CN107443909B

CN107443909B - Cleaning device for liquid ejecting head and liquid ejecting apparatus

Info

Publication number: CN107443909B
Application number: CN201710240991.4A
Authority: CN
Inventors: 绿川雄
Original assignee: SII Printek Inc
Current assignee: SII Printek Inc
Priority date: 2016-04-14
Filing date: 2017-04-13
Publication date: 2020-06-16
Anticipated expiration: 2037-04-13
Also published as: JP2017193163A; JP2017193159A; CN107443909A

Abstract

Provided are a cleaning device for a liquid ejecting head and a liquid ejecting apparatus, wherein the cleaning operation is simplified, the amount of ink used in the cleaning operation is suppressed, and the drying of the ink is suppressed. The inkjet head is provided with a cover unit (66), wherein the cover unit (66) can move along the Z direction to cover the ejection surface of the inkjet head (5), and the cover unit (66) can move between the following positions: an opening position for opening the nozzle holes, a carriage cap position for covering the nozzle holes in a state of being close to the ejection surface in the Z direction, and a head cap position for closing the nozzle holes in a state of being in contact with the ejection surface in the Z direction.

Description

Cleaning device for liquid ejecting head and liquid ejecting apparatus

Technical Field

The present invention relates to a cleaning device for a liquid ejecting head and a liquid ejecting apparatus.

Background

The inkjet printer includes an inkjet head that reciprocates in a main scanning direction, and a conveying mechanism that conveys a recording medium (e.g., paper) in a sub-scanning direction orthogonal to the main scanning direction. The inkjet head discharges ink in a droplet form through the nozzle holes while reciprocating in the main scanning direction. When the ink hits the recording medium, various kinds of information are recorded on the recording medium.

In addition, in the inkjet printer, a cleaning device that cleans a surface of the inkjet head on which the nozzle holes open (hereinafter, referred to as a discharge surface) is mounted in order to maintain and recover discharge performance of the nozzle holes. For example, a cleaning device described in patent document 1 includes a capping device (catching) that contacts a projection surface and discharges ink through a nozzle hole.

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open No. 2004-90240.

Disclosure of Invention

Problems to be solved by the invention

In an ink jet printer, it is preferable to frequently cover the nozzle hole in a case other than the printing operation in order to suppress drying of ink. That is, if the ink dries and the viscosity of the ink increases, the discharge amount, discharge speed, and the like of the ink discharged from the nozzle holes change, and there is a risk that desired printing characteristics cannot be obtained.

However, the inkjet printer described in patent document 1 has a problem that the amount of ink used increases and the scale of the cleaning operation increases because ink is discharged through the nozzle holes every time cleaning is performed.

The invention provides a cleaning device for a liquid ejecting head and a liquid ejecting apparatus, which not only simplifies cleaning operation and restrains ink usage amount during the cleaning operation, but also can restrain ink drying.

Means for solving the problems

In order to solve the above-described problems, a cleaning device for a liquid ejecting head according to an aspect of the present invention includes a cap unit (cap unit) that is movable in a direction normal to an ejection surface of an ejection orifice opening in the liquid ejecting head to cap the ejection surface, the cap unit being configured to be movable between: an opening position for opening the ejection hole, a first cover position for covering the ejection hole in a state of being close to the ejection surface in the normal direction, and a second cover position for closing the ejection hole in a state of being in contact with the ejection surface in the normal direction.

According to this aspect, since the cover unit is configured to be movable to both the first cover position and the second cover position, an optimum cover state can be selected according to the standby state and the cleaning content of the liquid ejecting apparatus. For example, the first cap may be selected when the standby time is short, and the second cap may be selected when the standby time is long and the recovery of the discharge performance is aimed. As a result, not only the cleaning operation is simplified and the amount of liquid used in the cleaning operation is suppressed, but also the drying of the liquid can be suppressed, for example, as compared with a case where the liquid is discharged through the ejection holes every time the cleaning operation is performed.

In the above aspect, the liquid ejecting head may further include a detection unit that detects a relative position of the cap unit and the liquid ejecting head in the normal direction.

According to this aspect, by detecting the relative positions of the cap unit and the liquid ejecting head in the normal direction, the liquid ejecting head can be reliably capped at the first cap position and the second cap position. That is, even if the position in the normal direction of the liquid ejecting head is changed after shipment according to the type (material, thickness, etc.) of the recording medium, the detection position (reference position) by the detection member can be kept constant. Therefore, by setting the first cap position and the second cap position to distances from the reference position, the liquid ejecting head can be reliably capped regardless of the position in the normal direction of the liquid ejecting head. As a result, drying of the liquid can be reliably suppressed.

In the above aspect, the cap unit may further include an elastically deformable seal member that surrounds the liquid ejecting head at the first cap position and the second cap position.

According to this aspect, for example, unlike the case where the seal member and the liquid ejecting head face each other in the normal direction, the seal member can be prevented from being sandwiched between the cap unit and the liquid ejecting head in the normal direction in the process of moving the cap unit to the first cap position and the second cap position. This prevents the movement of the cover unit from being restricted by the seal member during the movement from the first cover position to the second cover position. As a result, the space between the liquid ejecting head and the cap unit can be sealed at each cap position, and the drying of the liquid can be reliably suppressed.

Further, when the seal member is in contact with the outer peripheral surface of the liquid ejecting head, the seal member slides on the outer peripheral surface of the liquid ejecting head when the cap unit and the carriage are moved relative to each other in the normal direction. Therefore, even if liquid or the like solidifies between the seal member and the liquid ejecting head, the seal member and the liquid ejecting head are easily detached.

In the above aspect, the plurality of liquid ejecting heads may be mounted on a carriage, and the sealing member may surround the carriage at the first cap position and the second cap position to surround the plurality of liquid ejecting heads together.

According to this aspect, compared to a configuration in which each liquid ejecting head is individually surrounded, fluctuations in air pressure during attachment and detachment of the cap are small. Therefore, the meniscus formed at the ejection orifice can be suppressed from being broken.

In the above aspect, the cap unit may further include a cap housing mechanism that comes into contact with the ejection surface of the liquid ejecting head at the second cap position and that is impregnated with the cleaning liquid.

According to this aspect, by contacting the ejection surface of the liquid ejecting head at the second cap position of the cap unit, the ejection surface can be cleaned by the cleaning liquid impregnated in the second cap member. This can remove the liquid and the like adhering to the ejection surface, and can improve the ejection performance.

In the above aspect, the cap unit may further include an engagement portion that engages in a main scanning direction of the liquid ejecting head among tangential directions of the ejection surface, and the cap unit may be movable in the normal direction in accordance with movement of the liquid ejecting head in the main scanning direction in a state where the liquid ejecting head is engaged with the engagement portion.

According to this aspect, the cap unit can be moved to the open position, the first cap position, and the second cap position in conjunction with movement of the liquid ejecting head in the main scanning direction.

Thus, the configuration can be simplified and the cost can be reduced as compared with a case where the liquid ejecting head and the cap unit are moved by separate driving mechanisms.

In the above aspect, the liquid ejecting apparatus may further include a blade unit that is arranged in the cap unit in a sub-scanning direction intersecting a main scanning direction of the liquid ejecting head among tangential directions of the ejection surface to wipe the ejection surface, and the blade unit and the cap unit may be integrally movable in the sub-scanning direction.

According to this aspect, the ejection surface of the liquid ejecting head can be wiped off by the blade unit while the blade unit and the cap unit are moving in the sub-scanning direction. In particular, the liquid ejecting apparatus can be downsized in the main scanning direction as compared with a configuration in which the squeegee unit and the cap unit are arranged in line in the main scanning direction. In this case, even if the blade unit is provided corresponding to the plurality of liquid ejecting heads arranged in the main scanning direction, the liquid ejecting apparatus can be prevented from being increased in size. Therefore, a small liquid ejecting apparatus with a short cleaning time can be provided.

In the above aspect, the squeegee unit may be movable between: a wiping position capable of abutting on the ejection surface in the normal direction, and a spacing position spaced from the ejection surface in the normal direction.

According to this aspect, since the squeegee mechanism is movable between the wiping position and the spaced position, when the squeegee unit is returned to the position before wiping after wiping of the ejection surface, interference between the liquid ejecting head and the squeegee unit can be suppressed. This can prevent the liquid adhering to the blade unit during the wiping operation from adhering to the liquid ejecting head again during the recovery.

A liquid ejecting apparatus according to an aspect of the present invention includes a liquid ejecting head and a cleaning device according to the above aspect.

According to this aspect, since the cleaning device of the above aspect is provided, the liquid ejecting apparatus can be provided which suppresses drying of the liquid, has excellent printing characteristics, and has high reliability.

A liquid ejecting apparatus according to an aspect of the present invention includes: in the cleaning device according to the above aspect, the liquid ejecting head includes an ejection hole for ejecting the liquid, and the carriage is mounted with the plurality of liquid ejecting heads, and the carriage is configured to be movable relative to the cleaning device to an opposing position opposing the cleaning device in a normal direction of an ejection surface of the liquid ejecting head where the ejection hole is open, and a chamfered edge is formed on an outer peripheral edge of an end portion of the carriage that is located on the cleaning device side in the normal direction at the opposing position.

According to this aspect, when the end portion of the carriage on the cleaning device side passes through the cover unit from the open position to the first cover position and the second cover position, the sealing member can be prevented from contacting the corner portion of the carriage. This makes it possible to smoothly move the seal member to the first cover position and the second cover position, and to improve the durability of the seal member.

Effects of the invention

According to one embodiment of the present invention, the cleaning operation is simplified, the amount of ink used in the cleaning operation is reduced, and drying of the ink can be reduced.

Drawings

Fig. 1 is a schematic configuration diagram of a printer according to a first embodiment;

fig. 2 is a perspective view of an ink jet head according to a first embodiment;

fig. 3 is an exploded perspective view of the ink jet head according to the first embodiment;

fig. 4 is a perspective view of the cleaning device according to the first embodiment;

fig. 5 is a side view of the cleaning unit according to the first embodiment as viewed from one side in the X direction;

fig. 6 is a perspective view of a carriage cover according to the first embodiment;

fig. 7 is a schematic configuration diagram of the inkjet head, the carriage, and the cover unit viewed from the X direction showing a state where the cover unit is at an open position;

fig. 8 is a schematic configuration diagram of the ink jet head, the carriage, and the cover unit viewed from the X direction showing a state where the cover unit is at the carriage cover position;

fig. 9 is a schematic configuration diagram of the ink jet head, the carriage, and the cover unit viewed from the X direction showing a state where the cover unit is at the head cap position;

FIG. 10 is a perspective view of a headgear mechanism according to a first embodiment;

FIG. 11 is a cross-sectional view of the squeegee unit corresponding to line XI-XI of FIG. 4;

fig. 12 is a schematic configuration diagram of a cleaning liquid supply mechanism according to the first embodiment;

FIG. 13 is a movement explanatory diagram for explaining the wiping method;

FIG. 14 is a movement explanatory diagram for explaining the wiping method;

FIG. 15 is a movement explanatory diagram for explaining the wiping method;

fig. 16 is an operation explanatory diagram for explaining a carriage cover method;

FIG. 17 is an operation explanatory diagram for explaining a hood method;

fig. 18 is a flowchart for explaining a printing standby method;

fig. 19 is a schematic perspective view of a printer according to a second embodiment;

fig. 20 is a perspective view of a cleaning region in the printer according to the second embodiment;

fig. 21 is a side view of the cleaning unit according to the second embodiment as viewed from one side in the X direction;

FIG. 22 is a sectional view corresponding to line XXII-XXII in FIG. 20;

fig. 23 is a cross-sectional view corresponding to fig. 22 showing a state where the carriage cover is at the carriage cover position;

fig. 24 is an operation explanatory diagram for explaining a carriage cover method;

FIG. 25 is an operation explanatory diagram for explaining a hood method;

fig. 26 is a schematic configuration diagram of a printer for explaining a modification of the unit guide;

fig. 27 is a schematic configuration diagram of a printer for explaining a modification of the unit guide;

fig. 28 is a schematic configuration diagram of a printer for explaining a modification of the unit guide;

fig. 29 is a schematic configuration diagram of a printer for explaining a modification of the unit guide;

fig. 30 is a perspective view showing a modified example of the squeegee mechanism.

Detailed Description

Embodiments according to the present invention will be described below with reference to the drawings. In the following description, an ink jet printer (hereinafter, simply referred to as a printer) that records on a recording medium with ink will be described as an example of a liquid ejecting apparatus including a liquid ejecting head cleaning apparatus according to an embodiment of the present invention. In the drawings used in the following description, the scale of each member is appropriately changed so that each member can be recognized.

(first embodiment)

[ Printer ]

Fig. 1 is a schematic configuration diagram of a printer 1 in the present embodiment.

As shown in fig. 1, the printer 1 is a large printer 1 used for industrial use, for example. The printer 1 includes a conveyance mechanism 2, an ink supply mechanism 3, a scanning mechanism 4, an inkjet head 5, and a cleaning device 6. Further, reference numeral 7 denotes a housing constituting the external appearance of the printer 1. The frame 7 accommodates the above-described components.

In the following description, a rectangular coordinate system of X, Y, Z will be used as necessary. In this case, the X direction coincides with a conveyance direction (sub-scanning direction) of the recording medium P (e.g., paper). The Y direction coincides with the scanning direction (main scanning direction) of the inkjet heads 5. The Z direction (normal direction) represents a height direction orthogonal to the X direction and the Y direction.

The transport mechanism 2 transports the recording medium P in the X direction. Specifically, the conveying mechanism 2 includes a grid roller (grid roller)11 extending in the Y direction, a pinch roller (pinch roller)12 extending parallel to the grid roller 11, and a driving mechanism (not shown) such as a motor for rotating the grid roller 11 around the shaft.

The ink supply mechanism 3 includes an ink tank 13, an ink pipe 14 connecting the ink tank 13 and the inkjet head 5, and a supply pump (not shown) for supplying the ink in the ink tank 13 to the inkjet head 5.

The plurality of ink tanks 13 are arranged in the Y direction. Each ink tank 13 contains a plurality of (four in the present embodiment) inks of different colors, such as yellow, magenta, cyan, and black, for example. The types of ink are not limited to four types, and can be changed as appropriate.

The ink pipe 14 is, for example, a flexible hose having flexibility. The ink pipes 14 connect the ink tanks 13 and the ink jet heads 5, respectively.

The supply pump pressurizes the inside of the ink pipe 14 to send ink to the inkjet head 5 through the ink pipe 14.

The scanning mechanism 4 reciprocally scans the inkjet head 5 in the Y direction. Specifically, the scanning mechanism 4 includes a carriage 21 on which the inkjet head 5 is mounted, and a drive mechanism 22 that moves the carriage 21 in the Y direction.

The drive mechanism 22 includes a pair of pulleys 24 (only one pulley 24 is shown in fig. 1) arranged at intervals in the Y direction, an endless belt 25 wound between the pair of pulleys 24, and a drive motor 26 for driving and rotating the one pulley 24.

The carriage 21 is configured to be movable on a guide rail, not shown, extending in the Y direction. A plurality of inkjet heads 5 are mounted on the carriage 21. In the illustrated example, a plurality of (four in the present embodiment) ink jet heads 5 that discharge inks of different colors such as yellow, magenta, cyan, and black are mounted on the carriage 21.

< ink jet head >

Next, the inkjet head 5 will be described. Fig. 2 is a perspective view of the ink-jet head 5. Fig. 3 is an exploded perspective view of the ink-jet head 5. Each ink jet head 5 is formed of the same configuration except for the color of the ink to be supplied. Therefore, in the following description, one ink jet head 5 will be described as an example, and the description of the other ink jet heads 5 will be omitted.

As shown in fig. 2 and 3, the inkjet head 5 is a two-line type inkjet head 5 in which two lines of ink are formed by a plurality of nozzle holes 31 and 32 for discharging ink.

The inkjet head 5 mainly includes a first head chip 33, a second head chip 34, a nozzle plate 35, a nozzle cover 36, and a nozzle guard 37. In the following description, a direction toward the nozzle plate 35 with respect to the head chips 33 and 34 in the Z direction is referred to as a lower direction, and a direction away from the nozzle plate 35 with respect to the head chips 33 and 34 is referred to as an upper direction.

The first head chip 33 is of a so-called edge-fire type that ejects ink from a leading end portion in a channel extending direction (Z direction) of an ejection channel 43 described later.

The first header 33 is formed by stacking the first actuator plate 41 and the first cover plate 42 in the Y direction.

The first actuator plate 41 is a so-called unipolar substrate in which the polarization direction is set to one direction in the thickness direction (Z direction). Further, a ceramic substrate including, for example, PZT (lead zirconate titanate) or the like is preferably used for the first actuator plate 41. The first actuator plate 41 may be formed by laminating two piezoelectric substrates having different polarization directions in the Z direction (so-called chevron type).

A plurality of

passages

43, 44 are provided in parallel on the surface of the first actuator plate 41 (the surface facing the first cover plate 42) at intervals in the X direction. Each of the

passages

43 and 44 is formed linearly in the Z direction and opens at least at the lower end surface of the first actuator plate 41. Each

channel

43, 44 is divided in the X direction by a drive wall 45 formed by the first actuator plate 41.

The plurality of

channels

43 and 44 are discharge channels 43 filled with ink and non-discharge channels 44 not filled with ink. The discharge channels 43 and the non-discharge channels 44 are alternately arranged in the X direction. Further, driving electrodes (not shown) are formed on the inner surfaces (driving walls 45) of the

channels

43 and 44 by vapor deposition or the like. The drive electrodes are applied with a drive voltage via a flexible printed circuit board not shown, and deform the drive walls 45 by a piezoelectric slip effect.

The first lid 42 is formed in a rectangular shape in a plan view seen from the Y direction. The first cover 42 is joined to the surface of the first actuator plate 41 with the upper end of the first actuator plate 41 exposed.

The first cover 42 has a common ink chamber 46 and a plurality of slits 47.

The common ink chamber 46 is formed at a position equal to the upper end portion of the discharge path 43 in the Z direction. The common ink chamber 46 is recessed toward the back surface of the first cover 42 (the surface facing the first actuator plate 41) and extends in the X direction. The ink flows into the common ink chamber 46 through the ink supply mechanism 3 (see fig. 1).

The slit 47 is formed in the common ink chamber 46 at a position facing the ejection path 43 in the Y direction. The slits 47 communicate the inside of the common ink chamber 46 with the inside of each discharge channel 43. On the other hand, the non-discharge passage 44 is not communicated with the common ink chamber 46.

The second head chip 34 is configured by stacking a second actuator plate 51 and a second cover plate 52 in the Y direction. The head chips 33 and 34 are integrated by bonding the back surfaces of the first actuator plate 41 and the second actuator plate 51 to each other. In the following description, the same reference numerals as those of the first head chip 33 are sometimes attached to the second head chip 34 to omit descriptions thereof, regarding the same configuration as that of the first head chip 33.

The discharge channels 43 and the non-discharge channels 44 of the second head chip 34 are arranged with a half pitch offset from the arrangement pitch of the discharge channels 43 and the non-discharge channels 44 of the first head chip 33. That is, the discharge channels 43 and the non-discharge channels 44 of the head chips 33 and 34 are arranged in a staggered manner. In this case, the ejection channels 43 of the first head chip 33 and the non-ejection channels 44 of the second head chip 34 face each other in the Y direction, and the non-ejection channels 44 of the first head chip 33 and the ejection channels 43 of the second head chip 34 face each other in the Y direction. Further, the arrangement pitch of the discharge channels 43 and the non-discharge channels 44 can be appropriately changed between the head chips 33 and 34. Further, between the head chips 33 and 34, the discharge channels 43 and the non-discharge channels 44 may be formed at the same position or different positions in the X direction.

The nozzle cover 36 is a plate-like member having a rectangular outer shape in plan view as viewed in the Z direction. The nozzle cover 36 is formed with a fitting hole 55 that penetrates the nozzle cover 36 in the Z direction. The first header chip 33 and the second header chip 34 are fitted together in the fitting hole 55. In the example of fig. 3, the head chips 33 and 34 are fitted into the fitting hole 55 so that the lower end surfaces thereof are flush with the lower end surface of the nozzle cover 36.

As shown in fig. 3, the nozzle plate 35 is fixed to the lower end surfaces of the head chips 33 and 34 and the nozzle cover 36 by, for example, bonding or the like. The nozzle plate 35 has a single-layer structure or a laminated structure made of a resin material (polyimide or the like), a metal material (SUS or the like), glass, or the like. The thickness of the nozzle plate 35 is, for example, about 50 μm.

The nozzle plate 35 has a plurality of nozzle rows (a first nozzle row 56 and a second nozzle row 57) extending in the Y direction. The

nozzle rows

56 and 57 extend in parallel with each other at intervals in the X direction.

The first nozzle row 56 has the above-described first nozzle holes 31 penetrating the nozzle plate 35 in the Z direction. The first nozzle holes 31 are formed in the nozzle plate 35 at positions facing the ejection channels 43 of the first head chips 33 in the Z direction, respectively. That is, the first nozzle holes 31 are linearly arranged at intervals in the Y direction.

The second nozzle row 57 has the above-described second nozzle holes 32 penetrating the nozzle plate 35 in the Z direction. The second nozzle holes 32 are formed in the nozzle plate 35 at positions facing the ejection channels 43 of the second head chip 34 in the Z direction, respectively. That is, the second nozzle holes 32 are linearly arranged at intervals in the Y direction. Further, each of the nozzle holes 31, 32 is formed in a tapered shape that tapers from above to below.

As shown in fig. 2 and 3, the nozzle guard 37 is formed by, for example, pressing a plate material such as SUS. The nozzle guard 37 is formed in a box shape opened upward. The nozzle guard 37 covers the nozzle plate 35 from below in a state of being fitted to the nozzle cover 36.

Exposure holes (first exposure holes 58 and second exposure holes 59) that penetrate the nozzle guard 37 in the Z direction are formed in the nozzle guard 37 at portions that face the

nozzle rows

56 and 57 in the Z direction. Each of the exposure holes 58 and 59 is formed in a slit shape extending in the Y direction. The

nozzle rows

56 and 57 are exposed to the outside through the corresponding exposure holes 58 and 59.

The lower surface of the nozzle guard 37 and the lower surface of the nozzle plate 35, which are exposed through the exposure holes 58 and 59, constitute the ejection surface of the inkjet head 5. In the inkjet head 5 of the present embodiment, since the nozzle plate 35 is covered with the nozzle guard 37, the nozzle holes 31 and 32 are opened at positions recessed upward with respect to the lower surface of the nozzle guard 37. That is, the discharge surface of the present embodiment is an uneven surface having a convex surface formed by the lower surface of the nozzle guard 37 and a concave surface formed by the lower surface of the nozzle plate 35.

Fig. 4 is a perspective view of the cleaning device 6.

In the printer 1 of the present embodiment, as shown in fig. 4, the plurality of ink jet heads 5 are mounted on the carriage 21 in a staggered state. In this case, the

nozzle rows

56 and 57 of the inkjet heads 5 adjacent in the Y direction partially overlap when viewed from the Y direction. However, the layout of each inkjet head 5 can be changed as appropriate. For example, the inkjet heads 5 may be arranged such that the

entire nozzle rows

56 and 57 of the inkjet heads 5 overlap when viewed from the Y direction. The number of inkjet heads 5 mounted on the carriage 21 can also be changed as appropriate.

As shown in fig. 1, the inkjet head 5 moves between the printing region S and the cleaning region C by the movement of the carriage 21 in the Y direction. The print area S is an area above the recording medium P (the transport mechanism 2). The inkjet head 5 reciprocates in the Y direction in the printing region S during a printing operation on the recording medium P.

The cleaning region C is a region located on one side in the Y direction with respect to the printing region S. The inkjet heads 5 move to the cleaning region C at the time of maintenance, at the time of driving stop, or the like.

< cleaning device >

As shown in fig. 4, the cleaning device 6 is provided below with respect to the inkjet heads 5 in the above-described cleaning area C. Specifically, the cleaning device 6 includes a base frame 60, a cleaning unit 61, a cleaning liquid supply mechanism 62 (see fig. 12), and a cleaning liquid tank 63 (see fig. 12).

The base frame 60 supports the cleaning unit 61 in a movable manner in the X direction. The base frame 60 is formed in a C-shape that opens upward in a front view seen from the X direction. A base rail 64 is disposed on a pair of base side wall portions 60a of the base frame 60 facing in the Y direction. The base rail 64 extends in the X direction at an upper end portion of each base side wall portion 60 a.

The cleaning unit 61 is disposed inside the base frame 60. The cleaning unit 61 includes a unit frame 65, a cover unit 66, and a blade unit 67.

The unit frame 65 is formed in a box shape opened upward. A pair of first side wall portions 65a facing in the Y direction among the unit frames 65 is supported on the base rail 64 so as to be slidable in the X direction.

The cleaning unit 61 is configured to be movable in the X direction with respect to the base frame 60 by operation of a drive mechanism, not shown. Specifically, the cleaning unit 61 moves between an opposing position overlapping each inkjet head 5 located in the cleaning region C and a retracted position (see fig. 15) retracted from each inkjet head 5 in a plan view seen from the Z direction. In addition, various configurations such as a belt, a chain, a trapezoidal screw, a ball screw, and the like can be adopted as the drive mechanism. In the following description, a direction toward the printing region S in the Y direction may be referred to as an inner side in the Y direction, and a direction toward the cleaning region C may be referred to as an outer side in the Y direction. In addition, a direction to the facing position among the X directions is referred to as one side, and a direction to the avoidance position is referred to as the other side.

Fig. 5 is a side view of the cleaning unit 61 viewed from one side in the X direction.

As shown in fig. 5, a unit guide 71 is disposed on a second side wall portion 65b of the unit frame 65 that faces in the X direction. The unit guide 71 is a cam groove that penetrates the second side wall portion 65b in the X direction. Two unit guides 71 are formed in each second side wall portion 65b at intervals in the Y direction. The unit guides 71 are formed in the same shape. Therefore, in the following description, one unit guide 71 will be described as an example, and the description of the other unit guides 71 will be omitted.

The unit guide 71 is formed in a step shape extending gradually upward as it goes outward in the Y direction. Specifically, the unit guide 71 is formed by connecting the lower portion 71a, the first connection portion 71b, the middle portion 71c, the second connection portion 71d, and the upper portion 71e in the Y direction.

The lower stage 71a, the intermediate stage 71c, and the upper stage 71e extend linearly in the Y direction.

The first connection portion 71b extends upward as going outward in the Y direction. The first connection portion 71b connects the lower stage portion 71a and the intermediate stage portion 71 c.

The second connection portion 71d extends upward as going outward in the Y direction. The second connection portion 71d connects the intermediate-stage portion 71c and the upper-stage portion 71 e.

As shown in fig. 4, the cover unit 66 is disposed inside the unit frame 65. The cover unit 66 includes a carriage cover mechanism 73 and a head cover mechanism 75.

The carriage cover mechanism 73 is a member for keeping the ejection surface of the inkjet head 5 wet. The carriage cover mechanism 73 has a cover frame 77, and a carriage cover 78 disposed on the cover frame 77.

As shown in fig. 5, a support pin 79 extending in the X direction penetrates the cover frame 77. Both ends of the support pin 79 in the X direction are inserted into the unit guides 71 facing each other in the X direction among the unit guides 71. Therefore, the cover unit 66 is configured to be movable in the Z direction in accordance with the sliding movement to the Y direction. Specifically, the cover unit 66 slides between an open position where the support pin 79 is located in the lower stage portion 71a, a carriage cover position where the support pin 79 is located in the middle stage portion 71c, and a hood cover position where the support pin 79 is located in the upper stage portion 71 e.

A stopper wall 81 capable of engaging with the carriage 21 in accordance with the movement of the carriage 21 is provided at a portion of the cover frame 77 located on the outer side in the Y direction. The stopper wall 81 protrudes upward from a portion of the cover frame 77 located on the outer side in the Y direction. The stopper wall portion 81 overlaps the carriage 21 when viewed from the Y direction when the cleaning unit 61 is at the facing position and the cover unit 66 is at the open position (hereinafter referred to as a cover initial position). When the cover initial position is set, the carriage 21 abuts (engages) the stopper wall portion 81 in accordance with the outward movement of the carriage 21 in the Y direction. Thereby, the cover frame 77 moves outward in the Y direction together with the carriage 21 in accordance with the movement of the carriage 21 outward in the Y direction. On the other hand, the stopper wall portion 81 is spaced from the carriage 21 with the movement of the carriage 21 to the Y direction inner side. This releases the engagement between the stopper wall 81 and the carriage 21.

A link mechanism 83 for moving the cover unit 66 inward in the Y direction is provided between the cover frame 77 and the unit frame 65. The link mechanism 83 includes a link bar 84 and an urging member 85.

The connecting bar 84 is a plate-like member extending in the Z direction. The link bar 84 is interposed between a first pivot shaft 86 coupled to the unit frame 65 and a second pivot shaft 87 coupled to the unit frame 65. Specifically, a first rotating shaft 86 extending in the X direction is inserted through the lower end portion of the link bar 84. The lower end portion of the link bar 84 is configured to be rotatable about the first rotation axis 86 with respect to the unit bottom wall portion 65c of the unit frame 65.

A guide hole 88 that penetrates the link bar 84 in the Y direction is formed in the upper end portion of the link bar 84. The guide hole 88 is an elongated hole extending in the extending direction of the link bar 84. A second rotation shaft 87 extending in the X direction is inserted through the guide hole 88. That is, the link bar 84 is configured to be rotatable about the second rotation axis 87 with respect to the cover unit 66 and to be relatively movable in the Z direction with respect to the cover unit 66.

The urging member 85 is interposed between the link bar 84 and the unit frame 65. The urging member 85 is, for example, a torsion coil spring. The biasing member 85 biases the cover unit 66 toward the Y-direction inner side (open position).

As shown in fig. 4, the carriage cover 78 is mounted on the unit frame 65. The carriage cover 78 is formed in a box shape opened upward.

Fig. 6 is a perspective view of the carriage cover 78.

As shown in fig. 6, a cleaning liquid flow path 90 through which a cleaning liquid flows is formed in the bottom wall portion of the carriage cover 78. The cleaning liquid flow path 90 mainly includes a cleaning liquid inlet flow path 100, a distribution flow path 101, a waste liquid flow path 102, and a cleaning liquid outlet flow path 103.

The cleaning liquid inlet flow path 100 extends in the Y direction on the other side in the X direction in the carriage cover 78. The cleaning liquid inlet passage 100 is inclined downward from the inside to the outside in the Y direction. An inlet port 104 for supplying a cleaning liquid into the cleaning liquid inlet flow path 100 is disposed at the Y-direction inner end of the cleaning liquid inlet flow path 100.

A plurality of distribution channels 101 are arranged at intervals in the Y direction. Each distribution channel 101 extends in the X direction. The other end of each distribution channel 101 in the X direction is connected to the cleaning liquid inlet channel 100. Further, each distribution channel 101 may be inclined downward as going from the other side to the one side in the X direction.

The waste liquid channel 102 includes a cover housing section 102a and a merged channel 102 b.

The cover accommodating portions 102a are formed between the distribution flow paths 101 adjacent in the Y direction. The hood accommodating portion 102a has a planar outer shape when viewed in the Z direction, which is sized to accommodate the hood mechanism 75. The cover accommodating portion 102a may be inclined downward as going from the other side to the one side in the X direction.

The merged channel 102b connects the cover accommodating sections 102a to each other on one side in the X direction with respect to the cover accommodating sections 102 a. A waste liquid port 105 is disposed in the merged channel 102b, and the waste liquid port 105 discharges the cleaning liquid flowing through the merged channel 102 b.

The cleaning liquid outlet flow path 103 extends in the Y direction on one side in the X direction in the carriage cover 78. The cleaning liquid outlet flow path 103 is connected to the distribution flow path 101 at least at both ends in the Y direction (for example, the distribution flow path 101 located at both ends in the Y direction). The cleaning liquid outlet flow path 103 is inclined downward as going from the inside to the outside in the Y direction. An outlet port 106 for discharging the cleaning liquid from the cleaning liquid outlet flow path 103 is disposed at the Y-direction outer end of the cleaning liquid outlet flow path 103. The outlet port 106 protrudes upward from the bottom wall portion of the cleaning liquid outlet passage 103. In this case, the discharge port of the outlet port 106 (the discharge port from the cleaning liquid outlet flow path 103) is located above the bottom wall portion of the cleaning liquid outlet flow path 103. The discharge port of the outlet port 106 may also be open on the peripheral wall portion of the carriage cover 78.

In the example of fig. 6, the waste liquid flow path 102 and the cleaning liquid inlet flow path 100, the waste liquid flow path 102 and the distribution flow path 101, and the waste liquid flow path 102 and the cleaning liquid outlet flow path 103 are partitioned by partition walls 107. Further, an absorbent 108 capable of absorbing the cleaning liquid may be disposed at least in the distribution flow path 101 in the cleaning liquid flow path 90. In this case, the absorber 108 can hold the cleaning liquid. Therefore, even if the cleaning liquid is biased in the cleaning liquid flow path 90 due to the inclination of the carriage cover 78 or the supply of the cleaning liquid is stopped, the cleaning liquid can be prevented from being exhausted at least in the distribution flow path 101. However, the absorber may be disposed in the entire cleaning liquid flow path 90.

As shown in fig. 4, in the cleaning liquid flow path 90, the portion other than the cover accommodating portion 102a is closed from above by the carriage inner plate 89.

Fig. 7 is a schematic configuration diagram of the inkjet head 5, the carriage 21, and the cover unit 66 as viewed from the X direction, showing a state in which the cover unit 66 is in the open position.

In the above-described open position, the upper end edge of the peripheral wall portion of the carriage cover 78 is located below the lower surface of the carriage 21 and the discharge surface of the inkjet head 5. This prevents the carriage cover 78 from interfering with the carriage 21 and the inkjet head 5.

Fig. 8 is a schematic configuration diagram of the inkjet head 5, the carriage 21, and the cover unit 66 as viewed from the X direction, showing a state where the cover unit 66 is at the carriage cover position.

As shown in fig. 8, the carriage cover 78 covers the carriage 21 from below in the above-described carriage cover position, and surrounds the periphery of the carriage 21. Thereby, all the nozzle holes 31, 32 of the inkjet head 5 are covered.

Fig. 9 is a schematic configuration diagram of the inkjet head 5, the carriage 21, and the cover unit 66 as viewed from the X direction, showing a state where the cover unit 66 is at the head cap position.

As shown in fig. 9, the carriage cover 78 is located above the carriage cover position in the head cover position.

As shown in fig. 4, the head cap mechanism 75 is used for cleaning the ejection surface of the inkjet head 5. The head cap mechanisms 75 are provided at positions facing the inkjet heads 5 in the Z direction at the cap initial position, among the bottom wall portions of the carriage cap 78. As shown in fig. 9, the headcap mechanism 75 abuts against the ejection surface of the inkjet head 5 from below when in the headcap position. Since each hood mechanism 75 has the same configuration, the hood mechanism 75 will be described below.

Fig. 10 is a perspective view of the hood mechanism 75.

As shown in fig. 10, the hood mechanism 75 has a first abutting unit 91, a second abutting unit 92, and a holder 93.

The holder 93 is fixed to a portion of the partition wall 107 that partitions the cover housing portion 102 a. The holder 93 holds the

respective contact units

91 and 92 in a state spaced upward from the bottom wall portion of the waste liquid channel 102.

The first contact unit 91 has a contact member 94A and a head piece 96A.

The abutting member 94A is constituted by a plurality of abutting

blocks

97A, 98A, 99A arranged in the Y direction. The push-against blocks 97A to 99A are a central push-against block 97A, a first outer push-against block 98A and a second outer push-against block 99A arranged on both sides in the Y direction with respect to the central push-against block 97A.

The center push block 97A is a porous member (sponge-like) having water absorption property formed by a foamed resin. The central abutting block 97A is formed in a rectangular parallelepiped shape with the X direction as the longer direction. The width of the center abutting block 97A in the Y direction is narrower than the width of the first exposure hole 58 (see fig. 3) in the Y direction. As shown in fig. 3 and 9, when the headcap mechanism 75 is in the headcap position, the upper surface of the center abutting block 97A faces the first nozzle row 56 in the Z direction on the ejection surface of the inkjet head 5.

As shown in fig. 10, the first outer abutting block 98A and the second outer abutting block 99A are porous members (sponge-like) having water-absorbing property formed by a foamed resin. The first outer abutting block 98A and the second outer abutting block 99A are lower in height in the Z direction than the center abutting block 97A. Thus, the upper surfaces of the first outer abutting block 98A and the second outer abutting block 99A are located lower than the upper surface of the central abutting block 97A. As shown in fig. 3 and 9, the first outer abutting block 98A and the second outer abutting block 99A are opposed to the portions (nozzle guards 37) of the ejection surface located on both sides in the Y direction with respect to the first nozzle row 56 in the Z direction when they are in the head covering position. In the example of fig. 10, the Y-direction width of each of the abutting blocks 97A to 99A is narrowed in the order of the first outer abutting block 98A, the center abutting block 97A, and the second outer abutting block 99A.

In the present embodiment, the center abutting block 97A is formed of a material harder than the first outer abutting block 98A and the second outer abutting block 99A in shore a hardness. Specifically, the first outer abutting block 98A is formed of a foamed resin of continuous bubbles (a structure in which a plurality of bubbles communicate with each other). On the other hand, the center abutting block 97A and the second outer abutting block 99A are formed of a single-bubble (a configuration in which a plurality of bubbles are independent of each other) foamed resin. However, if at least the first outer abutting block 98A among the abutting blocks 97A to 99A is formed of a continuous bubble, the central abutting block 97A and the second outer abutting block 99A may be formed of a continuous bubble.

The urging member 94A may not have water absorption properties if it is formed of at least an elastically deformable material. The abutting member 94A may not be divided into the plurality of abutting blocks 97A to 99A if it is formed in an uneven shape following the concave surface of the ejection surface where the nozzle plate 35 is exposed and the convex surface of the nozzle guard 37 is exposed.

The head sheet 96A is a sheet having water absorption properties formed of a nonwoven fabric, woven fabric, or the like. The head piece 96A covers both the upper side and both sides in the Y direction of the abutting member 94A (the abutting blocks 97A to 99A). The portion of the head piece 96A located above the abutting member 94A abuts against the ejection surface of the inkjet head 5 from below when the headcap mechanism 75 is in the headcap position.

As shown in fig. 6 and 10, the first end (outer end in the Y direction) of the head piece 96A is immersed in the cleaning liquid in the distribution flow path 101. On the other hand, the second end (the inner end in the Y direction) of the head piece 96A is spaced from the waste liquid channel 102. Further, the mass per unit area (m) of the head piece 96A²) The weight (g)) of (A) is preferably, for example, 70g/m²The above. Thus, the head piece 96A has a smaller opening ratio (area of the opening per unit area) than the upper end surfaces of the abutting blocks 97A to 99A.

As shown in fig. 10, the second abutment unit 92 is disposed on the inner side in the Y direction with respect to the first abutment unit 91. In the following description, regarding the same configuration as the first contact unit 91 in the second contact unit 92, the same reference numeral as that of the first contact unit 91 is denoted by "B" and the description thereof may be omitted.

The second contact unit 92 includes a pushing member 94B and a head piece 96B, similarly to the first contact unit 91.

As shown in fig. 3 and 9, the center abutting block 97B of the second abutting unit 92 faces the second nozzle row 57 in the Z direction on the ejection surface of the inkjet head 5 when the headcap mechanism 75 is at the headcap position.

The outer abutting

blocks

98B and 99B face portions (nozzle guards 37) on the ejection surface on both sides in the Y direction with respect to the second nozzle row 57 when the outer abutting blocks are in the head covering position.

The head piece 96B covers both the upper side and both sides in the Y direction of the abutting member 94B (the abutting blocks 97B to 99B). The portion of the head piece 96B located above the pushing member 94B abuts against the ejection surface of the inkjet head 5 from below when the headcap mechanism 75 is in the headcap position. The first end (the inner end in the Y direction) of the head piece 96B is immersed in the cleaning liquid in the distribution flow path 101. On the other hand, the second end (outer end in the Y direction) of the head piece 96B is spaced from the waste liquid channel 102. Further, a partition portion that partitions the first abutting unit 91 and the second abutting unit 92 may be provided between the first abutting unit 91 and the second abutting unit 92.

As shown in fig. 4, the squeegee unit 67 is disposed on one side in the X direction with respect to the unit frame 65. The blade unit 67 wipes off the discharge surface of each inkjet head 5 while the cleaning unit 61 moves from the facing position to the off position.

Fig. 11 is a sectional view of the squeegee unit 67 corresponding to the line XI-XI in fig. 4.

The squeegee unit 67 includes a box-shaped squeegee frame 110. A squeegee pool is attached to the other side wall portion of the squeegee frame 110 on the other side in the X direction. The squeegee pool 111 is formed in a box shape having an opening at the upper side. The cleaning liquid supplied from the cleaning liquid supply mechanism 62 is stored in the blade reservoir 111. The other end portion of the squeegee pool 111 in the X direction is fixed to a second side wall portion 65b positioned on one side in the X direction in the unit frame 65 (see fig. 4 and the like). Thereby, the squeegee frame 110 is disposed at intervals in the X direction with respect to the unit frame 65. Further, a float sensor 116 (see fig. 12) for detecting the liquid level of the cleaning liquid is provided in the squeegee pool 111.

As shown in fig. 4, a strut (stay) extending to the other side in the X direction is attached to the side wall portions of the squeegee frame 110 facing each other in the Y direction. Between the support columns 112, a support shaft 113 extending in the Y direction is bridged. The support shaft 113 is supported by the stay 112 so as to be rotatable about the Y direction. A scraper mechanism 115 is provided on the support shaft 113. The squeegee mechanisms 115 are provided four at intervals in the Y direction corresponding to the ink jet heads 5. In the following description, one squeegee mechanism 115 is described among the plurality of squeegee mechanisms 115.

As shown in fig. 11, the squeegee mechanism 115 includes a squeegee holder 120, a first squeegee 121, and a second squeegee 122.

The blade holder 120 is attached to the support shaft 113 in a state of protruding upward with respect to the support shaft 113.

The first blade 121 is formed of a material (rubber, resin, or the like) having flexibility. The first blade 121 is formed in a plate shape. The first blade 121 is fixed to the blade holder 120 so as to extend in the Z direction. The first blade 121 has a distal end (upper end) that protrudes upward from the blade holder 120 and is disposed at a height that allows sliding contact with the discharge surface of the inkjet head 5.

The second blade 122 is formed of a material (rubber, resin, or the like) having flexibility. The second blade 122 is formed in a plate shape. The second blade 122 is fixed to the blade holder 120 so as to extend upward with going to one side in the X direction. The distal end of the second blade 122 may be disposed at a height that allows sliding contact with the discharge surface of the inkjet head 5. In the example of fig. 11, the tip end of the second blade 122 is located below the tip end of the first blade 121. The distal end portion of the second blade 122 can be brought into contact with and separated from the distal end portion of the first blade 121 by the flexural deformation of the

blades

121 and 122.

The space surrounded by the squeegee holder 120 and the

squeegees

121 and 122 in the squeegee mechanism 115 constitutes a first suction chamber 125. The

scrapers

121 and 122 may be made of the same material or different materials. Although the first suction chamber 125 is formed by the squeegee holder 120 and the

squeegees

121 and 122 in the present embodiment, the first suction chamber 125 may be defined by a plurality of squeegees of three or more pieces.

The squeegee mechanism 115 is movable between a dipping position (spacing position) and a wiping position in accordance with the rotation of the support shaft 113. At the dipping position, at least the tip end portions of the

scrapers

121 and 122 of the scraper mechanism 115 are dipped in the cleaning liquid in the scraper pool 111 (see fig. 14). On the other hand, at the wiping position, at least the tip end portion of the first blade 121 of the blade mechanism 115 is disposed at a height capable of sliding contact with the discharge surface of the inkjet head 5.

The blade holder 120 is formed with a first communication hole 126 for communicating the inside and outside of the first suction chamber 125. The first communication hole 126 penetrates the squeegee holder 120 in the X direction. The connection pipe 127 is connected to the first connection hole 126. The connection pipe 127 protrudes from the squeegee holder 120 toward one side in the X direction. The first communication hole 126 may be a single long hole having the Y direction as the major axis, or may be formed by a plurality of through holes spaced apart in the Y direction.

Here, the internal space of the squeegee frame 110 constitutes the second suction chamber 132. The second suction chamber 132 can communicate with the inside of the first suction chamber 125 through the second communication hole 130 formed in the other side wall portion of the squeegee frame 110 and the connection pipe 127. The connection pipe 127 may be connected to the squeegee holder 120 (the first communication hole 126) or may be connected to the squeegee frame 110 (the second communication hole 130).

A suction hole 133 for communicating the inside and outside of the blade frame 110 is formed in one side wall portion of the blade frame 110 on one side in the X direction. A plurality of suction holes 133 are formed at intervals in the Y direction in the upper portion of the one side wall portion. A plurality of blowers 135 covering the suction holes 133 from one side in the X direction are attached to one side wall portion of the squeegee frame 110. The blowers 135 communicate with the second suction chamber 132 through the suction holes 133. Further, on the upper wall portion of the squeegee frame 110, a blocking plate 136 that partitions the suction hole 133 and the second communication hole 130 in the X direction is provided. Further, an absorbent body (not shown) having water absorption properties may be disposed in the second suction chamber 132 at a portion located below the blocking plate 136.

Fig. 12 is a schematic configuration diagram of the cleaning liquid supply mechanism 62.

As shown in fig. 6 and 12, the cleaning liquid supply mechanism 62 supplies the cleaning liquid stored in the cleaning liquid storage tank 63 to the cleaning liquid flow path 90 and the blade reservoir 111. Specifically, the cleaning liquid supply mechanism 62 includes a supply pipe 141, a connection pipe 142, a first waste liquid pipe 143, a second waste liquid pipe 144, and a cleaning liquid pump 145 disposed on the supply pipe 141.

The supply pipe 141 connects the cleaning liquid reservoir 63 and the cleaning liquid inlet passage 100 (see fig. 6) of the cleaning liquid passage 90. Specifically, a first end of the supply pipe 141 is connected to the cleaning liquid storage tank 63. A second end of the supply pipe 141 is connected to the inlet port 104.

The cleaning liquid pump 145 pressurizes the inside of the supply pipe 141 to send the cleaning liquid to the cleaning liquid flow path 90 through the supply pipe 141.

The connection pipe 142 connects the cleaning liquid outlet flow path 103 of the cleaning liquid flow path 90 and the blade reservoir 111. Specifically, a first end of the connection pipe 142 is connected to the outlet port 106 of the cleaning liquid outlet passage 103. The second end of the connecting tube 142 is connected to a pool port 148 provided in the squeegee pool 111.

The first waste liquid pipe 143 connects the waste liquid flow path 102 of the cleaning liquid flow path 90 and the waste liquid tank 150. Specifically, a first end of the first waste liquid pipe 143 is connected to the waste liquid port 105 of the waste liquid channel 102 shown in fig. 6. The second end of the first waste liquid pipe 143 is connected to the waste liquid tank 150. An opening/closing valve 151 is provided in the first waste liquid pipe 143. The opening/closing valve 151 may not be provided.

A second waste pipe 144 connects between the squeegee reservoir 111 and a waste reservoir 150. Specifically, a first end of the second waste liquid pipe 144 is connected to a waste liquid port, not shown, provided in the squeegee pool 111. A second end of the second waste pipe 144 is connected to the waste tank 150. An opening/closing valve 152 is provided in the second waste liquid pipe 144.

[ method of operating Printer ]

Next, an operation method of the printer 1 will be described. In the following description, the printing method, wiping method, carriage cover method, head cover method, and cleaning liquid supply method will be described in order, followed by a description of the printing standby method.

< printing method >

First, a printing method on the recording medium P will be described.

As shown in fig. 1, when the printer 1 is operated, the raster roller 11 of the transport mechanism 2 rotates, and the recording medium P is transported in the X direction between the raster roller 11 and the pinch roller 12. At the same time, the driving motor 26 rotates the pulley 24 to move the endless belt 25. Thereby, the carriage 21 reciprocates in the Y direction while being guided by a guide rail, not shown.

During this period, as shown in fig. 3, in each inkjet head 5, a driving voltage is applied to the driving electrodes of the head chips 33 and 34. This causes the thickness of the driving wall 45 to be slidably deformed, thereby generating a pressure wave in the ink filled in the discharge passage 43. The pressure wave increases the internal pressure of the discharge channel 43, and the ink is discharged through the nozzle holes 31 and 32. Then, various kinds of information are recorded on the recording medium P by the ink hitting on the recording medium P.

< wiping method >

Next, a wiping method by the discharge surface of the blade unit 67 will be described. In the following description, the cover unit 66 is at the cover initial position, and the squeegee unit 67 is at the wiping position. Further, in the hood initial position, the hood unit 66 is held in the open position.

First, the endless belt 25 shown in fig. 1 is moved to move the carriage 21 to the cleaning area C. At this time, as shown in fig. 7, the carriage 21 is moved from the inner side in the Y direction to a position (wiping standby position) where it abuts against the stopper wall portion 81. Thus, as shown in fig. 4, each ink jet head 5 is disposed at a position equal to the corresponding squeegee mechanism 115 in the Y direction and faces the corresponding head cap mechanism 75 in the Z direction.

FIG. 13 is a movement explanatory diagram for explaining the wiping method.

Subsequently, as shown in fig. 13, the blower 135 is driven. Then, the air in the second suction chamber 132 is sucked through the suction hole 133, and the air in the first suction chamber 125 is sucked through the second communication hole 130, the connection pipe 127, and the first communication hole 126. This maintains the negative pressure in the first suction chamber 125 and the second suction chamber 132.

After that, the cleaning unit 61 is moved to the off position. Then, when the squeegee mechanism 115 passes through the inkjet head 5, at least the first squeegee 121 slides on the discharge surface of the inkjet head 5. This wipes off the discharge surface of the ink jet head 5.

While the squeegee mechanism 115 is in sliding contact with the discharge surface of the inkjet head 5, the

blades

121 and 122 are flexed and deformed, and the distal ends of the

blades

121 and 122 are spaced apart from each other. Thus, the inside and outside of the first suction chamber 125 communicate with each other through the gap between the distal ends of the

scrapers

121 and 122. At this time, since the inside of the first suction chamber 125 is maintained at a negative pressure, the ink adhering to the

blades

121 and 122 and the discharge surface is sucked into the first suction chamber 125 by the tip portions of the

blades

121 and 122. The ink sucked into the first suction chamber 125 flows into the second suction chamber 132 through the connection tube 127. This enables cleaning of the discharge surface and removal of ink adhering to the discharge surface.

Fig. 14 and 15 are operation explanatory diagrams for explaining the wiping method.

As shown in fig. 14 and 15, the driving of the blower 135 is stopped at the time when the cleaning unit 61 reaches the off position. Next, the squeegee mechanism 115 is moved to the dipping position by rotating the support shaft 113. Then, the distal ends of the

blades

121 and 122 are immersed in the cleaning liquid in the blade reservoir 111. This enables the cleaning of the

blades

121 and 122 to remove ink adhering to the

blades

121 and 122.

After that, the wiping method by the blade unit 67 is completed by returning the cleaning unit 61 to the opposing position. Further, the carriage 21 may be returned to the printing region S before the cleaning unit 61 is returned to the facing position.

< carriage cover method >

Next, a carriage cover method by the carriage cover mechanism 73 will be described. In the following description, the description is started from the time when the carriage 21 is at the wiping standby position of the cleaning region C and the cap unit 66 is at the cap initial position (the cap unit 66 is at the open position).

First, as shown in fig. 7, the carriage 21 is moved outward in the Y direction from the wiping standby position. Then, the cover unit 66 is pressed by the carriage 21 via the stopper wall portion 81 toward the outside in the Y direction (the direction against the urging force of the urging member 85). Thereby, the cover unit 66 moves outward in the Y direction together with the carriage 21 as the carriage 21 moves outward in the Y direction.

Fig. 16 is an operation explanatory diagram for explaining the carriage cover method.

As shown in fig. 16, in the process of moving the cover unit 66 from the open position to the outside in the Y direction, the support pin 79 moves to the outside in the Y direction in the unit guide 71. Specifically, the support pin 79 passes from the lower stage portion 71a to the intermediate stage portion 71c through the first connecting portion 71b in the unit guide 71. The support pin 79 moves upward as it goes outward in the Y direction during the movement in the first connection portion 71 b. Thereby, the cover unit 66 moves upward as going outward in the Y direction. Then, the cover unit 66 reaches the carriage cover position at the timing when the support pin 79 reaches the middle stage portion 71 c. As shown in fig. 8, in the carriage cover position, the carriage cover 78 approaches the carriage 21, covering the carriage 21 from below to cover all the nozzle holes 31, 32 of the inkjet head 5 from below. This suppresses drying of the ink in the nozzle holes 31 and 32, and maintains the wet state of the ink. In the carriage cover position, the

head pieces

96A and 96B do not abut on the ejection surface.

Further, in order to move the cover unit 66 from the carriage cover position to the open position, the carriage 21 is moved to the inner side in the Y direction (wiping standby position). Then, the cover unit 66 moves inward in the Y direction together with the carriage 21 by the biasing force of the biasing member 85, and moves downward as it goes inward in the Y direction. Thereby, as shown in fig. 7, the cover unit 66 moves to the open position.

< method of hood >

Next, a hood method by the hood mechanism 75 will be described. In the following description, the cover unit 66 (carriage 21) is described from the time when it is at the carriage cover position.

First, as shown in fig. 8, the carriage 21 is moved outward in the Y direction. Then, the cover unit 66 is pressed by the carriage 21 via the stopper wall portion 81 toward the outside in the Y direction (the direction against the urging force of the urging member 85). Thereby, the cover unit 66 moves outward in the Y direction together with the carriage 21 as the carriage 21 moves outward in the Y direction.

Fig. 17 is an operation explanatory diagram for explaining a hood method.

As shown in fig. 17, in the process of moving the cover unit 66 outward in the Y direction from the carriage cover position, the support pin 79 moves outward in the Y direction within the unit guide 71. Specifically, the support pin 79 passes from the intermediate-stage portion 71c to the upper-stage portion 71e through the second connection portion 71d in the unit guide 71. The support pin 79 moves upward as it goes outward in the Y direction while moving in the second connection portion 71 d. Thereby, the cover unit 66 moves upward as going outward in the Y direction. Then, the cover unit 66 reaches the hood position at the timing when the support pins 79 reach the upper stage portion 71 e.

As shown in fig. 9, in the head cap position, each head cap mechanism 75 abuts against the discharge surface of each inkjet head 5 from below. Specifically, in each head cap mechanism 75, the pushing member 94A of the first contact unit 91 contacts the discharge surface of the ink jet head 5 via the head piece 96A. At this time, the center abutting block 97A abuts on the first nozzle row 56 (nozzle plate 35) through the first exposure hole 58. On the other hand, the outer abutting

pieces

98A and 99A abut on the lower surface of the nozzle guard 37.

In each head cap mechanism 75, the pushing member 94B of the second contact unit 92 contacts the discharge surface of the ink jet head 5 via the head piece 96B. At this time, the center push block 97B abuts on the second nozzle row 57 (nozzle plate 35) through the second exposure hole 59. On the other hand, the outer abutting

pieces

98B and 99B abut on the lower surface of the nozzle guard 37.

In the head cap position, the ink adhering to the discharge surface is dissolved by the cleaning liquid impregnated into the

head pieces

96A and 96B, and then absorbed by the

head pieces

96A and 96B. This enables cleaning of the discharge surface. Further, the

abutment units

91, 92 can also close (block) the nozzle holes 31, 32 in the head cap position.

As shown in fig. 6 and 10, the first end portions of the

head pieces

96A and 96B are immersed in the cleaning liquid in the distribution flow path 101. Therefore, the cleaning liquid in the distribution flow path 101 is infiltrated into the

head pieces

96A and 96B from the first end by capillary action or the like. The cleaning liquid impregnated in the

head pieces

96A and 96B permeates from the first end portion toward the second end portion. Further, a part of the cleaning liquid reaching the second end portions of the

head pieces

96A, 96B flows to the cap housing portion 102a of the waste liquid flow path 102. As shown in fig. 6, the cleaning liquid flowing into the cover housing section 102a flows into one side in the X direction in the cover housing section 102a, and then flows into the waste liquid port 105 through the merged channel 102 b. The cleaning liquid flowing into the waste liquid port 105 is discharged to the waste liquid tank 150 through the first waste liquid pipe 143 shown in fig. 12.

As shown in fig. 7 and 8, the carriage 21 is moved inward in the Y direction (wiping standby position) in order to move the cover unit 66 from the cover position to the open position. Then, the cover unit 66 moves inward in the Y direction together with the carriage 21 by the biasing force of the biasing member 85, and moves downward as it goes inward in the Y direction. Thereby, the cover unit 66 moves to the open position.

< cleaning liquid supply method >

Next, a method of supplying the cleaning liquid to the cleaning liquid flow path 90 and the blade reservoir 111 will be described.

First, as shown in fig. 12, the cleaning liquid pump 145 is driven, whereby the cleaning liquid stored in the cleaning liquid tank 63 flows through the supply pipe 141. As shown in fig. 6, the cleaning liquid flowing through the supply pipe 141 is supplied to the cleaning liquid inlet passage 100 through the inlet port 104. The cleaning liquid supplied into the cleaning liquid inlet flow path 100 is distributed to the distribution flow path 101 while flowing outward in the Y direction in the cleaning liquid inlet flow path 100. Further, as described above, a part of the cleaning liquid flowing through the distribution flow path 101 penetrates the

head pieces

96A and 96B to clean the discharge surfaces.

On the other hand, the cleaning liquid having passed through the distribution flow path 101 flows into the cleaning liquid outlet flow path 103. The cleaning liquid flowing into the cleaning liquid outlet flow path 103 flows inward in the Y direction through the cleaning liquid outlet flow path 103. When the liquid level of the cleaning liquid flowing through the cleaning liquid outlet passage 103 becomes higher than the discharge port of the outlet port 106, the cleaning liquid flows into the outlet port 106. The cleaning liquid flowing into the outlet port 106 flows toward the blade pool 111 in the connection pipe 142 by the head value of the liquid surface of the cleaning liquid in the cleaning liquid outlet flow path 103 and the liquid surface of the cleaning liquid in the blade pool 111. Then, the cleaning liquid flowing in the connection pipe 142 is supplied into the squeegee pool 111 through the pool port 148. The cleaning liquid supplied to the blade reservoir 111 is supplied to the

cleaning blades

121, 122 as described above.

As shown in fig. 12, the operation of the cleaning liquid pump 145 can be controlled based on the detection result (the liquid level of the squeegee pool 111) of the float sensor 116 provided in the squeegee pool 111. Specifically, it is first determined whether or not the liquid level of the squeegee pool 111 is equal to or higher than a predetermined value. Next, when the liquid surface height of the squeegee pool 111 is smaller than a predetermined value (for example, the liquid surface height at which the

squeegees

121 and 122 are not immersed), the cleaning liquid pump 145 is driven. On the other hand, when the liquid level of the squeegee pool 111 is equal to or higher than the predetermined value, the driving of the cleaning liquid pump 145 is stopped. This enables the cleaning liquid to be accurately supplied to the cleaning liquid flow path 90 and the blade pool 111.

As shown in fig. 12, the cleaning liquid in the waste liquid channel 102 is discharged to the waste liquid tank 150 by appropriately opening the on-off valve 151 provided in the first waste liquid pipe 143. Further, by appropriately closing the on-off valve 152 provided in the second waste liquid pipe 144, the cleaning liquid supplied to the squeegee pool 111 is discharged to the waste liquid tank 150.

< printing standby method >

Next, the standby operation before the start of the discharge operation of the ink jet head 5 will be described. Fig. 18 is a flowchart for explaining a printing standby method. In the following description, the cover unit 66 is at the cover initial position, the squeegee unit 67 is at the wiping standby position, and the squeegee mechanism 115 is at the dipping position. In the non-discharge state of the inkjet head 5, the ink in the nozzle holes 31 and 32 forms an appropriate (concave) meniscus by surface tension or the like acting on the inner surfaces of the nozzle holes 31 and 32. That is, in the ink jet head 5, by maintaining the pressure in the discharge path 43 at a desired negative pressure (for example, the meniscus pressure Pa), the meniscus is maintained, and ink is not discharged. On the other hand, when the pressure in the discharge channel 43 is set to a desired positive pressure state, the meniscus is broken and ink is discharged from the nozzle holes 31 and 32.

As shown in fig. 18, in step S01, the cleaning liquid is supplied to the cleaning liquid flow path 90 and the blade reservoir 111 by the same method as the above-described cleaning liquid supply method. Specifically, the cleaning liquid in the cleaning liquid reservoir 63 is supplied to the distribution flow path 101 of the cleaning liquid flow path 90, and then supplied to the blade reservoir 111 through the distribution flow path 101.

In step S02, it is determined whether or not the liquid level of the squeegee pool 111 is equal to or higher than a predetermined value based on the detection result of the float sensor 116 provided in the squeegee pool 111.

If the determination result of step S02 is "no" (the liquid level is less than the predetermined value), it is determined that the cleaning liquid has not been sufficiently supplied into the distribution flow path 101 and the blade pool 111. In this case, the process returns to step S01 to continue the supply of the cleaning liquid.

If the determination result in step S02 is yes (the liquid level is equal to or higher than the predetermined value), it is determined that the cleaning liquid has been sufficiently supplied into the distribution flow path 101 and the blade pool 111. In this case, the process proceeds to step S03.

In step S03, the drive of the cleaning liquid pump 145 is stopped.

Next, in step S04, the squeegee mechanism 115 is moved from the dipping position to the wiping position.

In step S05, purging of the inkjet head 5 is performed. The purge is an operation for restoring the discharge performance to the level before printing. Specifically, by pressurizing the inside of the discharge channel 43, the pressure (for example, purge pressure Pb) in the discharge channel 43 is maintained to such an extent that the meniscus is broken and ink leaks from the nozzle holes 31 and 32. That is, the purge pressure Pb is set to be greater than the meniscus pressure Pa (Pb > Pa). This causes dust, air bubbles, ink whose viscosity has increased due to drying, and the like that have entered the nozzle holes 31 and 32 to be discharged from the nozzle holes 31 and 32. The ink discharged from the nozzle holes 31 and 32 is absorbed by the

head pieces

96A and 96B and the abutting

members

94A and 94B of the head cap mechanism 75, and discharged to the cap housing portion 102 a.

After the purge is performed for a predetermined time, the process proceeds to step S06.

Next, in step S06, the pressure in the discharge passage 43 is set to the standby pressure Pc. The standby pressure Pc is a pressure at which the ink bulges convexly from the nozzle holes 31 and 32 and does not leak from the nozzle holes 31 and 32. That is, the standby pressure Pc is set to be greater than the meniscus pressure Pa and smaller than the purge pressure Pb. The standby pressure Pc may be set to be equal to the atmospheric pressure.

In step S07, the squeegee mechanism 115 is moved to the wiping position, and the ejection surface of the inkjet head 5 is wiped by the same wiping method as described above. Specifically, the blower 135 is driven and the cleaning unit 61 is moved to the off position. This allows wiping of the ink adhering to the

blades

121 and 122 and the discharge surface, and wiping of the discharge surface of the inkjet head 5 by the

blades

121 and 122. In step S07, the pressure in the discharge passage 43 is also maintained at the standby pressure Pc. Therefore, after wiping by the squeegee mechanism 115, the ink is again held in a state of being blown out from the nozzle holes 31, 32.

In step S08, the squeegee mechanism 115 is moved to the dipping position again.

In step S09, the cleaning unit 61 is moved to the facing position.

In step S10, the cover unit 66 is moved to the carriage cover position by the same method as the carriage cover method described above. Specifically, by moving the carriage 21 outward in the Y direction from the wiping standby position, the cover unit 66 moves outward in the Y direction together with the carriage 21 and moves upward. Thereby, the carriage cover 78 covers the carriage 21 from below to cover all the nozzle holes 31, 32 of the inkjet head 5 from below.

In step S11, the carriage cover position is held for a predetermined time (for example, about 60 seconds). In this case, it is also possible to perform spitting (an operation of forcibly ejecting ink) and wiping (an operation of deforming the driving wall 45 to such an extent that ink is not ejected).

Thereafter, in step S12, the pressure in the discharge passage 43 is returned to the meniscus pressure Pa.

Thus, the main routine is ended. Further, the main routine may be ended while the pressure in the discharge passage 43 is maintained at the standby pressure Pc.

As described above, in the present embodiment, the blade unit 67 and the cap unit 66 are arranged in a sub-scanning direction (X direction) orthogonal to the main scanning direction (Y direction) of the inkjet head 5, and are configured to be integrally movable in the X direction.

According to this configuration, while the cleaning unit 61 is moving in the X direction, the discharge surface of the inkjet head 5 can be wiped off by sliding the squeegee mechanism 115 against the discharge surface. In particular, the printer 1 can be downsized in the Y direction compared to a configuration in which the squeegee unit 67 and the cover unit 66 are arranged in the Y direction as in the related art. In this case, even if the squeegee mechanism 115 is provided corresponding to the plurality of inkjet heads 5 aligned in the Y direction, the printer 1 can be suppressed from being large-sized. Therefore, the printer 1 can be provided which is small in size and short in cleaning time.

In the present embodiment, the carriage cover mechanism 73 covers the nozzle holes 31 and 32 of the inkjet head 5 at the carriage cover position of the cover unit 66. With this configuration, it is possible to maintain the wet state of the ink by suppressing the drying of the ink in the nozzle holes 31 and 32 during the printing standby time or the like (when the standby time in the cleaning region C is short).

In the present embodiment, the head cap mechanism 75 impregnated with the cleaning liquid is configured to abut against the discharge surface of the ink jet head 5 at the head cap position of the cap unit 66. With this configuration, the discharge surface can be cleaned with the cleaning liquid impregnated in the head cover mechanism 75. This enables ink and the like adhering to the discharge surface to be removed, and the discharge performance to be improved.

In this way, in the present embodiment, since the cover unit 66 is configured to be movable to both the carriage cover position and the head cap position, an optimum cover state can be selected according to the standby state and the cleaning content of the printer 1. For example, the carriage cover may be selected when the standby time is short, and the head cover may be selected when the standby time is long and the recovery of the discharge performance is aimed. As a result, not only the cleaning operation is simplified and the amount of ink used in the cleaning operation is suppressed, but also drying of the ink can be suppressed, for example, as compared with a case where ink is discharged through the nozzle holes at each cleaning.

In the present embodiment, the cap unit 66 is configured to be movable in the Z direction in accordance with the forward movement of the inkjet head 5 in the Y direction in a state where the inkjet head 5 is engaged with the stopper wall portion 81.

According to this configuration, the cover unit 66 can be moved to the open position, the carriage cover position, and the head cap position in conjunction with the movement of the inkjet head 5 in the Y direction. This can simplify the configuration and reduce the cost, compared to the case where the ink jet head 5 and the cap unit 66 are moved by separate driving mechanisms.

In the present embodiment, since the squeegee mechanism 115 is movable between the wiping position and the dipping position, interference between the ink jet head 5 and the squeegee mechanism 115 can be suppressed when the cap initial position is returned after wiping of the discharge surface. This can prevent the ink adhering to the squeegee mechanism 115 from adhering to the inkjet head 5 again when the ink returns during the wiping operation.

In particular, in the present embodiment, a configuration is adopted in which the squeegee mechanism 115 is disposed downward in the dipping position. According to this configuration, for example, in a configuration in which printing operation is performed while ultraviolet light is irradiated, as in the case where ultraviolet-curable UV ink is used as the ink, the squeegee mechanism 115 is less likely to be irradiated with ultraviolet light. Therefore, the UV ink adhering to the squeegee mechanism 115 can be prevented from being hardened, and the UV ink adhering to the squeegee mechanism 115 can be quickly removed.

In the present embodiment, since the cleaning device 6 is provided, the printer 1 can be provided which is small in size, excellent in printing characteristics, and high in reliability.

(second embodiment)

Next, a second embodiment of the present invention will be explained. Fig. 19 is a schematic perspective view of a printer 220 according to the second embodiment. In the following description, the same reference numerals are given to the same components as those in the first embodiment, and the description thereof is omitted.

In the printer 220 shown in fig. 19, a carriage 201 is supported on a guide rail 202 so as to be movable in the Y direction. The printer 220 includes a linear encoder 203 and a cleaning position detecting unit 204.

The linear encoder 203 is a member for detecting the position of the carriage 201 in the Y direction. The linear encoder 203 is, for example, an optical linear encoder. Specifically, the linear encoder 203 includes a linear scale 205 provided on the guide rail 202, and a sensor unit 206 provided on the carriage 201.

The linear scale 205 is formed in a plate shape extending in the Y direction along the guide rail 202. A plurality of scales are attached to the linear scale 205 at intervals in the Y direction.

The sensor unit 206 includes, for example, a light emitting unit and a light receiving unit. In the sensor portion 206, the light emitted from the light emitting portion and transmitted through the scale is received by the light receiving portion. The detection result of the sensor unit 206 is output to a control unit (not shown) of the printer 220 as an encoder pulse.

The printer 220 of the present embodiment counts encoder pulses output from the sensor unit 206 in the control unit, and calculates the position of the carriage 201 in the Y direction. Then, the control unit controls the driving of the drive motor 26 (e.g., a servo motor), the ink discharge timing of the inkjet head 5, and the like based on the calculated position information of the carriage 201. The linear encoder 203 may be of a magnetic type, for example.

The cleaning position detecting means 204 is a means for detecting that the carriage 201 is located at the Y-direction reference position. The "Y-direction reference position" is, for example, a position that is a predetermined distance inward in the Y direction with respect to the cleaning region C. The amount of movement in the Y direction from the Y-direction reference position to the cleaning region C (wiping standby position) is stored in the control unit in advance as the number of counts of encoder pulses.

The cleaning position detecting member 204 is, for example, a photo interrupter sensor (photo interrupter sensor). Specifically, the cleaning position detecting member 204 includes a detecting piece 210 provided on the carriage 201 and a sensor portion 211 provided on the guide rail 202.

The sensor unit 211 includes a light emitting unit and a light receiving unit. The detection piece 210 can pass between the light emitting portion and the light receiving portion. The sensor portion 211 detects, for example, an on state in which the light receiving portion receives light emitted from the light emitting portion, and an off state in which the light emitted from the light emitting portion is blocked by the detection piece 210. The control unit determines that the carriage 201 is positioned at the Y-direction reference position when the detection result of the sensor unit 211 is in the off state. The control unit moves the carriage 201 to the cleaning area C by moving the carriage 201 by a predetermined distance with respect to the Y-direction reference position based on the detection result of the cleaning position detecting unit 204 and the detection result of the linear encoder 203.

Fig. 20 is a perspective view of a cleaning area C in the printer 220 according to the second embodiment. Fig. 21 is a side view of the cleaning unit 230 according to the second embodiment as viewed from one side in the X direction.

As shown in fig. 20 and 21, the carriage 201 mainly includes a carriage base 215 that supports the inkjet head 5, a pair of

side plates

216a and 216b that stand upward from the carriage base 215, and a rear plate 217.

Fig. 22 is a sectional view corresponding to line XXII-XXII in fig. 20.

As shown in fig. 22, the carriage base 215 includes a lower base 215a and an upper base 215b connected to an upper side of the lower base 215 a. The plan view outer shape of the lower base portion 215a is formed in a size that can enter the carriage cover 78. Further, a chamfered portion 219 is formed on the outer peripheral edge of the lower end of the lower base portion 215a (the outer peripheral edge of the end portion on the cleaning unit 230 side). The chamfered edge 219 is not limited to a flat chamfered edge, and may be a rounded chamfered edge. In addition, the entire outer peripheral surface of the lower base portion 215a may be tapered downward.

The upper base portion 215b has a larger outer shape in plan view than the lower base portion 215 a.

The carriage base 215 is formed with a head support hole 218 penetrating the carriage base 215 in the Z direction. In each head support hole 218, the ink-jet head 5 is supported. As shown in fig. 22, the inkjet head 5 according to the present embodiment is supported by the carriage base 215 in a state where the ejection surface is located above the lower surface of the carriage base 215 (lower base 215 a). This surrounds the ink jet heads 5 with the carriage base 215, and prevents interference between the recording medium P and the ink jet heads 5.

As shown in fig. 21, the

side plates

216a and 216b are erected upward from both ends in the Y direction of the carriage base 215.

The rear plate 217 is erected upward from the other end in the X direction of the carriage base 215. The sensor portion 206 and the detection piece 210 are provided on the rear plate 217.

In the cleaning unit 230 shown in fig. 21, the unit guide 231 is a linear cam groove extending upward as going outward in the Y direction. The support pin 79 is slidably supported in the unit guide 231. That is, the cover unit 234 moves up and down in accordance with the movement in the Y direction, and moves to the open position, the carriage cover position, and the head cover position.

As shown in fig. 22, a seal member 240 is disposed at an upper end portion of the side wall portion 78a in the carriage cover 78. The sealing member 240 is disposed over the entire periphery of the side wall portion 78 a. Specifically, the sealing member 240 includes a fixing portion 241 disposed on the upper surface of the side wall portion 78a, and a lip portion 242 protruding from the fixing portion 241.

The lip portion 242 is cantilevered from the fixing portion 241 so as to face the inside of the carriage cover 78. Specifically, the lip portion 242 is inclined upward as going from the base end portion to the tip end portion. The lip portion 242 is located lower than the lower base portion 215a in the open position.

Fig. 23 is a cross-sectional view corresponding to fig. 22 showing a state where the carriage cover 78 is at the carriage cover position.

As shown in fig. 23, the lip portion 242 surrounds the periphery of the lower base portion 215a (overlaps the lower base portion 215a in the Z direction) in the carriage cover position and the hood position. In the present embodiment, the tip end portion (upper end portion) of the lip portion 242 is close to or in contact with the outer peripheral surface of the lower base portion 215a in the carriage cover position and the head cover position. Further, in the carriage cover position and the head cover position, since the carriage cover 78 is filled with a gas having a higher specific gravity than air (a gas in which ink and a cleaning liquid are evaporated), the lip portion 242 does not necessarily need to be in contact with the outer peripheral surface of the lower base portion 215 a. In addition, the inclination angle (elevation angle) of the lip portion 242 with respect to the XY plane is preferably less than 90 °.

The sealing member 240 is formed of an elastically deformable material. As such a material, rubber, a resin material, metal, or the like is preferably used. Further, at least the lip portion 242 of the seal member 240 may be elastically deformable. The sealing member 240 may be provided on at least a part of the side wall portion 78a, and need not be provided over the entire periphery of the side wall portion 78 a.

As shown in fig. 20, the printer 220 includes a cap position detection unit 250, and the cap position detection unit 250 detects the relative position of the cap unit 234 and the inkjet head 5 (carriage 201) in the Z direction. The cover position detecting member 250 is, for example, a photo interrupter sensor. The cover position detection member 250 includes a detection piece 251 provided in the cover unit 234 and a sensor portion 252 provided in the carriage 201.

The detection piece 251 protrudes from the upper end portion of the stopper wall portion 81 toward the other side in the X direction.

The sensor portion 252 is provided at the other end portion in the X direction of the side plate 216 a. The sensor unit 252 includes a light emitting unit and a light receiving unit. The detection piece 251 can pass between the light emitting portion and the light receiving portion while the cover unit 234 is being raised relative to the carriage 201. The sensor portion 252 detects, for example, an on state in which the light receiving portion receives light emitted from the light emitting portion, and an off state in which the light emitted from the light emitting portion is blocked by the detection piece 251. The control unit determines that the carriage 201 is located at the Z-direction reference position when the detection result of the sensor unit 252 is in the off state. The amount of movement in the Y direction required for the cover unit 234 to rise from the Z-direction reference position to the carriage cover position and the amount of movement in the Y direction required for the cover unit 234 to rise from the Z-direction reference position to the head cover position are stored in the control unit as the number of counts of encoder pulses.

Next, a carriage cover method and a head cover method according to the present embodiment will be described. In the following description, the description is started from the time when the carriage 201 is at the wiping standby position of the cleaning region C and the cleaning unit 230 is at the cover initial position (facing position and open position).

As shown in fig. 21, in order to move the cover unit 234 to the carriage cover position and the head cover position, the carriage 201 is moved outward in the Y direction from the wiping standby position, as in the first embodiment. Thus, the cover unit 234 moves outward in the Y direction together with the carriage 201 as the carriage 201 moves outward in the Y direction.

Fig. 24 is an operation explanatory diagram for explaining the carriage cover method.

As shown in fig. 24, in the process of moving the cover unit 234 outward in the Y direction from the open position, the support pin 79 moves upward in the unit guide 231 toward the outside in the Y direction. Thereby, the cover unit 234 moves upward as it goes outward in the Y direction. Then, the detection piece 251 of the cover unit 234 reaches the Z-direction reference position by blocking the sensor portion 252 while moving upward. When the cover unit 234 reaches the Z-direction reference position, a detection signal of the off state is output from the sensor 252 to the control unit.

Upon receiving the off-state detection signal from the sensor section 252, the control section moves the carriage 201 outward in the Y direction in accordance with a predetermined number of encoder pulses. Thus, the cover unit 234 rises by a predetermined amount with the movement of the carriage 201 outward in the Y direction, and reaches the carriage cover position.

Fig. 25 is an operation explanatory diagram for explaining a hood method.

As shown in fig. 25, when the cover unit 234 is moved to the head cover position, the carriage 201 is moved outward in the Y direction in accordance with a predetermined number of encoder pulses from the time when the sensor section 252 receives the off-state detection signal. Thus, the cover unit 234 rises by a predetermined amount with the movement of the carriage 201 outward in the Y direction, and reaches the hood position.

As described above, in the present embodiment, the cap position detection means 250 is provided, and the cap position detection means 250 detects the relative position (Z-direction reference position) of the cap unit 234 and the inkjet head 5 in the Z direction.

According to this configuration, by detecting the relative positions of the cover unit 234 and the inkjet heads 4 in the Z direction, the inkjet heads 5 can be reliably covered at the carriage cover position and the head cap position. That is, when the height of the carriage 201 (the ink jet head 5) is changed after shipment according to the type (material, thickness, etc.) of the recording medium P, the detection position by the cap position detection means 250 is shifted in the Y direction, but the Z direction reference position is kept constant. Therefore, by setting the carriage cover position and the head cover position to distances from the Z-direction reference position, the inkjet head 5 can be reliably covered regardless of the height of the inkjet head 5 at the wiping standby position. As a result, drying of the ink can be reliably suppressed.

In the present embodiment, a configuration is adopted in which a seal member 240 is provided so as to surround the periphery of the carriage base 215 at the carriage cover position and the head cap position.

According to this configuration, for example, unlike the case where the seal member and the carriage base 215 face each other in the Z direction, the seal member can be prevented from being sandwiched between the cover unit 234 and the carriage base 215 in the Z direction during the process of raising the cover unit 234. This prevents the cover unit 234 from being restricted from rising by the seal member while moving from the carriage cover position to the head cover position. As a result, the carriage base 215 and the carriage cover 78 can be sealed at each cover position, and the drying of the ink can be reliably suppressed.

Further, assuming a configuration in which the sealing member and the carriage base 215 face each other in the Z direction, since the distance between the sealing member 240 and the carriage base 215 fluctuates in the process of the cover unit 234 rising, the sealing effect fluctuates in each cover position. In addition, when the height of the carriage 201 (inkjet head 5) is changed after shipment, the sealing effect also fluctuates in the two cap positions.

In contrast, in the present embodiment, in the region where the seal member 240 and the carriage base 215 overlap in the Z direction, the distance (the distance in the X direction and the distance in the Y direction) between the tip end portion of the lip portion 242 and the outer peripheral surface of the carriage base 215 is maintained constant. As a result, a certain sealing effect can be obtained at each cover position.

When the seal member 240 comes into contact with the outer peripheral surface of the carriage base 215, the seal member 240 slides on the outer peripheral surface of the carriage base 215 when the cover unit 234 and the carriage 201 move relative to each other in the Z direction. Therefore, even if ink or the like solidifies between the seal member 240 and the carriage base 215, the seal member 240 and the carriage base 215 are easily detached.

In the present embodiment, the periphery of the carriage base 215 is surrounded by the seal member 240, and the inkjet heads 5 are surrounded together.

According to this configuration, compared with a configuration in which each ink jet head 5 is individually surrounded, the fluctuation of the air pressure when the cap is attached and detached is small. Therefore, the meniscus formed in the nozzle holes 31 and 32 can be prevented from being broken.

In the present embodiment, a chamfered portion 219 is formed on the outer peripheral edge of the lower end of the carriage base 215.

According to this configuration, when the cover unit 234 passes the lower end edge of the carriage base 215 while moving to the carriage cover position and the head cover position, the sealing member 240 can be prevented from contacting the corner of the carriage base 215. This enables smooth transition to each cover position, and also improves the durability of the seal member 240.

In the second embodiment, the case where the photo interrupter sensor is used for the cover position detection member 250 has been described, but the present invention is not limited to this configuration. For example, a micro switch, a proximity sensor, or the like may also be used.

In the above embodiment, the configuration in which both the carriage cover position and the hood position are set based on the Z-direction reference position has been described, but the present invention is not limited to this. The hood position may be set based on at least the Z-direction reference position.

(modification example)

In the above embodiment, the case where the cam groove is used for the unit guides 71 and 231 has been described, but the present invention is not limited to this configuration.

For example, as shown in fig. 26, the cover unit 66 and the unit frame 65 (see fig. 5) may be coupled to each other by a link bar 300 that can be rotated. Specifically, the first end portion of the link bar 300 is coupled to the cover unit 66 so as to be rotatable about a rotation shaft 301 extending in the X direction. The second end of the link bar 300 is coupled to the unit frame 65 so as to be rotatable about a rotation shaft 302 extending in the X direction.

According to this configuration, as shown in fig. 26 and 27, the cover unit 66 is pressed outward in the Y direction via the stopper wall 81, and the cover unit 66 moves outward in the Y direction together with the carriage 21. At this time, the cover unit 66 moves upward as going outward in the Y direction by the rotation of the link bar 300 about the

respective rotation shafts

301 and 302. Thereby, the carriage cover position and the head cover position are obtained.

In the configuration of fig. 26 and 27, a cover position detection means 250 (see fig. 20) as in the second embodiment may be mounted. In this case, the amount of movement in the Y direction to each cover position is calculated based on the amount of elevation from the Z-direction reference position to the carriage cover position, the head cover position, and the amount of elevation of the cover unit 66 corresponding to the amount of rotation of the link bar 300. This makes it possible to reliably cover the inkjet head 5 regardless of the height of the inkjet head 5, as in the second embodiment.

As shown in fig. 28, the cover unit 66 may be moved up and down by a cam 310. The cam 310 is formed in an elliptical shape, for example. The cam 310 is configured to be rotatable about a central axis (intersection of the short axis and the long axis) extending in the X direction. The outer peripheral surface of the cam 310 is configured to be able to slide on the lower surface of the cover unit 66.

According to this configuration, the cam 310 is rotated at the time when the carriage 21 reaches the wiping standby position. Then, as shown in fig. 28 and 29, the cover unit 66 gradually moves upward as the cam 310 rotates. Thereby, the carriage cover position and the head cover position are obtained. Note that, in the configuration of fig. 28 and 29, a cover position detection member 250 (see fig. 20) as in the second embodiment may be mounted. In this case, it is preferable that the amount of lift from the Z-direction reference position to the carriage cover position and the head cover position be stored in the control unit as the amount of rotation of the cam 310.

The technical scope of the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the scope of the present invention.

For example, in the above-described embodiment, the inkjet printer 1 is described as an example of the liquid ejecting apparatus, but the present invention is not limited to the printer. For example, it may also be a facsimile machine, an on-demand printer, etc.

In the above-described embodiment, the configuration in which the ink jet head (carriage) moves relative to the cleaning device has been described, but the present invention is not limited to this configuration, and may be configured such that the cleaning device moves relative to the ink jet head (carriage).

In the above embodiment, the description has been made of the inkjet head of the two-line type in which the nozzle holes 31 and 32 are arranged in two lines, but the present invention is not limited thereto. For example, an inkjet head having three or more rows of nozzle holes may be used, or an inkjet head having one row of nozzle holes may be used.

In the above embodiment, the edge-fire type ink jet head 5 is described as an example, but the invention is not limited to this configuration. That is, the ink jet head 5 may be a so-called side-shooter type that ejects ink from the center portion of the ejection channel in the channel extending direction.

In the above embodiment, the structure in which the

respective passages

43 and 44 are formed linearly in the Z direction has been described, but the present invention is not limited thereto, and may extend in a direction intersecting the Z direction.

In the above-described embodiment, the so-called off carriage (off carriage) type printer 1 in which the ink tank 13 is mounted separately from the carriage 21 (in the housing 7) has been described, but the present invention is not limited to this configuration. That is, the ink tank may be used in a so-called on carriage type (on carriage) printer in which the ink tank is mounted on the carriage 21. In the carriage exterior, the sub tank may be mounted on the carriage 21.

As in the squeegee mechanism 115 shown in fig. 30, the tip end portion of the first squeegee 121 may be divided into a portion where the

nozzle rows

56 and 57 are wiped and a portion where the nozzle guard 37 is wiped. According to this configuration, even when the ejection surface of the ink jet head 5 is uneven, the scraper mechanism 115 can be brought into uniform contact with the convex portion formed by the lower surface of the nozzle guard 37 and the concave portion formed by the lower surface of the nozzle plate 35. This makes it possible to reliably wipe the entire discharge surface.

Further, a recess 200 recessed in a direction away from the first blade 121 may be formed in a portion of the distal end portion of the second blade 122 corresponding to the

nozzle rows

56 and 57. With this configuration, ink adhering to the periphery of the

nozzle rows

56 and 57 in the discharge surface can be efficiently sucked, and therefore, a decrease in discharge performance due to ink adhering to the discharge surface can be suppressed.

In the above embodiment, the configuration in which the cap unit abuts against the discharge surface in the head cap position has been described, but in addition to this configuration, a configuration in which ink is sucked through the nozzle holes 31 and 32 is also possible.

In the above-described embodiment, the configuration surrounding the carriage at each cap position has been described, but the present invention is not limited to this configuration, and may be configured to surround each ink jet head 5.

In the above embodiment, the configuration in which the seal member 240 surrounds the carriage base 215 at both the carriage cover position and the head cover position has been described, but the present invention is not limited to this configuration. For example, the seal member 240 may surround the carriage base 215 at least at the head cover position.

In addition, the components in the above embodiments may be replaced with known components as appropriate without departing from the scope of the present invention, and the above modifications may be combined as appropriate.

Description of the symbols

1 ink jet printer (liquid jet device)

5 ink-jet head (liquid-jet head)

6 cleaning device

31 first nozzle hole (injection hole)

32 second nozzle hole (injection hole)

66 cover unit

67 scraper unit

75 head cover mechanism

81 stop wall part (engaging part)

219 chamfered edge

240 sealing member

Claims

1. A cleaning device for a liquid ejection head, comprising a cap unit movable in a direction normal to an ejection surface on which ejection holes open in the liquid ejection head to cap the ejection surface,

the cover unit is configured to be movable between:

an open position to open the injection hole,

a first cover position covering the injection hole in a state of being close to the injection surface in the normal direction, an

A second cover position for closing the injection hole in a state of abutting on the injection surface in the normal direction,

the cap unit includes an elastically deformable sealing member that surrounds the periphery of the liquid ejecting head in the first cap position to perform a predetermined seal.

2. The cleaning device of a liquid ejection head according to claim 1,

the liquid ejecting apparatus includes a detection member that detects a relative position between the cap unit and the liquid ejecting head in the normal direction.

3. The cleaning device for a liquid ejection head according to claim 1 or claim 2,

the seal member surrounds the periphery of the liquid ejection head in the second cap position.

4. The cleaning device for a liquid ejection head according to claim 3,

a plurality of the liquid ejecting heads are mounted on a carriage,

the seal member surrounds the carriage at the first cap position and the second cap position, and surrounds the plurality of liquid ejecting heads together.

5. The cleaning device for a liquid ejection head according to claim 1 or claim 2,

the cap unit includes a cap cover mechanism that abuts against the ejection surface of the liquid ejecting head in the second cap position,

the cleaning solution is impregnated in the head cap mechanism.

6. The cleaning device for a liquid ejection head according to claim 1 or claim 2,

the cap unit includes an engaging portion that engages with the liquid ejecting head in a main scanning direction among tangential directions of the ejection surface,

the cap unit is movable in the normal direction in accordance with movement of the liquid ejecting head in the main scanning direction in a state where the liquid ejecting head is engaged with the engagement portion.

7. The cleaning device for a liquid ejection head according to claim 1 or claim 2,

a blade unit arranged in the cap unit in a sub-scanning direction intersecting a main scanning direction of the liquid ejecting head among tangential directions of the ejection surface to wipe the ejection surface,

the squeegee unit and the cover unit are integrally movable in the sub-scanning direction.

8. The cleaning device for a liquid ejection head according to claim 7,

the squeegee unit is movable between: a wiping position capable of abutting on the ejection surface in the normal direction, and a spacing position spaced from the ejection surface in the normal direction.

9. A liquid ejecting apparatus is provided with:

liquid ejecting head and

the cleaning device according to claim 1 or claim 2.

10. A liquid ejecting apparatus is provided with:

the cleaning device according to claim 4, wherein the cleaning member,

a liquid ejection head having ejection holes for ejecting liquid, and

a carriage on which the plurality of liquid ejecting heads are mounted,

the carriage is configured to be movable relative to the cleaning device to a position facing the cleaning device in a normal direction of an ejection surface of the ejection orifice opening in the liquid ejection head,

a chamfered edge is formed on an outer peripheral edge of an end portion of the carriage located on the cleaning device side in the normal direction in the facing position.