Tablet printer and tablet printing method

Abstract

To suppress tablet misalignment or inclination on a conveyance path during transfer of a tablet from an upstream conveyance part to a downstream conveyance part.SOLUTION: A tablet printer comprises reversal means 5T positioned above upstream conveyance means 3 and adapted to hold a tablet T conveyed by the upstream conveyance means with a lower surface facing a conveyance surface and reverse the table T in an opposite second direction D2 from a first direction D1. The reversal means has a rotary drum 52 having a plurality of suction ports 52a opened on a circumferential surface and configured to be capable of executing sucking through the suction port within a prescribed rotation angle range. The rotary drum starts suction when the suction port is directed in a prescribed direction in a boundary region BR along with rotation, thereby sucking an upward surface of the tablet T conveyed by the upstream conveyance means 3 to adsorb and hold the tablet T above the circumferential surface, and adsorbs and hold the tablet T during rotation within the prescribed rotation angle range, and conveys it to downstream linear conveyance means 5L.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a tablet printing device that prints predetermined information on the front and back surfaces of tablets. [Background technology]

[0002] In recent years, tablet printing devices are used in the manufacturing processes of medicines, foods, confectioneries, etc., to print identification information such as letters, figures, and images representing company names and product names on tablets. This tablet printing device requires the handling of a large number of tablets in order to print information on their front and back surfaces.

[0003] Fig. 34 shows an example of the configuration of a conventional tablet printing device 1X described in Patent Document 1, and Fig. 35 is a schematic front view showing the operation. In the conventional tablet printing device 1X, for example, as shown in Fig. 34, the tablet T received from the supply unit 2X is linearly conveyed in one direction (arrow T1X in Fig. 34), and then adsorbed and held by the rotary suction conveying means 31X to invert the tablet T (arrow T2X in Fig. 34), an upstream printing unit 4X that prints predetermined information on one of the upper surfaces of the front and back surfaces of the tablets T, a downstream conveying unit 5X that is disposed below the upstream conveying unit 3X and receives the tablet T from the upstream conveying unit 3X in an inverted state and linearly conveys the tablet T in the opposite direction to the upstream conveying unit 3X (arrow T3X in Fig. 34), a downstream printing unit 6X that prints predetermined information on the other surface of the tablet T, and a discharge unit 7X that discharges the tablet T after printing out of the system (arrow T4X in Fig. 34). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2017-200495 A Summary of the Invention [Problem to be solved by the invention]

[0005] However, in the conventional tablet printing device 1X described in Patent Document 1, as shown in FIG. 35, when the tablet T that has been turned upside down is transferred from the upstream conveying section 3X to the downstream conveying section 5X, the tablet T may be pulled back backward by the negative pressure P from the upstream side in the conveying direction (arrow M1 in FIG. 35). This phenomenon is caused by the negative pressure P being applied to the falling tablet T from the upstream side in the rotation direction, since the tablet T is dropped from the peripheral surface of the upper rotary suction conveying means 31X onto the lower downstream conveying section 5X by releasing the suction of the tablet T at the position TP where the conveying surface of the upstream conveying section 3X faces downward. In this case, the position of the tablet T may be shifted on the conveying path, causing printing defects in the downstream printing section 6X. Alternatively, the tablet T may be tilted, causing a problem in which the tilted tablet T is caught in the gap between the rotary suction conveying means 31X and the downstream conveying section 5X.

[0006] The present disclosure has been made in consideration of the above-mentioned problems, and aims to provide a tablet printing device and a tablet printing method that can suppress positional misalignment and tilt of tablets on the conveying path during the tablet transfer process between the upstream conveying section and the downstream conveying section. [Means for solving the problem]

[0007] A tablet printing method according to one aspect of the present disclosure is a tablet printing device that prints information on the front and back surfaces of a tablet transported along a transport path, the tablet printing device including: an upstream transport means that holds the tablet with one of the front and back surfaces of the tablet facing downward facing a transport surface and transports the tablet in a first direction; an upstream printing unit that prints information on the other of the front and back surfaces of the tablet that faces upward while the tablet is being transported by the upstream transport means; downstream transport means that is located above the upstream transport means and holds the tablet transported by the upstream transport means with the other surface facing opposite the transport surface and flips the tablet from the first direction to a second direction opposite to the first direction; and downstream linear transport means that transports the tablet in the second direction. and a downstream printing unit which prints information on one side of the tablet being transported by the upstream conveying means, the upstream conveying means and the inversion means are arranged facing each other with their respective conveying surfaces separated by a predetermined distance at their boundary area on the conveying path, the inversion means has a suction means having an air intake port which faces the conveying surface of the upstream conveying means at the boundary area, the suction means sucks in the other side of the tablet on the conveying surface of the upstream conveying means to adsorb and hold the tablet on the conveying surface of the downstream conveying means, thereby transferring the tablet from the upstream conveying means to the downstream conveying means, and the predetermined distance is configured to be adjustable by changing the position of the downstream conveying means and / or the upstream conveying means. Effect of the Invention

[0008] According to one aspect of the present disclosure, a tablet printing device and a tablet printing method can be provided that can suppress positional misalignment and tilt of tablets on the conveying path during the process of transferring tablets from an upstream conveying section to a downstream conveying section. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a front view showing an outline of the configuration of a tablet printing apparatus 1A according to a first embodiment. [Diagram 2]FIG. 1 is a perspective view showing a schematic configuration of a tablet printing apparatus 1A. [Diagram 3] 1A is a plan view of the conveyor belt, FIG. 1B is a side view, and FIG. 1C is a cross-sectional view of the conveyor belt taken along line A1-A1 in FIG. [Figure 4] 1A is a front cross-sectional view of a main portion of the reversing means 5T related to conveyance, and FIG. 1B is a cross-sectional view of the reversing means 5T taken along line A2-A2 in FIG. [Diagram 5] 1A is a schematic cross-sectional view illustrating a tablet delivery operation from an upstream conveying means to a downstream conveying means in the tablet printing apparatus 1A. FIG. [Figure 6] FIG. 11 is a front view showing an outline of the configuration of a tablet printing apparatus 1B according to a second embodiment. [Figure 7] 3A is a front cross-sectional view of a main portion of the reversing means 5TB relating to conveyance, and FIG. 3B is a cross-sectional view of the reversing means 5TB taken along line A3-A3 in FIG. [Figure 8] 7(a) showing the reversing means 5TB. FIG. [Figure 9] FIG. 11 is a front view showing the outline of the configuration of a tablet printing apparatus 1C according to embodiment 3. [Figure 10] 4A is a front cross-sectional view of a main portion of the reversing means 5TC related to conveyance, and FIG. 4B is a cross-sectional view of the reversing means 5TC taken along line A4-A4 in FIG. [Figure 11] 10(a) showing the reversing means 5TC. FIG. [Figure 12] 10(b) showing the reversing means 5TC. FIG. [Figure 13] FIG. 11 is a front view showing the outline of the configuration of a tablet printing apparatus 1D according to embodiment 4. [Figure 14] 1 is a plan view of a tablet supply unit 2D, an upstream printing unit 4U, and a discharging and conveying means 9 in a tablet printing apparatus 1D. [Figure 15] 14 is a cross-sectional view of the tablet printing apparatus 1D taken along line A5-A5 in FIG. 13. [Figure 16] FIG. 16 is a flowchart showing an outline of the conveying speed adjustment operation in the tablet printing apparatus 1D. [Figure 17] 6(a) is a plan view showing an outline of the configuration of a tablet supplying unit 2E in a tablet printing apparatus 1E of embodiment 5, and (b) is a cross-sectional view of the tablet supplying unit 2E taken along line A6-A6 in (a). [Figure 18] 13(a) and (b) are diagrams for explaining an outline of the selective discharge operation of abnormal tablets in the tablet supplying section 2E. [Figure 19] 13(a) and (b) are diagrams for explaining an outline of the discharge operation of accumulated tablets by a first mode of a tablet supplying section 2E. [Figure 20] 13(a) and (b) are diagrams for explaining an outline of the discharge operation of accumulated tablets by a second mode of the tablet supplying section 2E. [Figure 21] 13(a) and (b) are diagrams for explaining an outline of the discharge operation of accumulated tablets according to a third embodiment of the tablet supplying section 2E. [Figure 22] 13 is a flowchart showing an outline of the selective ejection operation of abnormal tablets related to the supply in the tablet printing apparatus 1E. [Figure 23] 13 is a flowchart showing an outline of a maintenance operation in the tablet supplying section 2E. [Figure 24] 13 is a flowchart showing an outline of a selective front / back discharge operation related to supply in a modified example of the tablet printing apparatus 1E. [Diagram 25] FIG. 13 is a plan view showing an alternative configuration of the upstream printing unit 14U or the downstream printing unit 14D in the tablet printing device 1F of embodiment 6, where (a) is an overview of normal operation and (b) is an overview of maintenance operation. [Figure 26] 25(a) and (b) are cross-sectional views of the upstream printing unit 14U and the downstream printing unit 14D in the tablet printing apparatus 1F taken along lines A13-A13 and A14-A14 in Figures 25(a) and (b), respectively. [Figure 27] 11 is a flowchart showing an outline of a maintenance operation in the tablet printing apparatus 1F. [Figure 28] FIG. 13 is a plan view showing an outline of the configuration of a print defect sorting section 220 in a tablet printing apparatus 1G according to embodiment 7. [Figure 29] 2 is a front view showing an outline of the configuration of a print defect sorting unit 220. FIG. [Diagram 30] 29 is a cross-sectional view of the print defect sorting unit 220 taken along line A15-A15 in FIG. 28. [Diagram 31] 13 is a plan view illustrating the tablet discharge operation related to a printing defect in the tablet printing apparatus 1G. FIG. [Diagram 32] 13 is a flowchart showing an overview of the analysis and recording operation of tablet discharge related to printing defects in the tablet printing device 1G. [Diagram 33] 13 is a flowchart showing an outline of the adjustment operation of the print defect sorting unit in the tablet printing apparatus 1G. [Diagram 34] FIG. 1 is a front view showing the configuration of a conventional tablet printing device 1X. [Diagram 35] 1A is a schematic cross-sectional view illustrating a tablet delivery operation from an upstream conveying means to a downstream conveying means in the tablet printing apparatus 1X. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] <<Overview of the embodiment of the present invention>> A tablet printing device according to an embodiment of the present disclosure is a tablet printing device that prints information on the front and back surfaces of tablets transported along a transport path, an upstream conveying means for conveying the tablet in a first direction while holding the tablet with one of its front and back surfaces facing downward facing the conveying surface; an upstream printing unit that prints information on the other of the front and back surfaces of the tablet being transported by the upstream transport means, the other surface facing upward; a downstream conveying means having a reversing means located above the upstream conveying means, which holds the tablet conveyed by the upstream conveying means with the other surface facing a conveying surface and reverses the tablet from the first direction to a second direction opposite to the first direction, and a downstream linear conveying means which then conveys the tablet in the second direction; a downstream printing unit that prints information on the one side of the tablet being transported by the downstream transport means, the upstream conveying means and the reversing means are disposed in a boundary region on the conveying path, facing each other with their conveying surfaces spaced apart by a predetermined distance; the reversing means has a suction means having an intake port facing a conveying surface of the upstream conveying means in the boundary area, The suction means sucks the other surface of the tablet on the conveying surface of the upstream conveying means to adsorb and hold the tablet on the conveying surface of the downstream conveying means, thereby transferring the tablet from the upstream conveying means to the downstream conveying means, The predetermined distance is configured to be adjustable by changing the position of the downstream transport means and / or the upstream transport means.

[0011] This configuration provides a tablet printing device capable of suppressing the misalignment and tilt of tablets on the conveying path during the process of transferring the tablets from the upstream conveying section to the downstream conveying section. As a result, printing defects in the downstream printing section caused by the misalignment of the tablets can be suppressed. Alternatively, a problem caused by the tilt of the tablet being caught in the gap between the upstream conveying means and the reversing means can be suppressed.

[0012] Furthermore, when changing the thickness of the tablet to be printed, an operation can be performed to adjust the gap between the reversing means and the upstream conveying means so as to fit the new tablet.

[0013] In another aspect, in any of the aspects described above, the inverting means is a rotary suction conveying means having a plurality of the air intakes on a circumferential surface thereof and configured to be capable of suctioning from the air intakes within a predetermined rotation angle range, The rotary suction conveying means may be configured to start suction when the air intake port faces a predetermined direction in the boundary area as the rotary suction conveying means rotates, thereby suctioning the other side of the tablet being conveyed by the upstream linear conveying means, thereby adsorbing and holding the tablet above the circumferential surface, and adsorbing and holding the tablet while rotating through the predetermined rotation angle range and conveying it to the downstream linear conveying means.

[0014] With this simple configuration, a tablet printing device can be realized that is capable of suppressing positional deviation and tilt of tablets on the conveying path during the process of transferring the tablets from the upstream conveying section to the downstream conveying section.

[0015] In another aspect, in any of the aspects described above, the inverting means includes a first rotary suction conveying means having a plurality of the suction ports on a circumferential surface thereof, the first rotary suction conveying means being configured to be capable of suctioning when the suction ports are in a first rotation angle range; a second rotary suction conveying means disposed above the first rotary suction conveying means, having a plurality of upper air intakes formed on a peripheral surface thereof, and configured to be capable of suctioning when the upper air intakes are in a second rotation angle range; a conveyor belt that is stretched between the first rotary suction conveying means and the second rotary suction conveying means and has a plurality of openings; a swing arm that supports the first rotary suction and transport means so as to be rotatable and swingable about a rotation center of the second rotary suction and transport means; an attitude control mechanism that defines a start angle and an end angle of the first rotation angle range; the first rotary suction conveying means starts suction when the intake port faces a predetermined direction in the boundary region as the means rotates, and sucks the other surface of the tablet conveyed by the upstream linear conveying means through the opening of the belt installed on the circumferential surface, thereby suctioning and holding the tablet on the conveying belt while rotating within the first rotation angle range, and conveying the tablet; the conveyor belt conveys the tablet to the second rotary suction conveying means while the tablet is suction-held on the conveyor belt, the first rotary suction conveying means rotates to suck the other surface of the tablet through the opening of the conveying belt installed on the peripheral surface, thereby suctioning and holding the tablet on the conveying belt while rotating in the second rotation angle range, and conveying the tablet to the downstream linear conveying means; the swing arm swings the first rotary suction transport means to change the position of the downstream transport means relative to the upstream transport means, The posture control mechanism may be configured to suppress changes in a start angle and an end angle of the first rotation angle range caused by the swinging of the first rotary suction and transport means.

[0016] With this configuration, the gap between the inverting means and the upstream conveying means can be freely adjusted to suit the thickness of the target tablet. In addition, in adjusting the gap, the rotation angle range in which the first rotary suction conveying means can suck through the intake port is maintained, and thus, when printing on tablets of different thicknesses, positional deviation or tilt of the tablet on the conveying path can be suppressed in the process of transferring the tablet from the upstream conveying means to the downstream conveying means.

[0017] In another aspect, in any of the aspects described above, the attitude control mechanism may be configured to be able to change the start angle and end angle of the first rotation angle range by a rotational driving means, and by changing the start angle and end angle, the predetermined direction in which the air intake port faces when the air intake port begins suction in the first rotary suction and transport means may be changed.

[0018] With this configuration, the attitude control mechanism can be operated to change the rotation angle range in which the rotating drum can draw air through the intake port, and the device can be set to the optimal angle range to suit the characteristics of the tablet, such as its shape and weight.

[0019] Further, the tablet printing method according to the embodiment is a tablet printing method for printing information on the front and back surfaces of a tablet transported along a transport path, The tablet is held in a state where one of the front and back surfaces of the tablet that faces downward faces a conveying surface, and conveyed upstream in a first direction; Printing information on the other of the front and back surfaces of the tablet being transported upstream, the other surface facing upward; The tablet conveyed upstream is held with the other surface facing the conveying surface, and the tablet is conveyed in such a way that it is inverted from the first direction to a second direction opposite to the first direction, and then conveyed downstream in the second direction. A tablet printing method for printing information on one side of the tablet being transported downstream, the upstream conveyance and the reverse conveyance face each other in a boundary region on the conveyance path with their conveyance surfaces spaced apart by a predetermined distance; In the reverse conveyance, a suction operation is performed from an intake port facing a conveying surface of the upstream conveying means in the boundary area, In the suction operation, the other surface of the tablet on the conveying surface of the upstream conveying means is sucked to adsorb and hold the tablet on the conveying surface of the downstream conveying means, thereby transferring the tablet from the upstream conveying means to the downstream conveying means, The predetermined distance may be adjusted by changing the positions of the downstream transport means and / or the upstream transport means.

[0020] With this configuration, it is possible to provide a tablet printing method that can suppress positional deviation and tilt of tablets on the conveying path during the process of transferring the tablets from the upstream conveying section to the downstream conveying section.

[0021] In another aspect, in any of the aspects described above, a tablet printing device capable of printing information on the front and back of tablets transported along a transport path includes a tablet supply unit that supplies tablets, an upstream transport means that transports the supplied tablets, an upstream printing unit that prints information on tablets transported by the upstream transport means, a downstream transport means arranged downstream of the upstream transport means, a downstream printing unit that prints information on tablets transported by the downstream transport means, a good product extraction unit arranged downstream of the downstream printing unit, a tablet return unit that returns the transported tablets to the tablet supply unit, a print defect sorting unit that removes print defects from the system, and a control means that controls these elements, and the tablets supplied from the tablet supply unit may be configured to be transported in a circular manner along a path that passes through the upstream transport means, the downstream transport means, and the tablet return unit and returns to the tablet supply unit.

[0022] With this configuration, it is possible to automate the operation of adjusting the tablet pitch on the transport path to an optimal value by increasing or decreasing the total number of tablets on the path through the function of circulating the tablets and the function of controlling the maximum number of tablets supplied and returned. As a result, it is possible to automate the adjustment of the setting conditions of the tablet printing device in response to changes in tablet type, etc., and it is possible to greatly improve the efficiency of the work of changing the setting conditions of the tablet printing device.

[0023] In another aspect, in any of the aspects described above, a tablet printing device that prints information on the front and back of a tablet transported along a transport path may be provided, in which the tablet supply section having a ball feeder further includes an abnormal tablet removal section that detects whether the tablet to be supplied is a fragment or whether the tablet has an abnormal shape, and when it is determined that the tablet to be supplied is a fragment or a tablet having an abnormal shape, the tablet is dropped from a ring-shaped flat area near the inside of the outer periphery of the ball feeder into the center of a mortar-shaped rotating member before being output to the supply lane, thereby preventing the abnormal tablet from being supplied to the upstream transport means.

[0024] This configuration avoids the inconvenience caused by providing an outlet or discharge passage in the ball feeder, while resolving the problem of tablet fragments or tablets with abnormal shapes becoming mixed in with the tablets being fed, causing blockages in the supply lane and resulting in frequent shutdowns of the tablet printing device.

[0025] In another aspect, in any of the aspects described above, a tablet printing device that prints information on the front and back of a tablet transported along a transport path may be provided, in which a tablet supply unit having a ball feeder is provided with an abnormal tablet removal unit, and when a score line is detected on the top surface of a tablet to be supplied, the abnormal tablet removal unit supplies the tablet to an upstream transport means as a score line detected tablet, and prints information on the front and back in the upstream printing unit and downstream printing unit, and when no score line is detected on the top surface of the tablet to be supplied, the tablet is dropped from a ring-shaped flat area near the inside of the outer periphery of the ball feeder into the center of a bowl-shaped rotating member.

[0026] Furthermore, tablets that have fallen into the center of the bowl-shaped rotating member and for which no score line was detected are pushed outward by the spiral blades of the bowl feeder and aligned in a single row along the outer periphery, and the abnormal tablet removal section measures again whether or not a score line is detected on the upper surface, and tablets for which a score line has been detected are supplied to the upstream conveying means.

[0027] With this configuration, when printing information on both sides of a tablet that has a score line on only one of the front and back sides, a tablet printing function can be realized that aligns the angle of the information printing on the front and back sides with the score line on one side, with a simple configuration that does not include a tablet delivery and transport mechanism for measuring the score lines on the front and back sides, a measurement camera, a sensor, etc. Also, by adopting a simple device configuration that does not include a mechanism for measuring the score lines on the front and back sides, it is possible to avoid the problems of reduced transport accuracy and transport failures that occur due to the complexity of the device configuration, and the problems of increased device costs.

[0028] In another aspect, in any of the aspects described above, the upstream printing unit and the downstream printing unit may be equipped with a linear motion mechanism that moves the print head forward or backward relative to a base, and a pair of passing detection sensors on both sides of the movement path of the print head on the base when it moves backward or forward, for detecting the passing height of the nozzle surface of the print head, and the passing detection sensors are configured so that the nozzle surface crosses some of the multiple optical paths when the print head moves backward or forward, and the passing height of the nozzle surface can be measured by detecting which optical path is blocked.

[0029] With this configuration, it is possible to detect ink adhering to the nozzle surface of the print head and prompt the removal of the ink, thereby reducing ink adhesion to areas other than the top and bottom surfaces of the tablet that can be detected by the inspection image capture unit, and suppressing the occurrence of defectively printed tablets in which ink adheres to areas other than the top and bottom surfaces of the tablet, making it difficult for the defective print sorting unit to remove them.

[0030] In another aspect, in any of the aspects described above, a print defect sorting unit is provided downstream of the downstream printing unit on the conveying path, which blows air at defective tablets whose front and / or back printing quality does not meet a predetermined printing standard, and discharges them from the system through the downstream conveying means, and the print defect sorting unit acquires a moving image in a plan view of the flying of the tablets with print defects, calculates a trajectory related to the discharge of the target tablets, and can identify discharge defects, and if the discharge operation of the target tablets is defective, records a tablet flight image, and if the discharge operation is not defective, records flight parameters based on the trajectory related to the discharge.

[0031] This configuration can improve the reliability of the print defect ejection operation. Furthermore, even if the ejection operation does not fail, early detection of equipment abnormalities in the print defect sorting unit is possible by monitoring the change over time in the flight parameters of the ejected tablets.

[0032] In addition, the circulating transport function can be used to automate the adjustment operation of the print defect sorting section when changing the type of tablet, etc., greatly improving the efficiency of the work of changing the settings of the tablet printing device.

[0033] First Embodiment The configuration of the tablet printing apparatus 1A according to the embodiment 1 will be described with reference to the drawings. Here, in this specification, the X direction, Y direction, and Z direction in each drawing may be the width direction, depth direction, and height direction, respectively, and the positive direction of the height direction may be the "up" direction, and the negative direction of the height direction may be the "down" direction.

[0034] In addition, the scale of the components in each drawing is not necessarily the same as the actual one. In addition, in order to make it easier to understand, illustrations of covers, etc. may be omitted. For example, some components, transport paths, etc. may be illustrated typically or roughly. In addition, in this specification, the symbol "~" used to indicate a numerical range includes the numerical values ​​at both ends. In addition, the materials, numerical values, etc. described in this embodiment are merely examples of preferred ones, and are not limited thereto. In addition, appropriate changes are possible within the scope of the technical idea of ​​this disclosure. In addition, combinations of parts of the configurations of other embodiments are possible within the scope of no contradiction.

[0035] <Configuration of the tablet printing device 1A> The configuration of the tablet printing apparatus 1A will be described with reference to the drawings. Fig. 1 is a front view showing an outline of the configuration of the tablet printing apparatus 1A (hereinafter, may be referred to as "apparatus 1A") according to embodiment 1, and Fig. 2 is a perspective view showing a schematic configuration of the apparatus 1A.

[0036] (Overall composition) The device 1A is a printing device that prints identification information such as characters, figures, and images representing a company name or product name on the front and back surfaces of tablets that constitute the outer surface of the tablets in the manufacturing process of medicines, foods, confectioneries, etc. As shown in Figs. 1 and 2, the device 1A includes a base 1 that supports each part and functions as a housing, a tablet supplying unit 2 that supplies tablets T, an upstream conveying means 3 that conveys the supplied tablets, an upstream printing unit 4U that prints information on tablets T conveyed by the upstream conveying means 3, a downstream conveying means 5 arranged after the upstream conveying means 3, a downstream printing unit 4D that prints information on tablets T conveyed by the downstream conveying means 5, a non-defective product extraction unit 8 and a discharge conveying means 9 arranged after the downstream printing unit 4D, and a control means 10.

[0037] (Outline of each part) The configuration of each part of the device 1A will be outlined below.

[0038] [Tablet T] Tablet T is a workpiece (printing target) that is the printing target of device 1A. Tablet T is made of various medicines, foods, snacks, etc., which are molded into a flat shape. Identification information for medical professionals and patients to identify the medicine, such as letters, figures, code images indicating the company name, product name, content, dosage form, etc., is printed on the front and / or back of tablet T, which are among the surfaces that make up the outer surface. Usually, different information is printed on the front and back of a tablet.

[0039] The tablet shape may be the same on the front and back surfaces, or may be different, such as having a specific shape such as a dividing line formed on one surface. The thickness of the tablet T may be, for example, 2 mm to 8 mm, but is not limited thereto. The shape of the tablet T in plan view may be a circle, an ellipse, an oval, a rectangle, a polygon, or other shapes such as a star or an irregular shape. The tablet T may be composed of a plurality of different shapes as long as the thickness is almost constant.

[0040] In this specification, the "front surface" or "back surface" of the tablet T supplied to the device 1A may refer to one surface seen by a viewer when the flat tablet T is arbitrarily placed and viewed in a plane, and the other surface located behind the front surface may refer to the "front surface." Alternatively, when the top and bottom surfaces of the tablet T have different shapes, either surface may be specified as the "front surface" or the "back surface."

[0041] [Tablet supply unit 2] The tablet supply section 2 is a unit that supplies multiple tablets T to the system, and is arranged on the base 1. It includes a hopper 21 that receives a large number of tablets T from above and sends them downward, and a feeder 22 that converts the multiple tablets T supplied from the hopper 21 into multiple rows and outputs them sequentially to the upstream conveying means 3.

[0042] In this example, as shown in Fig. 2, the feeder 22 is made of a disk-shaped member. The feeder 22 rotates around a central axis 22o (arrow R22 in Fig. 2), thereby causing a plurality of tablets T placed on the upper surface of the feeder 22 to move along the outer periphery by centrifugal force, and then outputs the tablets T sequentially to the upstream conveying means 3 through each of two supply holes 22a opened on the outer periphery. In this example, the tablets T are sorted into two rows and supplied in series to the upstream conveying means 3.

[0043] [Upstream conveying means 3] The upstream conveying means 3 is a conveying mechanism that holds the tablet T supplied from the tablet supply unit 2 with one of the front and back surfaces of the tablet T facing downward facing the conveying surface, conveys the tablet T in a first direction D1 (upper right direction in the plane of FIG. 1), and transfers the tablet T to the downstream conveying means 5 in the subsequent stage. While the tablet T is being conveyed by the upstream conveying means 3, the other surface of the tablet T facing upward is printed by the upstream printing unit 4U described later.

[0044] In this embodiment, the upstream conveying means 3 is composed of upstream linear conveying means 3L arranged on a base 1 in a straight line in a first direction D1, and is driven by a control means 10 to convey tablets T at a predetermined interval from the left to the right of the paper in Figure 1 (arrow T1 in Figures 1 and 2).

[0045] The upstream transport means 3 includes pulleys 31 and 32 constituting a pair of a drive pulley and a driven pulley, and a transport belt 33 suspended between them.

[0046] The conveyor belt 33 is a belt that holds and conveys tablets T on its upper surface, and holds tablets T on its upper surface mainly by gravity and the frictional force of the upper surface. The conveyor belt 33 conveys tablets T by the pulleys 31 being driven and controlled by an apparatus drive control unit (not shown). In this example, two conveyor belts 33 are suspended in the axial direction, and can hold and convey tablets T on the back surface of each of them.

[0047] Here, in order to reliably hold the tablets T on the conveyor belt 33, for example, the conveyor belt 33 may be provided with a plurality of air intakes (not shown) and a suction device (not shown) that sucks air from the air intakes, so that the tablets T placed on the conveyor belt 33 are reliably held and conveyed by being sucked and adsorbed. At this time, the suction force applied to the tablets T by the upstream conveying means 3 is auxiliary, and is far smaller than the suction force applied to hold the tablets T on the circumferential surface of the rotating drum 52 against gravity and centrifugal force.

[0048] The conveyor belt 33 may be a belt having the same specifications as a conveyor belt 53 in the downstream conveying means 5 described later, except for the circumferential length.

[0049] In addition, a detection means 34 is provided for detecting the time when the tablet T passes a predetermined position on the conveying path. The detection means 34 may be a reflective or transmissive optical sensor, a laser detector, an imaging element, a line camera capable of acquiring images of a plurality of linear pixels, or the like. The detection means 34 detects the time when the tablet T passes and outputs the detection result to the control means 10.

[0050] In addition, the device 1A shown in this example is configured so that the first direction is horizontal and printing is performed with the other side of the tablet T facing upward, but the first direction may also be inclined relative to the horizontal direction to an extent that allows the tablet to be transported.

[0051] [Upstream printing unit 4U] The upstream printing unit 4U is a printing unit arranged at a predetermined position on the conveying path in the upstream conveying means 3. The upstream printing unit 4U is arranged above the conveying belt 33 between pulleys 31 and 32, and performs printing on the other of the front and back surfaces of the tablet T conveyed by the upstream conveying means 3 that faces upward.

[0052] The upstream printing unit 4U is disposed on the base 1 and includes, from the upstream side to the downstream side of the transport path, a target image capturing unit 41U, a print head 42U, and an inspection image capturing unit 43U, in that order.

[0053] The target image capturing unit 41U is an image capturing means for capturing an image of the printing object with the tablet T being conveyed as the image capturing target, and is disposed opposite the conveying surface with a predetermined gap therebetween. The target image capturing unit 41U can be a line camera capable of capturing an image of a plurality of pixels arranged in a line in a direction perpendicular to the conveying direction. The captured image of the printing object is output to the control means 10, and the position and passing timing of the tablet T to be printed in the direction perpendicular to the conveying direction are detected by the control means 10 based on the image. It is possible to measure the angle of the score line of the tablet from the image of the printing object captured by the target image capturing unit 41U, and tablet printing by the print head 42U based on the score line angle information is possible.

[0054] The print head 42U is a print head that performs non-contact printing on the upper surface of the tablet T being conveyed, and is disposed opposite the conveying surface with a predetermined gap therebetween. For the print head 42U, an inkjet type print head having a plurality of nozzles in a line in a direction perpendicular to the conveying direction can be used. According to this print head 42U, based on the print data output from the control means 10 based on the image of the printing object, ink is selectively discharged from the nozzles corresponding to the passing position of the tablet T in the Y direction in accordance with the passing time of the tablet T, and a predetermined pattern is printed on the upper surface of the tablet T. Non-contact printing is suitable for printing on various medicines and foods from a hygienic point of view.

[0055] The inspection image capturing unit 43U is an image capturing means for capturing an image of the printed tablet T as an image capturing target, and is disposed opposite the conveying surface via a predetermined gap. The target image capturing unit 41U may be a line camera similar to the target image capturing unit 41U, or a two-dimensional image capturing element having a matrix-like element arrangement. The captured image of the printed object is output to the control means 10, and the control means 10 judges whether the print quality is good or bad based on the image.

[0056] [Downstream conveying means 5] The downstream conveying means 5 is located above the upstream conveying means 3, and is a conveying mechanism that holds the tablet T conveyed by the upstream conveying means 3 with the lower surface of the tablet T facing the conveying surface, flips the tablet T from a first direction D1 (toward the right on the paper in Figure 1) to a second direction D2 (toward the left on the paper in Figure 1), and then conveys the tablet T in the second direction D2.

[0057] In the device 1A, the downstream conveying means 5 is composed of an inverting means 5T that inverts the conveying direction of the tablets T from a first direction D1 to a second direction D2 (arrow T2 in Figs. 1 and 2), and a downstream linear conveying means 5L that is located downstream of the inverting means 5T in the conveying path and linearly conveys the inverted tablets T in the second direction D2 (arrow T3 in Figs. 1 and 2). While the tablets T are being conveyed by this downstream linear conveying means 5L, printing is performed on one of the upwardly facing surfaces of the tablets T by a downstream printing unit 4D described later.

[0058] The specific configuration is as follows: The downstream conveying means 5 is provided with a pair of driving pulleys 51 arranged on the base 1 via a movable frame 50, a rotating drum 52 (hereinafter, sometimes referred to as "rotary suction conveying means") that rotates with the driving pulleys 51 (arrow R52 in Figs. 1 and 2), a pressure pulley 54, and a conveying belt 53 suspended between them, and these elements form the reversing means 5T and the downstream linear conveying means 5L.

[0059] The conveyor belt 53 is a belt that holds and conveys the tablets T on its upper surface, and conveys the tablets T by driving and rotating the pulleys 51 (arrow R51 in Figs. 1 and 2) by the control means 10. In this embodiment, as an example, two conveyor belts 53 are suspended in the axial direction, and each of them can hold and convey a tablet T on its back surface.

[0060] 3(a) is a plan view of the conveyor belt 53, (b) is a side view, and (c) is a cross-sectional view of the conveyor belt 53 taken along line AA in (a). As shown in the figure, the conveyor belt 53 is, for example, an endless belt reinforced with a core wire, and is composed of, for example, a circumferential back rubber part 531 and a tooth rubber part 532 bonded to the back rubber part 531.

[0061] As shown in Fig. 3(a)(c), the back rubber part 531 of the conveyor belt 53 is removed within a range of width w in the center of the belt width direction perpendicular to the circumferential direction, and an opening 53a with an opening width w is opened in the gap between adjacent tooth rubber parts 532 in the circumferential direction. In the conveyor belt 53, the opening width w is smaller than the minimum dimension of the target tablet T in a plan view, and the tablet T can be placed on the back rubber part 531 on both sides of the opening 53a. At this time, the dividing line BL may face either up or down. Furthermore, by performing suction through the opening 53a in this state, the tablet T can be adsorbed and held on the back surface of the conveyor belt 53 suspended on the rotating drum 52 and conveyed.

[0062] Next, the configuration of the reversing means 5T will be described with reference to the drawings. 1, the rotating drum 52 constituting the reversing means 5T is provided with a suction mechanism in which a plurality of air intakes 52a are opened on the circumferential surface and communicate with a negative pressure chamber 52b formed inside the rotating drum 52 within a predetermined rotation angle range, enabling suction through the air intakes 52a. In the example shown in FIG. 1, the rotating drum 52 is configured such that the air intakes 52a communicate with the negative pressure chambers 52b within a rotation angle range from 6 o'clock to 0 o'clock in the counterclockwise direction based on the rotation center 52o.

[0063] The detailed structure of the reversing means 5T will be described below. 4(a) is a front cross-sectional view of the main part related to conveyance, in which the reversing means 5T is cut at the rotating drum 52 portion along the XZ plane, and (b) is a cross-sectional view of the reversing means 5T cut along the A2-A2 line in (a). As shown in Figs. 4(a) and (b), the reversing means 5T is attached to the base 1 via a movable frame 50, and the rotating drum 52 is rotatably attached to a hollow shaft 55, the axis of which constitutes the rotation center 52o of the reversing means 5T.

[0064] Rotating drum 52 has a hollow cylindrical structure in which both ends of a cylindrical portion 522 are sealed by a pair of flange portions 521, 523 and has a negative pressure chamber 52b inside. Flange portions 521, 523 are each rotatably attached to a hollow shaft 55 via a bearing 524. A seal member 525 for ensuring airtightness of negative pressure chamber 52b is interposed between the inner periphery of flange portion 523 and the outer periphery of hollow shaft 55. A conveyor belt 53 is suspended on the circumferential surface of rotating drum 52, and is configured such that when pulley 51 is driven to rotate, rotating drum 52 rotates with it (arrow R52 in FIGS. 1 and 2).

[0065] The cylindrical portion 522 that forms the peripheral surface of the rotating drum 52 has multiple air intakes 52a opened in the circumferential direction in the portion located below the conveyor belt 53, and the negative pressure chamber 52b of the rotating drum 52 is configured to communicate with the space above the conveyor belt 53 through the air intakes 52a and the openings 53a of the conveyor belt 53.

[0066] The hollow shaft 55 is fixed to the movable frame 50 (FX in Fig. 4(b)). The movable frame 50 is mounted to the base 1 so as to move parallel to the vertical direction (M50 in Figs. 1, 2 and 4(b)) by a linear motion mechanism (not shown), and the hollow shaft 55 is configured to move up and down. With this configuration, the position of the downstream conveying means 5 relative to the upstream conveying means 3 can be changed, and the distance (gap) between the inversion means 5T and the upstream conveying means 3 can be freely adjusted to suit the thickness of the target tablet T.

[0067] The hollow shaft 55 has as its main component a cylindrical hollow shaft 551 with a closed tip and a negative pressure chamber 55b inside, a dimple knob 552 is attached to the tip to prevent the rotating drum 52 from falling out, and a vacuum pipe 553 is connected to the open end of the base, which communicates with a vacuum exhaust device VP (not shown).

[0068] A plurality of openings 55a are formed on the peripheral surface of the hollow shaft 551 at a portion inserted into the rotating drum 52, and a partition member 554 is provided over a predetermined rotation angle range based on the rotation center 52o. The partition member 554 is fixed to the peripheral surface of the hollow shaft 551 by a fastener 555. The partition member 554 is a member that blocks the opening 55a of the hollow shaft 551 and the intake port 52a of the rotating drum 52, and defines the outer edge of the negative pressure chamber 52b. Therefore, by adjusting the rotation angle range in which the partition member 554 is attached to the hollow shaft 551, the angle range in which the partition member 554 does not exist can function as the negative pressure chamber 52b, and suction from the intake port 52a of the rotating drum 52 becomes possible in that rotation angle range.

[0069] As a result, according to the inversion means 5T, suction is initiated when the air intake 52a faces a predetermined direction, such as vertically downward, as the tablet T rotates, thereby sucking in the upper surface of the tablet T transported by the upstream linear conveying means 3L and adsorbing and holding the tablet T on the circumferential surface of the rotating drum 52, and while the tablet T rotates within a predetermined rotation angle range, the tablet T is adsorbed and held thereon until the conveying belt 53 separates from the circumferential surface of the rotating drum 52, and the tablet T is then transferred to the downstream linear conveying means 5L.

[0070] In the downstream linear conveying means 5L, the tablets T are conveyed linearly by the conveying belt 53. Here too, in order to reliably hold the tablets T on the conveying belt 53, for example, the conveying belt 53 may be provided with a plurality of air intakes (not shown) and a suction device (not shown) that sucks air from the air intakes, so that the tablets T placed on the conveying belt 53 are reliably held and conveyed by being sucked and adsorbed.

[0071] In addition, the device 1A shown in this example is configured so that the second direction D2 is horizontal and printing is performed with the other side of the tablet T facing upward, but the second direction D2 may also be configured to be inclined relative to the horizontal direction to an extent that allows the tablet to be transported.

[0072] [Downstream printing section 4D] The downstream printing unit 4D is a printing unit arranged at a predetermined position on the conveying path of the downstream linear conveying means 5L. The downstream printing unit 4D is arranged above the conveying belt 53 between the pulley 51 and the rotating drum 52, and performs printing on one of the front and back surfaces of the tablet T conveyed by the downstream conveying means 5 that faces upward.

[0073] The downstream printing unit 4D is disposed on the base 1 via a movable frame 50, and is configured to include, in this order from the upstream side to the downstream side of the transport path, a target image capturing unit 41D, a print head 42D, and an inspection image capturing unit 43D. The configurations of the target image capturing unit 41D, print head 42D, and inspection image capturing unit 43D in the downstream printing unit 4D are the same as the configurations of the target image capturing unit 41U, print head 42U, and inspection image capturing unit 43U in the upstream printing unit 4U, respectively, and therefore will not be described.

[0074] [Good product extraction section 8] The non-defective product extraction unit 8 is disposed after the downstream printing unit 4D on the conveying path, and is a mechanism unit that transfers tablets T related to non-defective products with good print quality from the downstream conveying means 5 to the discharge conveying means 9. In this example, the non-defective product extraction unit 8 ejects air from the side toward the tablets T on the conveying path of the downstream linear conveying means 5L, thereby dropping the tablets T onto the conveying path of the discharge conveying means 9 below and transferring them thereto (arrow T4 in Figs. 1 and 2).

[0075] [Discharge conveying means 9] The discharge conveying means 9 is a conveying mechanism that conveys the non-defective tablets T supplied from the non-defective product extraction unit 8 and discharges them outside the system (arrow T6 in Figs. 1 and 2). The upstream conveying means 3 includes a pair of drive and driven pulleys 91, 92, and a conveying belt 93 suspended between them.

[0076] The print quality of the front and back surfaces of the tablet T is judged by the control means 10 based on the printed object images captured by the inspection image capturing units 43U and 43D. When the print quality of the front and back surfaces of the target tablet T meets a predetermined printing standard, the non-defective product extraction unit 8 ejects air based on an instruction from the control means 10 to transfer the target tablet T from the downstream linear conveying means 5L to the discharge conveying means 9 (arrow T4 in Figs. 1 and 2).

[0077] Furthermore, if at least one of the printing quality on the front and back sides of the target tablet T does not meet the specified printing standard, based on the instructions of the control means 10, the non-defective product extraction unit 8 does not eject air, and the tablet T is not transferred to the discharge conveying means 9, but is instead passed directly through the downstream conveying means 5 and discharged outside the system (arrow T5 in Figures 1 and 2).

[0078] [Control means 10] The control means 10 is electrically connected to the tablet supply unit 2, the upstream conveying means 3, the upstream printing unit 4U, the downstream conveying means 5, the downstream printing unit 4D, the non-defective product extraction unit 8, and the discharge conveying means 9, and outputs control signals to control the operation of each unit. The control means 10 comprises a control unit 11 that receives signals from each unit and issues control signals to them, and a drive unit 12 that applies current to drive means such as motors and piezoelectric elements in each unit based on the control signals to operate them.

[0079] The control unit 11 is realized, for example, as a computer having a general CPU (Central Processing Unit), RAM (Random Access Memory), and programs executed by these. The control unit 11 reads out a control program related to the device 1A from a storage device or the like into the RAM and executes it, thereby controlling each unit constituting the device 1A to operate in a linked manner, thereby realizing the functions of the device 1A.

[0080] The drive unit 12 is composed of various motors that operate the feeder 22, the upstream conveying means 3, the downstream conveying means 5 and the discharge conveying means 9, as well as drive circuits for driving the print heads of the upstream printing unit 4U and the downstream printing unit 4D, the upstream conveying means 3, the downstream conveying means 5 and the electromagnetic air valves in the non-defective product extraction unit 8.

[0081] <Operation of Device 1A> The operation of the device 1A having the above configuration will now be described. First, in the device 1A, the upstream conveying means 3 holds the tablet T with one of its front and back surfaces facing downward facing opposite the conveying surface of the conveyor belt 33, and conveys it in a first direction D1 (arrow T1 in Figures 1 and 2).

[0082] At this time, the upstream printing unit 4U prints information on the other of the front and back surfaces of the tablet T being transported by the upstream transport means 3, which faces upward.

[0083] Next, in the device 1A, the downstream conveying means 5 holds the tablet T transported by the upstream conveying means 3 with the other surface facing the conveying surface of the conveying belt 53, and flips the tablet T from the first direction D1 to a second direction D2 opposite to the first direction (same, arrow T2), and then transports the tablet T in a straight line in the second direction D2 (same, arrow T3).

[0084] At this time, the downstream printing unit 4D prints information on the one side of the tablet T being transported by the downstream transport means 5 in the second direction D2.

[0085] In addition, when changing the thickness of the tablet T to be printed, the movable frame 50 is moved parallel to the base 1 in the vertical direction (M50) by a linear motion mechanism not shown in the figure, thereby adjusting the height of the rotating drum 52 supported on the hollow shaft 55, and adjusting the distance (gap) between the inversion means 5T and the downstream conveying means 5 to fit the new tablet T.

[0086] Through the above operations, the device 1A can realize a tablet printing operation for printing information on the front and back surfaces of tablets transported along the transport path.

[0087] <Effects> As described above, the device 1A is equipped with an inversion means 5T that is located above the upstream conveying means 3, holds the tablet T conveyed by the upstream conveying means 3 with its lower surface facing the conveying surface, and inverts the tablet T from the first direction D1 to the opposite second direction D2, and the inversion means 5T has a rotating drum 52 with multiple air intakes 52a opened on its circumferential surface and configured to allow suction from the air intakes 52a within a predetermined rotation angle range, and the rotating drum 52 begins to suction when the air intakes face a predetermined direction in the boundary area as it rotates, thereby suctioning the upwardly facing surface of the tablet T conveyed by the upstream conveying means 3 to adsorb and hold the tablet T above the circumferential surface, and adsorbs and holds the tablet T while rotating within the predetermined rotation angle range to convey it to the downstream linear conveying means 5L.

[0088] As described above, in the conventional tablet printing device 1X, when tablets are transferred from the upstream conveying section to the downstream conveying section, the suction of the tablet T is released to cause the tablet T to fall from the circumferential surface of the upper rotary suction conveying means onto the lower downstream conveying section. As a result, there was an issue that the tablet T was pulled back by the negative pressure from the upstream side in the conveying direction as it fell, which was a cause of the tablet being misaligned or tilted on the conveying path.

[0089] As a result, conventional tablet printing devices 1X were unable to apply the negative pressure necessary to reliably adsorb and hold tablets T on the peripheral surface against the centrifugal force of the rotating drum, making it difficult to stably transport tablets as speeds increased.

[0090] In contrast, according to the device 1A, in the above series of operations, during the process of transferring the tablets T from the upstream conveying means 3 to the downstream conveying means 5, it is possible to suppress positional deviation and tilt of the tablets T on the conveying path, which occurred in the conventional tablet printing device 1X.

[0091] Fig. 5 is a schematic cross-sectional view explaining the tablet delivery operation from the upstream conveying means 3 to the downstream conveying means 5 in the device 1A. As shown in Fig. 5, the upstream conveying means 3 and the reversing means 5T are arranged facing each other with the conveying surfaces of the respective conveyor belts 33, 53 spaced apart by a predetermined distance δ at the boundary region BR on the conveying path. The predetermined distance δ constitutes the gap δ between the upstream conveying means 3 and the reversing means 5T, and may be, for example, 5 to 20% longer than the thickness of the tablet at the narrowest part.

[0092] In the device 1A, the downstream conveying means 5 has a rotating drum 52 with an air intake 52a that faces the conveying surface of the conveying belt 33 of the upstream conveying means 3 in the boundary region BR, and this rotating drum 52 sucks in the upward facing surface of the tablet T on the conveying surface of the conveying belt 33 of the upstream conveying means 3 to adsorb and hold the tablet T on the conveying surface of the conveying belt 53 of the downstream conveying means 5, thereby transferring the tablet T.

[0093] At this time, in the process of starting suction of the tablets T in the boundary region BR and transferring them from the conveyor belt 33 of the upper upstream conveying means 3 to the conveyor belt 53 on the circumferential surface of the rotating drum 52 below, no force other than gravity is exerted in a direction that hinders the transfer of the tablets T. Therefore, by applying a suction pressure P sufficient against gravity from the intake port 52a, positional deviation and inclination of the tablets T on the conveying path are suppressed in the transfer process.

[0094] As a result, printing defects in the downstream printing unit 4D caused by misalignment of the tablet can be suppressed, and a problem caused by the tilt of the tablet being caught in the gap δ between the upstream conveying means 3 and the rotating drum 52 and being damaged can be suppressed.

[0095] Furthermore, according to the device 1A, even if the centrifugal force of the rotating drum increases as the speed increases, the tablet T can be securely adsorbed and held on the peripheral surface by applying sufficient negative pressure to counter the centrifugal force, thereby enabling stable high-speed transportation.

[0096] Furthermore, when changing the thickness of the tablet T to be printed, the movable frame 50 can be moved parallel to the vertical direction to adjust the gap δ between the inversion means 5T and the upstream conveying means 3 to fit the new tablet T.

[0097] Second Embodiment The tablet printing apparatus 1B according to the second embodiment will be described in detail below with reference to the drawings.

[0098] <Configuration of the tablet printing device 1B> 6 is a front view showing an outline of the configuration of a tablet printing apparatus 1B (hereinafter, sometimes referred to as "apparatus 1B") according to embodiment 2. The apparatus 1B according to embodiment 2 differs from the apparatus 1A according to embodiment 1 in the configuration of the reversing means 5TB in the downstream conveying means 5B, and other configurations are the same as those of the apparatus 1A shown in FIG. 1. Therefore, hereinafter, the configuration of the reversing means 5TB in the downstream conveying means 5B of the apparatus 1B will be mainly outlined, and the other configurations will be assigned the same numbers as those of the apparatus 1A and will not be described.

[0099] [Configuration of downstream conveying means 5B] The following will explain the outline of the configuration of the downstream transport means 5B in the apparatus 1B.

[0100] The downstream conveying means 5B is the same as the device 1A in that it is composed of an inverting means 5TB located above the upstream conveying means 3 and inverting the conveying direction of the tablets T from a first direction D1 (rightward in the paper of FIG. 6, arrow T1) to a second direction D2 (leftward in the paper of FIG. 6) (arrow T2 in FIG. 6), and a downstream linear conveying means 5LB located downstream of the inverting means 5TB in the conveying path and linearly conveying the inverted tablets T in the second direction D2 (arrow T3 in the same). When the tablets T are being conveyed (arrow T3 in the same) by the downstream linear conveying means 5L, printing is performed on the upper surface of the tablets T from the downstream printing unit 4D.

[0101] In the device 1B, as shown in FIG. 6, the inversion means 5TB is composed of a swing arm 6 supported on the base 1, a rotating drum 52 supported on the swing arm 6, a rotating drum 57 arranged at the rotation center 57o of the swing arm 6, an intermediate suction means 58 arranged in the space between the rotating drum 52 and the rotating drum 57, and a conveying belt 53.

[0102] The specific configuration is as follows. The downstream conveying means 5B includes a driving pulley 51 disposed on the base 1, a rotating drum 57 which rotates with the driving pulley 51 (arrow R57 in the same figure), a rotating drum 52 disposed on the base 1 via a swinging arm 6, a pressure pulley 54, and a conveying belt 53 suspended between them, and these elements constitute the reversing means 5TB and the downstream linear conveying means 5LB. Of these, the configurations of the pulley 51 and the pressure pulley 54 are the same as those of the device 1A, except that they are supported on the base 1. The configuration of the conveying belt 53 is the same as that of the device 1A shown in Figures 3(a), (b), and (c), except for the circumferential length.

[0103] The swing arm 6 is mounted on the base 1 so as to swing (arrow R6) around the rotation center 57o of the rotating drum 57 by a swing mechanism described later, and is configured so that the swinging moves the rotating drum 52 up and down. With this configuration, the height of the rotating drum 52 relative to the upstream conveying means 3 can be changed, and the gap δ between the reversing means 5TB and the upstream conveying means 3 can be freely adjusted to suit the thickness of the target tablets T.

[0104] In the example shown in FIG. 6, similarly to device 1A, rotating drum 52 is configured such that air intake 52a communicates with negative pressure chamber 52b within a rotation angle range from 6 o'clock to midnight in a counterclockwise direction based on center of rotation 52o (hereinafter sometimes referred to as the "first rotation angle range").

[0105] As shown in Fig. 6, rotating drum 57 also has a suction mechanism in which a plurality of air intakes 57a are opened on the circumferential surface and communicate with negative pressure chambers 57b formed inside rotating drum 57 within a predetermined rotation angle range, enabling suction through air intakes 57a. In the example shown in Fig. 6, rotating drum 57 is configured such that air intakes 57a communicate with negative pressure chambers 57b in a rotation angle range from about 2 o'clock to about 0 o'clock (slightly toward 11 o'clock) in the counterclockwise direction with respect to rotation center 57o (hereinafter, sometimes referred to as a "second rotation angle range").

[0106] In addition, the intermediate suction means 58 also has a plurality of air intake ports 58a that communicate with the negative pressure chamber 58b inside the intermediate suction means 58 on the wall surface (on the right side of the paper in Figure 6) on the side of the conveyor belt 53 that conveys the tablets T, making it possible to suction through the openings 53a of the conveyor belt 53.

[0107] The detailed structure of the reversing means 5TB will be described below. Fig. 7(a) is a front cross-sectional view of the main part of the reversing means 5TB related to conveyance, obtained by cutting the rotating drums 52 and 57 of the reversing means 5TB along the XZ plane, and Fig. 7(b) is a cross-sectional view of the reversing means 5TB cut along the line A3-A3 in Fig. 7(a). Fig. 8 is a view of the reversing means 5T as seen from the arrow B1 in Fig. 7(a).

[0108] 7(a) and 7(b), in the reversing means 5TB, a hollow shaft 59 is fixed to the base 1. The swing arm 6 has a base portion supported by the hollow shaft 59 and swings around the hollow shaft 59. In addition, a rotating drum 57 is attached to the hollow shaft 59 so as to be freely rotatable.

[0109] A hollow shaft 55 is rotatably supported at the tip of the swing arm 6, and the rotating drum 52 is rotatably attached to the hollow shaft 55. As a result, the rotating drum 52 rotates around the hollow shaft 55 and swings around the hollow shaft 59 based on the movement of the swing arm 6.

[0110] Rotating drum 57 has a hollow cylindrical structure in which both ends of a cylindrical portion 572 are sealed by a pair of flange portions 571, 573 and has a negative pressure chamber 57b inside. Flange portions 571, 573 are each rotatably attached to a hollow shaft 59 via a bearing 574. A seal member 575 for ensuring airtightness of negative pressure chamber 57b is interposed between the inner periphery of flange portion 573 and the outer periphery of hollow shaft 59. A conveyor belt 53 is suspended on the circumferential surface of rotating drum 57, and is configured such that when pulley 51 (see FIG. 6) is driven to rotate, rotating drum 57 rotates with it (arrow R57 in the same figure).

[0111] The cylindrical portion 572 that forms the peripheral surface of the rotating drum 57 has multiple air intakes 57a opened circumferentially in the portion located below the conveyor belt 53, and the negative pressure chamber 57b of the rotating drum 57 is configured to communicate with the external space through the openings 53a in the conveyor belt 53.

[0112] The hollow shaft 59 is fixed to the base 1 by a flange 590. A pulley 72 around which a toothed belt 73 is suspended is attached (fixed) to the hollow shaft 59. The hollow shaft 59 has as its main component a cylindrical hollow shaft 591 with a closed end and a negative pressure chamber 59b inside, a dimple knob 592 is attached to the end of the hollow shaft 59 to prevent the rotating drum 57 from falling out, and a vacuum pipe 593 communicating with a vacuum exhaust device VP (not shown) is connected to the open end of the base.

[0113] A plurality of openings 59a are formed on the circumferential surface of the hollow shaft 591, at a portion inserted into the rotating drum 57, and a partition member 594 is provided over a predetermined rotation angle range based on the rotation center 57o. The partition member 594 is fixed to the circumferential surface of the hollow shaft 591 by a fastener 595. This partition member 594 is a member that blocks the opening 59a of the hollow shaft 591 and the intake port 57a of the rotating drum 57, and defines the outer edge of the negative pressure chamber 57b. Therefore, by adjusting the rotation angle range in which the partition member 594 is attached to the hollow shaft 591, the angle range in which the partition member 594 does not exist can be made to function as the negative pressure chamber 57b, and suction through the intake port 57a of the rotating drum 57 can be achieved in that rotation angle range.

[0114] The swing arm 6 has a structure in which an arm member 61 is rotatably attached to a hollow shaft 59 at its base via a bearing 63, and rotatably holds a hollow shaft 55 at its tip via a bearing 62. The swing arm 6 is swung by a drive mechanism 16. That is, a flange 66 is connected to the arm member 61 of the swing arm 6 in the axial direction of the hollow shaft 59, and the flange 66 is further connected to an output shaft of a servo motor 64 via a reducer 65. The servo motor 64 is fixed to the base 1 together with the reducer 65 by a stay 67. This allows the arm member 61 to swing around the hollow shaft 59 by the rotation of the servo motor 64.

[0115] The rotating drum 52 has the same configuration as the device 1A shown in FIGS. 4(a) and 4(b), so the same components are designated by the same reference numerals and the description thereof will be omitted.

[0116] As described above, the hollow shaft 55 is rotatably held by the arm member 61 via the bearing 62. In addition, the hollow shaft 55 is fitted with a driven pulley 71 around which a toothed belt 73 is suspended.

[0117] Here, in the device 1B, the pulley 71, the drive pulley 72, and the toothed belt 73 constitute an attitude control mechanism 7 for the hollow shaft 55 of the rotating drum 52 and the partition member 554 installed inside the negative pressure chamber 52b. As a result, the attitude control mechanism 7 controls the attitude of the negative pressure chamber 52b on the circumferential surface (specifically, the angle about the center of rotation 52o).

[0118] In the posture control mechanism 7, as an example, the driven pulley 71 attached (fixed) to the hollow shaft 55 and the drive pulley 72 attached (fixed) to the hollow shaft 59 are set to have an equivalent number of teeth (in other words, the same diameter), and the hollow shaft 59 rotatably supported by the arm member 61 is connected in the forward direction at a reduction ratio equivalent to that of the hollow shaft 55. As a result, when the swing arm 6 swings, the pulley 72 is constrained from rotating by the hollow shaft 59 fixed to the base 1, so that the toothed belt 73 is conveyed, and thus the pulley 71 rotates, and the hollow shaft 55 rotates.

[0119] At this time, the hollow shaft 55 rotates so as to compensate for the angle change caused by the swing, so that the absolute angle of the hollow shaft 55 around the axis of the rotation center 52o in the XZ plane in FIG. 6 does not change, and the posture of the hollow shaft 55 is maintained. At the same time, the absolute angle of the partition member 554 is also maintained. That is, when viewed from a viewpoint outside the reversing means 5TB, the driven pulley 71 and the fixed pulley 72 maintain the same positions in their respective circumferential directions when the swing arm 6 swings. Therefore, the angle range in which the partition member 554 does not exist around the rotation center 52o is maintained, and the rotation angle range in which the rotating drum 52 can suck air through the intake port 52a is maintained.

[0120] The attitude control mechanism 7 is a mechanism that defines the start angle and end angle of the first rotation angle range, and in this embodiment, the attitude control mechanism 7 functions as an attitude maintaining mechanism.

[0121] Here, the starting angle of the first rotation angle range refers to the rotation angle at which suction begins from the air intake port 52a as the rotating drum 52 rotates, and the ending angle of the first rotation angle range refers to the rotation angle at which suction from the air intake port 52a is released as the rotating drum 52 rotates.

[0122] Except for the above two points, the hollow shaft 55 has the same configuration as the device 1A shown in FIGS. 4(a) and 4(b), and therefore the same components are designated by the same reference numerals and their explanations are omitted.

[0123] The intermediate suction means 58 is a suction mechanism disposed in the space between the rotating drum 57 and the rotating drum 52, and has a negative pressure chamber 58b therein, which is connected to a vacuum exhaust device VP (not shown). In addition, a plurality of air intakes 58a are provided on the wall surface in the upper right direction in FIG. 7(a).

[0124] According to the reversing means 5TB having the above configuration, when the intake port 52a faces a predetermined direction, such as vertically downward, as the reversing means 5TB rotates, suction is started to suck the upper surface of the tablet T conveyed by the upstream linear conveying means 3L, and the tablet T is adsorbed and held on the peripheral surface of the rotating drum 52, and while rotating through a predetermined rotation angle range, the tablet T is adsorbed and held and conveyed until the conveying belt 53 separates from the peripheral surface of the rotating drum 52. Thereafter, the tablet T is adsorbed and held on the conveying belt 53 by the intermediate suction means 58 and conveyed to the periphery of the rotating drum 57, and further adsorbed and held on the peripheral surface of the rotating drum 57, and while rotating through a predetermined rotation angle range, the tablet T is adsorbed and held and conveyed, and transferred to the downstream linear conveying means 5LB.

[0125] In the downstream linear conveying means 5LB, the tablets T are conveyed linearly by a conveying belt 53. As in the device 1A, the tablets T placed on the conveying belt 53 may be sucked and adsorbed.

[0126] Similarly to the device 1A, the first direction D1 and the second direction D2 may be configured to be inclined with respect to the horizontal direction to an extent that allows tablet transport.

[0127] <Device 1B Operation> According to the device 1B having the above configuration, like the device 1A, it is possible to realize a tablet printing operation for printing information on the front and back surfaces of tablets transported along the transport path.

[0128] In addition, when changing the thickness of the tablet T to be printed, the servo motor 64 is driven to swing the oscillating arm 6 around the hollow shaft 59, thereby adjusting the height of the rotating drum 52 supported on the hollow shaft 55, and adjusting the gap δ between the inversion means 5TB and the downstream conveying means 5 to suit the thickness of the tablet T.

[0129] At this time, in the device 1B, the rotatably supported hollow shaft 59 is connected in the forward direction at a reduction ratio equivalent to that of the hollow shaft 55, so that the hollow shaft 55 rotates so as to compensate for the angle change accompanying the swing of the swing arm 6, and the postures of the hollow shaft 55 and the partition member 554 are maintained. Therefore, the rotation angle range in which the rotating drum 52 can suck air through the intake port 52a is maintained.

[0130] <Effects> As described above, in the device 1B, the reversing means 5TB includes a rotating drum 52 having a plurality of air intakes 52a formed on the circumferential surface thereof and configured to be capable of suctioning when the air intakes 52a are in a first rotation angle range; a rotating drum 57 arranged above the rotating drum 52, with a plurality of upper air intakes 57a formed on a circumferential surface thereof, and configured to be capable of suction when the upper air intakes 57a are in a second rotation angle range; The apparatus includes a rotating drum 52 and a conveyor belt 53 that is stretched around the rotating drum 57 and has a plurality of openings 53a formed therein. The rotating drum 52 starts suction when the intake port 52a faces a predetermined direction in the boundary region BR as the rotating drum 52 rotates, and sucks the other side of the tablet T conveyed by the upstream linear conveying means 3L through an opening 53a in the belt installed on the circumferential surface, thereby adsorbing and holding the tablet T on the conveying belt 53 while rotating in the first rotation angle range, and conveying the tablet T. The conveyor belt 53 conveys the tablets T to the rotating drum 57 while the tablets T are adsorbed and held on the conveyor belt 53. The rotating drum 57 is characterized in that, by rotating, the other side of the tablet T is sucked in through an opening 53a of the conveyor belt 53 mounted on the circumferential surface, thereby adsorbing and holding the tablet on the conveyor belt while rotating through a second rotation angle range, and transporting it to the downstream linear conveying means 5TL. With this configuration, similarly to the device 1A, in the downstream conveying means 5B, the rotating drum 52 having the intake port 52a facing the conveying surface of the conveying belt 33 of the upstream conveying means 3 sucks the upward facing surface of the tablet T on the conveying surface of the conveying belt 33 of the upstream conveying means 3, and adsorbs and holds the tablet T on the conveying surface of the conveying belt 53 of the downstream conveying means 5, thereby transferring the tablet T. This prevents the tablet T from being displaced or tilted on the conveying path.

[0131] Furthermore, the device 1B includes a swing arm 6 that supports the rotating drum 52 so as to be rotatable and swingable about the center of rotation of the rotating drum 57; and an attitude control mechanism (7) that defines a start angle and an end angle of the first rotation angle range, The swing arm 6 swings the rotary drum 52 to change the position of the downstream conveying means 5B relative to the upstream conveying means 3, The posture control mechanism 7 is characterized by compensating for changes in the start angle and end angle of the first rotation angle range that accompany the swinging of the rotating drum 52.

[0132] With this configuration, the height of the rotating drum 52 relative to the upstream conveying means 3 can be changed, and the gap δ between the inversion means 5TB and the upstream conveying means 3 can be freely adjusted to suit the thickness of the target tablets T.

[0133] At this time, the rotation angle range within which the rotating drum 52 can draw air through the intake port 52a is maintained, thereby suppressing misalignment and tilt of the tablets T on the conveying path during the process of transferring the tablets T from the upstream conveying means 3 to the downstream conveying means 5B when printing on tablets T of different thicknesses.

[0134] Third Embodiment In the device 1B of embodiment 2, the rotating drum 52 of the inversion means 5TB is configured so that the air intake 52a opened on the peripheral surface is capable of suction when it is in a first rotation angle range, and the posture control mechanism 7 is configured so that the rotation angle range in which suction is possible is maintained by compensating for changes in the start angle and end angle of the first rotation angle range that accompany the oscillation of the rotating drum 52.

[0135] In contrast, the device 1C of embodiment 3 is characterized in that the start angle and end angle of the rotation angle range at which air can be sucked in from the intake port 52a of the rotating drum 52 can be adjusted by operating the attitude control mechanism 7.

[0136] <Configuration of tablet printing device 1C> The tablet printing apparatus 1C according to the third embodiment will be described in detail below with reference to the drawings. Fig. 9 is a front view showing an outline of the configuration of a tablet printing apparatus 1C (hereinafter, sometimes referred to as "apparatus 1C") according to embodiment 3. The apparatus 1C differs from the tablet printing apparatus 1B according to embodiment 2 in the configuration of the attitude control mechanism 7 in the downstream conveying means 5C, and the other configurations are the same as those of the apparatus 1B shown in Figs. 6, 7, and 8. Therefore, in the following, the configuration of the attitude control mechanism 7 in the downstream conveying means 5C in the apparatus 1C will be mainly outlined, and the other configurations will be assigned the same numbers as those in the apparatus 1B and will not be described.

[0137] [Configuration of downstream conveying means 5C] The following describes an outline of the configuration of downstream transport means 5C in apparatus 1C.

[0138] 9, in the apparatus 1C, the downstream conveying means 5C is composed of a reversing means 5TC and a downstream linear conveying means 5LB, and the reversing means 5TC is composed of a swing arm 6 supported on the base 1, a rotating drum 52 supported on the swing arm 6, a rotating drum 57 disposed at a rotation center 57o of the swing arm 6, and an intermediate suction means 58 and a conveying belt 53 disposed in the space between the rotating drum 52 and the rotating drum 57, which is the same as the apparatus 1B. In addition, the configurations of the downstream linear conveying means 5LB, the pulley 51, the conveying belt 53, and the pressure pulley 54 are also the same as those of the apparatus 1B.

[0139] In the device 1C, as shown in FIG. 9, the rotating drum 52 is configured so that the air intake 52a communicates with the negative pressure chamber 52b within a rotation angle range set in the counterclockwise direction based on the center of rotation 52o, and the start angle and end angle of this rotation angle range are configured to be changeable (52a (after adjustment) in FIG. 9).

[0140] The detailed structure of the reversing means 5TC will now be described. Fig. 10(a) is a front cross-sectional view of the main part of the reversing means 5TC related to conveyance, in which the reversing means 5TC is cut at the rotating drums 52 and 57 in the XZ plane, and (b) is a cross-sectional view of the reversing means 5TC cut at the line A4-A4 in (a). Fig. 11 is a view of the reversing means 5TC as seen from the arrow B2 in Fig. 10(a). Fig. 12 is a view of the reversing means 5TC as seen from the arrow B3 in Fig. 10(b).

[0141] 10(a) and 10(b), in the reversing means 5TC, similarly to the device 1B, a hollow shaft 59 is fixed to the base 1. The swing arm 6 has a base portion supported by the hollow shaft 59 and swings around the hollow shaft 59. In addition, a rotating drum 57 is attached to the hollow shaft 59 so as to be freely rotatable.

[0142] A hollow shaft 55 is rotatably supported at the tip of the swing arm 6, and the rotating drum 52 is rotatably attached to the hollow shaft 55. As a result, the rotating drum 52 rotates around the hollow shaft 55 and swings around the hollow shaft 59 based on the movement of the swing arm 6.

[0143] The configuration and function of rotating drum 57 are the same as those of device 1B, except that a bearing 576 is interposed between rotating drum 57 and base 1. That is, in device 1C, flange portion 573 is rotatably attached to base 1 (part 1a in FIGS. 10 and 11) via bearing 576 in terms of layout.

[0144] The configuration and function of the hollow shaft 59 are the same as those of the device 1B, except that it is fixed to the base 1 via a stay 67C of the swing arm 6.

[0145] The configuration and function of the swing arm 6 are the same as those of the device 1B, except for the structure of the drive mechanism 16C connected to the servo motor 64C. That is, in the device 1C, the swing arm 6 has a structure in which an arm member 61 is rotatably attached to a hollow shaft 59 via a bearing 63 at its base, and rotatably holds a hollow shaft 55 via a bearing 62 at its tip, similar to that of the device 1B.

[0146] In addition, in the device 1C, as the drive mechanism 16C, a servo motor 64C is fixed to the base 1 together with a reducer 65C by a stay 67C, and the arm member 61 is swung by a link mechanism 68 connected to the output shaft of the reducer 65C. This link mechanism 68 is composed of a rotating arm 681 connected to the output shaft of the reducer 65C, and a link 683 rotatably connected to the rotating arm 681 and the arm member 61 by joints 682 and 684 at both ends. This allows the arm member 61 to swung around the hollow shaft 59 by the rotation of the servo motor 64C.

[0147] The configuration and function of rotating drum 52 are the same as those of device 1B, except that the start and end angles of the rotation angle range in which suction from intake port 52a of rotating drum 52 can be achieved can be adjusted by attitude control mechanism 7.

[0148] The structure and function of the hollow shaft 55 are the same as those of the device 1B.

[0149] The configuration and function of the intermediate suction means 58 are the same as those of the device 1B.

[0150] The attitude control mechanism 7C for the rotating drum 52 in the apparatus 1C will be described. In the apparatus 1C, as the attitude control mechanism 7C, a driven pulley 71 is attached to the hollow shaft 55, and a toothed belt 73 is suspended therearound. A reducer 76 and a servomotor 75 are fixed to the base end of the arm member 61 of the swing arm 6 by a stay 77, and a drive pulley 74 is attached to the output shaft of the reducer 76, and the toothed belt 73 is suspended therearound.

[0151] With this configuration, when the servo motor 75 is driven to rotate, the hollow shaft 55 rotatably supported by the arm member 61 rotates, and the absolute angle of the hollow shaft 55 around the axis centered on the rotation center 52o in the XZ plane in FIG. 9 changes, and at the same time, the absolute angle of the partition member 554 also changes (see 554 (reference angle) and 554 (after adjustment) in FIG. 10(a)). As a result, the angle range in which the partition member 554 does not exist around the rotation center 52o changes, and the start angle and end angle of the rotation angle range in which the rotating drum 52 can suck through the intake port 52a are changed. As a result, the angle at which the intake port 52a starts sucking in the boundary region BR as the rotating drum 52 rotates can be set to an optimal angle according to the characteristics of the tablet T, such as the shape and weight.

[0152] <Operation of Device 1C> Like the device 1B, the device 1C having the above configuration can realize a tablet printing operation for printing information on the front and back surfaces of tablets transported along the transport path.

[0153] As with device 1B, the oscillating arm 6 is swung to adjust the gap δ between the inversion means 5TC and the downstream conveying means 5 to suit the thickness of the tablet T to be printed, and the posture control mechanism 7 compensates for the angle change associated with the swing, thereby maintaining the rotation angle range in which suction by the rotating drum 52 is possible.

[0154] Furthermore, by operating the posture control mechanism 7, the absolute angle of the hollow shaft 55 and the partition member 554 around the axis centered on the rotation center 52o is changed, thereby changing the rotation angle range in which the rotating drum 52 can suck air through the intake port 52a, and the device can be set to an optimal angle range suited to the characteristics of the tablet T, such as its shape and weight.

[0155] The upstream conveying means 3 and the reversing means 5TC are arranged facing each other with their conveying surfaces spaced a predetermined distance apart in the boundary region BR on the conveying path. The gap δ between the reversing means 5T and the downstream conveying means 5 is smallest when the intake port 52a of the rotating drum 52 faces the 6 o'clock direction, and at subsequent rotation angles, it increases as the rotating drum 52 rotates.

[0156] According to the inventors' investigations, in order to reliably adsorb tablet T when transferring tablet T from the upstream conveying means 3 to the downstream conveying means 5 at a position where the gap δ is smallest, it has been found that the angle at which suction by the rotating drum 52 begins when the transfer operation is started is preferably offset upstream by a few degrees from the rotation angle at which the air intake 52a faces the 6 o'clock direction.

[0157] In contrast, the device 1C is configured to operate the posture control mechanism 7 to change the rotation angle range within which the rotating drum 52 can suck in air through the intake port 52a. Therefore, with the device 1C, by adjusting the angle range to suit the characteristics of the tablet T, such as its shape and weight, it is possible to transfer the tablet T from the upstream conveying means 3 to the downstream conveying means 5 at a position where the gap δ is smallest.

[0158] It goes without saying that the offset angle and direction are not limited to those described above, and can be changed as appropriate depending on the target conditions such as the shape, weight, and diameter of the tablet, and the device conditions such as the conveying speed and suction strength.

[0159] <Effects> As described above, in device 1C, in addition to the configuration of device 1B, posture control mechanism 7C is configured to be able to change the start angle and end angle of the first rotation angle range by servo motor 75, and is characterized in that by changing the start angle and end angle, the predetermined direction in which air intake 52a in rotating drum 52 faces when it begins suction is changed.

[0160] With this configuration, the height of the rotating drum 52 relative to the upstream conveying means 3 can be changed, the gap δ between the inversion means 5TC and the upstream conveying means 3 can be freely adjusted to suit the thickness of the target tablet T, and the rotation angle range in which the rotating drum 52 can suck air through the intake port 52a can be changed, allowing the device to be set to the optimal angle range to suit the characteristics of the tablet T.

[0161] This makes it possible to suppress positional deviation and tilt of the tablets T on the conveying path in the process of transferring the tablets T from the upstream conveying means 3 to the downstream conveying means 5C when printing on tablets T of different thicknesses.

[0162] Furthermore, according to the device 1C, it is possible to adsorb the tablet T under optimal conditions, for example, when the tablet T being transported tends to be transported in an inclined state, such as with one of the front and rear ends lowering and the other raising along the transport direction.

[0163] <<Variations>> Although the tablet printing apparatus according to the embodiment has been described, the present disclosure is not limited to the above embodiment except for its essential characteristic components. For example, the present disclosure also includes forms obtained by applying various modifications to the embodiments that a person skilled in the art can think of, and forms realized by arbitrarily combining the components and functions in each embodiment within the scope of the present invention. Below, a modified example is described as an example of such a form.

[0164] In the device 1C according to the third embodiment described above, as an example of the attitude control mechanism 7 for changing the rotation angle range in which suction is possible, a configuration has been shown in which the drive of the servo motor 75 is transmitted to the driven pulley 71 attached to the hollow shaft 55 by a toothed belt 73. However, the means for transmitting the drive force to the hollow shaft 55 that determines the rotation angle range in which suction is possible of the rotating drum 52 is not limited to the above and may be changed as appropriate.

[0165] As a modified example of the third embodiment, for example, the servo motor 75 may be arranged close to the fixed shaft 55, and the fixed shaft 55 may be rotated by the servo motor 75 via a reducer using gears. In this case, the output shaft of the servo motor 75 may be arranged coaxially with the hollow shaft 55, and the rotation angle of the hollow shaft 55 may be changed by reducing the speed using a planetary gear mechanism. With a more compact configuration, the device can be set to an optimal angle range according to the characteristics of the tablet T, such as the shape and weight.

[0166] Fourth Embodiment The devices 1A, 1B and 1C according to the above embodiments 1 to 3 are equipped with a tablet supply section 2, an upstream conveying means 3, an upstream printing section 4U, and downstream conveying means 5, 5B and 5C having inversion means 5T, 5TB and 5TC and downstream linear conveying means 5L and 5LB, and are configured so that information is printed on the front and back surfaces of the tablets T as the tablets T supplied from the tablet supply section 2 are transported along a path consisting of the upstream conveying means 3 and the downstream conveying means 5, 5B and 5C.

[0167] In contrast, the tablet printing device 1D according to embodiment 4 (hereinafter, sometimes referred to as "device 1D") is a tablet printing device equipped with a function of circulating and transporting tablets T within the device, and differs from the devices according to embodiments 1 to 3 in that some of the tablets T transported along a path consisting of an upstream transport means and a downstream transport means are returned to the tablet supply section and circulated along the path, and the device has a function of being able to increase or decrease the amount of tablets T transported along the path by controlling the supply and return. Such device 1D makes it possible to efficiently change the settings of the device when changing the type of tablets T, etc.

[0168] <Configuration of tablet printing device 1D> The device 1D according to the fourth embodiment will be described in detail below with reference to the drawings. Figure 13 is a front view showing the general configuration of device 1D relating to embodiment 4, Figure 14 is a plan view of the tablet supply section 2, upstream printing section 4U and discharge and conveying means 9 in device 1D viewed from above, and Figure 15 is a cross-sectional view of device 1D taken along line A5-A5 in Figure 13.

[0169] (Overall composition) As shown in Figures 13 to 15, the device 1D comprises a base 1 that supports each part, has an interior space 1a of the equipment on its rear side, and functions as the front panel of the housing, a tablet supply unit 2D that supplies tablets T, an upstream conveying means 3 that transports the supplied tablets, an upstream printing unit 4U that prints information on the tablets T transported by the upstream conveying means 3, a downstream conveying means 5D arranged downstream of the upstream conveying means 3, a downstream printing unit 4D that prints information on the tablets T transported by the downstream conveying means 5D, a non-defective product extraction unit 8 arranged downstream of the downstream printing unit 4D, a discharge conveying means 9 that discharges non-defective products, a tablet return unit 120 that returns the transported tablets T to the tablet supply unit 2D, a print defect sorting unit 220 that sorts out tablets T with print defects and removes them from the system, and a control means 10D that controls these elements.

[0170] (Outline of each part) Below, an overview of the configuration of each part in the device 1D will be described. In the device 1D, the base 1, the upstream conveying means 3, the upstream printing unit 4U, the downstream printing unit 4D, the non-defective product extraction unit 8, and the discharge conveying means 9 have the same configuration as the device 1B shown in Fig. 2. Therefore, these components are given the same numbers as in the device 1B and their explanations are omitted. Below, the configurations of the tablet supplying unit 2D, the downstream conveying means 5D, the tablet return unit 120, the print defect sorting unit 220, and the control means 10D will be mainly described.

[0171] [Tablet supply unit 2D] The tablet supply unit 2D is a mechanism unit that measures and controls the number of tablets T supplied, and also arranges the supplied tablets T into a single row and supplies them to the upstream conveying means 3, and is different from the tablet supply unit 2 in that it has a function of measuring the quantity of tablets T supplied. As shown in Figs. 13 to 15, the tablet supply unit 2D is configured to include a hopper 21, a linear feeder 23, a passing detection unit 24, a connection lane 25, a ball feeder 26, and a supply lane 27. In this example, as in the first to third embodiments, the upstream conveying means 3 is configured to convey the tablets T using two conveying belts 33 arranged in parallel, so that the linear feeder 23, the passing detection unit 24, the connection lane 25, the ball feeder 26, and the supply lane 27 in the tablet supply unit 2D are arranged one by one corresponding to each of the two conveying belts 33.

[0172] The hopper 21 is disposed on the base 1 and is a funnel-shaped mechanism that receives a large number of tablets T from above and drops the tablets T (arrow T21 in Figures 13 and 15) to the base end 23a of the linear feeder 23 located below.

[0173] The linear feeder 23 is a conveyor that places and conveys a plurality of tablets T supplied from the hopper 21 on a plurality of parallel conveying paths, and determines the number of tablets T to be supplied to the downstream bowl feeder 26. In this example, the linear feeder 23 is arranged such that the two linear feeders 23 extend in different directions from the base end 23a below the hopper 21 in a plan view. Each linear feeder 23 has a plurality of parallel conveying paths 231 (seven in this example) arranged in parallel, and the tablets T supplied from the hopper 21 to each linear feeder 23 are approximately evenly distributed to the plurality of conveying paths 231 and conveyed in a straight line (arrow T23 in FIGS. 14 and 15).

[0174] The passage detection unit 24 is a tablet passage detection means that is disposed at the end 23b of each linear feeder 23, has a plurality of openings 24a that receive and pass tablets T discharged from each of the plurality of conveying paths 231 (arrow T24 in Figs. 13 and 15), and has a passage sensor (not shown) made of, for example, an optical sensor disposed at each opening 24a. The passage detection unit 24 detects the passage of tablets T discharged from the plurality of conveying paths 231 in each linear feeder 23, and outputs the detection result to the control unit 11D, which counts the number of tablets T supplied from each linear feeder 23, and adjusts the conveying speed of the linear feeder 23 so that the number of tablets T supplied becomes a predetermined value. This specifies the number of tablets T to be supplied to the subsequent bowl feeder 26.

[0175] The connection lane 25 is an inclined conveying path that is disposed below each of the passage detection units 24 and collects tablets discharged from the passage detection units 24 and conveys them to the downstream bowl feeder 26 (arrow T25 in FIGS. 13 and 14).

[0176] The bowl feeder 26 is a mechanism unit that rearranges and outputs tablets T in a line. As shown in Figs. 14 and 15, the bowl feeder 26 has a cone-shaped rotating member 261 that rotates around a central axis 26o, and a spiral blade 262 that is arranged in a rotationally fixed state on the inclined surface of the inner wall of the cone-shaped rotating member 261. In the bowl feeder 26, the cone-shaped rotating member 261 rotates around the central axis 26o (arrow R26 in Fig. 14), and thus a plurality of tablets T filled inside the cone-shaped rotating member 261 are pushed outward in the radial direction of the cone-shaped rotating member 261 by the spiral blade 262 (arrow T26 in Fig. 15) and arranged in a single line along the outer periphery 261a. Then, the tablets T are sequentially supplied to the supply lane 27 connected to a predetermined position of the outer periphery 261a.

[0177] The supply lane 27 is a conveyor disposed between the bowl feeder 26 and the upstream conveying means 3, which sequentially conveys the tablets T discharged in a single line from the bowl feeder 26 to the conveying belt 33 of the upstream conveying means 3 at predetermined intervals (arrow T27 in Figures 13 and 14).

[0178] [Downstream conveying means 5D] The downstream conveying means 5D includes an inverting means 5TB that inverts the conveying direction of the tablet T in the upstream conveying means 3 from a first direction D1 (arrow T1 in FIG. 13) to a second direction D2 (arrow T2 in FIG. 13), and a downstream linear conveying means 5LB that is located downstream of the inverting means 5TB in the conveying path and linearly conveys the inverted tablet T in the second direction D2 (arrow T3 in FIG. 13). In a state in which the tablet T is being conveyed by this downstream linear conveying means 5LB, printing is performed on one surface of the tablet T facing upward by the downstream printing unit 4D. This configuration is the same as that of the downstream conveying means 5B according to the second embodiment.

[0179] As shown in Fig. 13, the downstream conveying means 5D further includes downstream linear conveying means 5LD in a section between the pulley 51 of the downstream linear conveying means 5LB and the pressure pulley 54. The downstream linear conveying means 5LD linearly conveys the tablet T conveyed to the drive side pulley 51 in a first direction D1 while sucking it (arrow T7 in Fig. 13).

[0180] Specifically, the downstream linear conveying means 5LD includes a pulley 511 arranged to face the drive-side pulley 51 of the downstream linear conveying means 5LB with a predetermined gap therebetween, a pulley 512 arranged with a predetermined gap in the X-direction from the pulley 511, and a conveying belt 513 suspended therebetween. The pulleys 511 and 512 form a pair of a driving pulley and a driven pulley. Furthermore, a pressing pulley 514 for determining the position of the conveying belt 33 with respect to the conveying belt 513 may be provided.

[0181] According to the downstream conveying means 5D, the tablet T linearly conveyed (arrow T3) in the second direction D2 by the downstream linear conveying means 5LB is, for example, adsorbed and held by the conveying belt 33 wound around the circumferential surface of the pulley 51 by a suction means built in the pulley 51, rotates around the pulley 51, and then is released from adsorption below the pulley 51 and transferred onto the conveying belt 513 of the opposing downstream linear conveying means 5LD. Then, the tablet T is placed on the conveying belt 513 of the downstream linear conveying means 5LD and linearly conveyed in the first direction D1 to a predetermined position (arrow T7 in FIG. 13).

[0182] [Tablet Return Department 120] The tablet return section 120 is a mechanism unit for returning the transported tablets T to the tablet supply section 2D. The tablet return section 120 is, for example, arranged on the transport path of the downstream linear transport means 5LD, and is composed of a tablet return mechanism 121 that transfers the tablets T from the downstream linear transport means 5LD to the bowl feeder 26. The tablet return mechanism 121 drops the tablets T that have been transported on the transport path of the downstream linear transport means 5LD and passed through the pulley 511, via an inclined passage (not shown), into the bowl feeder 26 below, and transfers them (arrow T81 in FIG. 13).

[0183] Alternatively, the tablet return section 120 may be, for example, a tablet return mechanism 122 that is disposed on a conveying path on the circumferential surface of the pulley 51 of the downstream linear conveying means 5LB and transfers the tablets T from the downstream linear conveying means 5LB to the hopper 21. In this case, the tablet return mechanism 122 ejects air from the side toward the tablets T on the conveying path on the circumferential surface of the pulley 51, thereby causing the tablets T to drop and be transferred to the hopper 21 below (arrow T82 in FIG. 13).

[0184] [Print Defects Sorting Department 220] The print defect sorting unit 220 is a mechanism unit that is disposed after the downstream printing unit 4D on the conveying path of the downstream linear conveying means 5LB, and sorts out tablets T related to defective products whose print quality on at least one of the front and back sides does not meet a predetermined printing standard, and discharges them from the downstream conveying means 5D to the outside of the system. As described above, the print quality of the front and back sides of the tablets T is judged by the control means 10D based on the images of the tablets T after printing captured by the inspection image capturing units 43U and 43D. When the print quality of the front and back sides of the target tablets T does not meet the predetermined printing standard, the print defect sorting unit 220 ejects air blow, for example, from the side, at the tablets T on the conveying path of the downstream linear conveying means 5LB based on the instruction of the control means 10D, thereby dropping the tablets T downward and discharging them to the outside of the system (arrow T5 in FIG. 13).

[0185] [Control means 10D] The control means 10D is a circuit that is electrically connected to the tablet supplying unit 2D, upstream conveying means 3, upstream printing unit 4U, downstream conveying means 5D, downstream printing unit 4D, non-defective product extraction unit 8, discharge conveying means 9, tablet return unit 120, and defective print sorting unit 220, and outputs control signals to control the operation of each unit. The control means 10D is made up of a control unit 11D that acquires signals from each unit and issues control signals to these units, and a drive unit 12D that passes current through drive means such as motors and piezoelectric elements in each unit based on the control signals to operate them.

[0186] The control unit 11D is realized, for example, as a computer having a general CPU and RAM, and programs executed by these, and realizes the functions of the device 1D by reading a control program related to the device 1D from a storage device or the like into the RAM and executing it.

[0187] The drive unit 12D is composed of various motors that operate the tablet supply unit 2D, the upstream conveying means 3, the downstream conveying means 5D and the discharge conveying means 9, the print heads of the upstream printing unit 4U and the downstream printing unit 4D, the upstream conveying means 3, the downstream conveying means 5 and the non-defective product extraction unit 8, the tablet return unit 120, and a drive circuit for driving the electromagnetic air valve in the defective print sorting unit 220.

[0188] The control means 10D realizes the following functions of the device 1D. (1) In the device 1D, the tablet return section 120 can transfer and return some or all of the tablets T transported through the upstream conveying means 3 and the downstream conveying means 5D to the tablet supply section 2D, thereby enabling the tablets T to be circulated along a path formed by the upstream conveying means 3 and the downstream conveying means 5D.

[0189] (2) The tablet supplying section 2D having the linear feeder 23 can increase or decrease the number of tablets T supplied to the upstream conveying means 3 per unit time, thereby making it possible to supply a predetermined number of tablets T.

[0190] (3) By using the print defect sorting unit 220 to sort tablets T and discharge them outside the system, the total number of tablets T circulating within the device 1D through the upstream conveying means 3 and the downstream conveying means 5D can be adjusted.

[0191] With this function, the device 1D can automate the adjustment operation of the device setting conditions when the type of tablet T is changed, for example.

[0192] <Device 1D Operation> The operation of the device 1D having the above configuration will now be described. The device 1D performs a tablet printing operation of printing information on the front and back surfaces of the tablets T transported along the transport path by transporting the tablets T supplied from the tablet supply unit 2 along a path consisting of the upstream transport means 3 and the downstream transport means 5D. The tablet printing operation is similar to that of the devices 1A, 1B, and 1C according to the above-mentioned embodiments 1 to 3, and therefore a description thereof will be omitted.

[0193] The device 1D is configured to have a function of circulating and transporting tablets T to be printed as an operation other than tablet printing operation, and performs an operation in which some or all of the tablets T supplied and transported along a path consisting of the upstream transport means 3 and downstream transport means 5D are returned to the tablet supply unit 2D and circulated along the path. Furthermore, the device 1D performs an operation to increase or decrease the total number of tablets T transported along the path by controlling the number of tablets T supplied, returned, and discharged per unit time in the control unit 11D, thereby adjusting the transport speed, etc.

[0194] The following will explain an overview of the adjustment operation of the conveying speed in the apparatus 1D. Fig. 16 is a flow chart showing an overview of the adjustment operation of the conveying speed in the apparatus 1D.

[0195] First, the control means 10D operates the tablet supply unit 2D, the upstream conveying means 3, and the downstream conveying means 5D (step S11), and then sets the number of tablets supplied per unit time based on the conveying speed of the linear feeder 23 (hereinafter sometimes referred to as the "supply number") and the allowable maximum number of tablets T returned from the tablet return unit 120 to the tablet supply unit 2D (hereinafter sometimes referred to as the "maximum return number") to initial values ​​smaller than their respective reference values ​​(step S12). With this setting, the pitch of the tablets T becomes a value larger than the upper limit value described later. Note that the supply number and the maximum return number may be set to equivalent values.

[0196] Next, based on a passing detection signal of the tablets T outputted from the detection means 34 disposed at a predetermined position on the conveying path, pitch data between successive tablets T on the conveying path is calculated (step S13).

[0197] Here, the pitch data is the ratio of the pitch of consecutive tablets T to the average length of tablets T in the conveying direction, and the average length may be, for example, the diameter when the shape of tablets T in a plan view is circular, the average of the diameter and the minor axis when the shape is elliptical, or the average of the width and length when the shape is other than a circle. In addition, the pitch data calculated in step S13 may be the average value or the minimum value of a plurality of pitch data calculated from the passing times of consecutive tablets T on the conveying path within a predetermined time. The reference value of the pitch data may be, for example, 1.7 or more and 2.3 or less with respect to the above-mentioned average length in the conveying direction of tablets T. In addition, in this case, the lower limit of the reference value of the pitch data is 1.7, the upper limit is 2.3, and the median is 2.0.

[0198] Next, it is determined whether the pitch data is below the upper limit value (step S14), and if it is greater than the upper limit value (No), the number of supplies and the maximum number of returns are gradually increased (step S15) to reduce the pitch of tablets T, and the process returns to step S13 to calculate the pitch data. If the pitch data is below the upper limit value (Yes), the process proceeds to step S16.

[0199] In step S16, it is determined whether the pitch data is less than the lower limit value. If the pitch data is equal to or greater than the lower limit value (No), the number of tablets supplied and the maximum number of tablets returned are gradually increased (step S15) to reduce the pitch of the tablets T, and the process returns to step S13 to calculate the pitch data. If the pitch data is less than the lower limit value (Yes), the process proceeds to step S18.

[0200] Next, the supply quantity and the maximum return quantity are set to optimal values ​​(step S17), and the process ends. The optimal values ​​of each variable may be set to, for example, the average or median of the two set values ​​based on the set values ​​when the judgments in steps S14 and S16 are both Yes. This completes the adjustment of the transport speed in the apparatus 1D.

[0201] <Small summary> As described above, the tablet printing apparatus 1D according to the fourth embodiment is a tablet printing apparatus capable of printing information on the front and back surfaces of tablets transported along a transport path including an upstream transport means 3 and a downstream transport means 5D, and includes a tablet supplying section 2D that supplies tablets T, an upstream transporting means 3 that transports the supplied tablets, an upstream printing section 4U that prints information on tablets T transported by the upstream transporting means 3, a downstream transporting means 5D disposed downstream of the upstream transporting means 3, and a tablet printing section 4U that prints information on tablets T transported by the downstream transporting means 5D. The system is equipped with a downstream printing unit 4D that prints information on the tablets T that are transported, a non-defective product extraction unit 8 arranged downstream of the downstream printing unit 4D, a tablet return unit 120 that returns the transported tablets T to the tablet supply unit 2D, a print defect sorting unit 220 that sorts out tablets T with printing defects and removes them from the system, and a control means 10D that controls these elements, and the tablets supplied from the tablet supply unit 2D are configured to be transported in a circular manner along a route that passes through the upstream conveying means 3, the downstream conveying means 5D and the tablet return unit 120 and returns to the tablet supply unit 2D.

[0202] Conventionally, adjustment of the setting conditions of a tablet printing device due to changes in tablet types, etc., was performed by the operator manually repeating one-way conveyance under different setting conditions, for example by receiving tablets once conveyed through the device in a container, returning them manually to the tablet supply unit, changing the setting conditions, and repeating the tablet conveyance. Therefore, there were issues such as the time required for setting and adjustment work, and the need to perform setting and adjustment work depending on the experience and intuition of the operator while checking the mutual balance between the tablet supply unit - upstream conveying means - downstream conveying means.

[0203] In contrast, as described above, the tablet printing apparatus 1D according to the fourth embodiment has a function for circulating and transporting the tablets T on a route including the upstream transport means 3 and the downstream transport means 5D, and a function for controlling the number of tablets supplied and the maximum number of tablets returned, thereby realizing automation of the operation for adjusting the pitch of the tablets T on the transport route to an optimal value by increasing or decreasing the total number of tablets T on the route. As a result, it is possible to automate the adjustment of the setting conditions of the apparatus 1D accompanying a change in the type of tablets T, and the efficiency of the change of the setting conditions of the apparatus can be greatly improved.

[0204] Fifth Embodiment A tablet printing apparatus 1E according to embodiment 5 (hereinafter, may be referred to as "apparatus 1E") will be described below.

[0205] <Configuration of the tablet printing device 1E> In the device 1D of embodiment 4, the tablet supply unit 2D measures and controls the quantity of tablets T supplied by the linear feeder 23, arranges the tablets T in a single row by the ball feeder 26, and then sequentially supplies them to the upstream conveying means 3 via the supply lane 27.

[0206] In contrast, device 1E according to embodiment 5 differs from device 1D according to embodiment 4 in that it is provided with a configuration in which a tablet supply unit and control means detect chipped tablets or tablets with abnormal shapes and prevent abnormal tablets from being supplied to the upstream conveying means 3, but the other configurations are the same as those of device 1D shown in Fig. 13. Therefore, the following will mainly outline the configurations of the tablet supply unit in device 1E and the control means that controls it, and will not describe the other configurations.

[0207] <Configuration of tablet supply unit 2E and control means 10E> The above configuration of the device 1E will be described below with reference to the drawings. Fig. 17(a) is a plan view showing an outline of the configuration of the tablet supplying section 2E and the control means 10E in the device 1E, and (b) is a cross-sectional view of the tablet supplying section 2E taken along line A6-A6 in (a). Figs. 18(a) and (b) are diagrams for explaining an outline of the selective removal operation of abnormal tablets to be supplied in the tablet supplying section 2E.

[0208] The tablet supply unit 2E is a mechanism unit that measures and controls the number of tablets T supplied, and also arranges the supplied tablets T into a single row and supplies them to the upstream conveying means 3 (not shown). It is configured with a hopper 21, a linear feeder 23, a passing detection unit 24, and a connection lane 25 (part of which is shown in FIG. 17(a)), which are not shown in FIG. 17(a)(b), and a ball feeder 26, a supply lane 27, an abnormal tablet removal unit 28, and an accumulated tablet dispensing guide 29, which are shown in FIG. 17(a)(b). Of these elements, in the device 1E, the hopper 21, the linear feeder 23, the passing detection unit 24, the connection lane 25, the ball feeder 26, and the supply lane 27 have the same configuration as the tablet supply unit 2D shown in FIG. 13 to 15. Therefore, these configurations are assigned the same numbers as the tablet supply unit 2D and their explanations are omitted, and the following mainly describes the configurations of the abnormal tablet removal unit 28 and the accumulated tablet dispensing guide 29 in the tablet supply unit 2E.

[0209] Moreover, in addition to the same configuration and functions as the control means 10D of the device 1D, the control means 10E is configured to include a control unit 11E having a function of controlling the operation of selectively removing abnormal tablets to be fed, and a drive unit 12E having a function of driving the tablet feed unit 2E. Therefore, the configuration related to the selective removal function of abnormal tablets to be fed in the control means 10E will be described below.

[0210] [Abnormal Tablet Rejection Division 28] The abnormal tablet removal unit 28 is a mechanism unit that detects and removes tablet fragments or tablets having abnormal shapes in the tablet supply unit 2E. As shown in Figures 17(a) and (b), the abnormal tablet removal unit 28 is composed of an imaging unit 281 and an air ejection unit 282.

[0211] The imaging unit 281 is an image acquisition means disposed facing the circumferential flat area 261b (hereinafter, sometimes referred to as the "circumferential flat area") inside the outer periphery 261a of the cone-shaped rotating member 261 of the bowl feeder 26 through a predetermined gap, and acquires an image of the tablets T to be fed arranged in a single row along the outer periphery 261a of the bowl feeder 26 viewed from above in a plan view, as shown in FIG. 18(a). For example, a two-dimensional imaging element can be used for the imaging unit 281. The acquired image of the tablets to be fed is output to the control unit 11E, and the control unit 11E extracts the contour of the tablet image from the image, and determines whether the tablets to be fed are fragments or not based on the shape of the detected contour, or whether the tablets have an abnormal shape.

[0212] The air blowing unit 282 is a mechanism unit that is disposed outside the outer periphery 261a of the cone-shaped rotating member 261 of the bowl feeder 26 and blows air toward the radially inward direction of the cone-shaped rotating member 261. When the control unit 11E determines that the tablet to be fed is a fragment or has an abnormal shape, the air blowing unit 282 blows air from the side of the tablet before it is fed to the feed lane 27 based on a signal emitted from the drive unit 12E, as shown in FIG. 18(b), thereby causing the tablet to fall to the center of the cone-shaped rotating member 261 (arrow T28 in FIG. 18(b)). This prevents abnormal tablets from being fed to the upstream conveying means 3.

[0213] In this way, in device 1E, the rejected abnormal tablets to be fed are returned to the center of cone-shaped rotating member 261 of bowl feeder 26 and accumulated there, and the ratio of accumulated abnormal tablets increases as device 1E is operated, and the number of tablets T fed from tablet supply unit 2E decreases. Therefore, the abnormal tablets accumulated in ball feeder 26 are dispensed and discharged outside ball feeder 26 during regular maintenance of device 1E, etc.

[0214] [Accumulated Tablet Dispensing Guide 29] Accumulated tablet dispensing guide 29 is arranged on the outer peripheral edge 261a of funnel-shaped rotating member 261 of ball feeder 26, and is a radially movable guide mechanism which dispenses abnormal tablets accumulated in ball feeder 26, such as during regular maintenance of device 1E, and discharges them radially outward from ball feeder 26, with tip portion 29a close to center 26o of ball feeder 26 entering outer peripheral flat area 261b.

[0215] As shown in FIG. 17, the accumulated tablet dispensing guide 29 has a configuration including a discharge guide portion 291 and a movable peripheral portion 292 extending radially inward of the discharge guide portion 291.

[0216] The discharge guide portion 291 is inclined in the conveying direction of the tablets T so as to move away from the outer circumferential edge 261a of the bowl feeder .

[0217] The movable peripheral portion 292 is located on an arc on the outer peripheral edge 261a of the bowl feeder 26 when the accumulated tablet dispensing guide 29 is located radially outward. In addition, a hole or notch 261c is opened in the outer peripheral edge 261a of the bowl feeder 26 at a position overlapping with the movable peripheral portion 292. The movable peripheral portion 292 is configured to close the hole or notch 261c when the accumulated tablet dispensing guide 29 is located at the outermost radial position, and functions as the outer peripheral edge 261a that transfers the tablet T along the outer peripheral edge 261a. The discharge guide portion 291 and the movable peripheral portion 292 may be formed integrally.

[0218] Figures 19(a) and (b) are figures explaining an overview of the dispensing operation of accumulated tablets by the first mode of the tablet supply unit 2E, where the upper figure (a) is a plan view showing the mode during normal operation, the lower figure (a) is a cross-sectional view taken along A7-A7 in the upper figure (a), the upper figure (b) is a plan view showing the mode during dispensing operation, and the lower figure (b) is a cross-sectional view taken along A8-A8 in the upper figure (b).

[0219] Figures 20(a) and (b) are figures explaining an overview of the dispensing operation of accumulated tablets by the second mode of the tablet supply unit 2E, where the upper figure (a) is a plan view showing the mode during normal operation, the lower figure (a) is a cross-sectional view taken along A9-A9 in the upper figure (a), the upper figure (b) is a plan view showing the mode during dispensing operation, and the lower figure (b) is a cross-sectional view taken along A10-A10 in the upper figure (b).

[0220] 21(a) and (b) are diagrams for explaining an outline of the dispensing operation of accumulated tablets by the third mode of the tablet supplying unit 2E, where the upper diagram (a) is a plan view showing the mode during normal operation, the lower diagram (a) is a cross-sectional view taken along A11-A11 in the upper diagram (a), the upper diagram (b) is a plan view showing the mode during dispensing operation, and the lower diagram (b) is a cross-sectional view taken along A12-A12 in the upper diagram (b). Note that Figs. 19 to 21 show only one of a pair of components arranged corresponding to each of a pair of juxtaposed conveyor belts 33 in the tablet supplying unit 2E, with the other being omitted.

[0221] In the first mode of the tablet supply unit 2E, during normal operation, as shown in Fig. 19(a), the tip portion 29a of the accumulated tablet dispensing guide 29 (hereinafter, sometimes referred to as "dispensing guide 29") is retreated to the position of the outer circumferential edge 261a of the cone-shaped rotating member 261 of the bowl feeder 26, and the tablet T pushed out radially outward by the spiral blade 262 (arrow T26 in Fig. 19(a)) is transported along the outer circumferential edge 261a to the connection position of the supply lane 27 (arrow T27 in Fig. 19(a)). At this time, the movable peripheral portion 292 closes the hole or notch 261c and functions as a part of the outer circumferential edge 261a.

[0222] On the other hand, during the dispensing operation of the accumulated tablets, as shown in Fig. 19(b), the dispensing guide 29 enters inwardly in a radial direction to a position where it blocks the outer peripheral flat area 261b inside the outer peripheral edge 261a of the cone-shaped rotating member 261 of the bowl feeder 26. At this time, the movable peripheral part 292 of the dispensing guide 29 moves inwardly in a radial direction, so that the hole or notch 261c is opened. As a result, the tablet T that has been transferred in the outer peripheral flat area 261b along the outer peripheral edge 261a as the bowl feeder 26 rotates is discharged by the dispensing guide 29 to the outside of the cone-shaped rotating member 261 through the hole or notch 261c of the outer peripheral edge 261a (arrow T29 in Fig. 19(b)).

[0223] In the first mode of the tablet supply unit 2E, a configuration is adopted in which, before the dispensing guide 29 is advanced in the radially inward direction, the rotation of the spiral blade 262 is stopped to stop the supply of tablets T, and the mortar-shaped rotating member 261 is rotated for a certain period of time. As a result, all tablets T present in the outer peripheral flat region 261b are discharged to the outside of the bowl feeder 26 through the supply lane 27, and a state in which no tablets T are present in the outer peripheral flat region 261b is created. In this state, the dispensing guide 29 is advanced in the radially inward direction to perform a dispensing operation of the accumulated tablets, whereby only the tablets T accumulated in the mortar-shaped rotating member 261 can be discharged to the outside.

[0224] In the second mode of the tablet supplying unit 2E, unlike the first mode, dispensing guide 29 is fixed in a state of being inserted radially inward to a position where it blocks outer peripheral flat area 261b inside outer peripheral edge 261a of cone-shaped rotating member 261 of bowl feeder 26. Instead, the phase of spiral blade 262 mounted on the inner inclined surface of cone-shaped rotating member 261 is configured to be changeable between normal operation and dispensing operation of accumulated tablets.

[0225] Specifically, during normal operation, as shown in Figure 20(a), the tip portion 262a of the spiral blade 262 is located downstream in the rotation direction of the dispensing guide 29 (arrow R26 in Figure 20(a)), so that the tablet T pushed radially outward by the spiral blade 262 (arrow T26 in Figure 20(a)) is transported along the outer circumferential edge 26 to the connection position of the supply lane 27 without coming into contact with the dispensing guide 29 (arrow T27 in Figure 20(a)).

[0226] On the other hand, during the dispensing operation of the accumulated tablets, as shown in Figure 20(b), the tip portion 262a of the spiral blade 262 is located upstream in the rotation direction of the dispensing guide 29 (arrow R26 in Figure 20(b)), so the tablet T pushed radially outward by the spiral blade 262 (arrow T26 in Figure 20(b)) is discharged by the dispensing guide 29 to the outside of the mortar-shaped rotating member 261 (arrow T29 in Figure 20(b)).

[0227] At this time, as shown in Figures 20(a) and (b), a hole or notch 261c is formed in the peripheral wall of the outer circumferential edge 261a of the mortar-shaped rotating member 261 at a location where it overlaps with the movable peripheral portion 292 of the dispensing guide 29, and during the dispensing operation of the accumulated tablets shown in Figure 20(b), the tablet T is discharged radially outward through this hole or notch 261c.

[0228] The third mode of the tablet supplying unit 2E is configured to include a circumferential rotating member 261E consisting of a circumferential flat region near the inside of the outer periphery without the mortar-shaped portion of the mortar-shaped rotating member 261, instead of the mortar-shaped rotating member 261 of the bowl feeder 26 in the first mode. Also, instead of the spiral blade 262, it is configured to include an inclined rotating disk 263 whose central axis 263o related to rotation is inclined from the direction of the central axis 26o (Z direction) so that the connection position side of the supply lane 27 is higher.

[0229] In the third embodiment, as in the first embodiment, during normal operation, as shown in Fig. 21(a), the tip portion 29a of the dispensing guide 29 is retracted to the position of the outer peripheral edge 261Ea of the circumferential rotating member 261E of the bowl feeder 26, and the tablet T pushed out radially outward by the inclined rotating disk 263 (arrow T26 in Fig. 21(a)) is transported along the outer peripheral edge 261Ea to the connection position of the supply lane 27 (arrow T27 in Fig. 21(a)). At this time, as in the first embodiment, the movable peripheral portion 292 is in a state of blocking the hole or notch 261Ec and functions as a part of the outer peripheral edge 261Ea.

[0230] On the other hand, during the dispensing operation of the accumulated tablets, as shown in Fig. 21(b), the dispensing guide 29 enters inwardly in the radial direction to a position blocking the circumferential rotating member 261E inside the outer circumferential edge 261Ea of the circumferential rotating member 261E of the bowl feeder 26. At this time, the movable peripheral portion 292 of the dispensing guide 29 moves inwardly in the radial direction, and the blocked hole or notch 261Ec is opened. As a result, the tablet T that has been transferred inside the circumferential rotating member 261E along the outer circumferential edge 261Ea as the inclined rotating disk 263 rotates is discharged outward of the circumferential rotating member 261E by the accumulated tablet dispensing guide 29 (arrow T29 in Fig. 21(b)).

[0231] In the plan views of Figures 19(a) and 21(a), the gap between the cumulative tablet dispensing guide 29 and the outer peripheral edges 261a, 261Ea is clearly shown in a schematic manner in order to distinguish between the holes or notches 261c, 261Ec and the cumulative tablet dispensing guide 29 and the outer peripheral edges 261a, 261Ea; however, in the actual device 1E, the holes or notches 261c, 261Ec are formed so that there is almost no gap between the cumulative tablet dispensing guide 29 and the outer peripheral edges 261a, 261Ea.

[0232] In addition, instead of providing the dispensing guide 29 with a movable peripheral portion 292 that functions as part of the outer peripheral edge 261a of the ball feeder 26, a movable door for discharging accumulated tablets that opens only in the radially inward direction may be provided at the point on the outer peripheral edge 261a of the ball feeder 26 that overlaps with the movable peripheral portion 292 of the dispensing guide 29.

[0233] <Operation of Device 1E> The operation of the device 1E having the above configuration will now be described. The operation of the device 1E relating to tablet printing is similar to that of the devices 1A, 1B, and 1C according to the above-mentioned first to third embodiments, and therefore a description thereof will be omitted.

[0234] The device 1E performs an operation of detecting and selectively removing abnormal tablets to be fed, other than the tablet printing operation. The device 1E also performs an operation of dispensing abnormal tablets accumulated in the bowl feeder 26 during regular maintenance, etc.

[0235] [Selective ejection of abnormal tablets] The selective ejection operation of abnormal tablets in the device 1E will be outlined below. FIG. 22 is a flow chart showing an outline of the selective ejection operation of abnormal tablets related to the supply in the tablet printing apparatus 1E.

[0236] First, the imaging unit 281 captures an image of the tablets to be fed arranged in a single row along the outer circumferential edge 261a of the bowl feeder 26 as viewed from above (step S21), and outputs the image to the control unit 11E.

[0237] Next, the control unit 11E extracts the outline of the tablet image from the image (step S22), and judges whether the tablet to be fed is a fragment or not based on the shape of the detected outline, or judges whether the tablet has an abnormal shape (step S23). If the tablet has an abnormal shape (Yes), the tablet is dropped by the air ejection unit 282 from the area near the outer circumferential edge 261a of the ball feeder 26 to the center of the cone-shaped rotating member 261, and is not fed to the feed path toward the feed lane 27 (step S24), and returns to step S21. On the other hand, if the tablet does not have an abnormal shape (No), the tablet is fed directly to the feed path toward the feed lane 27, and it is judged whether the inspection is finished (step S25). If the inspection is not finished (No), the process returns to step S21, and if the inspection is finished (Yes), the process ends. This completes the selective discharge operation of abnormal tablets in the device 1E.

[0238] [Discharge of accumulated abnormal tablets] Next, an outline of the discharge operation of accumulated defective tablets by the device 1E in the first mode will be described below. Fig. 23 is a flow chart showing an outline of the discharge operation of accumulated defective tablets in the tablet supplying section 2E.

[0239] First, a steady operation is performed in which each unit of the device 1E is operated to print information on the front and back of the tablet T (step S31), and then it is determined whether or not a predetermined time has elapsed (step S32). If the predetermined time has not elapsed (No), the process returns to step S31, and if the predetermined time has elapsed (Yes), the process proceeds to step S33. In this state, the abnormal tablet removal unit 28 drops fragments of tablets to be fed and tablets to be fed having abnormal shapes from the area near the outer circumferential edge 261a of the bowl feeder 26 to the center of the cone-shaped rotating member 261, and the removed abnormal tablets to be fed are accumulated in the center of the cone-shaped rotating member 261.

[0240] Next, linear feeder 23 is stopped to stop tablet supply, and other units of device 1E continue to operate (referred to as "linear feeder supply stop operation", step S33), after which it is determined whether a predetermined time has elapsed (step S34), and if not (No), the process returns to step S33 to continue linear feeder supply stop operation, and if it has elapsed (Yes), the process proceeds to step S35. In this state, the proportion of abnormal tablets accumulated in the center of cone-shaped rotating member 261 of bowl feeder 26 is further increased due to the supply stop operation.

[0241] Next, the supply stop operation of the linear feeder 23 is ended (step S35), and the accumulated abnormal tablets are discharged (step S36). Specifically, the dispensing guide 29 of the bowl feeder 26 is inserted into the area near the outer periphery 26 of the bowl-shaped rotating member 261 of the bowl feeder 26, the bowl-shaped rotating member 261 is rotated, and the tablets T transferred along the outer periphery 261a are discharged along the dispensing guide 29 to the outside of the bowl-shaped rotating member 261.

[0242] Next, it is determined whether or not the operation is to be ended (step S37). If the operation is not to be ended (No), the process returns to step S31, and if the operation is to be ended (Yes), the process ends. This completes the discharge operation of the accumulated abnormal tablets.

[0243] <Small summary> As described above, the device 1E of embodiment 5 is a tablet printing device which prints information on the front and back of tablets transported along the transport path, and is equipped with an abnormal tablet removal section 28 in a tablet supply section 2D having a ball feeder 26, and the abnormal tablet removal section 28 detects whether or not the tablets to be supplied have fragments or abnormal shapes, and when it is determined that the tablet to be supplied has fragments or is a tablet having an abnormal shape, it causes the tablet to fall from the circular flat area near the inside of the outer periphery 261a of the ball feeder 26 into the centre of the funnel-shaped rotating member 261 before being output to the supply lane 27, thereby preventing the abnormal tablet from being supplied to the upstream printing section 4U.

[0244] On the other hand, in device 1D, in tablet supply section 2D, the tablets to be supplied are arranged in a single row along outer circumferential edge 261a of bowl feeder 26, and then sequentially output to upstream conveying means 3 via supply lane 27. At this time, if tablet fragments or tablets with abnormal shapes are mixed in with the tablets to be supplied, clogging occurs in supply lane 27, which causes a problem of frequent stoppages of the device.

[0245] One possible solution to this problem is to detect tablet fragments or tablets with abnormal shapes while performing printing, and provide a discharge outlet or discharge passage to discharge them out of bowl feeder 26. However, since the tablets arranged in a single row are in contact with outer periphery 261a of bowl feeder 26, there is a concern that the tablets may get caught on the step on outer periphery 261a formed by the discharge outlet or discharge passage, preventing normal tablets from proceeding to supply lane 27.

[0246] In contrast, as described above, the device 1E of embodiment 5 is configured so that when the control unit 11E determines that the tablet to be supplied is a fragment or a tablet having an abnormal shape, the abnormal tablet removal unit 28 drops the tablet from the circular flat area near the inside of the outer circumferential edge 261a of the bowl feeder 26 into the center of the funnel-shaped rotating member 261 before it is output to the supply lane 27, thereby preventing the abnormal tablet from being output to the upstream conveying means 3.

[0247] This configuration makes it possible to avoid problems caused by providing discharge holes or discharge passages on the outer peripheral edge 261a of the bowl feeder 26, while suppressing the problem of frequent device stoppages due to blockages in the supply lane 27 caused by the inclusion of tablet fragments or tablets with abnormal shapes.

[0248] <Modification of device 1E> The device 1E of embodiment 5 is configured to detect and remove supply tablets having chipped or abnormal shapes using the abnormal tablet removal section 28, thereby preventing abnormal supply tablets from being output to the upstream conveying means 3.

[0249] In contrast, in a modified example of device 1E, the abnormal tablet removal unit 28 detects the presence or absence and angle of a score line on the top surface of the tablet to be supplied, and if a score line is detected on the top surface of the tablet to be supplied, information is printed on the front and back of the tablet based on the detection information, and if no score line is detected on the top surface of the tablet to be supplied, that is, if no score line is detected, the tablet is removed and returned to the abnormal tablet removal unit 28.

[0250] <Operation> An outline of the selective discharging operation of the score line undetectable tablets in the modified example of the device 1E will be described below. Fig. 24 is a flow chart showing an outline of the selective discharging operation of the score line undetectable tablets related to the supply in the modified example of the device 1E.

[0251] First, the imaging unit 281 captures an image of the tablets to be fed arranged in a single row along the outer circumferential edge 261a of the bowl feeder 26 as viewed from above (step S41), and outputs the image to the control unit 11E.

[0252] Next, the control unit 11E detects the presence or absence of a score line image in the tablet image portion from the acquired image (step S42), and determines whether or not a score line is detected on the upper surface of the tablet to be fed based on the presence or absence of the score line image (step S43). If no score line is detected on the upper surface (No), the air ejection unit 282 drops the score line undetected tablet from the area near the outer periphery 261a of the bowl feeder 26 to the center of the cone-shaped rotating member 261 (step S44), and returns to step S41. On the other hand, if a score line is detected on the upper surface (Yes), the tablet is fed to the feed lane 27 (step S45), and then determines whether or not score line detection is completed (step S46). If score line detection is not completed (No), the process returns to step S41, and if score line detection is completed (Yes), the process ends. This completes the selective discharge operation of the score line undetected tablets in the modified example of the device 1E.

[0253] <Small summary> As described above, the tablet printing device relating to the modified example of device 1E is a tablet printing device which prints information on the front and back of tablets transported along the transport path, and further comprises an abnormal tablet removal section 28 in addition to the tablet supply section 2D having a ball feeder 26, and if a score line is detected on the top surface of a tablet to be supplied, the abnormal tablet removal section 28 supplies the tablet to the supply lane 27 and prints information on the front and back of the tablet in the upstream printing section 4U and downstream printing section 4D, and if no score line is detected on the top surface of the tablet to be supplied, drops the tablet to the centre of the ball feeder 26 and returns it to the abnormal tablet removal section 28.

[0254] Generally, in the field of tablet printing, when information is printed on both sides of a tablet that has a score line on only one of the front and back sides, it is necessary to align the angles of the printing on the front and back sides with reference to the score line on one side to prevent the printed information on the front and back sides from being irregularly separated at places other than the specified positions after the tablet is divided along the score line.

[0255] For this reason, in conventional tablet printing devices, a measuring device or the like is used to measure the presence or absence of a score line on the front and back of the tablet and the angle of the score line before the printing process for the front and back sides, and then the positions of the front and back sides are aligned based on the obtained score line angle information to print the information.

[0256] However, in order to measure the presence or absence and angle of the score line on the front and back of the tablet prior to printing on the front and back, in addition to the conveying process for printing on the front and back, a tablet delivery and conveying mechanism for measuring the score line on the front and back is required, which poses the problem of reduced conveying accuracy and prone to conveying failure. In addition, a tablet delivery and conveying mechanism, a measuring camera, a sensor, etc. are required for measuring the score line, which complicates the device configuration of the tablet printing device and increases the device cost.

[0257] In contrast, the modified example of the device 1E according to the fifth embodiment is configured such that, when a tablet to be fed is determined to be a tablet with no score line detected on its upper surface, the abnormal tablet removal unit 28 drops the tablet from the circumferential flat area near the inner side of the outer periphery 261a of the bowl feeder 26 to the center of the cone-shaped rotating member 261 before feeding it to the feeding lane 27, thereby preventing the tablet with no score line detected from being fed to the upstream conveying means 3, and only the tablet with a score line detected is fed to the upstream conveying means 3. Furthermore, the tablet with no score line detected that has fallen to the center of the cone-shaped rotating member 261 is pushed outward in the radial direction by the spiral blade 262 of the bowl feeder 26 and arranged in a single row along the outer periphery 261a, and the abnormal tablet removal unit 28 measures again whether or not a score line is detected on the upper surface of the tablet to be fed, and if the tablet is a tablet with a score line detected, it is fed to the upstream conveying means 3 via the feeding lane 27.

[0258] With this configuration, when printing information on both sides of a tablet T that has a score line on only one of the front and back sides, a tablet printing function can be realized that aligns the angle of the information printing on the front and back sides with the score line on one side with a simple configuration that does not include a tablet delivery and transport mechanism for measuring the score lines on the front and back sides, a measurement camera, a sensor, etc. Also, by adopting a simple device configuration that does not include a mechanism for measuring the score lines on the front and back sides, it is possible to avoid the problems of reduced transport accuracy and transport failures that occur due to the complexity of the device configuration, and the problems of increased device costs.

[0259] Sixth Embodiment A tablet printing apparatus 1F (hereinafter, may be referred to as "apparatus 1F") according to embodiment 6 will be described below.

[0260] <Configuration of tablet printing device 1F> Apparatus 1F according to embodiment 6 is characterized in that a maintenance mechanism and an ink drip inspection mechanism are added to the upstream printing unit and downstream printing unit, and other configurations are the same as those of apparatus 1A, 1B, 1C or 1D shown in Figures 1, 6, 9 and 13. Therefore, the following mainly outlines the configurations of the upstream printing unit and downstream printing unit in apparatus 1F, and explanations of other configurations are omitted.

[0261] <Configuration of the upstream printing unit and downstream printing unit> The above configuration and operation of the device 1F will be described below with reference to the drawings. Figure 25(a) is a plan view alternatively showing the configuration of the upstream printing unit 14U or the downstream printing unit 14D in device 1F viewed in plan, explaining an overview of operation during normal operation, and (b) is a plan view alternatively showing the configuration of the upstream printing unit 14U or the downstream printing unit 14D in device 1F viewed in plan, explaining an overview of operation during maintenance operation, and Figures 26(a) and (b) are cross-sectional views showing the cross-sectional configuration of the upstream printing unit 14U and the downstream printing unit 14D in device 1F when cut along lines A13-A13 and A14-A14 in Figures 25(a) and (b), respectively.

[0262] The upstream printing unit 14U is disposed above the conveyor belt 33 between pulleys 31 and 32 of the upstream conveying means 3 on the base 1, and is a printing unit that prints on the upward facing surfaces of the front and back surfaces of the tablets T being conveyed.

[0263] The downstream printing unit 14D is arranged above the conveying belt 53 between the pulley 51 and the rotating drum 52 of the downstream linear conveying means 5L on the base 1, and is a printing unit that prints on the upward facing surfaces of the front and back surfaces of the tablets T being transported.

[0264] Each of the upstream printing unit 14U and the downstream printing unit 14D is configured to include, in this order from the upstream side to the downstream side of the transport path, a target image capturing unit 141, a print head 142, and an inspection image capturing unit 143. The configurations of the target image capturing unit 141, the print head 142, and the inspection image capturing unit 143 are the same as those of the target image capturing unit 41U or 41D, the print head 42U or 42D, and the inspection image capturing unit 43U or 43D in the device 1D, respectively, and therefore will not be described.

[0265] In the device 1F, the print head 142 is an inkjet type print head that performs non-contact printing on the upper surface of the tablet T being transported, and is disposed opposite the transport surface with a predetermined gap therebetween. The print head 142 has a plurality of linear nozzle rows in a direction perpendicular to the transport direction on a surface 142a (hereinafter sometimes referred to as the "nozzle surface") facing the transport belt 33 or 53. In this example, for example, a configuration is adopted in which four linear nozzles are arranged. According to the print head 142, ink is selectively ejected from the nozzles corresponding to the passing position of the tablet T in the Y direction according to the printing data in accordance with the passing time of the tablet T, and a predetermined pattern is printed on the upper surface of the tablet T.

[0266] The upstream printing unit 14U and the downstream printing unit 14D further include a linear motion mechanism 144 that moves the print head 142 in the Y direction to move it backward or forward relative to the base 1. During maintenance, the linear motion mechanism 144 is operated to move the print head 142 backward from above the conveyor belt 33 or 53, and then a purging operation is performed to clean the nozzles, or mechanical cleaning is performed by wiping the nozzle surface 142a with a cleaning blade made of, for example, a rubber member.

[0267] The upstream printing unit 14U and the downstream printing unit 14D further include a pair of passage detection sensors 145 for detecting the passing height of the nozzle surface 142a on both sides of the movement path of the print head 142 on the base 1 when it moves backward or forward. The passage detection sensor 145 can be, for example, a laser photoelectric sensor having multiple optical paths 145a arranged at a predetermined interval in the vertical direction, and is configured so that the nozzle surface 142a crosses some of the multiple optical paths 145a when the print head 142 moves backward or forward, and the passing height of the nozzle surface 142a can be measured by detecting which optical path 145a is blocked. This makes it possible to detect ink droplets or foreign matter adhering to the nozzle surface.

[0268] <Operation of Device 1F> The print head cleaning operation in the apparatus 1F having the above configuration will now be described.

[0269] Device 1F may perform a print head cleaning operation at the same time as the discharge operation of abnormal tablets accumulated in bowl feeder 26 in device 1E. Figure 27 is a flow chart showing an outline of the print head cleaning operation in device 1F. In Figure 27, steps S31 to S37 are the same as the operations in device 1E shown in Figure 23, so the same numbers are used and the explanation will be omitted.

[0270] In the device 1F, after the supply stop operation of the linear feeder 23 is completed in step S35, the accumulated abnormal tablets are discharged (step S36) and, in parallel, a print head cleaning operation is performed (step S38).

[0271] Specifically, in the print head cleaning operation (step S38), first, the linear motion mechanism 144 moves the print head 142 in the Y direction, and moves it backward relative to the base 1. At this time, the passage detection sensor 145 detects whether or not foreign matter such as ink droplets or tablet fragments is attached to the nozzle surface 142a by detecting which of the multiple optical paths 145a of the nozzle surface 142a is blocked.

[0272] Thereafter, after the print head 142 has moved to the rear of the base 1, a purging operation is performed to clean the nozzles of the print head 142. Furthermore, the nozzle surface 142a of the print head 142 may be mechanically cleaned by wiping it with, for example, a cleaning blade or the like.

[0273] Next, the print head 142 is moved in the Y direction by the linear motion mechanism 144, and advanced relative to the base 1. At this time, the passage detection sensor 145 detects whether or not ink droplets are attached to the nozzle surface 142a.

[0274] For example, if foreign matter such as tablet fragments adheres to the nozzle surface 142a during printing, the adhesion of the foreign matter may be detected when the print head 142 retracts, and mechanical cleaning may be performed by wiping it off using a cleaning blade or the like. Alternatively, if a large amount of ink is ejected by the purging operation and droplets adhere to the nozzle surface, the adhesion of the droplets may be detected when the print head 142 advances, and mechanical cleaning may be performed again using a cleaning blade to remove the droplets. By such a cleaning operation, ink droplets and foreign matter adhering to the nozzle surface 142a can be detected and removed. This completes the print head cleaning operation in the apparatus 1F.

[0275] <Small summary> As described above, the device F according to the sixth embodiment is provided with a linear motion mechanism 144 that moves the print head 142 in the Y direction in the upstream printing unit 14U and downstream printing unit 14D to move it backward or forward relative to the base 1, and a pair of passage detection sensors 145 for detecting the passing height of the nozzle surface 142a on both sides of the movement path of the print head 142 on the base 1 when it moves backward or forward. The passage detection sensor 145 is configured so that the nozzle surface 142a crosses some of the multiple optical paths when the print head 142 moves backward or forward, and is configured to measure the passing height of the nozzle surface 142a by detecting which optical path is blocked.

[0276] Conventionally, when ink drips onto the tablet transport path, only ink adhering to the top or bottom surface of tablet T that can be detected by the inspection image capturing unit 143 could be detected, and there was a problem that it was difficult for the defective printing sorting unit to remove tablets with ink adhering to the sides.

[0277] In contrast, the apparatus 1F according to the sixth embodiment is provided with the above-described configuration, and is therefore capable of detecting and removing ink droplets and foreign matter adhering to the nozzle surface 142a of the print head 142.

[0278] With this configuration, it is possible to reduce ink adhesion to areas other than the upper and lower surfaces of the tablet T that can be detected by the inspection image capturing unit 143, and it is possible to suppress the occurrence of defectively printed tablets in which ink adheres to areas other than the upper and lower surfaces of the tablet T, making it difficult for the defective printing sorting unit 220 to remove them.

[0279] Seventh Embodiment A tablet printing apparatus 1G (hereinafter, sometimes referred to as "apparatus 1G") according to embodiment 7 will be described below.

[0280] <Configuration of tablet printing device 1G> The device 1G according to the seventh embodiment is characterized in that it has been provided with a print defect sorting unit for analyzing and recording the discharging operation of tablets related to print defects, and other configurations are the same as those of the device 1D shown in Fig. 13. Therefore, the following mainly describes the configuration of the print defect sorting unit in the device 1G, and the description of other configurations will be omitted.

[0281] <About the composition of the print defect sorting unit> The above configuration and operation of the device 1G will be described below with reference to the drawings. The print defect sorting unit 220 is a mechanism unit that is disposed after the downstream printing unit 4D on the conveying path and discharges tablets T related to defective products whose print quality on at least one of the front and back sides does not meet a predetermined printing standard from the downstream conveying means 5 to the outside of the system. As described above, the print quality of the front and back sides of the tablets T is judged by the control means 10 based on the printed object images captured by the inspection image capturing units 43U and 43D. When the print quality of the front and back sides of the target tablets T does not meet the predetermined printing standard, the print defect sorting unit 220 drops the tablets T on the conveying path of the downstream linear conveying means 5L downward and discharges them to the outside of the system based on the instruction of the control means 10 (arrow T5 in FIG. 13).

[0282] Fig. 28 is a plan view showing an outline of the configuration of the print defect sorting unit 220 in the device 1G according to embodiment 7, Fig. 29 is a front view, and Fig. 30 is a sectional view of the print defect sorting unit 220 taken along line A15-A15 in Fig. 28. Fig. 31 is a plan view explaining the tablet discharge operation related to print defects.

[0283] As shown in FIG. 28, the print defect sorting section 220 is configured by arranging three print defect discharge mechanisms 220a, 220b, 220c (hereinafter, collectively referred to as "print defect discharge mechanisms 220x") in the corresponding order on each of two parallel conveying belts 53 of the downstream linear conveying means 5L.

[0284] The defective print ejection mechanism 220x includes an imaging unit 221, an air ejection unit 222, and a guide plate 223.

[0285] The imaging unit 221 is an image acquisition means disposed opposite to the upper surface of the conveyor belt 53 via a predetermined gap, and acquires a moving image showing in plan view the manner in which the tablets T placed on the conveyor belt 53 are discharged. For example, a high-speed camera of 1000 fps using a two-dimensional imaging element can be used for the imaging unit 221. The acquired moving image of the tablet is output to the control unit 11E, and it is determined whether or not the discharging operation for the target tablet is normal.

[0286] The air ejection unit 222 is a mechanism unit disposed, for example, on the side of the conveyor belt 53, and ejects an air blow toward the tablet T on the conveyor belt 53. When the control unit 11E determines that a tablet is a tablet related to a printing defect based on the images acquired by the inspection image capturing units 43U and 43D, the air ejection unit 222 ejects an air blow from the side toward the tablet T at a timing that coincides with the passage of the tablet T conveyed by the conveyor belt 53 based on a control signal issued from the drive unit 12E, as shown in FIG. 31, thereby blowing the tablet off and dropping it from the conveyor belt 53.

[0287] The guide plate 223 is a grooved angle-shaped cover member arranged opposite to the direction of the air blow, and receives the tablets T blown away by the air blow and drops them downward. As a result, the guide plate 223 discharges the tablets T related to the printing defect to the outside of the system.

[0288] The print defect discharge mechanisms 220a, 220b, and 220c are configured such that the air ejection units 222 arranged therein are selectively operated according to the type of print defect detected based on the images captured by the inspection image capturing units 43U and 43D. As a result, the tablets related to the print defect are classified according to the type of print defect and discharged by the guide plates 223 arranged in each of the print defect discharge mechanisms 220a, 220b, and 220c.

[0289] The control unit 11E extracts the center of gravity position of the tablet image from the image of each frame from the moving image of the tablet, and calculates a trajectory related to the discharge of the target tablet T based on the time-series change in the center of gravity position of the tablet T, as shown in Fig. 31. Then, by judging whether or not the trajectory related to the discharge is included in a predetermined range, it judges whether or not the discharge operation of the target tablet T is normal.

[0290] <Operation of device 1G> The device 1G is configured to include the above-described print defect sorting unit 220 as an operation other than tablet printing operation, and performs an analysis and recording operation of tablet discharge related to print defects.

[0291] [Analysis and recording of tablet discharge due to printing defects] The operation of analyzing and recording the tablet discharge caused by printing defects in the device 1G having the above configuration will be described below.

[0292] Fig. 32 is a flow chart showing an outline of the analysis and recording operation of tablet discharge related to a printing defect in the device 1G. Fig. 31 is a plan view explaining the tablet discharge operation related to a printing defect in the device 1G.

[0293] First, the imaging unit 221 acquires a moving image in a plan view of the tablet T placed on the conveyor belt 53 flying at the time when the tablet T with a printing defect passes through the printing defect discharge mechanism 220x (step S41), and outputs the image to the control unit 11E.

[0294] Next, the control unit 11E extracts the center of gravity position of the tablet image from the image for each frame, and calculates a trajectory related to the ejection of the target tablet based on the time-series change in the center of gravity position as shown in Figure 31 (step S42), calculates flight parameters based on the calculated trajectory (step S43), and identifies poor ejection based on the flight parameters (step S44).

[0295] Specifically, as flight parameters, the delay time, which is the time from when the tablet T receives the air blow until it starts flying, and the flight angle shown in FIG. 31 are calculated, and it is determined whether the trajectory related to the discharge crosses the gate passage certification line located inside the groove of the guide plate 223 within a predetermined time, thereby determining whether the discharge operation of the target tablet T is normal. This process can improve the reliability of the print defect discharge operation. Furthermore, even if the gate passage certification line is crossed and the discharge operation of the target tablet T is determined to be normal, early detection of abnormalities is possible by looking at the changes over time in flight parameters such as the delay time and flight angle, such as the difference from the previous or past measurement results.

[0296] If the ejection operation of the target tablet is defective (step S45: Yes), the tablet flight image and flight parameters are saved as log data in the recording medium (step S46), and if the ejection operation is not defective (step S45: No), only the flight parameters are saved as log data in the recording medium (step S47), and the process proceeds to step S48.

[0297] Next, it is determined whether the examination has ended (step S48), and if the examination has not ended (No), the process returns to step S41, and if the examination has ended (Yes), the process ends. This completes the analysis and recording operation of the tablet discharge operation related to the printing defect in the device 1G.

[0298] [Adjustment of print defect sorting unit] In the device 1G, in the operating state related to the circulatory transport shown in the embodiment 1, the adjustment operation of the print defect sorting unit is performed by varying the timing of ejecting air from the air ejection unit 222 to the tablets T placed on and transported on the transport belt 53. By such an operation, the adjustment operation of the print defect sorting unit 220 can be automated. An outline of the adjustment operation of the print defect sorting unit in the apparatus 1G will be described below.

[0299] Fig. 33 is a flow chart showing an outline of the adjustment operation of the print defect sorting unit in the device 1G. First, before performing each operation of Fig. 33, the tablet supply unit 2D, the upstream conveying means 3, and the downstream conveying means 5D are operated to start circulatory conveyance.

[0300] Next, an operation is performed to adjust the setting conditions of the air jetting unit 222, such as the jet pressure, jet timing, or jet time, so that flight parameters such as delay time and flight angle fall within a predetermined range. In this example, the delay time is used as the flight parameter, and an operation to adjust the jet timing is shown as an example.

[0301] First, the ejection timing is set to an initial value less than a reference value (step S50). At this time, the ejection timing of the air ejection unit 220 is set earlier so that the delay time is less than the lower limit.

[0302] Next, operations of steps S41 to S43 are performed. Steps S41 to S43 are the same as the operations in the device 1E shown in Fig. 32, so the same numbers are used and the description will be omitted.

[0303] Next, it is determined whether the delay time is equal to or greater than the lower limit (step S51), and if it is less than the lower limit (No), the ejection timing is gradually delayed (step S52) to lengthen the delay time, and the process returns to step S41; if the ejection timing is equal to or greater than the lower limit (Yes), the process proceeds to step S53.

[0304] In step S53, it is determined whether the delay time exceeds an upper limit value. If the delay time is equal to or less than the upper limit value (No), the ejection timing is gradually delayed (step S54) to increase the delay time, and the process returns to step S41. If the delay time exceeds the upper limit value (Yes), the process proceeds to step S55.

[0305] Next, the ejection timing is set to an optimal value (step S55), and the process ends. The optimal value of the ejection timing may be set to, for example, the average or median of the two set values ​​based on the set values ​​when the determinations in steps S51 and S53 are both Yes. This completes the adjustment operation of the print defect sorting unit in the apparatus 1G.

[0306] <Small summary> As described above, the device 1G of embodiment 7 is equipped with a print defect sorting unit 220 located downstream of the downstream printing unit 4D on the conveying path, which ejects air at defective tablets T whose front and / or back printing quality does not meet a predetermined printing standard, and discharges them from the system through the downstream conveying means 5. The print defect sorting unit 220 acquires a moving image in a plan view of the flying tablets T with print defects, calculates the trajectory of the discharge of the target tablet, and makes it possible to identify discharge defects. If the discharge operation of the target tablet is defective, a tablet flight image is recorded, and if the discharge operation is not defective, flight parameters based on the trajectory of the discharge are recorded.

[0307] In the conventional process of checking for defective printing, the movement of the discharged tablets was only checked by a sensor, and the result of the operation that the tablets were removed was not directly confirmed. In addition, since the result of the defective printing discharge operation was not recorded, it was difficult to clearly identify what phenomenon occurred when a discharge operation failure occurred based on a log, etc. In addition, there was a problem that the deterioration of the air blowing part 222 of the defective printing sorting part 220 and other state changes could not be recognized until the frequency of the trouble increased.

[0308] In contrast, the device 1G according to the seventh embodiment is provided with the above configuration, thereby improving the reliability of the print defect ejection operation. Furthermore, even if the ejection operation does not fail, early detection of equipment abnormalities in the print defect sorting unit 220 is possible by monitoring the change over time in the flight parameters of the ejected tablets. In addition, the circulating transport function can be used to automate the adjustment operation of the print defect sorting unit 220 associated with a change in the type of tablet T, and the efficiency of the work of changing the setting conditions of the device 1G can be greatly improved.

[0309] <Additional Information> The above-described embodiments each show a preferred specific example of the present invention. The numerical values, shapes, materials, components, the arrangement and connection of the components, steps, and the order of steps shown in the embodiments are merely examples and are not intended to limit the present invention. Furthermore, among the components in the embodiments, those that are not described in the independent claims showing the highest concept of the present invention are described as optional components constituting a more preferred embodiment.

[0310] In addition, the order in which the above-mentioned methods are performed is merely for illustrative purposes, and orders other than those described above may be used. In addition, some of the above-mentioned methods may be performed simultaneously (in parallel) with other methods.

[0311] In order to facilitate understanding of the invention, the scale of the components in the drawings may differ from the actual scale. The present invention is not limited to the description of the above embodiments, and may be modified as appropriate without departing from the gist of the present invention.

[0312] Furthermore, at least some of the functions of each of the embodiments and their modified examples may be combined. [Industrial Applicability]

[0313] The tablet printing device and tablet printing method according to one aspect of the present disclosure can be suitably used as a tablet printing device that prints identification information such as characters, figures, and images representing a company name or product name on the front and back of tablets made of various drugs, foods, sweets, etc. in the manufacturing process of pharmaceuticals, etc. In addition, the device can also be used as a printing device that prints information on the front and back of articles such as products, parts, workpieces, packages, and various containers in other manufacturing lines, etc. [Explanation of symbols]

[0314] 1A, 1B, 1C, 1X, 1D, 1E, 1F, 1G Tablet Printing Equipment 1 Base 2, 2D, 2E Tablet supply unit 21 Hopper, 22 Feeder 23 Linear feeder 231 Transport Path 24 Passage detection unit 25 Connecting Lanes 26 Ball Feeder 261 Bowl-shaped rotating member, 262 Spiral blade, 263 Inclined rotating disk 261E Ring-shaped rotating member, 261E Inclined rotating disk 27 Supply Lane 27 28 Abnormal Tablet Rejection Unit 281 imaging unit, 282 air ejection unit 29 Accumulated Tablet Dispensing Guide 291 discharge guide portion, 292 movable peripheral portion 3 Upstream conveying means (upstream linear conveying means 3L) 31, 32 pulley, 33 conveyor belt, 34 detection means 4U Upstream printing section 41U object image capturing unit, 42U print head, 43U inspection image capturing unit 4D downstream printing section 41D object image capturing unit, 42D print head, 43D inspection image capturing unit 14U upstream printing section, 14D downstream printing section 141 object image capturing unit, 142 print head, 143 inspection image capturing unit 144 Linear motion mechanism, 145 Passage detection sensor 5 downstream conveying means (downstream linear conveying means 5L, reversing means 5T, downstream linear conveying means 5LB) 50 movable frame, 51 pulley, 52, 57 Rotating drum (rotating suction conveying means), 53 Conveyor belt 54 presser roller, 55, 59 hollow shaft, 58 intermediate suction means 511, 512 pulley, 513 conveyor belt, 514 pressure pulley 6 Swing Arm 61 Arm member, 62, 63 Bearing 16, 16C Drive mechanism 64, 64C servo motor, 65, 65C reducer, 66 flange 67, 67C Stay, 68 Link mechanism 7 Attitude control mechanism 71, 72, 74 pulley, 73 toothed belt, 75 servo motor 76 Reducer, 77 Stay 8 Good product extraction section 9. Discharge conveying means 91, 92 pulley, 93 conveyor belt 120 Tablet Return Department 121, 122 Tablet Return Mechanism 220 Print Defect Sorting Department 220a, 220b, 220c, 220x Print defect ejection mechanism 221 imaging unit, 222 air ejection unit, 223 guide plate 10. Control Means 11, 11D, 11E control unit, 12, 12D, 12E drive unit T Tablet

Claims

1. A tablet printing device that prints information on the front and back of tablets transported along a transport path, an upstream conveying means for conveying the tablet in a first direction while holding the tablet with one of its front and back surfaces facing downward facing the conveying surface; an upstream printing unit that prints information on the other of the front and back surfaces of the tablet being transported by the upstream transport means, the other surface facing upward; a downstream conveying means having a reversing means located above the upstream conveying means, which holds the tablet conveyed by the upstream conveying means with the other surface facing a conveying surface and reverses the tablet from the first direction to a second direction opposite to the first direction, and a downstream linear conveying means which then conveys the tablet in the second direction; a downstream printing unit that prints information on the one side of the tablet being transported by the downstream transport means, the upstream conveying means and the reversing means are disposed in a boundary region on the conveying path, facing each other with their conveying surfaces spaced apart by a predetermined distance; the reversing means has a suction means having an intake port facing a conveying surface of the upstream conveying means in the boundary area, The suction means sucks the other surface of the tablet on the conveying surface of the upstream conveying means to adsorb and hold the tablet on the conveying surface of the downstream conveying means, thereby transferring the tablet from the upstream conveying means to the downstream conveying means, The predetermined distance is adjustable by changing the position of the downstream transport means and / or the upstream transport means. Tablet printing equipment.

2. the inverting means is a rotary suction and conveying means having a plurality of the suction ports formed on a peripheral surface thereof and configured to be capable of suctioning from the suction ports within a predetermined rotation angle range; The rotary suction conveying means starts suction when the intake port faces a predetermined direction in the boundary region as the rotary suction conveying means rotates, thereby suctioning the other surface of the tablet conveyed by the upstream linear conveying means, suctioning and holding the tablet above the peripheral surface, and conveys the tablet to the downstream linear conveying means while rotating through the predetermined rotation angle range. The tablet printing apparatus according to claim 1.

3. The inverting means includes a first rotary suction and conveying means having a plurality of the suction ports formed on a peripheral surface thereof and configured to be capable of suctioning when the suction ports are in a first rotation angle range; a second rotary suction conveying means disposed above the first rotary suction conveying means, having a plurality of upper air intakes formed on a peripheral surface thereof, and configured to be capable of suctioning when the upper air intakes are in a second rotation angle range; a conveyor belt that is stretched across the first rotary suction conveying means and the second rotary suction conveying means and has a plurality of openings; a swing arm that rotatably supports the first rotary suction and transport means so as to be swingable about a rotation center of the second rotary suction and transport means; an attitude control mechanism that defines a start angle and an end angle of the first rotation angle range; the first rotary suction conveying means starts suction when the intake port faces a predetermined direction in the boundary region as the first rotary suction conveying means rotates, and sucks the other surface of the tablet conveyed by the upstream linear conveying means through the opening of the belt installed on the peripheral surface, thereby suctioning and holding the tablet on the conveying belt while rotating in the first rotation angle range, and conveying the tablet; the conveyor belt conveys the tablet to the second rotary suction conveying means while the tablet is suction-held on the conveyor belt, the first rotary suction conveying means rotates to suck the other surface of the tablet through the opening of the conveying belt installed on the peripheral surface, thereby suctioning and holding the tablet on the conveying belt while rotating through the second rotation angle range, and conveying the tablet to the downstream linear conveying means; the swing arm swings the first rotary suction transport means to change the position of the downstream transport means relative to the upstream transport means; The posture control mechanism compensates for changes in the start point angle and the end point angle of the first rotation angle range caused by the swinging of the first rotary suction and conveyance means, thereby suppressing the changes in the start point angle and the end point angle. The tablet printing apparatus according to claim 1.

4. The posture control mechanism is configured to be able to change a start angle and an end angle of the first rotation angle range by a rotation drive means, and by changing the start angle and the end angle, a predetermined direction in which the intake port faces when the intake port starts suction in the first rotary suction transport means is changed. The tablet printing apparatus according to claim 3.

5. A tablet printing method for printing information on the front and back surfaces of tablets transported along a transport path, comprising: The tablet is held in a state where one of the front and back surfaces of the tablet that faces downward faces a conveying surface, and conveyed upstream in a first direction; Printing information on the other of the front and back surfaces of the tablet being transported upstream, the other surface facing upward; The tablet conveyed upstream is held with the other surface facing the conveying surface, and the tablet is conveyed in such a way that it is inverted from the first direction to a second direction opposite to the first direction, and then conveyed downstream in the second direction; A tablet printing method for printing information on one side of the tablet being transported downstream, the upstream conveyance and the reverse conveyance face each other in a boundary region on the conveyance path with their conveyance surfaces spaced apart by a predetermined distance; In the reverse conveyance, a suction operation is performed from an intake port facing a conveying surface of the upstream conveying means in the boundary area, In the suction operation, the other surface of the tablet on the conveying surface of the upstream conveying means is sucked to adsorb and hold the tablet on the conveying surface of the downstream conveying means, thereby transferring the tablet from the upstream conveying means to the downstream conveying means, The predetermined distance is adjusted by changing the position of the downstream transport means and / or the upstream transport means. Tablet printing method.

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