WO2017187863A1 - Printing device - Google Patents

Abstract

The purpose of the present invention is to improve the quality of an image formed on a can body using a plurality of image formation units. A printing device 500 is provided with a moving unit 550 that moves while supporting can bodies 10. Additionally, the printing device is provided with a printing unit 520 that comprises a plurality of inkjet heads 11W, 11C, 11M, 11Y, 11K, and that performs printing on the can bodies 10 supported by the moving unit 550. Further, the printing device is provided with a moving mechanism 560 that causes the moving unit 550 to move by using a linear mechanism.

Description

Printing device

The present invention relates to a printing apparatus.

Patent Document 1 discloses a printing apparatus in which inkjet printing is performed in at least one inkjet printing station, and a plurality of inkjet heads are arranged in the inkjet printing station.

JP 2012-232771 A

When printing on the can body by moving the can body so as to pass through each of the plurality of image forming sections provided, the quality of the image formed is poor if the positioning accuracy of the can body with respect to each image forming section is poor Cause a decline.
An object of the present invention is to improve the quality of an image formed on a can using a plurality of image forming units.

Further, in the printing apparatus, the moving body holding the can body may be moved. However, if the weight of the moving body is large, the moving speed of the moving body is lowered and the printing efficiency is likely to be lowered. Also, if the weight of the moving body is large, the inertial force when the moving body stops increases, and the moving body may stop at a position different from the originally planned position.
Another object of the present invention is to reduce the weight of a moving body that moves while holding a can.

A printing apparatus to which the present invention is applied includes a moving body that moves while supporting a can body, a plurality of image forming units, a printing unit that performs printing on a can body supported by the moving body, and a plurality of printing apparatuses. And a moving unit that moves the moving body so that the moving body passes through each of the image forming units and moves the moving body using a linear mechanism.
Here, the printing unit can be characterized in that the moving body moves linearly.
In addition, the can body may be supported such that the axial direction of the can body supported by the moving body intersects the moving direction of the moving body.
In addition, the moving body moves along an annular path, and the can body supported by the moving body is arranged in a state of being moved closer to the outside than the inner side in the radial direction of the annular path. Can be a feature.
Furthermore, the moving body can be characterized by being configured to support a plurality of cans.
The moving unit moves the moving body using a linear mechanism when moving the moving body via each of the plurality of image forming units, and moves the moving body at a location other than the location where the plurality of image forming units are provided. The moving body can be moved at a location without using a linear mechanism.
In addition, a drive source for rotating the can supported by the moving body may be further provided, and the drive source may be installed at a location other than the moving body.

From another point of view, a printing apparatus to which the present invention is applied includes a driving mechanism that rotates a can body, and a moving body that moves while supporting the can body, and a can body that is supported by the moving body. And a driving source that is provided at a different location from the moving body and generates a driving force used by the driving mechanism of the moving body.
Here, a transmission mechanism that transmits the driving force generated by the driving source to the driving mechanism of the movable body may be further provided.
In addition, a plurality of the moving bodies are provided, and the transmission mechanism is in contact with the driving mechanisms provided in each of the plurality of moving bodies, and transmits a driving force to the plurality of driving mechanisms. can do.
Further, the transmission mechanism may be characterized in that a driving force is transmitted to the plurality of driving mechanisms using a belt member that circulates and moves.
Further, the transmission mechanism contacts the drive mechanism of the movable body to transmit a driving force to the drive mechanism, and the drive mechanism is driven from the opposite side of the transmission mechanism across the drive mechanism of the movable body. A support member that supports the mechanism may further be provided.
Moreover, it can be characterized by further comprising advancing / retreating means for advancing / retreating the transmission mechanism with respect to the drive mechanism of the moving body.
Further, the moving body is provided with a permanent magnet, the moving path of the moving body is provided with an electromagnet, and further provided with moving means for moving the moving body by controlling energization to the electromagnet. Can be a feature.

According to the present invention, it is possible to improve the quality of an image formed on a can using a plurality of image forming units.
Further, according to the present invention, it is possible to reduce the weight of the moving body that moves while holding the can body.

It is a top view of a printing apparatus. FIG. 2 is a cross-sectional view of a moving unit, a moving mechanism, etc. taken along line II-II in FIG. It is the figure which showed the other structural example of the printing part and the movement unit. (A), (B), (C) is the figure which showed the other structural example of the printing part. It is the figure which showed the other structural example of the mandrel drive mechanism. (A), (B) is a figure explaining a can body injection | throwing-in part. It is an enlarged view of the part shown by the code | symbol 6A of FIG. 6 (A). (A), (B) is a figure explaining a can body discharge part. It is the figure which showed the other structural example of the printing part. (A), (B) is the figure which showed the other example of arrangement | positioning of the inkjet head. It is the figure which showed the other structural example of the printing apparatus. It is the figure which showed the other structural example of the printing apparatus. It is the figure which showed the other structural example of the printing apparatus. It is the figure which showed the other structural example of the printing apparatus. It is sectional drawing of the XV-XV line | wire of FIG. It is the figure which showed the other structural example of the printing apparatus. It is a figure at the time of seeing a drying part from the arrow XVII direction of FIG. It is the figure which showed the structure of the can body test | inspection part. It is the figure which showed the other structural example of the mandrel. It is a schematic diagram at the time of looking at two adjacent inkjet heads.

Embodiments of the present invention will be described below with reference to the accompanying drawings.
FIG. 1 is a top view of the printing apparatus 500.
The printing apparatus 500 includes a can body loading unit 510 into which the can body 10 is loaded, a printing unit 520 that performs printing on the loaded can body 10, a drying unit 530 that performs drying of the printed can body 10, and a drying unit. A can body discharge part 540 for discharging the finished can body 10 is provided.
Further, the printing apparatus 500 is provided with a plurality of moving units 550 that move while supporting the can 10 and a moving mechanism 560 that functions as part of moving means for moving the moving unit 550. The moving mechanism 560 is formed in an annular shape.

The printing unit 520 is provided with a plurality of inkjet heads arranged side by side in the left-right direction in the drawing. Each of the ink jet heads can be regarded as an image forming unit that forms an image on the can 10. In the present embodiment, the printing unit 520 is provided with a plurality of image forming units.

Specifically, the printing unit 520 includes a first inkjet head 11W that ejects white ink, a second inkjet head 11C that ejects cyan ink, a third inkjet head 11M that ejects magenta ink, and yellow ink. A fourth inkjet head 11Y that ejects black ink and a fifth inkjet head 11K that ejects black ink are provided.
In the following description, the first inkjet head 11W to the fifth inkjet head 11K are simply referred to as “inkjet head 11” unless otherwise distinguished.

Here, the five inkjet heads 11 of the first inkjet head 11W to the fifth inkjet head 11K form an image on the can 10 using ultraviolet curable ink.
Further, in the present embodiment, in the process in which the can body 10 passes below the five inkjet heads 11, ink is ejected from above to the can body 10, and an image is formed on the can body 10. In other words, in this embodiment, the moving unit 550 passes through each of the plurality of inkjet heads 11 provided. In the course of this movement, ink is ejected from each inkjet head 11 to the can 10, and an image is formed on the can 10.
In this embodiment, the case where five inkjet heads 11 are provided is illustrated, but an inkjet head 11 that discharges ink of a special color such as a corporate color may be further provided.

The moving unit 550 as an example of the moving body moves at a predetermined moving speed, and the can 10 on the moving unit 550 rotates in the circumferential direction at a predetermined rotating speed.
In FIG. 1, five moving units 550 are shown, but the printing apparatus 500 is provided with more than five moving units 550, and these moving units 550 are circulated and moved by a moving mechanism 560. I do.

In the present embodiment, the timing at which the can 10 reaches each ink-jet head 11 is determined in advance, and each ink-jet head 11 starts ejecting ink in accordance with the timing at which the can 10 reaches the ink-jet head 11.
The first first ink jet head 11W is used to form a positioning mark on the surface of the can body 10, and the second and subsequent ink jet heads 11 read the positioning mark to thereby determine the ink ejection timing. You may decide.
Further, the determination of the discharge timing using the positioning marks may be performed by reading a dedicated mark to determine the discharge timing, or by reading a barcode or a recycle mark.

The drying unit 530 is disposed on the downstream side of the printing unit 520 and irradiates the can 10 with ultraviolet rays. Thereby, the image formed on the outer peripheral surface of the can 10 is cured. In the present embodiment, as described above, image formation on the can 10 is performed using ultraviolet curable ink. The drying unit 530 irradiates the can body 10 with ultraviolet rays to cure the image on the can body 10.
In forming an image on the can 10, a thermosetting ink may be used. In this case, the drying unit 530 applies heat to the can 10 and the image on the can 10 is changed. Harden.

2 is a cross-sectional view of the moving unit 550, the moving mechanism 560, and the like taken along the line II-II in FIG.
The moving mechanism 560 is provided with a guide member 561 for guiding the moving unit 550. The guide member 561 has an upper surface 561A, an outer peripheral surface 561B, and a lower surface 561C. An electromagnet 562 is provided inside the guide member 561.

In this embodiment, the moving unit 550 is moved using a linear mechanism.
As shown in FIG. 1, the printing apparatus 500 according to the present embodiment includes a control unit 600 that functions as part of a moving unit that moves the moving unit 550 by controlling energization of the electromagnet 562. The control unit 600 is configured by a program-controlled CPU (Central Processing Unit).
In the conveyance using the linear mechanism, the moving speed of the moving unit 550 can be easily changed. Further, in the conveyance using the linear mechanism, the moving unit 550 can be retracted.

In this embodiment, the moving unit 550 is stopped below each of the plurality of inkjet heads 11 to form an image on the can 10. In each inkjet head 11, the movement with respect to the inkjet head 11 is performed. If the positioning accuracy of the unit 550 is poor (the accuracy of the stop position is poor), the images of the respective colors formed on the can 10 are shifted, and the quality of the formed image is deteriorated. When the linear mechanism is used as in the present embodiment, for example, the accuracy of the stop position can be within 100 μm, and the shift of the image of each color can be reduced. When high-definition printing is required, position accuracy such as 50 μm to 100 μm or 10 μm to 30 μm can be obtained by devising such as reducing the moving speed of the moving unit 550.

As shown in FIG. 2, the movement unit 550 is provided with a guided member 551 that is guided by the guide member 561.
The guided member 551 includes an upper facing portion 551A facing the upper surface 561A of the guiding member 561, a side facing portion 551B facing the outer peripheral surface 561B of the guiding member 561, and a lower facing portion 551C facing the lower surface 561C of the guiding member 561. Is provided.
Further, a rotatable roll-shaped member 80 is installed between the guide member 561 and each of the upper facing portion 551A, the side facing portion 551B, and the lower facing portion 551C. The roll-shaped member 80 is fixed to the guided member 551. The roll-shaped member 80 reduces the sliding resistance between the guide member 561 and the guided member 551.

Furthermore, a unit-side magnet 90 made of a permanent magnet is provided on each of the upper facing portion 551A and the lower facing portion 551C of the guided member 551.
In the present embodiment, a propulsive force is generated in the moving unit 550 by the magnetic field generated by the electromagnet 562 provided on the guide member 561 and the unit-side magnet 90, and the moving unit 550 moves along the annular guide member 561. To do.

Furthermore, as shown in FIG. 2, the moving unit 550 includes a mandrel 70 that supports the can 10 and a support portion 75 that supports the mandrel 70. The support portion 75 is supported from below by a guided member 551. A mandrel motor M that rotates the mandrel 70 in the circumferential direction is provided inside the support portion 75.
The mandrel 70 is formed in a cylindrical shape. Further, the mandrel 70 is disposed in a lying state (a state along the horizontal direction). Thereby, in this embodiment, the can 10 is also arranged in the sleeping state.

Furthermore, in this embodiment, as shown in FIG. 1, a plurality of moving units 550 are provided. Further, the moving unit 550 passes through a region located below the plurality of inkjet heads 11 provided.
Furthermore, the moving unit 550 stops whenever it reaches the lower side of each inkjet head 11. Further, in the present embodiment, the mandrel motor M (see FIG. 2) is driven, and the mandrel 70 (see FIG. 2) rotates in the circumferential direction. Further, ink is ejected from the inkjet head 11.

Then, when the mandrel 70 rotates 360 ° after the ink discharge is started, the ink discharge is stopped. Thereby, an image is formed on the outer peripheral surface of the can 10.
The rotation of the mandrel 70 may be performed every time the mandrel 70 reaches the lower side of each inkjet head 11, or from the time when the moving unit 550 leaves the can body loading unit 510 to the time when the can body discharge unit 540 is reached. Meanwhile, the mandrel 70 may be continuously rotated.

Here, in the present embodiment, as shown in FIG. 1, the mandrel 70 is disposed sideways. Specifically, the mandrel 70 is arranged along a direction orthogonal (crossing) to the moving direction of the moving unit 550. In other words, in the present embodiment, the can body 10 is transported in a state where the axial direction of the can body 10 is orthogonal (crossed) to the moving direction of the moving unit 550.
In this case, the length L of the printing apparatus 500 can be reduced as compared with the case where the mandrel 70 is disposed along the moving direction of the moving unit 550. In other words, the total length of the moving path along which the moving unit 550 moves can be reduced.

In this case, the manufacturing cost of the printing apparatus 500 can be reduced. In the case of the printing apparatus 500 that performs printing in the process of moving the can body 10, the manufacturing cost of the printing apparatus 500 tends to increase according to the length of the movement path of the can body 10. In particular, in the case of linear conveyance, the manufacturing cost increases.
When the mandrel 70 is disposed sideways as in the present embodiment, the movement path of the movement unit 550 can be shortened, and the manufacturing cost of the printing apparatus 500 can be reduced.
Further, when the mandrels 70 are arranged sideways, the arrangement density of the moving units 550 in the moving direction of the moving units 550 can be increased, and the number of moving units 550 that can be installed can be increased.

Further, in the present embodiment, as shown in FIG. 1, the mandrel 70 and the inkjet head 11 are disposed sideways and are provided so as to protrude outward in the radial direction of the guide member 561. In other words, the mandrel 70 and the inkjet head 11 are arranged in a state of being closer to the outer side than the inner side in the radial direction of the guide member 561.

More specifically, in the present embodiment, the moving unit 550 moves along an annular movement path indicated by reference numeral 1A in the drawing, but the can body 10 is located outside the inner side in the radial direction of the annular movement path. It is arranged in the state brought to.
Maintenance of the mandrel 70 and the inkjet head 11 may be performed. In such a case, if the mandrel 70 and the inkjet head 11 are moved outward as in this embodiment, compared to the case where the mandrel 70 and the inkjet head 11 are moved toward the inner side, This maintenance is easy to perform.

In the present embodiment, as described above, the inkjet head 11 is disposed above the can body 10, and ink is ejected from above to the can body 10.
In this case, compared with the case where the inkjet head 11 is disposed on the side of the can body 10 or below the can body 10, the influence of gravity acting on the ink droplets ejected from the inkjet head 11 can be reduced. The accuracy of the ink adhesion position in the can 10 can be increased.

2 shows the case where the mandrel 70 and the inkjet head 11 are provided on the right side of the support portion 75 in the drawing, but the left side of the support portion 75 in the drawing as shown by reference numeral 2A in FIG. The mandrel 70 and the inkjet head 11 may be provided.
Further, the mandrel 70 and the inkjet head 11 may be provided on both the right and left sides of the support portion 75 in the drawing.

When the mandrel 70 and the inkjet head 11 are provided on the right side and the left side of the support part 75 (on both sides of the support part 75), the unit time is compared with the case where the mandrel 70 and the inkjet head 11 are provided only on one side of the support part 75. The number of cans 10 that can be printed per hit can be increased.
In addition, when the mandrel 70 is provided on both sides of the support portion 75, the left and right (left and right in FIG. 2) balance of the moving unit 550 is improved, and the moving unit 550 can be prevented from being inclined due to the weight of the mandrel 70.

In the case where the mandrels 70 are provided on both sides of the support portion 75, a mandrel motor M may be provided corresponding to each mandrel 70 (a mandrel motor M may be provided for each mandrel 70). Two mandrels 70 located on both sides may be rotated by one mandrel motor M (a plurality of mandrels 70 may be rotated).
Here, when two mandrels 70 are rotated by one mandrel motor M, for example, a transmission gear is installed between the mandrel motor M and the two mandrels 70, and the rotational driving force from the mandrel motor M is obtained. Is transmitted to each mandrel 70.

When the mandrel 70 is provided on both sides of the support portion 75, the direction of the can body 10 attached to the mandrel 70 is different. The two mandrels 70 located on both sides of the support portion 75 are different from each other in the direction in which the tip portion of the mandrel 70 faces. In such a case, the directions of the can bodies 10 to be mounted are also different.
Further, depending on the configuration of the transmission gear, the two can bodies 10 may rotate in the same direction or in the opposite directions.

In such a case, if the discharge control in the two inkjet heads 11 provided corresponding to the two can bodies 10 is performed with the same control, an image formed on one can body 10 is originally There is a possibility that the image differs from the planned image.
For this reason, when the mandrels 70 are provided on both sides of the support unit 75, image data that matches the orientation and rotation direction of the mandrel 70 is obtained by performing image processing such as rotation processing and reversal processing of image data used for printing. And generating an image on the can 10 using the image data.

Next, the moving mechanism 560 will be described.
As shown in FIG. 1, the guide member 561 provided in the moving mechanism 560 is formed in an annular shape. Further, the guide member 561 includes a first curved portion 571 having a curvature, a first straight portion 572 formed in a linear shape, a second curved portion 573 having a curvature, and a second straight portion 574 formed in a linear shape. Is provided.

The first straight part 572 and the second straight part 574 are arranged to be parallel to each other. Moreover, the 1st linear part 572 and the 2nd linear part 574 are arrange | positioned so that it may oppose.
Further, the first curved portion 571 connects one end portion of the first straight portion 572 and one end portion of the second straight portion 574. Further, the second curved portion 573 connects the other end portion of the first straight portion 572 and the other end portion of the second straight portion 574.
In the present embodiment, the first curve portion 571 is provided with a can body insertion portion 510. In addition, a printing unit 520 and a drying unit 530 are provided in the first straight part 572. Furthermore, a can body discharge portion 540 is provided in the second curved portion 573.

FIG. 3 is a diagram illustrating another configuration example of the printing unit 520 and the moving unit 550.
In this configuration example, three (a plurality) mandrels 70 are provided in one moving unit 550, and each moving unit 550 moves while holding three can bodies 10.
Furthermore, the printing unit 520 is provided with three inkjet heads 11 of the same color corresponding to the three mandrels 70. Specifically, three ink jet heads 11 are provided for each color.
In FIG. 3, the yellow fourth inkjet head 11Y and the black fifth inkjet head 11K are not shown, but in the yellow fourth inkjet head 11Y and the black fifth inkjet head 11K, there are also three. Inkjet head 11 is provided.

In this configuration example shown in FIG. 3, each moving unit 550 stops below the three inkjet heads 11 provided for each color.
In each moving unit 550, the three mandrels 70 (cans 10) are rotated, and ink is ejected from the three inkjet heads 11 that eject ink of the same color to each can 10. Is done. Thereby, an image is formed on the outer peripheral surface of the can 10 as described above.

In the configuration example shown in FIG. 3, the printing efficiency can be increased compared to the configuration of FIG. 1 in which printing is performed every time the moving unit 550 reaches the adjacent inkjet head 11.
Furthermore, in this configuration example, ink is ejected at the same timing in each of the three inkjet heads 11 that eject ink of the same color. Thereby, the process can be simplified as compared with the configuration in which each of the inkjet heads 11 has different ink ejection timings.

When a plurality of mandrels 70 are installed in the moving unit 550, it is preferable that the number of mandrels 70 is 2 to 8. If the number of mandrels 70 is nine or more, the weight of the moving unit 550 increases, and it may be difficult to control the position of the moving unit 550.
Specifically, when the weight of the moving unit 550 increases, the inertial force of the moving unit 550 when the moving unit 550 stops increases, and the stop position of the moving unit 550 tends to deviate from the original position.
When a plurality of mandrels 70 are installed in the moving unit 550, the preferred number of mandrels 70 is 2 to 4.

FIGS. 4A, 4 </ b> B, and 4 </ b> C are diagrams illustrating another configuration example of the printing unit 520.
4A is a top view, FIG. 4B is a view when the printing unit 520 is viewed from the direction of the arrow IVB in FIG. 4A, and FIG. FIG. 5 is a diagram when the printing unit 520 is viewed from the direction of an arrow IVC in FIG.

In the configuration example shown in FIG. 4, the moving unit 550 is not provided with the mandrel motor M.
In this configuration example, as shown in FIG. 4B, the mandrel 70 provided in each moving unit 550 is driven by a mandrel driving mechanism 20 provided at a location different from the moving unit 550.
The mandrel drive mechanism 20 includes an endless belt member 21 that circulates, a drive roll 22 that is disposed in contact with the belt member 21 and rotates the belt member 21, and a belt motor 23 that rotates the drive roll 22. With. Furthermore, although illustration is omitted, the mandrel driving mechanism 20 includes a tension roll that stretches the belt member 21 from the inside.
Here, the belt motor 23 as an example of the driving source generates a driving force for rotating the can body 10 supported by the moving unit 550. This driving force is transmitted to the can body 10 via the belt member 21 and the like.

The belt member 21 is disposed in contact with the mandrel 70 as shown in FIG. More specifically, each moving unit 550 is provided with a gear arranged coaxially with the mandrel 70 (hereinafter referred to as “mandrel side gear 71”), and the belt member 21 includes the mandrel side gear. 71 is engaged.
A gear (uneven portion) is formed on the outer peripheral surface of the belt member 21. In this embodiment, the gear of the belt member 21 meshes with the mandrel side gear 71, and the belt member 21 that circulates from the mandrel 70 to the mandrel 70. The rotational driving force is transmitted.

In the present embodiment, when the moving unit 550 reaches the printing unit 520 (see FIG. 4B), the mandrel side gear 71 provided in the moving unit 550 contacts the belt member 21, and the mandrel side gear 71 and the belt member are contacted. Engagement with 21 occurs. As a result, the mandrel 70 can be rotated in the circumferential direction.

In other words, in the present embodiment, the mandrel side gear 71 and the mandrel 70 function as a drive mechanism for rotating the can body 10, and the drive roll 22 and the belt member 21 are driven by the belt motor 23. It functions as a transmission mechanism that transmits to the drive mechanism. In the present embodiment, the mandrel side gear 71 that functions as a part of the drive mechanism contacts the belt member 21 that functions as a part of the transmission mechanism, whereby the mandrel 70 rotates in the circumferential direction.

In the present embodiment, as shown in FIG. 4C, the belt member 21 contacts the upper part of the mandrel side gear 71, but the belt member 21 contacts the lower part of the mandrel side gear 71. It is good also as composition to do.
In the present embodiment, as shown in FIG. 4B, the mandrel side gear 71 contacts the outer peripheral surface of the belt member 21, but the mandrel side gear 71 contacts the inner peripheral surface of the belt member 21. Also good. In this case, the printing apparatus 500 can be downsized as compared with the case where the mandrel side gear 71 is in contact with the outer peripheral surface of the belt member 21.
Further, in the present embodiment, the configuration of the printing unit 520 has been described. However, the mandrel driving mechanism 20 is also provided in the drying unit 530 (see FIG. 1) and the like, and the can body 10 is also surrounded by the drying unit 530 and the like. Rotate in the direction.

In the configuration example shown in FIG. 4, the accuracy of the stop position of the moving unit 550 can be increased, and the number of drive sources can be reduced.
When the mandrel motor M is installed in each of the moving units 550, the gravity of the moving unit 550 increases, and the inertial force when the moving unit 550 stops is increased. In such a case, the accuracy of the stop position of the moving unit 550 may be reduced.

On the other hand, in the present embodiment, a driving source is provided separately from the moving unit 550, and driving force is supplied to the moving unit 550 from the outside of the moving unit 550.
In such a configuration, the moving unit 550 can be reduced in weight, and the inertial force when the moving unit 550 stops is reduced. In this case, the accuracy of the stop position of the moving unit 550 can be improved.

Further, in the configuration in which each of the moving units 550 is provided with the mandrel motor M, the number of the mandrel motors M corresponding to the number of the moving units 550 is provided, which causes an increase in the driving source and the manufacturing cost of the printing apparatus 500. Will increase.
On the other hand, in the configuration example shown in FIG. 4, the drive source is shared, and the drive source can be reduced. In this case, the manufacturing cost of the printing apparatus 500 can be reduced.

In the present embodiment, the case where the belt members 21 extending along the moving direction of the moving unit 550 are installed and the mandrels 70 are rotated has been described. You may go.
For example, a rotating gear (not shown) (hereinafter referred to as “rotating gear”) is installed corresponding to each of the inkjet heads 11, and the mandrel side gear 71 is engaged with the rotating gear. Each mandrel 70 may be rotated.
In this case, each rotation gear can be rotated by a common drive source, or may be rotated by a drive source prepared for each rotation gear.

The belt member 21 and each rotation gear may be rotated while the moving unit 550 is moving, or may be stopped and after the moving unit 550 stops below the inkjet head 11. , Rotation may be started.
When the belt member 21 is always rotated, the driving force is supplied from the belt member 21 to the mandrel 70 even when the moving unit 550 moves between the inkjet heads 11. In this case, the moving unit 550 moves while the mandrel 70 on the moving unit 550 rotates.

It should be noted that rotating the plurality of mandrels 70 with the belt member 21 improves the quality of the image formed on the can 10 rather than rotating the mandrels 70 using the rotation gear provided for each mandrel 70 individually. Easy to improve.
When the plurality of mandrels 70 are rotated by the belt member 21, it is possible to reduce the displacement of the position of each color image and improve the quality of the formed image.

When the rotation gear is provided corresponding to each mandrel 70, there is a possibility that the respective positions of the rotation gears are shifted due to the dimensional tolerance of the members. In this case, the position of the mandrel 70 (the position of the mandrel 70 with respect to the inkjet head 11) when the mandrel side gear 71 is engaged with the rotating gear tends to be different for each rotating gear with which the mandrel side gear 71 is engaged. In such a case, a shift tends to occur between the images of the respective colors formed on the can 10.
On the other hand, when the continuous belt member 21 is used, since the mandrel 70 is synchronized, the position of the belt member 21 is less likely to change, and the image of each color formed on the can body 10 is less likely to shift.

Another configuration example will be further described.
In the configuration example shown in FIG. 5 (a diagram illustrating another configuration example of the mandrel driving mechanism 20), the belt member 21 that applies a rotational driving force to the mandrel side gear 71 on both the upper and lower sides of the mandrel side gear 71 in the drawing. Is installed.
In the case of the configuration example shown in FIG. 4C, the mandrel side gear 71 is pressed from above by the belt member 21, and a load that tilts the mandrel 70 acts on the mandrel side gear 71.

On the other hand, in the configuration example shown in FIG. 5, the mandrel side gear 71 is supported from below by the belt member 21 (the lower belt member 21 in the figure) as an example of the support member, and FIG. Compared to the configuration shown, the mandrel 70 is less likely to tilt.
In other words, in the configuration example shown in FIG. 5, the upper belt member 21 in the drawing can be regarded as a transmission mechanism that transmits the rotational driving force to the mandrel side gear 71. In this configuration example, the mandrel side gear 71 is sandwiched and the mandrel side gear 71 is supported by the belt member 21 (the lower belt member 21 in the drawing) from the side opposite to the installation side of the transmission mechanism. .

In addition, although FIG. 5 demonstrated the case where the belt member 21 was installed in the upper and lower sides of the mandrel side gear 71 in the drawing, the rotating gear was installed instead of the belt member 21 (mandrel side gear 71). Rotating gears may be installed above and below 71), and the mandrel side gear 71 may be rotated and the mandrel side gear 71 supported by the rotating gear.

Further, the belt member 21 may be installed on one of the upper and lower sides of the mandrel side gear 71 in the drawing, and the rotation gear may be installed on the other.
In addition, a configuration in which a rotational driving force is not applied to the mandrel-side gear 71 from one of the two members (the belt member 21 and the rotating gear) arranged above and below the mandrel-side gear 71 in the drawing. It is good.
In this case, this one member mainly supports the mandrel side gear 71. In this case, the one member rotates following the mandrel side gear 71.

Further, as shown in FIG. 4B, an advance / retreat mechanism 89 is provided as an example of an advance / retreat mechanism for advancing / retreating the mandrel drive mechanism 20 relative to the moving unit 550 (mandrel side gear 71). The mandrel drive mechanism 20 may be moved up and down to advance and retract the mandrel drive mechanism 20 with respect to the moving unit 550.
Specifically, for example, while the moving unit 550 is moving (while the moving unit 550 is moving between the inkjet heads 11), the mandrel driving mechanism 20 is retracted upward. . When the moving unit 550 stops below the inkjet head 11, the mandrel driving mechanism 20 is lowered and the belt member 21 of the mandrel driving mechanism 20 is brought into contact with the mandrel side gear 71.

In this case, the belt member 21 may be rotated after the belt member 21 comes into contact with the mandrel side gear 71, or the belt member 21 is always rotated and the rotating belt member 21 is rotated. 71 may be contacted.
Further, in the configuration example shown in FIG. 4B, the configuration in which the entire mandrel driving mechanism 20 moves up and down has been described. However, the portion indicated by reference numeral 4E in FIG. 4B (the lower side of the belt member 21). It is good also as a structure to which only the part located in () is moved up and down.
The same applies to the rotating gear, and the rotating gear may be moved up and down to contact the rotating gear to the mandrel side gear 71 and to retract the rotating gear from the mandrel side gear 71.

If the mandrel side gear 71 of the moving unit 550 that has moved from the upstream side contacts the belt member 21 that rotates and the rotating gear that rotates, the impact acting on the moving unit 550 increases, or the mandrel side Wear of the gear 71 and the like is easily promoted.
When the belt member 21 and the rotating gear come into contact with the moving unit 550 that is stopped as in the present embodiment, the impact acting on the moving unit 550 can be made smaller, and the mandrel side gear 71 and the like can be reduced. Wear can be suppressed.

In the configuration example shown in FIG. 4A, one inkjet head group is configured by three inkjet heads 11 provided for each color, and the intervals between the inkjet heads 11 are all the head interval L1. The separation distances between the adjacent inkjet head groups are the separation distance L2, and all the distances L1 between the inkjet heads 11 and the separation distances L2 between the adjacent inkjet head groups are equal.
In this case, the inkjet heads 11 are positioned at equal intervals, and the movement distances when moving each moving unit 550 to the adjacent inkjet head group are equal in each moving unit 550, and the moving unit 550 is moved. It is possible to simplify the control when making it.
Here, it is preferable that the head distance L1 and the separation distance L2 be the shortest distance within a range in which the cans 10 and the inkjet heads 11 do not interfere with each other because the moving distance is shortest.
Furthermore, at this time, for example, when the can 10 moves from the position of the inkjet head 11W to the position of the inkjet head 11C, in other words, when the can 10 moves a distance of (2 × L1 + L2), the inkjet head 11W It is preferable that the rotation speed of the can body 10 is set so that the printing start point of the can body 10 at the position facing the inkjet head 11C. If it does so, the waiting time until the said printing start point of the can 10 comes to the position which opposes the inkjet head 11C by rotation by the position of the inkjet head 11C is lost.

FIGS. 6A and 6B are diagrams illustrating the can body charging unit 510. FIG. FIG. 7 is an enlarged view of a portion indicated by reference numeral 6A in FIG.
As shown in FIG. 6A, the can body insertion portion 510 of the present embodiment is provided in the first curved portion 571 of the moving mechanism 560.
The can body 10 that has not yet been printed is sequentially transported to the can body loading section 510 by the transport mechanism 400. Then, as shown by an arrow 6B in FIG. 6A, the can body 10 is pushed out toward a mandrel 70 provided in the moving unit 550 (it is pushed out by an unillustrated push-out mechanism). A mandrel 70 is inserted inside. Thereby, support of can 10 by mandrel 70 is started.

In the can body charging unit 510, air in the mandrel 70 is sucked from the rear end side of the mandrel 70 (the end side opposite to the front end where insertion into the can body 10 is started), When the can body 10 is mounted on the mandrel 70, the can body 10 is sucked by the mandrel 70.
Specifically, as shown in FIG. 7, a suction device 410 is provided in the can body charging unit 510, and the suction device 410 is connected to the moving unit 550 in the can body charging unit 510. The air inside the mandrel 70 is sucked by the suction device 410. As a result, the can 10 is sucked by the mandrel 70, and the mandrel 70 enters the inside of the can 10.
As shown in FIG. 6B, when a plurality of mandrels 70 are provided in the moving unit 550, the number of can bodies 10 corresponding to the number of installed mandrels 70 is advanced toward the mandrels 70. Let

FIGS. 8A and 8B are diagrams illustrating the can body discharge portion 540. FIG.
As shown in FIG. 8A, the can body discharge portion 540 is provided on the second curved portion 573 of the moving mechanism 560.
In the can body discharge portion 540, compressed air is supplied into the mandrel 70 from the rear end side of the mandrel 70 using an air supply device (not shown). Thereby, the can 10 is pressed by the compressed air, and the can 10 is detached from the mandrel 70. In addition, the can 10 removed from the mandrel 70 is transported to the next step by a transport mechanism (not shown).
As shown in FIG. 8B, when a plurality of mandrels 70 are provided in the moving unit 550, compressed air is supplied into each mandrel 70, and the can body 10 is removed from all the mandrels 70. Remove.

Here, in the present embodiment, as shown in FIG. 1, the printing unit 520 is provided in the first straight portion 572 of the moving mechanism 560. If the printing unit 520 is provided in the first curved portion 571 or the second curved portion 573, the position of the can body 10 with respect to the inkjet head 11 is likely to fluctuate, and the quality of the formed image may be reduced.
On the other hand, when the printing unit 520 is provided in the first linear portion 572, image formation on the can 10 is performed in the process in which the moving unit 550 moves linearly. In this case, fluctuations in the position of the can body 10 with respect to the inkjet head 11 are less likely to occur, and a reduction in the quality of the image formed on the can body 10 can be suppressed.

FIG. 9 is a diagram illustrating another configuration example of the printing unit 520.
In this configuration example, a plurality of inkjet heads 11 are arranged on one mandrel 70 (can body 10). Specifically, three mandrels 70 are arranged in the moving unit 550 located on the most upstream side in the drawing.
Above each mandrel 70 included in the three mandrels 70, two inkjet heads 11 of a white first inkjet head 11W and a cyan second inkjet head 11C are installed.

Further, in the drawing, in the moving unit 550 located second from the upstream side, two ink jet heads 11 of a magenta third ink jet head 11M and a yellow fourth ink jet head 11Y are disposed above each of the three mandrels 70. is set up.
In the moving unit 550 located on the most downstream side, the black fifth inkjet head 11K is installed above each of the three mandrels 70. At this time, in the case where the inkjet head 11 that discharges ink of a special color such as a corporate color is provided, it may be installed together with the black fifth inkjet head 11K at the position of the moving unit 550 located on the most downstream side.

In this configuration example, as described above, image formation is performed on one can 10 using a plurality of inkjet heads 11. Further, in this configuration example, image formation is performed on each of the plurality of cans 10 provided in one moving unit 550 using the same color ink.
Specifically, for example, in the moving unit 550 located on the most upstream side in the figure, three can bodies 10 are provided. However, image formation is performed using two-color inks of white and cyan.

In the configuration example shown in FIG. 1, it is necessary to stop and restart the movement unit 550 every time an image for one color is formed, and it is necessary to stop and restart the movement five times in total. is there. In the configuration example shown in FIG. 9, it is only necessary to stop three times and restart the movement, and the printing efficiency can be improved.

In FIG. 9, the case where two inkjet heads 11 are installed on one mandrel 70 has been described as an example, but FIG. 10A (a diagram illustrating another arrangement example of the inkjet head 11). , (B), three or more inkjet heads 11 may be installed on one mandrel 70 (can body 10).
Further, when a plurality of inkjet heads 11 are installed on one mandrel 70 as described above, as shown in FIGS. 10A and 10B, the plurality of inkjet heads 11 are connected to the mandrel 70 ( An advancing / retracting mechanism 800 for advancing / retreating the can body 10) may be provided.

Specifically, in the present embodiment, as shown by an arrow 10A in FIG. 10A, the can body 10 (mandrel 70) moves in a straight line along the horizontal direction. There is a possibility that the most upstream ink jet head 11 (ink jet head 11 indicated by reference numeral 10B) and the can 10 may interfere with each other.
In order to avoid this interference, the can body 10 may be moved so as to pass through a portion away from the ink jet head 11 as indicated by an arrow 10C. In this case, the can body 10 is separated from the ink jet head 11. There is a risk that the quality of the image will deteriorate.

On the other hand, if the advance / retreat mechanism 800 is provided, interference between the ink jet head 11 and the can body 10 can be avoided, and the can body 10 can be disposed near the ink jet head 11.
The processing by the advance / retreat mechanism 800 will be described in detail. When the can body 10 is transported, the inkjet head 11 is moved in the direction indicated by the arrow 10X in FIGS. The inkjet head 11 is retracted to the side away from the movement path.

When the can body 10 stops below the ink jet head 11, the ink jet head 11 is advanced to the can body 10 as indicated by an arrow 10Y. Thereafter, ink discharge from the inkjet head 11 is started, and image formation on the can 10 is performed.
When the image formation is completed, the inkjet head 11 is moved in the direction indicated by the arrow 10X, and the inkjet head 11 is retracted. And the conveyance of the can 10 is restarted.
Thereby, interference between the inkjet head 11 and the can body 10 can be avoided, and the inkjet head 11 can be disposed near the can body 10.
The advance / retreat mechanism 800 can be configured by a known technique, for example, using a motor, a solenoid, or the like.

In addition, although FIG. 10 demonstrated the case where the inkjet head 11 was moved (it moved up and down), you may move the can 10 up and down.
Further, as shown in FIG. 10B, when five ink jet heads 11 are installed above one can body 10, printing on the can body 10 is completed only by rotating the can body 10 once. be able to.

FIG. 11 is a diagram illustrating another configuration example of the printing apparatus 500.
In this configuration example, the moving mechanism 560 is formed in a substantially rectangular shape.
Further, in this configuration example, an abnormality detection unit 511 and an abnormal product discharge unit 512 are provided between the can body insertion unit 510 and the printing unit 520. Furthermore, an outer surface coating unit 535 is provided between the drying unit 530 and the can body discharging unit 540.

The abnormality detection unit 511 detects an abnormality of the can body 10. More specifically, an abnormality such as a shape of the can body 10, a scratch or a dent, or an abnormality in the mounting of the can body 10 is detected. For example, when a part of the can body 10 protrudes outside the outer peripheral surface of the can body 10, this protrusion is detected, and it is detected that there is an abnormality in the can body 10.
In the abnormality detection unit 511, for example, a so-called transmission type sensor is installed, and a light emitting unit and a light receiving unit are provided. When the protrusion part arises in the can 10 as mentioned above, the light which goes to a light-receiving part from this light emission part by this protrusion part is interrupted | blocked. Thereby, the abnormality of the can 10 is detected. Similarly, the scratches or dents on the can body 10 or abnormal mounting of the can body 10 may be detected using various sensors.

The abnormal product discharge unit 512 is configured in the same manner as the can body discharge unit 540, and supplies compressed air to the inside of the mandrel 70 holding the can body 10 when the abnormal can body 10 is conveyed. To do. Thereby, the can 10 is detached from the mandrel 70. In addition, the can body 10 (can body 10 having an abnormality) detached from the mandrel 70 is transported to a predetermined location by a transport mechanism (not shown).
The outer surface coating portion 535 applies a paint to the outer peripheral surface of the can body 10 to form a protective layer on the outer peripheral surface of the can body 10. The outer surface coating portion 535 is provided with a roller (not shown) that comes into contact with the outer peripheral surface of the can body 10, and using this roller, paint is applied to the outer peripheral surface of the can body 10 to form a protective layer. .

FIG. 12 is a diagram illustrating another configuration example of the printing apparatus 500.
In this configuration example, two sets of basic configurations including a can body charging unit 510, a printing unit 520, a drying unit 530, and a can body discharging unit 540 are provided. Thereby, in this configuration example, the number of cans 10 that can be printed per unit time can be increased.
Specifically, the basic configuration of the first set (can body insertion unit 510, printing unit 520, drying unit 530, can body discharge unit 540) is located above the straight line 12A extending in the left-right direction in the drawing. ing.
Here, similarly to the above, in this first set of basic configurations, the can body insertion portion 510 is located at the first curved portion 571, the printing portion 520 and the drying portion 530 are located at the first straight portion 572, The can body discharge portion 540 is located at the second curved portion 573.

Further, the second set of basic components (can body loading unit 510, printing unit 520, drying unit 530, can body discharging unit 540) is located below the straight line 12A in the figure.
Here, in the second set of basic configurations, the can body insertion portion 510 is located at the second curved portion 573, the printing portion 520 and the drying portion 530 are located at the second straight portion 574, and the can body discharge portion. 540 is located in the first curved portion 571.

In this configuration example shown in FIG. 12, the number of cans 10 that can be printed per unit time is doubled as a result of providing two basic configurations.
In this configuration example, the case where two sets of basic configurations are provided has been described, but this is an example, and three or more sets of basic configurations may be provided. In addition, the abnormality detection unit 511, the abnormal product discharge unit 512, and the outer surface coating unit 535 illustrated in FIG. 11 may be installed in each of the basic configurations.

FIG. 13 is a diagram illustrating another configuration example of the printing apparatus 500.
In the configuration example described above, the guide member 561 is installed over the entire circumference of the circulation path along which the movement unit 550 moves, and the movement unit 550 is moved using the linear mechanism over the entire circumference.
By the way, the installation range of the moving mechanism 560 (the guide member 561 thereof) is not limited to the entire circumference, but may be a part of the circulation path as shown in FIG. In this configuration example shown in FIG. 13, a part of the moving mechanism 560 is replaced with a belt conveyance device 750. In other words, in this configuration example, the printing unit 520 and the like move the moving unit 550 using a linear mechanism, but the second linear portion 574 moves the moving unit 550 without using the linear mechanism.

The belt conveying device 750 is provided with a circulation belt 751 that circulates, a tension roll (not shown) that stretches the circulation belt 751, and a drive motor (not shown) that rotates the tension roll.
A moving rail 750C is provided between the upstream portion 750A of the belt conveying device 750 and the moving mechanism 560 and between the downstream portion 750B of the belt conveying device 750 and the moving mechanism 560.

In this configuration example, when the moving unit 550 moves to the upstream side of the belt conveying device 750, the moving rail is placed inside the U-shaped guided member 551 (see FIG. 2) provided in the moving unit 550. 750C enters. The moving unit 550 is guided by the moving rail 750 </ b> C, and the moving unit 550 moves to the belt conveyance device 750. The moving unit 550 is placed on the circulation belt 751.

Thereafter, the moving unit 550 is moved by the circulation belt 751 in the right direction in the figure, and then supported again by the guide member 561 of the moving mechanism 560.
Specifically, the moving unit 550 is supported by the moving rail 750 </ b> C after moving in the right direction in the figure while being placed on the circulation belt 751. Next, the moving unit 550 is guided by the moving rail 750 </ b> C, and the moving unit 550 reaches the moving mechanism 560. The moving unit 550 is again supported by the guide member 561 provided in the moving mechanism 560.

In the printing unit 520 and the like, it is necessary to control the position of the moving unit 550. However, in the portion where the functional unit is not particularly installed, such as the second linear portion 574, the position control of the moving unit 550 is not necessary. . Furthermore, since the moving mechanism 560 moves the moving unit 550 using a linear mechanism, if the moving mechanism 560 is provided on the entire circumference, the manufacturing cost of the printing apparatus 500 increases.
For this reason, in this configuration example, the moving mechanism is provided at a location on the opposite side of the location where the printing unit 520 is provided (at a location where a functional unit for processing the can 10 is not provided). A part of 560 is replaced with a cheaper belt conveyance device 750.

In FIG. 13, the case where the belt conveyance device 750 is installed only in the second linear portion 574 has been described, but the belt conveyance device 750 may be provided in the first curved portion 571 or the second curved portion 573. Further, for example, the first linear portion 572 and the second linear portion 574 use a linear mechanism to move the moving unit 550, and the first curved portion 571 and the second curved portion 573 use the belt conveyance device 750. The movement unit 550 may be moved.

FIG. 14 is a diagram illustrating another configuration example of the printing apparatus 500. 15 is a cross-sectional view taken along line XV-XV in FIG. FIG. 14 shows a state where the printing apparatus 500 is viewed from the side of the printing apparatus 500. In FIG. 14, the mandrel driving mechanism 20 shown in FIG. 4 is not shown.

As shown in FIG. 14, in this configuration example, the printing apparatus 500 is arranged vertically. Specifically, in the printing apparatus 500, the first straight part 572 is located above and the second straight part 574 is located below the first straight part 572.
In FIG. 1 and the like, the horizontal printing apparatus 500 is shown. However, the printing apparatus 500 is not limited to horizontal installation, and may be installed vertically as shown in FIG.

When the printing apparatus 500 is placed vertically, as shown in FIG. 15, the moving unit 550 is placed on the outer peripheral surface 561 </ b> B of the guide member 561 provided in the moving mechanism 560 when positioned in the first linear portion 572. Become.
Further, the mandrel 70 on the moving unit 550 is arranged in the horizontal direction as shown in FIG. 14 and as shown in FIG. Specifically, the mandrel 70 is arranged along a direction orthogonal (crossing) to the moving direction of the moving unit 550.

As in this configuration example, when the printing apparatus 500 is arranged vertically, the area occupied by the printing apparatus 500 is smaller than when the printing apparatus 500 is arranged horizontally.
On the other hand, in the case of vertical installation, it becomes difficult to utilize the second straight portion 574 (see FIG. 14). In the case of landscape orientation, as shown in FIG. 12, the printing unit 520 or the like can be installed in the second straight line portion 574, but in the case of portrait installation, the printing unit 520 or the like is installed in the second straight line portion 574. It becomes difficult.

Note that the various configurations described above can also be applied to the vertical printing apparatus 500 even in the vertical printing apparatus 500.
For example, a configuration in which a plurality of mandrels 70 are installed in the moving unit 550 (see FIG. 3A), a configuration in which the mandrels 70 are driven by an external drive source (see FIG. 4B), an abnormality detection unit 511, The configuration (see FIG. 11) in which the abnormal product discharge unit 512 and the outer surface coating unit 535 are provided can also be applied to the vertical printing apparatus 500.
In addition, a configuration in which a plurality of sets of printing units 520 and the like are provided (see FIG. 12), a configuration in which a plurality of inkjet heads 11 are installed above one mandrel 70 (see FIG. 9), and a configuration in which the inkjet heads 11 advance and retract (see FIG. 10) can also be applied to the vertical printing apparatus 500.

FIG. 16 is a diagram illustrating another configuration example of the printing apparatus 500.
In the configuration example shown in FIG. 16, one or more other can stop points are provided between the image forming stop point and the light irradiation stop point. In the configuration example described above, five mobile units 550 are mainly displayed. However, in FIG. 16, more than five mobile units 550 are displayed.

Also in this configuration example shown in FIG. 16, the can body 10 is sequentially conveyed, and the can body 10 is temporarily stopped every time the can body 10 reaches each of a plurality of predetermined can body stop positions.
Specifically, the movement of the can body 10 is stopped every time the can body 10 reaches each of the inkjet heads 11 and every time the can body 10 reaches another stop point other than the ink jet head 11.
More specifically, each time the can body 10 reaches each of the image forming stop portions (hereinafter referred to as “image forming stop portions 16A”) indicated by reference numeral 16A, the can body 10 is stopped. In each of the first curved portion 571, the second curved portion 573, and the second linear portion 574, the can body 10 is stopped at a predetermined stop position.

Furthermore, in the present embodiment, the can body 10 is stopped at the light irradiation stop portion 16B downstream of the image forming stop portion 16A in the conveyance direction of the can body 10. In other words, the can 10 is stopped in the drying unit 530 that performs irradiation with ultraviolet rays.
Here, although not described above, the drying unit 530 is provided with a light source (not shown) that emits ultraviolet rays and a light source storage box 531 that stores the light source. The light source storage box 531 is provided with an inlet portion 531A and an outlet portion 531B, and the can 10 (the moving unit 550) enters the light source storage box 531 through the inlet portion 531A. Further, the can body 10 goes out of the light source storage box 531 through the outlet portion 531B.

Here, in this configuration example, image formation and light irradiation are not performed between the image forming stop point 16A (the image forming stop point 16A located on the most downstream side) and the light irradiation stop point 16B. A can stop portion 16 </ b> C is provided, which makes it difficult for ultraviolet rays to reach the inkjet head 11.

In the present embodiment, the drying unit 530 irradiates ultraviolet rays. For example, when the ultraviolet rays reach the inkjet head 11 located on the upstream side, the ink is cured in the inkjet head 11 and ink clogging occurs. There is a risk that the quality of the formed image may be lowered.

Therefore, in this embodiment, one can stop portion 16C is provided between the image forming stop portion 16A and the light irradiation stop portion 16B, and the distance between the drying unit 530 and the inkjet head 11 is increased. In addition, the ultraviolet rays reaching the inkjet head 11 are reduced.
In the present embodiment, one can stop portion 16C is provided between the image forming stop portion 16A and the light irradiation stop portion 16B. However, two or more can stop portions 16C may be provided. Good.

In addition, in the configuration example shown in FIG. 16, as shown by reference numeral 16 </ b> X, an upstream regulation wall 31 and a downstream regulation wall 32 are provided beside each can body 10 (each mandrel 70).
The upstream regulation wall 31 is located upstream of the can body 10 in the movement direction of the movement unit 550, and the downstream regulation wall 32 is located downstream of the can body 10 in the movement direction of the movement unit 550. To do.

Further, the upstream regulation wall 31 and the downstream regulation wall 32 are arranged along the axial direction of the can body 10 and arranged along the vertical direction.
Further, a plurality (a plurality of sets) of the upstream regulation wall 31 and the downstream regulation wall 32 are provided so as to correspond to each of the plurality of movement units 550 (can body 10), and each of the movement units 550 is further provided with each. Move with it.

The upstream regulating wall 31 is positioned on the upstream side (the side where the inkjet head 11 is provided) from the can body 10 when the can body 10 is stopped at the light irradiation stop point 16B (drying unit 530). To do. As a result, the upstream side regulation wall 31 is positioned between the can 10 and the inkjet head 11, and ultraviolet rays are prevented from going to the inkjet head 11.
Further, when the can body 10 is stopped at the light irradiation stop portion 16 </ b> B (drying unit 530), the downstream side regulation wall 32 is located on the downstream side of the can body 10. Thereby, it is suppressed that an ultraviolet-ray goes to a downstream direction rather than the can 10.

FIG. 17 is a view when the drying unit 530 is viewed from the direction of the arrow XVII in FIG. 16.
As shown in FIG. 17, the drying unit 530 is provided with a light source storage box 531. The light source storage box 531 is provided with the inlet portion 531A as described above.
Here, in this configuration example, when the can body 10 stops inside the light source housing box 531, the upstream side regulation wall 31 provided corresponding to the can body 10 causes the inlet portion 531A of the light source housing box 531 to pass. Block it. Thereby, it is suppressed that an ultraviolet-ray goes to the inkjet head 11 through the entrance part 531A.
As shown in FIG. 16, the downstream regulation wall 32 also closes the outlet portion 531 </ b> B of the light source housing box 531 when the can 10 is stopped inside the light source housing box 531. Thereby, it is suppressed that an ultraviolet-ray leaks from the exit part 531B of the light source storage box 531. FIG.

In the configuration example shown in FIG. 16, a can inspection unit 591 and a can discharge unit 592 are provided between the can input unit 510 (see FIG. 16) and the printing unit 520.
The can inspection unit 591 inspects the can 10 before the printing unit 520 performs image formation on the can 10.
The can body discharge unit 592 discharges the can body 10 determined by the can body inspection unit 591 that the predetermined condition is not satisfied. Specifically, the compressed air is supplied into the mandrel 70 and the can 10 is discharged as in the process in the can discharge unit 540.

FIG. 18 is a diagram showing the configuration of the can inspection unit 591.
A can inspection unit 591 shown in FIG. 18 performs an inspection to determine whether or not the can 10 is deformed.
Specifically, a laser beam that travels along the outer peripheral surface of the can body 10 and along the axial direction of the can body 10 is emitted to the can body inspection portion 591 on one end side of the can body 10. A light source 92A is provided. Furthermore, a light receiving portion 92B that receives the laser light from the light source 92A is provided on the other end side of the can 10.

When a part of the can 10 is deformed as indicated by reference numeral 3A, the laser beam is blocked, and the light receiving unit 92B does not receive the laser beam. Thereby, the deformation of the can 10 is detected.
In addition, the can inspection unit 591 is provided with a reflective laser detection device 92C including both a light source that emits laser light and a light receiving unit that receives the laser light. The reflective laser detection device 92C emits laser light from the light source toward the bottom of the can. The emitted laser light is reflected by the bottom of the can, and the reflected laser light is received by the light receiving unit.

The reflective laser detection device 92C detects the distance from the emission to the light reception to the can bottom, and thereby detects whether the can 10 is completely attached to the mandrel 70. In addition, the presence or absence of the can 10 can also be detected by providing the mandrel 70 with a groove.
In this configuration example, when the can body inspection unit 591 determines that the can body 10 does not satisfy the predetermined condition (when it is determined that the can body 10 is deformed), When it is determined that the mounting state of the can body 10 on the mandrel 70 is incomplete, the can body discharging portion 592 discharges the can body 10.

FIG. 19 is a view showing another configuration example of the mandrel 70.
In the mandrel 70 shown in FIG. 19, the diameter of the one end 237 is smaller than the diameter of the other end 238.
More specifically, in this configuration example, when the mandrel 70 is inserted into the can 10, the one end 237 comes to the top, but the diameter on the one end 237 side is the diameter on the other end 238 side. Is smaller than More specifically, in the present embodiment, the outer peripheral surface of the mandrel 70 and the one end 237 are tapered so that the outer diameter of the mandrel 70 decreases from the other end 238 side toward the one end 237 side. Yes.

Here, if the diameter on the one end 237 side is smaller than the diameter on the other end 238 side as in the present embodiment, wear of the mandrel 70 is suppressed.
More specifically, when the mandrel 70 is inserted into the can body 10, the tip of the mandrel 70 becomes difficult to contact the can body 10, and wear of the mandrel 70 is suppressed.

In this configuration example, as a result of the diameter on the one end 237 side being small, a gap is formed between the outer peripheral surface of the one end 237 and the inner peripheral surface of the can body 10. In the present embodiment, even if there is such a gap, printing is performed by an ink jet method (printing is executed by making the ink droplets adhere to the can body 10, and during the printing, the can body 10 is printed. Therefore, the can 10 is not deformed by printing, and image formation on the can 10 can be performed.
Here, in the printing plate method in which an image is transferred by pressing a plate against the outer peripheral surface of the can body 10 instead of the ink jet method, the can body 10 is recessed inward at a portion where a gap is formed. Will be deformed.

In addition, in the above description, the rotational speed of the can body 10 is not particularly mentioned, but the rotational speed of the can body 10 may be controlled.
Specifically, for example, the movement of the can body 10 from one inkjet head 11 of the two inkjet heads 11 adjacent to each other in the movement direction of the can body 10 to the other inkjet head 11 is started. You may make it control rotation of the can 10 so that the rotation speed of the can 10 until the can 10 reaches the inkjet head 11 may become an integer.

A specific description will be given with reference to FIG. 20 (a schematic view when two adjacent inkjet heads 11 are viewed).
In the process shown in FIG. 20, the can 10 is constantly rotating, and from one inkjet head 11 located on the upstream side (the inkjet head on the right side in the figure, hereinafter referred to as “upstream inkjet head 11 </ b> A”), When the can body 10 moves to the other ink jet head 11 located on the downstream side (the left ink jet head 11 in the figure, hereinafter referred to as “downstream ink jet head 11B”), the can body 10 moves while rotating.

In this process, the number of rotations of the can body 10 from the start of the movement of the can body 10 from the upstream inkjet head 11A to the arrival of the can body 10 at the downstream inkjet head 11B is an integer. It has become.
Thereby, in this embodiment, when the adhesion start position P1 to which the ink ejected from the upstream inkjet head 11A first adhered reaches the downstream inkjet head 11B, the downstream inkjet head 11B is opposed to the downstream side inkjet head 11B. Located in position.

Here, in the upstream inkjet head 11A, a belt-like shape extending from an adhesion start position P1 (position indicated by reference numeral 3A) to which ink first adheres to an adhesion end position P2 (also indicated by reference numeral 3A) to which ink finally adheres. Is formed on the outer peripheral surface of the can 10.
In this embodiment, when the can body 10 moves while rotating and the can body 10 reaches the lower side of the downstream inkjet head 11B, the adhesion start position is located at a position opposite to the lower surface 241 of the downstream inkjet head 11B. P1 is located.

In this embodiment, the can 10 reaches the lower side of the downstream inkjet head 11B, and at the same time, ink is ejected to form an image.
More specifically, in the present embodiment, when the upstream inkjet head 11A completes image formation (the can body 10 rotates once and the adhesion start position P1 again faces the upstream inkjet head 11A). At the same time, the movement of the can 10 is started.
As soon as the can 10 reaches the lower side of the downstream ink jet head 11B (at the same time as the adhesion start position P1 faces the downstream ink jet head 11B), the ink discharge from the downstream ink jet head 11B is started. Then, image formation is started.

Here, in this process, when image formation is started in the downstream inkjet head 11B, the adhesion start position P1 is located immediately below the downstream inkjet head 11B.
Thereby, in this embodiment, the image formation start position when image formation is started by the upstream inkjet head 11A and the image formation start position when image formation is started by the downstream inkjet head 11B coincide. .

Here, when the can 10 reaches the downstream inkjet head 11B, if the adhesion start position P1 is not facing the downstream inkjet head 11B, the adhesion start position P1 is directed to the downstream inkjet head 11B. Control is required.
Specifically, for example, a process such as detecting the state of the can 10 with a rotary encoder and rotating the can 10 based on the detection result is required. On the other hand, in the present embodiment, such processing is unnecessary, and the image formation start positions can be more easily aligned.
Note that the number of rotations of the can body 10 from the start of the movement of the can body 10 from the upstream ink jet head 11A to the arrival of the can body 10 at the downstream ink jet head 11B can be any integer. Or 1 or 2 or more.

As another process, when the can body 10 moves from one inkjet head 11 of the two adjacent inkjet heads 11 to the other inkjet head 11, a predetermined rotation speed (rotation during image formation) is performed. The can 10 may be rotated at a rotational speed greater than (number).
More specifically, when each of the inkjet heads 11 forms an image on the can body 10, the can body 10 is rotated at a predetermined number of revolutions and the can body 10 is moved. (While moving the can body 10), the can body 10 may be rotated at a rotational speed greater than the predetermined rotational speed.

Here, when the rotational speed is increased in this way, the ink on the outer peripheral surface of the can 10 is easily cured. More specifically, in the case of using, for example, thermosetting ink instead of ultraviolet curable ink as in the present embodiment, if the rotation speed increases, the ink becomes easier to dry and the rotation speed does not increase. Compared to the ink, the ink is cured more rapidly.
In addition, the case where ultraviolet curable ink is used has been described above, but thermosetting ink can also be used. In this case, if the rotational speed of the can 10 is increased, the rotational speed is increased. The ink hardens more quickly than when not.

As another process, when the can 10 moves from one inkjet head 11 to the other inkjet head 11 of the two inkjet heads 11 adjacent to each other, the rotational speed is smaller than a predetermined rotational speed. The can body 10 may be rotated.
More specifically, when an image is formed on the can body 10 in each of the inkjet heads 11, when the can body 10 is rotated at a predetermined number of rotations and the can body 10 is moved ( While the can body 10 is being moved), the can body 10 may be rotated at a rotational speed smaller than the predetermined rotational speed.
Thus, when reducing the rotation speed of the can body 10, the total rotation speed of each mechanism part for rotating the can body 10 decreases, and the rotation speed of each mechanism section is constant or as described above. As compared with the case where the size is increased, wear of each mechanism portion is suppressed.

In each ink jet head 11, image formation is not started at the same time as the can body 10 reaches the ink jet head 11, but after the can body 10 rotates a predetermined number of times below the ink jet head 11. The image formation on the can 10 may be started.

Immediately after the can body 10 is moved below each inkjet head 11, the can body 10 may vibrate without being completely stopped. In particular, when the moving speed of the can body 10 is high, the vibration of the can body 10 tends to increase. When the can body 10 vibrates, the quality of the image formed on the can body 10 is likely to deteriorate.
On the other hand, when image formation by the inkjet head 11 is started after rotating the can body 10 below the inkjet head 11 (when image formation by the inkjet head 11 is started after a certain time has elapsed), the can body 10 is reduced or eliminated, and deterioration of the quality of the image formed on the can 10 is suppressed.

In addition, while the can body 10 reaches below the inkjet head 11 and rotates the can body 10 for a certain time, the rotation of the can body 10 is stopped or the rotation speed of the can body 10 is reduced. Also good. However, in this case, when the image formation by the inkjet head 11 is started, it is necessary to accelerate the can 10 that has been stopped or decelerated to the rotational speed necessary for the image formation. May occur.

As another control, the image formation start position (position in the circumferential direction of the can body 10) when the inkjet head 11 starts image formation is made different for each inkjet head 11, and the image formation start position of each color is The circumferential direction of the can 10 may be shifted.
When aligning the image formation start positions, there is a possibility that a portion where the image quality is likely to deteriorate is concentrated in one place and the image quality is deteriorated. More specifically, at the image formation start position, the start point and the end point of the formed image overlap each other, or a gap is formed between the start point and the end point, so that the image quality is likely to deteriorate. In such a case, if the image formation start positions are aligned, the image quality is more likely to deteriorate than when the image formation start positions are not aligned.

If the image formation start position is made different for each inkjet head 11 and the image formation start position for each color is shifted in the circumferential direction of the can 10, deterioration in image quality can be suppressed.
The method for shifting the image formation start position by the inkjet head 11 is not particularly limited, but for example, the image formation start position is shifted by shifting the ink discharge timing by each inkjet head 11.

DESCRIPTION OF SYMBOLS 10 ... Can body, 11 ... Inkjet head, 21 ... Belt member, 22 ... Drive roll, 23 ... Belt motor, 70 ... Mandrel, 71 ... Mandrel side gear, 89 ... Advance / retract mechanism, 90 ... Unit side magnet, 500 ... Printing Apparatus, 520 ... Printing unit, 550 ... Moving unit, 560 ... Moving mechanism, 562 ... Electromagnet, 600 ... Control unit

Claims (14)

1. A moving body that moves while supporting the can body;
   A printing unit that includes a plurality of image forming units, and that performs printing on the can supported by the moving body;
   Moving means for moving the moving body so that the moving body passes through each of the plurality of image forming units and moving the moving body using a linear mechanism;
   A printing apparatus comprising:
2. The printing apparatus according to claim 1, wherein in the printing unit, the moving body moves linearly.
3. The printing apparatus according to claim 1 or 2, wherein the can body is supported so that an axial direction of the can body supported by the moving body intersects a moving direction of the moving body.
4. The moving body moves along an annular path,
   The printing apparatus according to any one of claims 1 to 3, wherein the can body supported by the moving body is disposed in a state of being moved to the outside rather than the inside in the radial direction of the annular path.
5. The printing apparatus according to any one of claims 1 to 4, wherein the moving body is configured to support a plurality of cans.
6. The moving means moves the moving body using a linear mechanism when moving the moving body via each of the plurality of image forming sections, and is provided with the plurality of image forming sections. The printing apparatus according to claim 1, wherein the moving body is moved at a place other than the place without using a linear mechanism.
7. A drive source for rotating the can supported by the movable body;
   The printing apparatus according to claim 1, wherein the drive source is installed at a place other than the moving body.
8. A drive mechanism that rotates the can body, and moves while supporting the can body;
   A printing unit that performs printing on the can supported by the movable body;
   A driving source that is provided at a location different from the moving body and generates a driving force used by the driving mechanism of the moving body;
   A printing apparatus comprising:
9. The printing apparatus according to claim 8, further comprising a transmission mechanism that transmits a driving force generated by the driving source to the driving mechanism of the movable body.
10. A plurality of the moving bodies are provided,
    The printing apparatus according to claim 9, wherein the transmission mechanism is in contact with the driving mechanism provided in each of the plurality of moving bodies and transmits a driving force to the plurality of driving mechanisms.
11. The printing apparatus according to claim 10, wherein the transmission mechanism transmits a driving force to the plurality of driving mechanisms using a belt member that circulates and moves.
12. The transmission mechanism is in contact with the driving mechanism of the movable body and transmits a driving force to the driving mechanism,
    12. The printing apparatus according to claim 9, further comprising a support member that supports the drive mechanism from the side opposite to the installation side of the transmission mechanism across the drive mechanism of the moving body.
13. The printing apparatus according to any one of claims 9 to 12, further comprising advance / retreat means for advancing / retreating the transmission mechanism with respect to the drive mechanism of the moving body.
14. The moving body is provided with a permanent magnet,
    An electromagnet is provided in the moving path of the moving body,
    The printing apparatus according to claim 8, further comprising a moving unit that controls energization of the electromagnet to move the moving body.

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