JP6810632B2 - Tablet printing device and tablet manufacturing method - Google Patents

Description

The present invention relates to a tablet printing apparatus and a tablet manufacturing method.

Conventionally, the tablet printing apparatus described in Patent Document 1 is known. This tablet printing device sequentially conveys tablets by a conveying belt. Then, characters, marks, and the like are printed on the surface of the transported tablet by an inkjet printer.

An inkjet printer has a nozzle head having a plurality of nozzles. Ink droplets are ejected from a plurality of nozzles of the nozzle head according to a pattern based on print data, thereby printing on tablets.

When such an inkjet printer is used, even if the characters or marks to be printed are changed due to switching of tablet varieties or the like, the print data to be provided can be changed immediately. Further, when an inkjet printer is used, the tablets can be printed without contact. Therefore, it is hygienic and suitable when the tablet to be printed is drinkable.

Japanese Unexamined Patent Publication No. 7-081050

In the above-mentioned printing apparatus, the arrival of the tablet transported by the transport belt is detected by the output of the ON / OFF signal (tablet presence / absence signal) of the sensor provided in the tablet transport path, and printing, inspection, etc. Subsequent processing is being performed. By the way, when there is an interval between adjacent tablets transported by a transport belt, the arrival of each tablet can be detected individually by a sensor, so that each tablet can be printed, etc., and characters and marks can be printed. Can be produced as a printed tablet.

However, for some reason, the tablets may be transported in contact with each other without a gap. In such a case, the sensor cannot recognize the tablets that are transported in contact with each other, particularly the second and subsequent tablets from the beginning. Therefore, it is not possible to normally perform processing such as printing and inspection on these tablets.

An object of the present invention is to provide a tablet printing apparatus and a tablet manufacturing method capable of appropriately processing a tablet even if the tablets are transported without an interval.

In order to achieve the above object, the tablet printing device of the present invention includes a transport device for transporting tablets, a detection unit for detecting fluctuation information of the surface height position of the tablets transported by the transport device, and two. When the above tablets are in contact with each other and transported, a tablet determination unit that identifies each tablet based on the fluctuation information of the height position and a printing unit that prints on the tablet identified by the tablet determination unit. And have.

The printing unit has a defect determination unit that determines whether or not each tablet is defective based on the fluctuation information of the height position of each tablet identified by the tablet determination unit, and the printing unit is determined by the defect determination unit. Tablets determined to be defective may be excluded from printing.

It has an overlap determination unit that determines the overlap of a plurality of tablets based on the fluctuation information of the height position, and the defect determination unit determines whether or not the tablet is defective according to the determination result by the overlap determination unit. You may judge. The overlap determination unit may determine the vertical relationship of the overlapping tablets based on the fluctuation information of the height position.

An inclination determination unit that determines the inclination of the tablet based on the fluctuation information of the height position, and a length determination unit that determines the length of the tablet in the transport direction based on the fluctuation information of the height position. The defect determination unit may determine whether or not the overlapping tablets are defective based on the inclination of the tablet and the length of the tablet in the transport direction.

It may have a discharge device for discharging tablets determined to be defective by the defect determination unit from the transport device, and a collection device for collecting the tablets discharged by the discharge device.

The defect determination unit has an imaging unit that images the tablet identified by the tablet determination unit at least one before and after printing, and the defect determination unit has a defective tablet based on the image data imaged by the imaging unit. It may be determined whether or not.

Further, in the tablet manufacturing method of the present invention, when two or more tablets are in contact with each other and transported by the tablet determination unit, the tablet determination unit is based on the variation information of the tablet height position detected by the detection unit. Each tablet is identified, and the printing unit prints on the tablet identified by the tablet determination unit.

INDUSTRIAL APPLICABILITY According to the present invention, it is possible to provide a tablet printing apparatus and a tablet manufacturing method capable of appropriately processing a tablet even if the tablets are transported without intervals.

It is a figure which shows typically the whole structure of the tablet printing apparatus of 1st Embodiment. It is a figure which shows the state which the tablet placed on the transport belt is seen from the plane direction. It is explanatory drawing which shows the tablet which is conveyed at an interval, and the variation information of the height position thereof. It is explanatory drawing which shows the tablet which is carried in contact with each other, and the variation information of the height position thereof. It is a block diagram which shows the control apparatus in the tablet printing apparatus of 1st Embodiment. It is explanatory drawing which shows the timing when a trigger signal is generated. It is a flowchart which shows the tablet printing procedure. It is explanatory drawing which shows from the detection of a tablet to the image taking. It is explanatory drawing which shows from the image | imaging of the tablet to the printing. It is explanatory drawing which shows the state which a plurality of tablets transported in contact with each other are imaged after the first tablet is detected by a sensor. It is a block diagram which shows the control apparatus in the tablet printing apparatus of 2nd Embodiment. It is explanatory drawing which shows the state which overlap | overlap | occurred the tablet in contact with each other, and the variation information of the height position. It is explanatory drawing which shows the mode in which the tablet overlaps greatly, and the variation information of the height position. It is a block diagram which shows the control apparatus in the tablet printing apparatus of 4th Embodiment. It is explanatory drawing which shows the length and inclination of the overlapping tablet in the transport direction. It is explanatory drawing which shows the mode which provided two sensors. It is explanatory drawing which shows the tablet which is in contact with each other and is shifted in the horizontal direction.

[First Embodiment]
Hereinafter, the first embodiment of the present invention will be described with reference to the drawings.
[Constitution]
[Print object]
The tablet printing apparatus S uses the tablet Tb as a printing object. Tablets Tb include tablets and tablets such as naked tablets (bare tablets), sugar-coated tablets, film-coated tablets (FC tablets), enteric coated tablets, gelatin-encapsulated tablets, multi-layer tablets, and nucleated tablets. The tablet Tb also includes capsule tablets such as hard capsules and soft capsules. The use of such tablets Tb is not limited to pharmaceutical, edible, detergent, industrial and the like. In this embodiment, a tablet having a circular shape in a plan view and an elliptical shape in a side view as shown in FIGS. 2 and 3 will be described as an example.
[Tablet printing device]
The tablet printing apparatus S of the embodiment will be described with reference to FIG. The tablet printing device S includes a supply device 10, a transfer device 20, a sensor 30, a camera 40, a printing unit 50, a discharge device 60, a collection device 70, a storage device 80, and a control device 90.
[Supply device]
The supply device 10 is a device that supplies the tablet Tb to the transfer device 20. The supply device 10 includes a hopper 11, a vibration feeder 12, an alignment feeder 14, and a delivery feeder 16.

The hopper 11 is a container for containing the tablet Tb. The vibration feeder 12 is a transport path for moving the tablet Tb sequentially discharged from the hopper 11 toward the alignment feeder 14. The vibration feeder 12 is provided with a vibrator (not shown). The tablet Tb moves due to the vibration applied to the vibration feeder 12 by this vibrator. The vibration feeder 12 has a vertical path on the hopper 11 side and an inclined path extending to the alignment feeder 14.

The alignment feeder 14 is a device that receives the tablet Tb from the vibration feeder 12 and delivers it to the delivery feeder 16. In the alignment feeder 14, a conveyor belt is wound around two pulleys that are rotated by a drive source (not shown). An alignment guide (not shown) is provided on the transport path of the transport belt. The alignment guide arranges the tablets Tb in two rows, for example, and sequentially conveys the tablets Tb in each row toward the feeder 16.

In the delivery feeder 16, a transport belt having a suction hole is wound around two pulleys (not shown). Inside the conveyor belt, a suction chamber coupled to a suction device (not shown) is provided.

The delivery feeder 16 is arranged above the rear end of the alignment feeder 14 and above the front end of the transfer device 20.

The transport belt of the delivery feeder 16 receives the tablet Tb from the alignment feeder 14 by the suction action of the suction chamber. The transfer belt of the delivery feeder 16 that has received the tablet Tb delivers the tablet Tb to the transfer device 20 at a position where the suction action of the suction chamber does not work. When the tablets Tb are delivered from the supply device 10 to the transfer device 20 in this way, the tablets Tb may be transported on the transfer device 20 in a state where two or more tablets Tb are in contact with each other.
[Transport device]
The transport device 20 is a device for transporting the tablet Tb. The transfer device 20 is arranged on the downstream side of the alignment feeder 14. The transfer device 20 includes a transfer belt 21, a drive pulley 22, a tension pulley 23, two adjusting pulleys 24a and 24b, a suction chamber 25, and an encoder 27. The transport belt 21 is a belt that transports the tablet Tb by adsorbing and holding the tablet Tb and moving the tablet Tb. The transport belt 21 has an endless shape and is wound around a drive pulley 22, a tension pulley 23, and two adjusting pulleys 24a and 24b. In the following description, in the transport device 20, the transport direction due to the movement of the transport belt 21 is indicated by D. Further, the position where the transferred tablet Tb passes first is the upstream side, and the position where the tablet Tb is passed later is the downstream side. The upper side and the lower side of the endless transport belt 21 are opposite to the upstream side and the downstream side.

As shown in FIG. 2, the transport belt 21 is provided with a plurality of through holes 26. The plurality of through holes 26 are formed at predetermined intervals in the moving direction of the transport belt 21. As will be described later, by applying a suction force to the through hole 26, the tablet Tb indicated by the dotted circle in the figure is attracted to the transport belt 21. Further, as described above, depending on the state of being delivered from the supply device 10, as shown in one row of FIG. 2, two or more tablets Tb are in contact with each other, and in this state, they are adsorbed by the transport belt 21 and transported. Ru.

Returning to FIG. 1, the drive pulley 22 is rotated by the motor M. The conveyor belt 21 is driven by the rotation of the drive pulley 22.

The suction chamber 25 has a substantially box shape and is provided inside the annular transport belt 21. In the suction chamber 25, an intake device such as a vacuum pump (not shown) is coupled to an exhaust port 25a formed at a predetermined portion.

With such a suction chamber 25, in the transport belt 21, a through hole 26 located between the drive pulley 22 and the adjustment pulley 24a, a through hole 26 located between the drive pulley 22 and the adjustment pulley 24b, and further drive. A suction force is applied to each of the through holes 26 located on the outer periphery of the pulley 22.

The encoder 27 is a rotary encoder that operates with the rotation of the drive shaft of the motor M. By obtaining the count value of the encoder pulse after the tablet Tb has passed the reference position (reference position), the existing position of the tablet Tb after passing the reference position can be traced. The type of encoder 27 is not specified as long as it can be used to specify the position of the tablet Tb.
[Sensor]
The sensor 30 is a detection unit that detects the height position of the tablet Tb transported to the transport device 20. In FIG. 1, the position for detecting the height position of the tablet Tb transported by the transport belt 21 is the tablet detection position Pd on the transport belt 21 facing the sensor 30. As the sensor 30, for example, a reflection type optical sensor such as a laser sensor can be used. The sensor 30 can detect the distance from the sensor 30 to the detection target. In the present embodiment, the sensor 30 detects the distance from the sensor 30 to the surface of the tablet Tb (the surface opposite to the surface in contact with the transport belt 21, the upper surface in the present embodiment), thereby detecting the tablet Tb. Detects the height position of the surface of. “From the sensor 30” means “from a predetermined reference position” and differs depending on the calculation method of the distance of the sensor. For example, the lower surface of the sensor can be set as a predetermined reference position, but the present invention is not limited to this. The detected value from the sensor 30 is sequentially output to the tablet determination unit 92 described later.

In the present embodiment, the sensor 30 outputs a larger value as the detected distance is shorter. Then, by continuously detecting the height position of the tablet Tb to be transported over time, it is possible to obtain variation information of the height position of the tablet Tb as shown in FIGS. 3 and 4, for example. In the present embodiment, the height position fluctuation information is shown as a waveform indicating the change in the height position. Details will be described later, but by the way, in the waveforms shown in FIGS. 3 and 4, the horizontal axis represents the time axis and the vertical axis represents the output value of the sensor 30.
[camera]
The camera 40 is an imaging unit that images each tablet Tb before printing. The camera 40 takes an image of the tablet Tb conveyed on the upstream side of the printing unit 50, and outputs the image pickup signal to the image processing device 41 (see FIG. 5). The image processing device 41 takes in the image pickup signal from the camera 40 and outputs the posture of the tablet Tb to the defect determination unit 95 (see FIG. 5). The posture of the tablet Tb is a state in which the tablet Tb is displaced, oriented, front and back, etc. on the transport belt 21. Further, the image processing device 41 processes the image pickup signal captured from the camera 40 and outputs the appearance state of the tablet Tb to the defect determination unit 95. The state of appearance is the state of tablet Tb that can be seen from the appearance such as cracking, chipping, foreign matter, and adhesion of dirt. The region on the transport belt 21 that falls within the field of view of the camera 40 includes a predetermined range between the tablet detection position Pd of the transport belt 21 and the print position Pp for printing downstream thereof.

The field of view of the camera 40 may be large enough to capture the entire image of at least one tablet Tb. In addition, in order to ensure that the entire image of one tablet Tb can be captured while suppressing the amount of data of the image to be captured, the entire two tablets Tb can be accommodated at the same time, but the entire three tablets Tb cannot be accommodated. It is conceivable to make it. With such a size, when the image of one tablet Tb is positioned at the center of the visual field range, a part of the images of other tablet Tb adjacent to each other on the upstream side and the downstream side is out of the visual field range. ..
[Printing section]
The printing unit 50 is a mechanism for printing on the tablet Tb transported to the transport device 20. The printing unit 50 includes a printing head 51, a printing confirmation camera 52, and a drying unit 53. In the case of the present embodiment, the print head 51 is the head of an inkjet printer that prints on the surface of the tablet Tb according to the print data. The print head 51 has a plurality of nozzles for printing by ejecting ink droplets by driving an energy generating element such as a piezoelectric element or a heat element. The print head 51 is arranged so as to face the surface of the transport belt 21 at the print position Pp on the downstream side of the camera 40.

The print confirmation camera 52 is an imaging unit that images the tablet Tb after printing. The print confirmation camera 52 takes an image of the tablet Tb after passing through the print head 51, and outputs the image pickup signal to the image processing device 52a. The image processing device 52a takes in the image pickup signal from the camera 52 and outputs the print state to the defect determination unit 95. The field of view of the print confirmation camera 52 is set to a predetermined range on the downstream side of the print position Pp in the transport direction D of the tablet Tb.

The drying unit 53 is provided below the lower portion of the transport belt 21. The drying unit 53 is provided on the drive pulley 22 side of the transport belt 21, and is a device that dries and fixes the ink of characters and marks printed on the surface when the tablet Tb is transported to the transport belt 21.
[Discharge device]
The discharge device 60 is a device that discharges defective tablets Tb from the transport device 20. The discharge device 60 has two air injection nozzles 61 and 62. The blowout side of the air injection nozzles 61 and 62 is provided in the suction chamber 25 at a position facing the collection trays 71 and 72 with the transport belt 21 interposed therebetween. The air injection nozzle 61 of the discharge device 60 injects air and drops the tablet Tb, which is defective due to non-printing, into the collection tray 71 when the tablet Tb reaches a position corresponding to the collection tray 71. When the tablet Tb, which is defective due to poor appearance or poor printing, comes to a position corresponding to the collection tray 72, the air injection nozzle 62 injects air and drops the tablet Tb onto the collection tray 72.
[Recovery device]
The recovery device 70 is a device for recovering defective tablets Tb. The recovery device 70 has recovery trays 71 and 72. The collection trays 71 and 72 are containers that are sequentially arranged on the downstream side of the drying unit 53 and have an open upper side. The collection trays 71 and 72 face the air injection nozzles 61 and 62 with the transport belt 21 interposed therebetween.
[Storage device]
The storage device 80 is a device for storing non-defective tablets Tb. The storage device 80 is a tray that is arranged on the downstream side of the recovery device 70 at a position where the suction action of the suction chamber 25 does not work, and the upper side is open.

The tablets Tb are arranged in two rows by the alignment feeder 14 as described above. It is supplied to the transport belt 21 of the transport device 20 via the delivery feeder 16. In this case, in order to print each of the two rows of tablets Tb on the transport belt 21, the above-mentioned sensor 30, camera 40, print head 51, print confirmation camera 52, drying unit 53, and two airs are actually used. Two sets of the injection nozzles 61 and 62 and the two collection trays 71 and 72 are provided so as to correspond to the two rows of tablets Tb. Since these two sets perform the same operation, one set will be described below.
[Control device]
The control device 90 is a device that controls the operation of the tablet printing device S. The control device 90 can be realized by, for example, a dedicated electronic circuit, a computer operating with a predetermined program, or the like.

The configuration of the control device 90 will be described with reference to FIG. 5, which is a virtual functional block diagram. That is, the control device 90 includes a mechanism control unit 91, a tablet determination unit 92, a defect determination unit 95, a tracking unit 96, a storage unit 97, and an input / output control unit 98.

The mechanism control unit 91 controls a drive source, a valve, a switch, a power supply, and the like of the mechanism unit such as the supply device 10, the transfer device 20, and the printing unit 50. That is, the mechanism control unit 91 controls the transfer speed of the supply device 10 and the transfer device 20, the imaging of the camera 40, the printing by the printing unit 50, the discharge of the defective tablet Tb by the discharge device 60, and the like.

The tablet determination unit 92 identifies each tablet Tb transported by the transport device 20 based on the output signal of the sensor 30, that is, the fluctuation information of the height position of the surface of the tablet Tb. By acquiring the output signal from the sensor 30 in time series as described above, it is possible to obtain the height position fluctuation information, that is, the waveform indicating the height position change as shown in FIG. Identification of the tablet Tb based on such height position fluctuation information is performed, for example, as follows.

First, two threshold values are set in the tablet determination unit 92. As shown in FIG. 3, the first threshold value is the threshold value Hmin for identifying the presence of each tablet Tb, and the second threshold value is the contact and transport of two or more tablets Tb. When so, it is a threshold value Hbrd for identifying the boundary between adjacent tablets Tb. As an example, since the threshold value Hmin is for detecting the change from the state without the tablet Tb to the state with the tablet Tb, the output value of the sensor 30 is set to a low level position. On the other hand, since the threshold value Hbrd detects the boundary between the tablets Tb that are transported in contact with each other, the threshold value is set to a level value lower than the peak value of the output value of the sensor 30 and equal to or higher than the output value from the boundary. Will be done. The low level position described above is a level position less than the output value from the boundary. The two threshold values Hmin and Hbrd may be set to optimum values in advance by experiments or the like.

By the way, as shown in FIG. 3, when the tablets Tb are transported at intervals, the output value of the sensor 30 increases from the time when the tip of the tablet Tb in the transport direction is detected corresponding to each tablet Tb. The peak value is reached in this order beyond the threshold value Hmin and the threshold value Hbrd, and thereafter, the value starts to decrease and becomes the threshold value Hmin or less, and the initial stage when the rear end of the tablet Tb in the transport direction passes through the detection region. Return to level. Therefore, in this case, the output value from the sensor 30 and the threshold value Hbrd intersect at two points, point a and point b, for each tablet Tb.

Further, as shown in FIG. 4, when two tablets Tb are transported in contact with each other, the output value of the sensor 30 increases from the time when the tip of the leading tablet Tb in the transport direction is detected, and the threshold value is increased. The value Hmin and the threshold value Hbrd are exceeded in this order to reach the peak value, and thereafter, the value starts to decrease, and once the boundary portion is approached, once the value falls below the threshold value Hbrd, the value does not drop to the threshold value Hmin. The threshold value Hbrd is exceeded again. After that, after reaching the peak of the output value, it starts to decrease. After that, the transition is the same as the detection of the rear end in the transport direction when the number of tablets Tb is one described above, the threshold value is Hmin or less, and the tablet returns to the initial level. Therefore, in this case, the output value from the sensor 30 and the threshold value Hbrd intersect at four points, point a, point b, point c, and point d. If n (integer) tablets Tb are brought into contact with each other and transported, n × 2 intersections will be obtained.

Therefore, when the intersection of the output value of the sensor 30 that fluctuates with the movement of the tablet Tb and the threshold value Hbrd is detected, the tablet determination unit 92 in the present embodiment sequentially has two tablets (points a and points). b, point c and point d, ...) Are paired, and the position in the transport direction D corresponding to the intermediate position of each pair is recognized (identified) as the center position of each tablet Tb.

Further, identifying each tablet Tb based on the height position variation information also includes recognizing various information about each tablet Tb included in the height position variation information. For example, recognizing the length of each tablet Tb is also included in identifying each tablet Tb. As a more specific example, in the present embodiment, after the points a and b and the points c and d shown in FIGS. 3 and 4 are obtained, between ab and cd. The length on the corresponding transport belt 21 is recognized as a value corresponding to the transport direction length La of the tablet Tb.

When each tablet Tb is identified in this way, the tablet determination unit 92 generates a trigger signal. The trigger signal is a short pulse signal generated at a timing that makes the timing of subsequent processing such as imaging by the camera 40 and the print confirmation camera 52 and printing using the print head 51 appropriate, and is position information of the tablet Tb. Is integrated with. The generation of such a trigger signal will be described with reference to FIG. FIG. 6 (A) schematically shows two or more tablets that are transported at intervals, and FIGS. 6 (B) and 6 (C) schematically show two or more tablets Tb that are transported in contact with each other. There is. For ease of understanding, FIG. 6 shows how the four tablets Tb are transported from right to left in the figure.

For example, as shown in FIG. 6 (A), when the tablets Tb are transported at intervals, the tablet determination unit 92 of the intersection points a and b obtained for each tablet Tb described with reference to FIG. A trigger signal is generated based on the intermediate position.

Further, for example, as shown in FIG. 6 (B), when two or more tablets Tb are in contact with each other and transported, the tablet determination unit 92 has an intermediate position between the intersection points a and b described with reference to FIG. Trigger signals (1), (2), (3), (4) ... are generated in order based on the intermediate position between the intersection points c and d.

In addition, another aspect is introduced here in generating a trigger signal. For example, as shown in FIG. 6C, when two or more tablet Tbs are in contact with each other and transported, the tablet determination unit 92 generates a trigger signal (1) based on the rise of the output signal of the sensor 30. Then, the reference is based on the case where the output signal of the sensor 30 has a waveform indicating a boundary (the point where the output signal of the sensor 30 falls past the peak value of the sensor 30 and starts rising again before crossing the threshold value Hmin). In addition, a trigger signal (2) is generated, and when the tablet Tbs in contact with each other are continuous, a trigger signal (3), (4), ... Is generated each time a waveform indicating a boundary arrives. You may try to do it.

Note that FIG. 6 shows that the trigger signal generation timing is included within the period during which the sensor 30 is detecting the tablet Tb. This is merely an illustration for convenience that the trigger signal is generated using the output signal of the sensor 30. The actual trigger signal is generated at a timing that makes the timing of the subsequent processing appropriate after the detection of the tablet Tb by the sensor 30. That is, it is generated to take timings such as imaging by the camera 40, printing by the print head 51, and imaging by the print confirmation camera 40. Therefore, the trigger signal is generated so that the tablet Tb transported by the transport device 20 reaches the respective processing positions.

For example, the trigger signal is generated at the timing when the tablet Tb reaches the field of view of the camera 40, preferably at the timing when the center of the tablet Tb comes to the center of the field of view of the camera 40. Specifically, as described above, by using the output value of the encoder 27, the existence position of each tablet Tb detected by the sensor 30 after the detection can be traced. Therefore, the timing at which the tablet Tb recognized using the output value of the sensor 30 is positioned in the visual field range of the camera 40, and the center point position of each tablet Tb described with reference to FIGS. 3 and 4 are the positions of the camera 40. The timing of positioning at the center of the field of view can be set by using the output value of the encoder 27.

The camera 40 takes an image based on the trigger signal. Although the image pickup timing by the camera 40 has been described as an example, the print timing by the print head 51 and the image capture timing by the print confirmation camera 40 are also the same. That is, at the timing when it is detected that the tablet Tb recognized by using the output value of the sensor 30 reaches the printing position by the print head 51 and the imaging position by the print confirmation camera 40, respectively, depending on the output value of the encoder 27. Trigger signals are output individually. Then, the print head 51 and the print confirmation camera 40 start processing with reference to their respective trigger signals.

The defect determination unit 95 determines whether or not the tablet Tb is defective. First, the defect determination unit 95 determines whether or not each tablet Tb is defective based on the height position variation information of each tablet Tb identified by the tablet determination unit 92. Here, the height position variation information includes various information such as the length of each tablet Tb as described above. For example, the defect determination unit 95 determines that the tablet Tb is defective if it is shorter than the predetermined length based on whether or not the length of each tablet Tb recognized by the tablet determination unit 92 is equal to or greater than the predetermined length. As a more specific example, when the length between a and b shown in FIG. 3 is 1/2 or less of the transport direction length La of one tablet Tb, it is determined to be defective. The defect determination unit 95 performs a process of preventing the printing unit 50 from printing the tablet Tb determined to be defective. That is, since the printing unit 50 excludes the tablet Tb determined to be defective from the printing target, the tablet Tb that is not printed is generated. In addition, the defect determination unit 95 presets the tablet Tb having a poor appearance with damage such as dirt and chips and the posture state such as misalignment from the processed image captured by the camera 40 and processed by the image processing device 41. Tablets Tb that exceed the above criteria are judged to be defective. Further, the defect determination unit 95 determines that the unprinted tablet Tb and the improperly printed tablet Tb are defective from the processed image captured by the print confirmation camera 52 and processed by the image processing device. To do.

The tracking unit 96 tracks the position of each tablet Tb in the transport device 20. More specifically, the tracking unit 96 identifies the position of each moving tablet Tb from the count value of the encoder pulse by the encoder 27, as described above. For example, in the tracking unit 96, the tablet Tb detected by the sensor 30 reaches the final storage device 80, including the viewing range of the camera 40, the printing by the printing unit 50, and the printing confirmation position of the print confirmation camera 52. Perform tracking. Such tracking by the tracking unit 96 includes tracking the position of the tablet Tb determined to be defective by the defect determination unit 95 in the transport device 20. In particular, the tracking unit 96 distinguishes between the tablet Tb determined to have a poor appearance or a printing defect and the tablet Tb which is not a poor appearance and is not printed.

The storage unit 97 stores various information necessary for processing of the tablet printing apparatus S. The stored information includes the output signal from the sensor 30, the generation timing of the trigger signal, the number of encoder pulses that determine the timing of imaging, printing, etc., the threshold value for identifying the tablet Tb, and the determination of printability. Criteria, criteria such as thresholds for determining defective tablet Tb, image data captured by the camera 40, print data indicating the contents of characters to be printed, marks, etc., position of the tablet Tb to be tracked. Etc. are included.

The input / output control unit 98 is an interface for controlling signal conversion and input / output with each unit to be controlled.

The control device 90 is connected to an output device 99a such as a display, a lamp, and a meter for checking the state of the device. The output signal from the sensor 30, the trigger signal, the image data captured by the camera 40, and the like may be displayed on the output device 99a. Further, the control device 90 is connected to an input device 99b such as a switch, a touch panel, a keyboard, and a mouse for the operator to input information necessary for the operation of the tablet printing device S.
[motion]
The procedure for printing characters and marks on the surface of the tablet Tb in the tablet printing apparatus S of the present embodiment will be described with reference to the flowchart of FIG. 7 and the explanatory views of FIGS. 8 to 10. 8 and 9 show a case where the tablets Tb are transported at intervals, and FIG. 10 shows a case where a plurality of tablets Tb are in contact with each other and transported.

First, as shown in the flowchart of FIG. 7, the supply device 10 supplies the tablet Tb to the transfer device 20 (step S101). That is, the tablet Tb contained in the hopper 11 is passed to the alignment feeder 14 via the vibration feeder 12. The alignment feeder 14 passes, for example, the tablets Tb arranged in two rows to the delivery feeder 16. The delivery feeder 16 delivers the tablet Tb to the transfer device 20. As shown in FIG. 2, the transport device 20 transports the tablets Tb in a state of being sucked and held in two rows on the transport belt 21.

The sensor 30 detects the fluctuation information of the height position of the tablet Tb to be transported. Then, the tablet determination unit 92 recognizes (identifies) the center position in the transport direction D direction for each tablet Tb based on the fluctuation information of the height position, and generates a trigger signal based on the recognized center position. (Step 102). The details of the generation of the trigger signal are as described above. It should be noted that the flowchart of FIG. 7 does not indicate that the processing after step S103 is performed after the trigger signals for all the tablets Tb are generated in step S102. Simultaneously with the generation of the trigger signal for each tablet Tb, processing such as imaging and printing of the preceding tablet Tb is performed. 8 (A) to 8 (C), 10 (A), and (B) show the state of step 102. The defect determination unit 95 determines whether or not the tablet Tb is defective based on the height position fluctuation information, and if it is determined to be defective, the defect determination unit 95 is excluded from the printing target by the printing unit 50.

Returning to the flowchart of FIG. 7, as shown in FIG. 8D, the camera 40 determines the timing at which each tablet Tb should be imaged with reference to the trigger signal (step S103), and images at that timing (step S103). Step S104). For example, as shown in FIG. 8D, an image is taken when the tablet Tb moves and the entire tablet Tb is within the field of view of the camera. As shown in FIGS. 9A to 9C, the subsequent tablet Tb is also detected by the sensor 30 and a trigger signal is generated in the same manner as described above, and imaging is sequentially performed. Further, as shown in FIGS. 10C and 10D, even when two or more tablets Tb are in contact with each other and transported, each tablet Tb is imaged based on the trigger signal in the same manner as described above. ..

The defect determination unit 95 determines whether or not the tablet Tb is defective based on the processed image captured by the camera 40 and processed by the image processing device 41. The determination by the defect determination unit 95 is determined from the length of the transport direction D of each tablet Tb recognized by the tablet determination unit 92, the posture of each tablet Tb detected by the image processing device 41, and the appearance state. (Step S105).

When the defect determination unit 95 does not determine the defect (NO in step S105), the print head 51 prints on the tablet Tb passing through the print position Pp as shown in FIG. 9D (step S106). ..

If the defect determination unit 95 determines that the tablet is defective (YES in step S105), the print head 51 does not print on the tablet Tb that passes through the print position Pp. That is, data that does not print is generated. The unprinted tablet Tb is subject to exclusion (step S110). After that, the tracking unit 96 tracks the position of the unprinted tablet Tb based on the value of the encoder 27.

Further, when the tablet Tb printed at the print position Pp enters the photographing area of the print confirmation camera 52, the print confirmation camera 52 takes an image of a predetermined field of view. The defect determination unit 95 determines whether or not characters and marks are normally printed on the tablet Tb based on the processed image captured by the print confirmation camera 52 and processed by the image processing device (step S107). The tablet Tb determined to have not been printed normally (YES in step S107) is determined to be defective (step S110), and thereafter, the tracking unit 96 tracks the position based on the value of the encoder 27. The tablet Tb determined to be printed normally (NO in step S107) is transported without being determined to be defective.

The tablet Tb that has passed through the field of view of the print confirmation camera 52 is further conveyed as the transport belt 21 moves, and when it is conveyed facing the drying unit 53, the ink of the characters and marks printed on the surface is deposited. It is dried and settled. Further, the tablet Tb heads for the defective product discharge position corresponding to the collection trays 71 and 72 (NO in step S111). As described above, there is a non-defective product discharge position beyond the defective product discharge position. The timing of printing by the print head 51 and imaging of the print confirmation camera 52 is also controlled based on the trigger signal as described above.

When the tablet Tb, which is not defective in appearance but whose position is tracked by the tracking unit 96 without being printed by the determination of the defect determination unit 95 due to the posture or the like, comes to the discharge position corresponding to the collection tray 71 (in step S111). YES), the air injection nozzle 61 injects air. As a result, the tablet Tb is skipped from the transport belt 21 and dropped into the collection tray 71 for collection (step S112).

On the other hand, when the tablet Tb whose position is tracked by the tracking unit 96 as poor appearance and poor printing comes to the discharge position corresponding to the collection tray 72 (YES in step S111), the air injection nozzle 62 injects air. As a result, the tablet Tb is skipped from the transport belt 21 and dropped into the collection tray 72 for collection (step S112).

The normally printed non-defective tablet Tb (NO in step S107) continues to move toward the non-defective discharge position at the transport end (NO in step S108). Then, when the non-defective product discharge position is reached (YES in step S108), the suction action of the suction chamber 25 does not work, and the product falls into the storage device 80 and is accommodated (step S109). That is, it is collected as a good product.
[Action effect]
The tablet printing device S of the present embodiment as described above includes a transport device 20 for transporting the tablet Tb, a sensor 30 for detecting fluctuation information of the height position of the tablet Tb transported by the transport device 20, and two or more. When the tablets Tb are in contact with each other and transported, printing is performed on the tablet determination unit 92 that identifies each tablet Tb and the tablet Tb identified by the tablet determination unit 92 based on the fluctuation information of the height position. It has a part 50 and.

Therefore, even if the tablets Tb are transported without an interval, each tablet Tb can be identified and an appropriate treatment such as printing can be performed on each tablet Tb. As a result, the number of tablets Tb that are not recognized by being in contact with each other and are not printed can be reduced, and the productivity can be improved.

That is, the presence or absence of the tablet Tb is detected by turning the output signal of the sensor 30 ON and OFF, and the output signal of the sensor 30 is changed from OFF to ON for the subsequent imaging by the camera 40 and the printing process by the printing unit 50. When a trigger signal is generated based on the rising edge, if two or more tablets Tb are in contact with each other and conveyed, a rising edge from OFF to ON of the output signal of the sensor 30 occurs only in the leading tablet Tb. Therefore, since the trigger signal is not generated in the subsequent tablet Tb, the tablet printing device S does not recognize that the tablet Tb is supplied to the transport device 20. Therefore, such tablets Tb are not subjected to any processing such as printing. Moreover, such untreated tablets Tb are not excluded. Then, as a result, it is stored in the non-defective product storage device 80, and is mixed with the non-defective product. If there is such a mixture, it becomes necessary to separate the non-defective product and the untreated tablet Tb from the tablet Tb stored in the storage device 80, so that the productivity is lowered.

In the tablet printing apparatus S of the present embodiment, since the tablets are conveyed in contact with each other in this way, the tablets Tb that are not recognized by the tablet printing apparatus S as being supplied can be lost. Therefore, it is not necessary to separate such tablets Tb from non-defective products, and high productivity can be obtained. Further, since it is not necessary to determine the presence or absence of the tablet Tb sequentially by imaging like a moving image, high-speed processing can be performed and high productivity can be obtained. That is, proper treatment can be performed on the tablets Tb transported without any gap.

Further, the present embodiment has a defect determination unit 95 that determines whether or not printing is possible by the printing unit 50 based on the height position fluctuation information of each tablet Tb identified by the tablet determination unit 92, and is a printing unit. Reference numeral 50 denotes a tablet Tb determined to be defective by the defect determination unit 95 to be excluded from the printing target. For example, the tablet determination unit 92 recognizes the length of each tablet Tb from the fluctuation information of the height position, determines whether the defect determination unit 95 is defective or not based on this, and if it is defective, the printing unit 50 prints. Do not do.

As a result, the processing load can be reduced without performing unnecessary printing. It should be noted that it may be determined whether or not the tablet is defective based on the detection time included in the fluctuation information of the height position instead of the length of each tablet Tb. For example, the time when one tablet Tb is detected by the sensor 30 in the transport direction D is obtained from [the length La of the tablet in the transport direction by the transport belt 21] / [the transport speed of the tablet Tb by the transport belt 21]. Therefore, for example, when the time between a and b is 1/2 or less of the time calculated by the above formula, it may be determined to be defective.

Further, the present embodiment includes a discharge device 60 for discharging the tablet Tb determined to be defective by the defect determination unit 95 from the transport device 20, and a collection device 70 for collecting the tablet Tb discharged by the discharge device 60. ..

Therefore, even if the tablets Tb are in contact with each other, the tablets Tb which are judged to be unprintable and are not printed but have no problem as a product are discharged by the discharging device 60 and collected by the collecting device 70. Therefore, it can be re-introduced as a good product and printed.

Further, the present embodiment has an imaging unit that images the tablet Tb identified by the tablet determination unit 92 at least one before and after printing, and the defect determination unit 95 has image data captured by the imaging unit. Based on, it is determined whether or not the tablet Tb is defective.

Therefore, it is possible to more accurately determine whether or not the tablets Tb in contact with each other are defective or not based on the image data.
[Second Embodiment]
This embodiment basically has the same configuration as the first embodiment described above. However, in this embodiment, as shown in FIG. 11, the control device 90 has an overlap determination unit 94. The overlap determination unit 94 determines the overlap of the tablets Tb based on the fluctuation information of the height position of the tablets Tb obtained from the sensor 30. Further, the defect determination unit 95 determines whether or not each tablet Tb is defective according to the determination result by the overlap determination unit 94.

The overlap determination by the overlap determination unit 94 will be described with reference to FIGS. 12 and 13. Note that FIG. 12A shows a case where the tablet Tb1 and the tablet Tb2 are simply in contact with each other without overlapping, as shown in the above embodiment. In FIG. 12B, when a part of the subsequent tablet Tb2 overlaps the preceding tablet Tb1 so as to ride on the subsequent tablet Tb2, FIG. 12C shows that a part of the preceding tablet Tb1 rides on the succeeding tablet Tb2. This is the case when they overlap.

That is, as described in the first embodiment described above, when the two tablets Tb1 and Tb2 are transported in contact with each other as shown in FIG. 12A, the output value of the sensor 30 and the threshold value Hbrd As the intersection of the tablets, the points of the pair of points a and b and points c and d can be sequentially detected for each of the tablets Tb1 and Tb2.

Further, as shown in FIG. 12B, even when the tablet Tb2 is placed on the tablet Tb1 and the tablet Tb2 is overlapped, the points a and b are set as the intersections with the threshold value Hbrd for each tablet Tb. , A pair of points such as point c and point d can be detected. However, the time td1 between a and d when the tablets Tb1 and Tb2 are in contact with each other without overlapping is shorter than the time tdx between a and d when the tablets Tb1 and Tb2 are in contact with each other without overlapping. That is, td1 <tdx. This is because when the tablet Tb2 is overlapped on the tablet Tb1, the end portion of the tablet Tb2 is inside the end portion of the tablet Tb1 when viewed from the plane direction. The overlap determination unit 94 sets tdx as a threshold value in advance, and determines that overlap has occurred when td1 <tdx.

As described above, the overlap determination unit 94 is located between the two points at both ends of the four points obtained based on the threshold value Hbrd used by the tablet determination unit 92 for identifying the tablet Tb and the output value of the sensor 30. When the time of is smaller than the threshold value tdx, it is determined that the overlap has occurred.

This also applies when the tablet Tb1 overlaps with the tablet Tb2 as shown in FIG. 12 (C). That is, even in the case of such an overlap, the time td2 between a and d when the tablets Tb1 and Tb2 are in contact with each other without overlapping is compared with the time tdx between a and d when they are in contact with each other. Becomes shorter. That is, td2 <tdx. Therefore, when td2 <tdx, the overlap determination unit 94 determines that the two tablets Tb1 and Tb2 are overlapped.

Further, the same determination is made when three or more tablets Tb are connected in a row. In this case, as the intersection with the threshold value Hbrd, a pair of points such as points a and b and points c and d can be detected continuously for each tablet Tb. Then, the threshold value tdx is a multiple corresponding to the number of points in the pair, and when the time between the two points at both ends is smaller than the threshold value tdx, it is determined that the overlap occurs.

Further, like the tablet Tb as in the first embodiment, the number of consecutive tablets is calculated based on the waveform in which the output signal of the sensor 30 indicates the boundary, and the calculated number is a multiple of the actual tablet Tb. Comparing the length of the diameter La with the total length of each tablet Tb in a row up to the tablet Tb at both ends, when the length to the tablet Tb at both ends is shorter than a multiple of the length La of the tablet Tb. , It may be determined that the overlap has occurred. In this case, the overlap as shown in FIG. 12 and the overlap as shown in FIG. 13 are mixed, and as the intersection with the threshold value Hbrd, a pair such as a point a and a point b and a point c and a point d for each tablet Tb. Even if the point is not detected, the overlap of the tablets Tb can be determined.

As shown in FIG. 13, when the boundary between the tablet Tb1 and the tablet Tb2 exceeds the threshold value Hbrd due to the large overlap of the tablet Tb2 with respect to the tablet Tb1, two tablets Tb are present. Despite this, the intersection with the threshold value Hbrd becomes two points ab. However, compared to the time tbx between a and b of one tablet Tb1 (or tablet Tb2) when there is no overlap, the time tb between a and b when the tablet Tb1 and the tablet Tb2 overlap significantly. Becomes longer. That is, tb> tbx. Therefore, the overlap determination unit 94 sets tbx as a threshold value in advance, and determines that overlap has occurred when tb> tbx.

The defect determination unit 95 determines that the tablets Tb1 and Tb2 that are determined to overlap by the overlap determination unit 94 are defective. This is because when the tablets Tb overlap, the portion to be printed on the tablets Tb may be obscured, or the posture of the tablets Tb may become slanted and printing may not be performed normally. Similar to the first embodiment, printing is performed on the tablet Tb that is not determined to be defective, and the tablet Tb determined to be defective is not printed, imaged, or the like, and is discharged by the discharge device 60 and sent to the recovery device 70. Will be recovered. For example, it is collected in the collection tray 71 in the same manner as the tablet Tb which is not bad in appearance but is not printed due to the posture or the like.

As described above, the present embodiment has an overlap determination unit 94 that determines the overlap of the tablets Tb based on the height position fluctuation information, and the defect determination unit 95 responds to the determination result by the overlap determination unit 94. It is determined whether or not the tablet Tb is defective. Therefore, even if the tablets Tb are transported in contact with each other, the overlapping tablets Tb can be excluded from the printing target in advance as tablets Tb that are not suitable for printing due to surface hiding, inclination, or the like. .. As a result, it is possible to reduce the processing load of subsequent imaging, defect determination, printing, and the like. In particular, the data capacity can be reduced by saving the number of times of imaging of the imaging unit for performing defect determination.
[Third Embodiment]
This embodiment basically has the same configuration as the second embodiment described above. However, in the present embodiment, the overlap determination unit 94 not only determines the overlap between the tablets Tb, but also determines the vertical relationship of the overlapping tablets Tb, and the defect determination unit 95 determines the defect based on this result. To do.

The determination of the vertical relationship by the overlap determination unit 94 will be described with reference to FIGS. 12 and 14. That is, as shown in FIG. 12 (B), when a part of the tablet Tb2 overlaps the tablet Tb1 so as to ride on the tablet Tb1, the tablet Tb1 is more than the peak value H1 of the output value of the sensor 30 between a and b of the tablet Tb1. The peak value H2 of the output value of the sensor 30 between cd of Tb2 is larger. That is, H1 <H2. Therefore, it is determined that the tablet Tb2 having the larger peak value H2 is on the top. In this way, the overlap determination unit 94 compares the peak values of the waveforms indicating the height positions of the sensors 30 with respect to the tablets Tb1 and Tb2 determined to overlap, and determines the hierarchical relationship.

This is also the case when a part of the tablet Tb1 is overlapped so as to ride on the tablet Tb2 as shown in FIG. 12 (C). That is, in the case of such an overlap, the peak value H1 of the output value of the sensor 30 between a and b of the tablet Tb1 is higher than the peak value H2 of the output value of the sensor 30 between cd of the tablet Tb2. Is also big. That is, H1> H2. Therefore, it is determined that the tablet Tb1 having the larger peak value H1 is on the top.

The same determination is made when three or more tablets Tb are connected in a row. That is, the hierarchical relationship of each tablet Tb can be determined by sequentially comparing the peak value of the output value of the sensor 30 between the intersections of the adjacent tablets Tb with the threshold value Hbrd of each tablet Tb. ..

As described above, the tablet Tb determined to be overlapped with each other and the tablet Tb determined to be on the upper surface are all exposed on the upper surface side which is the printing portion. Therefore, in the present embodiment, at this stage, the defect determination unit 95 does not determine that the tablet Tb determined to be above is defective. However, the defect determination unit 95 determines the defect based on the image captured by the camera 40, and the tablet Tb determined to be defective is not printed as in each of the above-described embodiments, and is regarded as a defect. Be tracked. Tablets Tb that are not determined to be defective are subject to printing. Further, the defect determination unit 95 makes a defect determination based on the image captured by the print confirmation camera 52, and the tablet Tb determined to be defective is tracked as a defect. Subsequent processing is the same as in each of the above-described embodiments.

For the tablet Tb determined to be underneath, a part of the upper surface side, which is the part to be printed, is hidden. Therefore, the defect determination unit 95 determines that the defect is defective and does not print, and then the trigger signal once generated is erased and collected in the collection tray 71.

As described above, in the present embodiment, the overlap determination unit 94 determines the vertical relationship of the overlapping tablets Tb based on the height position variation information. For this reason, the overlapping tablet Tb is not uniformly excluded from the objects to be imaged, printed, etc., but the upper tablet Tb, which is the part to be printed and the upper surface side is entirely exposed, is subject to printing, etc. if it is not defective. Therefore, it is possible to suppress an increase in unprinted tablets Tb.
[Fourth Embodiment]
This embodiment basically has the same configuration as the third embodiment described above. However, as shown in FIG. 14, the present embodiment has an inclination determination unit 94a and a length determination unit 94b. The tilt determination unit 94a determines the inclination of the tablet Tb based on the change information of the height position of the tablet Tb from the sensor 30 for the tablet Tb determined to overlap each other by the overlap determination unit 94. The inclination can be determined by the heights of two points of one tablet Tb detected by the sensor 30 in the transport direction D in time series.

The length determination unit 94b determines the length of the tablet Tb in the transport direction D based on the change information of the height position of the tablet Tb from the sensor 30 for the tablet Tb determined to be overlapped by the overlap determination unit 94. Judge. The length can be determined by the transfer time from the boundary to the boundary of the tablet Tb identified by the tablet determination unit 92 and the transfer speed as described above in the first embodiment.

The length of the tablet Tb referred to here is the length in the transport direction D of the tablet Tb detected by the sensor 30, and differs depending on the position through which the tablet Tb passes and the mode in which the tablet Tb is transported. For example, as shown in FIG. 3, when the tablet Tb is transported at intervals, if the position passing through the center of the tablet Tb is detected, the length of the tablet Tb is almost the actual diameter of the tablet Tb. It becomes La. As shown in FIG. 12 (A), the two tablets Tb are in contact with each other, but when they are transported without overlapping on the top and bottom, it is the same as when they are transported at intervals.

However, when two or more tablets Tb are transported in an overlapping manner, the diameter La of the actual tablet Tb is different from that of the actual tablet Tb. For example, if the tablets Tb are overlapped and tilted or partly hidden, the length of the tablet Tb detected by the sensor 30 becomes shorter than the diameter of the tablet Tb. In FIG. 12B, the length of the lower tablet Tb1 in the case of overlapping is shown by Lu, and the length of the upper tablet Tb2 is shown by Lo. In the example of this figure, both Lu and Lo are shorter than the original diameter La of the tablet Tb.

The defect determination unit 95 determines whether the tablets Tb overlapping each other are defective based on the inclination of the tablet Tb determined by the inclination determination unit 94a and the transport direction length of the tablet Tb determined by the length determination unit 94b. Judge whether or not.

A more specific example of defect determination will be described with reference to FIG. In FIG. 15, among the tablet Tb that overlaps vertically, the lower tablet Tb is referred to as tablet Tb1 and the upper tablet Tb is referred to as tablet Tb2. Further, it is assumed that a threshold value θx indicating the maximum value of the inclination of the tablet Tb that can be printed and a threshold value Lx indicating the minimum value of the length of the tablet Tb that can be printed are set as the threshold value for determining the defect. .. The print head 51 is adjusted so that it can print correctly with a print pattern corresponding to the inclination of the tablet Tb, but if there is an inclination exceeding this adjustable limit, the printed characters, marks, and the like will be displaced. Therefore, a threshold value θx is set as an adjustable limit, and if the slope is equal to or less than this threshold value θx, it can be determined that the product is not defective. The printing pattern is adjusted according to the inclination of the tablet Tb by changing, for example, the ink ejection range, the ejection amount, the ink droplet pitch, and the like on the inclined printing surface of the same tablet Tb. Further, when the tablets Tb are partially hidden due to overlapping, they are excluded from the printing target in the above embodiment, but when the hidden part is very small and the exposed part is large, printing is performed. You may be able to do it. Therefore, a threshold value Lx is set as the printable limit, and if the length is equal to or longer than the threshold value Lx, it can be determined that the product is not defective.

Further, in FIG. 15, as shown in FIG. 12, Lu is the length of the lower tablet Tb1 determined by the length determination unit 94b in the transport direction D, and Lo is the upper side determined by the length determination unit 94b. It is the length of the tablet Tb2 in the transport direction D. d is the length of the overlapping portion in the transport direction D. θ is the inclination of the upper tablet Tb2 determined by the inclination determination unit 94a.

First, as described in the above embodiment, the overlap determination unit 94 determines that the tablets Tb1 and Tb2 that overlap each other have the tablet Tb1 on the lower side and the tablet Tb2 on the upper side. Then, the defect determination unit 95 determines whether or not the lower tablet Tb1 is defective by comparing the length Lu and the threshold value Lx, and the upper tablet Tb2 by comparing the inclination θ and the threshold value θx. To judge.

That is, FIG. 15A shows a case where the length Lu of the lower tablet Tb1 in the transport direction D is the same as the threshold value Lx, and the inclination θ of the upper tablet Tb2 is smaller than the threshold value θx. In this case, since the overlapping portion d of the tablet Tb1 is short and the exposed portion of the surface to be printed is large, the defect determination unit 95 does not determine that the tablet Tb1 is defective. Further, since the inclination of the tablet Tb2 is within the allowable range, the defect determination unit 95 does not determine that the tablet Tb2 is defective.

Next, FIG. 15B shows a case where the length Lu of the lower tablet Tb1 in the transport direction D is shorter than the threshold value Lx and the inclination θ of the upper tablet Tb2 is equal to the threshold value θx. In this case, since the overlapping portion d of the tablet Tb1 is long and the surface to be printed is hidden in a large portion, the defect determination unit 95 determines that the tablet Tb1 is defective. On the other hand, since the inclination of the tablet Tb2 is within the permissible range, the defect determination unit 95 does not determine that it is defective.

Further, FIG. 15C shows a case where the length Lu of the lower tablet Tb1 in the transport direction D is shorter than the threshold value Lx and the inclination θ of the upper tablet Tb2 is larger than the threshold value θx. In this case, since the overlapping portion d of the tablet Tb1 is long and the surface to be printed is hidden in a large portion, the defect determination unit 95 determines that the tablet Tb1 is defective. Further, although the surface of the tablet Tb2 to be printed is not hidden, the inclination is out of the permissible range, so the defect determination unit 95 determines that the tablet Tb2 is defective.

Even if the tablet Tb is determined to be defective by the defect determination unit 95 based on the determination results of the tilt determination unit 94a and the length determination unit 94b, the defect determination unit 94 based on the image obtained by the image taken by the camera 40 is further obtained. If it is determined that the product is not defective as a result of the defect determination by, the product is printed as a non-defective product. The tablet Tb determined to be defective by the defect determination unit 95 is erased from the trigger signal once generated, and is collected in the collection tray 71 as the unprinted tablet Tb.

In this embodiment, the tilt determination unit 94a for determining the inclination of the tablet Tb based on the fluctuation information of the height position of the tablet Tb detected by the sensor 30, and the height position of the tablet Tb detected by the sensor 30. It has a length determination unit 94b for determining the length of the tablet Tb in the transport direction D based on the fluctuation information, and the defect determination unit 95 is based on the inclination of the tablet Tb and the length of the tablet Tb in the transport direction D. Then, it is determined whether or not the tablets Tb overlapping each other are defective.

Therefore, among the overlapping tablets Tb, the tablets Tb that can be printed and the tablets Tb that cannot be printed can be accurately determined, and the tablets Tb that are not printed can be reduced.
[Other Embodiments]
The present invention is not limited to the above embodiments.
(1) The timing of generating the trigger signal of the tablet determination unit 92 is not limited to the above. For example, a trigger signal may be generated immediately after detecting the rise of the output signal of the sensor 30, the boundary or peak of the tablet Tb, and the like. The subsequent processing of the corresponding tablet Tb may be omitted by erasing the once generated trigger signal based on the results of non-printability, defect determination, and the like.

In the above embodiment, when each tablet Tb is identified, the trigger signal is generated by the tablet determination unit 92, and the trigger signal is captured by the camera 40 and the print confirmation camera 52 after the tablet Tb is identified, and the print head. It is said that it is generated at a timing that makes the timing of processing such as printing using 51 appropriate, but it is not limited to this, and the other part of the control device 90 is based on the trigger signal generated by the tablet determination unit 92. May generate a trigger signal for later processing. That is, the trigger signal does not necessarily have to be generated by the same means. Further, the subsequent processing may be performed based on the trigger signal generated when the tablet determination unit 92 identifies the tablet Tb. That is, it is also possible to perform each process at the time from the reference trigger signal to each process, the transfer distance, and the timing of reaching the transfer position, without generating the trigger signal for each process.
(2) The defect determination unit 95 determines whether or not the product is defective, even if it is determined to be defective and the other products are considered to be non-defective products, but the products are determined to be non-defective products and the other products are determined to be defective. It may be. Further, as described above, the defect determination unit 95 determines whether or not the defect is defective when the sensor 30 detects, the camera 40 captures the image, and the print confirmation camera 52 captures the image, but the sensor 30 which is the detection unit determines. Even if it is determined to be defective when the height position fluctuation information is detected, it can be set not to be treated as defective if it can be determined that it is not defective based on the image data by the camera 40 which is the imaging unit. By making a determination in two steps in this way, it is possible to determine whether or not printing is possible more accurately. It is also possible to simplify the process by omitting the defect determination based on the height position fluctuation information by the sensor 30.
(3) The overlap determination by the overlap determination unit 94 may be performed only by comparing the heights of the tablets Tb. That is, as shown in FIGS. 12B and 12C, when the two tablets Tb1 and Tb2 overlap, H1 <H2 or H1> H2. Therefore, when the peak values H1 and H2 of the tablets Tb1 and Tb2 are compared and the two are different, it can be determined that the overlap occurs. As a result, the overlap determination process can be simplified. Further, as described above, the hierarchical relationship between the tablet Tb1 and the tablet Tb2 can be determined by this comparison. The same applies to the third embodiment described above, but in consideration of the fact that the heights of the tablets Tb may differ slightly even if they do not overlap, the comparative determination of the heights of the tablets Tb May provide a width at a value that can be determined to be the same height. That is, when the absolute value of the difference between H1 and H2 exceeds the threshold value, it may be determined that there is a difference in height.
(4) A mode in which the camera 40 is not installed can also be configured. That is, in the above embodiment, the camera 40 takes an image of the tablet Tb for which the trigger signal is generated, and printing or the like is processed based on the captured image. However, the camera 40 is omitted, and the tablet Tb determined to be defective by the defect determination unit 95 is not printed by the printing unit 50, and the tablet Tb determined to be non-defective is printed by the printing unit 50. You may do. Even in this case, the process when two or more tablets Tb are in contact with each other and transported can be performed in the same manner.
(5) In the discharge by the discharge device 60 and the recovery by the recovery device 70, the tablet Tb having a poor appearance, the tablet Tb having a poor print, and the tablet Tb not printed due to a poor posture are determined by the defect determination unit 95 to be unprintable. The unprinted tablets Tb may be discharged separately and collected. That is, a collection tray may be prepared corresponding to each tablet Tb, and the discharge device 60 may discharge when the position corresponding to each collection tray is reached. Moreover, you may collect all these tablets Tb in the same collection tray.
(6) The above embodiment has been described as a tablet printing device S that prints on one side of the tablet Tb. However, the present invention is a tablet printing device S capable of printing on both sides of the tablet Tb by adding a transport device, a sensor, a camera, a printing mechanism, a discharging device, a collecting device, and a storage device having the same configuration as described above. It can also be configured. In this case, at the position where the non-defective product of the transport device 20 is separated, the added transport device, not the storage device 80, receives the non-defective product so that the other side is the printed side. Then, the added sensor, camera, printing mechanism, ejection device, collection device, and storage device perform printing on the other surface, collection of defective products, and storage of non-defective products in the same manner as described above.

Further, the discharging device, the collecting device, and the storing device may be arranged only in the added transport device, and the added transport device may be used to collect defective products, collect unprinted tablet Tb, and store non-defective products. In this case, the tablet Tb supplied to the transfer device 20 is delivered to the added transfer device as it is without being discharged. The result determined by the transfer device 20 is also applied to the printing process of the tablet Tb by the added transfer device.
(7) In the embodiment, in the judgment of the magnitude of the set various values, the judgment of the match / mismatch, etc., it is determined to include the values as above or below, or as greater than, greater than, greater than, less than, less than, less than You are free to set whether to decide not to include the value.
(8) The tablet Tb is supplied on the arrangement line of the through hole 26 of the transport belt 21. Therefore, the sensor 30 is also arranged on the arrangement line of the through holes 26. When the tablets Tb are brought into contact with each other, the contact points are generally on the arrangement line of the through holes 26. That is, the boundary of the tablet Tb is in contact with the sensor 30 and passes through the sensor 30, and depending on the shape of the tablet Tb, the boundary may not be distinguished by the output signal of the sensor 30. Therefore, the sensor 30 may be arranged so as to be offset in the direction orthogonal to the transport direction D from the arrangement line of the through holes 26. In this way, the position detected by the sensor 30 avoids the contact points between the tablets Tb, and it becomes easier to detect the boundary between the tablets Tb.
(9) The number of sensors 30 is not limited to one, and a plurality of sensors 30 may be arranged. For example, as shown in FIG. 16, two sensors 31 and 32 may be arranged in a direction orthogonal to the transport direction D. As shown in FIG. 16, when the flat tablet Tb having few ridges or the like is brought into contact with the tablet Tb, a decrease in the signal output value at the boundary cannot be expected so much. However, by arranging one sensor 31 on the arrangement line of the through hole 26 and the other sensor 32 at a position separated from the arrangement line of the through hole 26, for example, about 1/4 of the diameter of the tablet Tb. At least at the output value from one of the sensors 32, there is a high possibility that the boundary signal will be clear. In this case, two pairs of signals ab from the sensor 31 and a'-b'signals from the sensor 32 are obtained for one tablet Tb at the intersection with the threshold value Hbrd. For this, it is conceivable to find the midpoint of each of the two pairs and take the average value.

Further, as shown in FIG. 17, the arrangement of the plurality of sensors 30 is effective even when the tablet Tb1 overlaps the tablet Tb with a deviation in the horizontal direction instead of the vertical direction. In FIG. 17, the time td3 between a and d is shorter than tdx. However, in this case, since H1 = H2, the overlap determination unit 94 can determine that the top and bottom do not overlap. Further, when such a tablet Tb1 and a tablet Tb2 are laterally offset and overlapped with each other, a sensor 30 is additionally provided in a direction orthogonal to the transport direction D, so that each tablet Tb can be more accurately provided. The state can be grasped, and subsequent defect determination and print pattern adjustment can be facilitated.

Further, the sensors 31 and 32 may be arranged so that the two detection points are on the same line in the transport direction D and the two points of one tablet Tb can be detected at the same time. Thereby, two points of one tablet Tb can be detected, and the inclination of the tablet Tb can be obtained from the difference between the distance between the two places in the transport direction D and the height detected by the two detection units 31 and 32. .. As a result, the inclination can be obtained more accurately.

Further, another sensor may be arranged so that the detection points are aligned with the sensor 31 or the sensor 32 on the same line in the direction orthogonal to the transport direction D. By simultaneously detecting two points of one tablet Tb at the intervals of the detection points arranged in this way, the inclination of the tablet Tb in the direction orthogonal to the transport direction D can be similarly obtained. As a result, the inclination can be obtained more accurately.

In the above embodiment, the fluctuation information of the height position of the upper surface of the tablet Tb was used. However, the fluctuation information of the height position from the transport belt 21 to the upper surface of the tablet Tb may be used. In this case, the distance from the sensor 30 to the transport belt 21 and the distance from the sensor 30 to the upper surface of the tablet Tb are obtained, the fluctuation of the difference between the two is calculated, and the distance is used as the height position. By doing so, the fluctuation of the height position of the surface of the transport belt 21 can be taken into consideration, so that the accuracy of the fluctuation information is improved.

Further, in the embodiment, the sensor 30 uses a reflection type optical sensor such as a laser sensor, but the beam shape of the laser is not limited. For example, it may be a spot beam or a line beam. It can also be applied to an image sensor such as a line sensor. When applying the line sensor, the output signal is turned on when there is an output exceeding the threshold value, instead of processing it as an image. Further, light other than laser may be used, and ultrasonic waves may be used. If the tablet Tb on the transport belt 21 can be detected, various sensors can be applied.
(10) In the embodiment, the state of the tablet Tb such as cracks, chips, and stains is confirmed from the image captured by the camera 40, but the state of the tablet Tb does not necessarily have to be confirmed. Further, the state of the tablet Tb may be confirmed by an imaging unit provided separately from the camera 40. For example, it can be performed by the print confirmation camera 52, or by a camera provided completely separately. When the state of the tablet Tb is confirmed after printing, the condition for determining that the tablet Tb can be printed by the print head 51 does not include the appearance state such as cracks, chips, and stains of the tablet Tb.
(11) In the embodiment, which has been described with the inkjet printer, the printing unit 50 may be able to print on the tablet Tb at various timings in a non-contact manner, and may be, for example, a laser printer.
(12) In the embodiment, the drying unit 53 is provided, but the drying unit 53 does not necessarily have to be provided as long as it can be dried during transportation.
(12) The configuration and delivery method of the supply device 10 are not limited to the above aspects, as long as the tablets Tb can be supplied to the transfer device 20.
(13) Although the embodiment of the present invention and the modification of each part have been described above, the embodiment and the modification of each part are presented as an example, and the scope of the invention is not intended to be limited. .. These novel embodiments described above can be implemented in various other embodiments, and various omissions, replacements, and changes can be made without departing from the gist of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are also included in the invention described in the claims.

10 Supply device 11 Hopper 12 Vibration feeder 14 Alignment feeder 16 Second delivery feeder 20 Transport device 21 Transport belt 22 Drive pulley 23 Tension pulley 24a, 24b Adjustment pulley 25 Suction chamber 26 Through hole 27 Encoder 30 Sensor 40 Camera 50 Printing section 51 Printing Head 52 Print confirmation camera 52a Image processing device 53 Drying unit 60 Discharge device 61, 62 Air injection nozzle 70 Recovery device 71, 72 Recovery tray 80 Storage device 90 Control device 91 Mechanism control unit 92 Tablet judgment unit 94 Overlap judgment unit 94a Tilt judgment Unit 94b Length determination unit 95 Defect determination unit 96 Tracking unit
97 Storage unit 98 Input / output control unit 99a Output device 99b Input device S Tablet printing device Tb Tablet

Claims (10)

A transport device that transports tablets and
A detection unit that detects fluctuation information on the height position of the surface of tablets transported by the transfer device, and
When two or more tablets are in contact with each other and transported, a tablet determination unit that identifies each tablet based on the height position fluctuation information, and a tablet determination unit.
A printing unit that prints on the tablet identified by the tablet determination unit,
A tablet printing apparatus characterized by having. It has a defect determination unit that determines whether or not each tablet is defective based on the fluctuation information of the height position of each tablet identified by the tablet determination unit.
The tablet printing apparatus according to claim 1, wherein the printing unit excludes tablets determined to be defective by the defect determining unit from the printing target. It has an overlap determination unit that determines the overlap of a plurality of tablets based on the fluctuation information of the height position.
The tablet printing apparatus according to claim 2, wherein the defect determination unit determines whether or not the tablet is defective according to the determination result by the overlap determination unit. The tablet printing apparatus according to claim 3, wherein the overlap determination unit determines the vertical relationship of overlapping tablets based on the fluctuation information of the height position. An inclination determination unit that determines the inclination of the tablet based on the fluctuation information of the height position,
A length determination unit that determines the length of the tablet in the transport direction based on the height position fluctuation information, and a length determination unit.
Have,
The defect determination unit according to any one of claims 2 to 4, wherein the defect determination unit determines whether or not the overlapping tablets are defective based on the inclination of the tablet and the length of the tablet in the transport direction. The tablet printing device described. A discharge device that discharges tablets determined to be defective by the defect determination unit from the transport device, and
A collection device that collects the tablets discharged by the discharge device, and
The tablet printing apparatus according to any one of claims 2 to 5, wherein the tablet printing apparatus has. It has an imaging unit that captures images of the tablet identified by the tablet determination unit at least before and after printing.
The tablet printing apparatus according to any one of claims 2 to 6, wherein the defect determination unit determines whether or not the tablet is defective based on the image data captured by the imaging unit. The transport device has a transport belt formed at predetermined intervals in the transport direction of the tablet and having a plurality of through holes for sucking the tablet.
The tablet printing apparatus according to any one of claims 1 to 7, wherein the detection unit has a detection position at a position shifted in a direction orthogonal to the transport direction of the tablet from the arrangement line of the through holes. .. The transport device has a transport belt formed at predetermined intervals in the transport direction of the tablet and having a plurality of through holes for sucking the tablet.
The detection unit according to claim 1 to 7, wherein the detection unit has a detection position on the arrangement line of the through holes and a position shifted from the arrangement line in a direction orthogonal to the transport direction of the tablet. The tablet printing apparatus according to any one. When two or more tablets are brought into contact with each other by the transport device , the tablet determination unit identifies each tablet based on the variation information of the tablet height position detected by the detection unit.
A tablet manufacturing method, wherein the printing unit prints on a tablet identified by the tablet determination unit.

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