be, for example, 30 °. Further, as shown in FIG. 14, a row of protrusions 170 may be formed along two axes, an axis parallel to the transport direction A1 and an axis orthogonal to the transport direction A1. Further, as shown in FIG. 15, one protrusion 170 has a quadrangular pyramid shape, and the long side thereof has a dimension of the full width of the anti-sway region Ep or the transport belt 21a, and a plurality of quadrangular pyramid-shaped protrusions. 170s may be arranged in parallel in the transport direction A1. That is, the upper surface 170a and the bottom surface 170c of the protrusion 170 have a short side and a long side, and the rows of the plurality of protrusions 170 may be formed so as to be arranged in parallel so that the long side is orthogonal to the transport direction A1.

In the above-described embodiment, the protrusion 170 provided on the transport belt 21a has the shape of a pyramid having a bottom surface 170c and a top surface 170a, and the side surface 170b connecting the bottom surface 170c and the top surface 170a is a slope and a flat surface. Not limited to this, the side surface 170b connecting the bottom surface 170c and the top surface 170a may be a curved surface. The area of the surface (upper surface 170a) of the protrusion 170 on the side in contact with the tablet T may be smaller than the area of the bottom surface 170c, and the side surface 170b may have an inclined surface. Further, instead of a quadrangular pyramid, a polygon such as a triangle or a pentagon or a truncated cone may be used. Further, it may have a pyramid shape (pyramid shape, conical shape). The upper surface 170a may be a point, a curved surface, or a spherical surface. When the shape of the protrusion 170 is a cone, the upper surface 170a is a point, but since the tip of the protrusion 170 is easily bent, the shaking of the tablet T is easily attenuated. Further, since the contact with the tablet T by point contact, the powder of the protrusion 170 does not easily adhere to the tablet T. On the other hand, if the upper surface 170a of the protrusion 170 is a flat surface, the internal angle formed by the upper surface 170a and the side surface 170b is an obtuse angle, and if it is a curved surface, the surface where the upper surface 170a and the side surface 170b intersect is an R surface. As a result, the protrusion 170 can be prevented from being scraped or cracked, dust can be prevented from being generated due to the protrusion 170, and the tablet T can be suppressed from shaking as in the case of powder.

In the above-described embodiment, the region having a predetermined width (hatched portion in FIG. 3) including each row of the suction holes 21g of the transport belt 21a is the region (hereinafter referred to as the anti-sway region) Ep on which the tablet T can be placed. However, the protrusion 170 is formed in each of the shaking prevention regions Ep, but the present invention is not limited to this, and for example, the protrusion 170 may be formed to fill the width (conveyor belt width) of the transport belt 21a.

However, when heat is applied to form the protrusion 170 on the surface of the resin transport belt 21a, the heat is applied to the entire width of the transport belt 21a, which may cause deformation such as twisting of the transport belt 21a. be. Therefore, since it is better that the range in which heat is applied is as narrow as possible, it is preferable to provide the protrusion 170 only in the shaking prevention region Ep. Further, when the protrusion 170 is formed only in the shaking prevention region Ep, the area where the protrusion 170 is formed is smaller than that when the protrusion 170 is formed on the entire surface of the transport belt 21a, so that the protrusion 170 is formed. It will be easy. On the other hand, when the protrusion 170 is formed on the entire surface of the transport belt 21a, the place where the tablet T is supplied is loosely limited, and the tablet supply position and the like can be easily adjusted.

In the above-described embodiment, the material of the transport belt 21a is, for example, urethane resin, and the hardness thereof is Hs90. However, if the hardness is higher than Hs50, the material can be applied to the material of the transport belt 21a. When the hardness is Hs50 or less, the durability is inferior. For example, the protrusion 170 is worn away by cleaning the surface of the transport belt 21a by the cleaning device 27, and the effect of suppressing the shaking movement of the tablet T is weakened.

In the above-described embodiment, the tablet T is transported in two rows, but the present invention is not limited to this, and the number of rows may be one row, three rows, or four or more rows, and is particularly limited. It's not a thing.

Further, in the above-described embodiment, it is exemplified that only one transport belt 21a is provided, but the present invention is not limited to this, and two or more conveyor belts 21a may be provided, and the number thereof is not particularly limited. .. For example, it is possible to arrange a plurality of transport belts 21a in parallel.

Further, in the above-described embodiment, it is exemplified that a circular suction hole is used as the suction hole 21g of the transport belt 21a, but the present invention is not limited to this, and a rectangular, elliptical, slit-shaped or other suction hole is used. The shape of the suction hole 21g of the transport belt 21a is not particularly limited.

Further, in the above-described embodiment, it is exemplified that the print head 24a is provided for each transport path of the tablet T, but the present invention is not limited to this, and for example, one print head 24a prints on two or more rows of tablets T. You may try to do.

Further, in the above-described embodiment, as the inkjet type print head 24a, a print head in which the nozzles 24b are arranged in a single row is exemplified, but the present invention is not limited to this, and for example, a print head in which the nozzles 24b are arranged in a plurality of rows is used. You may do so. Further, a plurality of print heads 24a may be used side by side along the transport direction A1 of the tablet T.

Further, in each of the above-described embodiments, the first printing device 20 and the second printing device 30 are arranged one above the other to print on both sides or one side of the tablet T, but the present invention is limited to this. For example, only the first printing device may be provided to print only one side of the tablet T.

Further, in each of the above-described embodiments, it is exemplified that the gas blowing unit 42a is provided in the non-defective product recovery device 42, but the present invention is not limited to this, and for example, the second transfer device 31 in the transfer device 21 is provided. It may be provided at the end on the side or at a place where the tablet T is delivered from the delivery feeder 13 to the transfer device 21. That is, the gas blowing portion 42a may be used at a position where the tablet T is desired to be detached from the transport belt 21a.

Further, in each of the above-described embodiments, it is assumed that the protrusion 170 is simply provided on the surface of the transport belt 21a, but as shown in FIGS. 16 and 17, the transport belt 21a has the tablet T in the transport direction A1. A groove 21h having a predetermined depth extending to the surface may be formed. In this case, suction holes 21g are formed at predetermined intervals at the bottom of the groove 21h. The width of the groove 21h is smaller than the diameter of the tablet T to be transported and larger than the suction hole 21g. The protrusions 170 are formed in a predetermined range on the surface of the transport belt 21a rising from the groove 21h at a predetermined density (see FIG. 16).

In such a transport belt 21a, the tablet T is transported in a state of being placed on the groove 21h without being significantly separated from the groove 21h due to the suction action over the entire groove 21h by the suction from the suction hole 21g. In the process, each tablet T is suppressed from swinging more quickly due to the larger suction action through the groove 21h than when sucking only by the suction hole 21g, and the swinging motion is further suppressed by contacting the protrusion 170. It is suppressed and its swaying motion is more effectively damped.

The protrusions (second protrusions) 180 may also be formed inside the groove 21h (for example, the bottom surface which is the surface of the bottom portion) at a predetermined density (see FIG. 17). When the protrusion 180 is provided inside the groove 21h, as shown in FIG. 17, the height of the upper surface 180a of the protrusion 180 is equal to or less than the height of the upper surface 170a of the protrusion 170 provided outside the groove 21h. The height of the surface of the tablet T on the transport belt 21a side can be set so as to be in contact with the upper surface 180a of the protrusion 180. As a result, even if the diameter of the tablet T is small and the peripheral edge of the tablet T cannot completely contact the upper surface 170a of the protrusion 170 provided on the outside of the groove 21h, the tablet T is brought into contact with the upper surface 180a of the protrusion 180 and stably supported. be able to.

Further, in the above-described embodiment, the height of the bottom surface 171a of the recess 171 is located at a position lower than the height A of the surface of the transport belt 21a outside the region where the protrusion 170 is formed. The height of the bottom surface 171a of the recess 171 and the height A of the surface of the transport belt 21a outside the region where the protrusion 170 is formed may be about the same. Even in this case, the space between the plurality of protrusions 170 and the protrusions 170 can be the recess 171.

Further, in the above-described embodiment, the rotation axis of the rotating brush in the cleaning devices 27 and 37 can be oriented along the row pattern of the protrusions 170 on the surface of the transport belt. For example, as shown in FIG. 5, when the row pattern of the protrusions 170 is in a grid pattern tilted by 45 ° with respect to the transport direction A1, the rotation axis of the rotating brush is tilted by 45 ° in the horizontal plane with respect to the transport direction A1. Alternatively, it is also possible to provide two brushes and incline each rotation axis by + 45 ° and −45 ° in the horizontal plane with respect to the transport direction A1. Further, for example, as shown in FIG. 14, when the row pattern of the protrusions 170 is a row along two axes of an axis parallel to the transport direction A1 and an axis orthogonal to the transport direction A1, the rotation axis of the rotary brush is conveyed. Parallel or orthogonal to direction A1 in the horizontal plane. Further, for example, as shown in FIG. 15, when the protrusions 170 are provided in parallel with the transport direction A1, the rotation axis of the rotating brush is orthogonal to the transport direction A1 in the horizontal plane.

In this way, by making it possible to scrape out the powder in the direction along the row pattern of the protrusions 170, it is possible to more reliably scrape out the powder or the like adhering to the surface of the transport belt 21a. Further, as shown in FIG. 15, when the rotation axis of the rotary brush is tilted at right angles to the transport direction A1, the rotary brush is less likely to be caught by the transport belt 21a by synchronizing the rotation speed of the rotary brush with the tablet transport speed. can do.

Here, the above-mentioned tablets may include tablets used for medicine, food and drink, cleaning, industrial use, or fragrance. In addition, as tablets, there are naked tablets (bare tablets), sugar-coated tablets, film-coated tablets, enteric coated tablets, gelatin-encapsulated tablets, multi-layer tablets, nucleated tablets, etc., and various capsule tablets such as hard capsules and soft capsules are also tablets. Can be included in. Further, as the shape of the tablet, there are various shapes such as a disk shape, a lens shape, a triangle shape, and an ellipse shape. When the tablet to be printed is for pharmaceutical use or food and drink, edible ink is suitable as the ink to be used. As the edible ink, any of synthetic dye ink, natural dye ink, dye ink, and pigment ink may be used.

Although some 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 embodiments, and various omissions, replacements, and changes can be made without departing from the gist of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are also included in the scope of the invention described in the claims and the equivalent scope thereof.

1 Tablet printing device 20 First printing device 21a, 31a Conveyor belt 24a, 34a Printing head 27, 37 Cleaning device 30 Second printing device 50 Control device 170 Protrusion 170a Top 170b Side side 171 Recess 171a Bottom 180 Protrusion T Tablet Ta concave

Claims (9)

A transport belt with a suction hole for sucking tablets,
An inkjet print head that prints on the tablets transported by the transport belt, and
Equipped with
The transport belt is
A plurality of protrusions formed around the suction hole and contact-supporting the tablet,
It has a recess formed between the plurality of protrusions and communicating with the suction hole.
The plurality of protrusions have a frustum in which the area of the individual upper surface of the plurality of protrusions is smaller than the area of the individual bottom surface of the plurality of protrusions, and the individual side surfaces of the plurality of protrusions each have an inclined surface. Has the shape of
The plurality of protrusions are arranged in a row on the surface of the transport belt, and the rows of protrusions are formed so as to be arranged along a direction intersecting the horizontal plane with respect to the transport direction of the tablet.
The plurality of protrusions support the tablet with a gap formed between the surface of the tablet on the transport belt side and the suction hole.
A tablet printing apparatus characterized in that a suction force is applied to the gap and the space of the recess through the suction hole to suck the tablet. The tablet printing apparatus according to claim 1 , wherein the recesses are connected in a row between rows of the protrusions and communicate with the suction holes. The tablet printing apparatus according to claim 1 or 2 , wherein the row of protrusions is provided along two axes orthogonal to each other in a direction inclined at 45 degrees with respect to the transport direction of the tablet. The tablet printing apparatus according to any one of claims 1 to 3 , wherein the outer angle formed by the side surface of the protrusion and the bottom surface of the recess is an obtuse angle. The plurality of protrusions are formed in a region of the transport belt on which the tablet can be placed.
The tablet printing according to any one of claims 1 to 4 , wherein the height of the bottom surface of the recess is lower than the height of the surface of the transport belt outside the region where the plurality of protrusions are formed. Device. The tablet printing apparatus according to any one of claims 1 to 5 , wherein the plurality of protrusions are integrally provided on the transport belt. The tablet to be printed has a recess on the surface and
The tablet printing apparatus according to any one of claims 1 to 6 , wherein the plurality of protrusions contact-support the peripheral edge portion of the tablet on the upper surface or the side surface thereof. The transport belt is provided with a groove extending in the transport direction of the tablet.
The tablet printing apparatus according to any one of claims 1 to 7 , wherein the suction hole is provided on the bottom surface of the groove. The tablet printing apparatus according to claim 8 , wherein a plurality of second protrusions are provided inside the groove.

Images