JP7515530B2 - Edible object transport state detection device and printing device - Google Patents

Description

The present invention relates to a device for detecting the transport state of edible objects and a printing device.

As an example of a device that detects and prints the transport state of edible objects such as medicines and food, a tablet printing device disclosed in Patent Document 1 is known. This device is configured to capture images of randomly supplied tablets using a line sensor camera to obtain image data, and only when the brightness of the image data is at a certain level or above and this state continues for a certain period of time or more, the device imports the image data as image data for the tablet and performs printing.

Patent No. 5688770

When two adjacent tablets are transported in a state where they are in contact with each other, known as twin tablets, the tablet printing device disclosed in Patent Document 1 may capture these as image data for a single tablet, which may result in printing errors such as misalignment, chipping, or omissions.

The present invention aims to provide an edible body transport state detection device that can easily and reliably detect the transport state of an edible body, and a printing device equipped with the same.

The object of the present invention is achieved by an edible body transport state detection device comprising a transport unit which transports a plurality of edible bodies in a line along a transport path, a detection unit which detects the edible bodies transported by the transport unit, and a control unit which obtains one-dimensional or two-dimensional appearance information of the edible bodies based on detection by the detection unit and determines whether each edible body is transported in a separated state by comparing an index value based on the appearance information with a reference value, wherein the detection unit is a camera and the control unit uses at least one of the area, contour length, fillet diameter, circularity or shape consistency of the edible bodies as the index value .

It is preferable that this edible body transport state detection device further includes a return section that selectively returns edible bodies that have passed the detection section to the upstream side of the detection section in the transport direction, and it is preferable that the control section operates the return section for multiple edible bodies that have been determined to be in an unseparated state, causing them to pass through the detection section again.

The above-mentioned object of the present invention is also achieved by a printing device that includes the above-mentioned edible body transport state detection device and a printing unit that prints on edible bodies that have been determined to be in a separated state.

The edible body transport state detection device of the present invention can easily and reliably detect the transport state of the edible body.

1 is a schematic front view of a printing device according to an embodiment of the present invention. 2 is a cross-sectional view taken along line AA of FIG. 1. FIG. 2 is a plan view showing a main part of the printing device shown in FIG. 1 . 2 is a plan view showing another main part of the printing device shown in FIG. 1 . FIG. 2 is a block diagram of the printing apparatus shown in FIG. 1 . 2 is a diagram for explaining the operation of the printing apparatus shown in FIG. 1 . 10A to 10C are diagrams illustrating the operation of a printing device according to another embodiment of the present invention.

The following describes an embodiment of the present invention with reference to the accompanying drawings. FIG. 1 is a schematic front view of a printing device 1 according to one embodiment of the present invention. As shown in FIG. 1, the printing device 1 includes an edible body transport state detection device (hereinafter simply referred to as the "transport state detection device") 100. The transport state detection device 100 includes a transport unit 2, a detection unit 30, and a return unit 40. The edible body is a small item having a fixed shape, such as a tablet, capsule, empty capsule, solid food, etc. In this embodiment, an example will be described in which the edible body is a tablet.

Figure 2 is a cross-sectional view taken along line A-A in Figure 1, and Figure 3 is a plan view of the main parts of the conveying section 2 shown in Figure 1. As shown in Figures 1 to 3, the conveying section 2 includes a first conveying device 10 and a second conveying device 20. The first conveying device 10 includes a cap-shaped disk 11, an intermediate ring 12 that houses the disk 11, and a rotating ring 13 that houses the intermediate ring 12.

While the rotation axes 11a, 13a of the disk 11 and the rotating ring 13 extend vertically, the rotation axis 12a of the intermediate ring 12 is arranged to be slightly inclined with respect to the rotation axes 11a, 13a. The rotation axes 11a, 12a, 13a are connected to individual drive sources such as motors (not shown) via reducers 11b, 12b, 13b, respectively, and the disk 11, intermediate ring 12, and rotating ring 13 can each be driven to rotate independently.

The intermediate ring 12 and the upper part of the rotating ring 13 are formed with conveying surfaces 12c and 13c along the circumferential direction, respectively. The conveying surface 13c of the rotating ring 13 is covered on the radially outer side by a ring-shaped protrusion 13d.

The second conveying device 20 includes a first pulley 21 and a second pulley 22, whose respective rotating shafts 21a, 22a are arranged horizontally, an endless belt body 23 wound around the first pulley 21 and the second pulley 22, and a guide member 24 arranged along the conveying direction of the belt body 23. The diameter of the second pulley 22 is smaller than the diameter of the first pulley 21. The straight portion of the belt body 23 located between the first pulley 21 and the second pulley 22 is arranged horizontally above the first pulley 21 and the second pulley 22 to form a straight conveying path 2a, while being inclined below the first pulley 21 and the second pulley 22.

As shown in FIG. 2, the first pulley 21 is configured by two disks 21b, 21c connected by a rotating shaft 21a with a gap between them. The second pulley 22, like the first pulley 21, also has two disks connected by a rotating shaft 22a with a gap between them. In this embodiment, the first pulley 21 is a driving pulley connected to a drive motor (not shown), and the second pulley 22 is a driven pulley, but the first pulley 21 may be a driven pulley and the second pulley 22 may be a driving pulley.

The belt body 23 has two belt-shaped conveyor belts 23a and 23b, which are wound around the disks 21b and 21c of the first pulley 21, respectively. Between the two conveyor belts 23a and 23b, an opening 23c consisting of a fine gap is formed over the entire circumference of the belt body 23. The conveyor belts 23a and 23b can be formed, for example, from flat belts made of a soft material such as silicone rubber, but V-belts, toothed belts, etc. may also be used.

As shown in FIG. 1, the guide member 24 has a straight portion 24a disposed immediately below the vicinity of the belt body 23 that extends horizontally along the conveying path 2a between the first pulley 21 and the second pulley 22, and arc portions 24b and 24c provided on both sides of the straight portion 24a in the conveying direction. Each of the arc portions 24b and 24c is inserted between two disks provided on the first pulley 21 and the second pulley 22, and is formed to curve in an arc along the belt body 23 that is wrapped around the first pulley 21 and the second pulley 22.

2, the guide member 24 is formed in a hollow cylindrical shape, and a slit-shaped suction section 25 is formed along the opening 23c at the portion where the guide member 24 faces the opening 23c of the belt body 23. The inside of the guide member 24 can be depressurized by operating a vacuum pump (not shown), and the tablet P can be sucked into the suction section 25 through the opening 23c of the belt body 23, so that the tablet P can be transported together with the belt body 23 while being adsorbed to the belt body 23. In this embodiment, the opening 23c of the belt body 23 is formed continuously along the longitudinal direction between the two conveyor belts 23a and 23b, but the belt body 23 may be a single belt, and circular, elliptical, slit-shaped, or other openings may be formed intermittently along the longitudinal direction of the belt body.

Figure 4 is an enlarged plan view showing the vicinity of the conveying path 2a in Figure 1. As shown in Figure 4, the detection unit 30 is composed of a transmission type photoelectric sensor equipped with a light projecting unit 31 and a light receiving unit 32 arranged on both sides of the conveying path 2a in the horizontal direction, and a detection signal of the tablet P is generated while the light reception at the light receiving unit 32 is blocked by the tablet P passing between the light projecting unit 31 and the light receiving unit 32. The detection unit 30 may be other sensors such as a laser sensor, a reflective photoelectric sensor, a fiber sensor, a proximity sensor, etc. that can detect the tablet P conveyed by the conveying unit 2. The detection unit 30 may also be a camera such as a line camera or an area camera equipped with an imaging element such as a CCD or CMOS. When the detection unit 30 is a camera, the imaging direction of the tablet P can be, for example, a vertical direction or a horizontal direction.

The return unit 40 is disposed downstream of the detection unit 30 in the conveying direction in the vicinity of the conveying path 2a, and can selectively return the tablet P to the first conveying device 10 by injecting compressed air at the tablet P conveyed on the conveying path 2a. The tablet P that has been released from the conveying path 2a by the operation of the return unit 40 falls directly or via a chute (not shown) onto the first conveying device 10 disposed below the conveying path 2a, and is conveyed so as to pass through the detection unit 30 again. The configuration and arrangement of the return unit 40 are not particularly limited as long as it is possible to selectively return the tablet P that has passed through the detection unit 30 to the conveying path 2a upstream of the detection unit 30 in the conveying direction. For example, the return unit 40, which is composed of a pusher or the like that physically presses the tablet P on the conveying path 2a, can be disposed so that the tablet P falls onto the first conveying device 10 when it is activated.

As shown in the block diagram of FIG. 5, the transport state detection device 100 further includes a control unit 50. The control unit 50 controls the operation of the transport unit 2, the detection unit 30, and the return unit 40.

As shown in Figures 1 to 5, the printing device 1 of this embodiment includes a printing unit 60, a print inspection unit 70, and a sorting damper 80 in addition to the above-mentioned transport state detection device 100. The printing unit 60, the print inspection unit 70, and the sorting damper 80 are sequentially provided downstream in the transport direction of the return unit 40 near the transport path 2a. The operation of the printing unit 60, the print inspection unit 70, and the sorting damper 80 is controlled by the control unit 50.

The printing unit 60 is a laser printing device that can mark letters, numbers, symbols, figures, etc. by heating and modifying the surface of the tablet P transported to a specified position by scanning a laser spot. The printing unit 60 may also be another printing device, such as an inkjet printing device.

Next, the operation of the printing device 1 having the above configuration will be described. By supplying a plurality of tablets P onto the disk 11 while the disk 11, intermediate ring 12, and rotating ring 13 of the first conveying device 10 are rotated in the same direction, the tablets P are subjected to centrifugal force and move to the conveying surface 13c of the rotating ring 13 via the conveying surface 12c of the intermediate ring 12. In this way, the tablets P can be aligned in a line on the conveying surface 13c so that the longitudinal direction of the tablets P is along the circumferential direction of the rotating ring 13, and the tablets P can be conveyed in the rotation direction of the rotating ring 13 (the direction of the arrow D1 in FIG. 3). It is preferable that the rotation speeds of the disk 11, intermediate ring 12, and rotating ring 13 are each set so that the rotation speed of the disk 11 is the slowest and the rotation speed of the rotating ring 13 is the fastest, which can promote reliable alignment and conveyance of the tablets P by the rotating ring 13.

The first conveying device 10 may be configured to align the tablets P on the conveying surface 13c of the rotating ring 13 and convey them in the rotation direction of the rotating ring 13. For example, the intermediate ring 12 may not be provided, and the rotation axes of the disk 11 and the rotating ring 13 may be tilted relative to each other, so that the tablets P supplied onto the disk 11 are moved directly to the conveying surface 13c of the rotating ring 13. The rotation axis 13a of the rotating ring 13 is preferably arranged along the vertical direction as in this embodiment, but may be arranged to extend in the up-down direction. For example, the rotation axis 13a may be slightly tilted relative to the vertical direction.

The tablets P aligned and conveyed by the first conveying device 10 toward the second conveying device 20 are successively attracted to the belt body 23 near the bottom of the first pulley 21 by the suction of the suction section 25, and rise, and while still in the attracted state, are conveyed linearly above the first pulley 21 and the second pulley 22 in the direction of the arrow D2 in FIG. 3. In this way, the tablets P aligned by the first conveying device 10 are conveyed along the linear conveying path 2a while maintaining their aligned state by the second conveying device 20. At the transfer position of the tablets P from the rotating ring 13 to the belt body 23, it is preferable that the conveying direction by the rotating ring 13 and the conveying direction by the belt body 23 coincide as in this embodiment, so that the transfer of the tablets P can be performed reliably.

By making the conveying speed of the tablets P by the rotating ring 13 slower than the conveying speed of the tablets P by the belt body 23, the pitch (spacing) between the tablets P aligned and conveyed along the conveying path 2a toward the printing unit 60 can be increased. However, if the speed is too slow, the conveying efficiency of the tablets P decreases, so it is preferable to make the pitch of the tablets P as small as possible. For this reason, it may happen that some tablets P conveyed along the conveying path 2a are conveyed in a state of contact with each other because the pitch cannot be secured.

The detection unit 30 transmits a detection signal to the control unit 50 while the tablet P is passing through the conveying path 2a. Based on the detection by the detection unit 30, the control unit 50 calculates the length in the conveying direction, which is the appearance information of the tablet P, as an index value from the conveying speed of the tablet P and the duration of the detection signal, and compares it with a reference value.

When each tablet P is transported in a separate state as shown in FIG. 6(a), the index value calculated by the control unit corresponds to the transport direction length L1 of the tablet P, whereas when multiple tablets P are transported in a contacting state as shown in FIG. 6(b), the index value calculated by the control unit 50 is L2, which is the sum of the transport direction lengths L1 of the multiple tablets P that are in contact with each other. Therefore, by setting the reference value to an appropriate value between L1 and L2, the control unit 50 can correctly determine whether each tablet P is transported in a separate state.

The tablets P that have passed through the detection unit 30 are transported toward the printing unit 60. The control unit 50 allows tablets P that have been determined to be in a separated state to pass through the return unit 40, while the control unit 50 operates the return unit 40 to return tablets P that have been determined to be in a non-separated state (i.e., multiple tablets P that are in contact with each other) to the first conveying device 10, which is upstream of the detection unit 30 in the conveying direction. The tablets P returned to the first conveying device 10 will pass through the detection unit 30 again, and if they are determined to be in a separated state at this time, they will pass through the return unit 40 and be transported to the printing unit 60. The control unit 50 may not only calculate the length of the tablets P in the conveying direction, but also calculate the pitch between adjacent tablets P, and by checking that this pitch is within a predetermined range, it can be confirmed that each tablet P is being transported stably.

The tablets P printed by the printing unit 60 are imaged by the print inspection unit 70 and subjected to print inspection. The tablets P that have been judged to be good or bad by the print inspection are sorted into a good product box 81 and a bad product box 82 by the control unit 50 controlling the operation of the sorting damper 80.

According to the printing device 1 of this embodiment, the transport state detection device 100 can detect whether the tablets P are being transported in a separated state, so that printing errors such as misalignment, chipping, and omissions that occur when printing on tablets P in an unseparated state can be reliably prevented. Therefore, the pitch between tablets P can be minimized, thereby improving the transport efficiency and printing efficiency of tablets P.

In addition, the tablets P that are determined to be in a non-separated state are not discarded, but are returned to the upstream side of the detection unit 30 in the conveying direction by the operation of the return unit 40, and pass through the detection unit 30 again, so that printing can be performed by the printing unit 60 on all of the tablets P that are conveyed.

The control unit 50 of this embodiment obtains one-dimensional appearance information along the conveying direction based on detection by the detection unit 30 consisting of a sensor or camera as described above, and uses the conveying direction length based on this appearance information as an index value. However, it is also possible to obtain two-dimensional appearance information along a horizontal plane by capturing an image of the tablet P from above using the detection unit 30 consisting of a camera, which allows the separation state of the tablet P to be determined more accurately.

An example of an index value based on two-dimensional appearance information is the area of the tablet P. FIG. 7 shows an example of image data captured by the detection unit 30. When each tablet P is transported in a separate state as shown in FIG. 7(a), the index value calculated by the control unit 50 based on the image data is equal to the area S1 of each tablet P, whereas when multiple tablets P are transported in a contact state as shown in FIG. 7(b), the index value calculated by the control unit 50 is S2, which is the sum of the areas S1 of the multiple tablets P that are in contact with each other. Therefore, by setting the reference value to an appropriate value between S1 and S2, the control unit 50 can correctly determine whether each tablet P is transported in a separate state. When the area of the tablet P is used as the index value, the image of the tablet P may be extracted from the imaging data to calculate the index value, or the image of the background may be extracted from the imaging data to calculate the index value.

The index value based on the two-dimensional appearance information is not limited to the area of the tablet P, but may be, for example, the contour length of the tablet P, the fillet diameter of the tablet P, the circularity of the tablet P, or the degree of shape agreement. By comparing with a preset reference value, it is possible to determine whether the tablet P is being transported in a separated state. The fillet diameter of the tablet P may be, for example, the fillet diameter in the transport direction or the fillet diameter in a direction perpendicular to the transport direction. The degree of shape agreement may be calculated by pattern matching with a preset reference pattern. A combination of these index values may be used to determine the separated state.

The conveying unit 2 is not particularly limited as long as it is configured to randomly convey multiple tablets P in a row along the conveying path. For example, the conveying unit 2 shown in FIG. 1 may be configured to convey tablets P by directly adsorbing them to the outer peripheral surface of the first pulley 21 without using the belt body 23, and the detection unit 30, return unit 40, and printing unit 60 may be arranged in sequence along the circumferential direction of the first pulley 21. Alternatively, as disclosed in WO 2018/100980, a conveying unit that conveys tablets P by sandwiching them between one side of multiple conveying belts can be used.

Reference Signs List 1 Printing device 2 Conveying section 2a Conveying path 30 Detection section 40 Returning section 50 Control section 60 Printing section 100 Conveying state detection device P Tablet (edible body)

Claims (3)

A conveying unit that conveys a plurality of edible bodies in a row along a conveying path;
A detection unit that detects edible objects transported by the transport unit;
A control unit that acquires one-dimensional or two-dimensional appearance information of the edible body based on the detection of the detection unit, and compares an index value based on the appearance information with a reference value to determine whether each edible body is transported in a separated state ;
The detection unit is a camera,
The control unit is an edible body transport state detection device that sets at least one of the area, contour length, fillet diameter, circularity, and shape consistency of the edible body as the index value . Further provided is a return section which selectively returns the edible body that has passed through the detection section to the upstream side of the detection section in the conveying direction;
The device for detecting the transport state of edible bodies according to claim 1 , wherein the control unit operates the returning unit for a plurality of edible bodies determined to be in an unseparated state, and causes them to pass through the detection unit again. The transport state detection device for edible objects according to claim 1 or 2 ,
A printing device having a printing unit that prints on edible bodies that have been determined to be in a separated state.

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