Inkjet recording apparatus and wiping method

Abstract

To provide an inkjet recording apparatus capable of preventing mixing between a processing liquid and an ink.SOLUTION: An inkjet recording apparatus includes a processing liquid head ejecting a processing liquid, an ink head ejecting an ink, a processing liquid wiper wiping the processing liquid head, an ink wiper wiping the ink head, and an ink container including a first opening receiving the ink. A movement range of the processing liquid wiper during the wiping is set to a position avoiding a region directly above the first opening.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present disclosure relates to an inkjet recording apparatus including a treatment liquid head that ejects a treatment liquid and an ink head that ejects ink. [Background technology]

[0002] An inkjet recording device such as an inkjet printer includes an ink head that ejects ink for forming an image toward a recording medium, and a treatment liquid head that ejects a predetermined treatment liquid. For example, when the recording medium is a fiber sheet such as a woven or knitted fabric, or a plastic sheet, it may be necessary to apply a pretreatment liquid or a posttreatment liquid to the recording medium before and after ejecting the ink toward the recording medium. The pretreatment liquid is, for example, a treatment liquid for improving the fixation of the ink to the recording medium and the coagulation of the ink pigment. The posttreatment liquid is, for example, a treatment liquid for improving the robustness of a printed image. In this case, the inkjet recording device is provided with a treatment liquid head that ejects the pretreatment liquid and the posttreatment liquid in addition to the ink head.

[0003] In general, an inkjet recording device includes a printing area where printing processing is performed, as well as a maintenance area for the ink heads and processing liquid heads (for example, Patent Document 1). In the maintenance area, processing is performed to unclog the nozzles that eject the ink or processing liquid, and to remove dirt from the nozzle arrangement surface of the head. For this processing, a purging operation in which pressurized liquid is ejected from the nozzles, and a wiping operation in which the nozzle arrangement surface is wiped with a wiper equipped with a wiping member such as a blade are performed. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2005-262561 A Summary of the Invention [Problem to be solved by the invention]

[0005] An object of the present disclosure is to provide an inkjet recording apparatus in which mixing of the treatment liquid and the ink is unlikely to occur. [Means for solving the problem]

[0006] An inkjet recording device according to one aspect of the present disclosure includes a treatment liquid head that ejects a treatment liquid, an ink head that ejects ink, a treatment liquid wiper that wipes the treatment liquid head, an ink wiper that wipes the ink head, and an ink container having a first opening that receives the ink. A movement range of the treatment liquid wiper during wiping is set to a position that avoids being directly above the first opening. Note that the "position that avoids being directly above" includes a position outside the space above the first opening, as well as a position where another member is interposed between a partial area of ​​the first opening and the treatment liquid wiper. [Brief description of the drawings]

[0007] [Figure 1] FIG. 1 is a perspective view showing the overall configuration of an inkjet printer according to an embodiment of the present disclosure. [Diagram 2] FIG. 2 is a schematic cross-sectional view taken along line II-II in FIG. [Diagram 3] FIG. 3 is an enlarged perspective view of the carriage and the maintenance unit shown in FIG. [Figure 4] FIG. 4 is a schematic cross-sectional view of the carriage and the maintenance unit. [Diagram 5] FIG. 5 is a block diagram showing the control configuration of the inkjet printer. [Figure 6] FIG. 6 is an overall perspective view of the maintenance unit. [Figure 7] FIG. 7 is a perspective view of the maintenance unit shown in FIG. 6 with the cleaning unit removed. [Figure 8A] FIG. 8A is a perspective view of the state in FIG. 7 from which the wiping unit has been further removed. [Figure 8B]FIG. 8B is an enlarged view of the processing liquid container and its vicinity in FIG. 8A. [Figure 9] The upper diagram in FIG. 9 is a plan view of the wiping unit, and the lower diagram in FIG. 9 is a plan view showing the arrangement of the ink heads mounted on the carriage. [Figure 10] FIG. 10 is a perspective view of one of the wipers included in the wiping unit. [Figure 11A] FIG. 11A is a perspective view of the maintenance unit viewed from a different perspective direction than in FIG. [Figure 11B] FIG. 11B is an enlarged view of the drive system of the wiping unit. [Figure 12] FIG. 12 is a perspective view for explaining the movement direction of the wiping unit. [Figure 13] FIG. 13 is a top view of the maintenance unit showing the movement path of the wiping unit. [Figure 14A] FIG. 14A is a schematic diagram showing an example of the arrangement of a treatment liquid container that avoids being located directly above the opening of an ink container, and is a cross-sectional view in the left-right direction of the treatment liquid container. [Figure 14B] FIG. 14B is a cross-sectional view in the left-right direction showing an example of the arrangement of the treatment liquid containers. [Figure 14C] FIG. 14C is a left-right cross-sectional view showing an example of the arrangement of the treatment liquid containers. [Figure 14D] FIG. 14D is a top view showing an example of the arrangement of the processing liquid containers. [Figure 15A] FIG. 15A is a schematic diagram for explaining the movement range of the treatment liquid wiper during wiping. [Figure 15B] FIG. 15B is a schematic diagram for explaining the movement range of the treatment liquid wiper during wiping. [Figure 15C] FIG. 15C is a schematic diagram for explaining the movement range of the treatment liquid wiper during wiping. [Figure 16A] FIG. 16A is a schematic side view showing the ink wiper and its cleaning member. [Figure 16B] FIG. 16B is a perspective view of a main part of the maintenance unit, showing the arrangement of the cleaning members. [Figure 17] FIG. 17 is a plan view showing the inclination arrangement of the ink blade and the treatment liquid blade. [Figure 18A] FIG. 18A is a diagram showing a state in which a head is wiped by a blade with no inclination. [Figure 18B] FIG. 18B is a diagram showing a state in which the head is wiped by the inclined treatment liquid blade and ink blade. [Figure 18C] FIG. 18C is a diagram showing a state in which the head is wiped by the inclined treatment liquid blade and ink blade. [Figure 19] FIG. 19 is a plan view showing another example of the inclination arrangement of the wipers. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] Hereinafter, an embodiment of the present disclosure will be described with reference to the drawings. In this embodiment, as a specific example of an inkjet recording device, an inkjet printer equipped with an ink head that ejects ink for forming an image on a wide and long recording medium is exemplified. The inkjet printer of this embodiment is suitable for digital textile printing that prints images such as characters and patterns by an inkjet method on a recording medium made of fabric such as woven fabric or knitted fabric. Of course, the inkjet recording device according to the present disclosure can also be used for printing various inkjet images on recording media such as paper sheets and resin sheets.

[0009] [Overall configuration of inkjet printer] Fig. 1 is a perspective view showing the overall configuration of an inkjet printer 1 according to an embodiment of the present disclosure, and Fig. 2 is a schematic cross-sectional view taken along line II-II in Fig. 1. The inkjet printer 1 is a printer that prints images on a wide and long workpiece W by an inkjet method, and includes a device frame 10, and a workpiece transport section 20 and a carriage 3 that are incorporated into this device frame 10. Note that in this embodiment, the left-right direction is the main scanning direction when printing on the workpiece W, and the direction from the rear to the front is the sub-scanning direction, which is the transport direction F of the workpiece W.

[0010] The device frame 10 forms a framework for mounting various components of the inkjet printer 1. The work transport unit 20 is a mechanism that intermittently feeds the work W so that the work W progresses in a transport direction F from rear to front through a printing area where inkjet printing processing is performed. The carriage 3 is equipped with an ink head 4, a pre-processing head 5, a post-processing head 6, and a sub-tank (not shown), and moves back and forth in the left and right directions during the inkjet printing processing.

[0011] The device frame 10 includes a central frame 111, a right frame 112, and a left frame 113. The central frame 111 forms a framework for mounting various components of the inkjet printer 1, and has a left-right width corresponding to the work transport section 20. The right frame 112 is erected to the right of the central frame 111, and the left frame 113 is erected to the left of the central frame 111. Between the right frame 112 and the left frame 113 is the printing area 12 where printing processing is performed on the work W.

[0012] The right frame 112 forms a maintenance area 13. The maintenance area 13 is an area where the carriage 3 is retracted when the printing process is not being performed. The maintenance unit 7 is disposed in the maintenance area 13. The maintenance unit 7 is located below the retracted carriage 3. The maintenance unit 7 is a unit for performing a wiping process for wiping the lower surfaces (nozzle arrangement surfaces) of the ink heads 4, pre-processing head 5, and post-processing head 6, and for purging the nozzles. The maintenance unit 7 also functions as a cap for preventing the heads 4, 5, and 6 from drying out when they are at rest. The left frame 113 forms a turn-around area 14 for the carriage 3. The turn-around area 14 is an area where the carriage 3 temporarily enters after scanning the printing area 12 from right to left in the printing process before scanning in the opposite direction.

[0013] A carriage guide 15 for reciprocating the carriage 3 in the left-right direction is attached to the upper side of the device frame 10. The carriage guide 15 is a flat plate-shaped member that is long in the left-right direction, and is disposed above the work transport section 20. A timing belt 16 is attached to the carriage guide 15 so as to be capable of circulating in the left-right direction (main scanning direction). The timing belt 16 is an endless belt, and is driven by a drive source (not shown) to circulate leftward or rightward.

[0014] A pair of upper and lower guide rails 17 are provided on the carriage guide 15 so as to extend parallel to the left-right direction. The carriage 3 has an engagement portion for engaging with the guide rails 17. The carriage 3 is fixed to a timing belt 16. The carriage 3 moves leftward or rightward along the carriage guide 15 while being guided by the guide rails 17 as the timing belt 16 moves leftward or rightward.

[0015] Referring mainly to FIG. 2, the work transport section 20 includes a feed roller 21 that pays out the work W before printing, and a take-up roller 22 that takes up the work W after printing. The feed roller 21 is disposed at the rear lower part of the device frame 10, and is a take-up shaft for the feed roll WA, which is a wound body of the work W before printing. The take-up roller 22 is disposed at the front lower part of the device frame 10, and is a take-up shaft for the take-up roll WB, which is a wound body of the work W after the printing process. A first motor M1 is attached to the take-up roller 22, which drives the take-up roller 22 to rotate about its axis and executes the operation of winding up the work W.

[0016] The path between the delivery roller 21 and the take-up roller 22 and passing through the printing area 12 is the transport path for the work W. On this transport path, a first tension roller 23, a work guide 24, a transport roller 25 and a pinch roller 26, a turn-back roller 27, and a second tension roller 28 are arranged in this order from the upstream side. The first tension roller 23 applies a predetermined tension to the work W on the upstream side of the transport roller 25. The work guide 24 changes the transport direction of the work W from the upward direction to the forward direction, and allows the work W to enter the printing area 12.

[0017] The transport roller 25 generates a transport force that intermittently transports the work W in the printing area 12. The transport roller 25 is driven to rotate around its axis by the second motor M2. The transport roller 25 transports the work W intermittently forward (in the transport direction F) so that the work W passes through the printing area 12 facing the carriage 3. The pinch roller 26 is disposed so as to face the transport roller 25 from above, and forms a transport nip with the transport roller 25. The turn-back roller 27 changes the transport direction of the work W that has passed through the printing area 12 from the forward direction to the downward direction, and guides the work W after the printing process to the winding roller 22. The second tension roller 28 applies a predetermined tension to the work W downstream of the transport roller 25. A platen 29 is disposed below the transport path of the work W in the printing area 12.

[0018] The carriage 3 is supported at one end by the guide rail 17 and moves back and forth in the main scanning direction (left and right direction) intersecting with the transport direction F. The carriage 3 includes a carriage frame 30, and an ink head 4, a pre-processing head 5, a post-processing head 6, and a sub-tank (not shown) mounted on the carriage frame 30. The carriage frame 30 includes a head support frame 31 and a back frame 32. The head support frame 31 is a horizontal plate that holds the heads 4 to 6 described above. The back frame 32 is a vertical plate that extends upward from the rear end edge of the head support frame 31. A timing belt 16 is fixed to the back frame 32, and the guide rail 17 is engaged therewith.

[0019] [Carriage Details] The carriage 3 will now be described in further detail. Fig. 3 is an enlarged perspective view of the carriage 3 shown in Fig. 1, with a maintenance unit 7 also shown. Fig. 3 shows the transport direction F (sub-scanning direction) of the work W and the main scanning direction S which is the moving direction of the carriage 3. Fig. 3 shows an example in which a plurality of ink heads 4 which eject ink for image formation onto the work W, and a pre-treatment head 5 and a post-treatment head 6 which eject non-color-forming treatment liquid are mounted on the carriage 3. An actual carriage 3 is also equipped with a plurality of sub-tanks which supply the ink and treatment liquid to these heads 4, 5, and 6.

[0020] Each of the ink heads 4 includes a number of nozzles that eject ink droplets by an ejection method such as a piezo method using a piezo element or a thermal method using a heating element, and ink passages that guide ink to the nozzles. For example, a water-based pigment ink containing a water-based solvent, pigment, and binder resin can be used as the ink. In this embodiment, the multiple ink heads 4 include first to eighth ink heads 4A to 4H that eject eight different colors of ink, respectively.

[0021] The ink heads 4A to 4H of each color are mounted on the head support frame 31 of the carriage 3 so as to be aligned in the main scanning direction S. Each of the ink heads 4A to 4H of each color has two heads. For example, the first ink head 4A is composed of an upstream head 4A1 arranged on the upstream side of the transport direction F, and a downstream head 4A2 arranged downstream of the upstream head 4A1 and shifted to the left in the main scanning direction S. The ink heads 4B to 4H of the other colors are arranged in the same manner. Each of the upstream heads of these ink heads 4B to 4H is aligned in a row in the main scanning direction S at the same position as the upstream head 4A1 in the transport direction F, and each of the downstream heads is aligned in a row in the main scanning direction S at the same position as the downstream head 4A2 in the transport direction F.

[0022] The pre-treatment head 5 (treatment liquid head) and post-treatment head 6 are arranged at a different position from the ink heads 4 in the transport direction F. The pre-treatment head 5 is arranged upstream of the ink heads 4 in the transport direction F. FIG. 3 shows an example in which one pre-treatment head 5 is arranged near the left end of the array of ink heads 4. In contrast, the post-treatment head 6 is arranged downstream of the ink heads 4 in the transport direction F. FIG. 3 shows an example in which two post-treatment heads 6A, 6B are arranged side by side in the main scanning direction S near the right end of the array of ink heads 4.

[0023] The pretreatment head 5 ejects a pretreatment liquid for performing a predetermined pretreatment on the workpiece W. The pretreatment liquid is ejected from the pretreatment head 5 onto a position on the workpiece W where ink has not yet been ejected from the ink head 4. The pretreatment liquid is a non-coloring treatment liquid that does not develop color even when attached to the workpiece W, and is a treatment liquid that exhibits functions such as increasing the fixation of ink to the workpiece W and the coagulation of ink pigments. As such a pretreatment liquid, a treatment liquid in which a binder resin is blended into a solvent, or a treatment liquid in which a positively charged cationic resin is blended into a solvent, can be used.

[0024] The post-treatment head 6 ejects a post-treatment liquid for performing a predetermined post-treatment on the workpiece W to which the ink has been attached. The post-treatment liquid is ejected from the post-treatment head 6 to a position on the workpiece W after the ink has been ejected from the ink head 4. The post-treatment liquid is a non-coloring treatment liquid that does not develop color even when it adheres to the workpiece W, and is a treatment liquid that exhibits a function of enhancing the fixability and robustness of the ink image printed on the workpiece W by the ink head 4. The robustness means resistance to rubbing and scraping. As such a post-treatment liquid, a silicone-based treatment liquid or the like can be used.

[0025] Here, the non-coloring treatment liquid refers to a treatment liquid that is not recognized as colored by the naked eye when printed alone on a recording medium. The color here includes colors with a saturation of 0, such as black, white, and gray. The non-coloring treatment liquid is basically a transparent liquid, but when, for example, 1 liter of treatment liquid is viewed in liquid form, it is not completely transparent and may appear slightly white. Such a color is very light, so when printed alone on a recording medium, it is not recognized as colored by the naked eye. Note that, depending on the type of treatment liquid, when printed alone on a recording medium, a change such as glossiness may occur on the recording medium, but such a state is not colored.

[0026] Openings 31H are provided at the locations of the heads in the head support frame 31. The ink heads 4A to 4F, the pre-treatment head 5, and the post-treatment head 6 are attached to the head support frame 31 so as to be fitted into the respective openings 31H. Nozzles arranged on the lower end surface of each of the heads 4, 5, and 6 are exposed from each opening 31H.

[0027] As described above, the inkjet printer 1 according to this embodiment is an all-in-one printer in which three types of heads, the ink head 4, the pre-treatment head 5, and the post-treatment head 6, are mounted on a single carriage 3. With this printer 1, for example, in the printing process of performing inkjet printing on fabric in digital textile printing, the process of ejecting the pre-treatment liquid and the process of ejecting the post-treatment liquid can be executed integrally. This makes it possible to simplify the textile printing process and make the textile printing device more compact.

[0028] [Maintenance unit outline] 4 is a schematic cross-sectional view along the front and rear of the carriage 3 and the maintenance unit 7. The maintenance unit 7 includes a container unit 70, a wiping unit 8, and a cleaning unit 9. The maintenance area 13 (FIG. 1) is an area where processes are performed to unclog the nozzles of the heads 4, 5, and 6 and to remove dirt and the like from the nozzle arrangement surface NA of the heads 4, 5, and 6. For this process, a purging operation, a wiping operation, and a cleaning operation are performed in the maintenance area 13.

[0029] The purging operation is an operation forcibly ejecting pressurized ink, pre-treatment liquid, and post-treatment liquid from the ink head 4, pre-treatment head 5, and post-treatment head 6, respectively. The container unit 70 collects the ink, pre-treatment liquid, and post-treatment liquid ejected from the heads 4, 5, and 6 during the purging operation. The wiping operation is an operation for wiping the nozzle array surface NA with a wiper equipped with a wiping member such as a blade. The wiping unit 8 is a unit that performs the wiping operation. The cleaning operation is an operation for cleaning the wiping unit 8 that has become contaminated by performing the wiping operation. The cleaning unit 9 is a unit that performs the cleaning operation. The container unit 70 also collects the cleaning liquid used in the cleaning operation.

[0030] The container unit 70 has a structure for separately collecting the pre-treatment liquid, ink, and post-treatment liquid. In this embodiment, as described above, a treatment liquid that improves the fixability of the ink and the coagulation property of the ink pigment is used as the pre-treatment liquid. Therefore, when the pre-treatment liquid and the ink are mixed, the mixed liquid will coagulate, which may cause problems in collecting the mixed liquid in the waste liquid tank. On the other hand, the post-treatment liquid used in this embodiment will not coagulate even when mixed with the ink. This is the reason for the above-mentioned separate collection in the container unit 70.

[0031] The container unit 70 includes an ink container 71, a pre-treatment liquid container 72 (treatment liquid container), and a cleaning liquid tray 73. The ink container 71 is a container that collects the ink and post-treatment liquid ejected from the ink head 4 and the post-treatment head 6, respectively, in the purging operation. The ink container 71 includes a first opening 71H on its upper surface that receives the ink and post-treatment liquid. The first opening 71H opens upward at a position that faces at least the nozzle array surface NA of the ink head 4 and the post-treatment head 6 in the vertical direction. The ink container 71 also collects the ink and post-treatment liquid wiped from the nozzle array surface NA in the wiping operation.

[0032] The pre-treatment liquid container 72 is disposed at a position covering a part of the upper side of the first opening 71H. The pre-treatment liquid container 72 is a container that collects the pre-treatment liquid discharged from the pre-treatment head 5 in the purging operation. The pre-treatment liquid container 72 has a second opening 72H on its upper surface that receives the pre-treatment liquid. The second opening 72H opens upward at a position that faces at least the nozzle arrangement surface NA of the pre-treatment head 5 in the vertical direction. The pre-treatment liquid container 72 also collects the pre-treatment liquid wiped off from the nozzle arrangement surface NA in the wiping operation. The cleaning liquid tray 73 is a container that collects the cleaning liquid 9A sprayed from the cleaning liquid cleaning unit 9 in the cleaning operation.

[0033] The container unit 70 includes an overflow passage 741, a treatment liquid passage 742, and a relay passage 743 for the circulation of the collected liquid. The overflow passage 741 has a start opening on the bottom surface of the ink container 71, and a terminal end leading to a waste liquid container (not shown). The treatment liquid passage 742 has a start opening near the bottom surface of the pretreatment liquid container 72, and a terminal end leading to the waste liquid container. The relay passage 743 has a start opening on the bottom surface of the cleaning liquid tray 73, and a terminal opening near the bottom surface of the ink container 71. That is, the cleaning liquid 9A collected in the cleaning liquid tray 73 is first introduced into the ink container 71, and then collected into the waste liquid container through the overflow passage 741.

[0034] Note that "receiving" the liquid here means receiving the liquid that falls from above. Liquid flows into the ink container 71 from the cleaning liquid tray 73 through the relay passage 743, but this is not included in the above-mentioned "receiving". The liquid flowing from the cleaning liquid tray 73 contains small amounts of ink, pre-treatment liquid, and post-treatment liquid in addition to the cleaning liquid. However, since the concentration of the pre-treatment liquid is low, it does not substantially solidify even if it enters the ink container 71. Note that a partition may be provided in the cleaning liquid tray 73 so that only liquid that does not contain the pre-treatment liquid flows into the ink container 71.

[0035] A cap rubber 75 is attached to the upper surface 70A of the container unit 70. The cap rubber 75 is arranged so as to surround the periphery of the first opening 71H of the ink container 71. The carriage 3 is capable of moving in the vertical direction as indicated by the arrow A1 in the figure. When the carriage 3 is in standby mode in the maintenance area 13 or when the printer 1 is at rest, the carriage 3 is lowered and the lower surface 311 of the head support frame 31 comes into contact with the cap rubber 75. This seals the nozzle array surface NA of the heads 4, 5, and 6.

[0036] The wiping unit 8 includes a wiper support plate 81 (support plate), and an ink wiper 82, a pre-treatment liquid wiper 83 (treatment liquid wiper), and a post-treatment liquid wiper 84 supported by the wiper support plate 81. The wiping unit 8 is capable of moving in the front-rear direction as indicated by the arrow A2 in the figure. The wiper support plate 81 is a flat plate-shaped member, and moves in the front-rear direction between the carriage 3 and the cleaning unit 9, and the container unit 70. The ink wiper 82 wipes the nozzle arrangement surface NA of the ink head 4 by moving in the rear direction while in contact with the nozzle arrangement surface NA of the ink head 4. Similarly, the pre-treatment liquid wiper 83 and the post-treatment liquid wiper 84 wipe the nozzle arrangement surfaces NA of the pre-treatment head 5 and the post-treatment head 6, respectively.

[0037] The cleaning unit 9 includes a nozzle holding plate 91 and a plurality of cleaning nozzles 92 held by the nozzle holding plate 91. The nozzle holding plate 91 is made of a flat member and is fixedly disposed so as to face the cleaning liquid tray 73 of the container unit 70. The plurality of cleaning nozzles 92 are disposed at positions corresponding to the ink wiper 82, the pre-processing liquid wiper 83, and the post-processing liquid wiper 84 attached to the wiper support plate 81. That is, when the wiping unit 8 moves to a predetermined position directly below the cleaning unit 9, the plurality of cleaning nozzles 92 are held by the nozzle holding plate 91 at positions facing the wipers 82, 83, and 84 from above. The cleaning nozzles 92 spray the cleaning liquid 9A in a fan-shaped spray. The cleaning liquid 9A is supplied to the cleaning nozzles 92 from a cleaning liquid tank (not shown) via a cleaning liquid hose 93.

[0038] [Control configuration] 5 is a block diagram showing part of the control configuration of the printer 1. The printer 1 includes a controller 33, a carriage drive motor 34, a carriage lift motor 35, a wiper movement motor 36, a cleaning water supply pump 37, and a head drive unit 38, the operations of which are controlled by the controller 33.

[0039] The carriage drive motor 34 generates a driving force for moving the carriage 3 in the left-right direction within the range of the turn-back area 14, the printing area 12, and the maintenance area 13 (FIG. 1). The carriage drive motor 34 drives the timing belt 16 (FIGS. 1 to 3). The carriage lift motor 35 generates a driving force for moving the carriage 3 in the up-down direction in the maintenance area 13. The wiper movement motor 36 generates a driving force for moving the wiping unit 8 in the front-rear direction. The cleaning water supply pump 37 is connected to the cleaning liquid hose 93, and supplies the cleaning liquid 9A to the cleaning nozzle 92 at a predetermined pressure. The head drive unit 38 executes the ejection operation of the ink, pre-treatment liquid, and post-treatment liquid from each of the heads 4, 5, and 6.

[0040] When performing the purging operation, the controller 33 controls the wiper movement motor 36 to move the wiping unit 8 backward to a retracted position below the cleaning unit 9. Next, the controller 33 controls the head drive unit 38 to eject the ink, pre-treatment liquid, and post-treatment liquid at high pressure from each of the heads 4, 5, and 6 to clean the nozzles. The ink and post-treatment liquid ejected in the purging operation are collected in an ink container 71, and the pre-treatment liquid is collected in a pre-treatment liquid container 72.

[0041] When performing the wiping operation, the controller 33 controls the wiper movement motor 36 to move the wiping unit 8 to the frontmost wiping start position. Next, the controller 33 controls the carriage lift motor 35 to lower the nozzle arrangement surface NA of each of the heads 4, 5, 6 to a height position where the nozzle arrangement surface NA contacts the wipers 82, 83, 84 of the wiping unit 8. Thereafter, the controller 33 moves the wiping unit 8 backward. The ink and post-treatment liquid wiped from the nozzle arrangement surface NA by wiping with the ink wiper 82 and the post-treatment liquid wiper 84 are collected in the ink container 71. In addition, the pre-treatment liquid wiped from the nozzle arrangement surface NA by wiping with the pre-treatment liquid wiper 83 is collected in the pre-treatment liquid container 72.

[0042] When performing the cleaning operation, the controller 33 controls the wiper movement motor 36 to move the wiping unit 8 backward to a retracted position below the cleaning unit 9. Next, the controller 33 controls the cleaning water supply pump 37 to supply cleaning liquid 9A to the cleaning nozzle 92 via the cleaning liquid hose 93. As a result, the cleaning liquid 9A is sprayed onto each of the wipers 82, 83, and 84 of the wiping unit 8, and foreign matter attached by wiping is removed. The cleaning liquid 9A is collected in the cleaning liquid tray 73.

[0043] [Detailed structure of the maintenance unit] Next, one specific embodiment of the above-mentioned maintenance unit 7 will be illustrated, and its detailed structure will be described. Fig. 6 is an overall perspective view of the maintenance unit 7, Fig. 7 is a perspective view of a state in which the cleaning unit 9 has been removed from Fig. 6, Fig. 8A is a perspective view of a state in which the wiping unit 8 has been further removed from the state in Fig. 7, and Fig. 8B is an enlarged view of the vicinity of the pre-treatment liquid container 72 in Fig. 8A. Figs. 6 and 7 show a standby state waiting for a wiping command or a state in which the cleaning operation is performed, in which the wiping unit 8 has been moved to the rearmost side.

[0044] As described above, the maintenance unit 7 includes the container unit 70, the wiping unit 8, and the cleaning unit 9. The container unit 70 is attached to the apparatus frame 10 (FIG. 1) so as to be able to be pulled out forward in the maintenance area 13. The wiping unit 8 is assembled so as to be able to move in the front-rear direction relative to the container unit 70. The cleaning unit 9 is fixedly assembled to the apparatus frame 10.

[0045] <Container unit> The container unit 70 includes a frame structure 700 having a rectangular parallelepiped shape that is somewhat elongated in the front-rear direction, an ink container 71 and a pretreatment liquid container 72 disposed on the front side of the frame structure 700, and a cleaning liquid tray 73 disposed on the rear side of the frame structure 700. The frame structure 700 includes a pair of left and right side frames 701 extending in the front-rear direction, and a front frame 702 connecting front ends of these side frames 701 to each other.

[0046] A handle 703 for pulling out the container unit 70 forward is attached to the front frame 702. A plurality of waste liquid hoses 704 are pulled out from the lower part of the front frame 702. The waste liquid hoses 704 connect an overflow passage 741 communicating with the cavity of the ink container 71, a treatment liquid passage 742 communicating with the cavity of the pretreatment liquid container 72, and a waste liquid tank (not shown). A slider 705 is attached to the outer surface of the pair of side frames 701. The slider 705 engages with a guide rail (not shown) fixed to the device frame 10, and enables the container unit 70 to be pulled out forward from the device frame 10. A chain protector 706 for accommodating electric cables and hoses is provided below the frame structure 700. The chain protector 706 is deformed in response to the pulling out of the container unit 70.

[0047] The ink container 71 is a tray-shaped container having a rectangular first opening 71H on the top surface, the first opening 71H being long in the left-right direction. The ink container 71 includes a rectangular bottom surface 711 long in the left-right direction, four tapered surfaces 712 extending upward from the four edges of the bottom surface 711, and an upper end flange 708 formed on the periphery of the first opening 71H. The ink container 71 is a separate entity from the frame structure 700 and is fitted into the frame structure 700. The upper end flange 708 of the ink container 71 is supported by the side frame 701 and the front frame 702. From the bottom surface 711, a start end opening of an overflow passage 741 protrudes upward by a predetermined length. From the vicinity of the lower end of the tapered surface 712 on the left side, a terminal end opening of a relay passage 743 protrudes.

[0048] The size of the first opening 71H in the left-right direction is approximately equal to the distance between the pair of side frames 701. The size of the first opening 71H in the front-rear direction is slightly larger than half the front-rear width of the container unit 70. A cap rubber 75 arranged to surround the periphery of the first opening 71H is attached to the upper surface of the upper end flange 708. The upper end flange 708 corresponds to the upper surface 70A shown in the schematic diagram of FIG. 4. The head support frame 31 of the carriage 3 has a size larger than the area surrounded by the cap rubber 75. On the other hand, the arrangement area of ​​the heads 4, 5, and 6 held by the head support frame 31 is a size slightly smaller than the size of the first opening 71H. The cap rubber 75 abuts against the lower surface 311 of the head support frame 31 on the outer periphery of the arrangement area of ​​the heads 4, 5, and 6, and seals the nozzle arrangement surface NA of the heads 4, 5, and 6.

[0049] 8A and 8B, the pretreatment liquid container 72 is disposed at a position on the left rear side of the ink container 71 so as to cover a part of the first opening 71H. The position of the pretreatment liquid container 72 is a position directly facing the pretreatment head 5 held by the carriage 3 during wiping. For example, if the pretreatment head 5 is disposed near the center or right end of the head support frame 31, the pretreatment liquid container 72 is also disposed at a position corresponding thereto. The pretreatment liquid container 72 has a rectangular second opening 72H on its upper surface that is elongated in the front-rear direction so as to correspond to the shape of the nozzle array surface NA of the pretreatment head 5. In this embodiment, the second opening 72H is located at the same height as the first opening 71H. In other words, the second opening 72H occupies a part of the area of ​​the original first opening 71H.

[0050] The pre-treatment liquid container 72 is formed by a front wall 721, a rear wall 722, a right wall 723, and a left wall 724. Of these walls, the rear wall 722 utilizes a portion near the upper end of the rear tapered surface 712 of the ink container 71, and the left wall 724 utilizes a portion near the upper end of the left tapered surface 712. The front wall 721 is a wall that is near the upper end of the left tapered surface 712 and protrudes to the right from near the center in the front-to-rear direction. The right wall 723 is a wall that connects the right edges of the front wall 721 and the rear wall 722. The right wall 723 stands upright in a substantially vertically upward direction from the left tapered surface 712, which is inclined downward and to the right.

[0051] The cleaning liquid tray 73 is a container that has a rectangular top opening that is long in the left-right direction, and is shallower than the ink container 71. The bottom surface of the cleaning liquid tray 73 includes an inclined surface 731 and a liquid collection surface 732. The inclined surface 731 is a surface that slopes gently downward from the right end side to the left end side of the cleaning liquid tray 73. The liquid collection surface 732 is located near the left end of the cleaning liquid tray 73, and is a flat surface that forms the deepest part of the bottom surface. The left edge of the inclined surface 731 is continuous with the right edge of the liquid collection surface 732. The starting end of a relay passage 743 opens into the liquid collection surface 732.

[0052] <Wiping unit> As shown in Fig. 7, the wiping unit 8 includes a wiper support plate 81, an ink wiper 82, a pre-treatment liquid wiper 83, a post-treatment liquid wiper 84, and a wiper drive section 85. The upper diagram in Fig. 9 is a plan view of the wiper support plate 81 holding the wipers 82, 83, and 84, and the lower diagram in Fig. 9 is a plan view showing the arrangement of the ink head 4, pre-treatment head 5, and post-treatment head 6 mounted on the carriage 3, and showing the corresponding relationship with the wipers 82, 83, and 84. The arrangement of the heads 4, 5, and 6 shown in the lower diagram in Fig. 9 is the same as the arrangement exemplified previously in Fig. 3.

[0053] The wiper support plate 81 is formed by punching a thin flat plate member, and has a plurality of rectangular convex plates 811. The plurality of convex plates 811 protrude in the rear direction, which is the moving direction during wiping. Between adjacent convex plates 811, a recess 812 recessed in the front side is formed. Ink wipers 82 for wiping the nozzle array surface NA of the ink head 4 are attached to the end edge (rear end) of the convex plate 811 and the end edge of the recess 812. The ink wipers 82 arranged on the end edge of the convex plate 811 are for wiping the upstream head of the ink head 4 of each color, such as the ink wiper 82A1 arranged for the upstream head 4A1 of the first ink head 4A. On the other hand, the ink wipers 82 arranged on the end edge of the recess 812 are for wiping the downstream head of the ink head 4 of each color, such as the ink wiper 82A2 arranged for the downstream head 4A2.

[0054] In the wiper support plate 81, a support region that supports the pretreatment liquid wiper 83 that wipes the nozzle arrangement surface NA of the pretreatment head 5 is disposed at a position that protrudes rearward in the movement direction during wiping compared to other regions of the wiper support plate 81. Specifically, a convex piece 814 extends further rearward from the rear end of the leftmost convex plate 811. The pretreatment liquid wiper 83 is attached to the edge (rear end) of the convex piece 814. A window portion 815 corresponding to the recess 812 is provided on the front side of the convex piece 814. In this way, by disposing the pretreatment liquid wiper 83 to be supported at the position that protrudes most in the movement direction on the wiper support plate 81, the pretreatment liquid wiped by the pretreatment liquid wiper 83 is less likely to adhere to other parts of the wiper support plate 81 during wiping.

[0055] As shown in the lower diagram of FIG. 9, in this embodiment, the pre-treatment head 5 and the downstream head 4A2 of the first ink head 4A are arranged at positions where they completely overlap each other in the movement direction (rear direction) during wiping. That is, the pre-treatment head 5 and the downstream head 4A2 are arranged side by side on the upstream side and the downstream side in the transport direction F at the same position in the left-right direction of the head support frame 31. With such an arrangement, the path through which the ink wiper 82A2 passes when moving from the wiping area to the cleaning unit 9 overlaps with the path wiped by the pre-treatment liquid wiper 83. Therefore, it is possible to reduce the risk of the pre-treatment liquid dripping onto the ink wiper 82A2 and causing aggregation. Note that it is preferable that the pre-treatment head 5 and the downstream head 4A2 are arranged in a positional relationship where they completely overlap each other in the movement direction during wiping, but they may be arranged with a slight shift in the left-right direction.

[0056] The right end side of the wiper support plate 81 is a support area that supports a post-processing liquid wiper 84 that wipes the nozzle array surface NA of the post-processing head 6. Two post-processing heads 6A, 6B are arranged side by side in the main scanning direction near the right end of the head support frame 31. The post-processing head 6A on the left side is arranged side by side with the upstream head 4G1 of the seventh ink head 4G, and the post-processing head 6B on the right side is arranged side by side with the upstream head 4H1 of the eighth ink head 4H, respectively, on the upstream and downstream sides of the transport direction F.

[0057] Corresponding to such a head arrangement, the wiper support plate 81 is provided with a pair of holding pieces 816 and a window portion 817 near its right end. The holding piece 816 supports ink wipers 82G1, 82H1 that wipe the upstream heads 4G1, 4H1 at its rear edge. Ink wipers 82G2, 82H2 that wipe the downstream heads 4G2, 4H2 are supported at the edge of the recess 812 adjacent to the left side of each holding piece 816. The window portion 817 is an opening disposed in front of the holding piece 816. The post-processing liquid wipers 84 (84A, 84B) that wipe the post-processing heads 6A, 6B are supported at the opening edge on the front side of the window portion 817.

[0058] The wiper support plate 81 has a plurality of protruding portions 813 arranged corresponding to each of the wipers 82, 83, and 84 described above. The protruding portions 813 are connected to the rear end of the protruding plate 811, the base end edge of the recess 812, the rear end of the protruding piece 814, and the base end edge of the window portion 817. These protruding portions 813 are small projections that protrude in the movement direction during wiping when viewed from above. The wipers 82, 83, and 84 are arranged on the protruding portions 813 that are respectively associated with them. With such an arrangement, it is possible to make it difficult for ink or treatment liquid adhering to the wipers 82, 83, and 84 to adhere to the wiper support plate 81.

[0059] 10 is a perspective view showing a detailed structure of the ink wiper 82. The pre-treatment liquid wiper 83 and the post-treatment liquid wiper 84 also have a structure similar to that of the ink wiper 82 shown here. The ink wiper 82 includes a wiper blade 821 (ink blade or treatment liquid blade), a first holder 822, and a second holder 823.

[0060] The wiper blade 821 is a plate material that actually comes into contact with the nozzle array surface NA to perform wiping. The upper end of the wiper blade 821 is located at a position that protrudes upward from the upper surface of the wiper support plate 81. The first holder 822 and the second holder 823 are members that sandwich and hold the wiper blade 821. The first holder 822 is fitted into a recess provided in the protruding portion 813 and fixed with a screw, and supports the lower back surface of the wiper blade 821. The second holder 823 is attached to the lower front surface of the wiper blade 821.

[0061] The second holder 823 has a pair of openings 824, and the wiper blade 821 also has a through hole at the same position as the opening 824. Meanwhile, the first holder 822 has a pair of claws 825. The claws 825 are inserted through the through holes and the opening 824, and engage the second holder 823 at the periphery of the opening 824. Due to this engagement force, the wiper blade 821 is sandwiched between the first holder 822 and the second holder 823. The wiper blade 821 is held at a position protruding further than the protruding end face of the convex portion 813.

[0062] The pre-treatment liquid wiper 83 and the post-treatment liquid wiper 84 may be configured to have the same structure, shape, and material as the ink wiper 82 shown in FIG. 10, or may be configured to have different structures, shapes, and materials. For example, the shape and material of the wiper blade 821 and the support structure of the wiper blade 821 may be different from those of the ink wiper 82 for the pre-treatment liquid wiper 83 and / or the post-treatment liquid wiper 84 depending on the properties of the ink and treatment liquid. A blade made of a rubber or resin material having a predetermined rigidity is used as the wiper blade 821. For example, assume that the pre-treatment liquid has a property of drying faster than the ink and is relatively difficult to wipe. In this case, it is desirable to increase the wiping power by using a blade having a higher rigidity than that of the ink wiper 82 as the wiper blade 821 of the pre-treatment liquid wiper 83 or increasing the protruding height of the wiper blade 821.

[0063] 11A is a perspective view of the maintenance unit 7 from a different perspective direction than in FIG. 7, and is a view for explaining the wiper driving unit 85. FIG. 11B is an enlarged view of a portion XIB surrounded by a dotted line in FIG. 11A. The wiper driving unit 85 is a mechanism for moving the wiper support plate 81 holding the wipers 82, 83, and 84 in the front-rear direction. The wiper driving unit 85 includes a servo motor 851, a ball screw 852, and a slider 853. The servo motor 851 is a motor corresponding to the wiper moving motor 36 shown in FIG. 5.

[0064] The servo motor 851 generates a driving force for moving the wiper support plate 81. The servo motor 851 is attached to the right end of the rear plate 707 of the container unit 70. The ball screw 852 is driven to rotate forward or backward around its axis by the servo motor 851. The ball screw 852 extends in the front-rear direction along the right side frame 701. A guide bar (not shown) extending in the front-rear direction is attached to the left side frame 701. The slider 853 includes a nut member screwed into the ball screw 852. When the ball screw 852 rotates forward or backward, the slider 853 moves forward or backward along the ball screw 852.

[0065] The slider 853 is connected to the wiper support plate 81. A connecting plate 818 made of a long, thin flat member is attached to the upper part of the slider 853. A right end 81E of the wiper support plate 81 is placed on this connecting plate 818, and the two are fastened together with a fixing screw 819. Although not shown in the figure, the left end of the wiper support plate 81 is also supported by the same member as the connecting plate 818 and the slider 853, and is guided along the guide bar.

[0066] The movement range of wiper support plate 81 is between the front end (wiping area) and the rear end (cleaning area) of container unit 70. For example, when servo motor 851 is driven to rotate forward by controller 33, slider 853 is sent forward, and wiper support plate 81 fixed to slider 853 also moves forward. On the other hand, when servo motor 851 is driven to rotate reversely, wiper support plate 81 moves rearward.

[0067] <Cleaning unit> 6, the cleaning unit 9 includes a nozzle holding plate 91 and a plurality of cleaning nozzles 92. The nozzle holding plate 91 is a U-shaped frame material including a top plate 911 and a pair of left and right side plates 912. The top plate 911 is a flat plate having a width slightly larger than the left and right width of the container unit 70. The pair of side plates 912 are flat plates hanging down from the left and right ends of the top plate 911, and face the left and right side frames 701, respectively.

[0068] The nozzle holding plate 91 is fixed at a suitable position on the apparatus frame 10 (FIG. 1). When the container unit 70 is loaded at a predetermined position on the apparatus frame 10, the nozzle holding plate 91 is positioned so as to be fitted from above into the rear region of the container unit 70. The portion where the nozzle holding plate 91 covers the container unit 70 becomes a cleaning area for cleaning the ink wiper 82, the pre-processing liquid wiper 83, and the post-processing liquid wiper 84. The top plate 911 faces the cleaning liquid tray 73 of the container unit 70 in the vertical direction with a predetermined gap therebetween. The gap has a vertical width that allows the wiping unit 8 to enter between the top plate 911 and the cleaning liquid tray 73.

[0069] The multiple cleaning nozzles 92 are disposed at appropriate positions on the top plate 911 so as to match the arrangement of the wipers 82, 83, and 84 on the wiper support plate 81. The multiple cleaning nozzles 92 include a nozzle 92A for cleaning the ink wiper 82, a nozzle 92B for cleaning the pre-processing liquid wiper 83, and a nozzle 92C for cleaning the post-processing liquid wiper 84. These nozzles 92A, 92B, and 92C eject the cleaning liquid 9A in a fan-shaped spray form from their respective bottom end surfaces (see FIG. 4) to clean the wipers 82, 83, and 84.

[0070] [Wipe movement path] Next, the movement path during wiping will be described, including the positional relationship of the wiping unit 8 with respect to the surrounding members. Fig. 12 is a perspective view showing the initial position of the wiping unit 8 during wiping. During wiping, the wiping unit 8 moves backward from the initial position so as to head toward the cleaning area where the cleaning unit 9 is arranged. The wiping area where the wipers 82, 83, and 84 wipe the heads 4, 5, and 6 is located above the first opening 71H of the ink container 71 and the second opening 72H of the pre-treatment liquid container 72.

[0071] To the left of the maintenance unit 7 is a printing area 12 (FIG. 1) where an image is formed by discharging ink from the ink head 4. For this reason, when the carriage 3 makes a pit stop in the maintenance area 13, it enters from the left side of the maintenance unit 7. As shown in FIG. 9, the pretreatment head 5 is supported by the carriage 3 at the leftmost position alongside the downstream head 4A2 of the first ink head 4A. Accordingly, the pretreatment liquid wiper 83 is also disposed at the leftmost position on the wiper support plate 81.

[0072] That is, in the movement direction in which the carriage 3 moves from the printing area 12 to the wiping area, the pretreatment liquid wiper 83 is disposed at a position closer to the printing area 12 than the other ink wipers 82, except for the ink wiper 82A2 for the downstream head 4A2. With this arrangement, the pretreatment liquid container 72 is naturally disposed near the left end of the ink container 71. In this case, it is possible to realize an arrangement in which the pretreatment head 5 does not pass through the first opening 71H of the ink container 71 during the pit-in. This makes it possible to make it difficult for the pretreatment liquid adhering to the pretreatment head 5 to drip into the ink container 71.

[0073] Further, the pretreatment liquid wiper 83 is supported by the wiper support plate 81 at a position closest to the cleaning area among the wipers 82, 83, and 84 in the moving direction from the wiping area to the cleaning area. That is, as shown in the upper diagram of Fig. 9, the pretreatment liquid wiper 83 is disposed on the edge of the convex piece 814 that protrudes furthest backward in the wiper support plate 81 when viewed from above. This allows the pretreatment liquid wiper 83 to be introduced into the cleaning area as quickly as possible for cleaning treatment. For example, in the case where the pretreatment liquid has a quick-drying property, if the nozzle 92B (Fig. 6) for cleaning the pretreatment liquid wiper 83 is disposed on the most forward side of the nozzle holding plate 91, the pretreatment liquid wiper 83 can be immediately cleaned.

[0074] Fig. 13 is a top view of the maintenance unit 7, showing the movement path MW of the wiping unit 8 during wiping. The position indicated by the dotted line in the figure is the initial position during wiping of the wiping unit 8 and the pre-treatment liquid wiper 83. The position of the wiping unit 8 indicated by the solid line in Fig. 13 is the wiping completion position where the wipers 82, 83, and 84 are cleaned, and is also a standby position where an instruction to perform a wiping operation is awaited.

[0075] In this embodiment, the movement path MW (movement range) of the pretreatment liquid wiper 83 during wiping is set to a position that avoids being directly above the first opening 71H of the ink container 71. Specifically, the movement range of the pretreatment liquid wiper 83 when performing wiping in the wiping area is set to be directly above the second opening 72H of the pretreatment liquid container 72. In other words, the first opening 71H does not substantially exist directly below the area where the pretreatment liquid wiper 83 wipes the nozzle array surface NA of the pretreatment head 5, and most or all of the area is arranged to face the second opening 72H in the vertical direction. In other words, the first opening 71H of the ink container 71 is arranged at a position other than the area where the pretreatment liquid wiper 83 wipes the nozzle array surface NA when viewed from above. This arrangement can reduce the occurrence of the pretreatment liquid wiped by the pretreatment liquid wiper 83 entering the ink container 71 through the first opening 71H during wiping. Therefore, the occurrence of chemical reactions such as ink aggregation can be suppressed.

[0076] When the ink container 71 and the pretreatment liquid container 72 are viewed in a direction (front-rear direction) along the moving path MW, it can be said that a part of the first opening 71H (left end front part) and the second opening 72H are arranged in series (see FIG. 13). That is, a part of the first opening 71H is on the front side, and the second opening 72H is on the rear side. The orientation direction of the moving path MW, that is, the movement direction of the pretreatment liquid wiper 83, is from the front side to the rear side. In other words, the movement direction of the pretreatment liquid wiper 83 is a direction away from the first opening 71H. Moreover, as shown in FIG. 8B, the rear end edge (rear wall 722) of the pretreatment liquid container 72 is flush with the rear end edge (rear tapered surface 712) of the ink container 71. That is, the first opening 71H is not interposed between the rear end edge of the pretreatment liquid container 72 and the cleaning area in the moving path MW. Therefore, it is possible to reduce the amount of pretreatment liquid that may scatter when the pretreatment liquid wiper 83 finishes wiping the pretreatment head 5 and moves away from the nozzle array surface NA into the ink container 71.

[0077] Moreover, the direction of the movement path MW is the direction in which the cleaning area in which the cleaning unit 9 is arranged is located. Such an arrangement also contributes to measures against scattering of the pretreatment liquid. That is, even if the pretreatment liquid adhering to the pretreatment liquid wiper 83 scatters when the pretreatment liquid wiper 83 moves away from the nozzle array surface NA of the pretreatment head 5, the scatter destination is the cleaning area. In the cleaning area, the scattered pretreatment liquid is diluted with a relatively large amount of cleaning liquid and is collected in the cleaning liquid tray 73. Therefore, an operation in which splashes of the pretreatment liquid are unlikely to enter the ink container 71 can be realized.

[0078] <Avoiding the area directly above the first opening> Variations of the above-mentioned "position that avoids being directly above the first opening 71H" will now be described. Fig. 14A to Fig. 14D are schematic diagrams showing various arrangement examples of the pretreatment liquid container 72 that avoid being directly above the first opening 71H of the ink container 71. Fig. 14A to Fig. 14C are schematic cross-sectional views in the left-right direction of the maintenance unit 7, and Fig. 14D is a top view. The "position that avoids being directly above" includes a position outside the space above the first opening 71H, as well as a position where another member is interposed between a partial area of ​​the first opening 71H and the pretreatment liquid wiper 83.

[0079] Fig. 14A shows an example in which the pretreatment liquid container 72 is disposed at a position that covers a part of the first opening 71H, thereby setting the movement range of the pretreatment liquid wiper 83 to a position that avoids being directly above the first opening 71H. The example in Fig. 14A is similar to the example shown in Fig. 8A above. In this example, while the movement range of the pretreatment liquid wiper 83 is set above the first opening 71H, the second opening 72H of the pretreatment liquid container 72 is disposed below the movement range, thereby achieving "a position that avoids being directly above the first opening 71H".

[0080] FIG. 14B shows an example in which the movement range of the pretreatment liquid wiper 83 is simply set to a position outside the space above the first opening 71H. In this example, the pretreatment liquid container 72 is naturally disposed at a position that does not overlap the first opening 71H in the vertical direction. FIG. 14C shows an example in which another member is interposed between the first opening 71H and the pretreatment liquid wiper 83. The pretreatment liquid container 72 is disposed adjacent to the ink container 71. Meanwhile, the pretreatment liquid wiper 83 is positioned above the first opening 71H in order to wipe the pretreatment head 5 disposed above the first opening 71H. In addition, a guide plate 76 is disposed below the pretreatment liquid wiper 83 in a manner that is inclined downward toward the second opening 72H. The pretreatment liquid wiped from the pretreatment head 5 by the pretreatment liquid wiper 83 is guided to the second opening 72H through the guide plate 76.

[0081] 14D shows an example in which the shape of the ink container 71 is devised to achieve a position that avoids being located directly above the first opening 71H. The ink container 71 has a cutout 713 at a position corresponding to a position below the arrangement area of ​​the pre-treatment head 5. Therefore, the movement range of the pre-treatment liquid wiper 83 is outside the first opening 71H. The pre-treatment liquid container 72 is arranged in the cutout 713.

[0082] <Regarding the positional relationship between the moving range and the second opening> Next, the positional relationship between the movement range of the pretreatment liquid wiper 83 and the second opening 72H of the pretreatment liquid container 72 will be described. FIGS. 15A to 15C are schematic diagrams for explaining the movement range of the pretreatment liquid wiper 83 during wiping operation. FIG. 15A shows an actual wiping range d1 in which the pretreatment liquid wiper 83 actually performs wiping operation. The actual wiping range d1 corresponds to the width of the nozzle arrangement section 51 in which a large number of nozzles that eject the pretreatment liquid are arranged in the pretreatment head 5. That is, d1 is the length from the upstream end (front end) to the downstream end (rear end) of the nozzle arrangement section 51 in the movement direction of the pretreatment liquid wiper 83. The nozzle arrangement section 51 is the portion to which the pretreatment liquid actually adheres. Therefore, the period during which the pretreatment liquid wiper 83 moves through the actual wiping range d1 is the section in which the pretreatment liquid wiper 83 (wiper blade 821) actually performs the work of wiping off the pretreatment liquid. When wiping is performed, the wiped pretreatment liquid drips from the wiper blade 821 along the second holder 823 (see FIG. 10). The dripped pretreatment liquid is received in the pretreatment liquid container 72.

[0083] 15A shows an example in which the pretreatment liquid container 72 having the second opening 72H with a front-to-rear width that covers the actual wiping range d1 and the thickness of the pretreatment liquid wiper 83 before and after the actual wiping range d1 is disposed below the pretreatment head 5. By disposing the second opening 72H in such a range, it is possible to cover at least the area where the pretreatment liquid is most likely to drip, and therefore it is possible to significantly reduce the possibility that the pretreatment liquid will be mixed into the ink container 71. Note that instead of the example of FIG. 15A, the second opening 72H may have a size that is the same as or slightly larger than the actual wiping range d1.

[0084] 15B shows a container area range d2 from the start position of the actual wiping until the pretreatment liquid wiper 83 leaves the wiping area. The start position of the actual wiping is the upstream end of the nozzle array section 51, as in FIG. 15A. In this embodiment, the wiping area is the range covered by the first opening 71H of the ink container 71, so the position where the wiping area leaves is the rear end edge of the first opening 71H. FIG. 15B shows an example in which a pretreatment liquid container 72A having a second opening 72H that covers such a container area range d2 is disposed below the pretreatment head 5. If the second opening 72H is disposed corresponding to the container area range d2, the pretreatment liquid that drips from the pretreatment liquid wiper 83 while moving toward the cleaning area after the completion of the actual wiping can be collected by the pretreatment liquid container 72A.

[0085] 15C shows the entire range d3 of a predetermined movement path MW (FIG. 13) along which the pre-processing liquid wiper 83 moves when performing wiping. The rear end of the movement path MW is the standby position and operation completion position of the pre-processing liquid wiper 83. The front end of the movement path MW is the position to which the pre-processing liquid wiper 83 moves furthest forward in a series of wiping operations. That is, during wiping operation, the pre-processing liquid wiper 83 moves forward from the rear end to the front end of the movement path MW, and after the carriage 3 descends and the nozzle array surface NA is set to a predetermined wiping height, the pre-processing liquid wiper 83 moves back from the front end to the rear end of the movement path MW. Here, an example is shown in which the front end of the movement path MW is forward of the pre-processing head 5, but the front end of the movement path MW may be between the front edge of the pre-processing head 5 and the upstream end of the nozzle array section 51.

[0086] FIG. 15C shows an example in which the pretreatment liquid container 72B having the second opening 72H covering the entire range d3 is disposed below the pretreatment head 5. In this case, the entire movement path MW is set at a position that avoids being directly above the first opening 71H. By disposing the second opening 72H corresponding to such a range d3, the pretreatment liquid can be more reliably collected in the pretreatment liquid container 72B. The pretreatment liquid container 72B has a partition plate 725 at the boundary position between the wiping area and the cleaning area. The rear part of the pretreatment liquid container 72B enters the cleaning area. By providing the partition plate 725, the pretreatment liquid collected in the wiping area can be isolated and collected in an independent path.

[0087] <Ink wiper removal section> Of the multiple ink wipers 82 included in the wiping unit 8, the ink wiper 82A2 (FIG. 9) arranged for the downstream head 4A2 located at the far left side passes over the second opening 72H of the treatment liquid container 72 when the wiping unit 8 moves toward the cleaning area. During this passage, ink adhering to the ink wiper 82A2 may drip into the treatment liquid container 72 and cause coagulation or the like. An example of dealing with this problem is shown in FIGS. 16A and 16B.

[0088] 16A is a schematic side view showing the periphery of the ink wiper 82A2. The wiper blade 821 of the ink wiper 82A2 is supported by a convex portion 813 of the wiper support plate 81 while being held by a first holder 822 and a second holder 823. When the ink wiper 82A2 wipes the downstream head 4A2 of the first ink head 4A, the wiped ink or the like may not completely fall from the lower end of the ink wiper 82A2 and may remain as adhering matter T. In order to reduce the adhering matter T just before the second opening 72H of the pre-treatment liquid container 72, it is desirable to provide a sponge 77 (removal portion).

[0089] FIG. 16B is a perspective view of a main part of the container unit 70 showing the arrangement of the sponge 77. In this embodiment, the second opening 72H is arranged downstream of the first opening 71H in the moving direction of the ink wiper 82A2 to the cleaning area. The sponge 77 is arranged at a height position where it contacts the lower end surface of the ink wiper 82A2 and upstream of the second opening 72H. A support plate 78 is protruding near the upper end of the left tapered surface 712 of the ink container 71 and upstream of the second opening 72H. The lower end of the sponge 77 is fixed to the upper surface of the support plate 78. The deposit T containing ink is removed by the sponge 77 before the ink wiper 82A2 reaches the second opening 72H. Therefore, it is possible to suppress the ink from being mixed into the pre-treatment liquid container 72.

[0090] [Wiper inclination arrangement] Next, a preferred arrangement example of the ink wiper 82 and the pretreatment liquid wiper 83 will be shown. Fig. 17 is a plan view showing the inclined arrangement of the ink wiper 82 and the pretreatment liquid wiper 83. As shown in Fig. 10, the ink wiper 82 has a wiper blade 821A (ink blade) that extends in a direction (left-right direction) intersecting the movement direction (front-back direction) during wiping. Similarly, the pretreatment liquid wiper 83 also has a wiper blade 821B (treatment liquid blade) that extends in the left-right direction.

[0091] The wiper blade 821A of the ink wiper 82 is disposed at an incline such that its left end protrudes more than its right end in the moving direction of the ink wiper 82 during wiping. Focus is placed on the ink wiper 82A1 that wipes the upstream head 4A1 of the first ink head 4A located to the right of the pre-processing head 5. As shown in FIG. 18C, the wiper blade 821A of the ink wiper 82A1 is disposed at an incline such that its left end 82L (first end) on the side where the processing liquid container 72 exists protrudes more than its right end 82R (second end) in the moving direction. The post-processing liquid wipers 84A and 84B that wipe the post-processing heads 6A and 6B are also disposed at an incline such that their left end protrudes more than their right end in the moving direction.

[0092] In contrast, the wiper blade 821B of the pretreatment liquid wiper 83 is disposed at an angle such that its right end protrudes more than its left end in the movement direction of the pretreatment liquid wiper 83. Referring also to Fig. 18B, the wiper blade 821B of the pretreatment liquid wiper 83 is disposed at an angle such that its right end 83R (third end) on the side on the right of the first opening 71H of the ink container 71 protrudes more than its opposite left end 83L (fourth end) in the movement direction.

[0093] 18A is a diagram showing a state where the head 40 is wiped by a wiper blade 8210 with no inclination. The liquid L is attached to the head 40. The wiper blade 8210 is arranged so as to extend in a direction perpendicular to the wiping direction. When wiping is performed by such a wiper blade 8210, the liquid L wiped from the head 40 drips from the left and right sides of the head 40 as shown by the arrows in the figure. For example, when the wiper blade 8210 is applied to the pretreatment liquid wiper 83, there is a risk that the pretreatment liquid dripping from the right side of the pretreatment head 5 may be mixed into the ink container 71. Furthermore, when the wiper blade 8210 is applied to the upstream head 4A1 of the first ink head 4A, there is a risk that the ink dripping from the left side of the upstream head 4A1 may be mixed into the pretreatment liquid container 72.

[0094] 18B is a diagram showing wiping of the pretreatment head 5 by the pretreatment liquid wiper 83 having an inclined wiper blade 821B. The wiper blade 821B is inclined such that the right end 83R protrudes in the wiping direction. For this reason, the pretreatment liquid L1 wiped from the pretreatment head 5 by the wiper blade 821B drips mainly from the left side of the pretreatment head 5. This reduces the possibility that the pretreatment liquid L1 drips onto the first opening 71H of the ink container 71 adjacent to the right side of the second opening 72H of the pretreatment liquid container 72.

[0095] 18C is a diagram showing the wiping state of the ink head 4 (upstream head 4A1) by the ink wiper 82 having an inclined wiper blade 821A. The wiper blade 821A is inclined such that the left end 82L protrudes in the wiping direction. Therefore, ink L2 wiped from the upstream head 4A1 by the wiper blade 821A drips mainly from the right side of the upstream head 4A1. This reduces the possibility that ink L2 will drip into the second opening 72H during wiping.

[0096] 17, 18B, and 18C, the inclined arrangement of the wiper blades 821A and 821B makes it possible to control the destinations of the pretreatment liquid L1 and the ink L2 wiped by wiping. This reduces the possibility that the pretreatment liquid L1 and the ink L2 will mix in the ink container 71 or the pretreatment liquid container 72. If the inclined arrangement of the wiper blades 821A and 821B can suppress the mixing of the pretreatment liquid L1 and the ink L2, a part or the whole of the movement range of the pretreatment liquid wiper 83 during wiping may be set directly above the first opening 71H.

[0097] Fig. 19 is a plan view showing another example of the inclination arrangement of the wipers. In Fig. 19, the ink heads 4 are provided with six ink heads 4F11, 4F12, 4F13, 4F14, 4F15, and 4F16 arranged on the front side, and six ink heads 4R11, 4R12, 4R13, 4R14, 4R15, and 4R16 arranged on the rear side. In addition, one pre-treatment head 5 is provided on the upstream side of the ink heads 4 group, and two post-treatment heads 6A and 6B are provided on the downstream side. In addition, as the container unit 70G, a container unit having an ink container 71A, a pre-treatment liquid container 72A, and a post-treatment liquid container 72B, which are partitioned from each other, is illustrated. Each partition is provided with a waste liquid discharge port 74A.

[0098] Ink wipers 82F1, 82F2, 82F3, 82F4, 82F5, and 82F6 are provided for wiping the front ink heads 4F11 to 4F16, respectively. Ink wipers 82R1, 82R2, 82R3, 82R4, 82R5, and 82R6 are also provided for wiping the rear ink heads 4R11 to 4R16, respectively. A pre-treatment liquid wiper 83 is provided for the pre-treatment head 5, and post-treatment liquid wipers 84A and 84B are provided for the post-treatment heads 6A and 6B, respectively.

[0099] The first feature of the embodiment shown in FIG. 19 is that the wipers are arranged at an inclination such that the liquids wiped by the wipers move away from each other at the boundary between the ink container 71 and the pretreatment liquid container 72A and at the boundary between the ink container 71A and the posttreatment liquid container 72B. Specifically, in the moving direction (rearward) during wiping, at the boundary between the ink container 71 and the pretreatment liquid container 72A, the pretreatment liquid wiper 83 is arranged at an inclination such that the right end protrudes more than the left end. Conversely, the ink wipers 82F1 and 82R1 that wipe the ink heads 4F11 and 4R11 are arranged at an inclination such that the left end protrudes more than the right end. This arrangement is the same as the example in FIG. 17, and makes it easier to separate and collect the pretreatment liquid and the ink. That is, the pretreatment liquid can be made to escape to the left side and reliably collected by the pretreatment liquid container 72A, and the ink can be made to escape to the right side and less likely to be mixed into the pretreatment liquid container 72A.

[0100] At the boundary between the ink container 71A and the post-treatment liquid container 72B, the post-treatment liquid wiper 84A is disposed at an incline such that its left end protrudes in the movement direction more than its right end. Conversely, the ink wipers 82F6 and 82R6 that wipe the ink heads 4F16 and 4R16 are disposed at an incline such that their right end protrudes in the movement direction more than their left end. This arrangement makes it easier to separate and recover the post-treatment liquid and the ink. That is, the post-treatment liquid is allowed to escape to the right side and be reliably recovered in the post-treatment liquid container 72B, while the ink is allowed to escape to the left side and is less likely to be mixed into the post-treatment liquid container 72B. This arrangement is effective when the post-treatment liquid reacts with the ink and causes aggregation or the like.

[0101] The second feature of the embodiment shown in FIG. 19 is that, among the ink wipers 82F1-F6 and 82R1-R6, there are pairs of adjacent wipers that are inclined in a direction in which the wiped liquid moves away from each other, and pairs that are inclined in a direction in which the wiped liquid moves toward each other. For example, in the front wiper row, the pair of ink wipers 82F2 and 82F3 and the pair of ink wipers 82F4 and 82F5 are inclined in a direction in which the wiped liquid moves away from each other. In the rear wiper row, the pair of ink wipers 82R2 and 82R3 and the pair of ink wipers 82R4 and 82R5 are inclined in a direction in which the wiped liquid moves away from each other. By adopting such an arrangement, when inks that should not be mixed with each other, for example inks that will coagulate when mixed, it is possible to separate and collect the two inks. For example, by arranging a partition plate or the like in the ink container 71A at a position corresponding to the gap between the pair of ink wipers 82F2 and 82F3, the ink wiped from the ink heads 4F12 and 4F13 can be separated and collected.

[0102] On the other hand, in the front wiper row, the pair of ink wipers 82F1 and 82F2, the pair of ink wipers 82F3 and 82F4, and the pair of ink wipers 82F5 and 82F6 are inclined in a direction in which the wiped liquid approaches each other. In the rear wiper row, the pair of ink wipers 82R1 and 82R2, the pair of ink wipers 82R3 and 82R4, and the pair of ink wipers 82R5 and 82R6 are inclined in a direction in which the wiped liquid moves away from each other. By adopting such an arrangement, it is possible to collect inks that may be mixed in a common container. Examples of inks that may be mixed include cyan and light cyan, blue and cyan, green and cyan, magenta and light magenta, etc. In this way, by using a different arrangement for a pair of ink wipers wiping an ink head that ejects ink for which color mixing is acceptable, the wiped liquids are inclined in a direction that brings them closer together, and for a pair of ink wipers for ink for which color mixing is not acceptable, the wiped liquids are inclined in a direction that moves them away from each other, ink can be recovered efficiently. [Explanation of symbols]

[0103] 1. Inkjet printer (inkjet recording device) 4 Ink head 5 Pre-treatment head (treatment liquid head) 6 Aftertreatment Head 7 Maintenance Unit 70 Container Unit 71 Ink container 71H 1st opening 72 Pretreatment liquid container (treatment liquid container) 72H 2nd opening 77 Sponge (removal part) 8 Wiping Unit 81 Wiper support plate (support plate) 812 Recess 813 Convex 82 Ink Wiper 821A Wiper Blade (Ink Blade) 821B Wiper Blade (Processing Liquid Blade) 82L, 82R Left end, right end (1st end, 2nd end) 83 Pre-processing liquid wiper (processing liquid wiper) 83R, 83L Right end, left end (3rd end, 4th end) 9 Washing unit (washing area) MW Movement Path

Claims

1. a treatment liquid head that ejects a treatment liquid; an ink head that ejects ink; a processing liquid wiper that wipes the processing liquid head; an ink wiper for wiping the ink head; an ink container having a first opening for receiving the ink; a cover member that covers an upper portion of the first opening, an inkjet recording apparatus, wherein a movement range of the treatment liquid wiper during the wiping is set to be immediately above the cover member;

2. 2. The inkjet recording apparatus according to claim 1, the cover member includes a treatment liquid container having a second opening for receiving the treatment liquid; the treatment liquid container is disposed at a position covering an upper part of the first opening, an inkjet recording apparatus, wherein a movement range of the treatment liquid wiper during the wiping is set to be immediately above the second opening;

3. 3. The inkjet recording apparatus according to claim 2, wherein the first opening and the second opening are arranged in series in a direction along a moving direction of the treatment liquid wiper during wiping, an inkjet recording apparatus, wherein the movement direction of the treatment liquid wiper is set to a direction away from the first opening;

4. 4. The inkjet recording apparatus according to claim 1, the treatment liquid wiper moves along a predetermined movement path when performing the wiping; an inkjet recording apparatus, wherein the entire movement path is set directly above the cover member;

5. In the inkjet recording apparatus according to any one of claims 1 to 3, a cleaning area for cleaning the treatment liquid wiper and the ink wiper; an inkjet recording apparatus, wherein the treatment liquid wiper is disposed at a position closer to the cleaning area than the ink wiper in a movement direction from the wiping area to the cleaning area;

6. In the inkjet recording apparatus according to any one of claims 1 to 3, a cleaning area for cleaning the treatment liquid wiper; An inkjet recording apparatus, wherein the movement direction of the treatment liquid wiper during the wiping is set to a direction in which the cleaning area is located.

7. 4. The inkjet recording apparatus according to claim 3, a cleaning area for cleaning the ink wiper; a removal unit that removes ink adhering to the ink wiper or its support member, the second opening is disposed downstream of the first opening in a movement direction of the ink wiper toward the cleaning area, The inkjet recording apparatus, wherein the removal unit is disposed upstream of the second opening.

8. In the inkjet recording apparatus according to any one of claims 1 to 3, a printing area for forming an image by ejecting ink from the ink head; an inkjet recording apparatus, wherein the treatment liquid wiper is disposed at a position closer to the printing area than the ink wiper in a movement direction from the printing area to the area where wiping is performed;

9. In the inkjet recording apparatus according to any one of claims 1 to 3, a support plate for supporting the treatment liquid wiper and the ink wiper, an inkjet recording apparatus, wherein, in a top view of the support plate, a support region of the support plate that supports the treatment liquid wiper protrudes in the movement direction during wiping more than other regions of the support plate; 10. The inkjet recording apparatus according to claim 1, wherein: a support plate for supporting the treatment liquid wiper and the ink wiper, the support plate has a shape in a top view thereof that includes a plurality of protrusions corresponding to the processing liquid wiper and the ink wiper, an ink jet recording apparatus, wherein the treatment liquid wiper and the ink wiper are disposed on the corresponding convex portions; 11. The inkjet recording apparatus according to claim 1, wherein: a support plate for supporting the treatment liquid wiper and the ink wiper, In a top view of the support plate, the support plate has a plurality of protruding plates protruding in a moving direction during wiping and recesses between the protruding plates, In an inkjet recording apparatus, the treatment liquid wiper and the ink wiper are disposed on the edge of the convex plate or the edge of the recess, respectively.

12. The inkjet recording apparatus according to claim 1, wherein: In the inkjet recording apparatus, the treatment liquid wiper and the ink wiper are different in shape or material.

13. 4. The inkjet recording apparatus according to claim 2, the ink wiper is made of an ink blade extending in a direction intersecting a moving direction during wiping, The ink blade is disposed at an angle such that a first end on the side where the treatment liquid container is present protrudes in the movement direction more than a second end on the opposite side.

14. The inkjet recording apparatus according to claim 1, wherein: the treatment liquid wiper is made of a treatment liquid blade extending in a direction intersecting a moving direction during wiping, an inkjet recording apparatus, wherein the treatment liquid blade is disposed at an angle such that a third end on the side where the ink container is present protrudes in the movement direction more than a fourth end on the opposite side.

15. The inkjet recording apparatus according to claim 1, wherein: an ink jet recording apparatus, wherein the treatment liquid head and the ink head are disposed at positions where they entirely overlap each other in the direction of movement during wiping;

16. A processing liquid head that ejects a processing liquid; an ink head that ejects ink; a processing liquid wiper that wipes the processing liquid head; an ink wiper for wiping the ink head; an ink container having a first opening for receiving the ink; an inkjet recording apparatus, wherein a movement range of the treatment liquid wiper during wiping is set above the first opening, and at a position where another member is interposed between the first opening and the treatment liquid wiper;

17. Preparing an inkjet recording device having a treatment liquid head that ejects treatment liquid, an ink head that ejects ink, a treatment liquid wiper that wipes the treatment liquid head, an ink wiper that wipes the ink head, and an ink container having a first opening that receives the ink; covering a portion above the first opening of the ink container with a cover member; setting a movement range of the processing liquid wiper to be directly above the cover member during the wiping by the processing liquid wiper.

18. Preparing an inkjet recording device having a treatment liquid head that ejects treatment liquid, an ink head that ejects ink, a treatment liquid wiper that wipes the treatment liquid head, an ink wiper that wipes the ink head, and an ink container having a first opening that receives the ink; During the wiping operation of the processing liquid wiper, the processing liquid wiper is moved to a position above the first opening where another member is interposed between the first opening and the processing liquid wiper.

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