Printing apparatus, printing system, and printing method

Abstract

A printing apparatus includes: a transport member capable of transporting a medium positioned on a surface in a transport direction; an ink head capable of adhering ink to the medium; a peeling member that is located on the downstream side of the conveyance member in the conveyance direction and is capable of peeling the medium (M) from the conveyance member; a conveyance drive unit capable of driving the conveyance member; and a peeling drive unit that can be controlled independently from the transport drive unit and can drive the peeling member.

Description

Technical Field

[0001] The present invention relates to a printing device, a printing system, and a printing method. Background Art

[0002] Patent Document 1 discloses an inkjet printing device applied to a textile printing system. The printing device includes: a conveyor belt as a conveying member for conveying a printing medium such as a fabric; and an inkjet head for ejecting ink onto the printing medium on the conveyor belt from above. In the printing device, the printing medium is conveyed according to the circumferential movement of the conveyor belt. In the textile printing system, the printing medium printed in the printing device is introduced into a dryer via a roller in a drying unit to dry the ink. The roller in the drying unit peels the printing medium in a state of being in close contact with the conveyor belt of the printing device from the conveyor belt and introduces it into the dryer.

[0003] Prior Art Documents

[0004] Patent Documents

[0005] Patent Document 1: Japanese Unexamined Patent Application Publication No. 2017-226081 Summary of the Invention

[0006] A printing device according to one aspect of the present invention includes: a conveying member capable of conveying a printing medium located on a surface in a conveying direction; an ink unit capable of attaching ink to the printing medium; a peeling member located on the downstream side of the conveying direction of the conveying member and capable of peeling the printing medium from the conveying member; a conveying drive unit capable of driving the conveying member; and a peeling drive unit capable of being independently controlled from the conveying drive unit and capable of driving the peeling member. According to the printing device of one mode of the present invention, it is possible to suppress the printing medium from being sent downstream in a state where tension accompanying peeling from the conveying member is applied, and it is possible to adjust the position of the peeling start point of the printing medium with respect to the conveying member.

[0007] A printing system according to another aspect of the present invention includes: the above printing device; and a drying device capable of introducing the printing medium peeled from the conveying member by the peeling member in the printing device and drying the introduced printing medium. According to the printing system of another aspect of the present invention, it is possible to suppress the printing medium from being sent downstream in a state where tension accompanying peeling from the conveying member is applied, and it is possible to adjust the position of the peeling start point of the printing medium with respect to the conveying member.

[0008] In addition, a printing method according to another aspect of the present invention includes: a conveying step of conveying a printing medium in a conveying direction by a conveying member; an ink liquid attaching step of attaching ink liquid to the printing medium; and a peeling step of peeling the printing medium from the conveying member independently of the conveyance of the printing medium by the conveying member by a peeling member located on the downstream side of the conveying member in the conveying direction. According to the printing method of another aspect of the present invention and the printing apparatus of one aspect of the present invention, it is possible to suppress the printing medium from being sent downstream while being under the tension accompanied by peeling from the conveying member, and it is possible to adjust the position of the peeling start point of the printing medium relative to the conveying member. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 FIG. 1 is a side view schematically showing the structure of a printing system of a printing apparatus to which an embodiment of the present invention is applied.

[0010] Figure 2 FIG. 2 is a side view schematically showing the structure of the printing apparatus.

[0011] Figure 3 FIG. 3 is a diagram for explaining the relationship between the conveying member and the peeling member in the printing apparatus.

[0012] Figure 4 FIG. 4 is a timing chart for explaining the operation of the printing apparatus.

[0013] Figure 5 FIG. 5 is a flowchart showing the processing flow of the printing method. DETAILED DESCRIPTION OF THE INVENTION

[0014] In the conventional dyeing and printing system as described above, when the printing medium is peeled from the conveying belt by the roller in the drying section, sometimes the printing medium is conveyed to the dryer on the downstream side in the conveying direction while being under the tension accompanied by peeling from the conveying belt. In this case, since the printing medium may be dried in a stretched state when it is a cloth, there is a possibility that deformation may occur in the image formed on the printing medium, resulting in a reduction in printing quality. In addition, when the printing medium is peeled from the conveying belt by the roller in the drying section, it is difficult to adjust the position of the peeling start point of the printing medium relative to the conveying belt. When the position of the peeling start point of the printing medium in the area above the conveying belt shifts toward the inkjet head side, there is a possibility that the portion of the printing medium to which the ink liquid of the inkjet head is to be ejected may be peeled from the conveying belt. On the other hand, when the position of the peeling start point of the printing medium relative to the conveying belt reaches the area on the lower side of the conveying belt, there is a possibility that the printing medium cannot be peeled from the conveying belt, resulting in poor peeling of the printing medium from the conveying belt.

[0015] Therefore, there is a need for a printing apparatus, a printing system, and a printing method that can suppress the downstream feeding of a printing medium in a state where a tension accompanied by peeling from a conveying member is applied, and can adjust the position of the peeling start point of the printing medium with respect to the conveying member.

[0016] Hereinafter, a printing apparatus, a printing system, and a printing method according to an embodiment of the present invention will be described with reference to the accompanying drawings. It should be noted that hereinafter, regarding the direction relationship, an XY orthogonal coordinate orthogonal to each other on a horizontal plane will be used for description. In addition, the vertical up-and-down direction orthogonal to the X direction and the Y direction is defined as the Z direction.

[0017] Figure 1 The illustrated printing system 100 includes a printing apparatus 1 and a drying apparatus 10. The printing apparatus 1 is an apparatus including an ink unit capable of attaching ink to a medium M which is a wide and long printing medium. The printing apparatus 1 prints an image by attaching ink to the medium M using the ink unit. The drying apparatus 10 is disposed on the downstream side of the printing apparatus 1. The drying apparatus 10 is an apparatus capable of drying the medium M on which an image is printed in the printing apparatus 1.

[0018] Examples of the printing apparatus 1 include a screen printing apparatus and an inkjet printing apparatus. When the printing apparatus 1 is a screen printing apparatus, the ink unit includes a screen plate having a plurality of openings and a squeegee. In this case, the ink unit moves the ink along the screen plate in accordance with the movement of the squeegee, so that the ink adheres to the medium M through the openings of the screen plate. On the other hand, when the printing apparatus 1 is an inkjet printing apparatus, the ink unit ejects ink onto the medium M to attach the ink to the medium M. Hereinafter, the case where the printing apparatus 1 is an inkjet printing apparatus will be described in detail.

[0019] The inkjet printing apparatus 1 is suitable for digital printing of printing text or patterns and other images on a cloth member, that is, a medium M, made of a cloth such as a textile or a knitted fabric. The medium M is a long cloth member extending between the printing apparatus 1 and the drying apparatus 10. The cloth member includes a variety of cloths with different stretchabilities. Of course, the printing apparatus 1 can also be used for printing various images on printing media such as paper sheets and resin sheets.

[0020] As shown in Figure 1 and Figure 2 the printing apparatus 1 includes a conveying unit 3, a printing unit 4, a peeling member 5, a peeling drive unit 50, a detection unit 6, and a control unit 7.

[0021] The conveying unit 3 is a unit for conveying the medium M in the Y direction. The conveying unit 3 includes a conveying member 31, a first conveying roller 32, a second conveying roller 33, and a conveying drive unit 34.

[0022] The conveying member 31 is a member capable of conveying the medium M located on its surface. In the present embodiment, the conveying member 31 is an annular belt having a width in the X direction and extending in the Y direction. The conveying member 31 formed of the annular belt can move in a circumferential manner. By moving circumferentially along the Y direction, the conveying member 31 can convey the medium M in a state of being in contact with the surface of the conveying member 31 in the conveying direction H1 from one side to the other side in the Y direction. On the surface of the conveying member 31, an adhesive layer formed of an adhesive for adhering the medium M is formed to hold the medium M in a state of being in contact with the surface of the conveying member 31.

[0023] The first conveying roller 32 is a cylindrical roller extending in the X direction, and is a roller around which the conveying member 31 is wound at the most downstream position in the conveying direction H1 of the medium M in the conveying member 31. The first conveying roller 32 rotates idly according to the circumferential movement of the conveying member 31. The second conveying roller 33 is a cylindrical roller extending in the X direction, and is a roller around which the conveying member 31 is wound at the most upstream position in the conveying direction H1 of the medium M in the conveying member 31. The conveying member 31 is supported by the first conveying roller 32 and the second conveying roller 33 in such a manner that the portion between the first conveying roller 32 and the second conveying roller 33 on its surface extends in the X direction and the Y direction and becomes horizontal.

[0024] The conveying drive unit 34 is a drive motor that generates a driving force for rotating the second conveying roller 33. The conveying drive unit 34 can drive the conveying member 31 by driving the second conveying roller 33 to rotate. That is, the conveying member 31 can convey the medium M in the conveying direction H1 along the Y direction by moving circumferentially according to the rotation of the second conveying roller 33 achieved by the drive of the conveying drive unit 34.

[0025] The printing unit 4 is a unit for printing an image on the medium M in a state of being in contact with the surface of the conveying member 31. The printing unit 4 is a unit in which an inkjet head 42 having an ink head 421, a pre-treatment liquid head 422, and a post-treatment liquid head 423 is mounted on a carriage 41. The printing unit 4 is disposed above the conveying member 31 in the Z direction. The printing apparatus 1 is a so-called serial printer that performs printing processing on the medium M in a serial printing manner. In the printing apparatus 1 using the serial printing method, the ejection operation of ejecting various liquids from the inkjet head 42 while repeatedly moving the carriage 41 reciprocally in the X direction orthogonal to the conveying direction H1 of the medium M, that is, the Y direction on the horizontal plane, and the conveying operation of the medium M performed by the conveying member 31 are repeated.

[0026] The carriage 41 is fixed to a timing belt 212 assembled to a flat carriage guide 21 having guide rails 211 extending in the X direction. The timing belt 212 is an endless belt assembled to the carriage guide 21 so as to be movable around in the X direction. The carriage 41 can be guided by the guide rails 211 as the timing belt 212 moves around in the X direction, and reciprocates in the X direction along the carriage guide 21.

[0027] A liquid head 421, a pretreatment liquid head 422, and a post-treatment liquid head 423 included in the inkjet head 42 mounted on the carriage 41 respectively convey a medium M in the Y direction by a conveying member 31, and the carriage 41 reciprocates in the X direction, so that relative movement in the X direction and the Y direction can be achieved with respect to the medium M. In this case, the X direction indicating the moving direction of the carriage 41 becomes the main scanning direction, and the Y direction indicating the conveying direction H1 of the medium M becomes the sub-scanning direction.

[0028] A plurality of liquid heads 421 are mounted on the carriage 41. The plurality of liquid heads 421 are each a liquid unit capable of attaching ink containing a coloring agent to the medium M on the conveying member 31 by ejecting the ink. The plurality of liquid heads 421 each include: a plurality of nozzles for ejecting ink droplets in an ejection method such as a piezoelectric method using a piezoelectric element or a thermal method using a heating element; an ink flow path for guiding the ink to the nozzle; and a wiring substrate for controlling the ejection operation of the ink. The plurality of liquid heads 421 are mounted on the carriage 41 in two rows arranged in the X direction. Two liquid heads 421 ejecting the same color ink are mounted on the carriage 41 so as to be disposed at positions offset from each other in the X direction and the Y direction. As another embodiment, a structure in which one liquid head 421 is mounted on the carriage 41 can be cited.

[0029] The pretreatment liquid head 422 is mounted on the carriage 41 so as to be disposed upstream of the liquid head 421 in the conveying direction H1 of the medium M by the conveying member 31. The pretreatment liquid head 422 is a pretreatment liquid unit capable of attaching the pretreatment liquid to the medium M on the conveying member 31 before the ink by ejecting the pretreatment liquid. The pretreatment liquid head 422 includes: a plurality of nozzles for ejecting the pretreatment liquid in an ejection method such as a piezoelectric method using a piezoelectric element or a thermal method using a heating element; a pretreatment liquid flow path for guiding the pretreatment liquid to the nozzle; a wiring substrate for controlling the ejection operation of the pretreatment liquid. The pretreatment liquid is a treatment liquid that contacts the ink in a non-dried state on the medium M and is a non-color-developing treatment liquid that does not develop color even when attached to the medium M. It should be noted that the pretreatment liquid unit for attaching the pretreatment liquid to the medium M on the conveying member 31 is not limited to the head structure such as the pretreatment liquid head 422, and may also be a spraying structure for spraying the pretreatment liquid.

[0030] The post-treatment liquid head 423 is mounted on the carriage 41 so as to be disposed on the downstream side of the ink liquid head 421 in the conveyance direction H1 of the conveyance medium M of the conveyance member 31. The post-treatment liquid head 423 is a post-treatment liquid unit that can cause the post-treatment liquid to adhere to the conveyance medium M after the ink liquid by ejecting the post-treatment liquid. The post-treatment liquid head 423 includes: a plurality of nozzles that eject the post-treatment liquid by an ejection method such as a piezoelectric method using a piezoelectric element, a thermal method using a heating element, etc.; a post-treatment liquid flow path that guides the post-treatment liquid to the nozzle; and a wiring substrate for controlling the ejection operation of the post-treatment liquid. The post-treatment liquid is a treatment liquid that contacts the ink liquid in an undried state on the medium M and is a non-color-developing treatment liquid that does not develop color even when adhered to the medium M. The post-treatment liquid has a function of improving the fixing property of the ink liquid on the medium M. As such a post-treatment liquid, a treatment liquid containing silicone oil can be used. It should be noted that the post-treatment liquid unit that causes the post-treatment liquid to adhere to the conveyance medium M of the conveyance member 31 is not limited to the head structure such as the post-treatment liquid head 423, and may also be a spraying structure that sprays the post-treatment liquid.

[0031] In the printing unit 4, for the medium M in a state of being in contact with the surface of the conveyance member 31, a liquid ejection operation of ejecting the pre-treatment liquid from the pre-treatment liquid head 422, ejecting the ink liquid from the ink liquid head 421, and ejecting the post-treatment liquid from the post-treatment liquid head 423 as needed is performed. Thereby, an image is printed on the medium M. That is, on the medium M on the conveyance member 31, after the pre-treatment liquid ejected from the pre-treatment liquid head 422 adheres, the ink liquid ejected from the ink liquid head 421 adheres, and then, as needed, the post-treatment liquid ejected from the post-treatment liquid head 423 adheres.

[0032] The pre-treatment liquid ejected from the pre-treatment liquid head 422 is a treatment liquid containing an aqueous solvent mainly composed of water and a positively charged cationic resin. The ink liquid ejected from the ink liquid head 421 is a pigment ink liquid containing a pigment as a colorant. The pigment ink liquid is an ink liquid containing an aqueous medium mainly composed of water, a pigment, and a binder resin. The pigment can be an anionic pigment. Since the anionic pigment and the cationic resin contained in the pre-treatment liquid ejected from the pre-treatment liquid head 422 undergo an electro-reaction aggregation on the medium M, it is possible to suppress the penetration of the binder resin contained in the pigment ink liquid into the medium M. Thus, in the case where the medium M is a cloth member, it is possible to reduce the case where the binder resin penetrates into the gaps between the fibers and causes the fibers to adhere to each other. Therefore, it is possible to improve the feeling such as the skin touch of the cloth member.

[0033] The peeling member 5 is a member located on the downstream side of the conveying member 31 in the conveying direction H1. Specifically, the peeling member 5 is provided at a position separated upward and downstream in the conveying direction H1 from the downstream end portion 311 of the conveying member 31 located at the downstream end in the conveying direction H1. The downstream end portion 311 is the portion of the conveying member 31 wound around the first conveying roller 32. When observed from each of the Y direction and the Z direction, the peeling member 5 is provided in such a manner that a part of the peeling member 5 overlaps with the downstream end portion 311. In addition, the peeling member 5 is located above the extension line of the conveying direction H1 of the medium M on the conveying member 31. The peeling member 5 can peel the medium M in a state of being in contact with the surface of the conveying member 31 from the conveying member 31. In the present embodiment, the peeling member 5 is a cylindrical roller extending in the X direction. The peeling member 5 constituted by the roller is provided so as to be rotatable about an axis extending in the X direction.

[0034] On the outer peripheral surface 5A of the peeling member 5, a specified area MM in the conveying direction H1 of the medium M extending between the printing device 1 and the drying device 10 is wound from the upper side in the Z direction. The medium M in contact with the surface of the conveying member 31 and having the specified area MM wound around the peeling member 5 peels upward from the conveying member 31 with the peeling starting point MPP as a boundary with respect to the contact portion M1 in contact with the surface of the conveying member 31. By rotating in a state where the specified area MM of the medium M is attached to the outer peripheral surface 5A from the upper side, the peeling member 5 can peel the portion of the medium M in contact with the surface of the conveying member 31 and located upstream of the specified area MM in the conveying direction H1 from the conveying member 31. The rotation direction of the peeling member 5 when peeling the medium M from the conveying member 31 is the same as the rotation direction of the first conveying roller 32 when conveying the medium M in the conveying direction H1 by the circumferential movement of the conveying member 31.

[0035] In a state where the medium M is wound around the outer peripheral surface 5A of the peeling member 5, a frictional force is generated between the wound portion M21 of the medium M with respect to the outer peripheral surface 5A and the outer peripheral surface 5A. By rotating the peeling member 5, the medium M is peeled from the conveying member 31 based on the frictional force between the wound portion M21 and the outer peripheral surface 5A, and the medium M is sent out toward the downstream drying device 10. In this case, in the peeled portion M2 of the medium M peeled from the conveying member 31 by the peeling member 5, a tension accompanied by the peeling from the conveying member 31 is applied to the region 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 region on the downstream side compared to the peeling member 5. Therefore, it is possible to suppress the case where the medium M is sent out downstream in a state where tension is applied as it is peeled from the conveying member 31. As a result, since it is possible to suppress the case where the medium M introduced into the drying device 10 disposed on the downstream side of the peeling member 5 is dried in a stretched state, it is possible to suppress the case where the image formed on the medium M is deformed or the like, resulting in a decrease in printing quality.

[0036] In addition, the medium M peeled from the conveying member 31 by the peeling member 5 is set in a bent state bent downward in the Z direction between the peeling member 5 and the drying device 10 and is introduced into the drying device 10. Thereby, it is possible to more reliably suppress the case where the medium M introduced into the drying device 10 is dried in a stretched state.

[0037] As Figure 2 shown, the peeling member 5 has a base body 51 and a surface layer 52 provided on the base body 51 and forming the outer peripheral surface 5A. The surface layer 52 is made of a rubber material. By making the surface layer 52 forming the outer peripheral surface 5A of the peeling member 5 a rubber material, it is possible to increase the frictional force between the wound portion M21 of the medium M with respect to the outer peripheral surface 5A and the outer peripheral surface 5A. Thereby, the peeling member 5 can more reliably peel the medium M from the conveying member 31 based on the frictional force.

[0038] The rubber material forming the surface layer 52 of the peeling member 5 may also be a foaming rubber material. The surface layer 52 made of a foaming rubber material has a plurality of pores. In this case, in a state where the medium M is wound around the outer peripheral surface 5A of the peeling member 5, even if the ink on the medium M is transferred to the outer peripheral surface 5A, the transferred ink can be captured in the pores of the surface layer 52. Thereby, it is possible to suppress the case where the outer peripheral surface 5A easily slides as the ink is transferred with respect to the outer peripheral surface 5A of the peeling member 5.

[0039] In addition, the surface layer 52 of the peeling member 5 may also be a member having a polished surface. Thus, since abrasive grains and the like are likely to get stuck on the medium M and are not easily slid, the medium M can be peeled off more reliably. As the polished surface, sandpaper with a grit size of #40 to #240 can be used, and more preferably #100 to #150. As the member having a polished surface, for example, abrasive paper with paste can be cited, and as the abrasive grains, silicon carbide abrasive grains can be cited.

[0040] When the position of the peeling start point MPP of the medium M with respect to the conveying member 31 on the medium M in a state of being in contact with the surface of the conveying member 31 is shifted toward the printing unit 4 in the region above the conveying member 31, there is a possibility that the portion of the printing object to be printed by the printing unit 4 on the medium M is peeled off from the conveying member 31. On the other hand, when the position of the peeling start point MPP of the medium M with respect to the conveying member 31 reaches the lower region side of the conveying member 31, the medium M cannot be peeled off from the conveying member 31, and thus there may be a peeling defect of the medium M with respect to the conveying member 31. Therefore, it is necessary to adjust the position of the peeling start point MPP of the medium M with respect to the conveying member 31.

[0041] As Figure 3 shown, the position of the peeling start point MPP of the medium M with respect to the conveying member 31 changes according to the circumferential movement of the conveying member 31 and also changes according to the rotation of the peeling member 5. As described above, when the peeling member 5 is arranged such that a part of the peeling member 5 overlaps with the downstream end portion 311 of the conveying member 31 when observed in the Y direction and the Z direction respectively, the position of the peeling start point MPP of the medium M changes within the range of the downstream end portion 311 of the conveying member 31 wound around the first conveying roller 32. The position of the peeling start point MPP of the medium M changes toward the downstream side in the rotation direction of the first conveying roller 32 corresponding to the circumferential movement of the conveying member 31 within the range of the downstream end portion 311, and changes toward the upstream side in the rotation direction of the first conveying roller 32 corresponding to the rotation of the peeling member 5.

[0042] In view of the above situation, by controlling the circumferential movement of the conveying member 31 and the rotation of the peeling member 5, the position of the peeling start point MPP of the medium M with respect to the conveying member 31 can be adjusted. At this time, when the peeling member 5 is rotated synchronously with the circumferential movement of the conveying member 31, it is difficult to accurately adjust the position of the peeling start point MPP of the medium M.

[0043] Therefore, in the printing apparatus 1 of the present embodiment, a peeling drive unit 50 is provided that can be controlled independently of the conveyance drive unit 34 that causes the conveyance member 31 to move around, and can drive the peeling member 5. The peeling drive unit 50 is a drive motor that can generate a driving force for rotating the peeling member 5. The peeling drive unit 50 can rotate the peeling member 5 independently of the circumferential movement of the conveyance member 31 caused by the drive of the conveyance drive unit 34. Thereby, the position of the medium M relative to the peeling start point MPP of the conveyance member 31 can be accurately adjusted.

[0044] When the position of the medium M relative to the peeling start point MPP of the conveyance member 31 changes, the peeling angle α in the medium M changes, and the winding angle β of the winding portion M21 wound around the peeling member 5 in the medium M also changes. The peeling angle α represents the angle formed by the peeled portion M2 of the medium M that is peeled from the conveyance member 31 and is located in the region between the conveyance member 31 and the peeling member 5, and the contact portion M1 of the medium M that contacts the surface of the conveyance member 31. The winding angle β is represented by the central angle of the arc of the winding portion M21 along the outer peripheral surface 5A of the peeling member 5. When the position of the peeling start point MPP of the medium M changes downstream in the rotation direction of the first conveyance roller 32 corresponding to the circumferential movement of the conveyance member 31, the peeling angle α becomes smaller and the winding angle β becomes larger. On the other hand, when the position of the peeling start point MPP of the medium M changes upstream in the rotation direction of the first conveyance roller 32 corresponding to the rotation of the peeling member 5, the peeling angle α becomes larger and the winding angle β becomes smaller.

[0045] In the printing apparatus 1 of the present embodiment, a detection unit 6 is disposed below the peeling member 5. The detection unit 6 is a sensor that can detect the peeled portion M2 of the medium M that is peeled from the conveyance member 31 and is located in the region between the conveyance member 31 and the peeling member 5. The peeled portion M2 of the medium M that is the detection object of the detection unit 6 is a portion of the medium M that is located in the region between the portion of the conveyance member 31 corresponding to the downstream end in the conveyance 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 after being peeled from the conveyance member 31. In the present embodiment, the peeled portion M2 of the medium M that is the detection object of the detection unit 6 is a portion of the medium M that is located in the region between the downstream end portion 311 wound around the first conveyance roller 32 in the conveyance member 31 and the outer peripheral surface 5A of the peeling member 5 after being peeled from the conveyance member 31. The detection unit 6 is, for example, a photoelectric sensor that can adjust the detection range 61. The detection unit 6 constituted by the photoelectric sensor can detect the peeled portion M2 by emitting detection light from the light emitting unit and receiving the light reflected by the peeled portion M2 of the medium M using the light receiving unit. The detection unit 6 can adjust the detection range 61 on the optical path through which the detection light passes.

[0046] The detection unit 6 sets a specified range on the optical path perpendicular to the plane VP extending in the X direction that includes the center 32S of the first transfer roller 32 and the center 5S of the peeling member 5 as the detection range 61 within the region between the downstream end portion 311 of the transfer member 31 and the outer peripheral surface 5A of the peeling member 5. The detection unit 6 becomes in an on state when the peeling portion M2 of the medium M is within the detection range 61, and becomes in an off state when the peeling portion M2 of the medium M is outside the detection range 61. The detection result of the detection unit 6 is referred to by the control unit 7 described later.

[0047] The control unit 7 is a personal computer having a CPU (Central Processing Unit), an HDD (Hard Disk Drive) storing processing programs, a storage area such as a flash memory, and a RAM (Random Access Memory) used as the working area of the CPU. The control unit 7 executes the processing of each step of the printing method using the printing apparatus 1 by the CPU executing the processing programs stored in the HDD and the flash memory. Refer to Figure 3 、 Figure 4 and Figure 5 The processing of each step of the printing method executed by the control unit 7 will be described.

[0048] The control unit 7 performs the processing of each step of the printing process including a pre-treatment liquid attachment step S1, an ink liquid attachment step S2, and a post-treatment liquid attachment step S3, a transfer step S4, and a peeling step S5.

[0049] In the pre-treatment liquid attachment step S1, the control unit 7 performs a pre-treatment liquid attachment process in which the pre-treatment liquid is attached to the medium M in a state of being in contact with the surface of the transfer member 31 by ejecting the pre-treatment liquid from the pre-treatment liquid head 422. In the ink liquid attachment step S2, the control unit 7 performs an ink liquid attachment process in which the ink liquid is attached to the medium M in a state of being in contact with the surface of the transfer member 31 by ejecting the ink liquid from the ink liquid head 421. In the post-treatment liquid attachment step S3, the control unit 7 performs a post-treatment liquid attachment process in which the post-treatment liquid is attached to the medium M in a state of being in contact with the surface of the transfer member 31 by ejecting the post-treatment liquid from the post-treatment liquid head 423. It should be noted that it is not limited to the control unit 7 performing the pre-treatment liquid attachment process, the ink liquid attachment process, and the post-treatment liquid attachment process. For example, it may be that the pre-treatment liquid head 422 performs the pre-treatment liquid attachment process, the ink liquid head 421 performs the ink liquid attachment process, and the post-treatment liquid head 423 performs the post-treatment liquid attachment process.

[0050] In the conveying process S4, the control unit 7 performs a conveying drive process of driving the conveying drive unit 34 corresponding to each of the pretreatment liquid adhesion process, the ink liquid adhesion process, and the post-treatment liquid adhesion process. The control unit 7 causes the conveying member 31 to perform a circumferential movement by driving the conveying drive unit 34 in the conveying drive process, thereby conveying the medium M in a state of being in contact with the surface of the conveying member 31 in the conveying direction H1. It should be noted that it is not limited to the control unit 7 performing the conveying drive process. For example, the conveying drive unit 34 may perform the conveying drive process.

[0051] In the peeling process S5, the control unit 7 performs a peeling drive process of driving the peeling drive unit 50. The control unit 7 rotates the peeling member 5 according to the drive of the peeling drive unit 50 in the peeling drive process, thereby peeling the medium M in a state of being in contact with the surface of the conveying member 31 from the conveying member 31. Specifically, the control unit 7 rotates the peeling member 5 independently according to the drive of the peeling drive unit 50 with respect to the circumferential movement of the conveying member 31 caused by the drive of the conveying drive unit 34. Thereby, compared with the case where the peeling member 5 is rotated synchronously with the circumferential movement of the conveying member 31, the position of the peeling start point MPP of the medium M with respect to the conveying member 31 can be accurately adjusted.

[0052] Refer to Figure 3 and Figure 4 , and the pretreatment liquid adhesion process of the pretreatment liquid adhesion process S1, the ink liquid adhesion process of the ink liquid adhesion process S2, the post-treatment liquid adhesion process of the post-treatment liquid adhesion process S3, the conveying drive process of the conveying process S4, and the peeling drive process of the peeling process S5 performed by the control unit 7 will be described in more detail. It should be noted that in the following description, the ink head 421, the pretreatment liquid head 422, and the post-treatment liquid head 423 are collectively referred to as "ink jet head 42", the ink liquid, the pretreatment liquid, and the post-treatment liquid are collectively referred to as "liquid", and the ink liquid adhesion process, the pretreatment liquid adhesion process, and the post-treatment liquid adhesion process are collectively referred to as "liquid adhesion process".

[0053] The control unit 7 repeatedly performs a liquid attachment process of ejecting a liquid from the inkjet head 42 while moving the carriage 41 carrying the inkjet head 42 in the X direction at a prescribed head scan cycle HSC, and a conveyance drive process of driving the conveyance drive unit 34 corresponding to the liquid attachment process. When the control unit 7 is in the "on" state where the liquid is ejected from the inkjet head 42 during the liquid attachment process, it is in the "off" state where the drive of the conveyance drive unit 34 is stopped during the conveyance drive process. When the control unit 7 is in the "off" state where the ejection of the liquid from the inkjet head 42 is stopped during the liquid attachment process, it is in the "on" state where the conveyance drive unit 34 is driven during the conveyance drive process. That is, the control unit 7 switches the drive and the drive stop of the conveyance drive unit 34 in the conveyance drive process according to the switching between the ejection and the stop of the liquid from the inkjet head 42 during the liquid attachment process. By repeatedly performing the liquid attachment process and the conveyance drive process implemented by the control unit 7, an image is printed on the medium M in a state of being in contact with the surface of the conveyance member 31.

[0054] In the conveyance drive process, the control unit 7 drives the conveyance drive unit 34 so that the speed of the circumferential movement of the conveyance member 31 corresponding to the drive of the conveyance drive unit 34 becomes a prescribed conveyance movement speed VB, and the movement distance of the circumferential movement of the conveyance member 31 corresponding to the drive of the conveyance drive unit 34 becomes a prescribed conveyance movement distance DB. As a result, in each conveyance drive process implemented by the control unit 7, the medium M in a state of being in contact with the surface of the conveyance member 31 is conveyed in the conveyance direction H1 by a conveyance length corresponding to the conveyance movement distance DB of the conveyance member 31 at a conveyance speed equivalent to the conveyance movement speed VB of the conveyance member 31.

[0055] In a state where a prescribed region MM of the medium M is wound around the outer peripheral surface 5A of the peeling member 5 from the upper side on the downstream side in the conveyance direction H1 with respect to the conveyance member 31, the position of the peeling start point MPP of the medium M with respect to the conveyance member 31 changes toward the downstream side in the rotation direction of the first conveyance roller 32 corresponding to the circumferential movement of the conveyance member 31 within the range of the downstream end portion 311 of the conveyance member 31 wound around the first conveyance roller 32. The position of the peeling start point MPP of the medium M changes toward the downstream side in the rotation direction of the first conveyance roller 32, the peeling angle α in the medium M changes in a decreasing manner, and the winding angle β of the winding portion M21 of the medium M wound around the peeling member 5 changes in an increasing manner.

[0056] When the peeling angle α formed by the contact portion M1 and the peeling portion M2 in the medium M is less than 90 degrees and the peeling portion M2 is within the detection range 61, the detection unit 6 becomes in an on state. In this case, the position of the peeling start point MPP of the medium M changes downstream in the rotation direction of the first conveying roller 32 corresponding to the circumferential movement of the conveying member 31. When the peeling angle α becomes smaller than 90 degrees, the detection unit 6 becomes in an on state. That is, the first sensor switching timing TS1 indicating the timing when the detection unit 6 switches from an off state to an on state coincides with the timing when the peeling angle α in the medium M is less than 90 degrees. In a state where the peeling angle α of the medium M is less than 90 degrees, the winding angle β of the winding portion M21 of the medium M with respect to the peeling member 5 increases to such an extent that the frictional force between the outer peripheral surface 5A of the peeling member 5 and the winding portion M21 is sufficient to peel the medium M from the conveying member 31.

[0057] For each conveying drive process, the control unit 7 performs a peeling drive process for driving the peeling drive unit 50 based on the detection of the detection unit 6. In the peeling drive process, when the detection unit 6 is in an on state, the control unit 7 is set to an "on" state for driving 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 prescribed circumferential speed VR corresponding to the drive of the drive unit 50, and the moving distance of the outer peripheral surface 5A of the peeling member 5 along the rotation direction corresponding to the drive of the peeling drive unit 50 becomes a prescribed rotational movement distance DR. Thereby, the medium M in a state of being in contact with the surface of the conveying member 31 is peeled by a peeling length corresponding to the rotational movement distance DR of the peeling member 5 at a peeling speed equivalent to the circumferential speed VR of the peeling member 5.

[0058] The position of the peeling start point MPP of the medium M with respect to the conveying member 31 changes upstream in the rotation direction of the first conveying roller 32 corresponding to the rotation of the peeling member 5 within the range of the downstream end portion 311 of the first conveying roller 32 around which the medium M is wound. When the position of the peeling start point MPP of the medium M changes upstream in the rotation direction of the first conveying roller 32, the peeling angle α in the medium M changes in an increasing manner, and the winding angle β of the winding portion M21 of the medium M wound around the peeling member 5 changes in a decreasing manner.

[0059] According to the rotation of the peeling member 5, the position of the peeling start point MPP of the medium M changes to the upstream side in the rotation direction of the first conveying roller 32. When the peeling angle α increases to 90 degrees or more, the peeled portion M2 of the medium M is located outside the detection range 61, and the detection unit 6 becomes a disconnected state. That is, the second sensor switching timing TS2 indicating the timing when the detection unit 6 switches from the connected state to the disconnected state coincides with the timing when the peeling angle α in the medium M changes from less than 90 degrees to 90 degrees or more. In the peeling drive process, when the detection unit 6 is in the disconnected state, the control unit 7 is set to the "disconnected" state in which the drive of the peeling drive unit 50 is stopped.

[0060] As described above, the control unit 7 drives the peeling drive unit 50 based on the detection of the detection unit 6, thereby rotating the peeling member 5 independently of the circumferential movement of the conveying member 31 caused by the drive of the conveying drive unit 34. Thus, when the medium M is peeled from the conveying member 31 according to the rotation of the peeling member 5, it is possible to suppress the case where the medium M is sent downstream in a state where tension is applied as it is peeled from the conveying member 31, and it is possible to accurately adjust the position of the peeling start point MPP of the medium M with respect to the conveying member 31. Therefore, the case where the medium M introduced into the drying device 10 disposed downstream of the peeling member 5 is dried in an extended state is suppressed, the case where the portion of the medium M to which the liquid of the inkjet head 42 adheres is peeled from the conveying member 31 is suppressed, and further, the occurrence of peeling failure of the medium M with respect to the conveying member 31 is suppressed.

[0061] In addition, in the peeling drive process, the control unit 7 switches the drive of the peeling drive unit 50 from the stopped state to the drive state after a predetermined first delay time DT1 has elapsed since the first sensor switching timing TS1 at which the detection unit 6 switches from the off state to the on state. That is, the control unit 7 switches the drive of the peeling drive unit 50 from the stopped state to the drive 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 the drive state to the stopped state after a predetermined second delay time DT2 has elapsed since the second sensor switching timing TS2 at which the detection unit 6 switches from the on state to the off state. That is, the control unit 7 switches the drive of the peeling drive unit 50 from the drive state to the 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 timings after the first and second delay times DT1 and DT2 have elapsed from the respective sensor switching timings of the first and second sensor switching timings TS1 and TS2 as the respective drive switching timings of the first and second drive switching timings TM1 and TM2, it is possible to suppress the occurrence of an oscillation phenomenon in which the on state and the off state of the detection unit 6 repeat at high speed. As a result, it is possible to suppress the occurrence of a phenomenon in which the peeling drive unit 50 abnormally repeats the drive state and the stopped state along with the oscillation of the detection unit 6.

[0062] In addition, during 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 is within a specified allowable range based on the conveyance movement distance DB of the conveyance member 31. For example, the lower limit value of the allowable range is set to the same value as the conveyance movement distance DB, and the upper limit value of the allowable range is set to twice the value of the conveyance movement distance DB. That is, the control unit 7 drives the peeling drive unit 50 in response to the detection unit 6 being in an on state so that the rotational movement distance DR of the peeling member 5 is equal to or greater than the conveyance movement distance DB and equal to or less than twice the conveyance movement distance DB (DB ≤ DR ≤ 2DB). 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 conveyance movement distance DB, it is possible to suppress the situation where the position of the peeling start point MPP of the medium M relative to the conveyance member 31 is too far downstream in the rotational direction of the first conveyance roller 32 when the medium M is peeled from the conveyance member 31 due to the rotation of the peeling member 5 caused by the drive of the peeling drive unit 50. As a result, it is possible to suppress the situation where the printed surfaces of the contact portion M1 and the peeled portion M2 of the medium M come into contact with each other between the downstream end portion 311 of the conveyance 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 equal to or less than twice the conveyance movement distance DB, it is possible to suppress the situation where the position of the peeling start point MPP of the medium M relative to the conveyance member 31 is too far upstream in the rotational direction of the first conveyance roller 32 when the medium M is peeled from the conveyance member 31 due to the rotation of the peeling member 5 caused by the drive of the peeling drive unit 50. As a result, it is possible to suppress the peeling of the portion of the medium M where the liquid from the inkjet head 42 is to be attached from the conveyance member 31.

[0063] In addition, during the peeling drive process, the control unit 7 drives the peeling drive unit 50 so that the circumferential speed VR of the rotation of the peeling member 5 corresponding to the drive of the peeling drive unit 50 is equal to or less than the conveyance movement speed VB of the circumferential movement of the conveyance member 31 corresponding to the drive of the conveyance drive unit 34 (VR ≤ VB). As a result, it is possible to suppress the situation where the position of the peeling start point MPP of the medium M relative to the conveyance member 31 is too far upstream in the rotational direction of the first conveyance roller 32 when the medium M is peeled from the conveyance member 31 due to the rotation of the peeling member 5 caused by the drive of the peeling drive unit 50. Therefore, it is possible to more reliably suppress the peeling of the portion of the medium M where the liquid from the inkjet head 42 is to be attached from the conveyance member 31.

[0064] In addition, during the peeling drive process, after the control unit 7 starts driving the peeling drive unit 50 corresponding to the first sensor switching timing TS1 when the detection unit 6 switches from the off state to the on state, if the on state of the detection unit 6 continues even after a time equivalent to the head scan cycle HSC, an error message is output. When the peeling member 5 rotates according to the drive of the peeling drive unit 50 but the on state of the detection unit 6 continues, the medium M cannot be peeled from the conveyance member 31, which may cause poor peeling of the medium M from the conveyance member 31. Therefore, the control unit 7 outputs an error message. Based on the output of the error message, the control unit 7 can display the error message on a display unit such as a display, or can stop the printing apparatus 1. Thus, the operator of the printing apparatus 1 can take measures to improve the poor peeling of the medium M from the conveyance member 31.

[0065] Explanation of Reference Numerals

[0066] 1 Printing apparatus

[0067] 3 Conveyance unit

[0068] 31 Conveyance member

[0069] 34 Conveyance drive unit

[0070] 4 Printing unit

[0071] 42 Inkjet head

[0072] 421 Ink liquid head (ink liquid unit)

[0073] 5 Peeling member

[0074] 50 Peeling drive unit

[0075] 51 Substrate

[0076] 52 Surface layer

[0077] 6 Detection unit

[0078] 61 Detection range

[0079] 7 Control unit

[0080] 10 Drying device

[0081] 100 Printing system

[0082] M Medium (printing medium).

Claims

1. A printing device, wherein, the printing device includes: a conveying member capable of conveying a printing medium located on a surface in a conveying direction; an ink unit capable of attaching ink to the printing medium; a peeling member located on the downstream side of the conveying member in the conveying direction and capable of peeling the printing medium from the conveying member; a conveying drive unit capable of driving the conveying member; and a peeling drive unit capable of being controlled independently of the conveying drive unit and capable of driving the peeling member.

2. The printing device according to claim 1, wherein, the peeling member is arranged to be rotatable in a state of a specified area in the conveying direction where the printing medium is attached, and is capable of peeling a portion of the printing medium upstream of the specified area in the conveying direction from the conveying member according to the rotation.

3. The printing device according to claim 2, wherein, the printing device further includes: a detection unit capable of detecting a peeled portion of the printing medium in an area between the conveying member and the peeling member after being peeled from the conveying member; and a control unit that performs an ink attachment process of attaching ink to the printing medium by the ink unit, a conveying drive process of driving the conveying drive unit according to the ink attachment process, and a peeling drive process of driving the peeling drive unit according to the detection by the detection unit.

4. The printing device according to claim 3, wherein, the detection unit becomes an on state when the peeled portion is within a detection range set in an area between the conveying member and the peeling member, and becomes an off state when the peeled portion is outside the detection range; in the peeling drive process, the control unit drives the peeling drive unit when in the on state and stops the drive of the peeling drive unit when in the off state.

5. The printing device according to claim 4, wherein, the detection unit becomes the on state when the peeled portion is within the detection range in a state where an angle formed by a contact portion in contact with the surface of the conveying member and the peeled portion of the printing medium is less than 90 degrees.

6. The printing device according to claim 4 or 5, wherein, in the peeling drive process, the control unit switches between driving and stopping the peeling drive unit after a specified delay time has elapsed from the timing of switching between the on state and the off state of the detection unit.

7. The printing device according to any one of claims 4 to 6, wherein, in the peeling drive process, the control unit drives the peeling drive unit so that a rotational movement distance of an outer peripheral surface of the peeling member corresponding to the drive of the peeling drive unit converges within a specified allowable range based on a conveying movement distance of the conveying member corresponding to the drive of the conveying drive unit in the conveying drive process.

8. The printing apparatus according to any one of claims 4 to 7, wherein in the peeling driving process, the control unit drives the peeling driving unit so that the circumferential speed of rotation of the peeling member corresponding to the driving of the peeling driving unit becomes equal to or lower than the conveying moving speed of the conveying member corresponding to the driving of the conveying driving unit in the conveying driving process.

9. The printing apparatus according to any one of claims 2 to 8, wherein the peeling member has a base body and a surface layer made of a rubber material provided on the base body.

10. The printing apparatus according to claim 9, wherein the surface layer has a plurality of voids.

11. The printing apparatus according to any one of claims 1 to 10, wherein the printing medium is a cloth member made of cloth.

12. A printing system, wherein the printing system includes: the printing apparatus according to any one of claims 1 to 11; and a drying apparatus that can dry the printing medium peeled from the conveying member by the peeling member in the printing apparatus.

13. A printing method, wherein the printing method includes: a conveying step of conveying a printing medium in a conveying direction by a conveying member; an ink adhering step of adhering ink to the printing medium; and a peeling step of peeling the printing medium from the conveying member independently of the conveying of the printing medium by the conveying member by a peeling member located on the downstream side of the conveying direction of the conveying member.

Images