Inkjet printer and cleaning method for a head unit

Abstract

This ink jet printer comprises: a processing liquid head for discharging a processing liquid; an ink head for discharging an ink; a first member for cleaning a nozzle placement surface of the processing liquid head; and a second member for cleaning a nozzle placement surface of the ink head, the second member differing from the first member in constituent material, cleaning method, or properties.

Description

Technical Field

[0001] The present disclosure relates to an inkjet printer having a processing liquid head that discharges a processing liquid and an ink head that discharges ink, and a method for cleaning a head unit having the processing liquid head and the ink head.

Background Art

[0002] An inkjet printer includes a head having a number of nozzles that discharge ink or a predetermined processing liquid. In such a head, it is necessary to clean the nozzle arrangement surface at a predetermined timing in order to eliminate clogging of the nozzles and remove dirt on the nozzle arrangement surface.

[0003] Patent Document 1 discloses an inkjet printer that cleans the nozzle arrangement surface of one head including a processing liquid discharge nozzle and an ink discharge nozzle with a wiping member supported by a pressing member. Patent Document 2 discloses an inkjet printer that cleans the nozzle arrangement surface of a head with different wiping members; a wiping blade of a porous member and a wiping blade of an elastic member.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Summary of the Invention

[0005] An inkjet printer according to one aspect of the present disclosure includes a processing liquid head that discharges a processing liquid, an ink head that discharges ink, a first member that cleans the nozzle arrangement surface of the processing liquid head, and a second member that cleans the nozzle arrangement surface of the ink head and is different from the first member in configuration, constituent material, cleaning method, or characteristics.

[0006] A cleaning method for a head unit according to another aspect of the present disclosure is a cleaning method for a head unit having a processing liquid head that discharges a processing liquid and an ink head that discharges ink, the method including cleaning a nozzle arrangement surface of the processing liquid head with a first member, and cleaning a nozzle arrangement surface of the ink head with a second member that is different from the first member in configuration, constituent material, cleaning method, or characteristics.

Brief Description of the Drawings

[0007]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9A

Figure 9B

Figure 10

Figure 11

Figure 12

Figure 13

Figure 14A

Figure 14B

Figure 14C

Figure 15

Figure 16

DETAILED DESCRIPTION OF THE INVENTION

[0008] Hereinafter, an embodiment of the present disclosure will be described with reference to the drawings. In this embodiment, as the inkjet printer of the present disclosure, a printer equipped with an ink head for discharging ink for image formation onto a wide and long recording medium is exemplified. The cleaning method of the head unit of the present disclosure shows an example applied to the head unit provided in the printer. The inkjet printer of this embodiment is suitable for digital textile printing in which images such as characters and patterns are printed on a recording medium (work) made of a fabric such as a woven or knitted fabric by an inkjet method. Of course, the inkjet printer and the cleaning method according to the present disclosure can also be used for applications in which various inkjet images are printed on a recording medium such as a paper sheet or a resin sheet.

[0009] [OVERALL CONFIGURATION OF INKJET PRINTER] First, the overall configuration of the inkjet printer 1 according to an embodiment of the present disclosure will be described. FIG. 1 is a front view showing the overall configuration of the inkjet printer 1 according to the embodiment, and FIG. 2 is a schematic cross-sectional view taken along line II-II of FIG. 1. In FIG. 1, FIG. 2, and the figures described later, the directions of up and down, front and back, and left and right are indicated, but these are for convenience of explanation only and do not limit the direction.

[0010] The inkjet printer 1 is a printer that prints an image on a wide and long workpiece W by an inkjet method, and includes a device frame 10, a workpiece conveyance unit 2 and a carriage 3 incorporated in the device frame 10, and a dryer 19 disposed in front of the device frame 10. Note that the description of the dryer 19 is omitted in FIG. 1. In the present 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 and the conveyance direction F of the workpiece W.

[0011] The device frame 10 forms a framework for mounting various component members of the inkjet printer 1. The workpiece conveyance unit 2 is a mechanism that intermittently feeds the workpiece W so that the workpiece W travels in the conveyance direction F from the rear to the front in a printing area where inkjet printing processing is performed. The carriage 3 mounts an ink head 4, a pre-processing head 5, a post-processing head 6, and a sub-tank (not shown), and reciprocates in the left-right direction during the inkjet printing process.

[0012] 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 component members of the inkjet printer 1 and has a left-right width corresponding to the workpiece conveyance unit 2. The right frame 112 and the left frame 113 are respectively erected adjacent to the right and left of the central frame 111. The area between the right frame 112 and the left frame 113 is a printing area 12 where printing processing is performed on the workpiece W. The printing area 12 is an area in the width direction orthogonal to the conveyance direction F of the workpiece W, that is, the area where the carriage 3 reciprocates in the main scanning direction.

[0013] The right frame 112 forms a blade wipe area 13. The blade wipe area 13 is an area for retracting the carriage 3 when the printing process is not executed, and for maintenance, it is an area where the purge process of the heads 4, 5, and 6 and the blade cleaning of the nozzle arrangement surfaces 40 (Figs. 7, 14A to 14C) of the heads 4, 5, and 6 exposed on the lower surface 3A of the carriage 3 are performed at required timings. A blade wipe device 7 (first device) for performing the blade cleaning is disposed in the blade wipe area 13. The blade wipe device 7 includes a blade wipe unit 70 having a blade BL (first member) for wiping the nozzle arrangement surface 40. Actually, the lower surface 3A of the carriage 3 and the nozzle arrangement surface 40 are wiped by the blade BL. The purge process is a process of forcibly discharging ink or a processing liquid from the nozzles of the ink head 4, the pre-processing head 5, and the post-processing head 6 for the purpose of removing bubbles in each head, etc. The blade cleaning is a process of wiping the nozzle arrangement surfaces 40 of the above-mentioned heads 4, 5, and 6 with the blade BL. The blade wipe device 7 also functions as a cap for suppressing the drying of the heads 4, 5, and 6 when they are at rest.

[0014] The left frame 113 forms a cloth wipe area 14. The cloth wipe area 14 is an area where cloth wipe cleaning is performed to clean the nozzle placement surface 40 using a cloth sheet. A cloth wipe device 8 (second device) for performing the cloth wipe cleaning is arranged in the cloth wipe area 14. The cloth wipe device 8 includes a cloth wipe unit 80 having a cloth sheet FS (second member). Note that the cloth wipe area 14 is also a turning area of the carriage 3. The carriage 3 that scans the printing area 12 from right to left in the printing process enters the cloth wipe area 14 temporarily before performing a reverse scan. During maintenance, the carriage 3 stops in the cloth wipe area 14, and cloth wipe cleaning by the cloth wipe device 8 is executed. Also, the cloth wipe device 8 is configured to be relatively small with respect to the cloth wipe area 14. Therefore, when the carriage 3 is moved to the cloth wipe area 14, the lower surface 3A (nozzle placement surface 40) of the carriage 3 can be visually observed. Therefore, the maintainability of the inkjet printer can be improved.

[0015] As described above, the inkjet printer 1 of the present embodiment includes two different wiping members, the blade BL and the cloth sheet FS, for cleaning the head. Thereby, it becomes possible to clean each nozzle placement surface according to each of different types of heads, namely, the ink head 4, the pre-treatment head 5, and the post-treatment head 6, that is, according to the characteristics of the liquid ejected from each head. Cleaning by the blade BL is applied to at least the pre-treatment head 5 and the post-treatment head 6. Cleaning by the cloth sheet FS is applied only to the ink head 4. In the present embodiment, an example is shown in which cleaning by the blade BL is applied to all the heads 4, 5, and 6. These points will be described in detail later. Hereinafter, "wiping" is exemplified as an example of "cleaning", but the mode of "cleaning" is not limited to "wiping". Note that a member with a high cleaning effect can be used for a head in which the ejection is greatly affected by the drying and sticking or thickening of the liquid. For example, when the influence on ejection is large in the order of the ink head 4, the pre-treatment head 5, and the post-treatment head 6, a member with a high cleaning effect can be used accordingly.

[0016] Further, the blade wiping device 7 is disposed in a blade wiping area 13 located on the right side (one side portion) of the printing area 12, and the cloth wiping device 8 is disposed in a cloth wiping area 14 located on the left side (the other side portion) of the printing area 12. The blade wiping area 13 and the cloth wiping area 14 are spaces that are inherently necessary for the printer 1 as a retraction space for the carriage 3 that reciprocates in the printing area 12 and a space for the turning operation. By equipping the printer 1 with the blade wiping device 7 and the cloth wiping device 8 using such spaces, it is possible to suppress an increase in the size of the printer 1 even when two different wiping members are provided.

[0017] Near the upper part of the apparatus frame 10, a single-axis robot 15 for causing the carriage 3 to reciprocate in the left-right direction, that is, the main scanning direction in the printing process, is assembled. The single-axis robot 15 is disposed above the work conveyance unit 2 so as to extend in the left-right direction. The single-axis robot 15 includes a linear motor 16 and a pair of upper and lower guide rails 17. As shown in FIG. 2, the linear motor 16 includes a stator 161 disposed in the extending direction of the single-axis robot 15 and a mover 162 that moves along the guide rail 17. The pair of guide rails 17 extends parallel to the left-right direction, and a moving block 163 on which the mover 162 is mounted is engaged. The carriage 3 is mounted on the moving block 163 and is moved leftward or rightward by the single-axis robot 15.

[0018] The work conveyance unit 2 includes a feed roller 21 that feeds out the work W before printing in the conveyance direction F, a take-up roller 22 that takes up the work W after printing, and a conveyance unit 20 disposed in the printing area 12. The feed roller 21 is a winding shaft of a feed roll WA that is a wound body of the work W before printing. The take-up roller 22 is a winding shaft of a take-up roll WB that is a wound body of the work W after the printing process. The feed roller 21 is disposed upstream of the printing area 12, and the take-up roller 22 is disposed downstream of the dryer 19.

[0019] The path between the delivery roller 21 and the take-up roller 22 and passing through the printing area 12 serves as the conveyance path for the workpiece W. Along this conveyance path, a tension roller 23, a workpiece guide 24, a conveyance roller 25, a pinch roller 26, a conveyance unit 20, a peeling roller 27, a loading roller 28, a dryer 19, and a folding roller 29 are arranged in order from the upstream side.

[0020] The tension roller 23 applies a predetermined tension to the workpiece W on the upstream side of the conveyance roller 25. The workpiece guide 24 changes the conveyance direction F of the workpiece W from upward to forward and feeds the workpiece W into the printing area 12. The conveyance roller 25 generates a conveyance force for intermittently feeding the workpiece W in the printing area 12. The pinch roller 26 forms a conveyance nip portion with the conveyance roller 25. By the pair of the conveyance roller 25 and the pinch roller 26, the workpiece W is fed out from the delivery roll WA and intermittently conveyed in the conveyance direction F so that the workpiece W passes through the printing area 12.

[0021] The conveyance unit 20 is arranged to stably convey the workpiece W in the printing area 12 without causing floating or shaking. The conveyance unit 20 includes a driving roller 201 and a driven roller 202 arranged at intervals in the front-rear direction, and a conveyance belt 203 spanned between these rollers 201, 202. The workpiece W is conveyed in the conveyance direction F while being in close contact with the surface of the conveyance belt 203. A platen 204 is arranged between the rollers 201, 202 and on the back side of the conveyance belt 203. In the printing area 12, ink and treatment liquid are respectively discharged from the ink head 4, the pre-treatment head 5, and the post-treatment head 6 onto the workpiece W.

[0022] The peeling roller 27 is disposed obliquely upward in front of the driving roller 201 and serves to peel the printed workpiece W in a state of being in close contact with the surface of the conveyor belt 203 from the surface. The workpiece W is peeled from the conveyor belt 203 at a peeling portion Bk having a predetermined peeling angle and sent to the downstream carry-in roller 28. Between the peeling roller 27 and the carry-in roller 28, the workpiece W is in a slack state. The printed workpiece W is sent from the carry-in roller 28 to the dryer 19. The dryer 19 dries the wet workpiece W by blowing warm air thereon. The folding roller 29 changes the conveyance direction F of the dried workpiece W from the forward direction to the downward direction and guides the workpiece W to the take-up roller 22.

[0023] The carriage 3 is supported in a cantilevered manner by the moving block 163 and reciprocates in the main scanning direction (left - right direction) intersecting the conveyance direction F. The carriage 3 includes a carriage frame 30 on which the above - mentioned ink head 4, pre - treatment head 5, post - treatment head 6, and a sub - tank (not shown) are mounted. 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 above - mentioned heads 4, 5, 6. The back frame 32 is a vertical plate that extends upward from the rear - end edge of the head support frame 31. The back frame 32 is fixed to the moving block 163.

[0024] [Details of the carriage] A further description will be given of the carriage 3. FIG. 3 is an enlarged perspective view of the carriage 3 shown in FIG. 1. FIG. 3 shows the conveyance direction F (sub-scanning direction) of the workpiece W and the main scanning direction S which is the moving direction of the carriage 3. In FIG. 3, an example is shown in which a plurality of ink heads 4 for discharging ink for image formation, a pre-treatment head 5 for discharging a non-coloring treatment liquid, and a post-treatment head 6 are mounted on the carriage 3. That is, the carriage 3 is a head unit having the ink head 4 and the treatment heads 5 and 6 in the present embodiment. A plurality of sub-tanks for supplying the ink and the treatment liquid to these heads 4, 5, and 6 are also mounted on the actual carriage 3. Note that the ink head 4 which is described simply in FIG. 1 is described more specifically in FIG. 3.

[0025] Each of the ink heads 4 includes a number of nozzles that discharge ink droplets by a discharge method such as a piezo method using a piezo element or a thermal method using a heating element, and an ink passage that guides ink to the nozzles. The same applies to the pre-treatment head 5 and the post-treatment head 6. As the ink, for example, an aqueous pigment ink containing an aqueous solvent, a pigment, and a binder resin can be used. The plurality of ink heads 4 in the present embodiment include first to eighth ink heads 4A to 4H that each discharge eight different colors of ink.

[0026] 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 arranged in the main scanning direction S. The ink heads 4A to 4H of each color each have two heads. For example, the first ink head 4A includes an upstream head 4A1 disposed on the upstream side in the conveyance direction F and a downstream head 4A2 disposed on the downstream side of the upstream head 4A1 and shifted to the left side in the main scanning direction S. The ink heads 4B to 4H of other colors are the same. The upstream heads of these ink heads 4B to 4H are arranged in a line in the main scanning direction S at the same position as the upstream head 4A1 in the conveyance direction F, and the downstream heads are arranged in a line in the main scanning direction S at the same position as the downstream head 4A2 in the conveyance direction F.

[0027] The pretreatment head 5 and the post-treatment head 6 are arranged at positions different from those of the ink head 4 in the conveyance direction F. The pretreatment head 5 is arranged upstream of the ink head 4 in the conveyance direction F. FIG. 3 shows an example in which one pretreatment head 5 is arranged near the left end of the array of the ink heads 4. The pretreatment head 5 is adjacent to the left of the upstream head 4A1 of the first ink head 4A and is arranged side by side in the main scanning direction S at the same position as the downstream head 4A2. On the other hand, the post-treatment head 6 is arranged downstream of the ink head 4 in the conveyance direction F. FIG. 3 shows an example in which one post-treatment head 6 is arranged near the right end of the array of the ink heads 4. The post-treatment head 6 is adjacent to the right of the downstream head 4H2 of the eighth ink head 4H and is arranged side by side in the main scanning direction S at the same position as the upstream head 4H1.

[0028] The pretreatment head 5 discharges a pretreatment liquid for performing a predetermined pretreatment on the workpiece W. The pretreatment liquid is discharged from the pretreatment head 5 to a position on the workpiece W where ink has not yet been discharged from the ink head 4. The pretreatment liquid is a non-color-developing treatment liquid that does not develop color even when it adheres to the workpiece W, and is, for example, a treatment liquid that exhibits functions such as enhancing the fixing property of ink to the workpiece W and the aggregating property of ink pigments. As such a pretreatment liquid, a treatment liquid in which a cationic resin that is positively charged in a solvent is blended can be used.

[0029] The post-treatment head 6 discharges a post-treatment liquid for performing a predetermined post-treatment on the workpiece W to which ink has adhered. The post-treatment liquid is discharged from the post-treatment head 6 to a position on the workpiece W after ink has been discharged from the ink head 4. The post-treatment liquid is also a non-color-developing 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 fixing property and fastness of the ink image printed on the workpiece W by the ink head 4, for example, the resistance to rubbing and scratching. As such a post-treatment liquid, for example, a silicone-based treatment liquid can be used. Thus, since the discharge target of the post-treatment head 6 is different from that of the pretreatment head 5, different members may be used as members for cleaning the nozzle arrangement surfaces 40 of both.

[0030] An opening 31H is provided at the location where the head of the head support frame 31 is disposed. The ink heads 4A to 4F, the pre-treatment head 5, and the post-treatment head 6 are assembled to the head support frame 31 so as to be fitted into their respective openings 31H. From each opening 31H, a nozzle arrangement surface 40 disposed on the lower end surface of each of the heads 4, 5, 6 is exposed.

[0031] As described above, the inkjet printer 1 according to the present embodiment is an all-in-one type printer in which three types of heads, namely, the ink head 4, the pre-treatment head 5, and the post-treatment head 6, are mounted on a single carriage 3. According to this printer 1, for example, in the printing step of performing inkjet printing on a fabric in digital resist printing, the step of discharging the pre-treatment liquid and the step of discharging the post-treatment liquid can be integrally executed. Therefore, the resist process can be simplified and the resist apparatus can be made compact.

[0032] [Maintenance of Heads] As described above, the inkjet printer 1 includes a blade wiping device 7 that cleans the nozzle arrangement surface 40 (see FIG. 7) using a blade BL and a cloth wiping device 8 that cleans the nozzle arrangement surface 40 using a cloth sheet FS for the maintenance of the heads 4, 5, 6. The nozzle arrangement surface 40 is a surface on which a large number of nozzle openings for discharging ink or treatment liquid are arranged in a predetermined pattern in each of the heads 4, 5, 6, and is exposed on the lower surface 3A of the carriage 3. The difference between the ink, the pre-treatment liquid, and the post-treatment liquid exemplified above is the presence or absence of a binder resin. That is, the ink must include a pigment contained according to the developing color and a binder resin that serves to bind the pigment. On the other hand, the pre-treatment liquid and the post-treatment liquid do not contain a pigment, and a binder resin is not essential. Due to the presence or absence of the pigment and the binder resin, the physical properties of the liquid are different between the ink and the pre-treatment liquid and the post-treatment liquid. In consideration of this difference in physical properties, the blade wiping device 7 and the cloth wiping device 8 are appropriately used separately to clean the heads 4, 5, 6.

[0033] The blade cleaning using the blade wiping device 7 is periodically performed based on the printing time, printing area, number of operating days, etc. At the time of blade cleaning, the carriage 3 is moved to the blade wiping area 13 by the operation of the uniaxial robot 15. Before blade cleaning, a purge is performed to forcibly discharge ink or treatment liquid from the ink head 4, the pretreatment head 5, and the post-treatment head 6. After the purge, a non-contact wipe (first cleaning) is performed by the blade BL of the blade wiping device 7 to wipe the droplets hanging on the nozzle arrangement surface 40 of the heads 4, 5, 6, and a contact wipe (second cleaning) is performed by bringing the cleaning blade into contact with the nozzle arrangement surface 40 and wiping it. In this embodiment, the second wiping is different from the first wiping in terms of whether it can contact the part to be wiped. This contact / non-contact wipe will be described in detail based on FIGS. 14A to 14C.

[0034] The cloth wipe cleaning using the cloth wiping device 8 is performed only on the ink head 4 after the above blade cleaning. That is, for the pretreatment head 5 and the post-treatment head 6, only the blade BL is used for wiping, but for the ink head 4, a two-stage wiping is performed, in which wiping with the blade BL is followed by wiping with the cloth sheet FS. This is because, since the ink head 4 discharges a liquid (ink) containing a pigment and a binder resin, blade cleaning alone may not be sufficient to clean the nozzle arrangement surface. At the nozzles of the ink head 4, it is important to form a predetermined meniscus at the nozzle opening for accurate ink jetting and dot formation. Even if nozzle clogging occurs and the above purge and blade cleaning are performed, it is difficult to form the desired meniscus at the nozzle opening. By wiping the nozzle arrangement surface with the cloth sheet FS after blade cleaning, it becomes possible to form an appropriate meniscus at the nozzle opening. On the other hand, if wiping with the cloth sheet FS is immediately performed after the purge, the cloth sheet FS will absorb the droplets excessively and the cleaning function will be impaired immediately, so wiping with the blade BL is performed first.

[0035] Since the pretreatment head 5 and the post-treatment head 6 are heads that discharge a liquid not containing a pigment and a binder resin, cloth wiping cleaning may be omitted. Note that there may be a case where only cloth wiping cleaning is performed on the ink head 4 without performing the above purge (to be described later based on FIG. 15). During cloth wiping cleaning, as shown in FIG. 4, the carriage 3 is moved to the cloth wiping area 14.

[0036] In the above, the blade BL is exemplified as the first member for cleaning both the ink head 4 and the processing heads 5 and 6, and the cloth sheet FS is exemplified as the second member for cleaning only the ink head 4. The role of the first member is exclusively to roughly wipe off the liquid present on the nozzle arrangement surface 40 of the heads 4, 5, and 6 after purging. On the other hand, the role of the second member is to wipe off the liquid remaining on the nozzle arrangement surface 40 and the nozzle openings after the previous wiping. Note that the cleaning by the first member and the second member may be performed while supplying a liquid to the nozzle arrangement surface 40. Water or the like can be used as the liquid, and the liquid may be supplied to the nozzle arrangement surface 40 by spraying from a predetermined supply port or oozing from a permeable component.

[0037] In view of the above-mentioned roles, as the first member, a non-liquid-absorbing wiper or a solid wiper having no voids or the like can be used. The blade BL is an example thereof. Like a wiper for wiping raindrops on a car window, it is sufficient if the first member can push away the droplets present on the nozzle arrangement surface 40. For this reason, liquid absorbency for sucking up droplets is not necessarily required in the first member, and a spatula-shaped solid member is sufficient. Generally, a water-repellent film is coated on the nozzle arrangement surface 40 of the heads 4, 5, and 6. In order not to damage this water-repellent film as much as possible, it is desirable to use a non-liquid-absorbing solid member formed of a rubber material or a resin material having a predetermined rigidity rather than a metal material as the first member.

[0038] On the other hand, as the second member, a liquid-absorbent wiper or a porous wiper may be used. If it is a liquid-absorbent and porous wiper, it can absorb liquid droplets remaining on the nozzle arrangement surface 40 and excess liquid droplets at the nozzle openings. The cloth sheet FS is an example thereof. As the cloth sheet FS, for example, a woven fabric woven from ultra-fine fibers can be used. A foam, sponge, or sponge body with a small bubble diameter can also be used as the second member. Among these, it is desirable to use the cloth sheet FS that has low sliding resistance with respect to the lower surface 3A of the carriage 3 and is excellent in liquid absorption. Thus, in the present embodiment, the first wiping member and the second member differ in the constituent materials or their configurations.

[0039] [Details of the Blade Wiper Device] Subsequently, a specific example of the blade wiper device 7 will be described with reference to FIGS. 4 to 7. FIG. 4 is a perspective view of a specific example of the blade wiper device 7 shown in FIG. 1. The blade wiper device 7 includes a container unit 50 and a blade wiper unit 70. The upper diagram in FIG. 5 is a plan view of the blade wiper unit 70, and the lower diagram in FIG. 5 is a plan view showing the arrangement of the heads 4, 5, and 6 mounted on the carriage 3. FIG. 6 is a perspective view of the ink blade 72 provided in the blade wiper unit 70. The ink blade 72 corresponds to the blade BL (the first wiping member) shown in FIG. 1. FIG. 7 is a schematic cross-sectional view of the carriage 3 and the blade wiper unit 70.

[0040] As described above, during blade cleaning, the purge operation of the heads 4, 5, and 6 is performed first. The container unit 50 is a container for collecting the ink, pretreatment liquid, and post-treatment liquid discharged from the heads 4, 5, and 6 during the purge operation. The blade wiper unit 70 is a unit that performs blade cleaning of the nozzle arrangement surface 40.

[0041] The container unit 50 is structured to separately collect the pretreatment liquid, the ink, and the post-treatment liquid. As the pretreatment liquid, a treatment liquid that enhances the fixability of the ink and the aggregability of the ink pigment is used. Therefore, when the pretreatment liquid and the ink are mixed, the mixture may aggregate, which may impede recovery into the waste liquid tank. On the other hand, even when the post-treatment liquid is mixed with the ink, no aggregation or the like occurs. This is the reason for the above-mentioned separate recovery in the container unit 50.

[0042] The container unit 50 includes an ink container 51 and a pretreatment liquid container 52 disposed on the front side of the frame structure 500, and a cleaning liquid tray 53 disposed on the rear side of the frame structure 500. The frame structure 500 includes a pair of left and right side frames 501 extending in the front-rear direction, and a front frame 502 connecting the front ends of these side frames 501. A handle 503 for pulling out the container unit 50 is attached to the front frame 502. A plurality of waste liquid hoses 504 are drawn out from below the front frame 502. In addition, the frame structure 500 is equipped with a slider 505 that enables the container unit 50 to be pulled out, and a chain protector 506 that houses electric cables and hoses.

[0043] The ink container 51 is a container that collects the ink and the post-treatment liquid discharged from the ink head 4 and the post-treatment head 6, respectively, in the purge operation, and is provided with a first opening 51H on its upper surface for receiving the ink and the post-treatment liquid. The ink container 51 includes a rectangular bottom surface 511 that is long in the left-right direction, four tapered surfaces 512 that extend upward from the four edges of the bottom surface 511, and an upper end flange 508 formed on the periphery of the first opening 51H. The ink container 51 also collects the ink and the post-treatment liquid wiped from the nozzle arrangement surfaces 40 (FIG. 7) of the ink head 4 and the post-treatment head 6 exposed on the lower surface 3A of the carriage 3 during the blade cleaning.

[0044] The pretreatment liquid container 52 is disposed at a position covering a part above the first opening 51H. The pretreatment liquid container 52 is a container that collects the pretreatment liquid discharged from the pretreatment head 5 in the purge operation, and is provided with a second opening 72H on its upper surface for receiving the pretreatment liquid. The pretreatment liquid container 52 also collects the pretreatment liquid wiped from the nozzle arrangement surface 40 of the pretreatment head 5 in the blade cleaning. The cleaning liquid tray 53 is a container that collects the cleaning liquid CL (FIG. 7) for cleaning the blade wiping unit 70 contaminated by the execution of the blade cleaning.

[0045] The container unit 50 is provided with an overflow passage 541, a processing liquid passage 542, and a relay passage 543 for the flow of the collected liquid. The overflow passage 541 has a start-end opening at the bottom surface 511 of the ink container 51, and the end side is a passage leading to a waste liquid container (not shown). The processing liquid passage 542 has a start-end opening near the bottom surface of the pretreatment liquid container 52, and the end side is a passage leading to the waste liquid container. The relay passage 543 has a start-end opening at the bottom surface of the cleaning liquid tray 53 and an end-opening near the bottom surface 511 of the ink container 51.

[0046] A cap rubber 55 is attached to the upper surface 50A of the container unit 50. The cap rubber 55 is disposed so as to surround the periphery of the first opening 51H of the ink container 51. The carriage 3 is movable in the vertical direction as shown by the arrow A1 in FIG. 7. When the carriage 3 is in the standby mode in the blade wipe area 13 or when the printer 1 is in a standby state, etc., the carriage 3 is lowered, and the lower surface 3A of the head support frame 31 comes into contact with the cap rubber 55. Thereby, the nozzle arrangement surfaces 40 of the heads 4, 5, and 6 are sealed.

[0047] Above the cleaning liquid tray 53, a cleaning unit 56 for injecting the cleaning liquid CL of the blade wipe unit 70 is arranged. The cleaning unit 56 includes a nozzle holding plate 561 and a plurality of cleaning nozzles 562 held by the nozzle holding plate 561. The cleaning nozzles 562 radiate the cleaning liquid CL in a fan-shaped spray pattern onto each of the blades 72, 73, 74 of the blade wipe unit 70 described below. The cleaning liquid CL is supplied to the cleaning nozzles 562 from a cleaning liquid tank (not shown) via a cleaning liquid hose 563.

[0048] The blade wipe unit 70 includes a blade support plate 71 and a group of blades supported by the blade support plate 71; an ink blade 72, a pretreatment liquid blade 73, and a post-treatment liquid blade 74. The blade wipe unit 70 is movable in the front-rear direction as shown by the arrow A2 in FIG. 7. The blade support plate 71 is a flat plate-like member and moves in the front-rear direction between the carriage 3, the cleaning unit 56, and the container unit 50. The ink blade 72 moves backward while being in contact with the nozzle arrangement surface 40 of the ink head 4 exposed on the lower surface 3A, thereby wiping the nozzle arrangement surface 40. Similarly, the pretreatment liquid blade 73 and the post-treatment liquid blade 74 wipe the nozzle arrangement surfaces 40 of the pretreatment head 5 and the post-treatment head 6, respectively. That is, the blade wipe unit 70 can simultaneously wipe the nozzle arrangement surfaces 40 of all the heads 4, 5, 6 by a single backward movement operation.

[0049] The structure of the blade wipe unit 70 will be further described in detail. The upper diagram in FIG. 5 shows a plan view of the blade support plate 71 holding the blades 72, 73, 74. The lower diagram in FIG. 5 shows the arrangement of the heads 4, 5, 6 mounted on the carriage 3 and the correspondence with the blades 72, 73, 74. The arrangement mode of the heads 4, 5, 6 shown in the lower diagram of FIG. 5 is the same as the mode exemplified in FIG. 3 above.

[0050] The blade support plate 71 is provided with a plurality of strip-shaped convex plates 711. The plurality of convex plates 711 protrude in the rear direction which is the moving direction during wiping. Between adjacent convex plates 711, recesses 712 that are recessed on the front side are formed. At the edge (rear end) of the convex plate 711 and the edge of the recess 712, an ink blade 72 for wiping the nozzle arrangement surface 40 of the ink head 4 is attached. The ink blade 72 arranged at the edge of the convex plate 711 is for wiping the upstream heads of the ink heads 4 of various colors, such as the ink blade 72A1 arranged for the upstream head 4A1 of the first ink head 4A. On the other hand, the ink blade 72 arranged at the edge of the recess 712 is for wiping the downstream heads of the ink heads 4 of various colors, such as the ink blade 72A2 arranged for the downstream head 4A2.

[0051] The pretreatment liquid blade 73 for wiping the nozzle arrangement surface 40 of the pretreatment head 5 is attached to the edge (rear end) of a convex piece 714 that protrudes rearward more than other regions of the blade support plate 71. The convex piece 714 extends further rearward from the rear end of the leftmost convex plate 711. A window portion 715 corresponding to the recess 712 is provided on the front side of the convex piece 714. Thus, by arranging the pretreatment liquid blade 73 at the position that protrudes most in the moving direction on the blade support plate 71, it becomes difficult for the pretreatment liquid wiped by the pretreatment liquid blade 73 to adhere to other parts of the blade support plate 71.

[0052] The post-treatment liquid blade 74 for wiping the nozzle arrangement surface 40 of the post-treatment head 6 is attached near the front of the right end of the blade support plate 71. The post-treatment head 6 is arranged in parallel with the upstream head 4H1 of the eighth ink head 4H on the upstream side and the downstream side in the conveyance direction F. Corresponding to such a head arrangement, the blade support plate 71 is provided with a holding piece 716 and a window portion 717 near its right end. The holding piece 716 supports an ink blade 72H1 that wipes the upstream head 4H1 at its rear end edge. An ink blade 72H2 for wiping the downstream head 4H2 is supported at the edge of a recess 712 adjacent to the left side of the holding piece 716. The window portion 717 is an opening arranged in front of the holding piece 716. The post-treatment liquid blade 74 is supported at the opening edge on the front side of the window portion 717.

[0053] The blade support plate 71 has a plurality of convex portions 713 arranged corresponding to each of the above-described blades 72, 73, and 74. The convex portions 713 are continuously provided at the rear end of the convex plate 711, the base end edge of the recess 712, the rear end of the convex piece 714, and the base end edge of the window portion 717, respectively. These convex portions 713 are small protrusions that protrude in the moving direction during wiping in terms of the shape in a top view. The blades 72, 73, and 74 are arranged on the corresponding convex portions 713. By adopting such an arrangement, it is possible to make it difficult for the ink and treatment liquid adhering to the blades 72, 73, and 74 to adhere to the blade support plate 71.

[0054] FIG. 6 shows the detailed structure of the ink blade 72 corresponding to the blade BL (first member) in FIG. 1. The pretreatment liquid blade 73 and the post-treatment liquid blade 74 also have the same structure. The ink blade 72 includes a blade body 721, a first holder 722, and a second holder 723. The blade body 721 is a spatula-shaped plate material that actually contacts the nozzle arrangement surface 40 to perform a wiping operation. The upper end of the blade body 721 is at a position protruding upward from the upper surface of the blade support plate 71.

[0055] The first holder 722 and the second holder 723 are members that sandwich and hold the blade body 721. The first holder 722 is fitted into a recess provided in the convex portion 713 and fixed by screwing, and supports the lower part of the back surface of the blade body 721. The second holder 723 is attached to the lower part of the front surface of the blade body 721. The second holder 723 is provided with a pair of openings 724, and the blade body 721 is also provided with through holes at the same positions as the openings 724. On the other hand, the first holder 722 is provided with a pair of claw portions 725. The claw portions 725 are inserted through the through holes and the openings 724, and lock the second holder 723 at the peripheral edge of the openings 724. Due to this locking force, the blade body 721 is sandwiched between the first holder 722 and the second holder 723.

[0056] [Details of the cloth wiping device] Subsequently, a specific example of the cloth wiping device 8 will be described with reference to FIGS. 8 to 11. FIG. 8 is a perspective view of the cloth wiping device 8, showing the situation of cloth wiping and cleaning. The cloth wiping device 8 includes a moving unit 60 and a cloth wiping unit 80. FIG. 9A is a left side view of the cloth wiping device 8, and FIG. 9B is a side view of the moving unit 60. FIG. 10 is a perspective view of the cloth wiping unit 80, and FIG. 11 is a view showing the state where the cloth wiping unit 80 is in the cleaning posture.

[0057] The cloth wiping unit 80 includes a cloth sheet roll FSR which is a bundle of cloth sheets for cloth wiping. The moving unit 60 moves the cloth wiping unit 80 in the front-rear direction. In cloth wiping and cleaning, a wiping area 8W formed by the cloth sheet FS fed out from the cloth sheet roll FSR is pressed against the nozzle arrangement surface 40 of the ink head 4 exposed on the lower surface 3A of the carriage 3. FIG. 8 shows this pressing state, and when the moving unit 60 moves the cloth wiping unit 80 backward from this state, the nozzle arrangement surface 40 is wiped by the cloth sheet FS in the wiping area 8W.

[0058] The cloth wiper unit 80 is a unit that actually performs cloth wiper cleaning. The moving unit 60 moves the cloth wiper unit 80 between a cleaning position for cleaning the lower surface 3A (nozzle arrangement surface 40) and a retracted position where the cleaning is not performed. The cloth wiper unit 80 shown in Fig. 9A is in a state of being moved to the retracted position, and the cloth wiper unit 80 shown in Fig. 11 is in a state of being moved to the cleaning position. The moving unit 60 includes a moving plate 61, a linear guide 62, a ball screw 63, a nut 64, a cloth wiper moving motor 65, and an attitude change guide 66.

[0059] The moving plate 61 is a flat plate that is substantially rectangular in side view and is movable in the front-rear direction along the linear guide 62. The cloth wiper unit 80 is mounted on the moving plate 61. Near the corner portion at the rear end and upper end of the moving plate 61, a rotating pin 81P that protrudes leftward is attached. The rotating pin 81P is a pin that serves as the rotation axis of the cloth wiper unit 80. The cloth wiper unit 80 is mounted on the moving plate 61 so as to be rotatable about the axis of the rotating pin 81P.

[0060] The linear guide 62 includes a guide base 620, a guide rail 621, and a block 622. The guide base 620 is a flat plate member that serves as a mounting base for the guide rail 621, the ball screw 63, the cloth wiper moving motor 65, and the attitude change guide 66. In Fig. 9A, the description of the guide base 620 is omitted. The guide rail 621 is a rail that extends linearly in the front-rear direction. The block 622 is fitted into the guide rail 621 and is movable in the front-rear direction along the guide rail 621. The moving plate 61 is fixed to the block 622.

[0061] The ball screw 63 is pivotally supported by the guide base 620 so as to extend in the front-rear direction parallel to the guide rail 621. The nut 64 is screwed onto the ball screw 63 and is attached to the moving plate 61. The cloth wiper moving motor 65 is arranged such that the motor shaft is connected to the rear end of the ball screw 63, and drives the ball screw 63 to rotate forward or backward about its axis. Due to the rotation of the ball screw 63, the nut 64 moves in the front-rear direction, and accordingly, the moving plate 61 moves in the front-rear direction while being guided by the guide rail 621.

[0062] The posture change guide 66 is a member against which the contact portion 812 of the cloth wiper unit 80 abuts when the moving plate 61 moves. The rotation posture of the rotation pin 81P of the cloth wiper unit 80 about its axis is changed according to the contact position of the contact portion 812 against the posture change guide 66. The posture change guide 66 includes a first horizontal portion 661, a second horizontal portion 662, and an inclined portion 663. The first horizontal portion 661 extends horizontally in the extending direction of the linear guide 62 at a position of a predetermined height. The second horizontal portion 662 is at a position that is a predetermined height higher than the first horizontal portion 661 and is horizontally separated rearward from the first horizontal portion 661, and extends horizontally in the front-rear direction. The inclined portion 663 is a portion connecting between the first horizontal portion 661 and the second horizontal portion 662 having a height difference.

[0063] The cloth wiper unit 80 includes a base plate 81, a pay-out portion 82, a take-up portion 83, a pressing roller 84, a conveying roller 85, and a transmission belt 86. The base plate 81 is a substantially square flat plate in side view having a size larger than that of the moving plate 61. A bearing bush 811 projects from the right surface of the base plate 81 near the corner portion at the rear end and the upper end. The bearing bush 811 has a rotary shaft hole 81A through which the rotary pin 81P of the moving plate 61 is inserted. The base plate 81 is rotatable with respect to the moving plate 61 with the bearing bush 811 pivotally supported by the rotary pin 81P as a pivot point.

[0064] On the left surface of the base plate 81, near the corner at the front end and the lower end, a contact portion 812 protrudes. The contact portion 812 is, for example, a roller rotatable about an axis extending in the left-right direction. The corner portion where the contact portion 812 is disposed is diagonally located with respect to the corner portion where the bearing bush 811 is disposed. The contact portion 812 contacts the posture change guide 66. FIG. 9A shows a state where the contact portion 812 contacts the first horizontal portion 661 of the posture change guide 66, and the base plate 81 takes a horizontal posture. FIG. 11 shows a state where the contact portion 812 contacts the second horizontal portion 662 which is higher than the first horizontal portion 661, and the base plate 81 rotates about the axis of the rotation pin 81P, and the front side is lifted up.

[0065] A feeding portion 82 and a take-up portion 83 are assembled to the base plate 81. The feeding portion 82 feeds out a cloth sheet FS for performing cloth wipe cleaning. The feeding portion 82 includes a pay-out roller 821 that holds a cloth sheet roll FSR which is a wound body of an unused cloth sheet FS. A torque limiter 82L is attached to the rotating shaft of the pay-out roller 821. The take-up portion 83 takes in the cloth sheet FS after being used in the cloth wipe cleaning. The take-up portion 83 includes a take-up roller 831 around which the used cloth sheet FS is wound. A torque limiter 83L is also attached to the rotating shaft of the take-up roller 831.

[0066] A wipe area 8W using the cloth sheet FS is provided between the feeding portion 82 and the take-up portion 83. The wipe area 8W is an area where a cloth sheet portion that is pressed against the lower surface 3A of the carriage 3 and actually performs cloth wipe cleaning of the nozzle arrangement surface 40 is located among the long cloth sheet FS formed as the cloth sheet roll FSR. An unused cloth sheet FS is sequentially fed out from the cloth sheet roll FSR of the feeding portion 82 to the wipe area 8W. The cloth sheet FS used for cloth wipe cleaning in the wipe area 8W is sequentially taken in by the take-up portion 83.

[0067] The pressing roller 84 is composed of an elastic roller and supports the cloth sheet FS in the wiping area 8W. The pressing roller 84 serves to press the cloth sheet FS in the wiping area 8W against the lower surface 3A. The pressing roller 84 is pivotally supported near the upper side of the base plate 81 such that a part of the pressing roller 84 protrudes upward from the upper side of the base plate 81. By supporting the cloth sheet FS with such a pressing roller 84 from below, the cloth sheet FS in the wiping area 8W also protrudes upward from the upper side of the base plate 81.

[0068] A one-way clutch (not shown in the figure) is attached to the rotating shaft of the pressing roller 84. The one-way clutch causes the pressing roller 84 to rotate only in the feeding direction of the cloth sheet FS. A pair of pulleys 842 are mounted on both ends of the rotating shaft of the pressing roller 84. While the pressing roller 84 is an elastically deformable roller, the pulleys 842 are formed of a hard material that does not substantially elastically deform. By pressing the pair of pulleys 842 against the lower surface 3A, the positional relationship between the pressing roller 84 and the nozzle arrangement surface 40 is determined. Therefore, the amount of pressing of the cloth sheet FS against the nozzle arrangement surface 40 by the pressing roller 84 can be made constant and uniform in the axial direction.

[0069] In the feeding direction of the cloth sheet FS, a first guide roller 843 is disposed upstream of the pressing roller 84, and a second guide roller 844 is disposed downstream of the pressing roller 84. Downstream of the second guide roller 844, a conveying roller 85 and a tension roller 845 are sequentially arranged. The conveying roller 85 feeds the cloth sheet FS from the feeding section 82 through the wiping area 8W toward the take-up section 83. A one-way clutch 851 is incorporated in the rotating shaft of the conveying roller 85. The tension roller 845 applies tension to the cloth sheet FS wound up at the take-up section 83.

[0070] A gear (not shown) is attached to the shaft end of the conveying roller 85. When the base plate 81 rotates with respect to the moving plate 61 with the bearing bush 811 as the rotation fulcrum, a driving force is applied to the gear, causing the conveying roller 85 to rotate. The cloth sheet FS is fed out downstream by the amount of rotation of the conveying roller 85. Further, due to the rotation of the conveying roller 85, the used cloth sheet FS is taken up by the take-up portion 83. As shown in FIG. 10, a transmission belt 86 is stretched between the conveying roller 85 and the take-up roller 831. When the conveying roller 85 rotates by a certain amount in response to the posture change of the cloth wiping unit 80, the rotation is transmitted to the take-up roller 831 by the transmission belt 86. As a result, the take-up roller 831 takes up the cloth sheet FS by the amount of rotation of the conveying roller 85.

[0071] A spray unit 87 is disposed between the first guide roller 843 and the pressing roller 84. The spray unit 87 has a spray gun 871 that blows out a cleaning liquid composed of pure water or a liquid containing a cleaning component. The spray unit 87 is attached to the left side plate of the apparatus frame 10. The spray gun 871 sprays the cleaning liquid onto the cloth sheet FS in the wiping area 8W upstream of the pressing roller 84. By wetting the cloth sheet FS with the cleaning liquid immediately before the cloth wiping and cleaning, the cleaning effect of the nozzle arrangement surface 40 can be enhanced.

[0072] FIG. 9A shows the retracted posture in which the cloth wiping unit 80 does not clean the nozzle arrangement surface 40, and FIG. 11 shows the cleaning posture in which the nozzle arrangement surface 40 is cleaned. When the cloth wiper moving motor 65 is driven and the moving plate 61 is moved rearward from the state of FIG. 9A, the cloth wiping unit 80 also moves rearward. The contact portion 812 that was in contact with the first horizontal portion 661 (FIG. 9B) of the posture change guide 66 comes into contact with the inclined portion 663. As the contact portion 812 climbs up the inclined portion 663, the base plate 81 rotates with the bearing bush 811 inserted through the rotation pin 81P as the rotation fulcrum, and the front end portion is lifted.

[0073] FIG. 11 shows a state where the contact portion 812 has climbed over the inclined portion 663 and reached the second horizontal portion 662. The contact portion 812 is lifted by the height difference between the first horizontal portion 661 and the second horizontal portion 662, and the base plate 81 rotates about the axis of the rotation pin 81P by a rotation angle corresponding to the lifted amount. Due to this rotation, the wipe area 8W is also lifted, and the cloth sheet FS at the portion supported by the pressing roller 84 is in contact with the lower surface 3A (nozzle arrangement surface 40). That is, the cloth sheet FS in the wipe area 8W enables the cloth wipe cleaning of the lower surface 3A.

[0074] By driving the cloth wiper moving motor 65, the moving plate 61 is further moved rearward, so that the nozzle arrangement surface 40 is cleaned by the cloth sheet FS in the wipe area 8W. In the present embodiment, as shown in FIG. 3, the ink heads 4 of each color are arranged in two rows in the front-rear direction. Also, the width of the cloth sheet FS has a width that can cover two ink heads 4 arranged in the main scanning direction S. Therefore, it is desirable to move at least the wipe area 8W by a stroke corresponding to two rows in the front-rear direction. For this reason, the front-rear length of the second horizontal portion 662 of the posture changing guide 66 is set to be longer than the stroke.

[0075] When the wipe area 8W is moved to the rear end side and the cloth wipe cleaning is completed, the carriage 3 is lifted slightly, and the wipe area 8W is separated from the lower surface 3A. Thereafter, by driving the cloth wiper moving motor 65, the moving plate 61 is returned forward. Eventually, the contact position of the contact portion 812 changes from the second horizontal portion 6622 to the inclined portion 663, and then from the inclined portion 663 to the first horizontal portion 661. As a result, the base plate 81 rotates about the axis of the rotation pin 81P, and the cloth wipe unit 80 returns to a horizontal state, that is, a retracted posture. After that, the carriage 3 is moved by two heads in the main scanning direction S, and the cloth wipe cleaning for the next ink head 4 is repeated in the above-described procedure.

[0076] [Control Configuration] FIG. 12 is a block diagram showing a part of the control configuration of the printer 1. The printer 1 includes a controller 33, a carriage drive motor 34 whose operation is controlled by the controller 33, a carriage lifting motor 35, a head drive unit 36, a work transfer motor 37, a work winding motor 38, a blade drive unit 75, and the above-described cloth wiper movement motor 65.

[0077] The carriage drive motor 34 generates a driving force to move the carriage 3 in the left - right direction between the blade wipe area 13 and the cloth wipe area 14 through the printing area 12. The carriage drive motor 34 corresponds to the linear motor 16 shown in FIG. 1. The carriage lifting motor 35 generates a driving force to move the carriage 3 in the up - down direction in the blade wipe area 13 and the cloth wipe area 14. The head drive unit 36 executes the ejection operations of ink, pretreatment liquid, and post - treatment liquid from each of the heads 4, 5, 6. The work transfer motor 37 is a motor that serves as a drive source for transferring the work W in the transfer direction F in the printer 1. In the example of FIG. 2, drive motors such as the transfer roller 25 and the drive roller 201 of the transfer unit 20 correspond to the work transfer motor 37. The work winding motor 38 is a motor that serves as a drive source for rotating the winding roller 22 that winds up the work W after printing.

[0078] The blade drive unit 75 operates the blade wipe device 7 under the control of the controller 33 to perform maintenance including purge processing of the heads 4, 5, 6 and blade cleaning. Specifically, as purge processing, the blade drive unit 75 causes high - pressure ink, pretreatment liquid, and post - treatment liquid to be ejected from the heads 4, 5, 6 respectively to clean the nozzles. Also, as blade cleaning, the blades 72, 73, 74 of the blade wipe unit 70 are moved in a state of being close (in the case of non - contact wiping described later) or in contact with the nozzle arrangement surface 40 of the heads 4, 5, 6.

[0079] The cloth wiper movement motor 65 moves the moving plate 61 on which the cloth wipe unit 80 is mounted under the control of the controller 33, and performs cloth wipe cleaning of the ink head 4. The controller 33 sets a cleaning sequence of the nozzle arrangement surface 40 by the cloth wipe unit 80, and controls the cloth wiper movement motor 65, the carriage drive motor 34, etc. based on the cleaning sequence.

[0080] The controller 33 consists of a processor that operates according to a program, etc., and comprehensively controls the operations of each part of the printer 1. Regarding the cleaning control of the heads 4, 5, and 6, the controller 33 controls the blade wipe device 7 (first device) and the cloth wipe device 8 (second device) to perform the required blade cleaning and cloth wipe cleaning.

[0081] For the ink head 4, the controller 33 performs two-stage wiping (two-stage cleaning) in which the nozzle arrangement surface 40 is wiped by both the blade wipe device 7 and the cloth wipe device 8. The wiping order is first to wipe the nozzle arrangement surface 40 with the blade wipe device 7, and then to wipe the nozzle arrangement surface 40 with the cloth wipe device 8. Also, as the wiping of the ink head 4 by the blade wipe device 7, the controller 33 sequentially executes a first wiping (first cleaning) in which the ink blade 72 does not contact the nozzle arrangement surface 40 and a second wiping (second cleaning) in which the ink blade 72 contacts the nozzle arrangement surface 40. On the other hand, for the pre-treatment head 5 and the post-treatment head 6, the controller 33 wipes the nozzle arrangement surface 40 only with the blade wipe device 7. Note that before the blade cleaning by the blade wipe device 7, the controller 33 executes a purge that forcibly discharges ink and processing liquid from the heads 4, 5, and 6 respectively.

[0082] [Specific Example of Head Cleaning Control] A specific example of the cleaning control by the controller 33 described above will be described with reference to the flowcharts shown in FIGS. 13 and 15. FIG. 13 is a flowchart showing an example of the cleaning operation of the heads 4, 5, and 6 in the printer 1. The controller 33 determines whether the current time is the cleaning timing (step S1). Whether it is the cleaning timing is determined with reference to the cumulative printing time, printing area, number of operating days, etc. since the previous head cleaning. Note that not only the regular elements listed above, but also irregular elements such as when high-density printing is continuously performed or when a non-ejecting head is detected may be considered to determine whether it is the cleaning timing. When it is not the cleaning timing (NO in step S1), the controller 33 sets the blade wiping device 7 and the cloth wiping device 8 to the standby state.

[0083] When it is the cleaning timing (YES in step S1), it is determined whether the carriage 3 is present in the blade wiping area 13 (step S2). When the carriage 3 is not present in the blade wiping area 13 (NO in step S2), the controller 33 controls the carriage drive motor 34 to move the carriage 3 to the blade wiping area 13 (step S3).

[0084] When the carriage 3 is present in the blade wiping area 13 (YES in step S2), the controller 33 causes the blade cleaning to be executed. The controller 33 controls the blade drive unit 75 to first execute a purge that forcibly ejects ink and the processing liquid from the heads 4, 5, and 6 respectively (step S4). The roles of the purge include discharging the bubbles held in each nozzle of the heads 4, 5, and 6, and blowing away the solids adhering to the nozzle arrangement surface 40 with the purge flow. For the ink head 4, it also includes softening the ink-derived solids with the ink purge flow to make them easier to peel off.

[0085] The purge volume can be set in the range of about 3 ml to 60 ml per head. Note that purging may be performed only on the ink head 4. Further, when nozzle clogging has occurred only in a specific ink head 4, purging may be performed only on that specific head. In this case, in order to prevent adverse effects (damage to the water-repellent film) on the head due to dry wiping, it is desirable to discharge a small amount (about 0.2 ml to 1.0 ml) of ink or processing liquid from the heads other than the specific ink head 4.

[0086] Next, the controller 33 causes the blade wiping unit 70 to perform non-contact wiping (first cleaning) of the heads 4, 5, and 6 (step S5). In non-contact wiping, a gap of about 0.2 mm to 0.8 mm is provided between the blade body 721 of the ink blade 72 and the nozzle arrangement surface 40 of the ink head 4 to perform a wiping operation. The same applies to the pre-treatment head 5 and the post-treatment head 6. The controller 33 controls the carriage lifting motor 35 to lower the carriage 3 so that the gap is formed. By this non-contact wiping, after purging, the droplets hanging on the nozzle arrangement surfaces 40 of the heads 4, 5, and 6 are wiped off. The moving speed of the blade wiping unit 70 in non-contact wiping can be selected from the range of about 10 mm / s to 100 mm / s.

[0087] Subsequently, the controller 33 causes the blade wiping unit 70 to perform contact wiping (second cleaning) of the heads 4, 5, and 6 (step S6). In contact wiping, the blade body 721 of the ink blade 72 is pressed against the nozzle arrangement surface 40 of the ink head 4 to perform a wiping operation. The same applies to the pre-treatment head 5 and the post-treatment head 6. The pressing force (linear pressure) of the pressing can be set to about 0.1 N / m to 10 N / m. The controller 33 lowers the carriage 3 so that the pressing force is achieved. The moving speed of the blade wiping unit 70 in contact wiping can also be selected from the range of about 10 mm / s to 100 mm / s.

[0088] Figures 14A to 14C are diagrams schematically showing the cleaning procedures of the above steps S4 to S6. Here, one ink head 4 and one ink blade 72 for wiping the head 4 are shown. Figure 14A shows the purge operation of step S4. Purge liquid PA, that is, ink, is being ejected from the nozzle arrangement surface 40 of the ink head 4.

[0089] Figure 14B is a diagram showing the execution status of the non-contact wipe in step S5. There is the above-mentioned gap between the ink blade 72 (blade main body 721) and the nozzle arrangement surface 40. The blade support plate 71 on which the ink blade 72 is mounted is relatively moved with respect to the carriage frame 30. The droplets DR adhering to the nozzle arrangement surface 40 are wiped by the ink blade 72.

[0090] Figure 14C is a diagram showing the execution status of the contact wipe in step S6. The ink blade 72 is in contact with the nozzle arrangement surface 40 and is in a deformed state by the pressing force. In this state, the blade support plate 71 is relatively moved with respect to the carriage frame 30. Thereby, the nozzle arrangement surface 40 itself is wiped by the ink blade 72. In this way, the nozzle arrangement surface 40 is cleaned by two-stage wiping of non-contact and contact. Since the ink blade 72 and the nozzle arrangement surface 40 do not come into contact during non-contact wiping, the water-repellent film coated on the nozzle arrangement surface 40 is not affected. If all of the removal of the droplets DR depends on the contact wipe of the blade, the water-repellent film is likely to be damaged. By preceding the non-contact wipe for wiping the droplets DR as in this embodiment, while enhancing the cleaning property of the nozzle arrangement surface 40, damage to the water-repellent film can be suppressed.

[0091] Returning to FIG. 13, after finishing the blade cleaning in steps S4 to S6, the controller 33 drives the carriage lifting motor 35 to raise the carriage 3 so that the nozzle arrangement surface 40 is separated from the ink blade 72. Subsequently, the controller 33 controls the carriage drive motor 34 to move the carriage 3 to the cloth wiping area 14 (step S7). After the movement, the controller 33 lowers the carriage 3 so that the nozzle arrangement surface 40 is at a predetermined height position. Subsequently, the controller 33 drives the cloth wiper movement motor 65 to cause the cloth wiping unit 80 to perform cloth wiping cleaning of the nozzle arrangement surface 40 of the ink head 4 (step S8).

[0092] That is, the moving plate 61 of the moving unit 60 is relatively moved with respect to the carriage frame 30, and the nozzle arrangement surface 40 is wiped with the cloth sheet FS. Before this wiping, the cleaning liquid is sprayed from the spray unit 87 onto the cloth sheet FS. It is desirable to mix a surfactant that reduces the surface tension in the cleaning liquid for protecting the water-repellent film on the nozzle arrangement surface 40. The pressing force of the cloth sheet FS against the nozzle arrangement surface 40 by the pressing roller 84 is 0.02 N / mm 2 ~0.20 N / mm 2 and more preferably, it can be set in the range of 0.05 N / mm 2 ~0.15 N / mm 2 The relative movement speed of the cloth sheet FS can be selected from the range of about 10 mm / s to 100 mm / s.

[0093] The control shown in FIG. 13 is a so-called "full wipe operation" that is performed in the order of purging of the heads 4, 5, 6, non-contact / contact wiping of the heads 4, 5, 6 by the blades 72, 73, 74, and wiping of the ink head 4 by the cloth sheet FS. It is not always necessary to perform this full wipe operation, and the full wipe operation may be executed only when required.

[0094] FIG. 15 is a flowchart showing a control example for selectively executing a full wipe operation. The controller 33 checks whether the current mode of the printer 1 is the "normal mode" (step S11). The "normal mode" is a state in which no accidents such as the occurrence of non-ejecting nozzles or continuous high-density printing have occurred. In the "normal mode", it is assumed that only the cloth wipe cleaning of the ink head 4 is periodically performed.

[0095] If it is in the "normal mode" (YES in step S11), the controller 33 determines whether the current time is the cleaning timing (step S12). If it is the cleaning timing (YES in step S12), the controller 33 moves the carriage 3 to the cloth wipe area 14 and operates the cloth wipe device 8 to wipe the ink head 4 with the cloth sheet FS (step S13). If it is not the cleaning timing (NO in step S12), the controller 33 sets the blade wipe device 7 and the cloth wipe device 8 to the standby state.

[0096] On the other hand, if it is not in the "normal mode" (NO in step S11), the controller 33 operates the blade wipe device 7 and the cloth wipe device 8 in a timely manner to execute the "full wipe operation" as illustrated in FIG. 13 (step S14). Note that when a non-ejecting nozzle occurs in the ink head 4, a sequence may be set in which the cloth wipe device 8 first performs cloth wipe cleaning on the ink head 4, and if the non-ejection does not recover, the "full wipe operation" is executed.

[0097] [Modification Embodiment of Printer] In the printer 1 shown in FIG. 1, an example is shown in which the blade wipe device 7 is arranged in the blade wipe area 13 located on the right side of the printing area 12, and the cloth wipe device 8 is arranged in the cloth wipe area 14 located on the left side. Instead of this arrangement, a layout in which both the blade wipe device 7 and the cloth wipe device 8 are arranged on one side portion of the printing area 12 may be used.

[0098] FIG. 16 is a front view showing the overall configuration of an inkjet printer 1A according to a modified embodiment. On the right side of the printing area 12, a right frame 112A that partitions a maintenance area 13A is arranged. In the maintenance area 13A, a blade wiping device 7 and a cloth wiping device 8 are accommodated. That is, in the printer 1A, both blade cleaning and cloth wiping can be performed in the maintenance area 13A.

[0099] In the layout of the printer 1 in FIG. 1, the left and right areas of the printing area 12 required for the reciprocating movement of the carriage 3 are utilized as a blade wiping area 13 and a cloth wiping area 14, respectively, so there is an advantage in reducing the size of the printer 1. However, after blade cleaning in the blade wiping area 13, it is necessary to move the carriage 3 to the cloth wiping area 14 and then perform cloth wiping. On the other hand, according to the printer 1A of the modified embodiment, in the maintenance area 13A, both blade cleaning and cloth wiping can be performed by simply moving the carriage 3 slightly. Therefore, it is possible to shorten the maintenance time. Also, accessories required for head cleaning, such as supply pipes for cleaning liquid, waste liquid pipes, and tanks, can be concentrated near the maintenance area 13A, and there is an advantage in simplifying and streamlining the arrangement of the accessories.

[0100] In addition, the printer of the present disclosure can take various modified embodiments. In the above embodiment, an example is shown in which the constituent materials of the members are different, such as the first member being the blade BL and the second member being the cloth sheet FS, and the cleaning mode is wiping. The meaning of the first member and the second member being "different" is polysemous and is not limited to different constituent materials. For example, (1) the configurations of the first member and the second member are different, (2) the cleaning methods of the first member and the second member are different, (3) the characteristics of the first member and the second member are different, etc. can be exemplified.

[0101] Examples of the above (1) include (a) the first member and the second member having different shapes, (b) different positional relationships with respect to the nozzle arrangement surface, (c) different numbers of arrangements, and the like. Specific examples of the above (a) include aspects such as making the shapes of the surfaces of the first member and the second member facing the nozzle arrangement surface (for example, one being a smooth surface and the other being a rough surface), the contact area, and the contact surface width different from each other. Specific examples of the above (b) include aspects such as the first member being positioned in the main scanning direction with respect to the nozzle arrangement surface and the second member being positioned in the sub-scanning direction, or vice versa, or making the inclination angles with respect to the nozzle arrangement surface different. Specific examples of the above (c) include aspects such as arranging a plurality of first members in one processing liquid head while arranging one second member in one ink head.

[0102] Examples of the above (2) include (d) different cleaning modes for the first member and the second member, (e) different cleaning directions, (f) different cleaning pressures or cleaning speeds, (g) different numbers of cleaning times, etc. As specific examples of the above (d), examples can be given of adopting different cleaning modes for the first member and the second member from among cleaning modes such as wiping the nozzle arrangement surface, applying a fluid such as compressed air, an inert gas, or a liquid to the nozzle arrangement surface, and transferring, adsorbing, or sucking the dirt on the nozzle arrangement surface. For example, water or the like can be used as the liquid, and supplying the liquid to the nozzle arrangement surface can be achieved by spraying it from a predetermined supply port or allowing it to ooze out from a permeable component. As specific examples of the above (e), for example, examples can be given of setting the moving directions of the first member and the second member when wiping the nozzle arrangement surface to different moving directions from among options such as the main scanning direction, the sub-scanning direction, the diagonal direction, and the nozzle arrangement direction. The above (f) examples include modes in which the pressures at which the first member and the second member are pressed against the nozzle arrangement surface are made different from each other, modes in which they are in contact or non-contact with respect to the nozzle arrangement surface, and modes in which the cleaning speed of either one is made faster than the other. As the above (g), an example is a mode in which the number of times the first member and the second member clean the nozzle arrangement surface is made different from each other. For example, for the processing liquid head, an example can be given of a mode in which the first member performs reciprocating cleaning (cleaning twice), and for the ink head, the second member performs cleaning only on the forward or return path (cleaning once).

[0103] Examples of the above (3) include making the liquid absorption property, water repellency, strength such as rigidity and hardness, elastic modulus, electrical characteristics such as conductivity and capacitance different between the first member and the second member, etc. It is not limited to the mode in which the first member and the second member are made of different materials and the above characteristics are different, but it may also be a mode in which both are made of the same or similar materials but the above characteristics are different.

[0104] Then, by appropriately combining the above (1) to (3), "different" first and second members may be realized.

[0105] Alternatively, instead of the above-described embodiments, members having the above-mentioned "different" configurations, constituent materials, cleaning methods, or characteristics may be employed for each color of the ink head or for each processing liquid of the processing liquid head. For example, the configuration, constituent materials, cleaning method, or characteristics may be made different between the black ink head 4 and the color ink heads 4 other than black, or between the pretreatment head 5 and the post-treatment head 6. In this case, the members for cleaning the nozzle arrangement surface of the black ink head 4 and the members for cleaning the nozzle arrangement surface of the color ink heads 4 other than black may be made different. Also, the members for cleaning the nozzle arrangement surface of the pretreatment head 5 and the members for cleaning the nozzle arrangement surface of the post-treatment head 6 may be made different. Needless to say, at that time, the above (1) to (3) may be appropriately combined to realize "different" members.

[0106] Also, in the above-described embodiment, an example in which wiping is performed on the ink head 4 with the blade BL and the cloth sheet FS has been shown. Instead of performing wiping a plurality of times with the same wiping member, when performing wiping a plurality of times using "different" wiping members, various combinations of wiping members can be adopted.

[0107] The combination of the first member and the second member may be appropriately selected. That is, when the first member is a blade, the second member is a cloth sheet; when the first member is a non-absorbent wiper, the second member is an absorbent wiper; or when the first member is a solid wiper, the second member is not limited to a combination with a porous wiper. For example, when the second member is a cloth sheet, an absorbent wiper, or a solid wiper, as the first member, an appropriate one among the configurations, constituent materials, cleaning methods, and characteristics exemplified in the above (1) to (3) can be adopted as a combination.

Explanation of Reference Numerals

[0108] 1 Inkjet printer 12 Printing area 13 Blade wipe area (one side part) 14 Cloth wipe area (the other side part) 3 Carriage (Head Unit) 33 Controller 4 Ink Head 40 Nozzle Arrangement Surface 5 Pretreatment Head (Processing Liquid Head) 6 Post-treatment Head (Processing Liquid Head) 7 Blade Wiper Device (First Device) 70 Blade Wiper Unit 72 Ink Blade (Blade) 73 Pretreatment Liquid Blade (Blade) 74 Post-treatment Liquid Blade (Blade) 8 Cloth Wiper Device (Second Device) 80 Cloth Wiper Unit BL Blade FS Cloth Sheet W Workpiece (Recording Medium)

Claims

1. A processing liquid head that discharges a processing liquid, An ink head that discharges ink, A first member that cleans the nozzle arrangement surfaces of the processing liquid head and the ink head, An inkjet printer comprising: a second member that is different from the first member in terms of constituent material or cleaning method and that cleans the nozzle arrangement surface of the ink head.

2. The inkjet printer according to claim 1, wherein the first member is a blade and the second member is a cloth sheet.

3. A processing liquid head that discharges a processing liquid, An ink head that discharges ink, A first member comprising a non-absorbent wiper that cleans the nozzle arrangement surfaces of the processing liquid head and the ink head, An inkjet printer comprising: a second member comprising an absorbent wiper that cleans the nozzle arrangement surface of the ink head.

4. A processing liquid head that discharges a processing liquid, An ink head that discharges ink, A first member comprising a solid wiper that cleans the nozzle arrangement surfaces of the processing liquid head and the ink head, An inkjet printer comprising: a second member comprising a porous wiper that cleans the nozzle arrangement surface of the ink head.

5. A processing liquid head that discharges a processing liquid, An ink head that discharges ink, A first member that cleans the nozzle arrangement surface of the processing liquid head, In an inkjet printer comprising: a second member that is different from the first member in terms of constituent material or cleaning method and that cleans the nozzle arrangement surface of the ink head, A first device having the first member, A second device having the second member, A controller that controls the first device and the second device, and the controller executes control to clean the nozzle arrangement surface of the ink head with the first device and the second device, and to clean the nozzle arrangement surface of the processing liquid head with only the first device.

6. The inkjet printer according to claim 5, wherein the controller executes control to clean the nozzle arrangement surface of the ink head with the first device and then with the second device.

7. The inkjet printer according to claim 6, The controller further controls the ink ejection operation of the ink head, and after executing a purge for forcibly ejecting ink from the ink head, sequentially executes cleaning in the first device and cleaning in the second device, an inkjet printer.

8. In the inkjet printer according to any one of claims 1 to 4, a carriage on which the processing liquid head and the ink head are mounted; a conveyance area of a recording medium to be inkjet printed, a printing area in which the carriage reciprocates in a width direction orthogonal to the conveyance direction of the recording medium for inkjet printing processing; a first device having the first member; a second device having the second member, and the first device is disposed on one side portion of the printing area, and the second device is disposed on the other side portion of the printing area, an inkjet printer.

9. In the inkjet printer according to any one of claims 1 to 4, a carriage on which the processing liquid head and the ink head are mounted; a conveyance area of a recording medium to be inkjet printed, a printing area in which the carriage reciprocates in a width direction orthogonal to the conveyance direction of the recording medium for inkjet printing processing; a first device having the first member; a second device having the second member, and both the first device and the second device are disposed on one side portion of the printing area, an inkjet printer.

10. In the inkjet printer according to any one of claims 1 to 4, the processing liquid head includes a pre-processing head that ejects a processing liquid before ejection of the ink, and a post-processing head that ejects a processing liquid after ejection of the ink, the first member for the pre-processing head and the first member for the post-processing head are made to have different configurations, constituent materials, cleaning methods or characteristics, an inkjet printer.

11. In the inkjet printer according to any one of claims 1 to 4, the ink head includes a black ink head that ejects black ink, and a color ink head that ejects ink other than black, the second member for the black ink head and the second member for the color ink head are made to have different configurations, constituent materials, cleaning methods or characteristics, an inkjet printer.

12. In the inkjet printer according to Claim 1, an inkjet printer in which the cleaning method of the second member is different from the cleaning method of the first member in at least one of the cleaning mode, cleaning direction, number of cleaning times, cleaning pressure, or cleaning speed.

13. A cleaning method for a head unit having a processing liquid head that discharges a processing liquid and an ink head that discharges ink, wherein a nozzle arrangement surface of the processing liquid head and the ink head is cleaned with a first member, and a cleaning method for a head unit, wherein the nozzle arrangement surface of the ink head is cleaned with a second member different from the first member in terms of constituent material or cleaning method.

14. In the cleaning method for a head unit according to Claim 13, a cleaning method for a head unit, wherein a blade is used as the first member and a cloth sheet is used as the second member.

15. A cleaning method for a head unit having a processing liquid head that discharges a processing liquid and an ink head that discharges ink, wherein a nozzle arrangement surface of the processing liquid head is cleaned with a first member, and in the cleaning method for a head unit, wherein the nozzle arrangement surface of the ink head is cleaned with a second member different from the first member in terms of constituent material or cleaning method, the nozzle arrangement surface of the processing liquid head is cleaned only with the first member, and the nozzle arrangement surface of the ink head is subjected to a two-step cleaning, which is first cleaned with the first member and then cleaned with the second member.

16. In the cleaning method for a head unit according to Claim 15, the cleaning of the ink head by the first member includes a first cleaning in which the first member does not contact the nozzle arrangement surface and a second cleaning in which the first member contacts the nozzle arrangement surface, a cleaning method for a head unit.

17. In the cleaning method for a head unit according to Claim 15, the cleaning of the ink head by the first member includes a first cleaning in which the first member does not contact the nozzle arrangement surface, and a second cleaning in which the first member contacts the nozzle arrangement surface, which is performed after the first cleaning, and after the second cleaning, cleaning is performed using a cloth sheet as the second member. A cleaning method for a head unit.

18. In the cleaning method for a head unit according to Claim 17, a purge for forcibly discharging ink from the ink head is executed before the first cleaning, a cleaning method for a head unit.

Images