JP2025001660A - Tablet printer and tablet printing method - Google Patents

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

This disclosure relates to a tablet printing device that prints specific information on the front and back of tablets.

In recent years, tablet printing devices have been used in the manufacturing process of pharmaceuticals, food, confectionery, etc. to print identification information such as letters, figures, and images that represent company names and product names on tablets. These tablet printing devices require the handling of a large number of tablets in order to print information on their front and back surfaces.

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

JP 2017-200495 A

However, in the conventional tablet printing device 1X described in Patent Document 1, as shown in FIG. 35, when the inverted tablet T 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 tablet T may be misaligned on the conveying path, resulting in printing defects in the downstream printing section 6X. Alternatively, the tablet T may be tilted, causing a problem in which the tilted tablet T gets caught in the gap between the rotary suction conveying means 31X and the downstream conveying section 5X.

This disclosure has been made in consideration of the above problems, and aims to provide a tablet printing device and tablet printing method that can suppress positional deviation and tilt of tablets on the conveying path during the tablet transfer process between the upstream conveying section and the downstream conveying section.

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, and includes an upstream transport means that holds the tablet with one of the front and back surfaces of the tablet facing downward facing the 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, a 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 the transport surface and flips the tablet from the first direction to a second direction opposite to the first direction, and a downstream linear transport means that transports the tablet in the second direction, and a downstream printing unit that prints information on the other surface of the tablet that faces upward while the tablet is being transported by the upstream transport means. The tablet is transported by a downstream printing unit that prints information on one side of the tablet, and the upstream transport means and the inverting means are arranged facing each other with their transport surfaces spaced a predetermined distance apart at the boundary area between them on the transport path, and the inverting means has a suction means having an intake port that faces the transport surface of the upstream transport means in the boundary area, and the suction means sucks the other side of the tablet on the transport surface of the upstream transport means to adsorb and hold the tablet on the transport surface of the downstream transport means, thereby transferring the tablet from the upstream transport means to the downstream transport means, and the predetermined distance is adjustable by changing the position of the downstream transport means and/or the upstream transport means.

According to one aspect of the present disclosure, it is possible to provide a tablet printing device and a tablet printing method that can suppress the positional deviation and tilt of tablets on the conveying path during the process of transferring tablets from the upstream conveying section to the downstream conveying section.

1 is a front view showing an outline of the configuration of a tablet printing apparatus 1A according to a first embodiment. FIG. FIG. 1 is a perspective view showing a schematic configuration of a tablet printing apparatus 1A. 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. 2A is a front cross-sectional view of a main portion of the reversing means 5T related to conveyance, and FIG. 2B is a cross-sectional view of the reversing means 5T taken along line A2-A2 in FIG. 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. FIG. 11 is a front view showing an outline of the configuration of a tablet printing apparatus 1B according to a second embodiment. 3A is a front cross-sectional view of a main portion of the reversing means 5TB related to conveyance, and FIG. 3B is a cross-sectional view of the reversing means 5TB taken along line A3-A3 in FIG. 7B is a view of the reversing means 5TB as seen from the arrow B1 in FIG. 7A. FIG. 11 is a front view showing an outline of the configuration of a tablet printing device 1C according to embodiment 3. 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. 10(a) 的图10是变换器5TC的图。 10 (a) is a view of the reversing means 5TC seen from the arrow B2. 10B is a view of the reversing means 5TC taken along the line B3 in FIG. FIG. 11 is a front view showing an outline of the configuration of a tablet printing device 1D according to embodiment 4. 1 is a plan view of a tablet supply section 2D, an upstream printing section 4U, and a discharge conveying means 9 in a tablet printing apparatus 1D. 14 is a cross-sectional view of the tablet printing apparatus 1D taken along line A5-A5 in FIG. 13. FIG. 16 is a flowchart showing an outline of the conveying speed adjustment operation in the tablet printing apparatus 1D. 6A is a plan view showing an outline of the configuration of a tablet supply unit 2E in a tablet printing apparatus 1E of embodiment 5, and FIG. 6B is a cross-sectional view of the tablet supply unit 2E taken along line A6-A6 in FIG. 6A. 13A and 13B are diagrams for explaining an outline of the selective discharge operation of abnormal tablets in the tablet supplying section 2E. 13A and 13B are diagrams for explaining an outline of the discharge operation of accumulated tablets by a first mode of the tablet supplying section 2E. 13A and 13B are diagrams for explaining an overview of the discharge operation of accumulated tablets by the second mode of the tablet supplying section 2E. 13A and 13B are diagrams for explaining an outline of the discharge operation of accumulated tablets by the third aspect of the tablet supplying section 2E. 13 is a flowchart showing an outline of the selective ejection operation of abnormal tablets related to the supply in the tablet printing device 1E. 13 is a flowchart showing an outline of a maintenance operation in the tablet supplying section 2E. 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 device 1E. 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 the operation during normal operation, and (b) is an overview of the operation during maintenance operation. 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 the lines A13-A13 and A14-A14 in FIGS. 25(a) and (b), respectively. 11 is a flowchart showing an outline of a maintenance operation in the tablet printing apparatus 1F. 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. 2 is a front view showing an outline of the configuration of a print defect sorting unit 220. FIG. 29 is a cross-sectional view of the print defect sorting unit 220 taken along line A15-A15 in FIG. 28. 13 is a plan view illustrating the tablet discharge operation due to a printing defect in the tablet printing device 1G. 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. 13 is a flowchart showing an overview of the adjustment operation of the print defect sorting unit in the tablet printing apparatus 1G. FIG. 1 is a front view showing a configuration of a conventional tablet printing device 1X. 1A to 1C are schematic cross-sectional views illustrating the tablet delivery operation from an upstream conveying means to a downstream conveying means in the tablet printing device 1X.

<<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.

This configuration makes it possible to provide a tablet printing device that can suppress 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, it is possible to suppress printing defects in the downstream printing section caused by misalignment of the tablets. Alternatively, it is possible to suppress problems caused by tilted tablets getting caught in the gap between the upstream conveying means and the reversing means caused by tilting of the tablets.

Furthermore, when changing the thickness of the tablet to be printed, the gap between the reversing means and the upstream conveying means can be adjusted to fit the new tablet.

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.

This simple configuration makes it possible to realize a tablet printing device that can suppress 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.

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 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 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.

This configuration allows the gap between the inversion means and the upstream conveying means to be freely adjusted to suit the thickness of the target tablet. In addition, when adjusting the gap, the rotation angle range in which the first rotary suction conveying means can suck through the intake port is maintained, which makes it possible to suppress the misalignment and tilt of the tablet on the conveying path during the process of transferring the tablet from the upstream conveying means to the downstream conveying means when printing on tablets of different thicknesses.

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 rotation drive means, and by changing the start angle and end angle, the predetermined direction in which the intake port faces when the intake port starts suction in the first rotary suction transport means may be changed.

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

In addition, 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.

This configuration makes it possible to provide a tablet printing method that can suppress 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.

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 non-defective product extraction unit arranged downstream of the downstream printing unit, a tablet return unit that returns 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. The tablet supplied from the tablet supply unit may 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.

With this configuration, it is possible to automate the operation of adjusting the pitch of tablets 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 the efficiency of the work of changing the setting conditions of the tablet printing device can be greatly improved.

In another aspect, in any of the aspects described above, a tablet printing device that prints information on the front and back of tablets conveyed along a conveying path may be configured to further include an abnormal tablet removal section in addition to a tablet supply section having a ball feeder, which detects whether the tablet to be supplied is a broken piece or whether the tablet has an abnormal shape, and when it is determined that the tablet to be supplied is a broken piece 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 conveying means.

This configuration avoids the inconveniences that would occur if a discharge outlet or discharge passage were provided in the bowl 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 feed lane and frequent stoppages of the tablet printing device.

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 conveyed along a conveying path may be configured to include an abnormal tablet removal section in a tablet supply section having a ball feeder, and when a score line is detected on the top surface of a tablet to be fed, the abnormal tablet removal section supplies the tablet to an upstream conveying means as a score line-detected tablet, and prints information on the front and back in the upstream printing section and downstream printing section, and when a score line is not detected on the top surface of the tablet to be fed, 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.

Furthermore, tablets that have fallen into the center of the bowl-shaped rotating member and have no score line detected are pushed outward by the spiral blades of the bowl feeder and aligned in a single row along the outer edge, and the abnormal tablet removal unit measures whether or not a score line is detected on the top surface again, and if a score line is detected, the tablet is supplied to the upstream conveying means.

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, or a measurement camera or sensor. In addition, 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 issues such as reduced transport accuracy and transport failures that occur due to the complexity of the device configuration, and issues such as increased device costs.

In another aspect, in any of the aspects described above, the upstream printing unit and the downstream printing unit may be provided with a linear motion mechanism that moves the print head backward or forward relative to the base, and a pair of passage 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 face of the print head, the passing detection sensors being configured so that the nozzle face crosses some of the multiple optical paths when the print head moves backward or forward, and the passing height of the nozzle face may be measured by detecting which optical path is blocked.

This configuration makes it possible to detect ink adhering to the nozzle surface of the print head and prompt the removal of the ink, reducing ink adhesion to areas of the tablet other than the top and bottom surfaces 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.

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 onto defective tablets whose print quality on at least one of the front and back sides does not meet a predetermined printing standard, and ejects the tablets from the downstream conveying means to the outside of the system. The print defect sorting unit may be configured to obtain a moving image of a plan view of the flying tablets with print defects, calculate a trajectory of the ejection of the target tablets, and identify ejection defects. If the ejection operation of the target tablets is defective, the tablet flight image is recorded, and if the ejection operation is not defective, flight parameters based on the trajectory of the ejection are recorded.

This configuration can improve the reliability of the defective print ejection operation. Furthermore, even if the ejection operation does not fail, early detection of equipment abnormalities in the defective print sorting section 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 section when changing tablet types, etc., greatly improving the efficiency of changing the settings of the tablet printing device.

First Embodiment
The configuration of the tablet printing apparatus 1A according to the first embodiment will be described with reference to the drawings. Here, in this specification, the X direction, Y direction, and Z direction in each figure 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 may be the "down" direction.

The scale of the components in each drawing is not necessarily the same as the actual one. In order to make it easier to understand, illustrations of covers and the like may be omitted. For example, some components, transport paths, etc. may be illustrated diagrammatically or roughly. In this specification, the symbol "-" used to indicate a numerical range includes the numerical values at both ends. The materials, numerical values, etc. described in this embodiment are merely examples of preferred ones, and are not limited to these. Appropriate changes are possible within the scope of the technical ideas of this disclosure. Combinations of parts of the configurations of other embodiments are possible within the scope of no contradiction.

<Configuration of the tablet printing device 1A>
The configuration of the tablet printing device 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 device 1A (hereinafter, sometimes referred to as "device 1A") according to the first embodiment, and Fig. 2 is a perspective view showing a schematic configuration of the device 1A.

(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 Figures 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 the 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 the 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.

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

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

The tablet shape may be such that the three-dimensional shapes of the front and back surfaces of the tablet are the same, or may be different, such as having a specific shape such as a score line molded on one surface. The thickness of the tablet T may be, for example, 2 mm to 8 mm, but is not limited to this. The shape of the tablet T in plan view may be a circle, ellipse, oval, rectangle, polygon, etc., or may be other shapes such as a star or irregular shape. The tablet T may be composed of multiple different shapes as long as the thickness is approximately constant.

In this specification, the "front surface" or "back surface" of the tablet T supplied to the device 1A may refer to the surface that is seen by the observer when the tablet T having a flat shape is placed arbitrarily and viewed in a plane, and the other surface located behind the front surface may be referred to as the "back surface." Alternatively, when the top and bottom surfaces of the tablet T have different shapes, either surface may be identified as the "front surface" or the "back surface."

[Tablet supply unit 2]
The tablet supply unit 2 is a unit that supplies multiple tablets T to the system. It is arranged on the base 1 and 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 sequentially outputs them to the upstream conveying means 3.

In this example, as shown in FIG. 2, the feeder 22 is made of a disk-shaped member. The feeder 22 rotates around the central axis 22o (arrow R22 in FIG. 2), 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 the 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.

[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 paper surface 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 downstream printing unit 4U described later.

In this embodiment, the upstream conveying means 3 is composed of upstream linear conveying means 3L arranged on the base 1 in a straight line in the first direction D1, and is driven by the control means 10 to convey the 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).

The upstream conveying means 3 includes a pair of pulleys 31 and 32 that constitute a driving pulley and a driven pulley, and a conveying belt 33 suspended between them.

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 that are driven and controlled by a device drive control unit (not shown). In this example, two conveyor belts 33 are suspended in the axial direction, and tablets T can be held and conveyed on the back surface of each of them.

Here, in order to ensure that the tablets T are held on the conveyor belt 33, for example, the conveyor belt 33 may be provided with multiple air intakes (not shown) and a suction device (not shown) that draws air from the air intakes, so that the tablets T placed on the conveyor belt 33 are reliably held and conveyed by suction and adsorption. In this case, the suction force applied to the tablets T by the upstream conveying means 3 is auxiliary, and is much 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.

The conveyor belt 33 may be a belt having the same specifications as the conveyor belt 53 in the downstream conveyor means 5 described below, except for the circumference.

The system also includes a detection means 34 that detects the time when the tablet T passes a predetermined position on the transport path. The detection means 34 may be a reflective or transmissive optical sensor, a laser detector, an image sensor, or a line camera capable of acquiring images of multiple pixels in a line. The detection means 34 detects the time when the tablet T passes and outputs the detection result to the control means 10.

In this example, the device 1A 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 be inclined relative to the horizontal direction to the extent that the tablet can be transported.

[Upstream printing unit 4U]
The upstream printing unit 4U is a printing unit disposed at a predetermined position on the conveying path in the upstream conveying means 3. The upstream printing unit 4U is disposed above the conveying belt 33 between the 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.

The upstream printing unit 4U is disposed on the base 1 and is configured with, in this order 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.

The target image capturing unit 41U is an image capturing means that captures an image of the printing object by capturing an image of the tablet T being transported, and is disposed opposite the transport surface with a predetermined gap therebetween. The target image capturing unit 41U may be a line camera capable of capturing images of a plurality of pixels arranged in a line in a direction perpendicular to the transport direction. The captured image of the printing object is output to the control means 10, and the control means 10 detects the position and passing timing of the tablet T to be printed in a direction perpendicular to the transport direction based on the image. It is possible to measure the angle of the tablet's score line from the image of the printing object captured by the target image capturing unit 41U, and tablet printing by the print head 42U is possible based on the score line angle information.

The print head 42U is a print head that prints non-contact on the top surface of the tablet T being transported, and is arranged opposite the transport surface with a specified gap between them. For the print head 42U, an inkjet type print head having multiple nozzles in a line perpendicular to the transport direction can be used. With this print head 42U, ink is selectively ejected from nozzles corresponding to the passing position of the tablet T in the Y direction in accordance with the passing time of the tablet T, based on the printing data output from the control means 10 based on the image of the printing object, and a specified pattern is printed on the top surface of the tablet T. Non-contact printing is suitable for printing on various medicines and foods from a hygienic standpoint.

The inspection image capturing unit 43U is an image capturing means that captures an image of the printed tablet T by using the printed tablet T as the 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.

[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.

In the device 1A, the downstream conveying means 5 is composed of a reversing means 5T that reverses the conveying direction of the tablet 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 reversing means 5T on the conveying path and linearly conveys the inverted tablet T in the second direction D2 (arrow T3 in Figs. 1 and 2). While the tablet T is being conveyed by this downstream linear conveying means 5L, printing is performed on one side of the tablet T facing upward by the downstream printing unit 4D described later.

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 the "rotary suction conveying means") that rotates with the driving pulleys 51 (arrow R52 in Figures 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.

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

Figure 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 A-A in (a). As shown in the figure, the conveyor belt 53 is, for example, an endless belt reinforced with a cord, 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.

As shown in Figures 3(a) and (c), the back rubber portion 531 of the conveyor belt 53 is removed within a range of width w at 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 portions 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 portion 531 on both sides of the opening 53a. At this time, the dividing line BL may face either up or down. Furthermore, in this state, by performing suction through the opening 53a, 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.

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 that has a plurality of air intakes 52a on its circumferential surface and communicates 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 chamber 52b within a rotation angle range from 6 o'clock to 0 o'clock in the counterclockwise direction based on the rotation center 52o.

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 in the XZ plane, and (b) is a cross-sectional view of the reversing means 5T cut at 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.

The rotating drum 52 has a hollow cylindrical structure in which both ends of the cylindrical portion 522 are sealed by a pair of flange portions 521, 523 and has a negative pressure chamber 52b inside. The flange portions 521, 523 are each rotatably attached to a hollow shaft 55 via a bearing 524. A seal member 525 is inserted between the inner circumference of the flange portion 523 and the outer circumference of the hollow shaft 55 to ensure airtightness of the negative pressure chamber 52b. A conveyor belt 53 is suspended on the circumferential surface of the rotating drum 52, and the rotating drum 52 rotates together with the pulley 51 when it is driven to rotate (arrow R52 in Figures 1 and 2).

The cylindrical portion 522 that constitutes the circumferential surface of the rotating drum 52 has multiple air intakes 52a 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.

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 that it can move in parallel in 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.

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

The circumferential surface of the hollow shaft 551, which is inserted into the rotating drum 52, has multiple openings 55a formed therein, and a partition member 554 is provided over a predetermined rotation angle range based on the center of rotation 52o. The partition member 554 is fixed to the circumferential surface of the hollow shaft 551 by fasteners 555. This 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 be made to function as the negative pressure chamber 52b, and suction from the intake port 52a of the rotating drum 52 becomes possible within that rotation angle range.

As a result, the reversing means 5T starts suction when the intake port 52a faces a predetermined direction, such as vertically downward, as it rotates, and thereby sucks in the upper surface of the tablet T being transported by the upstream linear transport means 3L, adsorbing and holding the tablet T on the circumferential surface of the rotating drum 52, and while rotating through a predetermined rotation angle range, adsorbs and holds the tablet T, transporting it until the conveying belt 53 leaves the circumferential surface of the rotating drum 52, and then transferring it to the downstream linear transport means 5L.

In the downstream linear conveying means 5L, the tablets T are conveyed in a linear manner by the conveying belt 53. Here too, in order to ensure that the tablets T are held by 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 draws 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.

In this example, the device 1A 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 be inclined relative to the horizontal direction to an extent that allows tablet transport.

[Downstream printing section 4D]
The downstream printing section 4D is a printing unit disposed at a predetermined position on the conveying path of the downstream linear conveying means 5L. Printing is performed on one of the front and back surfaces of the tablet T, which is arranged above and transported by the downstream transport means 5, that faces upward.

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 capture unit 41D, a print head 42D, and an inspection image capture unit 43D. The configurations of the target image capture unit 41D, print head 42D, and inspection image capture unit 43D in the downstream printing unit 4D are the same as the configurations of the target image capture unit 41U, print head 42U, and inspection image capture unit 43U in the upstream printing unit 4U, respectively, and therefore will not be described.

[Good Product Extraction Unit 8]
The non-defective product extraction unit 8 is a mechanism unit that is disposed after the downstream printing unit 4D on the conveying path and transfers tablets T having 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 of the tablets T on the conveying path of the downstream linear conveying means 5L, thereby causing the tablets T to fall onto the conveying path of the discharge conveying means 9 below and transfer them thereto (arrow T4 in FIGS. 1 and 2).

[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 pulleys and driven pulleys 91, 92, and a conveying belt 93 suspended between them.

The print quality of the front and back of the tablet T is judged by the control means 10 based on the image of the printed object captured by the inspection image capture units 43U and 43D. If the print quality of the front and back of the target tablet T meets a predetermined printing standard, the non-defective product extraction unit 8 ejects air based on the instruction of 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 Figures 1 and 2).

In addition, if at least one of the print quality on the front and back of the target tablet T does not meet the specified printing standard, the control means 10 instructs the non-defective product extraction unit 8 not to 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).

[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 which acquires signals from each unit and issues control signals to these units, and a drive unit 12 which applies current to drive means such as motors and piezoelectric elements in each unit based on the control signals to operate them.

The control unit 11 is realized, for example, as a computer having a general CPU (Central Processing Unit) and 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.

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.

<Operation of Device 1A>
The operation of the device 1A having the above configuration will be described below.
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).

At this time, the upstream printing unit 4U prints information on the other of the front and back sides of the tablet T that faces upward as it is being transported by the upstream transport means 3.

Next, in the device 1A, the downstream conveying means 5 holds the tablet T conveyed by the upstream conveying means 3 with the other surface facing the conveying surface of the conveyor belt 53, and after inverting the tablet T from the first direction D1 to a second direction D2 opposite to the first direction (same, arrow T2), it is conveyed linearly in the second direction D2 (same, arrow T3).

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

When changing the thickness of the tablet T to be printed, the movable frame 50 is moved vertically in parallel (M50) relative to the base 1 by a linear motion mechanism (not shown), adjusting the height of the rotating drum 52 supported on the hollow shaft 55 and adjusting the distance (gap) between the reversing means 5T and the downstream conveying means 5 to fit the new tablet T.

Through the above operations, device 1A can achieve tablet printing operations that print information on the front and back of tablets transported along the transport path.

＜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 opposing 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 enable suction from the air intakes 52a within a predetermined rotation angle range, and the rotating drum 52 starts 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.

As described above, in the conventional tablet printing device 1X, when transferring tablets 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. This creates an issue in that the tablet T is pulled back by the negative pressure from the upstream side in the conveying direction as it falls, which causes the tablet to shift or tilt on the conveying path.

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

In contrast, with the device 1A, in the series of operations described above, 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 the positional deviation and tilt of the tablets T on the conveying path that occurred in the conventional tablet printing device 1X.

Figure 5 is a schematic cross-sectional view explaining the tablet transfer operation from the upstream conveying means 3 to the downstream conveying means 5 in the device 1A. As shown in Figure 5, the upstream conveying means 3 and the inverting means 5T are arranged facing each other with the conveying surfaces of the respective conveying 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 inverting means 5T, and may be, for example, 5 to 20% longer than the thickness of the tablet at its narrowest part.

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

At this time, in the process of starting suction of the tablet T in the boundary region BR and transferring it 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 tablet T. Therefore, by exerting a suction pressure P sufficient against gravity from the intake port 52a, positional deviation and tilt of the tablet T on the conveying path during the transfer process is suppressed.

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

In addition, with device 1A, even if the centrifugal force of the rotating drum increases as the speed increases, the tablets T can be reliably adsorbed and held on the peripheral surface by applying sufficient negative pressure to counter the centrifugal force, allowing for stable high-speed transport.

Furthermore, when changing the thickness of the tablet T to be printed, the movable frame 50 can be moved in parallel in 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.

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

<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 inversion means 5TB in the downstream conveying means 5B, and the other configurations are the same as those of the apparatus 1A shown in FIG. 1. Therefore, hereinafter, the configuration of the inversion 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.

[Configuration of downstream conveying means 5B]
The configuration of the downstream transport means 5B in the apparatus 1B will now be outlined.

The downstream conveying means 5B is located above the upstream conveying means 3 and is composed of an inverting means 5TB that inverts (arrow T2 in FIG. 6) the conveying direction of the tablet T from a first direction D1 (rightward in FIG. 6, arrow T1) to a second direction D2 (leftward in FIG. 6), and a downstream linear conveying means 5LB that is located downstream of the inverting means 5TB on the conveying path and linearly conveys the inverted tablet T in the second direction D2 (arrow T3 in FIG. 6). When the tablet T is being conveyed (arrow T3 in FIG. 6) by the downstream linear conveying means 5L, printing is performed on the upper surface of the tablet T from the downstream printing unit 4D.

As shown in FIG. 6, in device 1B, reversing means 5TB includes a swing arm 6 supported on base 1, a rotating drum 52 supported on swing arm 6, a rotating drum 57 disposed at the rotation center 57o of swing arm 6, an intermediate suction means 58 disposed in the space between rotating drum 52 and rotating drum 57, and a conveyor belt 53.

The specific configuration is as follows.
The downstream conveying means 5B includes a driving pulley 51 arranged 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 arranged 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.

The swing arm 6 is attached to the base 1 so that it can swing (arrow R6) around the center of rotation 57o of the rotating drum 57 by a swing mechanism described below, and the swing allows the rotating drum 52 to move 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 tablet T.

In the example shown in FIG. 6, the rotating drum 52 is configured in the same way as the device 1A, so that the air intake 52a communicates with the negative pressure chamber 52b in a rotation angle range from 6 o'clock to 0 o'clock in the counterclockwise direction based on the center of rotation 52o (hereinafter, sometimes referred to as the "first rotation angle range").

As shown in FIG. 6, the rotating drum 57 also has a suction mechanism that has multiple air intakes 57a on the circumferential surface and communicates with a negative pressure chamber 57b formed inside the rotating drum 57 within a predetermined rotation angle range, allowing suction through the air intakes 57a. In the example shown in FIG. 6, the rotating drum 57 is configured such that the air intakes 57a communicate with the negative pressure chamber 57b within a rotation angle range (hereinafter sometimes referred to as the "second rotation angle range") from about 2 o'clock to about 0 o'clock (slightly toward 11 o'clock) in the counterclockwise direction based on the center of rotation 57o.

The intermediate suction means 58 also has a number of intake ports 58a that communicate with the negative pressure chamber 58b inside the intermediate suction means 58 on the wall surface (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 in the conveyor belt 53.

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 the conveyance, in which the reversing means 5TB is cut at the rotating drums 52 and 57 in the XZ plane, and Fig. 7(b) is a cross-sectional view of the reversing means 5TB cut at 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).

As shown in Figures 7(a) and (b), in the reversing means 5TB, a hollow shaft 59 is fixed to the base 1. The swing arm 6 has its base supported by the hollow shaft 59 and swings around the hollow shaft 59. In addition, a rotating drum 57 is rotatably attached to the hollow shaft 59.

A hollow shaft 55 is rotatably supported at the tip of the swing arm 6, and a 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.

The rotating drum 57 has a hollow cylindrical structure in which both ends of the cylindrical portion 572 are sealed by a pair of flange portions 571, 573 and has a negative pressure chamber 57b inside. The flange portions 571, 573 are each rotatably attached to the hollow shaft 59 via a bearing 574. A seal member 575 is inserted between the inner circumference of the flange portion 573 and the outer circumference of the hollow shaft 59 to ensure airtightness of the negative pressure chamber 57b. A conveyor belt 53 is suspended on the circumferential surface of the rotating drum 57, and the rotating drum 57 rotates (arrow R57 in FIG. 6) when the pulley 51 (see FIG. 6) is driven to rotate.

The cylindrical portion 572 that constitutes the circumferential surface of the rotating drum 57 has multiple air intakes 57a opened in the circumferential direction 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 outside space through the openings 53a in the conveyor belt 53.

The hollow shaft 59 is fixed to the base 1 by a flange 590. A pulley 72 with a toothed belt 73 suspended therearound is attached (fixed) to the hollow shaft 59. The hollow shaft 59 is mainly made of 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 to prevent the rotating drum 57 from falling out, and the open end of the base is connected to a vacuum pipe 593 that communicates with a vacuum exhaust device VP (not shown).

The circumferential surface of the hollow shaft 591, which is inserted into the rotating drum 57, has multiple openings 59a formed therein, and a partition member 594 is provided over a predetermined rotation angle range based on the center of rotation 57o. The partition member 594 is fixed to the circumferential surface of the hollow shaft 591 by fasteners 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.

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 the base, and rotatably holds a hollow shaft 55 via a bearing 62 at the tip. 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 the 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 when the servo motor 64 rotates.

The rotating drum 52 has the same configuration as the device 1A shown in Figures 4(a) and (b), so the same components are given the same numbers and their explanations are omitted.

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.

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

In the posture control mechanism 7, as an example, the driven pulley 71 attached (fixed) to the hollow shaft 55 and the driving 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, which is 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, causing the pulley 71 to rotate and the hollow shaft 55 to rotate.

At this time, the hollow shaft 55 rotates to compensate for the angle change caused by the swing, so the absolute angle of the hollow shaft 55 around the axis centered on 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. In other words, 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.

The attitude control mechanism 7 is a mechanism that determines 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 maintenance mechanism.

The start angle of the first rotation angle range refers to the rotation angle at which suction begins from the air intake 52a as the rotating drum 52 rotates, and the end angle of the first rotation angle range refers to the rotation angle at which suction from the air intake 52a is released as the rotating drum 52 rotates.

Except for the above two points, the hollow shaft 55 has the same configuration as the device 1A shown in Figures 4(a) and (b), so the same components are given the same numbers and their explanations are omitted.

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 inside, which is connected to a vacuum exhaust device VP (not shown). In addition, multiple air intakes 58a are provided on the wall surface in the upper right direction of FIG. 7(a).

The reversing means 5TB having the above configuration starts suction when the intake port 52a faces a predetermined direction, such as vertically downward, as it rotates, and suction is applied to the upper surface of the tablet T conveyed by the upstream linear conveying means 3L to adsorb and hold the tablet T on the circumferential 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 circumferential surface of the rotating drum 52. After that, the intermediate suction means 58 adsorbs and holds the tablet T on the conveying belt 53 and conveys it to the periphery of the rotating drum 57, and further adsorbs and holds the tablet T on the circumferential 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.

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

Also, like device 1A, the first direction D1 and the second direction D2 may be configured to be inclined relative to the horizontal direction to an extent that allows tablet transport.

<Operation of Device 1B>
Like the device 1A, the device 1B 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.

In addition, when changing the thickness of the tablet T to be printed, the servo motor 64 is driven to swing the swing arm 6 around the hollow shaft 59, adjusting the height of the rotating drum 52 supported by the hollow shaft 55, and adjusting the gap δ between the reversing means 5TB and the downstream conveying means 5 to match the thickness of the tablet T.

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

＜Effects＞
As described above, in the device 1B, the inversion means 5TB includes a rotating drum 52 having a plurality of air intakes 52a formed on a 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 conveyor belt 53 is installed on a rotating drum 52 and a rotating drum 57 and has a plurality of openings 53a.
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, as it rotates, it sucks the other side of the tablet T through an opening 53a of a 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.

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;
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.

This configuration allows the height of the rotating drum 52 relative to the upstream conveying means 3 to 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.

At this time, the rotation angle range within which the rotating drum 52 can suck air through the intake port 52a is maintained, which makes it possible to suppress misalignment and tilting 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.

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 port 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 to compensate for changes in the start angle and end angle of the first rotation angle range due to the oscillation of the rotating drum 52, thereby maintaining the rotation angle range in which suction is possible.

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

<Configuration of the tablet printing device 1C>
Hereinafter, the tablet printing apparatus 1C according to the third embodiment will be described in detail with reference to the drawings.
9 is a front view showing an outline of the configuration of the 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 of 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 of the apparatus 1B, and the description will be omitted.

[Configuration of downstream conveying means 5C]
The following will briefly explain the configuration of the downstream transport means 5C in the apparatus 1C.

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

As shown in FIG. 9, in device 1C, the rotating drum 52 is configured so that the intake port 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 and end angles of this rotation angle range are configured to be changeable (52a (after adjustment) in FIG. 9).

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 along 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).

As shown in Figures 10(a) and 10(b), in the reversing means 5TC, as in the device 1B, a hollow shaft 59 is fixed to the base 1. The swing arm 6 has its base 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.

A hollow shaft 55 is rotatably supported at the tip of the swing arm 6, and a 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.

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

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 the stay 67C of the swing arm 6.

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 the arm member 61 is rotatably attached to the hollow shaft 59 via a bearing 63 at the base, and rotatably holds the hollow shaft 55 via a bearing 62 at the tip, just like the device 1B.

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 at both ends to the rotating arm 681 and the arm member 61 by joints 682, 684. This configures the arm member 61 to swung around the hollow shaft 59 by the rotation of the servo motor 64C.

The configuration and function of the rotating drum 52 are the same as those of the device 1B, except that the attitude control mechanism 7 can adjust the start and end angles of the rotation angle range in which suction is possible from the intake port 52a of the rotating drum 52.

The configuration and function of the hollow shaft 55 are the same as those of device 1B.

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

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.

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.

<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.

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

Furthermore, by operating the posture control mechanism 7, the absolute angle of the hollow shaft 55 and the partition member 554 around the axis of rotation 52o can be changed, 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 that matches the characteristics of the tablets T, such as their shape and weight.

The upstream conveying means 3 and the reversing means 5TC are arranged facing each other with their conveying surfaces spaced a predetermined distance apart at 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 air intake 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.

The inventors' investigations have revealed that in order to reliably adsorb and transfer tablets T from the upstream conveying means 3 to the downstream conveying means 5 at a position where the gap δ is minimized, it is preferable that the angle at which suction by the rotating drum 52 starts when the transfer operation begins be offset upstream by a few degrees from the rotation angle at which the intake port 52a faces the 6 o'clock direction.

In contrast, device 1C is configured to operate posture control mechanism 7 to change the rotation angle range in which rotating drum 52 can suck air through intake port 52a. Device 1C can adjust the angle range to match the shape, weight, and other characteristics of tablet T, making it possible to transfer tablet T from upstream conveying means 3 to downstream conveying means 5 at a position where gap δ is minimized.

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, as well as the device conditions such as the conveying speed and suction strength.

＜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 specified direction in which air intake 52a in rotating drum 52 faces when it begins suction is changed.

This configuration allows the height of the rotating drum 52 relative to the upstream conveying means 3 to be changed, and the gap δ between the inversion means 5TC and the upstream conveying means 3 to be freely adjusted to suit the thickness of the target tablets T. It also changes the rotation angle range in which the rotating drum 52 can suck air through the intake port 52a, allowing the device to be set to the optimal angle range to suit the characteristics of the tablets T.

This makes it possible to suppress 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 5C when printing on tablets T of different thicknesses.

In addition, with the device 1C, it is possible to adsorb the tablet T under optimal conditions, for example, when the tablet T tends to be transported in an inclined state, such as when one of the front and rear ends is lowered and the other is raised along the transport direction.

<<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.

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

As a variation 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 reduction gear 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 its shape and weight.

Fourth Embodiment
The devices 1A, 1B, and 1C according to the above-mentioned embodiments 1 to 3 are equipped with a tablet supply unit 2, an upstream conveying means 3, an upstream printing unit 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 by transporting the tablets T supplied from the tablet supply unit 2 along a path consisting of the upstream conveying means 3 and the downstream conveying means 5, 5B, and 5C.

In contrast, 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. Device 1D makes it possible to efficiently change the settings of the device when changing the type of tablets T, etc.

<Configuration of the tablet printing device 1D>
Hereinafter, a device 1D according to the fourth embodiment will be described in detail with reference to the drawings.
Figure 13 is a front view showing an outline of the 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.

(Overall composition)
As shown in Figures 13 to 15, the device 1D is equipped with a base 1 that supports each part, has an interior space 1a of the device on the rear side, and functions as a front panel of the housing, a tablet supply unit 2D that supplies tablets T, an upstream conveying means 3 that conveys the supplied tablets, an upstream printing unit 4U that prints information on the tablets T conveyed 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 conveyed 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 conveyed tablets T to the tablet supply unit 2D, a print defect sorting unit 220 that sorts out tablets T related to print defects and removes them from the system, and a control means 10D that controls these elements.

(Outline of each department)
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 mainly be described.

[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 line 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.

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) onto the base end 23a of the linear feeder 23 located below.

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 ball feeder 26. In this example, the linear feeder 23 is arranged so that the two linear feeders 23 extend in different directions, with 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 distributed approximately evenly among the plurality of conveying paths 231 and conveyed in a straight line (arrow T23 in Figures 14 and 15).

The passing detection unit 24 is a tablet passing detection means that is disposed at the end 23b of each linear feeder 23 and 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 a passing sensor (not shown), for example an optical sensor, disposed at each opening 24a. The passing 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.

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 Figures 13 and 14).

The ball feeder 26 is a mechanism unit that rearranges tablets T in a line and outputs them. As shown in Figs. 14 and 15, the ball feeder 26 has a cone-shaped rotating member 261 that rotates around the 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 ball feeder 26, the cone-shaped rotating member 261 rotates around the central axis 26o (arrow R26 in Fig. 14), and the multiple tablets T filled inside the cone-shaped rotating member 261 are pushed outward radially from 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. The tablets T are then sequentially supplied to the supply lane 27 connected to a predetermined position on the outer periphery 261a.

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

[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 the downstream linear conveying means 5LB, printing is performed on one side of the tablet T facing upward by the downstream printing unit 4D. This configuration is the same as the downstream conveying means 5B according to the second embodiment.

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

Specifically, the downstream linear conveying means 5LD includes a pulley 511 arranged facing 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 between them. The pulleys 511 and 512 form a pair of a driving pulley and a driven pulley. Furthermore, a pressure pulley 514 may be provided to determine the position of the conveying belt 33 relative to the conveying belt 513.

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

[Tablet Return Unit 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 transfers the tablets T that have been transported on the transport path of the downstream linear transport means 5LD and passed through the pulley 511 by dropping them into the bowl feeder 26 below via an inclined passage (not shown) (arrow T81 in FIG. 13).

Alternatively, the tablet return unit 120 may be, for example, a tablet return mechanism 122 that is disposed on the 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 fall and be transferred to the hopper 21 below (arrow T82 in FIG. 13).

[Print Defect Sorting Unit 220]
The print defect sorting unit 220 is a mechanism unit that is arranged 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. If 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, based on the instruction of the control means 10D, ejects air blow, for example from the side, against the tablets T on the conveying path of the downstream linear conveying means 5LB, thereby dropping the tablets T downward and discharging them out of the system (arrow T5 in FIG. 13).

[Control Means 10D]
The control means 10D is a circuit that is electrically connected to the tablet supplying unit 2D, the upstream conveying means 3, the upstream printing unit 4U, the downstream conveying means 5D, the downstream printing unit 4D, the non-defective product extracting unit 8, the discharge conveying means 9, the tablet return unit 120, and the 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.

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

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.

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.

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

(3) The printing defect sorting unit 220 sorts tablets T and discharges them outside the system, thereby adjusting the total number of tablets T circulating within the device 1D via the upstream conveying means 3 and the downstream conveying means 5D.

This function allows the device 1D to automate the adjustment of the device's setting conditions when, for example, the type of tablet T is changed.

<Operation of Device 1D>
The operation of the device 1D having the above configuration will be described below.
The device 1D performs a tablet printing operation in which information is printed 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.

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 that have been 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.

The following provides an overview of the conveying speed adjustment operation in device 1D. Figure 16 is a flowchart showing an overview of the conveying speed adjustment operation in device 1D.

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 maximum allowable 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 below. Note that the supply number and the maximum return number may be set to equivalent values.

Next, based on the tablet T passage detection signal output from the detection means 34 arranged at a predetermined position on the conveying path, the pitch data between successive tablets T on the conveying path is calculated (step S13).

Here, the pitch data is the ratio of the pitch of consecutive tablets T to the average length of the tablets T in the conveying direction, and the average length may be, for example, the diameter when the shape of the 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 circular. In addition, the pitch data calculated in step S13 may be the average or minimum value of multiple pitch data calculated from the passing times of consecutive tablets T on the conveying path within a specified time. The reference value of the pitch data may be, for example, 1.7 to 2.3 with respect to the above-mentioned average length in the conveying direction of the 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.

Next, it is determined whether the pitch data is equal to or less than the upper limit (step S14), and if it is greater than the upper limit (No), the number of supplies and the maximum number of returns 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 equal to or less than the upper limit (Yes), the process proceeds to step S16.

In step S16, it is determined whether the pitch data is less than the lower limit. If the pitch data is equal to or greater than the lower limit (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 (Yes), the process proceeds to step S18.

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 determinations in steps S14 and S16 are both Yes.
This completes the adjustment of the transport speed in the apparatus 1D.

<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 unit 2D that supplies tablets T, an upstream transporting means 3 that transports the supplied tablets, an upstream printing unit 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 unit 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 selects 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.

Conventionally, adjustments to the settings of a tablet printing device when changing tablet types, etc., have been performed by the operator manually repeating one-way transport under different settings, for example by receiving tablets that have been transported through the device in a container or the like and manually returning them to the tablet supply unit, then changing the settings and transporting the tablets. This has resulted in issues such as the time it takes to perform the setting and adjustment work, and the need to rely on the experience and intuition of the operator while observing the balance between the tablet supply unit, the upstream transport means, and the downstream transport means.

In contrast, as described above, the tablet printing device 1D according to embodiment 4 has the function of circulating and transporting tablets T along a route including the upstream transport means 3 and downstream transport means 5D, and the function of controlling the maximum supply and return numbers, making it possible to automate the operation of increasing or decreasing the total number of tablets T on the route and adjusting the pitch of tablets T on the transport route to an optimal value. As a result, it is possible to automate the adjustment of the setting conditions of the device 1D in response to changes in the type of tablets T, etc., and to greatly improve the efficiency of the work of changing the setting conditions of the device.

Fifth embodiment
Hereinafter, a tablet printing apparatus 1E (hereinafter, may be referred to as "apparatus 1E") according to embodiment 5 will be described.

<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.

In contrast, device 1E according to embodiment 5 differs from device 1D according to embodiment 4 in that it is configured to detect tablets with broken pieces or abnormal shapes using a tablet supply unit and control means, and prevent abnormal tablets from being supplied to the upstream conveying means 3; the other configurations are the same as device 1D shown in FIG. 13. Therefore, the following mainly outlines the configuration of the tablet supply unit in device 1E and the control means that controls it, and omits a description of the other configurations.

<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 unit 2E and the control means 10E in the device 1E, and (b) is a cross-sectional view of the tablet supplying unit 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 unit 2E.

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, linear feeder 23, passing detection unit 24, and connection lane 25 (part of which is shown in FIG. 17(a)), which are not shown in FIG. 17(a) and (b), and a ball feeder 26, supply lane 27, abnormal tablet removal unit 28, and accumulated tablet dispensing guide 29, which are shown in FIG. 17(a) and (b). Of these elements, in the device 1E, the hopper 21, linear feeder 23, passing detection unit 24, connection lane 25, ball feeder 26, and supply lane 27 have the same configuration as the tablet supply unit 2D shown in FIG. 13 to 15. Therefore, these components are given the same numbers as those in the tablet supply unit 2D and their explanations are omitted. Below, we will mainly explain the configuration of the abnormal tablet removal unit 28 and the accumulated tablet dispensing guide 29 in the tablet supply unit 2E.

In addition to the same configuration and functions as the control means 10D of the device 1D, the control means 10E is configured with 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 following describes the configuration related to the selective removal function of abnormal tablets to be fed in the control means 10E.

[Abnormal tablet removal unit 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 17(b), the abnormal tablet removal unit 28 is composed of an imaging unit 281 and an air ejection unit 282.

The imaging unit 281 is an image acquisition means arranged opposite 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 tablet to be fed is a broken piece or whether the tablet has an abnormal shape based on the shape of the detected contour.

The air ejection unit 282 is disposed outside the outer periphery 261a of the cone-shaped rotating member 261 of the bowl feeder 26, and is a mechanism unit that ejects an air blow toward the inner diameter of the cone-shaped rotating member 261. When the control unit 11E determines that the tablet to be fed is a chip or has an abnormal shape, as shown in FIG. 18(b), the air ejection unit 282 ejects an air blow 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, 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.

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

[Accumulated tablet dispensing guide 29]
The accumulated tablet dispensing guide 29 is arranged on the outer peripheral edge 261a of the funnel-shaped rotating member 261 of the ball feeder 26, and is a radially movable guide mechanism that dispenses abnormal tablets accumulated in the ball feeder 26 when the tip portion 29a close to the center 26o of the ball feeder 26 enters the outer peripheral flat area 261b, and discharges them radially outward from the ball feeder 26, for example during regular maintenance of the device 1E.

As shown in FIG. 17, the accumulated tablet dispensing guide 29 has a discharge guide portion 291 and a movable peripheral portion 292 that extends radially inward of the discharge guide portion 291.

The discharge guide portion 291 is inclined away from the outer peripheral edge 261a of the bowl feeder 26 along the conveying direction of the tablet T.

When the accumulated tablet dispensing guide 29 is positioned radially outward, the movable peripheral portion 292 is positioned on an arc on the outer peripheral edge 261a of the ball feeder 26. In addition, the outer peripheral edge 261a of the ball feeder 26 has a hole or notch 261c 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 positioned at the outermost radial position, and functions as the outer peripheral edge 261a that transports the tablet T along the outer peripheral edge 261a. The discharge guide portion 291 and the movable peripheral portion 292 may be formed integrally.

Figures 19(a) and (b) are diagrams outlining the dispensing operation of accumulated tablets in the first mode of the tablet supply unit 2E, where (a) the upper diagram is a plan view showing the mode during normal operation, (a) the lower diagram is a cross-sectional view taken along line A7-A7 in (a) the upper diagram, (b) the upper diagram is a plan view showing the mode during dispensing operation, and (b) the lower diagram is a cross-sectional view taken along line A8-A8 in (b) the upper diagram.

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

Figures 21(a) and (b) are diagrams outlining the dispensing operation of accumulated tablets by the third mode of the tablet supply unit 2E, where (a) the upper diagram is a plan view showing the mode during normal operation, (a) the lower diagram is a cross-sectional view taken along A11-A11 in (a) the upper diagram, (b) the upper diagram is a plan view showing the mode during dispensing operation, and (b) the lower diagram is a cross-sectional view taken along A12-A12 in (b) the upper diagram. Note that Figures 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 supply unit 2E, with the other omitted.

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 the "dispensing guide 29") is retracted to the position of the outer periphery 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 periphery 261a to the connection position of the supply lane 27 (arrow T27 in FIG. 19(a)). At this time, the movable peripheral portion 292 covers the hole or notch 261c and functions as part of the outer periphery 261a.

On the other hand, when the accumulated tablets are dispensed, as shown in FIG. 19(b), the dispensing guide 29 moves inward radially 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 portion 292 of the dispensing guide 29 moves inward radially, opening the hole or notch 261c. As a result, the tablet T that has been transported 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 through the hole or notch 261c of the outer peripheral edge 261a to the outside of the cone-shaped rotating member 261 (arrow T29 in FIG. 19(b)).

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

In the second mode of the tablet supply unit 2E, unlike the first mode, the dispensing guide 29 is fixed in a state where it has penetrated radially inward 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. Instead, the phase of the spiral blade 262 mounted on the inner inclined surface of the cone-shaped rotating member 261 is configured to be changeable between normal operation and when dispensing accumulated tablets.

Specifically, during normal operation, as shown in FIG. 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 FIG. 20(a)), so the tablet T pushed out radially outward by the spiral blade 262 (arrow T26 in FIG. 20(a)) is transported along the outer periphery 26 to the connection position of the supply lane 27 without coming into contact with the dispensing guide 29 (arrow T27 in FIG. 20(a)).

On the other hand, during the dispense operation of the accumulated tablets, as shown in FIG. 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 FIG. 20(b)), so the tablet T pushed outward radially by the spiral blade 262 (arrow T26 in FIG. 20(b)) is discharged by the dispensing guide 29 to the outside of the cone-shaped rotating member 261 (arrow T29 in FIG. 20(b)).

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 periphery 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.

In the third aspect of the tablet supply unit 2E, instead of the mortar-shaped rotating member 261 of the bowl feeder 26 in the first aspect, a circumferential rotating member 261E is provided that does not have a mortar-shaped portion of the mortar-shaped rotating member 261 and is made of a circumferential flat area near the inside of the outer periphery. Also, instead of the spiral blade 262, an inclined rotating disk 263 is provided in which the 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.

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 part of the outer peripheral edge 261Ea.

On the other hand, when the accumulated tablets are dispensed, as shown in FIG. 21(b), the dispensing guide 29 moves inward radially to a position where it blocks the circumferential rotating member 261E inside the outer periphery 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 inward radially, opening the blocked hole or notch 261Ec. As a result, the tablet T that has been transported inside the circumferential rotating member 261E along the outer periphery 261Ea as the inclined rotating disk 263 rotates is discharged outside the circumferential rotating member 261E by the accumulated tablet dispensing guide 29 (arrow T29 in FIG. 21(b)).

In the plan views of Figures 19(a) and 21(a), the gap between the cumulative tablet dispensing guide 29 and the outer peripheral edge 261a, 261Ea is clearly shown in a schematic manner to distinguish between the holes or notches 261c, 261Ec and the cumulative tablet dispensing guide 29 and the outer peripheral edge 261a, 261Ea, but 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 edge 261a, 261Ea.

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 location of the outer peripheral edge 261a of the ball feeder 26 that overlaps with the movable peripheral portion 292 of the dispensing guide 29.

<Operation of Device 1E>
The operation of the device 1E having the above configuration will be described below.
The operation of the device 1E relating to tablet printing is similar to that of the devices 1A, 1B, and 1C relating to the above-mentioned embodiments 1 to 3, and therefore a description thereof will be omitted.

In addition to tablet printing operations, device 1E also performs operations to detect and selectively remove abnormal tablets for supply. Device 1E also performs operations to dispense abnormal tablets accumulated in bowl feeder 26 during regular maintenance, etc.

[Selective ejection of abnormal tablets]
The selective ejection operation of abnormal tablets in the device 1E will now be described.
FIG. 22 is a flowchart showing an outline of the selective ejection operation of abnormal tablets related to the supply in the tablet printing apparatus 1E.

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

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 periphery 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 the process 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 completed (step S25). If the inspection is not completed (No), the process returns to step S21, and if the inspection is completed (Yes), the process ends.
This completes the selective discharge operation of abnormal tablets in the device 1E.

[Discharge operation of accumulated abnormal tablets]
Next, an outline of the discharge operation of accumulated defective tablets in 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.

First, steady-state operation is performed in which each unit of the device 1E operates to print information on the front and back of the tablet T (step S31), and then it is determined whether a predetermined time has elapsed (step S32). If not (No), the process returns to step S31, and if the 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 periphery 261a of the ball 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.

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

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, and the bowl-shaped rotating member 261 is rotated to discharge the tablets T that have been transferred along the outer periphery 261a along the dispensing guide 29 to the outside of the bowl-shaped rotating member 261.

Next, it is determined whether or not to end the operation (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.

<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.

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

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

In contrast, as described above, the device 1E according to embodiment 5 is configured such that when the control unit 11E determines that the tablet to be fed is a chip or has an abnormal shape, the abnormal tablet removal unit 28 drops the tablet from the circumferential flat area near the inside of the outer periphery 261a of the bowl feeder 26 to the center of the cone-shaped rotating member 261 before it is output to the feed lane 27, thereby preventing the abnormal tablet from being output to the upstream conveying means 3.

This configuration avoids the inconvenience of providing a discharge hole or discharge passage on the outer periphery 261a of the bowl feeder 26, while suppressing the problem of frequent device stoppages caused by blockages in the supply lane 27 due to the inclusion of tablet fragments or tablets with abnormal shapes.

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

In contrast, in a modified version of device 1E, the abnormal tablet removal unit 28 detects the presence 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 information related to the detection, and if no score line is detected on the top surface of the tablet to be supplied, the tablet is removed and returned to the abnormal tablet removal unit 28.

<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.

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

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 top 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 top 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 top surface (Yes), the tablet is fed to the feed lane 27 (step S45), and then determines whether or not score line detection is complete (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.

<Summary>
As described above, the tablet printing device relating to the modified example of device 1E is a tablet printing device that prints information on the front and back of tablets transported along the transport path, and is further equipped with an abnormal tablet removal section 28 in addition to the tablet supply section 2D having a ball feeder 26, and is configured so that, 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, the tablet to be supplied drops into the centre of the ball feeder 26 and is returned to the abnormal tablet removal section 28.

In general, in the field of tablet printing, when printing information 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 printing angle on the front and back sides based on 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.

Therefore, in conventional tablet printing devices, before the printing process on the front and back sides, a measuring device or the like is used to measure the presence or absence of a score line on the front and back sides of the tablet and the angle of the score line, and then the information is printed by aligning the positions of the front and back sides based on the obtained score line angle information.

However, in order to measure the presence and angle of a score line on the front and back of a 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 lines on the front and back is required, which poses issues such as reduced conveying accuracy and prone to conveying failures. In addition, a tablet delivery and conveying mechanism, measurement cameras and sensors, etc. are required for measuring the score lines, which complicates the device configuration of the tablet printing device and increases the device costs.

In contrast, in the modified example of the device 1E according to the fifth embodiment, as described above, when it is determined that the tablet to be fed is 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 mortar-shaped rotating member 261 before it is fed to the feed 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 bowl-shaped rotating member 261 is pushed outward radially by the spiral blade 262 of the bowl feeder 26 and is aligned in a single row along the outer periphery 261a, and the abnormal tablet removal unit 28 again measures 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 feed lane 27.

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 that aligns the angle of the information printing on the front and back sides with the score line on one side can be realized 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, or a measurement camera or sensor. In addition, 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 issues such as a decrease in transport accuracy and a tendency for transport failures to occur due to the complexity of the device configuration, and issues such as increased device costs.

Sixth Embodiment
Hereinafter, a tablet printing apparatus 1F (hereinafter, may be referred to as "apparatus 1F") according to embodiment 6 will be described.

<Configuration of the 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 description will mainly outline the configurations of the upstream printing unit and downstream printing unit in apparatus 1F, and will omit a description of other configurations.

<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 in plan view 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 in maintenance operation, explaining an overview of operation during normal operation. Figures 26(a) and (b) are cross-sectional views showing the 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.

The upstream printing unit 14U is disposed above the conveyor belt 33 between the 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.

The downstream printing unit 14D is disposed above the conveyor 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 conveyed.

Each of the upstream printing unit 14U and 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 capture unit 141, a print head 142, and an inspection image capture unit 143. The configurations of the target image capture unit 141, the print head 142, and the inspection image capture unit 143 are the same as those of the target image capture unit 41U or 41D, the print head 42U or 42D, and the inspection image capture unit 43U or 43D in the device 1D, respectively, and therefore will not be described.

In the device 1F, the print head 142 is an inkjet print head that performs non-contact printing on the top 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 the 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. The print head 142 selectively ejects ink from 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 prints a predetermined pattern on the top surface of the tablet T.

The upstream printing unit 14U and 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 a purging operation is performed to clean the nozzles, or a mechanical cleaning is performed by wiping the nozzle surface 142a with a cleaning blade made of, for example, a rubber material.

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.

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

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

In 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 the print head is cleaned (step S38) in parallel.

Specifically, in the print head cleaning operation (step S38), first, the print head 142 is moved in the Y direction by the linear motion mechanism 144, and is moved 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 are attached to the nozzle surface 142a by detecting which of the multiple optical paths 145a is blocked by the nozzle surface 142a.

Then, after the print head 142 moves to the rear of the base 1, a purge operation is performed to clean the nozzles of the print head 142. In addition, the nozzle surface 142a of the print head 142 may be mechanically cleaned by wiping it with, for example, a cleaning blade.

Next, the linear motion mechanism 144 moves the print head 142 in the Y direction, advancing it 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.

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.

<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.

Conventionally, when ink drips onto the tablet transport path, only ink adhering to the top or bottom surface of the tablet T that can be detected by the inspection image capture unit 143 could be detected, and there was an issue that it was difficult for the defective printing sorting unit to remove tablets with ink adhering to the side.

In contrast, the device 1F according to embodiment 6 is equipped with the above 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.

This configuration can reduce ink adhesion to areas of the tablet T other than the top and bottom surfaces that can be detected by the inspection image capture unit 143, and can suppress the occurrence of defectively printed tablets in which ink adheres to areas other than the top and bottom surfaces of the tablet T, making it difficult for the defective print sorting unit 220 to remove them.

Seventh embodiment
Below, we will explain the tablet printing device 1G (hereinafter sometimes referred to as "device 1G") related to embodiment 7.

<Configuration of the tablet printing device 1G>
The device 1G according to the seventh embodiment is characterized in that it includes 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 the other configurations is omitted.

<Configuration 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 arranged after the downstream printing unit 4D on the conveying path and discharges tablets T related to defective products whose front and back printing quality 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 of the tablet T is judged by the control means 10 based on the printed object image captured by the inspection image capturing units 43U and 43D. If the print quality of the front and back of the target tablet T does not meet the predetermined printing standard, the print defect sorting unit 220 drops the tablet T on the conveying path of the downstream linear conveying means 5L downward and discharges it out of the system based on the instruction of the control means 10 (arrow T5 in FIG. 13).

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

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

The defective print ejection mechanism 220x is composed of an imaging unit 221, an air ejection unit 222, and a guide plate 223.

The imaging unit 221 is an image acquisition means disposed opposite the upper surface of the conveyor belt 53 via a predetermined gap, and acquires a moving image showing a plan view of the tablet T placed on the conveyor belt 53 being discharged. The imaging unit 221 may be, for example, a high-speed camera of 1000 fps using a two-dimensional imaging element. The acquired moving image of the tablet is output to the control unit 11E, which determines whether the discharge operation for the target tablet is normal or not.

The air ejection unit 222 is a mechanism unit that is 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 related to a printing defect based on the images acquired by the inspection image capture units 43U and 43D, as shown in FIG. 31, 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, thereby blowing the tablet off the conveyor belt 53.

The guide plate 223 is a grooved angle-shaped cover member arranged opposite the direction of the air blow, and catches the tablets T blown away by the air blow and drops them downward. In this way, the guide plate 223 ejects tablets T with printing defects from the system.

The print defect ejection mechanisms 220a, 220b, and 220c are configured so 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 capture units 43U and 43D. As a result, the tablets related to the print defect are classified according to the type of print defect and ejected by the guide plates 223 arranged in each of the print defect ejection mechanisms 220a, 220b, and 220c.

The control unit 11E extracts the center of gravity of the tablet image from each frame of the moving image of the tablet, and calculates the trajectory of the ejection of the target tablet T based on the time-series change in the center of gravity of the tablet T, as shown in FIG. 31. Then, by determining whether the trajectory of the ejection is within a predetermined range, it determines whether the ejection operation of the target tablet T is normal.

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

[Analysis and recording operation of tablet discharge related to printing defects]
The following describes the analysis and recording operation of tablet discharge related to printing defects in the device 1G having the above configuration.

Figure 32 is a flowchart outlining the analysis and recording operation of tablet discharge related to printing defects in device 1G. Figure 31 is a plan view explaining the tablet discharge operation related to printing defects in device 1G.

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

Next, the control unit 11E extracts the center of gravity of the tablet image from the image for each frame, and as shown in FIG. 31, calculates the trajectory of the target tablet ejection based on the time-series change in the center of gravity (step S42), calculates flight parameters based on the calculated trajectory (step S43), and identifies ejection failure based on the flight parameters (step S44).

Specifically, as flight parameters, the delay time, which is the time from when the tablet T is blown with air until it starts flying, and the flight angle shown in FIG. 31 are calculated, and it is determined whether the discharge operation for the target tablet T is normal by determining whether the trajectory related to the discharge crosses the gate passage certification line located inside the groove of the guide plate 223 within a specified time. 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 observing 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.

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

Next, it is determined whether or not the examination has ended (step S48). 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 printing defects in the device 1G.

[Adjustment operation of print defect sorting unit]
In the device 1G, in the operating state related to the circulating transport shown in the first embodiment, 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 by 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 device 1G will be described below.

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

Next, the setting conditions of the air ejection unit 222, such as the ejection pressure, ejection timing, or ejection time, are adjusted 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 a flight parameter, and the operation of adjusting the ejection timing is shown as an example.

First, the ejection timing is set to an initial value less than the 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.

Next, steps S41 to S43 are performed. Steps S41 to S43 are the same as those in device 1E shown in FIG. 32, so the same numbers are used and the explanation is omitted.

Next, it is determined whether the delay time is equal to or greater than the lower limit (step S51). 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.

In step S53, it is determined whether the delay time exceeds the upper limit. If the delay time is equal to or less than the upper limit (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 (Yes), the process proceeds to step S55.

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 device 1G.

<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 via 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.

In the conventional process for checking the ejection of defective prints, the movement of the ejected tablets was only checked by a sensor, and the result of the operation to confirm that the tablets had been removed was not directly confirmed. In addition, because the results of the ejection operation of defective prints were not recorded, it was difficult to clearly identify what phenomenon had occurred based on logs, etc., even if an ejection operation malfunction occurred. Another issue was that changes in condition, such as deterioration of the air ejection part 222 of the defective print sorting part 220, could not be recognized until the frequency of the malfunction increased.

In contrast, the device 1G according to embodiment 7 is provided with the above configuration, thereby improving the reliability of the defective printing discharge operation. Furthermore, even if the discharge operation does not fail, early detection of equipment abnormalities in the defective printing sorting unit 220 is possible by monitoring the change over time in the flight parameters of the discharged tablets. In addition, the circulating transport function can be used to automate the adjustment operation of the defective printing sorting unit 220 in response to changes in the type of tablets T, etc., thereby greatly improving the efficiency of the work of changing the setting conditions of the device 1G.

<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.

The order in which the above methods are performed is merely an example to specifically explain the present invention, and orders other than those described above may also be used. Furthermore, some of the above methods may be performed simultaneously (in parallel) with other methods.

In order to facilitate understanding of the invention, the scale of the components in the figures shown in the above embodiments may differ from the actual scale. Furthermore, 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.

Furthermore, at least some of the functions of each embodiment and its modified examples may be combined.

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 letters, figures, and images representing a company name or product name on the front and back of tablets made of various drugs, foods, snacks, etc. in the manufacturing process of pharmaceuticals, etc. It can also be used as a printing device that prints information on the front and back of items such as products, parts, workpieces, packaging, and various containers in other manufacturing lines, etc.

1A, 1B, 1C, 1X, 1D, 1E, 1F, 1G Tablet printing device 1 Base 2, 2D, 2E Tablet supply unit 21 Hopper, 22 Feeder 23 Linear feeder
231 conveying path 24 passing detection unit 25 connecting lane 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 removal section
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 section, 42U print head, 43U inspection image capturing section 4D downstream printing section 41D object image capturing section, 42D print head, 43D inspection image capturing section 14U upstream printing section, 14D downstream printing section 141 object image capturing section, 142 print head, 143 inspection image capturing section 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 (rotary suction conveying means), 53 Conveyor belt 54 Presser roller, 55, 59 Hollow shaft, 58 Intermediate suction means 511, 512 Pulley, 513 Conveyor belt, 514 Presser pulley 6 Swing arm 61 Arm member, 62, 63 Bearing 16, 16C Drive mechanism 64, 64C Servo motor, 65, 65C Speed reducer, 66 Flange 67, 67C Stay, 68 Link mechanism 7 Attitude control mechanism 71, 72, 74 Pulley, 73 Toothed belt, 75 Servo motor 76 Speed reducer, 77 Stay 8 Non-defective product extraction section 9 Discharge conveying means 91, 92 Pulley, 93 Conveyor belt 120 Tablet return section 121, 122 Tablet return mechanism 220 Print defect sorting section 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 Driving unit T Tablet

Claims (5)

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 tablet printing apparatus is configured so that the predetermined distance can be adjusted by changing the position of the downstream conveying means and/or the upstream conveying means. 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 tablet printing device described in claim 1, wherein the rotary suction conveying means starts suction when the air intake port faces a predetermined direction in the boundary area as the tablet rotates, thereby suctioning the other side of the tablet being conveyed by the upstream linear conveying means, 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. 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 tablet printing device according to claim 1, wherein the posture control mechanism compensates for changes in the start angle and end angle of the first rotation angle range that accompany the swinging of the first rotary suction and conveying means, thereby suppressing changes in the start angle and end angle. The tablet printing device described in claim 3, wherein the attitude control mechanism is configured to be able to change the start angle and end angle of the first rotation angle range by a rotation drive 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 starts suction in the first rotary suction conveying means is changed. 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 tablet printing method, further comprising adjusting the predetermined distance by changing the position of the downstream conveying means and/or the upstream conveying means.

Images