JP2020040718A - Printing equipment - Google Patents

Abstract

To increase the efficiency of printing on a can body as compared with a case where means for detecting a phase of the can body is provided on a body side of a printing equipment.SOLUTION: A printing equipment includes image forming means for forming an image on a can body 10, a plurality of moving bodes 550 that support the can body in a rotatable state and move toward the image forming means, and detecting means 570 provided on each of the moving bodies to detect a phase of the can body.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a printing device.

  Patent Literature 1 discloses a method of manufacturing a can body including a basic forming step of forming a material into a tubular element body and a printing step of performing a printing process on an outer peripheral surface of the element body formed in the basic molding step. Is disclosed.

JP 2008-183613 A

In printing on the can, a mode in which printing on the can is started after detecting the phase of the can in order to prevent deviation of the formed image or the like can be considered.
Here, for example, a mode in which a detecting means for detecting the phase of the can is provided at the installation position of the image forming means, and the phase of the can is detected after the can reaches the image forming means can be considered. By the way, in this case, the time required from when the can reaches the image forming means until the image formation is started becomes long, and the efficiency of printing on the can tends to decrease.
An object of the present invention is to increase the efficiency of printing on a can body as compared with a case where means for detecting the phase of the can body is provided on the main body side of the printing apparatus.

A printing apparatus to which the present invention is applied is an image forming unit that forms an image on a can, a plurality of moving bodies that support the can in a rotatable state, and move toward the image forming unit, A detection unit provided on each of the moving bodies and detecting a phase of the can body.
Here, the detection means may detect the phase of the rotating body that rotates in synchronization with the rotation of the can body, and may detect the phase of the can body.
Further, each of the moving bodies is provided with a transmission shaft for transmitting a rotational driving force to the can body, and a rotation center of the rotating body is located at a position off the transmission shaft. It can be.
The moving body may support a plurality of cans, and a phase of each of the plurality of cans may be detected by a common detection unit.
In addition, a driving source for rotating the can body supported by the moving body is provided, and the driving source is provided at a location different from the moving body.
Further, the driving force is transmitted from a driving source side rotating body provided on the driving source side to a moving body side rotating body provided on the moving body side, so that the can supported by the moving body is provided. The body may be characterized by rotating.
Further, by using the magnetic force, the moving body side rotating body rotates in synchronization with the driving source side rotating body, and the driving force is transmitted from the driving source side rotating body to the moving body side rotating body. It can be.
Further, when a driving force is transmitted from the driving source side rotating body to the moving body side rotating body, the driving source side rotating body and the moving body side rotating body are arranged in a non-contact state. be able to.
In addition, a transmission unit that is disposed along a moving path of the moving body, a part of the moving body comes into contact with the moving body, and transmits a detection result by the detection unit may be provided.
In addition, a plurality of the transmitting units may be provided, and the transmitting unit that the part of each of the moving objects contacts may be provided for each of the moving objects.
In addition, a plurality of the transmission units may be arranged side by side in a direction intersecting a direction in which the moving path of the moving body extends.
In addition, the position of the part in each of the plurality of moving bodies in the intersecting direction is different for each of the moving bodies, and the transmitting unit in which the part of each of the moving bodies comes into contact with the moving body has the movement. It can be characterized as being different for each body.

  ADVANTAGE OF THE INVENTION According to this invention, the printing efficiency with respect to a can can be improved compared with the case where the means which detects the phase of a can is provided in the main body side of a printing apparatus.

FIG. 2 is a side view of the printing apparatus. It is a figure explaining an inspection device. FIG. 6 is a diagram illustrating another configuration example of the printing apparatus. FIG. 4 is a diagram when a first inkjet head, a second inkjet head, and a moving unit are viewed from an arrow IV direction in FIG. 1. FIG. 5 is a diagram when the moving unit and the like are viewed from the direction of arrow V in FIG. 4.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.
FIG. 1 is a side view of the printing apparatus 500.
The printing apparatus 500 is provided with a can supply unit 510 to which the can 10 is supplied. In the can supply unit 510, the can 10 is supplied (attached) to the support member 20 that supports the can 10.
Specifically, the support member 20 is formed in a cylindrical shape, and the can 10 is supplied to the support member 20 by inserting the support member 20 into the cylindrical can 10.

Further, an inspection device 92 is provided in the can body supply section 510.
The inspection device 92 performs an inspection as to whether the can body 10 is not deformed.
More specifically, the inspection device 92 is provided with a light source 92A as shown in FIG. 2 (a diagram illustrating the inspection device 92).
The light source 92A is provided on one end side of the can body 10 and emits a laser beam traveling along the outer peripheral surface of the can body 10 and along the axial direction of the can body 10. Further, on the other end side of the can body 10, a light receiving section 92B for receiving a laser beam from the light source 92A is provided.

When a part of the can 10 is deformed as shown by the reference numeral 3A, the laser light is blocked, and the light receiving unit 92B does not receive the laser light. Thereby, the deformation of the can 10 is detected.
In the present embodiment, when the inspection device 92 determines that the can 10 does not satisfy the predetermined condition (when it is determined that the can 10 is deformed), the discharging mechanism 93 is used. (See FIG. 1), the can 10 is discharged out of the printing apparatus 500.

As shown in FIG. 1, the discharge mechanism 93 is disposed between the inspection device 92 and the inkjet printing unit 700 (located upstream of the inkjet printing unit 700).
In the present embodiment, the deformed can 10 is discharged from the printing apparatus 500 before image formation is performed by the inkjet printing unit 700.

In the discharge mechanism 93, compressed air is supplied to the inside of the cylindrical support member 20, and the can 10 moves in the axial direction (the direction orthogonal to the plane of FIG. 1).
Further, the bottom 10A (the end on the closed side) of the can 10 is sucked by a suction member (not shown). The suction member conveys the can body 10 to the outside of the printing apparatus 500, and discharges the can body 10 to the outside of the printing apparatus 500.

An inkjet printing unit 700 is provided downstream of the discharge mechanism 93.
The inkjet printing unit 700 as an example of an image forming unit uses an inkjet printing method to form an image on the can 10 that has moved from the upstream side.
In addition, in the present embodiment, in forming an image by the inkjet printing unit 700, the moving unit 550 sequentially moves from the upstream side of the inkjet printing unit 700 toward the inkjet printing unit 700 (see arrow 1A).
Then, in the present embodiment, an image is formed on the can 10 on the moving unit 550 by the inkjet printing unit 700.

Here, image formation by the inkjet printing method refers to image formation performed by discharging ink from the inkjet head 11 and attaching the ink to the can 10.
In image formation by an inkjet printing method, a known method can be used. Specifically, for example, a piezo method, a thermal (bubble) method, a continuous method, or the like can be used.

A light irradiation unit 750 as an example of a light irradiation unit is provided downstream of the inkjet printing unit 700.
The light irradiating unit 750 includes a light source, irradiates the outer peripheral surface of the can 10 on which the image is formed by the inkjet printing unit 700 with light, and cures the image formed on the outer peripheral surface.

In the inkjet printing unit 700, an image is formed using an ultraviolet curable ink. In addition, in the inkjet printing unit 700, an image is formed using an actinic radiation curable ink.
The light irradiation section 750 irradiates the formed image with light such as ultraviolet rays. As a result, the image formed on the outer peripheral surface of the can 10 is cured.
Here, the inkjet printing unit 700 and the light irradiation unit 750 are arranged on the side of the first linear portion 810 (details will be described later).

The protective layer forming section 770 is disposed downstream of the inkjet printing section 700 and the light irradiation section 750.
The protective layer forming section 770 deposits a transparent paint on the image formed by the inkjet printing section 700, and forms a transparent layer covering the image. Thereby, in this embodiment, a transparent protective layer is formed on the outermost layer of the can body 10.

On the downstream side of the protective layer forming section 770, a detaching section 780 for detaching the can 10 from the support member 20 is provided.
In the present embodiment, the can 10 is detached from the support member 20 at the detaching section 780, and the can 10 is discharged out of the printing apparatus 500.
Further, the printing apparatus 500 is provided with a plurality of moving units 550 as an example of a moving body that moves while supporting the can body 10.

In the present embodiment, the support member 20 that supports the can 10 is attached to the moving unit 550, and the can 10 moves together with the moving unit 550.
Although FIG. 1 shows a case where the moving unit 550 is supported by one can body 10, as will be described later (as shown in FIG. 4), the moving unit 550 has two (plural) cans. The body 10 may be placed, and one moving unit 550 may support a plurality of cans 10.
When one moving unit 550 supports a plurality of cans 10, a plurality of inkjet heads 11 are installed at each stop point P of the moving unit 550, as described later (as shown in FIG. 4). You.

The support member 20 (see FIG. 1) is formed in a cylindrical shape, and is provided so as to be rotatable in a circumferential direction.
In the present embodiment, since the can body 10 is supported by the support member 20 rotatable in the circumferential direction, the can body 10 is also supported in a state rotatable in the circumferential direction.

The can body 10 is formed in a cylindrical shape, and has an opening at one end. The other end of the can 10 is closed, and the other end is provided with a bottom 10A. The support member 20 is inserted into the can 10 from this opening.
Further, in the present embodiment, a moving mechanism 560 that functions as a moving unit that moves the moving unit 550 is provided. The moving mechanism 560 is provided with an annular guide member 561 for guiding the moving unit 550.

Each of the moving units 550 is guided by a guide member 561 and performs a circular movement along a predetermined annular moving path 800.
Accordingly, in the present embodiment, the support member 20 provided in the moving unit 550 and the can body 10 supported by the support member 20 also move along the predetermined annular movement path 800.

The movement path 800 is arranged so that its axial center 800C extends along the horizontal direction. In other words, the movement path 800 is arranged around the axial center 800C along the horizontal direction. Here, the axial center 800C extends in a direction orthogonal to the paper surface of FIG.
In this case, in the present embodiment, the support member 20 and the can body 10 make a revolving movement around the axial center 800C extending along a direction orthogonal to the paper surface in the drawing.

The moving path 800 is provided with a first linear part 810 that is a linear moving path, and a second linear part 820 that is also a linear moving path.
Each of the first linear portion 810 and the second linear portion 820 is disposed so as to extend along the horizontal direction. Further, the first linear portion 810 and the second linear portion 820 are arranged in a substantially parallel relationship. Further, in the present embodiment, the first linear portion 810 is disposed above the second linear portion 820.

Further, the first linear portion 810 is provided at the uppermost portion of the annular moving route 800, and the second linear portion 820 is provided at the lowermost portion of the annular moving route 800. I have.
Further, in the present embodiment, the inkjet printing unit 700 is provided above the first linear portion 810 located at the uppermost position.

Further, the movement path 800 is provided with a first curved portion 830 and a second curved portion 840 which have a curvature and are formed so as to draw an arc.
The first curved portion 830 connects the right end of the first straight portion 810 in the drawing and the right end of the second straight portion 820 in the drawing. Further, the first curved portion 830 is formed so as to go from above to below.
Further, the second curved portion 840 connects the left end of the first straight portion 810 in the drawing and the left end of the second straight portion 820 in the drawing. In addition, the second curved portion 840 is formed so as to go upward from below.

Next, the inkjet printing unit 700 will be described.
The inkjet printing unit 700 is arranged above the first linear portion 810 and forms an image on the can 10 located on the first linear portion 810.
The inkjet printing section 700 is provided with a plurality of inkjet heads 11 arranged side by side in the left-right direction in the figure. The portion where the plurality of inkjet heads 11 are provided can be regarded as image forming means for forming an image on the can 10.

Specifically, the inkjet printing unit 700 includes a first inkjet head 11C for ejecting cyan ink, a second inkjet head 11M for ejecting magenta ink, a third inkjet head 11Y for ejecting yellow ink, and a black inkjet head 11Y. A fourth inkjet head 11K that ejects ink is provided.
In the following description, the first inkjet head 11 </ b> C to the fourth inkjet head 11 </ b> K are simply referred to as “inkjet head 11” unless otherwise distinguished.

  In the present embodiment, the case where four ink jet heads 11 are provided is exemplified. However, the ink jet head 11 for discharging a special color ink such as a corporate color or the like, and the ink jet head for forming a white layer. 11 may be further provided.

Here, the four inkjet heads 11 of the first inkjet head 11C to the fourth inkjet head 11K perform image formation on the can 10 using ultraviolet curable ink.
In the present embodiment, the can body 10 moves while lying down (the can body 10 moves while the axial direction of the can body 10 is horizontal), and a part of the outer peripheral surface of the can body 10 is It faces upward in the vertical direction.
In the present embodiment, ink is ejected downward from above the outer peripheral surface to form an image on the outer peripheral surface of the can body 10.

In the present embodiment, the moving unit 550 is stopped below each inkjet head 11, the ink is discharged to the can 10 on the moving unit 550, and the image is formed on the can 10. .
Then, in this embodiment, when the image formation on the can 10 is completed, the moving unit 550 moves toward the inkjet head 11 located one downstream, and the inkjet head 11 moves the can 10 to the can 10. Is further performed.

Further, in the present embodiment, the four inkjet heads 11 are arranged in a state where they are arranged in the moving direction of the can 10. Further, each of the four inkjet heads 11 is arranged along a direction orthogonal (intersecting) to the moving direction of the can 10.
In the present embodiment, as the can 10 passes under these four ink-jet heads 11, ink is ejected from above onto the can 10 to form an image on the can 10.

More specifically, in the present embodiment, the moving unit 550 stops at each installation location of the plurality of inkjet heads 11 provided.
Then, in each of the ink jet heads 11, the ink is discharged to the can 10, and an image is formed on the can 10. When an image is formed by each ink jet head 11, the can 10 rotates in the circumferential direction.

Each of the moving units 550 as an example of the moving body moves at a predetermined moving speed.
Further, each of the moving units 550 stops at each of the can body supply unit 510, the inspection device 92, the discharge mechanism 93, each ink jet head 11, the light irradiation unit 750, the protective layer forming unit 770, and the removal unit 780.

In addition, at the installation locations of the inspection device 92, the respective inkjet heads 11, the light irradiation unit 750, the protective layer forming unit 770, etc., the can 10 on the moving unit 550 rotates in the circumferential direction at a predetermined rotation speed. Do.
Further, in the printing apparatus 500 of the present embodiment, the moving units 550 that are larger in number than the number of the cans 10 located in the printing apparatus 500 are installed. Further, the moving unit 550 moves around the axial center 800C.

The moving mechanism 560 is provided with an annular guide member 561 for guiding the moving unit 550. An electromagnet (not shown) is provided inside the guide member 561.
Further, a permanent magnet (not shown) is installed in the moving unit 550.
In the present embodiment, the moving unit 550 is moved using a linear mechanism.

  More specifically, in the printing apparatus 500 of the present embodiment, a control unit 900 is provided, and the control unit 900 controls the energization of the electromagnet to generate a magnetic field, and each of the moving units 550 To move. The control unit 900 is configured by a CPU (Central Processing Unit) controlled by a program.

As shown in FIG. 1, the moving unit 550 is provided with a pedestal portion 551 guided by a guide member 561. The pedestal 551 is provided with a permanent magnet (not shown).
In this embodiment, a propulsive force is generated in the moving unit 550 by the magnetic field generated by the electromagnet provided in the guide member 561 and the permanent magnet provided in the pedestal portion 551 of the moving unit 550. Along the travel path 800 of the vehicle.

  Further, the moving unit 550 of the present embodiment is provided with a cylindrical support member 20 for supporting the can 10 and a fixing member 553 for fixing the support member 20 to the pedestal 551. The fixing member 553 is provided so as to stand up from the pedestal 551.

The support member 20 of the present embodiment is formed in a cylindrical shape, is inserted into the can 10 through an opening formed in the can 10, and supports the can 10. The support member 20 is arranged in a lying state (a state along the horizontal direction). Thereby, in this embodiment, the can body 10 is also arranged in a lying state.
In the present embodiment, when the cans 10 reach each of the inkjet heads 11, ink is ejected from each of the inkjet heads 11 to the cans 10 located below. Thereby, an image is formed on the outer peripheral surface of the can 10.

The light irradiation unit 750 is disposed downstream of the inkjet printing unit 700, and irradiates the can body 10 with ultraviolet light, which is an example of light. Thereby, the image formed on the outer peripheral surface of the can body 10 (the image formed by the inkjet printing unit 700) is cured.
In forming an image on the can 10, a thermosetting ink may be used. In this case, for example, a heat source instead of a light source is provided at a position where the light irradiation unit 750 is provided.

In the present embodiment, the moving unit 550 stops every time it reaches below each inkjet head 11. In other words, the mobile unit 550 stops at each of the predetermined stop locations.
In the present embodiment, an image is formed on the outer peripheral surface of the can body 10 held by the moving unit 550 stopped at the predetermined stop position by the inkjet head 11 as an example of an image forming unit. Is done.

More specifically, at each installation location of the inkjet head 11, the ink is ejected from the inkjet head 11 while the support member 20 (can body 10) is rotating in the circumferential direction, and An image is formed on the outer peripheral surface of the reference numeral 10.
In the present embodiment, when the support member 20 rotates 360 ° after the start of the ink discharge, the ink discharge stops. Thus, an image is formed on the entire outer circumferential surface of the can body 10 in the circumferential direction.

In the present embodiment, the support member 20 shown in FIG. 1 is arranged along a direction orthogonal to the paper surface of FIG. In other words, the support member 20 is arranged to extend along the horizontal direction.
Further, the support member 20 is arranged along a direction orthogonal (intersecting) with the moving direction of the moving unit 550.

In the present embodiment, the inkjet head 11 is located above the can 10, and ink is ejected onto the can 10 from above.
In this case, the influence of gravity acting on the ink droplets ejected from the inkjet head 11 can be reduced as compared with the case where the inkjet head 11 is arranged on the side of the can 10 or below the can 10. The accuracy of the ink attachment position on the body 10 can be improved.

Further, in the present embodiment, the inkjet printing unit 700 (the plurality of inkjet heads 11) is provided on the side (upper side) of the first linear portion 810.
Thereby, compared to the case where the inkjet printing unit 700 (the plurality of inkjet heads 11) is provided on the side of the curved portion (the first curved portion 830 and the second curved portion 840), the can body 10 is formed. Image quality can be easily improved.

Here, when the inkjet head 11 is provided on the side of the curved portion, for example, as illustrated in FIG. 3 (a diagram illustrating another configuration example of the printing apparatus 500), the posture of the inkjet head 11 is It becomes different for each head 11.
In this case, as compared with the case where the postures of the inkjet heads 11 are aligned, the quality of the formed image is more likely to be deteriorated, such as a positional shift between the images formed for each inkjet head 11.

  On the other hand, when the inkjet printing unit 700 is provided on the side of the linear portion (the first linear portion 810) as in the present embodiment, the postures of the plurality of inkjet heads 11 are easily aligned and formed. Deterioration of image quality can be suppressed.

FIG. 4 is a diagram when the first inkjet head 11C, the second inkjet head 11M, and the moving unit 550 are viewed from the direction of arrow IV in FIG.
In FIG. 4, the moving unit 50 located immediately below the second inkjet head 11M is not shown.

Although not shown in FIG. 1, in the present embodiment, as shown in FIG. 4, a servo motor M as an example of a driving source for rotating the can 10 is provided at each stop point P where the moving unit 550 stops. Is provided.
In addition, a servo motor M that rotates the can 10 supported by the moving unit 550 is provided beside the moving path R of the moving unit 550.

In the present embodiment, the drive source (servo motor M) for rotating the can 10 is not provided in the moving unit 550, but is provided on the main body side of the printing apparatus 500 (see FIG. 1).
In addition, in the present embodiment, the driving source for rotating the can 10 is not provided in the moving unit 550, but is provided in a location different from the moving unit 550.
Accordingly, the weight of the moving unit 550 is reduced, and the shaking of the printing apparatus 500 due to the movement of the moving unit 550 is reduced.

Here, when the driving unit is provided in the moving unit 550 and the weight of the moving unit 550 is large, the shaking of the printing apparatus 500 when the moving unit 550 stops or the like is likely to increase. Then, in this case, the ink jet head 11 and the like are shaken, and the image quality is likely to be deteriorated.
On the other hand, in a configuration in which the driving source is provided on the main body side of the printing apparatus 500 as in the present embodiment, the weight of the moving unit 550 is reduced, and the shaking of the printing apparatus 500 when the moving unit 550 stops or the like. Becomes smaller.

As shown in FIG. 4, a pedestal portion 551 is provided in the moving unit 550.
Further, two cans 10 are provided on the pedestal portion 551. A support member 20 is inserted into each of the can bodies 10, and the can body 10 is supported by the support member 20.
Further, the moving unit 550 is provided with a transmission shaft 555 for transmitting a rotational driving force to the can 10. In this embodiment, the rotational driving force from the servomotor M is transmitted through the transmission shaft 555 in the can unit 10. It is transmitted to 10.

More specifically, in the present embodiment, a rotating gear 556 that contacts each of the support members 20 and rotates the support member 20 is provided, and the rotating gear 556 is rotated by the transmission shaft 555, so that the can body 10 rotates in the circumferential direction. In the present embodiment, the two cans 10 provided in each of the moving units 550 rotate in the same direction.
Further, in the present embodiment, a phase detection mechanism 570 is provided as an example of a detection unit that detects the phase of the can 10.

The phase detection mechanism 570 is provided with an encoder 571.
The encoder 571 is a known encoder 571, and is provided with a rotating body 571A that rotates in synchronization with the can body 10. The rotating body 571A has a slit (not shown) extending in the radial direction of the rotating body 571A.

Although not shown, the encoder 571 is provided with a light source that emits light to the rotating body 571A and a light receiving unit that receives light that has passed through the slit.
In the present embodiment, the phase (rotation angle) of the rotating body 571A is detected, and the phase (rotation angle) of the can 10 is detected.

In the present embodiment, the rotating body 571A is arranged such that the rotation center 571B of the rotating body 571A is located at a position off the transmission shaft 555.
Here, if the rotation center 571B of the rotating body 571A is located on the transmission shaft 555 (assuming that the encoder 571 is located on the transmission shaft 555), the direction indicated by reference numeral 4A (movement) The size of the moving unit 550 in the direction perpendicular to the moving direction of the unit 550) tends to increase.
On the other hand, if the rotation center 571B of the rotating body 571A is located at a position off the transmission shaft 555, the size of the moving unit 550 in the direction indicated by reference numeral 4A can be easily reduced.

Further, the phase detection mechanism 570 is provided with a transmission mechanism 572 that transmits the rotational driving force from the transmission shaft 555 to the encoder 571.
The transmission mechanism 572 includes a first rotating body 572A formed in a columnar shape and arranged coaxially with the transmission shaft 555, a circulating belt 572B that orbits by receiving a driving force from the first rotating body 572A, A second rotating body 572C that is arranged coaxially with 571A and rotates by receiving a driving force from a circulation belt 572B is provided.
In the present embodiment, a rotational driving force is transmitted from the transmission shaft 555 to the encoder 571 by the transmission mechanism 572, and the rotating body 571A rotates.

In the present embodiment, a plurality of cans 10 are provided in each of the moving units 550, and a phase of each of the plurality of cans 10 is detected by a common phase detection mechanism 570.
In addition, in this embodiment, the phase detection mechanism 570 is not provided for each of the cans 10, and one phase detection mechanism 570 is provided for two cans 10.
This makes it possible to reduce the weight of the moving unit 550 and reduce the number of parts, as compared with the case where the phase detection mechanism 570 is provided for each can 10.

Here, in the present embodiment, the transmission of the driving force from the servo motor M, which is the driving source, to the moving unit 550 is performed by a so-called magnet coupling.
Specifically, in the present embodiment, a drive source side rotating body 581 that is rotated by the servo motor M is provided on the servo motor M side (the main body side of the printing apparatus 500).

Further, in the present embodiment, a moving body side rotating body 582 disposed coaxially with the transmission shaft 555 is provided on the moving unit 550 side.
In the present embodiment, the can body 10 is rotated by transmitting the driving force from the driving source side rotating body 581 to the moving body side rotating body 582.

More specifically, in the present embodiment, by using magnetic force, the moving body-side rotating body 582 rotates in synchronization with the driving source-side rotating body 581, and from the driving source-side rotating body 581 to the moving body-side rotating body 582. Driving force is transmitted.
In addition, in this embodiment, one or both of the driving source side rotating body 581 and the moving body side rotating body 582 is provided with a magnet, and the other is provided with a to-be-sucked body sucked by the magnet.

Thus, in the present embodiment, the moving body-side rotating body 582 is rotated in synchronization with the drive source-side rotating body 581 using the magnetic force generated by the magnet.
Then, in the present embodiment, when the moving body side rotating body 582 rotates, the transmission shaft 555 rotates accordingly, and accordingly, the can body 10 rotates in the circumferential direction.

In the present embodiment, when the driving force is transmitted from the driving source side rotating body 581 to the moving body side rotating body 582 (when the moving unit 550 is stopped at the stop point P), as shown in FIG. The source-side rotating body 581 and the moving-body-side rotating body 582 are arranged to face each other.
Further, in the present embodiment, at this time, the driving source side rotating body 581 and the moving body side rotating body 582 are arranged in a non-contact state.
Here, in the case of non-contact as described above, the displacement of the moving unit 550 due to the contact between the driving source side rotating body 581 and the moving body side rotating body 582 is suppressed, and the image of the image due to the displacement of the moving unit 550 is suppressed. The displacement of the forming position is suppressed.

Further, in the present embodiment, the transmission unit 300 for transmitting the detection result of the phase by the phase detection mechanism 570 to the control unit 900 (see FIG. 1) is provided. The transmission unit 300 is arranged along the movement route R of the movement unit 550. In addition, the transmission unit 300 is configured by a so-called signal rail.
In the present embodiment, a part of the moving unit 550 comes into contact with the transmission unit 300, and the detection result by the phase detection mechanism 570 provided in the moving unit 550 is transmitted to the control unit 900 (see FIG. 1) via the transmission unit 300. ).

More specifically, in the present embodiment, a signal brush 558 that contacts the transmission unit 300 is provided below the pedestal portion 551 of the moving unit 550, and the detection result by the phase detection mechanism 570 is a signal brush 558. 558, and transmitted to the control unit 900 via the transmission unit 300 (signal rail).
The control unit 900 receives the detection result and controls image formation using the inkjet printing unit 700.

FIG. 5 is a diagram when the moving unit 550 and the like are viewed from the direction of the arrow V in FIG.
In the present embodiment, a plurality (a plurality of sets) of transmission units 300 are provided. Specifically, four transmission units 300 of the first transmission unit 310 to the fourth transmission unit 340 are provided.
The four transmission units 300 are arranged side by side in a direction that intersects with the direction in which the movement route R of the movement unit 550 (see also FIG. 4) extends.

Each of the four transmission units 300 is provided with a plurality of signal rails SR.
Here, some signal rails SR of the plurality of signal rails SR are used to supply power to the encoder 571 (see FIG. 4).
Further, some other signal rails SR are for transmitting the detection result by the phase detection mechanism 570 to the control unit 900.

As shown in FIG. 5, the signal brush 558 (see reference numeral 5E) provided on the moving unit 550 stopped at the installation location of the first inkjet head 11C is the first transmission of the four transmission units 300. The part 310 is in contact.
Also, in FIG. 5, a signal brush provided on a moving unit 550 (moving unit 550 indicated by reference numeral 1D in FIG. 1) following one of the moving units 550 (hereinafter, referred to as “preceding moving unit 550”). 558 is also displayed (see reference numeral 5F), and the signal brush 558 comes into contact with the second transmission unit 320 when it reaches the installation location of the first inkjet head 11C.

Further, FIG. 5 also shows a signal brush 558 provided on a moving unit 550 (moving unit 550 shown by reference numeral 1E in FIG. 1) following two units preceding the preceding moving unit 550 (see reference numeral 5G). The signal brush 558 contacts the third transmission unit 330.
FIG. 5 also shows a signal brush 558 provided on a moving unit 550 (moving unit 550 indicated by reference numeral 1F in FIG. 1) following three preceding moving units 550 (see reference numeral 5H). The signal brush 558 contacts the fourth transmission unit 340.

As described above, in the present embodiment, the transmission unit 300 that the signal brush 558 included in each of the moving units 550 contacts is provided for each of the moving units 550.
In addition, in this embodiment, the installation position of the signal brush 558 included in each of the plurality of moving units 550 is different for each moving unit 550. Accordingly, the transmission unit 300 with which the signal brush 558 included in each of the moving units 550 contacts is different for each moving unit 550.

More specifically, in the present embodiment, the installation positions of the signal brushes 558 of each of the moving units 550 are different from each other in a direction intersecting with the moving direction of the moving unit 550 (direction indicated by reference numeral 5X in FIG. 5). ing.
Similarly, the installation positions of the first transmission unit 310 to the fourth transmission unit 340 are different from each other in a direction intersecting the moving direction of the moving unit 550.
Thus, in the present embodiment, the transmission unit 300 with which the signal brush 558 of each of the moving units 550 comes into contact is different for each of the moving units 550.

  Note that the signal brush 558 of each of the moving units 550 also comes into contact with the moving units 550 following the moving unit 550 (moving unit 550 indicated by reference numeral 1G in FIG. 1) following the preceding moving unit 550. The transmitting unit 300 to be performed is different for each mobile unit 550.

  In addition, in this embodiment, in the present embodiment, four types of moving units 550 having different positions for installing the signal brush 558 move on the moving route R in the order of the first to fourth types. Thus, in the present embodiment, at the installation location of the inkjet printing unit 700, the transmission unit 300 that the signal brush 558 of each of the moving units 550 contacts is different for each of the moving units 550.

Here, if there is only one transmitting unit 300 and the transmitting unit 300 that the signal brush 558 of each of the plurality of moving units 550 contacts is the one transmitting unit 300, the control unit 900 The phase of the can 10 in each of the moving units 550 cannot be detected.
In the present embodiment, a different transmitting unit 300 is provided for each moving unit 550, so that the control unit 900 can detect the phase of the can 10 in each moving unit 550.
In addition, at the installation location of the inkjet printing unit 700, only one signal brush 558 is in contact with one transmission unit 300, and thus, for each moving unit 550, the can 10 Phase can be detected.

Further, in the present embodiment, as shown in FIG. 5, a suction mechanism 980 for sucking the can 10 is provided at each stop point P of the moving unit 550 (on the main body side of the printing apparatus 500). The suction mechanism 980 includes a contacted portion 981 with which the moving unit 550 contacts, and a suction pipe 982 connected to the contacted portion 981.
On the other hand, the moving unit 550 is provided with a contact portion 591 that contacts the contacted portion 981, and a connection pipe 592 that connects the contact portion 591 and the support member 20.

In this embodiment, when the moving unit 550 stops at the stop point P, the contact portion 591 comes into contact with the contacted portion 981, and the suction pipe 982 and the connection pipe 592 are connected. Thereby, the can body 10 is sucked, and the can body 10 is urged toward the root side of the support member 20.
In the present embodiment, the positioning of the can 10 in the axial direction of the can 10 is performed by this bias.

Here, the printing process in the inkjet printing unit 700 will be described in detail.
In the present embodiment, when the first inkjet head 11C (see FIG. 1) starts discharging ink (when starting image formation), the control unit 900 transmits the detection result transmitted through the transmission unit 300. , The phase of the can 10 located below the first inkjet head 11 is detected.
In other words, the control unit 900 detects the phase of the can 10 on the moving unit 550 that is stopped below the first inkjet head 11C when starting the ink ejection by the first inkjet head 11C.

In addition, the control unit 900 detects the phase of the can 10 when starting to discharge the ink to the can 10 located below the first inkjet head 11C.
Then, the control unit 900 holds the detected phase. Hereinafter, the held phase is referred to as a “held phase”.

Next, in the present embodiment, the moving unit 550 moves to the second inkjet head 11M, and the ejection of ink by the second inkjet head 11M is started. At this time, the control unit 900 controls the ejection of the ink from the second inkjet head 11M so that the ejection of the ink is started when the phase of the can 10 reaches the above-described holding phase.
The control unit 900 grasps the phase of the can 10 located immediately below the second inkjet head 11M based on the detection result transmitted through the transmission unit 300, and when the phase becomes the holding phase, The discharge of the ink in the second inkjet head 11M is controlled so that the discharge of the ink is started.

  In addition, the control unit 900 controls the ejection of ink from the second inkjet head 11M such that the image formation start position by the first inkjet head 11C and the image formation start position by the second inkjet head 11M are aligned.

More specifically, in the present embodiment, when the ejection of the ink by the second inkjet head 11M is started, the can body 10 is in a state of rotating in the circumferential direction.
The control unit 900 controls the second inkjet head 11M so that the ejection of the ink from the second inkjet head 11M is started when the image formation start position by the first inkjet head 11C reaches immediately below the second inkjet head 11M. 11M is controlled.
This suppresses a shift between the first color image formed by the first inkjet head 11C and the second color image formed by the second inkjet head 11M.

After that, in the present embodiment, the moving unit 550 moves to the third inkjet head 11Y and the fourth inkjet head 11K. At this time, the same processing as described above is executed.
Specifically, the control unit 900 controls the ejection of the ink in the third inkjet head 11Y so that the image formation start position by the first inkjet head 11C and the image formation start position by the third inkjet head 11Y are aligned. .
Further, the control unit 900 controls the ejection of ink by the fourth inkjet head 11K so that the image formation start position by the first inkjet head 11C and the image formation start position by the fourth inkjet head 11K are aligned.
Thus, in the present embodiment, occurrence of a shift between images formed for each color is suppressed.

Here, the phase of the can 10 is changed if the can 10 does not rotate before reaching the next inkjet head 11 after the can 10 has rotated 360 ° below each ink jet head 11. An image can be formed on the can 10 without detection.
In addition, if the can 10 does not rotate before the can 10 reaches the next inkjet head 11 after the can 10 has rotated 360 ° below each inkjet head 11, the The image formation start position is located immediately below the head 11. In this case, an image can be formed on the can 10 without detecting the phase of the can 10.

However, in practice, it is assumed that the can body 10 rotates between the time when the image formation is completed by the inkjet head 11 and the time when the can body 10 reaches the next inkjet head 11. A shift is likely to occur between images to be formed.
On the other hand, when the ejection of ink in each inkjet head 11 is controlled based on the detection result of the phase of the can 10 as in the present embodiment, the occurrence of this shift can be suppressed.

Here, as another aspect, a mechanism for detecting the phase of the can 10 is provided not at the moving unit 550 but at each of the installation positions of the inkjet head 11, for example, each time the moving unit 550 reaches this installation position. The phase of the can 10 can also be detected.
By the way, in this case, since the phase detection is started after the moving unit 550 reaches the installation position, the time until the start of image formation is lengthened, and the printing efficiency is reduced.
On the other hand, in the present embodiment, when the can 10 reaches each of the ink jet heads 11, the detection of the phase of the can 10 ends, so that image formation can be started earlier and printing efficiency can be improved. .

[Others]
In the above description, the moving unit 550 is moved using a so-called linear mechanism. However, the moving of the moving unit 550 is not limited to the linear mechanism. For example, the moving unit 550 is moved to an endless member (a member such as a belt or a chain). May be attached, and the endless member may be moved around.
Further, for example, a driving source such as a motor for moving the moving unit 550 may be provided in each of the moving units 550, and the moving unit 550 may be moved autonomously.

Further, in the above description, the case where the driving source (servo motor M) is provided at the installation position of the inkjet head 11 has been described, but the driving source is the inspection device 92 (see FIG. 1), the light irradiation unit 750, It is also provided in other places such as the protective layer forming portion 770.
In the present embodiment, the rotation of the can body 10 is also performed at other locations by a driving source provided separately from the moving unit 550.

In the above description, the detection result from the mobile unit 550 is output using the transmission unit 300 that comes into contact with the mobile unit 550. However, the output of the detection result (the detection result by the phase detection mechanism 570) from the mobile unit 550 is performed. Is not limited to a contact type, and may be output in a non-contact type such as an output using wireless.
Further, the transmission unit 300 for transmitting the signal output from the mobile unit 550 to the control unit 900 may be provided above the mobile unit 550.

  Although the printing efficiency is lower than the case where the transmission unit 300 is used, a terminal for reading out a detection result by the phase detection mechanism 570 is provided at a location where each inkjet head 11 is installed, and each inkjet head 11 is provided with a terminal. Each time the mobile unit 550 arrives, the detection result may be read.

Further, in the above description, the phase of the can 10 is detected using the encoder 571, but the phase of the can 10 may be detected using another mechanism.
Specifically, for example, an imaging unit such as a CCD (Charge Coupled Device) may be provided in the moving unit 550, and the imaging result of the imaging unit may be analyzed to detect the phase of the can 10.
In this case, an image for detecting the phase of the can body 10 is formed in advance on the outer peripheral surface of the can body 10 by, for example, attaching a scale (an image indicating the scale) to the outer circumferential surface of the can body 10. Is preferred.

DESCRIPTION OF SYMBOLS 10 ... Can body, 300 ... Transmission part, 500 ... Printing device, 550 ... Moving unit, 555 ... Transmission shaft, 558 ... Signal brush, 570 ... Phase detection mechanism, 571A ... Rotating body, 571B ... Rotation center, 581 ... Driving Source side rotating body, 582 ... Moving body side rotating body, 700 ... Inkjet printing unit, M ... Servo motor, R ... Moving path

Claims (12)

Image forming means for forming an image on a can body,
A plurality of moving bodies that support the can body in a rotatable state and move toward the image forming unit,
A detection unit provided on each of the moving bodies, for detecting a phase of the can body;
A printing device comprising:   The printing apparatus according to claim 1, wherein the detection unit detects a phase of the rotating body that rotates in synchronization with rotation of the can body, and detects a phase of the can body. Each of the moving bodies is provided with a transmission shaft for transmitting a rotational driving force to the can body,
The printing apparatus according to claim 2, wherein a rotation center of the rotating body is located at a position off the transmission shaft. The moving body supports a plurality of cans,
The printing apparatus according to claim 1, wherein a phase of each of the plurality of cans is detected by a common detection unit. A drive source for rotating the can body supported by the moving body is provided,
The printing apparatus according to claim 1, wherein the driving source is provided at a location different from the moving body.   The driving force is transmitted from the driving source side rotating body provided on the driving source side to the moving body side rotating body provided on the moving body side, whereby the can body supported by the moving body is The printing device according to claim 5, which rotates.   7. The use of the magnetic force causes the moving body-side rotating body to rotate in synchronization with the driving source-side rotating body, and the driving force is transmitted from the driving source-side rotating body to the moving body-side rotating body. 8. Printing equipment.   The printing according to claim 7, wherein when the driving force is transmitted from the driving source-side rotating body to the moving body-side rotating body, the driving source-side rotating body and the moving body-side rotating body are arranged in a non-contact state. apparatus.   The printing apparatus according to claim 1, further comprising: a transmission unit that is disposed along a movement path of the moving body, a part of the moving body comes into contact, and a transmission unit that transmits a detection result by the detection unit. The transmission unit is provided in plurality,
The printing device according to claim 9, wherein the transmission unit that the part of each of the moving bodies contacts with is provided for each of the moving bodies.   The printing apparatus according to claim 10, wherein the plurality of transmission units are arranged side by side in a direction intersecting a direction in which the moving path of the moving body extends.   The position of the part in each of the plurality of moving bodies in the intersecting direction is different for each of the moving bodies, and the transmitting unit that the part of each of the moving bodies contacts is provided for each of the moving bodies. The printing device according to claim 11, which is different from the above.