Printer

Abstract

To increase the efficiency of printing onto a beverage container.SOLUTION: After installing a beverage can 10 on a movable body 230 still in an input part 201, the movable body 230 moves in a direction of downstream movement. When the movable body 230 moves in the direction of downstream movement, the movable body 230 passes through an image hardening part 220 to direct to a printing part 210. Upon a movement of the movable body 230 in the direction of downstream movement, a rolling mechanism 250 provided in the movable body 230 actuates, and thus the beverage can 10 rolls circumferentially. The printing part 210, when the movable body 230 reaches below oneself, prints the outer peripheral surface 11M of the beverage can 10 passing below oneself while rolling circumferentially on support by this movable body 230.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a printing device. [Background technology]

[0002] Patent Document 1 discloses a configuration including a turret head and a fixed station, where the fixed station holds a container and performs printing on the container with a digital print head. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Special Publication No. 2010-522651 Summary of the Invention [Problem to be solved by the invention]

[0004] BACKGROUND ART When manufacturing beverage containers, printing is generally performed on the containers in order to impart a design to the containers and to protect the surfaces of the containers. When printing on a container, if the container is stopped in the printing unit while printing on this container, the efficiency of printing decreases by the time the container is stopped. SUMMARY OF THE INVENTION An object of the present invention is to increase the efficiency of printing on beverage containers. [Means for solving the problem]

[0005] The printing device to which the present invention is applicable is a moving body that supports and moves a cylindrical beverage container, and is equipped with a rotation mechanism that rotates the container in a circumferential direction, so that one end side of the container in the axial direction leads the container as it moves, and a printing unit that prints on the outer surface of the container that is supported by the moving body and moves while rotating in a circumferential direction.

[0006] Here, the container has a tapered section in which the outer diameter decreases as it progresses in the axial direction of the container, and the tapered section has a large outer diameter portion and a small outer diameter portion that are located at different positions in the axial direction of the container, and the printing conditions when the printing unit prints on the large outer diameter portion may be different from the printing conditions when the printing unit prints on the small outer diameter portion. In addition, the printing unit may use an inkjet head to print on the outer surface of the container, and the frequency with which the printing unit ejects ink onto the large outer diameter portion may be greater than the frequency with which the printing unit ejects ink onto the small outer diameter portion. In addition, the printing unit may use an inkjet head to form a dot image on the outer peripheral surface of the container and print on the outer peripheral surface, and the number of rotations of the container from the start of formation of the dot image on the large outer diameter portion to the end of formation of the dot image may be greater than the number of rotations of the container from the start of formation of the dot image on the small outer diameter portion to the end of formation of the dot image. In addition, the printing unit may use an inkjet head to print on the outer surface of the container, and the rotation speed of the container when the printing unit ejects ink onto the large outer diameter portion may be slower than the rotation speed of the container when the printing unit ejects ink onto the small outer diameter portion. In addition, the printing unit may use an inkjet head to form a dot image on the outer peripheral surface of the container and print on the outer peripheral surface, so that the dot image formed by the printing unit on the large outer diameter portion is larger than the dot image formed by the printing unit on the small outer diameter portion. In addition, as the container moves in one direction, with the one end side in the axial direction of the container leading the way, the printing unit prints on the outer surface of the container, and after the printing unit has printed on the outer surface, the moving body moves in the direction opposite to the one direction, causing the container to move in the opposite direction. In addition, a curing means for curing the image formed on the outer surface of the container by the printing unit may be provided at a location different from the location where the printing unit is installed in the movement direction of the moving body. In addition, the container may have a tapered section whose outer diameter becomes smaller as it progresses in the axial direction of the container, and when the container is moved by the moving body, the container may move with its axis tilted relative to the horizontal direction. In addition, the reduced diameter portion may be provided with a large outer diameter portion and a small outer diameter portion that are located at different axial positions of the container, and when the container is moved by the moving body, the radial center of the small outer diameter portion may be positioned higher than the radial center of the large outer diameter portion. In addition, the reduced diameter portion of the container may be configured to reduce in diameter at a constant rate as it progresses in the axial direction of the container, and when printing on the container is performed by the printing unit, the portion of the outer surface of the reduced diameter portion that faces the printing unit may be positioned in a horizontal direction. The moving body may further be provided with a change mechanism for changing the inclination of the container relative to the horizontal direction. The printing unit may also be provided with a plurality of inkjet heads that eject different colors, and printing may be performed on the outer peripheral surface by adhering ink from the plurality of inkjet heads to the outer peripheral surface. The inkjet heads may be arranged so that their positions in the moving direction of the moving body are shifted from one another. Furthermore, the container may be placed on the moving body at an input section where the container is inserted into the printing device, and after the container is placed on the moving body, the moving body may move toward the printing section along a predetermined movement path, and after the printing section prints on the container, the moving body, while supporting the container, may return to the input section along the movement path that it took when moving from the input section toward the printing section. [Effects of the Invention]

[0007] According to the present invention, the efficiency of printing on beverage containers can be improved. [Brief explanation of the drawings]

[0008] [Figure 1] 1A and 1B are diagrams illustrating a beverage can. [Figure 2] FIG. 1 is a diagram showing a printing device that prints on beverage cans. [Figure 3] FIG. 2 is a diagram illustrating an example of the hardware configuration of a control unit. [Figure 4] 1(A) and 1(B) are diagrams illustrating a support member that supports a beverage can. [Figure 5] (A) and (B) are diagrams showing details of the moving body. [Figure 6] 10A and 10B are diagrams showing images formed on a beverage can when the frequency of ink ejection onto the large outer diameter portion is set higher than the frequency of ink ejection onto the small outer diameter portion; [Figure 7] 10A and 10B are diagrams showing other configuration examples of beverage cans. [Figure 8] 8 is a diagram showing a printing device that prints on the beverage can shown in FIG. 7. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings. Figures 1(A) and (B) are diagrams illustrating a beverage can 10 according to this embodiment. Figure 1(A) is a front view of the beverage can 10, and Figure 1(B) is a view of the beverage can 10 as viewed from the direction of arrow IB in Figure 1(A). This beverage can 10, which is an example of a container, is formed in a cylindrical shape. More specifically, this beverage can 10 is formed in a cylindrical shape. Furthermore, as shown in FIG. 1(A), the beverage can 10 is provided with a tapered portion 11 whose outer diameter decreases in the axial direction.

[0010] In this embodiment, a reduced diameter portion 11 is provided in the beverage can 10, and the beverage can 10 of this embodiment is a so-called tapered can. The beverage can 10 is provided with a can body 31, and in this embodiment, the entire can body 31 is tapered. As shown in FIG. 1(A), a beverage can 10 has one end 11A and another end 11B that are located at different axial positions. A circular opening 11E is provided at one end 11A of beverage can 10. A bottom 11F is provided at the other end 11B of beverage can 10. Can body 31 is located between opening 11E and bottom 11F.

[0011] In this embodiment, the outer diameter of one end 11A of the beverage can 10 is larger than the outer diameter of the other end 11B of the beverage can 10. The reduced diameter portion 11 is provided on the beverage can 10 from the one end 11A side to the other end 11B side. The reduced diameter portion 11 is provided so that the outer diameter gradually decreases as it progresses in the axial direction of the beverage can 10. More specifically, the reduced diameter portion 11 is provided so that the outer diameter gradually decreases as it progresses from one end 11A of the beverage can 10 to the other end 11B.

[0012] The reduced diameter portion 11 has a large outer diameter portion 11X, which is a portion with a large outer diameter, and a small outer diameter portion 11Y, which is a portion with a small outer diameter. In this embodiment, when comparing positions in the axial direction of the beverage can 10, the position of the large outer diameter portion 11X and the position of the small outer diameter portion 11Y are different. Furthermore, the reduced diameter portion 11 has an intermediate portion 11Z between the large outer diameter portion 11X and the small outer diameter portion 11Y. In this embodiment, when comparing the outer diameter of the large outer diameter portion 11X, the outer diameter of the intermediate portion 11Z, and the outer diameter of the small outer diameter portion 11Y, the relationship among the outer diameters is as follows. Relationship of outer diameter: outer diameter of large outer diameter part 11X > outer diameter of intermediate part 11Z > outer diameter of small outer diameter part 11Y

[0013] 1(A), an image 101 is formed on the outer peripheral surface 11M of the beverage can 10. This image 101 is composed of a plurality of dot images 102 formed by curing ink ejected by an inkjet head, which will be described later. The drawings indicated by the reference numerals 1A, 1B, and 1C in FIG. 1(A) are enlarged views of parts of an image 101 formed on an outer peripheral surface 11M of a beverage can 10. In this embodiment, as shown in the figures indicated by symbols 1A, 1B, and 1C, a dot image 102 is formed on the outer peripheral surface 11M of the reduced diameter portion 11, and an image 101 is formed by a plurality of these dot images 102.

[0014] The dot images 102 are arranged in the axial direction of the beverage can 10. The dot images 102 are also arranged in the circumferential direction of the beverage can 10. The figures indicated by symbols 1A, 1B, and 1C in Figure 1(A) show dot images 102 arranged in the axial direction of the beverage can 10, and show one row of dot images 102 along this axial direction. In this embodiment, as shown in the figures indicated by symbols 1A and 1C, the size of the dot image 102 formed in the large outer diameter portion 11X of the narrowing portion 11 is larger than the size of the dot image 102 formed in the small outer diameter portion 11Y of the narrowing portion 11. In other words, in this embodiment, the diameter of the dot image 102 formed on the large outer diameter portion 11X of the reduced diameter portion 11 is larger than the diameter of the dot image 102 formed on the small outer diameter portion 11Y of the reduced diameter portion 11.

[0015] In the printing device of this embodiment (described later), when forming a dot image 102 using an inkjet head, the dot image 102 is formed so that the size of the dot image 102 formed in the large outer diameter portion 11X is larger than the size of the dot image 102 formed in the small outer diameter portion 11Y. In this embodiment, two types of dot images 102, large dot images 102 and small dot images 102, are formed.

[0016] In this embodiment, as shown by the symbol 1B in Figure 1(A), the dot image 102 is formed so that a large dot image 102 is formed in the large outer diameter region 11J, which is the region located closer to the large outer diameter portion 11X than the intermediate portion 11Z, with the intermediate portion 11Z as the boundary. In this embodiment, the dot images 102 are formed so that small dot images 102 are formed in the small outer diameter region 11K, which is a region located closer to the small outer diameter portion 11Y than the intermediate portion 11Z.

[0017] In this embodiment, two types of dot images 102 are formed in this way: large dot images 102 and small dot images 102. However, the present invention is not limited to this, and the types of dot images 102 with different sizes may be three or more. When the dot images 102 are of a plurality of different sizes, the sizes of the dot images 102 are changed in order from the small outer diameter portion 11Y to the large outer diameter portion 11X, and the dot images 102 become larger each time the size changes. Alternatively, the dot images 102 may be formed so that they become gradually larger from the small outer diameter portion 11Y toward the large outer diameter portion 11X.

[0018] In this embodiment, the beverage content is filled into the beverage can 10 through an opening 11E located at one end 11A of the beverage can 10. A can lid (not shown) is then attached to the opening 11E to close the opening 11E. This completes the beverage can filled with the beverage. Examples of beverages that can be filled include alcoholic beverages such as beer, and non-alcoholic beverages such as soft drinks. In this embodiment, the beverage can 10 refers to an empty can body before being filled with a beverage. It should be noted that a can lid is not essential, and in some cases, after a beverage is poured into the beverage can 10, a can lid is not attached, and the beverage inside the beverage can 10 may be consumed by a user without the can lid.

[0019] The beverage can 10 of this embodiment is an example of a container. More specifically, the beverage can 10 of this embodiment is an example of a beverage container. The beverage can 10 of this embodiment is made of metal and is formed from a metal material. Specifically, the beverage can 10 is formed from, for example, aluminum, an aluminum alloy, or the like. The beverage can 10 is formed, for example, by subjecting a flat plate material (substrate) to draw and ironing (DI) forming or stretch draw forming.

[0020] The material of the beverage can 10 is not particularly limited, and the beverage can 10 may be made of a resin material or paper. In other words, a container having a reduced diameter portion 11, such as the beverage can 10 of this embodiment, may be made of a resin material or paper. Furthermore, the method for forming the container is not limited, and the container may be formed by a method other than the above-mentioned draw and ironing (DI) forming or stretch draw forming.

[0021] FIG. 2 is a diagram showing a printing device 100 that prints on a beverage can 10. As shown in FIG. In this embodiment, an image 101 (see FIG. 1(A)) is formed on the outer peripheral surface 11M of the beverage can 10 by the printing device 100 shown in FIG. This printing device 100 is provided with an insertion section 201 into which a beverage can 10 is inserted, a printing section 210 that prints on the outer peripheral surface 11M of the beverage can 10 to form an image 101 on this outer peripheral surface 11M, and an image hardening section 220 that hardens the image 101 formed by the printing section 210. Furthermore, the printing device 100 is provided with a control unit 60 that controls each unit of the printing device 100 .

[0022] 3 is a diagram showing an example of the hardware configuration of the control unit 60. The control unit 60 is realized by a computer. The control unit 60 has an arithmetic processing unit 21 that executes digital arithmetic processing according to a program, and a secondary storage unit 212 that stores information. The secondary storage unit 212 is realized by an existing information storage device such as an HDD (Hard Disk Drive), semiconductor memory, or magnetic tape.

[0023] The arithmetic processing unit 21 includes a CPU 21a as an example of a processor. The arithmetic processing unit 21 is also provided with a RAM 21b used as a working memory for the CPU 21a, and a ROM 21c in which programs executed by the CPU 21a are stored. The arithmetic processing unit 21 is also provided with a nonvolatile memory 21d that is rewritable and can retain data even if the power supply is interrupted.

[0024] The nonvolatile memory 21d is configured, for example, with a battery-backed SRAM, a flash memory, etc. The secondary storage unit 212 stores files and the like, as well as programs executed by the arithmetic processing unit 21. In this embodiment, the CPU 21a of the arithmetic processing unit 21 reads programs stored in the ROM 21c or the secondary storage unit 212, and thereby various processes performed by the printing device 100 are executed.

[0025] The program executed by the CPU 21a may be provided to the printing device 100 in a state where it is stored in a computer-readable recording medium such as a magnetic recording medium (such as a magnetic tape or a magnetic disk), an optical recording medium (such as an optical disk), a magneto-optical recording medium, or a semiconductor memory. The program executed by the CPU 21a may also be provided to the printing device 100 using a communication means such as the Internet.

[0026] The printing device 100 will be further described with reference to FIG. The printing device 100 is further provided with a moving body 230 that supports and moves the beverage can 10. The printing device 100 is also provided with a moving mechanism 240 that moves the moving body 230. The movement mechanism 240 moves the moving body 230 in one direction indicated by an arrow 2A in the figure, and then in the opposite direction, thereby causing the moving body 230 to move back and forth.

[0027] The moving mechanism 240 is not particularly limited, and an existing known mechanism may be used. The moving mechanism 240 can be composed of, for example, a belt member that moves in a circular motion, a part of which follows the direction of movement of the moving body 230, a rotating member such as a pulley that is arranged in contact with the inner surface of the belt member, and a drive motor that rotates this rotating member. When using this moving mechanism 240, the moving body 230 is fixed to a belt member, and the belt member to which the moving body 230 is fixed is rotated in one direction or the other. This causes the moving body 230 to move. Additionally, the moving mechanism 240 can be configured, for example, by a rack gear to which the moving body 230 is fixed, a pinion gear that meshes with this rack gear, and a drive motor that rotates this pinion gear.

[0028] Furthermore, the moving body 230 is provided with a rotation mechanism 250 that rotates the beverage can 10 in the circumferential direction. In this embodiment, the rotation mechanism 250 rotates the beverage can 10 supported by the moving body 230 in the circumferential direction. The rotation mechanism 250 is provided with a drive motor (not shown), and in this embodiment, the beverage can 10 is rotated by this drive motor.

[0029] In this embodiment, when beverage can 10 is placed on moving body 230, moving body 230 is positioned in insertion section 201. Then, beverage can 10 is placed on moving body 230 which is stopped in insertion section 201. In this embodiment, a support member 260 is provided to support the beverage can 10. In this embodiment, when the beverage can 10 is placed on the moving body 230, the beverage can 10 is supported by the moving body 230 via this support member 260.

[0030] In this embodiment, when placing the beverage can 10 on the moving body 230, the beverage can 10 is placed on the moving body 230 with one end 11A of the beverage can 10 in the axial direction positioned downstream in the direction of movement of the moving body 230. In other words, in this embodiment, beverage can 10 is placed on moving body 230 with other end 11B of beverage can 10 in the axial direction positioned upstream in the direction of movement of moving body 230.

[0031] More specifically, in this embodiment, the beverage can 10 is placed on the moving body 230 with the large outer diameter portion 11X side positioned downstream in the moving direction of the moving body 230. In other words, in this embodiment, the beverage can 10 is placed on the moving body 230 with the small outer diameter portion 11Y of the beverage can 10 positioned upstream in the direction of movement of the moving body 230. In this embodiment, when the moving body 230, which is located in the insertion section 201 and on which the beverage can 10 is placed, moves toward the printing section 210, the beverage can 10 moves with one end 11A of the beverage can 10 leading the way.

[0032] In this embodiment, the large outer diameter portion 11X of the beverage can 10 is at the front, and the beverage can 10 moves with this large outer diameter portion 11X side positioned downstream in the moving direction of the moving body 230. In this embodiment, after the beverage can 10 is placed on the moving body 230, the moving body 230 travels toward the printing unit 210 along a predetermined movement path 100R. In the following, in this specification, the direction of movement of the moving body 230 when it moves from the input section 201 towards the printing section 210 is referred to as the "downstream movement direction," and the direction of movement of the moving body 230 when it returns from the printing section 210 to the input section 201 is referred to as the "upstream movement direction."

[0033] 4(A) and (B) are diagrams illustrating a support member 260 that supports the beverage can 10. In this embodiment, the beverage can 10 is placed on the moving body 230 via a support member 260. In this embodiment, when placing beverage can 10 on movable body 230, first, as shown in Figures 4(A) and (B), a worker attaches support member 260 to beverage can 10. In this embodiment, beverage can 10, which is supported by support member 260 (see Figure 4(B)), is placed on movable body 230 (not shown in Figure 4).

[0034] As shown in FIG. 4(A), the support member 260 is composed of an inner member 261 and an outer member 262. The inner member 261 has an insertion part 261A having a truncated cone shape and to be inserted into the beverage can 10, and an inner rotation shaft 261B fixed to the insertion part 261A. The insertion part 261A and the inner rotation shaft 261B are arranged coaxially. A magnet 261C is provided at the tip of the insertion portion 261A. Furthermore, a receiving gear 261D, which is a gear for receiving a driving force, is attached to the inner rotating shaft 261B.

[0035] The outer member 262 includes a facing portion 262A formed in a disk shape and arranged to face the bottom portion 11F of the beverage can 10, and an outer rotation shaft 262B fixed to the facing portion 262A. The facing portion 262A and the outer rotating shaft 262B are arranged coaxially. A magnet 262C is provided at the tip of the facing portion 262A.

[0036] When the beverage can 10 is supported by the support member 260, the insertion portion 261A of the inner member 261 is inserted into the beverage can 10 as shown by the arrow 4B in FIG. 4(A). Furthermore, as shown by arrow 4C, the opposing portion 262A of the outer member 262 is disposed at a position opposing the bottom portion 11F of the beverage can 10. As a result, in this embodiment, the insertion portion 261A and the facing portion 262A attract each other, and as shown in FIG. 4(B), the bottom 11F of the beverage can 10 is sandwiched between the insertion portion 261A and the facing portion 262A. As shown in FIG. 1(A), the bottom 11F of the beverage can 10 is recessed, and the facing portion 262A fits into the recessed bottom 11F.

[0037] In this embodiment, as shown in FIGS. 4(A) and 4(B), a magnet 261C is provided in the insertion portion 261A, and a magnet 262C is provided in the opposing portion 262A. In this case, when the beverage can 10 is supported by the support member 260, the magnets 261C and 262C cause the insertion portion 261A and the opposing portion 262A to attract each other. The bottom 11F of the beverage can 10 is sandwiched between the insertion portion 261A and the opposing portion 262A, which attract each other.

[0038] In this embodiment, the insertion portion 261A of the inner member 261 enters the interior of the beverage can 10, whereby the support member 260 supports the beverage can 10. In this embodiment, the beverage can 10 is supported by the support member 260 by the bottom 11F of the beverage can 10 being sandwiched between the insertion portion 261A and the facing portion 262A which attract each other. As shown in FIG. 4(B), when the beverage can 10 is supported by the support member 260, the outer rotation shaft 262B and the inner rotation shaft 261B are arranged coaxially.

[0039] 5(A) and 5(B) are diagrams showing details of the moving body 230. FIG. Fig. 5(A) is a diagram of moving body 230 viewed from the direction indicated by arrow VA in Fig. 2. Fig. 5(B) is a diagram of moving body 230 viewed from the direction indicated by arrow VB in Fig. 2. Fig. 5(B) also shows the details of rotation mechanism 250.

[0040] As shown in FIG. 5(A), an upstream groove 231B extending in the up-down direction is provided in an upstream portion 231A of the moving body 230, which is a portion located on the upstream side in the downstream movement direction. When the support member 260 and the beverage can 10 are installed on the moving body 230, the outer rotation shaft 262B (see FIG. 4(B)) is inserted into the upstream groove 231B.

[0041] As shown in FIG. 5(B), a downstream groove 231D extending in the up-down direction is also provided in a downstream portion 231C of the moving body 230, which is a portion located downstream in the downstream movement direction. When the support member 260 and the beverage can 10 are installed on the moving body 230, the inner rotating shaft 261B (see FIG. 4(B)) is inserted into the downstream groove 231D.

[0042] 5(B), the above-described rotation mechanism 250 is provided at a position facing the downstream portion 231C outside the moving body 230. The rotation mechanism 250 is provided with a drive gear 251 that is rotated by a drive motor (not shown).

[0043] In this embodiment, the support member 260 and the beverage can 10 are attached to the moving body 230 by inserting the outer rotation shaft 262B into the upstream groove 231B and the inner rotation shaft 261B into the downstream groove 231D. When the inner rotating shaft 261B is inserted into the downstream groove 231D, the receiving gear 261D (see FIG. 4(B)) attached to the inner rotating shaft 261B is placed on the driving gear 251. This connects the receiving gear 261D and the drive gear 251. As a result, when the drive motor of the rotation mechanism 250 rotates, the beverage can 10 rotates in the circumferential direction.

[0044] Although not described above, a regulating member (not shown) is attached to the outer rotating shaft 262B and the inner rotating shaft 261B of the support member 260 (Figure 4(B)) to regulate the movement of the support member 260 in the direction indicated by the arrow 4X, which is the axial direction of the support member 260. This regulating member is made up of, for example, a disk-shaped member that is arranged coaxially with the outer rotation shaft 262B and the inner rotation shaft 261B. In this embodiment, this restricting member abuts against an abutment portion (not shown) provided on the movable body 230. This restricts the movement of the support member 260 relative to the movable body 230, that is, the movement of the support member 260 in the axial direction.

[0045] In the above, the case where the support member 260 (see Figure 4) is composed of two members, the inner member 261 and the outer member 262, has been described, but the support member 260 may also be composed of only one of the inner member 261 and the outer member 262. When the support member 260 is configured, for example, only by the inner side member 261, the inner side member 261 is supported by the moving body 230 in a state in which an inner side rotation shaft 261B provided on the inner side member 261 is rotatable. In this case, the rotation mechanism 250 rotates the inner rotation shaft 261B, and the beverage can 10 rotates in the circumferential direction accordingly.

[0046] Furthermore, for example, when the support member 260 is configured only by the outer member 262, the outer member 262 is provided with, for example, a suction function, and the bottom 11F of the beverage can 10 is supported by the negative pressure generated by this suction function. Furthermore, when the support member 260 is configured only by the external member 262, the external rotating shaft 262B provided on the external member 262 is supported by the moving body 230 in a rotatable state. Furthermore, when the support member 260 is configured only by the outer member 262, for example, the above-mentioned receiving gear 261D (see FIG. 4(B)) is provided on the outer rotating shaft 262B. The driving force from the rotation mechanism 250 is transmitted to the outer rotation shaft 262B via this receiving gear 261D.

[0047] Referring again to FIG. 2, the operation of the printing device 100 will be described. After beverage can 10 is placed on moving body 230, which is stopped at insertion section 201, moving body 230 moves in the downstream movement direction. As described above, when beverage can 10 is placed on moving body 230, beverage can 10 is placed on moving body 230 via support member 260. When the moving body 230 moves in the downstream movement direction, the moving body 230 moves to the right in the figure, passes through the image curing unit 220, and heads toward the printing unit 210.

[0048] When the moving body 230 moves in the downstream movement direction, the rotation mechanism 250 provided on the moving body 230 operates, thereby rotating the beverage can 10 in the circumferential direction. When the moving body 230 reaches below the printing unit 210, the printing unit 210 is supported by the moving body 230 and rotates in the circumferential direction, printing on the outer peripheral surface 11M of the beverage can 10 passing below the printing unit 210.

[0049] The printing unit 210 is provided with a plurality of inkjet heads 19 that eject ink in different colors. In this embodiment, printing is performed on the outer peripheral surface 11M of the beverage can 10 by depositing ink from the multiple inkjet heads 19 onto the outer peripheral surface 11M. As a result, the image 101 shown in Fig. 1(A) is formed on the outer peripheral surface 11M. The inkjet heads 19 are arranged side by side in the left-right direction in the drawing, which is the direction of movement of the movable body 230. The inkjet heads 19 are provided so that their positions in the direction of movement of the movable body 230 are shifted from one another.

[0050] In this embodiment, the inkjet heads 19 include a first inkjet head 19C that ejects cyan ink, a second inkjet head 19M that ejects magenta ink, a third inkjet head 19Y that ejects yellow ink, and a fourth inkjet head 19K that ejects black ink. In this embodiment, the first inkjet head 19C to the fourth inkjet head 19K form the image 101 on the outer peripheral surface 11M of the beverage can 10 using ultraviolet curable ink.

[0051] The printing unit 210 uses an inkjet printing method to form an image 101 on a beverage can 10 that has been moved from the upstream side. Formation of image 101 by inkjet printing refers to printing onto beverage can 10 by ejecting ink from inkjet head 19. When ink is ejected from inkjet head 19 and adhered to beverage can 10, a plurality of dot images 102 (see FIG. 1(A)) are formed on outer peripheral surface 11M of beverage can 10. In this embodiment, the plurality of dot images 102 form image 101 shown in FIG. 1(A).

[0052] Note that the dot image 102 shown in FIG. 1(A) and the dot image 102 described below both indicate the dot image 102 formed by one of the four inkjet heads 19 provided for each color. More specifically, the dot image 102 shown in FIG. 1(A) and the dot images 102 described below each represent a dot image 102 formed by one inkjet head 19 corresponding to one color, such as an inkjet head 19 corresponding to black. Of the four inkjet heads 19, the remaining three inkjet heads 19 each form a dot image 102 in the same manner as the dot image 102 formed by the one inkjet head 19 described above.

[0053] A plurality of ejection ports (not shown) for ejecting ink are provided on the bottom surface of the inkjet head 19, and in this embodiment, an image 101 is formed by ejecting ink from the plurality of ejection ports. A known method can be used to form the image 101 by inkjet printing, such as a piezo method, a thermal (bubble) method, or a continuous method.

[0054] In this embodiment, as shown in Figure 2, beverage can 10 moves with its axial direction tilted relative to the horizontal. When moving body 230 moves, beverage can 10 moves with its axis 10G tilted relative to the horizontal. In this embodiment, when the beverage can 10 moves, the small outer diameter center portion 54, which is the radial center portion of the small outer diameter portion 11Y, is positioned higher than the large outer diameter center portion 55, which is the radial center portion of the large outer diameter portion 11X.

[0055] Furthermore, in this embodiment, when printing is performed on beverage can 10 by printing unit 210, opposing portion 92 of the outer peripheral surface of reduced diameter portion 11 that faces printing unit 210 is arranged in a horizontal direction. In this embodiment, the reduced diameter portion 11 of the beverage can 10 is provided so that the diameter decreases at a constant rate as it progresses in the axial direction of the beverage can 10. In this embodiment, as shown in FIG. 2, when the moving beverage can 10 is viewed from the side, the portion 11W of the outer surface of the reduced diameter portion 11 that faces the inkjet head 19 extends in the left-right direction in the figure and is linear.

[0056] In this embodiment, ink from the inkjet head 19 adheres to this linear portion of the reduced diameter portion 11. In this embodiment, ink is ejected downward from above onto the outer peripheral surface 11M of the beverage can 10, forming an image 101 (see FIG. 1(A)) on this outer peripheral surface 11M. In this embodiment, a portion of the outer peripheral surface 11M of the beverage can 10 faces upward in the vertical direction. Ink is ejected from above this portion onto this portion.

[0057] In this embodiment, the beverage can 10 moves with the large outer diameter portion 11X at the front, but the manner in which the beverage can 10 moves is not limited to this. The beverage can 10 may also move with the small outer diameter portion 11Y at the front. Even when the beverage can 10 moves with the small outer diameter part 11Y at the forefront, the small outer diameter center part 54, which is the center of the small outer diameter part 11Y, is positioned higher than the large outer diameter center part 55, which is the center of the large outer diameter part 11X. Furthermore, even when the beverage can 10 moves with the small outer diameter portion 11Y leading the way, the opposing portion 92 is aligned horizontally.

[0058] In this embodiment, the beverage can 10, rotating in the circumferential direction, passes in order below the four inkjet heads 19 provided in the printing unit 210. During this passage, ink is ejected onto the outer peripheral surface 11M of the beverage can 10. As a result, an image 101 made up of dot images 102 (see FIG. 1(A)) is formed on the outer peripheral surface 11M of the beverage can 10.

[0059] Thereafter, the moving body 230 returns to the insertion section 201, and accordingly, the beverage can 10 returns to the insertion section 201. As will be described later, when the beverage can 10 returns to the insertion section 201, the image hardening section 220 irradiates the beverage can 10 with light. In this embodiment, after printing on the beverage can 10 by the printing unit 210, the moving body 230 supporting the beverage can 10 returns to the insertion unit 201. When returning to the input unit 201, the moving body 230 returns to the input unit 201 along the movement path 100R that it took when moving from the input unit 201 towards the printing unit 210.

[0060] Here, for example, a mode is also conceivable in which the path along which the moving body 230 moves is formed into a loop, and the moving body 230 moves in a circular manner. In this case, after printing on the beverage can 10 by the printing unit 210, the moving body 230 supporting the beverage can 10 returns to the insertion unit 201 via a path different from the above-mentioned moving path 100R which functions as the outbound path. Forming the moving path along which the moving body 230 moves in a ring shape tends to increase the size of the printing device 100. In contrast, as in this embodiment, if the moving body 230 is configured to return to the input unit 201 via the moving path 100R that functions as the outbound path, the printing device 100 is less likely to increase in size.

[0061] In this embodiment, the printing conditions when the printing unit 210 prints on the large outer diameter portion 11X are different from the printing conditions when the printing unit 210 prints on the small outer diameter portion 11Y. Specifically, in this embodiment, the printing conditions when the printing unit 210 prints on the large outer diameter portion 11X are such that a large dot image 102 is formed. In this embodiment, the printing conditions when the printing unit 210 prints on the small outer diameter portion 11Y are such that small dot images 102 are formed.

[0062] In this embodiment, when the beverage can 10 passes below the printing unit 210, the state where the large outer diameter region 11J faces the inkjet head 19 is switched to the state where the small outer diameter region 11K faces the inkjet head 19. In this embodiment, when the state where the large outer diameter region 11J faces the inkjet head 19 changes to the state where the small outer diameter region 11K faces the inkjet head 19, the amount of ink ejected changes. Specifically, the amount of ink contained in each ink droplet is changed.

[0063] In this embodiment, the beverage can 10 moves in a state in which the large outer diameter region 11J is located downstream of the small outer diameter region 11K in the downstream movement direction. In this case, the beverage can 10 switches from a state in which the large outer diameter region 11J faces the inkjet head 19 to a state in which the small outer diameter region 11K faces the inkjet head 19 during its movement. In this embodiment, when this switching occurs, the amount of ink contained in one ink droplet is changed as described above.

[0064] More specifically, in this embodiment, when this switching occurs, the control unit 60 performs a setting to reduce the amount of ink contained in each ink droplet. The control unit 60 determines whether or not this switching has occurred based on, for example, the drive amount of the drive motor provided in the moving mechanism 240, the detection result of the position of the moving body 230 by a position sensor (not shown), and the like. When this switch occurs and a setting is made to reduce the amount of ink contained in each ink droplet, as described above, in this embodiment, a large dot image 102 is formed in the large outer diameter region 11J and a small dot image 102 is formed in the small outer diameter region 11K.

[0065] Alternatively, a plurality of inkjet heads 19 may be provided, each of which ejects a different amount of ink per droplet for each color. In this case, by switching the inkjet head 19 to be used, a large dot image 102 is formed in the large outer diameter region 11J, and a small dot image 102 is formed in the small outer diameter region 11K. Alternatively, as will be described later, the large dot image 102 and the small dot image 102 may be formed by varying the number of times ink is ejected when forming the large dot image 102 and the number of times ink is ejected when forming the small dot image 102.

[0066] In the case where a reduced diameter section 11 is provided on the beverage can 10 as in this embodiment, if ink is ejected from the inkjet head 19 at regular time intervals, the formed image 101 may have variations in shade, which may result in a deterioration in the quality of the formed image 101. When a beverage can 10 is provided with a reduced diameter portion 11, the spacing between the dot images 102 arranged in a circumferential direction of the large outer diameter portion 11X is greater than the spacing between the dot images 102 arranged in a circumferential direction of the small outer diameter portion 11Y.

[0067] In this case, the formed image 101 may have uneven shading, which may result in a deterioration in the quality of the formed image 101. In contrast to this, in this embodiment, large dot images 102 are formed in the large outer diameter portion 11X of the reduced diameter portion 11. Also, in this embodiment, small dot images 102 are formed in the small outer diameter portion 11Y of the reduced diameter portion 11. In this case, the shading of the image 101 formed on the reduced diameter portion 11 becomes smaller.

[0068] In addition, when the printing conditions when printing on the large outer diameter portion 11X are different from the printing conditions when printing on the small outer diameter portion 11Y, for example, the frequency of ink ejection onto the large outer diameter portion 11X may be made higher than the frequency of ink ejection onto the small outer diameter portion 11Y. FIG. 6 is a diagram showing an image 101 formed on a beverage can 10 when the frequency of ink ejection onto the large outer diameter portion 11X is set higher than the frequency of ink ejection onto the small outer diameter portion 11Y.

[0069] If the frequency of ink ejection onto the large outer diameter portion 11X is made greater than the frequency of ink ejection onto the small outer diameter portion 11Y, then, as shown in Figure 6, the number of dot images 102 located on the large outer diameter portion 11X and arranged in the circumferential direction of the beverage can 10 will be greater than the number of dot images 102 located on the small outer diameter portion 11Y and arranged in the circumferential direction of the beverage can 10. Specifically, in the example shown in Figure 6, the number of large dot images 102 located in the area indicated by reference symbol 5A in Figure 6 and aligned in a line around the circumference of the beverage can 10 is greater than the number of small dot images 102 located in the area indicated by reference symbol 5B in Figure 6 and aligned in a line around the circumference of the beverage can 10. In this embodiment, dot images 102 are formed sequentially on beverage can 10 as it moves and rotates. In this case, the row of dot images 102 arranged in the circumferential direction of beverage can 10 is spiral, but in Figure 6, the row of dot images 102 is shown as being aligned along the circumferential direction. Alternatively, the rows of dot images 102 arranged in the circumferential direction of beverage can 10 may be prevented from forming a spiral. To prevent the rows of dot images 102 arranged in the circumferential direction of beverage can 10 from forming a spiral, it may be possible, although this takes time, to form a predetermined number of rows of dot images 102 in the axial direction by rotating beverage can 10 once while the beverage can 10 is stopped, and then move beverage can 10 by the distance of the formed rows to form the predetermined number of rows of dot images 102 again.

[0070] In this way, by making the number of large dot images 102 formed in the large outer diameter portion 11X greater than the number of small dot images 102 formed in the small outer diameter portion 11Y, it is possible to make the shading of the image 101 even less pronounced than when the numbers of dot images 102 are the same. When forming the dot image 102 in the form shown in Figure 6, as described above, the frequency of ink ejection onto the beverage can 10 when ink is ejected onto the large outer diameter portion 11X is set to be greater than the frequency of ink ejection onto the beverage can 10 when ink is ejected onto the small outer diameter portion 11Y.

[0071] In other words, when forming the dot image 102 in the form shown in Figure 6, the number of times that the inkjet head 19 ejects ink per unit time when printing on the large outer diameter portion 11X is made greater than the number of times that the inkjet head 19 ejects ink per unit time when printing on the small outer diameter portion 11Y. As a result, in this case, the number of large dot images 102 formed in the large outer diameter portion 11X and aligned in the circumferential direction of the beverage can 10 is greater than the number of small dot images 102 formed in the small outer diameter portion 11Y and aligned in the circumferential direction of the beverage can 10.

[0072] Additionally, when forming the dot image 102 in the form shown in Figure 6, the rotation speed of the beverage can 10 when ink is ejected into the large outer diameter portion 11X may be set to be slower than the rotation speed of the beverage can 10 when ink is ejected into the small outer diameter portion 11Y. In this case too, the number of large dot images 102 formed in the large outer diameter portion 11X and arranged in the circumferential direction of the beverage can 10 is greater than the number of small dot images 102 formed in the small outer diameter portion 11Y and arranged in the circumferential direction of the beverage can 10.

[0073] In this way, when the rotation speed of the beverage can 10 is changed depending on the part onto which ink is ejected, ink is ejected one color at a time, rather than simultaneously from the multiple inkjet heads 19. In this case, the moving body 230 is moved back and forth each time ink is ejected from one inkjet head 19. Specifically, in this case, for example, first, ink is ejected onto the beverage can 10 using only the first inkjet head 19C (see FIG. 2). More specifically, in this case, only the first inkjet head 19C is used to form large dot images 102 arranged in the circumferential direction in the large outer diameter region 11J.

[0074] Then, when the small outer diameter region 11K reaches below the first inkjet head 19C, the rotation speed of the beverage can 10 is increased. Then, small dot images 102 arranged in the circumferential direction of the beverage can 10 are formed using the first inkjet head 19C on the small outer diameter region 11K of the beverage can 10 while the rotation speed is increased. As a result, the first inkjet head 19C forms the dot image 102 using the first color ink. Thereafter, the above operation is similarly carried out for each of the remaining three inkjet heads 19.

[0075] Alternatively, the frequency of ink ejection into the large outer diameter region 11J may be set higher than the frequency of ink ejection into the small outer diameter region 11K, and the rotation speed of the beverage can 10 when ink is ejected into the large outer diameter region 11J may be set lower than the rotation speed of the beverage can 10 when ink is ejected into the small outer diameter region 11K. In this case, too, similar to the above, ink is ejected for each color, and the moving body 230 is moved back and forth for each color.

[0076] Alternatively, the number of rotations of beverage can 10 from the start of formation of large dot image 102 in large outer diameter region 11J to the end of formation of large dot image 102 in large outer diameter region 11J may be set to be greater than the number of rotations of beverage can 10 from the start of formation of small dot image 102 in small outer diameter region 11K to the end of formation of small dot image 102. In this case, for example, during the first downstream movement of the movable body 230, a large dot image 102 is formed in the large outer diameter region 11J, and a small dot image 102 is formed in the small outer diameter region 11K.

[0077] Thereafter, the movable body 230 is returned to the side of the input section 201. Next, when the movable body 230 moves downstream for the second time, new large dot images 102 are formed between the large dot images 102 already formed in the large outer diameter region 11J. At this time, no dot images 102 are formed in the small outer diameter region 11K. As a result, in this case, the number of large dot images 102 formed in the large outer diameter region 11J and arranged in the circumferential direction of the beverage can 10 is greater than the number of small dot images 102 formed in the small outer diameter region 11K and arranged in the circumferential direction of the beverage can 10. Additionally, the large dot image 102 may be formed again in the large outer diameter region 11J while the moving body 230 is returning to the insertion portion 201. In this case, the second large dot image 102 is formed in the order of the fourth inkjet head 19K to the first inkjet head 19C.

[0078] When forming a large dot image 102 in the large outer diameter region 11J, if a new large dot image 102 is to be formed between large dot images 102 that have already been formed, as described above, an encoder or the like is used to identify the phase in the rotational direction of the beverage can 10. Specifically, for example, the moving body 230 is provided with an encoder that identifies the phase of the beverage can 10 in the rotational direction. This encoder is then used to identify the phase of the beverage can 10 when the large dot image 102 is formed during the first downstream movement of the moving body 230.

[0079] Then, when a new large dot image 102 is formed during the second downstream movement of the moving body 230, the timing of forming the new large dot image 102 during this second downstream movement is determined based on the identified phase and information about the phase newly acquired during this second downstream movement of the moving body 230. Specifically, the timing for forming the large dot image 102 during the second movement of the moving body 230 in the downstream direction is determined so that the new large dot image 102 is positioned between the large dot images 102 that have already been formed.

[0080] The processing after the formation of the dot image 102 will be described. In this embodiment, once the printing unit 210 forms the dot image 102 and the image 101 is formed on the beverage can 10, the moving body 230 moves toward the image curing unit 220 (see FIG. 2). Note that in this embodiment, even at this time, the beverage can 10 continues to rotate in the circumferential direction. The image curing unit 220, which is an example of a curing means, is provided at a location different from the location of the printing unit 210 in the movement direction of the movable body 230. The image curing unit 220 is provided upstream of the printing unit 210 in the downstream movement direction.

[0081] The image curing unit 220 hardens the image 101 formed on the outer peripheral surface 11M of the beverage can 10 by the printing unit 210. The image curing unit 220 is provided with a light source 221, and the image curing unit 220 irradiates light onto the beverage can 10 after printing by the printing unit 210. More specifically, the image curing unit 220 irradiates the image 101 formed on the outer peripheral surface 11M of the beverage can 10 with ultraviolet light. This hardens the image 101 formed on the outer peripheral surface 11M of the beverage can 10. In other words, the dot image 102 formed on the outer peripheral surface 11M of the beverage can 10 hardens.

[0082] As described above, the printing unit 210 forms the image 101 using ultraviolet curable ink. In other words, the printing unit 210 forms the image 101 using actinic radiation curable ink. Therefore, when the image curing unit 220 irradiates the image 101 with ultraviolet light, the image 101 is cured.

[0083] The ink used to form the image 101 is not limited to ultraviolet curable ink, and other types of ink such as heat curable ink may also be used. When thermosetting ink is used as the ink used to form the image 101, the image curing unit 220 is provided with a heat source. The image 101 can be formed using any ink that has been conventionally used, and the ink used to form the image 101 is not particularly limited. In other words, the image 101 can be formed using any known ink that has been conventionally used for printing on beverage cans 10, and is not particularly limited. When the image curing unit 220 finishes curing the image 101 , the moving body 230 returns to the insertion unit 201 .

[0084] In this embodiment, as described above, the beverage can 10 moves in the downstream movement direction, which is an example of one direction, with the one end 11A side of the beverage can 10 in the axial direction leading the way. During this movement, image 101 is formed on outer peripheral surface 11M of beverage can 10. Then, in image hardening section 220, this formed image 101 is hardened. When the image 101 is hardened, the moving body 230 moves in the upstream movement direction, and the beverage can 10 moves in this upstream movement direction. Then, the moving body 230 and the beverage can 10 reach the insertion section 201.

[0085] When the moving body 230 and the beverage can 10 reach the insertion section 201, the worker removes the beverage can 10 on which printing has been completed from the moving body 230. Next, the worker places a new beverage can 10 on the moving body 230. In the above description, the image curing unit 220 is provided upstream of the printing unit 210 in the downstream movement direction, but the installation position of the image curing unit 220 is not limited to this. Alternatively, the image curing unit 220 may be provided downstream of the printing unit 210 in the downstream movement direction.

[0086] FIG. 7 is a diagram showing another example of the configuration of the beverage can 10. In this configuration example, one end 11A of a beverage can 10 is provided with a tapered portion 11 whose outer diameter decreases toward an opening 11E. 7, a can body 31, which is an example of a body portion, is not tapered. In this configuration example, a can body 31 that is not tapered or that has a smaller degree of diameter reduction than the reduced diameter portion 11 is provided on the bottom 11F side of the reduced diameter portion 11. In this configuration example shown in FIG. 7, the outer diameter of one end 31A of the can body 31 is approximately equal to the outer diameter of the other end 31B. In this configuration example, a can body 31 is provided as an example of a non-reduced diameter portion, which is a portion of the beverage can 10 other than the reduced diameter portion 11.

[0087] FIG. 8 is a diagram showing a printing device 100 that prints on the beverage can 10 shown in FIG. In this configuration example shown in FIG. 8, a moving body 230 is provided with a change mechanism 300 that changes the inclination of the beverage can 10 relative to the horizontal direction. The change mechanism 300 moves the outer rotation shaft 262B provided on the outer member 262 up and down to change the inclination of the beverage can 10 relative to the horizontal direction.

[0088] The configuration of the changing mechanism 300 is not particularly limited. The change mechanism 300 can be realized by, for example, a drive motor and a cam configured by this drive motor. When the cam rotates, the outer rotation shaft 262B, which is supported from below by the outer periphery of the cam, moves up and down, and accordingly the inclination of the beverage can 10 relative to the horizontal direction changes. Alternatively, the change mechanism 300 may be configured by, for example, a solenoid, and the outer rotation shaft 262B may be moved up and down depending on whether the solenoid is turned on or off.

[0089] In the configuration example shown in FIG. 8, when the printing unit 210 forms the image 101, the beverage can 10 is placed on the moving body 230 at the insertion unit 201 in the same manner as described above. At this time, the beverage can 10 is placed with the axis 10G of the beverage can 10 aligned horizontally. In this embodiment, in this state, the moving body 230 moves toward the printing unit 210, and the image 101 is formed on the can body 31.

[0090] Thereafter, in this configuration example, the moving body 230 returns to the insertion section 201 side. Next, as shown by reference symbol 8B, the inclination of beverage can 10 with respect to the horizontal direction is changed by change mechanism 300, and beverage can 10 is brought into the state shown by reference symbol 8C. Specifically, beverage can 10 is brought into a state in which axis 10G of beverage can 10 is inclined with respect to the horizontal direction.

[0091] When the axis 10G of the beverage can 10 is tilted relative to the horizontal, the small outer diameter center 54 of the reduced diameter portion 11 of the beverage can 10 is positioned higher than the large outer diameter center 55. Furthermore, when the axis 10G of the beverage can 10 is tilted relative to the horizontal direction, the portion 11H of the reduced diameter portion 11 of the beverage can 10 that is positioned on the inkjet head 19 side faces the inkjet head 19.

[0092] After the axis 10G of the beverage can 10 is tilted relative to the horizontal direction, the moving body 230 moves again toward the printing unit 210, and the image 101 is formed on the reduced diameter portion 11. Incidentally, when image 101 is formed on reduced diameter portion 11, beverage can 10 is also rotated in the circumferential direction. After the formation of the image 101 in the reduced diameter section 11 is completed, the beverage can 10 moves to the image curing section 220.

[0093] Then, in the image curing section 220, light is irradiated onto the can body 31 and the reduced diameter section 11. As a result, the image 101 formed on the can body 31 and the reduced diameter section 11 is cured. At this time, the axis 10G of the beverage can 10 may be returned to the horizontal direction. In other words, when the image hardening unit 220 irradiates the beverage can 10 with light, the axis 10G of the beverage can 10 may be aligned with the horizontal direction. In other words, the beverage can 10 may be irradiated with light while the axis 10G is aligned with the horizontal direction. In this case, the entire can body 31 is more reliably irradiated with light. Thereafter, the moving body 230 returns to the insertion section 201 in the same manner as above. Then, the beverage can 10 on which the image 101 has been formed is removed from the moving body 230 by the worker. Next, a new beverage can 10 is placed on the moving body 230 by the worker.

[0094] In the configuration example shown in FIG. 8, the rotation mechanism 250 is also provided with a gear change mechanism (not shown) that changes the angle and position of the drive gear 251 (see FIG. 5(B)). As a result, even if the angle and position of the receiving gear 261D (see FIG. 4) are changed due to a change in the inclination of the beverage can 10, the meshing between the receiving gear 261D and the drive gear 251 is maintained. More specifically, in this embodiment, the gear change mechanism operates based on an instruction from the control unit 60 (see FIG. 3), and the angle and position of the drive gear 251 are changed.

[0095] In this embodiment, the inclination of the beverage can 10 relative to the horizontal direction is changed by the control unit 60, and at this time, the control unit 60 outputs a control signal that changes the angle and position of the drive gear 251. As a result, even if the angle and position of the receiving gear 261D change in response to a change in the inclination of the beverage can 10, the meshing between the receiving gear 261D and the drive gear 251 is maintained. The gear change mechanism is not particularly limited. The gear change mechanism may use any known technology that is used to change the position and angle of an object. For example, known technology such as a motor, a cam, a link, a rack and pinion, or a solenoid may be used.

[0096] In addition, in the above description, a case has been described in which the inclination of the beverage can 10 is changed after the beverage can 10 has completed forming the image 101 on the can body 31 and returned to the insertion section 201 side, but the timing of changing the inclination of the beverage can 10 is not limited to this. For example, the inclination of beverage can 10 may be changed while beverage can 10, after image 101 has been formed on can body 31, is returning to the insertion section 201 side. Also, for example, the inclination of a beverage can 10 that has completed the formation of an image 101 on the can body 31 and has returned to the insertion section 201 side may be changed while the beverage can 10 is heading back to the printing section 210.

[0097] Additionally, when forming image 101 on reduced diameter portion 11 of beverage can 10 shown in FIGS. 7 and 8, the same process as above may be carried out. That is, when forming an image 101 on the reduced diameter portion 11 of the beverage can 10 shown in Figures 7 and 8, the above-mentioned processing may be performed, for example, to make the size of the dot image 102 formed on the large outer diameter portion 11X (see Figure 8) larger than the size of the dot image 102 formed on the small outer diameter portion 11Y.

[0098] In addition, the above processing may be performed to make the number of dot images 102 formed in the large outer diameter portion 11X of the narrowed diameter portion 11 and arranged in the circumferential direction of the beverage can 10 greater than the number of dot images 102 formed in the small outer diameter portion 11Y of the narrowed diameter portion 11 and arranged in the circumferential direction of the beverage can 10. In addition, the above processing may be performed to make the size of the dot images 102 formed in the large outer diameter portion 11X of the narrowing portion 11 larger than the size of the dot images 102 formed in the small outer diameter portion 11Y of the narrowing portion 11, and to make the number of dot images 102 formed in the large outer diameter portion 11X of the narrowing portion 11 and arranged in the circumferential direction of the beverage can 10 larger than the number of dot images 102 formed in the small outer diameter portion 11Y of the narrowing portion 11 and arranged in the circumferential direction of the beverage can 10.

[0099] In this configuration example shown in Figure 8, the posture of beverage can 10 when image 101 is formed on can body 31 is different from the posture of beverage can 10 when image 101 is formed on reduced diameter portion 11. In other words, in this configuration example, the inclination of the beverage can 10 relative to the horizontal direction when the image 101 is formed on the can body 31 is different from the inclination of the beverage can 10 relative to the horizontal direction when the image 101 is formed on the reduced diameter portion 11.

[0100] In this configuration example, the inclination of the beverage can 10 is changed according to the portion of the beverage can 10 on which the image 101 is to be formed. 7 and 8 has a plurality of portions, such as the can body 31 and the reduced diameter portion 11, which have different inclinations relative to the axial direction of the beverage can 10. In this embodiment, the inclination of the beverage can 10 is changed according to each of the portions included in the plurality of portions. This improves the quality of the image 101 formed on the beverage can 10 compared to when the inclination of the beverage can 10 is not changed at all and the image 101 is formed for each of the multiple parts under a single inclination.

[0101] In the above description, the image 101 is formed on the can body 31 first, and then the image 101 is formed on the reduced diameter portion 11. However, the present invention is not limited to this, and the image 101 may be formed on the reduced diameter portion 11 first, and then the image 101 may be formed on the can body portion 31. In this case, as in the above case, when image 101 is formed on reduced diameter portion 11, beverage can 10 is positioned in a state tilted relative to the horizontal. Furthermore, when image 101 is formed on can body 31, beverage can 10 is positioned in a state aligned with the horizontal.

[0102] (others) In the above, the size and number of dot images 102 are made different between the large outer diameter region 11J located closer to the large outer diameter portion 11X than the intermediate portion 11Z (see Figure 1(A)) and the small outer diameter region 11K located closer to the small outer diameter portion 11Y than the intermediate portion 11Z, but the manner in which the dot images 102 are formed is not limited to this. For example, the dot image 102 may be formed so that the dot image 102 gradually becomes larger from the small outer diameter portion 11Y of the reduced diameter portion 11 toward the large outer diameter portion 11X. Alternatively, the dot images 102 may be formed so that, for example, the number of dot images 102 included in a row of dot images aligned circumferentially around the beverage can 10 gradually increases from the small outer diameter portion 11Y of the narrowed portion 11 toward the large outer diameter portion 11X.

[0103] Furthermore, although the above describes processing that is based on the assumption that the sizes of the dot images 102 are made different, it is also possible to form the dot images 102 without making the sizes of the dot images 102 different, and instead making all the dot images 102 the same size. Furthermore, in the above, a process has been described in which the number of large dot images 102 arranged circumferentially in the large outer diameter region 11J is made greater than the number of small dot images 102 arranged circumferentially in the small outer diameter region 11K, but the dot images 102 may be formed without varying the number of dot images 102, with the number of dot images 102 all being the same. Alternatively, the dot images 102 may be formed by keeping the number of dot images 102 the same for all, without varying the number of dot images 102, and keeping the size of the dot images 102 the same for all, without varying the size of the dot images 102.

[0104] In addition, in the above, an example has been described in which the size of one dot image 102 is changed by changing the amount of ink contained in one drop of ink ejected from the inkjet head 19, but the size of one dot image 102 may also be changed in other ways. For example, the size of one dot image 102 may be changed by changing the number of times ink is ejected when forming one dot image 102.

[0105] For example, when forming one large dot image 102, the number of times ink is ejected from one ink ejection port corresponding to this one large dot image 102 may be increased to form this one large dot image 102. Furthermore, when forming one small dot image 102, the number of times ink is ejected from one ink ejection port corresponding to this one small dot image 102 may be reduced to form this one small dot image 102. [Explanation of symbols]

[0106] 10...beverage can, 10G...axial center, 11...reduced diameter portion, 11M...outer peripheral surface, 11X...large outer diameter portion, 11Y...small outer diameter portion, 19...inkjet head, 54...small outer diameter center portion, 55...large outer diameter center portion, 92...opposing portion, 100...printing device, 100R...moving path, 101...image, 102...dot image, 210...printing portion, 220...image curing portion, 230...moving body, 250...rotation mechanism, 300...changing mechanism

Claims

1. a moving body that supports and moves a cylindrical beverage container, the moving body including a rotation mechanism that rotates the container in a circumferential direction, so that one end side of the container in the axial direction moves first; a printing unit that prints on the outer peripheral surface of the container that is supported by the moving body and moves while rotating in a circumferential direction; A printing device comprising:

2. the container is provided with a reduced diameter section whose outer diameter decreases as it progresses in the axial direction of the container, and the reduced diameter section is provided with a large outer diameter portion and a small outer diameter portion which are located at different positions in the axial direction of the container; a printing condition when the printing unit prints on the large outer diameter portion is different from a printing condition when the printing unit prints on the small outer diameter portion; The printing device of claim 1 .

3. the printing unit performs printing on the outer peripheral surface of the container using an inkjet head; the frequency of ink ejection by the printing unit onto the large outer diameter portion is greater than the frequency of ink ejection by the printing unit onto the small outer diameter portion; The printing device according to claim 2 .

4. the printing unit uses an inkjet head to form a dot image on the outer peripheral surface of the container, and performs printing on the outer peripheral surface; the number of rotations of the container from the start of formation of the dot image on the large outer diameter portion to the end of formation of the dot image is greater than the number of rotations of the container from the start of formation of the dot image on the small outer diameter portion to the end of formation of the dot image. The printing device according to claim 2 .

5. the printing unit performs printing on the outer peripheral surface of the container using an inkjet head; a rotation speed of the container when the printing unit ejects ink onto the large outer diameter portion is lower than a rotation speed of the container when the printing unit ejects ink onto the small outer diameter portion. The printing device according to claim 2 .

6. the printing unit uses an inkjet head to form a dot image on the outer peripheral surface of the container, and performs printing on the outer peripheral surface; a dot image formed by the printing unit on the large outer diameter portion is larger than a dot image formed by the printing unit on the small outer diameter portion; The printing device according to claim 2 .

7. The printing unit prints on the outer peripheral surface of the container while the container moves in one direction with the one end side in the axial direction of the container leading the way, After the printing unit prints on the outer peripheral surface, the movable body moves in a direction opposite to the one direction, and the container moves in the opposite direction. The printing device of claim 1 .

8. a curing unit that cures the image formed on the outer peripheral surface of the container by the printing unit, at a location different from the location where the printing unit is installed in the moving direction of the moving body; The printing device of claim 1 .

9. The container has a tapered portion whose outer diameter decreases along the axial direction of the container, When the container is moved by the moving body, the container moves with the axis of the container tilted relative to the horizontal direction. The printing device of claim 1 .

10. the reduced diameter portion is provided with a large outer diameter portion and a small outer diameter portion that are positioned at different positions in the axial direction of the container, When the container is moved by the moving body, a center portion in a radial direction of the small outer diameter portion is located higher than a center portion in a radial direction of the large outer diameter portion. The printing device according to claim 9.

11. the reduced diameter portion of the container is provided so as to reduce in diameter at a constant rate as it progresses in the axial direction of the container, When the printing unit prints on the container, a portion of the outer circumferential surface of the reduced diameter unit that faces the printing unit is arranged in a horizontal direction. The printing device of claim 9.

12. The moving body is further provided with a change mechanism for changing the inclination of the container relative to the horizontal direction. The printing device of claim 1 .

13. The printing unit is provided with a plurality of inkjet heads that eject ink in different colors, printing on the outer peripheral surface by depositing ink from the plurality of inkjet heads on the outer peripheral surface; The printing device of claim 1 .

14. the inkjet heads are provided at positions offset from one another in the moving direction of the moving body; The printing device of claim 13.

15. the container is placed on the movable body at an insertion unit where the container is inserted into the printing device; After the container is placed on the moving body, the moving body moves toward the printing unit along a predetermined moving path; After printing on the container by the printing unit, the moving body supporting the container returns to the input unit along the movement path that was taken when moving from the input unit toward the printing unit. The printing device of claim 1 .

Images