JP7091835B2 - Image forming device - Google Patents

Description

The present invention relates to an image forming apparatus, and more particularly to an image forming apparatus in which it is easy to maintain good planar accuracy of an inspection recording medium for forming an inspection image for confirming a ejection state of a recording head. ..

In a so-called single-pass inkjet printer (image forming apparatus), it is required to be able to confirm the ejection state of the recording head in advance without wasting the recording medium (cloth, etc.) that is formed into an image and becomes a product. There is. Since the single-pass inkjet printer forms images at high speed on a large amount of recording media with a large area, an extremely large amount of recording media is wasted if a defect in the ejection state of the recording head is discovered after starting image formation. This is because it becomes.

Therefore, in such an inkjet printer, the inspection recording medium (glossy paper) is conveyed by the inspection second transfer device separately from the first transfer device that conveys the recording medium, and ink is transferred to the inspection recording medium. It has been proposed that the ink is discharged and the discharge state is confirmed (Patent Documents 1 and 2).

Japanese Unexamined Patent Publication No. 2009-241533 Japanese Unexamined Patent Publication No. 2013-208874

In Patent Documents 1 and 2, the second transport device uses a belt having the same width as the first transport device, and has a configuration in which the inspection recording medium having the same width as the width of the recording medium is belt-conveyed. This inspection recording medium is conveyed, and an inspection image is formed by one scan (single pass method) with respect to the recording head. The planar accuracy of the inspection recording medium conveyed by the second transfer device needs to be maintained equal to the planar accuracy of the recording medium conveyed by the first transfer device.

However, in these conventional inkjet printers, the flatness accuracy of the inspection recording medium is required to be the same in both the transport direction and the width direction, and is equivalent to the flatness accuracy of the recording medium conveyed by the first transport device. It was difficult to maintain.

Therefore, an object of the present invention is to provide an image forming apparatus capable of easily maintaining good planar accuracy of an inspection recording medium for forming an inspection image for confirming a ejection state of a recording head. ..

Further, other problems of the present invention will be clarified by the following description.

The above-mentioned problems of the present invention are solved by the following inventions.

1. 1.
The first transport device that transports the recording medium and
A plurality of nozzles, each of which ejects ink to form an image, have a nozzle surface forming an image forming region arranged in a direction intersecting the transport direction of the recording medium by the first transport device, and the nozzle surface is the nozzle surface. A recording head arranged so as to face the surface of the recording medium,
A second transport device for transporting the inspection recording medium in the same direction as the transport direction of the recording medium by the first transport device is provided.
The relative positions of the recording head and the second transport device are changed between the state in which the inspection recording medium faces the nozzle surface and the state in which the inspection recording medium does not face the nozzle surface. It is possible and
In the second transport device, the width in the direction orthogonal to the transport direction of the recording medium is narrower than the width of the image forming region.
In forming an inspection image wider than the inspection recording medium with respect to the inspection recording medium, the recording head divides the inspection image into a plurality of times in the width direction of the inspection recording medium. An image forming apparatus characterized by forming the image.
2. 2.
The image forming apparatus according to 1 above, wherein the image for inspection is formed on the recording medium for inspection while the recording medium for inspection is conveyed by the second conveying apparatus.
3. 3.
The image forming apparatus according to 1 or 2, wherein the change of the relative positions of the recording head and the second transport device with respect to each other is performed by a drive device for moving and operating the second transport device.
4.
The image forming apparatus according to 1 or 2, wherein the change of the relative positions of the recording head and the second transport device with respect to each other is performed by a driving device for moving and operating the recording head.
5.
The image forming apparatus according to any one of 1 to 4, wherein the driving device is held by a skeleton portion that holds the load of the entire image forming apparatus.
6.
An inspection device for capturing an inspection image formed on the inspection recording medium is provided.
5. The image forming apparatus according to 5, wherein the inspection device is held by the skeleton portion.
7.
An inspection device for capturing an inspection image formed on the inspection recording medium is provided.
The image forming apparatus according to any one of 1 to 5, wherein the inspection device is held by the second transport device.
8.
Any of the above 1 to 7, wherein the position relative to the recording head can be changed, the maintenance unit for maintaining the nozzle surface of the recording head is provided, and the maintenance unit is moved and operated by the drive device. The image forming apparatus described in Crab.

INDUSTRIAL APPLICABILITY According to the present invention, it is possible to provide an image forming apparatus in which it is easy to maintain good planar accuracy of an inspection recording medium for forming an inspection image for confirming a ejection state of a recording head.

Schematic side view showing an image forming apparatus according to an embodiment of the present invention. Schematic side view showing the main part of the image forming apparatus Schematic perspective view showing the second transfer device of the image forming apparatus. Schematic perspective view showing the main part of the image forming apparatus Schematic plan view showing the second transfer device of the image forming apparatus Block diagram showing the image forming apparatus Plan view showing an example of an inspection image A plan view showing an example of an inspection image formed on an inspection recording medium by the image forming apparatus. A plan view showing the position of the second transport device before forming an inspection image in the image forming device. A plan view showing the position of the second transport device when the formation of the inspection image is started in the image forming device. A plan view showing the position of the second transport device when forming an inspection image in the image forming device. A plan view showing the position of the second transport device when the formation of the inspection image is completed in the image forming device.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a schematic side view showing an image forming apparatus according to an embodiment of the present invention.

As shown in FIG. 1, this image forming apparatus includes a first transport device 1. The first transport device 1 is a device that adheres the recording medium 101 to maintain flatness and transports the recording medium 101 so that the recording head 2 can form an image on the recording medium 101. The recording medium 101 is various types of paper, cloth, synthetic resin sheet, metal foil, or the like, and an image can be formed by the recording head 2 on the surface thereof (upper side in FIG. 1). In this embodiment, the recording medium 101 is assumed to be a cloth.

In this embodiment, a long (roll) sheet is used as the recording medium 101, but a single-wafer sheet may be used. In this embodiment, the recording head 2 is an inkjet recording head that is fixedly arranged during image formation, and constitutes a so-called single-pass type inkjet recording device 3 as an image forming device. The inkjet recording device 3 includes a first transport device 1 and a recording head 2 that forms an image.

The recording head 2 is composed of a total of 6 colors including a yellow recording head for yellow ink, a magenta recording head for magenta ink, and a cyan recording head for cyan ink, and each print unit has 3 single color heads 2a. However, the number of monochromatic heads 2a is not limited to this, and can be increased or decreased as appropriate.

One monochromatic head 2a is composed of a plurality of heads arranged in the transport direction of the recording medium 101 indicated by the arrow A in FIG. 1 and in the width direction orthogonal to the transport direction. The heads constituting the monochromatic heads 2a form an image forming region 9 in which a plurality of nozzles, each of which ejects ink to form an image, are arranged in a direction intersecting the conveying direction of the recording medium 101 by the first conveying device 1. It has a nozzle surface to form, and the nozzle surface is arranged so as to face the surface of the recording medium 101.

The first transfer device 1 includes an adhesive belt 4 for adhering the recording medium 101. The adhesive belt 4 is an endless belt made of a flexible material such as rubber or synthetic resin. The adhesive belt 4 is moved while the recording medium 101 is adhered to the adhesive belt 4, and as shown by an arrow A in FIG. 1, the adhesive recording medium 101 is conveyed.

The adhesive belt 4 is wound around a plurality of rollers 5, 6, 7, and 8. At least one of these rollers 5, 6, 7, and 8 is a drive roller that is rotationally operated by the drive force of the drive motor. The adhesive belt 4 is moved (feeded) at a predetermined speed by rotating the drive roller. The transport speed of the recording medium 101 is not particularly limited.

In the adhesive belt 4, a portion extending between the two rollers 5 and 6 passes through an image forming region 9 in which the recording medium 101 is held in a plane and an image can be formed by the recording head 2.

The recording medium 101 unwound from the roll body 101a is supplied to the adhesive belt 4 by the supply mechanism 10. The recording medium 101 is carried into the image forming region 9 from the upstream side in the feeding direction of the adhesive belt 4. Further, the recording medium 101 is carried out from the image forming region 9 to the downstream side in the feeding direction of the adhesive belt 4. The recording medium 101 is discharged from the adhesive belt 4 away from the image forming region 9 by a discharge mechanism (not shown).

In the image forming region 9, a roller (not shown) for supporting the adhesive belt 4 is provided directly under the recording head 2 on the back surface (lower side in FIG. 1) of the adhesive belt 4. The back surface of the adhesive belt 4 is supported to maintain flatness.

FIG. 2 is a schematic side view showing a main part of the image forming apparatus.
FIG. 3 is a schematic perspective view showing a second transport device of the image forming device.

As shown in FIG. 2, the inkjet recording device 3 includes a second transport device 11. The second transport device 11 transports the inspection recording medium 13 for forming a test chart for determining the ejection state of each monochromatic head 2a. As shown in FIG. 3, the second transfer device 11 includes a transfer belt 12 on which the inspection recording medium 13 is placed. Examples of the inspection recording medium 13 include glossy paper and cloth. The transport belt 12 is an endless belt made of a flexible material such as rubber or synthetic resin. The transport belt 12 is moved and operated with the inspection recording medium 13 mounted, thereby transporting the mounted inspection recording medium 13 as shown by an arrow B in FIG. The inspection recording medium 13 conveyed by the second transfer device 11 is conveyed in the same direction as the transfer direction of the recording medium 101 by the first transfer device 1.

The width of the second transport device 11 in the direction orthogonal to the transport direction of the recording medium 101 is narrower than the width of the image forming region 9. Further, in the second transport device 11, it is preferable that the length of the recording medium 101 in the transport direction is shorter than the length of the recording medium 101. Further, it is preferable that the width of the inspection recording medium 13 in the direction orthogonal to the transport direction is narrower than the width of the recording medium 101 conveyed by the first transfer device 1.

The inspection recording medium 13 needs to be maintained with the same planar accuracy as the recording medium 101 conveyed by the first transfer device 1. Since a test chart for determining the ejection status of each monochromatic head 2a is formed on the inspection recording medium 13, the plane accuracy must be maintained at the same level as that of the recording medium 101 conveyed by the first transfer device 1. This is because the discharge status cannot be determined correctly.

The transport belt 12 is wound around a plurality of rollers 14 and 15. These rollers 14 and 15 are rotatably supported by a support frame 16 with their axes parallel to each other. One of these rollers 14 and 15 is a drive roller that is rotationally operated by the drive force of the drive motor. The transport belt 12 is moved (feeded) at a predetermined speed by rotating the drive roller. The transport speed of the inspection recording medium 13 is not particularly limited.

As shown in FIG. 2, the second transfer device 11 is inserted between the first transfer device 1 and the recording head 2. When the second transfer device 11 is inserted, the recording head 2 is moved upward so that the first transfer device 1 and the recording head 2 are separated from each other by a distance at which the second transfer device 11 can be inserted. It has become.

In the transport belt 12 of the second transport device 11, a portion extending between the rollers 14 and 15 passes through an image forming region 9 in which the inspection recording medium 13 is held in a plane and an image can be formed by the recording head 2. ..

In the inkjet recording device 3, since the width of the second transport device 11 is narrower than the width of the image forming region 9, it is easy to maintain good planar accuracy of the inspection recording medium 13. Since the width of the recording medium 101 is wide, it is not easy to maintain the planar accuracy of the recording medium 101 within the desired accuracy, but the first transport device 1 is configured to maintain the planar accuracy within the desired accuracy. .. On the other hand, since the width of the second transport device 11 is narrow, the accuracy required for the rollers 14, 15 and the like is lower than that of the first transport device 1, so that the flat surface accuracy of the inspection recording medium 13 is sufficient. Is easy to maintain.

Even if the width of the inspection recording medium 13 is narrowed without narrowing the width of the second transport device 11, the inspection recording medium 13 is less susceptible to the error in the plane accuracy of the second transport device 11. It becomes easy to maintain the plane accuracy of.

FIG. 4 is a schematic perspective view showing a main part of the image forming apparatus.
FIG. 5 is a schematic plan view showing a second transport device of the image forming device.

As shown in FIGS. 4 and 5, the recording head 2 and the second transport device 11 have a state in which the inspection recording medium 13 faces the nozzle surface of the recording head 2 (a state in which an image is formed on the inspection recording medium 13). ) And the state in which the inspection recording medium 13 does not face the nozzle surface (the state in which the inspection recording medium 13 does not form an image), the relative positions of the inspection recording media 13 can be changed.

In this embodiment, the relative positions of the recording head 2 and the second transport device 11 are changed by a drive device (not shown) that moves and operates the second transport device 11, as shown by an arrow C in FIG. The second transport device 11 is moved in a direction intersecting the transport direction of the 101. However, this may be performed by moving the recording head 2 in a direction intersecting the transport direction of the recording medium 101 by a driving device that moves the recording head 2.

The driving device that changes the relative positions of the recording head 2 and the second transport device 11 with respect to each other is preferably held by a skeleton portion that holds the load of the entire inkjet recording device 3.

As shown in FIG. 5, the inkjet recording device 3 preferably includes an inspection device 17 for capturing an inspection image formed on the inspection recording medium 13. It is preferable that the inspection device 17 includes an image pickup camera, an image processing circuit, and the like, and is held by a skeleton portion so that the second transfer device 11 can be inspected in the retracted state. The inspection device 17 may be held by the second transfer device 11.

The inkjet recording device 3 preferably includes a maintenance unit 18. The second transfer device 11 may be arranged as a part of the maintenance unit 18. The maintenance unit 18 is composed of a cleaning unit 19 for maintaining the nozzle surface of the recording head 2, a defect detection unit 20, and a second transfer device 11, and the relative positions of these units with respect to the recording head 2 can be changed integrally. ..

In this embodiment, the maintenance unit 18 and the recording head 2 are changed in relative positions to each other by a second drive device (not shown) for moving and operating the maintenance unit 18, as shown by an arrow D in FIG. The maintenance unit 18 is moved in a direction intersecting the transport direction. However, this may be performed by moving the recording head 2 in a direction intersecting the transport direction of the recording medium 101 by a driving device that moves the recording head 2.

The maintenance unit 18 is movably supported by a guide portion (guide rail) 21, and is moved and operated along the guide portion 21. When the guide unit 21 is configured to move the recording head 2 or the second transport device 11, it is preferable to guide the move operation of the recording head 2 or the second transport device 11.

FIG. 6 is a block diagram showing the image forming apparatus.

As shown in FIG. 6, the inkjet recording device 3 preferably includes a control circuit 22. The control circuit 22 controls the recording head 2 based on the data stored in the memory 23. Further, the control circuit 22 controls the first transfer device 1. That is, the control circuit 22 controls the drive motor that is the drive source for the movement operation (feed operation) of the adhesive belt 4 and the supply operation in the supply mechanism 10. Further, the control circuit 22 controls the second transfer device 11. That is, the control circuit 22 controls the drive motor that is the drive source for the movement operation (feed operation) of the transfer belt 12 and the drive device that moves and operates the second transfer device 11.

FIG. 7 is a plan view showing an example of an inspection image.

In the inkjet recording device 3, as shown in FIG. 7, the recording head 2 has an image forming region 9 having a width wider than that of the inspection recording medium 13 and the second transfer device 11 with respect to the inspection recording medium 13. The inspection image 24 is formed over the width. FIG. 7A shows a part of the inspection image 24, and FIG. 7B shows a part of the inspection image 24 in an enlarged manner. The inspection image 24 is a test chart composed of a thin line pattern or the like, and is formed by forming an image with a number for identifying the head at a different place on the inspection recording medium 13 for each head constituting each monochromatic head 2a. The ejection status of the head can be determined individually. By inspecting each part of the inspection image 24 formed on the inspection recording medium 13, the ejection state of each head can be individually determined.

FIG. 8 is a plan view showing an example of an inspection image formed on an inspection recording medium by the image forming apparatus.

When forming the inspection image 24 on the inspection recording medium 13, the recording head 2 forms the inspection image 24 in a plurality of time divisions in the width direction of the recording medium 101, as shown in FIG. That is, since the inspection image 24 is wider than the inspection recording medium 13, the entire inspection image 24 cannot be formed on the inspection recording medium 13 at one time. Therefore, only the portion of the inspection image 24 corresponding to the position and width of the inspection recording medium 13 is first formed on the inspection recording medium 13, and then the inspection recording medium 13 is formed in the width direction of the recording medium 101. In addition to being moved to, a portion corresponding to the position and width of the inspection recording medium 13 at this time is formed on the inspection recording medium 13 by a feed operation by the second transfer device 11. By forming the inspection image 24 in a time-division manner in this way, the entire inspection image 24 can be formed on the inspection recording medium 13.

In this embodiment, as shown in FIG. 5A, the heads constituting the monochromatic heads 2a are the first head, the third head, the fifth head, and the odd-numbered heads are the widths of the recording medium 101. The second head, the fourth head, the sixth head, and the even-numbered heads are arranged in the direction, and the even-numbered heads are arranged in the width direction of the recording medium 101 at different positions from the odd-numbered heads. The odd-numbered head and the even-numbered head have different positions in both the width direction and the transport direction of the recording medium 101.

In the output example 1 shown in FIG. 8A, after image formation is performed by the first head and the second head, the inspection recording medium 13 is moved in the width direction and fed by the second transport device 11 to perform 3 The image is formed by the No. 5 head and the No. 4 head, and further, the inspection recording medium 13 is moved in the width direction and fed by the second transport device 11, and the image is formed by the No. 5 head and the No. 6 head. The image was formed in. In this case, the images formed by the odd-numbered heads are arranged in the transport direction of the inspection recording medium 13, and the images formed by the even-numbered heads are arranged in the transport direction of the inspection recording medium 13 at different positions. It becomes an image.

In the output example 2 shown in FIG. 8B, after image formation is performed by the first head and the second head, the inspection recording medium 13 is moved in the width direction and fed by the second transport device 11 to perform 3 The image is formed by the No. 2 head and the No. 4 head, and the image formed by the No. 2 head and the image formed by the No. 3 head are formed so as to partially overlap each other. The same applies to the subsequent image formation by the 5th head and the 6th head. In this case, the images formed by the odd-numbered heads are arranged in the transport direction of the inspection recording medium 13, and the images formed by the even-numbered heads partially overlap at positions different from these, and the inspection recording medium is partially duplicated. The images are arranged in the transport direction of 13.

The formation of the inspection image on the inspection recording medium 13 can also be performed while the inspection recording medium 13 is conveyed by the second transfer device 11. In the output example 3 shown in FIG. 8C, the image is formed while the inspection recording medium 13 is conveyed, and the order of image formation is the same as that of the output example 1, but the ejection in each head is performed. An image corresponding to the relative movement locus between the order and the transport of the inspection recording medium 13 is formed.

In any of these output examples, the inspection image 24 is time-divisioned so that the entire inspection image 24 is formed on the inspection recording medium 13.

Hereinafter, how to move the second transfer device 11 when forming the inspection image 24 of the output example 2 will be described. FIG. 9 is a plan view showing the position of the second transport device before forming the inspection image in the image forming device.

In the inkjet recording device 3, as shown in FIG. 9A, before forming the inspection image 24, the second transport device 11 is placed at a position not facing the recording head 2 (outside the image forming region 9). It is in. Next, when the formation of the inspection image 24 is started, the second transfer device 11 is attached to a part of the recording head 2 (the region including the first head and the second head) as shown in FIG. 9B. It is moved to a position (inside the image forming region 9) where the inspection recording medium 13 faces each other.

FIG. 10 is a plan view showing the position of the second transport device when the formation of the inspection image is started in the image forming device.

When the formation of the inspection image 24 is started, as shown in FIG. 10A, ink is ejected from a part (first head, second head) of the recording head 2 facing the inspection recording medium 13. By transporting the inspection recording medium 13 while allowing the inspection recording medium 13, a part of the inspection image 24 is formed on the inspection recording medium 13. After that, as shown in FIG. 10B, the second transport device 11 is at a position (image formation) in which the inspection recording medium 13 faces a part of the recording head 2 (the area including the 3rd head and the 4th head). It is moved to the area 9). Then, a part of the inspection image 24 is formed on the inspection recording medium 13 by a part of the recording head 2 (the third head and the fourth head) on which the inspection recording medium 13 faces.

FIG. 11 is a plan view showing the position of the second transport device when the image forming device is forming an inspection image.

Next, as shown in FIG. 11A, the inspection recording medium 13 is fed and operated, and as shown in FIG. 11B, the second transport device 11 is a part of the recording head 2 (head 5). , The area including the 6th head) is moved to a position (inside the image forming area 9) where the inspection recording medium 13 faces. Then, a part of the inspection image 24 is formed on the inspection recording medium 13 by a part of the recording heads 2 (heads 5 and 6) on which the inspection recording medium 13 faces.

FIG. 12 is a plan view showing the position of the second transport device when the formation of the inspection image is completed in the image forming device.

Next, as shown in FIG. 12 (a), after the formation of the inspection image 24 is completed, as shown in FIG. 12 (b), the second transport device 11 is placed at a position not facing the recording head 2 (image formation). Moved out of region 9). The entire formation of the inspection image 24 is completed by all the heads (heads 1 to 6) on the inspection recording medium 13.

Next, the ejection state of the recording head is confirmed by visually or imaging the inspection image 24 with the inspection device 17, and the result is fed back to the image formation of the product to prevent defects during image formation.

The present invention is not limited to the above-described embodiments, and various improvements and design changes may be made without departing from the spirit of the present invention. Of course, the specific detailed structure and numerical values can be changed as appropriate. In addition, each of the embodiments disclosed this time should be considered to be exemplary and not restrictive in all respects. The scope of the present invention is shown by the scope of claims rather than the above description, and is intended to include all modifications within the meaning and scope equivalent to the scope of claims.

1 1st transport device 2 Recording head 3 Inkjet recording device 4 Adhesive belt 5, 6, 7, 8 Roller 9 Image formation area 10 Supply mechanism 11 2nd transport device 12 Conveyor belt 13 Inspection recording medium 14 Roller 15 Roller 16 Support Frame 17 Inspection device 18 Maintenance unit 19 Cleaning unit 20 Defect detection unit 21 Guide section (guide rail)
22 Control circuit 23 Memory 24 Inspection image 101 Recording medium

Claims (8)

The first transport device that transports the recording medium and
A plurality of nozzles, each of which ejects ink to form an image, have a nozzle surface forming an image forming region arranged in a direction intersecting the transport direction of the recording medium by the first transport device, and the nozzle surface is the nozzle surface. A recording head arranged so as to face the surface of the recording medium,
A second transport device for transporting the inspection recording medium in the same direction as the transport direction of the recording medium by the first transport device is provided.
The relative positions of the recording head and the second transport device are changed between the state in which the inspection recording medium faces the nozzle surface and the state in which the inspection recording medium does not face the nozzle surface. It is possible and
In the second transport device, the width in the direction orthogonal to the transport direction of the recording medium is narrower than the width of the image forming region.
In forming an inspection image wider than the inspection recording medium with respect to the inspection recording medium, the recording head divides the inspection image into a plurality of times in the width direction of the inspection recording medium. An image forming apparatus characterized by forming the image. The image forming apparatus according to claim 1, wherein the inspection image is formed on the inspection recording medium while the inspection recording medium is conveyed by the second conveying apparatus. The image forming apparatus according to claim 1 or 2, wherein the change of the relative positions of the recording head and the second transport device with each other is performed by a drive device for moving and operating the second transport device. The image forming apparatus according to claim 1 or 2, wherein the change of the relative positions of the recording head and the second transport device with each other is performed by a driving device for moving and operating the recording head. The image forming apparatus according to claim 3 or 4, wherein the driving device is held by a skeleton portion that holds the load of the entire image forming apparatus. An inspection device for capturing an inspection image formed on the inspection recording medium is provided.
The image forming apparatus according to claim 5, wherein the inspection apparatus is held by the skeleton portion. An inspection device for capturing an inspection image formed on the inspection recording medium is provided.
The image forming apparatus according to any one of claims 1 to 5, wherein the inspection device is held by the second transport device. 3 . The image forming apparatus according to any one.

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