JP2017006457A - Tablet printing device and tablet printing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a tablet printing device which can quickly suppress the swinging motion of tablets sequentially supplied from the upper side of a conveyor belt and perform printing in high quality.SOLUTION: A tablet printing device comprises: a conveyance mechanism which moves a conveyor belt and conveys tablets sequentially supplied to the surface of the conveyor belt from above the surface; and an ink jet printing mechanism which includes a nozzle head having nozzles jetting ink droplets and arranged so as to face the surface of the conveyor belt, and performs printing to the tablets by jetting the ink from the plurality of nozzles to the tablets on the surface of the conveyor belt, and has such a configuration that minute protrusions 170 are formed with a prescribed density in a region Ep of the surface of the conveyor belt where the tablet can be placed.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a tablet printing apparatus that prints characters, marks, patterns, and the like on the surface of a tablet conveyed by a conveyance belt.

  Conventionally, a solid preparation printing apparatus (tablet printing apparatus) described in Patent Document 1 is known. In this solid preparation printing apparatus, a printing mechanism that performs printing (transfer) using a transfer roller on the surface of a solid preparation that is sequentially conveyed by a conveyor (conveyance belt) prints characters, marks, and the like. In the conveyor, pockets having micro holes formed in the transport direction are arranged, and the solid preparation is sequentially transported by moving the conveyor while the solid preparation is accommodated in the pocket. An air suction portion that sucks air through the micro holes in each pocket is provided on the back side of the portion of the conveyor that faces the transfer roller, and faces the transfer roller of the conveyor by the air suction action of the intake suction portion. A solid preparation contained in each pocket of the portion is fixed in the pocket. Thereby, it transfers (prints) without shifting a character, a mark, etc. to the solid formulation accommodated in each pocket by the transfer roller. And the ink transcribe | transferred on the surface of each solid formulation is dried with the warm air dryer provided in the conveyance direction downstream of the solid formulation of the printing mechanism.

JP-A-6-143539

  By the way, in the tablet printing apparatus which prints on tablets such as solid preparations as in the conventional solid preparation printing apparatus described above, a plurality of nozzles for ejecting ink droplets are provided instead of the printing mechanism using the transfer roller. It is conceivable to use an ink jet printing mechanism (so-called ink jet printer) that has a nozzle head provided and performs printing by ejecting ink droplets from a plurality of nozzles of the nozzle head according to a pattern based on print data. When such an ink jet printing mechanism is used, there is an advantage that even if characters or marks to be printed are changed by changing the type of tablet or the like, it is possible to respond immediately by changing the print data to be provided. Moreover, when the tablet which is a printing object is a thing which is going to be drunk, since it can print non-contact by using an ink ejection printing mechanism, it is hygienic.

  As described above, in the tablet printing apparatus using the ink jet printing mechanism for tablet printing, the tablets are sequentially transported to the printing position by the transport belt. In some cases, tablets are sequentially supplied to the conveyor belt so as to drop from above the surface. The tablets dropped on the surface of the transport belt in this way are transported as the transport belt moves while shaking for a while. In particular, sugar-coated tablets and capsules having a curved surface and a hard surface take a long time from the time they are dropped onto the surface of the conveyor belt until there is no swaying motion. If the swaying movement of the tablet on the surface of the transport belt continues to the printing position, normal printing cannot be performed. For this reason, it is necessary to suppress the swaying motion of the tablet dropped from above the conveyor belt as soon as possible.

  The present invention has been made in view of such circumstances, and provides a tablet printing apparatus that can quickly suppress the shaking movement of tablets supplied to a conveyor belt and can perform high-quality printing.

  The tablet printing apparatus according to the present invention has a transport mechanism having a transport belt for transporting tablets, and a nozzle head having a plurality of nozzles for ejecting ink droplets, and the nozzle head is disposed to face the transport belt. And an ink ejection printing mechanism for performing printing on the tablets by ejecting ink from a plurality of nozzles to the tablets conveyed by the conveyance belt, and in the region where the tablets of the conveyance belt can be placed, The projection is formed at a predetermined density.

  According to such a configuration, the minute protrusion hits the surface of the tablet dropped on the surface of the transport belt, and the shaking of the tablet is suppressed by the minute protrusion.

  The tablet printing method according to the present invention includes a step of supplying a tablet to a transport belt and transporting the tablet by a transport belt, and ejecting ink from a plurality of nozzles to the tablet transported by the transport belt. A step of performing printing on the tablets, and a step of attenuating vibrations of the tablets that occur when the tablets are supplied to the conveyor belt by protrusions formed on the conveyor belt until printing of the tablets is started. It becomes the composition which has.

  According to the present invention, the swaying motion of the tablet supplied to the transport belt is suppressed by the protrusions, so that the swaying motion of the tablet supplied to the transport belt can be quickly suppressed. Thereby, before the printing with respect to a tablet is started, the vibration of the said tablet can be damped and printing with good quality is attained.

It is a figure which shows typically the whole structure of the tablet printing apparatus which concerns on embodiment of this invention. It is a figure explaining the mechanism which adjusts the conveyance belt used for the 1st conveyance mechanism of the tablet printing apparatus shown in FIG. It is a top view which shows the tablet which is conveyed by the shaking prevention area | region of the conveyance belt used for the tablet printing apparatus shown in FIG. 1, and this conveyance belt. It is a top view which shows the example of an arrangement | sequence of the processus | protrusion formed in the shaking prevention area | region of a conveyance belt. It is a figure which shows the state seen from the direction parallel to the conveyance direction of the tablet mounted on the conveyance belt. It is a figure which shows the state seen from the direction orthogonal to the conveyance direction of the tablet mounted on the conveyance belt. It is a figure which shows the state of the tablet which shakes on a conveyance belt. It is a figure which shows the state of the tablet which shakes on the conventional (without protrusion) conveyance belt. It is a figure which shows the state of the tablet conveyed by the other example of a conveyance belt, and this conveyance belt. It is a figure which shows the state of the tablet conveyed by another example of a conveyance belt, and this conveyance belt. It is a figure which shows the state of the tablet which shakes while contacting one protrusion on a conveyance belt. It is a top view which shows the other example of an arrangement | sequence of the protrusion formed in the shaking prevention area | region of a conveyance belt. It is a top view which shows the further another example of arrangement | sequence of the protrusion formed in the shaking prevention area | region of a conveyance belt. It is a top view which shows another example of the conveyance belt used for the tablet printing apparatus shown in FIG. 1, and the tablet conveyed by this conveyance belt. It is a figure which shows the protrusion formed in the conveyance belt shown in FIG. 13, and the tablet conveyed by this conveyance belt. It is a top view which shows the tablet conveyed by the conveyance belt of another structure, and the conveyance belt. It is a figure which shows the conveyance belt of another structure, and the tablet conveyed by the conveyance belt. It is a front view which shows typically the tablet printing apparatus (mechanism part) of the state accommodated in the housing | casing case. It is a side view which shows typically the tablet printing apparatus (mechanism part) of the state accommodated in the housing | casing case.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  The tablet which is the printing object of the tablet printing apparatus according to the present invention will be described by taking the tablet Tb as an example as an example, but the tablet is a bare tablet (uncoated tablet), a sugar-coated tablet, a film-coated tablet (FC tablet) Includes tablets and tablets such as enteric tablets, gelatin-encapsulated tablets, multilayer tablets, and dry-coated tablets, as well as capsule tablets such as hard capsules and soft capsules. For pharmaceutical use, food use, detergent use, industrial use, etc. , Regardless of its use.

  A tablet printing apparatus according to an embodiment of the present invention is configured as shown in FIG. In FIG. 1, a first vibration feeder 12a and a second vibration feeder 12b are continued from a hopper 11 for storing tablets to be printed, and a first delivery feeder 13 and an alignment feeder 14 are further arranged from the second vibration feeder 12b. . A first transport mechanism 17 is disposed behind the alignment feeder 14, and a second delivery feeder 16 is disposed so as to cover the rear end portion of the alignment feeder 14 and the front end portion of the first transport mechanism 17 from above. Yes.

  Each of the first vibration feeder 12a and the second vibration feeder 12b has, for example, a structure in which a vibrator is provided in a bowl-shaped conveyance path, and the tablets Tb sequentially supplied from the hopper 11 are conveyed by vibration. It moves sequentially in the road toward the alignment feeder 14. The alignment feeder 14 has a structure in which alignment guides are arranged on the conveyance path, and the tablets Tb are divided into, for example, two rows by the alignment guide, and the tablets Tb in each row are directed toward the second delivery feeder 16. Convey sequentially. In each of the first delivery feeder 13 and the second delivery feeder 16, a gas permeable conveyance belt is wound around two pulleys (not shown), and an intake chamber coupled to an intake device (not shown) is provided inside the conveyance belt. It has a provided structure. And in the 1st delivery feeder 13, a conveyance belt receives and conveys the tablet Tb from the 1st vibration feeder 12b by the intake action of an intake chamber, and delivers it to the alignment feeder 14 in the position where the intake action of the said intake chamber stops working. . Further, in the second delivery feeder 16, the transport belt receives and transports the tablets Tb from the alignment feeder 14 by the intake action of the intake chamber, and delivers the tablets Tb to the first transport mechanism 17 at a position where the intake action of the intake chamber does not work. .

  The first transport mechanism 17 has a structure in which a transport belt 171 is wound around a drive pulley 172, a tension pulley 173, and two adjustment pulleys 174a and 174b. As will be described later, a through hole 176 is provided in the transport belt 171, and suction air is passed through the through hole 176 to adsorb the tablet Tb to the transport belt 171. The through holes 176 are sequentially formed at a predetermined interval in the moving direction of the transport belt 171 (see FIG. 3). The driving pulley 172 is driven by the motor M, and the annular conveying belt 171 rotates by the rotation of the driving pulley 172 accompanying the driving of the motor M. Further, a first encoder 45 that operates in accordance with the rotation of the drive shaft of the motor M is provided. An intake chamber 175, which will be described later, is provided inside the annular transport belt 171 and connected to an intake device (for example, a vacuum pump) (not shown). Due to the intake action of the intake chamber 175, air is sucked from the back side of the conveyor belt 171, whereby the tablets Tb are adsorbed and held on the surface of the conveyor belt 171 through the through holes 176.

  The intake chamber 175 described above is generally formed in a box shape, and an exhaust port 175a coupled to the intake device is formed at a predetermined portion. Although not shown, the drive pulley 172 is composed of two pulleys arranged in parallel at a predetermined interval in the width direction of the transport belt 171 (the direction from the front to the back of FIG. 1), A box-shaped intake chamber 175 enters between the two pulleys. The intake chamber 175 is formed with a hole through which the shaft of the drive pulley 172 (two pulleys) can rotate while maintaining the airtightness of the intake chamber 175. In the intake chamber 175, the upper portion wall portion (a flat wall portion facing the conveying belt 171 stretched between the drive pulley 172 and the adjustment pulley 174a) and the lower portion wall portion (the drive pulley 172 and A flat wall facing the conveyor belt 171 stretched between the adjustment pulley 174b and a wall on the drive pulley 172 side (between the two pulleys constituting the drive pulley 172 and wound around the drive pulley 172 A plurality of air intake holes (not shown) are formed in each of the wall portions curved in a circular arc shape that are provided between the two pulleys constituting the drive pulley 172 so as to face the conveyor belt 171 that is hung. . The end of the intake chamber 175 opposite to the arcuately curved wall is closed by a wall facing the two adjustment pulleys 174a and 174b.

  Intake in the intake chamber 175 is performed by an intake action of an intake device (not shown) coupled through the exhaust port 175a. As a result, air flows through the intake holes formed in each wall portion of the intake chamber 175 (excluding the wall portions facing the adjustment pulleys 174a and 174b), and further, through the through holes 176 formed in the transport belt 171 as described above. The tablet Tb is adsorbed on the surface of the conveyor belt 171 by being sucked.

  As shown in FIG. 2, the two adjustment pulleys 174a and 174b can move independently in the vertical direction. By adjusting the vertical position of the adjustment pulley 174a, the gap Δa between the upper portion of the conveyor belt 171 and the wall portion of the intake chamber 175 can be adjusted. Further, by adjusting the vertical position of the adjustment pulley 174b, the gap Δb between the lower portion of the conveyor belt 171 and the wall portion of the intake chamber 175 can be adjusted. Further, the tension pulley 173 is movable in the horizontal direction. By adjusting the horizontal position of the tension pulley 173, the tension of the conveyor belt 171 can be adjusted. As described above, the gap Δa between the upper portion of the conveyance belt 171 and the wall portion of the intake chamber 175, the gap Δb between the lower portion of the feed belt 171 and the wall portion of the intake chamber 175, and the conveyance belt 171 Each adjustment of the tension can be easily performed by adjusting the positions of the adjustment pulleys 174a and 174b and the tension pulley 173.

  This tablet printing apparatus has a nozzle head having a plurality of nozzles for ejecting ink droplets, and ejects ink droplets from each nozzle by driving energy generating elements such as piezoelectric elements and thermal elements in accordance with print data. Ink jet printing mechanisms (so-called ink jet printers) that perform printing are used. Around the conveyor belt 171, a nozzle head (referred to as a first nozzle head) 21 of the ink jet printing mechanism, for example, a first tablet sensor 23 composed of a reflective optical sensor, a first posture confirmation camera 24, A first print confirmation camera 25, a first drying unit 27, and two collection trays 28a and 28b are provided. In the intake chamber 175, two air injection nozzles 26a and 26b are provided so as to face the collection trays 28a and 28b with the conveyance belt 171 interposed therebetween.

  As described above, the tablets Tb arranged in two rows by the alignment feeder 14 are supplied to the transport belt 171 of the first transport mechanism 17 through the second delivery feeder 16. In this case, in order to perform printing for each of the two rows of tablets Tb on the transport belt 171, the first nozzle head 21, the first tablet sensor 23, the first posture confirmation camera 24, and the first printing are actually performed. Two sets of the confirmation camera 25, the two air injection nozzles 26a and 26b, the first drying unit 27, and the two collection trays 28a and 28b are provided so as to correspond to the two rows of tablets Tb. Since these two sets perform the same operation, only one set will be described below.

  The first nozzle head 21 (a plurality of nozzles) is disposed to face the surface of the transport belt 171 at the print position Pp. The first tablet sensor 23 detects the tablet Tb on the transport belt 171 at the tablet detection position Pd set at a predetermined upstream position in the moving direction D (the transport direction D of the tablet Tb) of the transport belt 171 at the print position Pp. A detection signal based on the presence or absence is output. The imaging region of the first posture confirmation camera 24 includes a predetermined range between the printing position Pp of the conveyance belt 171 and the tablet detection position Pd. The imaging region of the first print confirmation camera 25 is set to a predetermined range on the downstream side of the print position Pp in the moving direction D of the transport belt 171 (the transport direction D of the tablets Tb). The two air injection nozzles 26a and 26b and the two collection trays 28a and 28b are arranged below the intake chamber 175, that is, with the conveyance belt 171 stretched between the drive pulley 172 and the adjustment pulley 174b interposed therebetween. Has been. A first drying unit 27 is disposed at a predetermined position upstream of the collection trays 28a and 28b so as to face the conveyor belt 171.

  The second transport mechanism 18 has substantially the same structure as that of the first transport mechanism 17 described above. Specifically, in the second transport mechanism 18, the transport belt 181 is wound around a drive pulley 182 driven by a motor M to which the second encoder 46 is attached, a tension pulley 183, and two adjustment pulleys 184a and 184b. An intake chamber 185 is provided which is connected to an intake device (not shown) via an exhaust port 185a inside the conveyor belt 181. Further, similarly to the conveyor belt 171, through holes are formed in the conveyor belt 181 at predetermined intervals in the moving direction of the conveyor belt 181. The tablet Tb is adsorbed and held on the transport belt 181 by suction of air through the through-hole due to the intake action of the intake chamber 185 based on the operation of the intake device (not shown). Around the transport belt 181, the second nozzle head 31 (print position Pp), the second tablet sensor 33 (tablet detection position Pd), the second posture confirmation camera 34, the second print confirmation camera 35 of the ink jet printing mechanism, A second drying unit 37 and two collection trays 38a and 38b are provided. In the suction chamber 185, two air injection nozzles 36a and 36b are disposed so as to face the two collection trays 38a and 38b with the conveyance belt 181 interposed therebetween. In particular, in the second transport mechanism 18, the storage tray 40 is disposed to face the most downstream portion in the moving direction D of the transport belt 181 (the transport direction D of the tablets Tb).

  In the tablet printing apparatus having the above-described structure, characters and marks are sequentially printed on the surface of the tablet Tb as follows under the control of the print control unit 100.

  As described above, the tablets Tb sequentially supplied from the hopper 11 and moving through the first vibration feeder 12 a and the second vibration feeder 12 b are delivered to the alignment feeder 14 by the first delivery feeder 13. Then, for example, the tablets Tb arranged in two rows are sequentially delivered to the first transport mechanism 17 by the second delivery feeder 16 by the alignment feeder 14. The tablets Tb sequentially delivered to the first transport mechanism 17 by the second delivery feeder 16 are sequentially transported in two rows while being attracted and held on the transport belt 171.

  If the tablet Tb (located at the tablet detection position Pd) is detected on the basis of the detection signal from the first tablet sensor 23 in the process of transporting the tablets Tb in each row in the first transport mechanism 17, thereafter. Based on the value of the first encoder 45, the print control unit 100 recognizes the detected position of the tablet Tb with the tablet detection position Pd as a base point. When the tablet Tb enters the imaging region of the first posture confirmation camera 24, the first posture confirmation camera 24 takes a picture of a predetermined photographing range. Based on this photographed image, the tablet Tb is damaged, such as dirt or chips. Further, the posture of the tablet Tb determined to be undamaged on the transport belt 171 (front and back of the tablet Tb, position on the belt, orientation held on the belt, and vertical direction) (Including postures such as the inclination of). After that, when the tablet Tb determined not to be damaged passes through the printing position Pp, the first nozzle is printed in accordance with the print data generated based on the information (determination result) on the detected damage and posture of the tablet Tb. The ejection pattern of ink droplets from the plurality of nozzles of the head 21 is controlled, and characters, marks, and the like are printed at predetermined positions on the surface of the tablet Tb in a predetermined direction. At this time, printing is not performed for the tablet Tb determined to be damaged. That is, print data indicating that printing is not performed is generated. Thereafter, the print control unit 100 tracks the position of the tablet Tb that has not been printed (based on the value of the first encoder 45).

  Further, when the tablet Tb that has undergone printing (printing position Pp) enters the imaging area of the first printing confirmation camera 25, the first printing confirmation camera 25 captures an image of a predetermined imaging range, and based on this captured image, the tablet Tb It is determined whether or not characters or marks are normally printed. Thereafter, the print control unit 100 tracks the position of the tablet Tb (based on the value of the first encoder 45) determined to have not been printed normally.

  The tablet Tb that has completed printing and has passed through the imaging region of the first print confirmation camera 25 is transported as the transport belt 171 moves, and is printed on the surface when transported opposite the first drying unit 27. The printed character or mark ink is dried (fixed). When the tablet Tb whose position is tracked by the print control unit 100 without being printed due to damage such as chipping or the like reaches a position facing one of the air injection nozzles 26a, the air injected from the air injection nozzle 26a. As a result, the toner is ejected from the conveyor belt 171 and collected in the collection tray 28a. Further, although there is no damage such as chipping, when the tablet Tb whose position is being tracked by the print control unit 100 without being printed normally reaches the position facing the other air injection nozzle 26b, the air injection is performed. The air is ejected from the conveying belt 171 by the air ejected from the nozzle 26b and is collected on the other collection tray 28b.

  The tablet Tb on which characters and marks are normally printed on the surface is transported as the transport belt 171 moves, and transported by the second transport mechanism 18 from the transport belt 171 at a position where the suction action of the suction chamber 175 stops working. It falls on the belt 181. In this way, the tablets Tb that are normally printed on the surface are transferred from the first transport mechanism 17 to the second transport mechanism 18. That is, it is delivered in a state where the printed surface is turned upside down so as to be on the conveying belt 181 side.

  Also in the second transport mechanism 18, as in the case of the first transport mechanism 17, the second tablet sensor of the tablets Tb sequentially transported as the transport belt 181 moves under the control of the print control unit 100. Position tracking based on the value of the second encoder 46 based on the output timing of the detection signal 33 (tablet detection position Pd), the back surface of each tablet Tb (surface opposite to the surface printed by the first transport mechanism 17) Printing of characters, marks and the like by the second nozzle head 31 (positioned at the printing position Pp), drying of ink of characters and marks printed on the tablets by the second drying unit 37, and damaged tablets by the air injection nozzle 36a Recovery of Tb to the recovery tray 38a and recovery of the poorly printed tablet Tb to the recovery tray 38b by the air injection nozzle 36b are performed. Then, the tablet Tb printed normally is dropped and stored in the storage tray 40 at a position where the suction action of the suction chamber 185 does not work.

  In the tablet printing apparatus described above, for example, the tablets Tb are sequentially dropped from the second delivery feeder 16 disposed above the transport belt 171 of the first transport mechanism 17 onto the surface of the transport belt 171 of the first transport mechanism 17. Each tablet Tb dropped on the surface of the moving conveyor belt 171 is conveyed toward the detection position Pd by the movement of the conveyor belt 171 while shaking. In order to suppress the shaking movement of the tablet Tb, minute protrusions are formed on the surface of the transport belt 171.

  Specifically, as shown in FIG. 3, the tablet Tb is adsorbed on the conveyor belt 171 by sucking air by the intake action of the intake chamber 175 as described above at a predetermined interval in the moving direction of the conveyor belt 171. Two rows of through holes 176 are formed. Then, assuming that each region (shaded portion) having a predetermined width including each row of the through holes 176 of the transport belt 171 is a region where the tablet Tb can be placed (hereinafter referred to as a “sway prevention region”) Ep, each of the shake prevention regions. Small protrusions are formed at a predetermined density on Ep. For example, as shown in FIG. 4, the minute protrusions 170 are formed at a density of three or more with respect to the area ETb covered by the tablet Tb. For example, in the case of a tablet Tb having a diameter (maximum diameter) of about 10 mm, the projections 170 having a size (maximum diameter) of 1 mm are arranged in a plane in each shaking prevention region Ep at intervals of 2 mm. Further, the height of each protrusion 170 is set in a range of 1/20 or more and 1/5 or less of the thickness (maximum thickness) of the tablet Tb, and preferably the thickness (maximum thickness) of the tablet Tb. It is set to 1/10.

  As will be described later, in order for the protrusion 170 to be a contact or fulcrum for suppressing the shaking movement of the tablet Tb, depending on the shape of the surface of the tablet Tb, the surface roughness level (about several tens of μm) of the transport belt 171 is not used. A height of at least 100 μm is required. Further, it is assumed that the tablet Tb is in contact with not only the protrusion 170 but also the surface of the conveyance belt 171 without the protrusion 170, or is supported by the protrusion 170 having a different height and inclined with respect to the conveyance belt 171. However, if it is 1/5 or less of the thickness of tablet Tb, it will not become a printing defect by the inclination. In addition, the diameter (maximum diameter) of the tablet Tb is approximately 5 to 12 mm, and the thickness (maximum thickness) is 2 to 8 mm.

    The protrusion 170 is preferably formed of a material that is more flexible than the material of the conveyor belt 171 (for example, urethane), such as silicon rubber. For example, the material of the conveyance belt 171 is about hardness (rubber hardness, Shore A) Hs90, and the protrusion 170 is made of silicon and the hardness is about Hs50. Various combinations of materials can be applied, but the hardness of the conveyor belt 171 may be selected in the range of Hs 60 to 120, and the protrusion 170 may be selected in the range of Hs 20 to 80. However, the hardness of the protrusion is lower than that of the conveyor belt. Further, when different materials are bonded as described above to form the protrusions, it is possible to select materials having good bonding properties (adhesiveness). The flexibility can be expressed by, for example, an elastic modulus, a deformation rate, and the like. The large flexibility includes a large elastic modulus and a large deformation rate. Moreover, flexibility can also be enlarged by the shape like elongate shape like the hair of a brush, for example.

  In the conveyance belt 171 (swing prevention region Ep) on which the protrusions 170 are formed as described above, for example, as shown in FIGS. 5A and 5B, the tablet Tb comes into contact with and supports the plurality of protrusions 170. .

  FIG. 5A is a schematic view of the state where the tablet Tb is placed on the transport belt 171 as viewed from the side of the tablet Tb (viewed from a direction parallel to the transport direction D), and from the back to the front with respect to the paper surface. The state being conveyed is shown. That is, the horizontal direction in the figure is the width direction of the conveyor belt 171. FIG. 5B is a view (as viewed from the direction orthogonal to the transport direction D) of the side surface on which the tablet Tb is transported from the left to the right of the page. That is, the left-right direction in the figure is the conveyance direction D. In the example shown in FIG. 5A and FIG. 5B, the projections 170 are in contact with and supported by three points. In addition, the figure which shows the contact of subsequent protrusions and a tablet is the figure which looked at the state by which the tablet Tb is mounted on the conveyance belt 171 from the side surface of the tablet Tb, and showed the state in an easy-to-understand manner However, not all protrusions are shown. Further, unless otherwise indicated, a state where the paper is conveyed from the back to the front with respect to the paper surface is shown.

  As shown in FIG. 6, the tablet Tb in contact with the plurality of protrusions 170 swings in a state of being in contact with the plurality of protrusions 170. For this reason, as shown in FIG. 7, especially when the surface of the tablet Tb is a spherical surface, a cylindrical curved surface, or the like, the tablet Tb freely swings on the surface of the transport belt 171 without the protrusions 170, so that the swinging movement is difficult to be suppressed. On the other hand, since the tablets Tb are supported at multiple points by the protrusions 170 that dispersively hit the surface of the tablet Tb, the swaying movement is easily hindered. That is, it becomes support at a plurality of points at a certain interval, and the vibration of the tablet Tb is easily attenuated by restricting the free vibration. Furthermore, since each protrusion 170 is made of a material such as silicon rubber having a higher flexibility than the material of the conveyor belt 171, or is formed in a shape having a high flexibility, it serves as a damper. Further, the swaying motion can be absorbed more, and coupled with the effect of suppressing the swaying motion by contacting the plurality of protrusions 170, the swaying motion of the tablet Tb can be effectively attenuated and suppressed. It should be noted that vibration when supplied onto the conveyor belt 171 occurs even if the surface of the tablet Tb is not a spherical surface or a cylindrical curved surface. It is clear that the same effect can be obtained even if the tablet surface is flat.

  Therefore, the shaking movement of the tablets Tb sequentially supplied from the second delivery feeder 16 positioned above the conveyor belt 171 to the conveyor belt 171 can be quickly suppressed. As a result, each tablet Tb transported by the transport belt 171 can pass through the position detection position Pd and the printing position Pp without shaking, and the position and orientation of each tablet Tb can be accurately detected. Good printing is possible.

  In the above-described example, the protrusions 170 formed in the shaking prevention region Ep of the transport belt 171 have the same height. However, as shown in FIG. 8, all the protrusions 170 have the same height. Not necessarily. Moreover, as shown in FIG. 9, you may make it form the protrusion 170 with the density of one in the area ETb which the tablet Tb covers in the shaking prevention area | region Ep. Even in these cases, as in the above-described example (see FIG. 6), the shaking tablet Tb can come into contact with the protrusion 170 to attenuate the shaking movement. If there is at least one contact of the tablet Tb in addition to the surface of the transport belt 171, the swing in the direction connecting the two contact points is suppressed. As a result, the energy of the shaking motion is attenuated, and the shaking motion other than the direction between the contact points is suppressed. However, as in the example described above, when the protrusions 170 are formed in the area ETb covered by the tablet Tb with a density of 3 or more, the shaking movement of each tablet Tb is attenuated more quickly than in the case of the same density. Can do.

  In particular, as shown in FIG. 10, even when the contact point with the protrusion 170 does not become the support point of the tablet Tb and the tablet Tb swings on the surface without the protrusion 170 of the transport belt 171, the side where the protrusion 170 is present. The swinging angle Δθ2 toward the side where the protrusion 170 is present is smaller than the swinging angle Δθ1 toward the side where the protrusion 170 is not present. Thereby, the balance of the shaking movement of the tablet Tb is disturbed, the energy of the shaking movement of the tablet Tb is attenuated, and the shaking movement is suppressed.

  Such an action is the same even if the surface is a cylindrical curved surface like a capsule tablet.

  Further, the protrusions 170 may not be arranged in an orderly manner as shown in FIG. For example, as illustrated in FIG. 11, the protrusions 170 may be randomly arranged at a predetermined density. Moreover, the shape of each protrusion 170 is not the same, for example, as shown in FIG. 12, various shapes of protrusions 170 (1), 170 (2), 170 (3), 170 (5), 170 (6 ) May be formed in the shaking prevention region Ep. Even in these cases, as in the above-described example (see FIG. 6), the shaking tablet Tb can come into contact with the protrusion 170 to attenuate the shaking movement.

  Further, in the above-described example, the protrusion 170 is formed only in the shaking prevention region Ep determined as a region where the tablet Tb of the transport belt 171 can be placed, but the invention is not limited thereto. The protrusions may be formed on the entire surface of the conveyor belt 171 with a predetermined density. When the protrusion 170 is formed only in the shaking prevention region Ep, the area for forming the protrusion is reduced, so that the formation of the protrusion 170 is facilitated. On the other hand, in the case where the protrusions 170 are formed on the entire surface of the transport belt 11, the limitation on the place where the tablet Tb is supplied becomes moderate, and the adjustment of the tablet supply position and the like can be easily performed.

  In order to verify the effect of suppressing the shaking movement, a silicone agent having a rubber hardness of Hs50 is applied to the entire surface of the conveyance belt to which tablets are supplied with a urethane conveyance belt having a width of 15 mm and a rubber hardness of Hs90. A belt with a protrusion was prepared by forming a protrusion having a height of ˜3 mm and a height of 1 to 2 mm at random by pressing a round frame mold and then completely curing the protrusion. A sugar-coated tablet having a curved surface with a diameter of φ10 mm and a thickness of 6.6 mm is supplied and transported on the transport belt with projections, and the time from when the tablet is fed onto the transport belt until the shaking motion is settled to a predetermined value is set. Observed with a high-speed camera. As a result, when there was no projection, it took about 2145 ms for the swing motion to converge to a predetermined value, whereas when the projection was present, the swing motion converged to the predetermined value in about 33 ms. Thereby, it was confirmed that the shaking motion of the tablet was suppressed in about 1/60 time due to the presence of the protrusion.

  Further, since the tablet printing apparatus described above uses the intake chamber 175 that is sucked through the exhaust port 175a having a relatively large opening, the suction efficiency is good and the suction force for each tablet Tb can be increased. For this reason, the holding force of each tablet Tb to the transport belt 171 is increased, so that more stable transport can be performed, and the vibration of each tablet Tb can be attenuated more quickly. Further, by adjusting the positions of the adjustment pulleys 174a and 174b (see FIG. 2), the gap between the intake chamber 175 and the transport belt 171 can be set appropriately, so that the suction force for each tablet Tb can be increased. . Therefore, similarly to the above, the holding force of each tablet Tb to the transport belt 171 becomes stronger, more stable transport can be performed, and the vibration of each tablet Tb can be attenuated more quickly.

  In the example described above, the tablets Tb are supplied in two rows to the transport belt 171 (181) (see FIG. 3), but this is not restrictive. The tablets Tb may be supplied to the transport belt 171 (181) in one row or three or more rows. Further, a plurality of conveyor belts may be arranged in parallel, and the tablets Tb may be supplied to each conveyor belt in one row. In particular, when the tablets Tb are conveyed in a plurality of rows, the nozzle head 21, the cameras 23 and 25, the drying unit 27, and the recovery mechanism (28a, 28b, 40) are shared by the plurality of rows of tablets Tb. You can also

  As the above-described transport belt 171 (181), a transport belt having the structure shown in FIGS. 13 and 14 can be used.

  As shown in FIGS. 13 and 14, the conveyor belt 171 is formed with a groove 177 having a predetermined depth extending in the moving direction of the conveyor belt 171. And the through-hole 176 is formed in the bottom part of the groove | channel 177 at predetermined intervals. The width of the groove 177 is smaller than the diameter of the transported tablet Tb. The protrusions 170 are formed at a predetermined density in a predetermined range on the surface of the conveyor belt 171 rising from the groove 177 (see FIG. 14).

  In such a conveyor belt 171, the tablets Tb that are sequentially dropped from the second delivery feeder 16 toward the groove 177 of the conveyor belt 171 oscillate, and the groove 177 is moved by the intake action over the entire groove 177 by the intake air from the through hole 176. It is transported in a state where it is placed on the groove 177 without greatly leaving. In the process, each tablet Tb is restrained from shaking more rapidly by a larger intake action through the groove 177 than when only sucking through the through-hole 176, and is further restrained by contacting the protrusion 170. And the shaking movement is attenuated more effectively.

  In the tablet printing apparatus described above, a timing belt with teeth is used as the transport belt 171, and timing pulleys are used as the drive pulley 172 and the tension pulley 174. Thereby, the slip of the conveyance belt 171 can be reduced as much as possible, and the position of each tablet Tb on the conveyance belt 171 can be accurately tracked based on the output value of the first encoder 45.

  A flat belt can be used as the transport belt 171. In this case, for example, as shown in FIG. 15, holes 178 are formed in the edge portion of the conveyor belt 171 (flat belt) so as to be arranged at a predetermined interval in the longitudinal direction (moving direction). A light emitting element and a light receiving element are provided so as to sandwich the row of the holes 178. When the transport belt 171 moves, the light from the light emitting element that passes through each hole 178 is detected by the light receiving element, and the number of holes 178 is counted based on the detection signal from the light receiving element, and the count value The amount of movement of the conveyor belt 171 is calculated based on the above. In this way, even if slip occurs on the conveyor belt 171 (flat belt) wound around the drive pulley or the driven pulley, the slippage does not depend on the output value of the first encoder 45, so the accurate movement of the conveyor belt 171 is achieved. The amount can be detected.

  In addition, you may make it form the hole 178b from which a shape differs (for example, large) for every predetermined number of the holes 178a of the normal shape arranged. In this way, the counter can be prevented from overflowing by resetting the counter each time the hole 178b having a different shape is detected.

  Further, as shown in FIG. 16, a mark 179 may be formed on the surface portion of the transport belt 171 (flat belt) in the thickness direction. In this case, the reflection type optical sensor is arranged so as to face the surface of the transport belt 171 in the thickness direction. When the conveyance belt 171 moves, the marks 179 are sequentially detected by the optical sensor, the number of the marks 179 is counted based on the detection signal, and the movement amount of the conveyance belt 171 is calculated based on the count value. In this way, even if a slip occurs on the transport belt 171 (flat belt) wound around the drive pulley or the driven pulley, an accurate movement amount of the transport belt 171 can be detected.

  Also in this case, a mark 179b having a different shape (for example, a large size) may be formed for each predetermined number of normal-shaped marks 179a arranged. In this way, it is possible to prevent the counter from overflowing by resetting the counter each time the mark 179b having a different shape is detected.

  Compared to the timing belt, the flat belt has many kinds of materials, and it is easy to select a material on which the protrusion 170 can be easily formed. In the above example, the hardness of the protrusion 170 is lower than the hardness of the conveyor belt 171 and is flexible. However, since the flat belt has a wide range of material options, a protrusion with high flexibility that suppresses the shaking movement of the tablet is used. It is also easy to use a material that can be integrally formed with the same material as the conveyor belt. In this way, the cost for forming the protrusion can be reduced.

  In each example described above, the surface layer of the conveyor belt 171 may be formed of a highly flexible material, like the protrusions 170.

  Further, in the tablet printing apparatus shown in FIG. 1, protrusions 170 are formed on the surface of the transport belt 181 of the second transport mechanism 18 in the same manner as the transport belt 171 of the first transport mechanism 17 described above. In addition, the present invention is not limited to this, and if the transport belt is supplied such that the tablets are dropped from above like the transport belt of the alignment feeder 14, similarly, by forming minute protrusions, It can be suppressed quickly.

  As the conveyor belts 171 and 181, a conveyor belt formed in a mesh shape and having gas permeability can be used.

  The tablet printing apparatus (mechanism part) described above is housed in a housing case 200 as shown in FIGS. 17 and 18. FIG. 17 is a front view schematically showing the tablet printing device housed in the housing case 200, and FIG. 18 is a side view schematically showing the tablet printing device housed in the housing case 200. is there. In addition, FIG. 17 is an AA arrow view of FIG.

  17 and 18, the tablet printing apparatus having the above-described structure (the same structure as FIG. 1) is housed in a generally box-shaped housing case 200. Each mechanism such as the alignment feeder 14, the second delivery feeder 16, the first transport mechanism 17, and the second transport mechanism 18 is disposed at a location relatively close to the front wall portion of the housing case 200, and the first transport mechanism 17. The first intake pipe 207 that connects the suction chamber 175 to the intake device (not shown) and the second intake pipe 208 that connects the intake chamber 185 of the second transport mechanism 18 to the intake device (not shown) are respectively in the housing. It extends to the back of the case 200. A transparent window 202 is fitted into a predetermined portion of the front wall portion of the case 200 so that the operator OPT can see the inside of the case 200 through the window 202.

  Thus, in a state where each mechanism of the tablet printing apparatus is housed in the housing case 200, the operator OPT passes through the window body 202 to each mechanism (the first transport mechanism 17, the second transport mechanism 18, etc.) and its mechanism. I can't see the back side directly. For this reason, it has been necessary to stop the tablet printing apparatus, remove the front cover of the housing case 200, and inspect the inside (the surrounding area of each mechanism). Therefore, not only the workability is bad, but also the state of each mechanism, the state of the tablets to be conveyed, and the back side portion of each mechanism could not be visually inspected while the tablet printing apparatus is operating. .

  In consideration of such points, as shown in FIGS. 17 and 18, a mirror plate 210 inclined obliquely upward is provided in the housing case 200 so as to face the window body 202. Thus, by providing the mirror surface plate 210, the operator OPT outside the housing case 200 passes through the window body 202 and each mechanism (the first transport mechanism 17, the second transport mechanism 18, etc.) reflected on the mirror surface plate 210. You can see the state of the tablet, the back side, and the state of the tablet transport. For this reason, the operator OPT can easily visually check whether each mechanism has a problem while operating the tablet printing apparatus without stopping.

  As mentioned above, although embodiment of this invention and the modification of each part were demonstrated, this embodiment and the modification of each part are shown as an example, and are not intending limiting the range of invention. These novel embodiments described above can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the spirit of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention and included in the invention described in the claims.

DESCRIPTION OF SYMBOLS 11 Hopper 12a 1st vibration feeder 12b 2nd vibration feeder 13 1st delivery feeder 14 Alignment feeder 16 2nd delivery feeder 17 1st conveyance mechanism 170 Protrusion 171 Conveyance belt 172 Drive pulley 173 Tension pulley 174a, 174b Adjustment pulley 175 Intake chamber 176 Through hole 177 Groove 178 Hole 179 Mark 18 Second transport mechanism 181 Transport belt 182 Drive pulley 183 Tension pulley 184a, 184b Adjustment pulley 185 Intake chamber 21 First nozzle head 23 First tablet sensor 24 First posture confirmation camera 25 First print Confirmation camera 26a, 26b Air injection nozzle 27 First drying unit 28a, 28b Collection tray 31 Second nozzle head 33 Second tablet sensor 34 Second posture confirmation camera 35 First 2 Print confirmation camera 36a, 36b Air injection nozzle 37 Second drying unit 38a, 38b Collection tray 40 Storage tray 45 First encoder 46 Second encoder 100 Print control unit 200 Housing case 202 Window body 207 First intake pipe 208 Second Intake pipe 210 Mirror plate

Claims (5)

A transport mechanism having a transport belt for transporting tablets;
A nozzle head having a plurality of nozzles for ejecting ink droplets, the nozzle head being disposed opposite to the transport belt, and ejecting ink from the plurality of nozzles to a tablet transported by the transport belt; An ink jet printing mechanism for performing printing on the tablet,
A tablet printing apparatus in which protrusions are formed at a predetermined density in an area where the tablets of the transport belt can be placed.   The tablet printing apparatus according to claim 1, wherein the protrusion is formed at a density of at least one with respect to an area covered by the tablet.   The tablet printing apparatus according to claim 1 or 2, wherein a height of the protrusion is in a range of 1/20 or more and 1/5 or less of the thickness of the tablet.   The tablet printing apparatus according to claim 1, wherein the protrusion is formed of a material that is more flexible than a material of the transport belt. Supplying tablets to the conveyor belt, and transporting the tablets with the conveyor belt;
A step of performing printing on the tablets by ejecting ink from a plurality of nozzles to the tablets conveyed by the conveyance belt;
A tablet printing method comprising: attenuating vibration of the tablet that occurs when the tablet is supplied to the conveyor belt by a protrusion formed on the conveyor belt until printing of the tablet is started.

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