WO2024202947A1

WO2024202947A1 - Printing device, printing system, and printing method

Info

Publication number: WO2024202947A1
Application number: PCT/JP2024/007910
Authority: WO
Inventors: 勇樹田村
Original assignee: 京セラ株式会社
Priority date: 2023-03-29
Filing date: 2024-03-01
Publication date: 2024-10-03

Abstract

A printing device comprising a conveying member that is capable of conveying a medium positioned on a surface in a conveying direction, an ink head that is capable of causing ink to adhere to the medium, a peeling member that is positioned downstream of the conveying member in the conveying direction and is capable of causing the medium M to peel away from the conveying member, a conveyance drive unit that is capable of driving the conveying member, and a peeling drive unit that is capable of being controlled independently of the conveyance drive unit and is capable of driving the peeling member.

Description

Printing device, printing system, and printing method

The present invention relates to a printing device, a printing system, and a printing method.

Patent Document 1 discloses the application of an inkjet printing device to a textile printing system. The printing device includes a transport belt, which is a transport member for transporting a print medium such as a fabric, and an inkjet head for ejecting ink from above onto the print medium on the transport belt. In the printing device, the print medium is transported in accordance with the circular movement of the transport belt. In the textile printing system, the print medium after printing in the printing device is introduced into a dryer via rollers in the drying section, where the ink is dried. The rollers in the drying section peel off the print medium, which is in close contact with the transport belt of the printing device, from the transport belt and introduce it into the dryer.

JP 2017-226081 A

A printing device according to one aspect of the present invention includes a transport member capable of transporting the print medium located on the surface in a transport direction, an ink unit capable of depositing ink on the print medium, a peeling member located downstream of the transport member in the transport direction and capable of peeling the print medium from the transport member, a transport drive unit capable of driving the transport member, and a peeling drive unit that can be controlled independently of the transport drive unit and can drive the peeling member. With this printing device according to one aspect of the present invention, it is possible to prevent the print medium from being sent downstream while tension is applied due to peeling from the transport member, and it is also possible to adjust the position of the peel start point of the print medium relative to the transport member.

A printing system according to another aspect of the present invention includes the printing device described above, and a drying device into which the print medium peeled off from the transport member by the peeling member in the printing device is introduced and capable of drying the introduced print medium. With this printing system according to another aspect of the present invention, it is possible to prevent the print medium from being sent downstream while tension is being applied due to peeling from the transport member, and it is possible to adjust the position of the peel start point of the print medium relative to the transport member.

A printing method according to another aspect of the present invention includes a transport step of transporting the print medium in a transport direction by a transport member, an ink application step of applying ink to the print medium, and a peeling step of peeling the print medium from the transport member by a peeling member located downstream of the transport member in the transport direction, independently of the transport of the print medium by the transport member. According to the printing method according to this other aspect of the present invention and the printing device according to one aspect of the present invention, it is possible to prevent the print medium from being sent downstream while tension is applied due to peeling from the transport member, and it is possible to adjust the position of the peel start point of the print medium relative to the transport member.

FIG. 1 is a side view showing a schematic configuration of a printing system to which a printing apparatus according to an embodiment of the present invention is applied. FIG. 2 is a side view that illustrates a schematic configuration of the printing apparatus. FIG. 3 is a diagram for explaining the relationship between the transport member and the peeling member in the printing device. FIG. 4 is a timing chart illustrating the operation of the printing device. FIG. 5 is a flowchart showing the process flow of the printing method.

In the above-mentioned conventional textile printing system, when the print medium is peeled off from the conveyor belt by the rollers of the drying section, the print medium may be sent to the dryer downstream in the conveying direction while being subjected to tension caused by peeling off from the conveyor belt. In this case, if the print medium is a fabric, it may be dried in a stretched state, which may cause deformation of the image formed on the print medium and reduce print quality. In addition, when the print medium is peeled off from the conveyor belt by the rollers of the drying section, it is difficult to adjust the position of the peel start point of the print medium relative to the conveyor belt. If the position of the peel start point of the print medium in the area facing upward on the conveyor belt shifts toward the inkjet head, there is a risk that the part of the print medium on which the ink is ejected by the inkjet head will be peeled off from the conveyor belt. On the other hand, if the position of the peel start point of the print medium relative to the conveyor belt reaches the area facing downward on the conveyor belt, it may become impossible to peel off the print medium from the conveyor belt, which may result in poor peeling of the print medium from the conveyor belt.

Therefore, there is a demand for a printing device, printing system, and printing method that can prevent the print medium from being sent downstream while under tension caused by peeling from the transport member, and that can adjust the position of the peel start point of the print medium relative to the transport member.

Below, a printing device, a printing system, and a printing method according to an embodiment of the present invention will be described with reference to the drawings. Note that in the following, directional relationships will be described using XY Cartesian coordinates that are mutually orthogonal on a horizontal plane. Also, the vertical direction perpendicular to the X and Y directions will be referred to as the Z direction.

The printing system 100 shown in FIG. 1 comprises a printing device 1 and a drying device 10. The printing device 1 is a device equipped with an ink unit capable of applying ink to media M, which is a wide and long printing medium. The printing device 1 prints an image by applying ink to the media M using the ink unit. The drying device 10 is positioned downstream of the printing device 1. The drying device 10 is a device capable of drying the media M on which an image has been printed by the printing device 1.

The printing device 1 may be a screen printing device or an inkjet device. When the printing device 1 is a screen printing device, the ink unit includes a screen plate with multiple openings and a squeegee. In this case, the ink unit applies ink to the medium M through the openings in the screen plate by moving the ink along the screen plate in accordance with the movement of the squeegee. On the other hand, when the printing device 1 is an inkjet device, the ink unit applies ink to the medium M by ejecting ink onto the medium M. The case where the printing device 1 is an inkjet device will be described in detail below.

The inkjet printing device 1 is suitable for digital textile printing, which prints images such as letters and patterns on a medium M, which is a cloth member made of fabric such as woven or knitted fabric. The medium M is a long cloth member that extends between the printing device 1 and the drying device 10. The cloth member includes multiple types of fabric with different elasticity. Of course, the printing device 1 can also be used to print various images on printing media such as paper sheets and resin sheets.

As shown in FIG. 1 and FIG. 2, the printing device 1 includes a transport unit 3, a printing unit 4, a peeling member 5, a peeling drive unit 50, a detection unit 6, and a control unit 7.

The transport unit 3 is a unit for transporting the media M in the Y direction. The transport unit 3 has a transport member 31, a first transport roller 32, a second transport roller 33, and a transport drive unit 34.

The transport member 31 is a member capable of transporting media M located on its surface. In this embodiment, the transport member 31 is an endless belt that has a width in the X direction and extends in the Y direction. The transport member 31, which is made of an endless belt, is capable of circular movement. By circular movement along the Y direction, the transport member 31 is capable of transporting media M in contact with the surface of the transport member 31 in a transport direction H1 from one side of the Y direction to the other. An adhesive layer made of an adhesive that adheres the media M is formed on the surface of the transport member 31 in order to hold the media M in contact with the surface of the transport member 31.

The first transport roller 32 is a cylindrical roller extending in the X direction, around which the transport member 31 is wrapped at the most downstream position in the transport direction H1 of the media M on the transport member 31. The first transport roller 32 is rotated in response to the circular movement of the transport member 31. The second transport roller 33 is a cylindrical roller extending in the X direction, around which the transport member 31 is wrapped at the most upstream position in the transport direction H1 of the media M on the transport member 31. The transport member 31 is stretched between the first transport roller 32 and the second transport roller 33 so that the portion of its surface between the first transport roller 32 and the second transport roller 33 is widened in the X and Y directions and horizontal.

The transport drive unit 34 is a drive motor that generates a driving force to rotate the second transport roller 33. The transport drive unit 34 is capable of driving the transport member 31 by driving to rotate the second transport roller 33. In other words, the transport member 31 moves in a circular motion in response to the rotation of the second transport roller 33 driven by the transport drive unit 34, thereby capable of transporting the media M in the transport direction H1 along the Y direction.

The printing unit 4 is a unit for printing an image on the media M in contact with the surface of the transport member 31. The printing unit 4 is a unit in which an inkjet head 42 having an ink head 421, a pretreatment liquid head 422, and a posttreatment liquid head 423 is mounted on a carriage 41. The printing unit 4 is disposed above the transport member 31 in the Z direction. The printing device 1 is a so-called serial printer that performs printing processing on the media M by a serial printing method. In the printing device 1 using the serial printing method, an ejection operation in which various liquids are ejected from the inkjet head 42 while the carriage 41 is moved back and forth in the X direction perpendicular to the Y direction, which is the transport direction H1 of the media M, on the horizontal plane, and an operation of transporting the media M by the transport member 31 are repeatedly performed.

The carriage 41 is fixed to a timing belt 212 that is attached to a flat carriage guide 21 that has a guide rail 211 extending in the X direction. The timing belt 212 is an endless belt that is attached to the carriage guide 21 so that it can move in circles in the X direction. The carriage 41 can move back and forth in the X direction along the carriage guide 21 while being guided by the guide rail 211 as the timing belt 212 moves in circles in the X direction.

Each of the ink head 421, pre-treatment liquid head 422, and post-treatment liquid head 423 included in the inkjet head 42 mounted on the carriage 41 can move in the X and Y directions relative to the media M as the media M is transported in the Y direction by the transport member 31 and the carriage 41 moves back and forth in the X direction. In this case, the X direction indicating the direction in which the carriage 41 moves is the main scanning direction, and the Y direction indicating the transport direction H1 of the media M is the sub-scanning direction.

The carriage 41 is equipped with a plurality of ink heads 421. Each of the ink heads 421 is an ink unit capable of depositing ink containing a coloring material onto the medium M on the transport member 31. Each of the ink heads 421 includes a number of nozzles that eject ink droplets using an ejection method such as a piezo method using a piezo element or a thermal method using a heating element, an ink flow path that guides ink to the nozzles, and a wiring board for controlling the ink ejection operation. The ink heads 421 are mounted on the carriage 41 so as to be aligned in two rows in the X direction. Two ink heads 421 that eject ink of the same color are mounted on the carriage 41 so as to be positioned at mutually offset positions in the X and Y directions. Another embodiment includes a configuration in which one ink head 421 is mounted on the carriage 41.

The pretreatment liquid head 422 is mounted on the carriage 41 so as to be disposed upstream of the ink head 421 in the transport direction H1 of the media M by the transport member 31. The pretreatment liquid head 422 is a pretreatment liquid unit capable of applying the pretreatment liquid to the media M on the transport member 31 before the ink by ejecting the pretreatment liquid. The pretreatment liquid head 422 includes a number of nozzles that eject the pretreatment liquid by an ejection method such as a piezo method using a piezo element or a thermal method using a heating element, a pretreatment liquid flow path that guides the pretreatment liquid to the nozzles, and a wiring board for controlling the ejection operation of the pretreatment liquid. The pretreatment liquid is a treatment liquid that comes into contact with the ink when it is not dried on the media M, and is a non-coloring treatment liquid that does not develop color even when it is attached to the media M. The pretreatment liquid unit that applies the pretreatment liquid to the media M on the transport member 31 is not limited to a head structure such as the pretreatment liquid head 422, and may be a spray type structure that sprays the pretreatment liquid.

The post-treatment liquid head 423 is mounted on the carriage 41 so as to be disposed downstream of the ink head 421 in the transport direction H1 of the media M by the transport member 31. The post-treatment liquid head 423 is a post-treatment liquid unit capable of applying the post-treatment liquid to the media M on the transport member 31 after the ink by ejecting the post-treatment liquid. The post-treatment liquid head 423 includes a number of nozzles that eject the post-treatment liquid by an ejection method such as a piezo method using a piezo element or a thermal method using a heating element, a post-treatment liquid flow path that guides the post-treatment liquid to the nozzles, and a wiring board for controlling the ejection operation of the post-treatment liquid. The post-treatment liquid is a treatment liquid that comes into contact with the ink in a non-dried state on the media M, and is a non-coloring treatment liquid that does not develop color even when attached to the media M. The post-treatment liquid has a function of increasing the fixability of the ink on the media M. As such a post-treatment liquid, a treatment liquid containing silicone oil or the like can be used. The post-processing liquid unit that applies the post-processing liquid to the media M on the transport member 31 is not limited to a head structure such as the post-processing liquid head 423, but may have a spray type structure that sprays the post-processing liquid.

In the printing unit 4, a liquid ejection operation is performed on the media M in contact with the surface of the transport member 31, in which pretreatment liquid is ejected from the pretreatment liquid head 422, ink is ejected from the ink head 421, and, if necessary, posttreatment liquid is ejected from the posttreatment liquid head 423. This causes an image to be printed on the media M. That is, on the media M on the transport member 31, the pretreatment liquid ejected from the pretreatment liquid head 422 adheres to the media M, and then the ink ejected from the ink head 421 adheres to the media M, and then, if necessary, the posttreatment liquid ejected from the posttreatment liquid head 423 adheres to the media M.

The pretreatment liquid ejected from the pretreatment liquid head 422 is a treatment liquid containing an aqueous solvent whose main component is water and a cationic resin that is positively charged. The ink ejected from the ink head 421 is a pigment ink that contains a pigment as a coloring material. The pigment ink is an ink that contains an aqueous medium whose main component is water, a pigment, and a binder resin. The pigment may be an anionic pigment. The anionic pigment electrically reacts and aggregates with the cationic resin contained in the pretreatment liquid ejected from the pretreatment liquid head 422 on the medium M, so that the binder resin contained in the pigment ink can be prevented from penetrating into the medium M. This makes it possible to reduce the penetration of the binder resin into the gaps between the fibers and the binding of the fibers together when the medium M is a cloth material. This makes it possible to improve the texture, such as the feel of the cloth material.

The peeling member 5 is a member located downstream of the conveying member 31 in the conveying direction H1. Specifically, the peeling member 5 is installed at a position above and downstream of the downstream end portion 311 located at the downstream end of the conveying member 31 in the conveying direction H1. The downstream end portion 311 is a portion of the conveying member 31 that is wrapped around the first conveying roller 32. The peeling member 5 is installed so that a portion of the peeling member 5 overlaps with the downstream end portion 311 when viewed in each of the Y direction and the Z direction. The peeling member 5 is located above the extension line of the conveying direction H1 of the media M on the conveying member 31. The peeling member 5 is capable of peeling the media M from the conveying member 31 when in contact with the surface of the conveying member 31. In this embodiment, the peeling member 5 is a cylindrical roller extending in the X direction. The peeling member 5 made of a roller is provided to be rotatable around an axis extending in the X direction.

A predetermined area MM of the media M in the transport direction H1 extending between the printing device 1 and the drying device 10 is wrapped around the outer peripheral surface 5A of the peeling member 5 from the upper side in the Z direction. The media M that is in contact with the surface of the transport member 31 and has the predetermined area MM wrapped around the peeling member 5 is peeled upward from the transport member 31 with the peeling start point MPP as the boundary with respect to the contact portion M1 that is in contact with the surface of the transport member 31. The peeling member 5 rotates with the predetermined area MM of the media M attached to the outer peripheral surface 5A from the upper side, thereby making it possible to peel off from the transport member 31 the portion of the media M that is in contact with the surface of the transport member 31 that is upstream of the predetermined area MM in the transport direction H1. The rotation direction of the peeling member 5 when peeling the media M from the transport member 31 coincides with the rotation direction of the first transport roller 32 when transporting the media M in the transport direction H1 by the circular movement of the transport member 31.

When the media M is wrapped around the outer peripheral surface 5A of the peeling member 5, frictional force is generated between the outer peripheral surface 5A and the portion M21 of the media M that is wrapped around the outer peripheral surface 5A. The peeling member 5 rotates to peel the media M from the conveying member 31 based on the frictional force between the wrapped portion M21 and the outer peripheral surface 5A, and sends the media M downstream toward the drying device 10. In this case, in the peeled portion M2 of the media M peeled from the conveying member 31 by the peeling member 5, tension associated with peeling from the conveying member 31 is applied to the area located between the downstream end portion 311 of the conveying member 31 and the outer peripheral surface 5A of the peeling member 5, but no tension is applied to the area downstream of the peeling member 5. This makes it possible to prevent the media M from being sent downstream while being subjected to tension associated with peeling from the conveying member 31. This prevents the media M introduced into the drying device 10, which is located downstream of the peeling member 5, from being dried in a stretched state, thereby preventing the image formed on the media M from being deformed, which would result in a decrease in print quality.

In addition, the media M peeled off from the transport member 31 by the peeling member 5 is curved downward in the Z direction between the peeling member 5 and the drying device 10 and introduced into the drying device 10. This more reliably prevents the media M introduced into the drying device 10 from being dried in a stretched state.

As shown in FIG. 2, the peeling member 5 has a base 51 and a surface layer 52 that is provided on the base 51 and forms the outer circumferential surface 5A. The surface layer 52 is made of a rubber material. Since the surface layer 52 that forms the outer circumferential surface 5A of the peeling member 5 is made of a rubber material, the frictional force between the outer circumferential surface 5A and the wrapped portion M21 of the media M that wraps around the outer circumferential surface 5A can be increased. This allows the peeling member 5 to more reliably peel the media M from the conveying member 31 based on the frictional force.

The rubber material forming the surface layer 52 of the peeling member 5 may be a foamed rubber material. The surface layer 52 made of a foamed rubber material has a plurality of pores. In this case, even if ink on the media M is transferred to the outer peripheral surface 5A of the peeling member 5 when the media M is wrapped around the outer peripheral surface 5A, the transferred ink can be captured in the pores of the surface layer 52. This makes it possible to prevent the outer peripheral surface 5A from becoming slippery due to the transfer of ink to the outer peripheral surface 5A of the peeling member 5.

Furthermore, a member having an abrasive surface may be used for the surface layer 52 of the peeling member 5. In this case, the abrasive grains are more likely to catch on the media M and are less likely to slip, so the media M can be peeled off more reliably. Sandpaper of #40 to #240 can be used as the abrasive surface, with #100 to #150 being more preferable. An example of a member having an abrasive surface is abrasive paper with adhesive, and the abrasive grains can be silicon carbide grains.

If the position of the peel start point MPP of the media M in contact with the surface of the transport member 31 shifts toward the printing unit 4 in the upward-facing area of the transport member 31, there is a risk that the portion of the media M to be printed by the printing unit 4 will be peeled off from the transport member 31. On the other hand, if the position of the peel start point MPP of the media M in contact with the surface of the transport member 31 reaches the area of the transport member 31 facing downward, it becomes impossible to peel the media M from the transport member 31, and there is a risk that poor peeling of the media M from the transport member 31 will occur. For this reason, it is necessary to adjust the position of the peel start point MPP of the media M in contact with the transport member 31.

As shown in FIG. 3, the position of the peeling start point MPP of the media M relative to the transport member 31 changes in accordance with the circular movement of the transport member 31 and also changes in accordance with the rotation of the peeling member 5. As described above, when the peeling member 5 is installed so that a portion of the peeling member 5 overlaps with the downstream end portion 311 of the transport member 31 when viewed in each of the Y and Z directions, the position of the peeling start point MPP of the media M changes within the range of the downstream end portion 311 wrapped around the first transport roller 32 of the transport member 31. The position of the peeling start point MPP of the media M changes within the range of the downstream end portion 311 to the downstream side in the rotation direction of the first transport roller 32 in accordance with the circular movement of the transport member 31, and changes to the upstream side in the rotation direction of the first transport roller 32 in accordance with the rotation of the peeling member 5.

In view of the above circumstances, by controlling the circular movement of the transport member 31 and the rotation of the peeling member 5, it is possible to adjust the position of the peeling start point MPP of the media M relative to the transport member 31. In this case, if the peeling member 5 is rotated in synchronization with the circular movement of the transport member 31, it is difficult to accurately adjust the position of the peeling start point MPP of the media M.

The printing device 1 according to this embodiment is therefore provided with a peeling drive unit 50 that can be controlled independently of the transport drive unit 34 that moves the transport member 31 in a circular motion and that can drive the peeling member 5. The peeling drive unit 50 is a drive motor that can generate a driving force to rotate the peeling member 5. The peeling drive unit 50 can rotate the peeling member 5 independently of the circular motion of the transport member 31 driven by the transport drive unit 34. This makes it possible to accurately adjust the position of the peeling start point MPP of the media M relative to the transport member 31.

When the position of the peeling start point MPP of the media M relative to the conveying member 31 changes, the peeling angle α of the media M changes, and the winding angle β of the wound portion M21 of the media M wound around the peeling member 5 also changes. The peeling angle α indicates the angle between the peeled portion M2 of the media M that is peeled off from the conveying member 31 and located in the area between the conveying member 31 and the peeling member 5, and the contact portion M1 of the media M that is in contact with the surface of the conveying member 31. The winding angle β is expressed as the central angle of the arc of the wound portion M21 along the outer circumferential surface 5A of the peeling member 5. If the position of the peeling start point MPP of the media M changes downstream in the rotation direction of the first conveying roller 32 in response to the circular movement of the conveying member 31, the peeling angle α becomes smaller and the winding angle β becomes larger. On the other hand, if the position of the peeling start point MPP of the media M changes upstream in the rotation direction of the first conveying roller 32 in response to the rotation of the peeling member 5, the peeling angle α becomes larger and the winding angle β becomes smaller.

In the printing device 1 according to this embodiment, the detection unit 6 is disposed below the peeling member 5. The detection unit 6 is a sensor capable of detecting peeled portion M2 of the media M peeled off from the transport member 31 and located in the area between the transport member 31 and the peeling member 5. The peeled portion M2 of the media M to be detected by the detection unit 6 is a portion of the media M peeled off from the transport member 31 and located in the area between the part of the transport member 31 corresponding to the downstream end of the transport direction H1 of the carriage 41 on which the inkjet head 42 is mounted and the outer peripheral surface 5A of the peeling member 5. In this embodiment, the peeled portion M2 of the media M to be detected by the detection unit 6 is a portion of the media M peeled off from the transport member 31 and located in the area between the downstream end portion 311 wound around the first transport roller 32 of the transport member 31 and the outer peripheral surface 5A of the peeling member 5. The detection unit 6 is, for example, a photoelectric sensor capable of adjusting the detection range 61. The detection unit 6, which is made up of a photoelectric sensor, emits detection light from a light projecting unit and receives the light reflected by the peeled portion M2 of the media M with a light receiving unit, thereby being able to detect the peeled portion M2. The detection unit 6 is capable of adjusting a detection range 61 on the optical path through which the detection light passes.

The detection unit 6 has a detection range 61 set as a predetermined range on the optical path perpendicular to a plane VP extending in the X direction that includes the center 32S of the first transport roller 32 and the center 5S of the peeling member 5 within the area between the downstream end portion 311 of the transport member 31 and the outer circumferential surface 5A of the peeling member 5. The detection unit 6 is in the ON state when the peeled portion M2 of the media M is located within the detection range 61, and is in the OFF state when the peeled portion M2 of the media M is located outside the detection range 61. The detection result of the detection unit 6 is referenced by the control unit 7 described below.

The control unit 7 is a personal computer having a CPU (Central Processing Unit), a storage area such as a HDD (Hard Disk Drive) or flash memory for storing processing programs, and a RAM (Random Access Memory) used as a working area for the CPU. The control unit 7 executes the processing of each step of the printing method using the printing device 1 by the CPU executing the processing programs stored in the HDD or flash memory. The processing of each step of the printing method executed by the control unit 7 will be described with reference to Figures 3, 4, and 5.

The control unit 7 performs each process of the printing process, which includes a pretreatment liquid application process S1, an ink application process S2, and a posttreatment liquid application process S3, a transport process S4, and a peeling process S5.

In the pretreatment liquid application process S1, the control unit 7 performs a pretreatment liquid application process to apply the pretreatment liquid to the media M in contact with the surface of the transport member 31 by ejecting the pretreatment liquid from the pretreatment liquid head 422. In the ink application process S2, the control unit 7 performs an ink application process to apply the ink to the media M in contact with the surface of the transport member 31 by ejecting ink from the ink head 421. In the posttreatment liquid application process S3, the control unit 7 performs a posttreatment liquid application process to apply the posttreatment liquid to the media M in contact with the surface of the transport member 31 by ejecting the posttreatment liquid from the posttreatment liquid head 423. Note that the control unit 7 is not limited to performing the pretreatment liquid application process, the ink application process, and the posttreatment liquid application process. For example, the pretreatment liquid head 422 may perform the pretreatment liquid application process, the ink head 421 may perform the ink application process, and the posttreatment liquid head 423 may perform the posttreatment liquid application process.

In the transport step S4, the control unit 7 performs a transport drive process that drives the transport drive unit 34 in response to each of the deposition processes of the pre-treatment liquid deposition process, the ink deposition process, and the post-treatment liquid deposition process. The control unit 7 moves the transport member 31 in a circular motion in response to the driving of the transport drive unit 34 in the transport drive process, thereby transporting the media M in contact with the surface of the transport member 31 in the transport direction H1. Note that the control unit 7 is not limited to performing the transport drive process. For example, the transport drive process may be performed by the transport drive unit 34.

In the peeling step S5, the control unit 7 performs a peeling drive process that drives the peeling drive unit 50. The control unit 7 rotates the peeling member 5 in response to the driving of the peeling drive unit 50 in the peeling drive process, thereby peeling the media M in contact with the surface of the transport member 31 from the transport member 31. Specifically, the control unit 7 rotates the peeling member 5 in response to the driving of the peeling drive unit 50, independently of the circular movement of the transport member 31 driven by the transport drive unit 34. This makes it possible to accurately adjust the position of the peeling start point MPP of the media M relative to the transport member 31, compared to when the peeling member 5 is rotated in synchronization with the circular movement of the transport member 31.

The pretreatment liquid application process in the pretreatment liquid application process S1, the ink application process in the ink application process S2, the posttreatment liquid application process in the posttreatment liquid application process S3, the transport drive process in the transport process S4, and the peeling drive process in the peeling process S5, which are performed by the control unit 7, will be described in more detail with reference to Figures 3 and 4. In the following description, the ink head 421, the pretreatment liquid head 422, and the posttreatment liquid head 423 will be collectively referred to as the "inkjet head 42", the ink, pretreatment liquid, and posttreatment liquid will be collectively referred to as the "liquid", and the ink application process, pretreatment liquid application process, and posttreatment liquid application process will be collectively referred to as the "liquid application process".

The control unit 7 repeatedly performs a liquid attachment process in which the carriage 41 on which the inkjet head 42 is mounted is moved in the X direction at a predetermined head scanning period HSC to eject liquid from the inkjet head 42, and a transport drive process in which the transport drive unit 34 is driven in response to the liquid attachment process. When the control unit 7 is in the "ON" state in which liquid is ejected from the inkjet head 42 in the liquid attachment process, it sets the transport drive unit 34 to the "OFF" state in which it stops driving the transport drive unit 34 in the transport drive process, and when the control unit 7 is in the "OFF" state in which it stops ejecting liquid from the inkjet head 42 in the liquid attachment process, it sets the transport drive unit 34 to the "ON" state in which it drives the transport drive unit 34 in the transport drive process. In other words, the control unit 7 switches between driving and stopping the transport drive unit 34 in the transport drive process in response to switching between ejecting and stopping ejection of liquid by the inkjet head 42 in the liquid attachment process. The liquid attachment process and the transport drive process are repeatedly performed by the control unit 7, and an image is printed on the media M in contact with the surface of the transport member 31.

The control unit 7 drives the transport drive unit 34 in the transport drive process so that the speed of the circular movement of the transport member 31 in response to the drive of the transport drive unit 34 becomes a predetermined transport movement speed VB, and the movement distance of the circular movement of the transport member 31 in response to the drive of the transport drive unit 34 becomes a predetermined transport movement distance DB. As a result, the media M in contact with the surface of the transport member 31 is transported in the transport direction H1 by a transport length equivalent to the transport movement distance DB of the transport member 31 at a transport speed equivalent to the transport movement speed VB of the transport member 31 with each transport drive process by the control unit 7.

When a predetermined region MM of the media M is wrapped around the outer peripheral surface 5A of the peeling member 5 from above on the downstream side of the conveying direction H1 relative to the conveying member 31, the position of the peeling start point MPP of the media M relative to the conveying member 31 changes downstream in the rotation direction of the first conveying roller 32 in accordance with the circular movement of the conveying member 31, within the range of the downstream end portion 311 wrapped around the first conveying roller 32 of the conveying member 31. When the position of the peeling start point MPP of the media M changes downstream in the rotation direction of the first conveying roller 32, the peeling angle α of the media M changes to become smaller, and the winding angle β of the wound portion M21 of the media M wound around the peeling member 5 changes to become larger.

The detection unit 6 is turned ON when the peeling angle α between the contact portion M1 and the peeling portion M2 of the media M is less than 90 degrees and the peeling portion M2 is located within the detection range 61. In this case, the position of the peeling start point MPP of the media M changes downstream in the rotation direction of the first conveying roller 32 in accordance with the rotational movement of the conveying member 31, and the detection unit 6 is turned ON when the peeling angle α decreases to less than 90 degrees. In other words, the first sensor switching timing TS1 indicating the timing when the detection unit 6 switches from the OFF state to the ON state coincides with the timing when the peeling angle α of the media M becomes less than 90 degrees. When the peeling angle α of the media M is less than 90 degrees, the winding angle β of the wrapped portion M21 of the media M with respect to the peeling member 5 is large enough that the frictional force between the outer circumferential surface 5A of the peeling member 5 and the wrapped portion M21 is large enough to peel the media M from the conveying member 31.

The control unit 7 performs a peeling drive process for driving the peeling drive unit 50 in response to detection by the detection unit 6 for each transport drive process. When the detection unit 6 is ON during the peeling drive process, the control unit 7 sets the peeling drive unit 50 to an "ON" state, which drives the peeling drive unit 50. At this time, the control unit 7 drives the peeling drive unit 50 so that the peeling member 5 rotates at a predetermined circumferential speed VR in response to the drive of the peeling drive unit 50, and the movement distance along the rotational direction of the outer circumferential surface 5A of the peeling member 5 in response to the drive of the peeling drive unit 50 is a predetermined rotational movement distance DR. As a result, the media M in contact with the surface of the transport member 31 is peeled off at a peeling speed equivalent to the circumferential speed VR of the peeling member 5, by a peeling length equivalent to the rotational movement distance DR of the peeling member 5.

The position of the peeling start point MPP of the media M relative to the transport member 31 changes upstream in the rotation direction of the first transport roller 32 in response to the rotation of the peeling member 5, within the range of the downstream end portion 311 wrapped around the first transport roller 32 of the transport member 31. When the position of the peeling start point MPP of the media M changes upstream in the rotation direction of the first transport roller 32, the peeling angle α of the media M changes to become larger, and the winding angle β of the wound portion M21 of the media M wrapped around the peeling member 5 changes to become smaller.

When the position of the peeling start point MPP of the media M changes upstream in the rotation direction of the first transport roller 32 in response to the rotation of the peeling member 5 and the peeling angle α increases to 90 degrees or more, the peeled portion M2 of the media M is positioned outside the detection range 61 and the detection unit 6 is turned OFF. In other words, the second sensor switching timing TS2, which indicates the timing at which the detection unit 6 switches from the ON state to the OFF state, coincides with the timing at which the peeling angle α of the media M changes from less than 90 degrees to 90 degrees or more. When the detection unit 6 is OFF during the peeling drive process, the control unit 7 switches the peeling drive unit 50 to the "OFF" state, which stops the drive of the peeling drive unit 50.

As described above, the control unit 7 drives the peeling drive unit 50 in response to detection by the detection unit 6, thereby rotating the peeling member 5 independently of the circular movement of the transport member 31 driven by the transport drive unit 34. This makes it possible to prevent the media M from being sent downstream with tension applied thereto due to peeling from the transport member 31 when the media M is peeled from the transport member 31 in response to the rotation of the peeling member 5, and to accurately adjust the position of the peeling start point MPP of the media M relative to the transport member 31. This prevents the media M introduced into the drying device 10 arranged downstream of the peeling member 5 from being dried in a stretched state, prevents the portion of the media M to which the liquid is to be applied by the inkjet head 42 from being peeled from the transport member 31, and prevents poor peeling of the media M from the transport member 31.

In addition, in the peeling drive process, the control unit 7 switches the drive of the peeling drive unit 50 from a stopped state to a driven state after a predetermined first delay time DT1 has elapsed from the first sensor switching timing TS1 at which the detection unit 6 switches from an OFF state to an ON state. That is, the control unit 7 switches the drive of the peeling drive unit 50 from a stopped state to a driven state at the first drive switching timing TM1 after the first delay time DT1 has elapsed from the first sensor switching timing TS1. In addition, in the peeling drive process, the control unit 7 switches the drive of the peeling drive unit 50 from a driven state to a stopped state after a predetermined second delay time DT2 has elapsed from the second sensor switching timing TS2 at which the detection unit 6 switches from an ON state to an OFF state. That is, the control unit 7 switches the drive of the peeling drive unit 50 from a driven state to a stopped state at the second drive switching timing TM2 after the second delay time DT2 has elapsed from the second sensor switching timing TS2. By setting the first and second drive switching timings TM1 and TM2 to the timings after the first and second delay times DT1 and DT2 have elapsed for the first and second sensor switching timings TS1 and TS2, respectively, it is possible to prevent the occurrence of a chattering phenomenon in which the ON and OFF states of the detection unit 6 are repeatedly switched at high speed. This makes it possible to prevent the occurrence of a phenomenon in which the peeling drive unit 50 abnormally repeats a driven state and a stopped state due to chattering of the detection unit 6.

In addition, in the peeling drive process, the control unit 7 drives the peeling drive unit 50 so that the rotational movement distance DR of the peeling member 5 falls within a predetermined tolerance range based on the transport movement distance DB of the transport member 31. For example, the lower limit of the tolerance range is set to the same value as the transport movement distance DB, and the upper limit of the tolerance range is set to a value twice the transport movement distance DB. That is, the control unit 7 drives the peeling drive unit 50 so that the rotational movement distance DR of the peeling member 5 is equal to or greater than the transport movement distance DB and equal to or less than twice the transport movement distance DB (DB≦DR≦2DB) in response to the detection unit 6 being in the ON state. By driving the peeling drive unit 50 so that the rotational movement distance DR of the peeling member 5 is equal to or greater than the transport movement distance DB, it is possible to prevent the position of the peeling start point MPP of the media M relative to the transport member 31 from being too far downstream in the rotation direction of the first transport roller 32 when the media M is peeled off from the transport member 31 in response to the rotation of the peeling member 5 driven by the peeling drive unit 50. This prevents the printed surfaces of the contact portion M1 and the peeled portion M2 of the media M from coming into contact with each other between the downstream end portion 311 of the transport member 31 and the outer peripheral surface 5A of the peeling member 5. On the other hand, by driving the peeling drive unit 50 so that the rotational movement distance DR of the peeling member 5 is less than twice the transport movement distance DB, it is possible to prevent the position of the peeling start point MPP of the media M relative to the transport member 31 from being too far upstream in the rotation direction of the first transport roller 32 when the media M is peeled off from the transport member 31 in response to the rotation of the peeling member 5 driven by the peeling drive unit 50. This prevents the portion of the media M to which the liquid is to be applied by the inkjet head 42 from being peeled off from the transport member 31.

In addition, in the peeling drive process, the control unit 7 drives the peeling drive unit 50 so that the peripheral speed VR of the rotation of the peeling member 5 in response to the drive of the peeling drive unit 50 is equal to or lower than the transport movement speed VB of the circular movement of the transport member 31 in response to the drive of the transport drive unit 34 (VR≦VB). This makes it possible to prevent the position of the peeling start point MPP of the media M relative to the transport member 31 from being too far upstream in the rotation direction of the first transport roller 32 when the media M is peeled from the transport member 31 in response to the rotation of the peeling member 5 driven by the peeling drive unit 50. This more reliably prevents the portion of the media M to which liquid is to be applied by the inkjet head 42 from being peeled off from the transport member 31.

In addition, in the peeling drive process, the control unit 7 outputs error information if the detection unit 6 remains ON even after a time equivalent to the head scanning period HSC has elapsed since the control unit 7 started driving the peeling drive unit 50 in response to the first sensor switching timing TS1 at which the detection unit 6 switches from the OFF state to the ON state. If the detection unit 6 remains ON even though the peeling member 5 is rotating in response to the drive of the peeling drive unit 50, it may become impossible to peel the media M from the transport member 31, and a peeling failure of the media M from the transport member 31 may occur. For this reason, the control unit 7 outputs error information. In response to the output of the error information, the control unit 7 may display the error information on a display or other display unit, or may stop the printing device 1. This allows the operator of the printing device 1 to take measures to improve the peeling failure of the media M from the transport member 31.

REFERENCE SIGNS LIST 1 Printing device 3 Transport unit 31 Transport member 34 Transport drive unit 4 Printing unit 42 Inkjet head 421 Ink head (ink unit)
5 Peeling member 50 Peeling drive unit 51 Base body 52 Surface layer 6 Detection unit 61 Detection range 7 Control unit 10 Drying device 100 Printing system M Media (printing medium)

Claims

a conveying member capable of conveying a print medium located on a surface thereof in a conveying direction;
an inking unit capable of depositing ink onto the print medium;
a peeling member that is located downstream of the transport member in the transport direction and that is capable of peeling the print medium from the transport member;
A transport drive unit capable of driving the transport member;
a peeling drive unit that can be controlled independently of the transport drive unit and that can drive the peeling member.
The printing device according to claim 1, wherein the peeling member is rotatably arranged with a predetermined area of the print medium in the transport direction attached thereto, and is capable of peeling off a portion of the print medium upstream of the predetermined area in the transport direction from the transport member in response to the rotation.
a detection unit capable of detecting a peeled portion of the print medium that has been peeled off from the transport member and is located in a region between the transport member and the peeling member;
The printing device according to claim 2, further comprising a control unit that performs an ink adhesion process in which the ink unit adheres the ink to the printing medium, a transport drive process in which the transport drive unit is driven in response to the ink adhesion process, and a peeling drive process in which the peeling drive unit is driven in response to detection by the detection unit.
the detection unit is turned on when the peeled portion is located within a detection range set in an area between the transport member and the peeling member, and is turned off when the peeled portion is located outside the detection range,
The printing apparatus according to claim 3 , wherein the control unit drives the peeling drive unit when the control unit is in the ON state, and stops driving the peeling drive unit when the control unit is in the OFF state, in the peeling drive process.
The printing device according to claim 4, wherein the detection unit is in the ON state when the peeled portion is located within the detection range and the angle between the contact portion of the print medium that contacts the surface of the transport member and the peeled portion is less than 90 degrees.
The printing device according to claim 4 or 5, wherein the control unit switches between driving and stopping the peeling drive unit after a predetermined delay time has elapsed from the timing at which the detection unit switches between the ON state and the OFF state during the peeling drive process.
The printing device according to any one of claims 4 to 6, wherein the control unit drives the peeling drive unit in the peeling drive process so that the rotational movement distance of the outer peripheral surface of the peeling member in response to the drive of the peeling drive unit falls within a predetermined allowable range based on the transport movement distance of the transport member in response to the drive of the transport drive unit in the transport drive process.
The printing device according to any one of claims 4 to 7, wherein the control unit drives the peeling drive unit in the peeling drive process so that the peripheral speed of rotation of the peeling member in response to the drive of the peeling drive unit is equal to or lower than the transport movement speed of the transport member in response to the drive of the transport drive unit in the transport drive process.
The printing device according to any one of claims 2 to 8, wherein the peeling member has a base and a surface layer made of a rubber material provided on the base.
The printing device according to claim 9, wherein the surface layer has a plurality of pores.
The printing device according to any one of claims 1 to 10, wherein the printing medium is a cloth member made of fabric.
A printing device according to any one of claims 1 to 11,
a drying device capable of drying the print medium peeled off from the transport member by the peeling member in the printing device.
a conveying step of conveying the print medium in a conveying direction by a conveying member;
an ink depositing step of depositing ink on the print medium;
A printing method including a peeling step of peeling the printing medium from the transport member by a peeling member located downstream of the transport member in the transport direction, independently of the transport of the printing medium by the transport member.