LIQUID CONTAINER AND LIQUID EJECTION DEVICE

Abstract

To provide a liquid storage body and a liquid discharge device, which require no liquid storage body for storing liquid for humidification separately from the liquid storage body for storing waste liquid.SOLUTION: A waste box 110 is detachably installed on an installation part having: a waste liquid lead-out part being one example of a discharge part that discharges waste liquid; and a liquid introduction part. The waste box 110 comprises: a waste liquid introduction part 115 to be connected to the waste liquid lead-out part when installed on the installation part; and a waste storage part 86 capable of storing waste liquid discharged from the waste lead-out part. The waste box 110 also comprises: a liquid lead-out part 116 to be connected to the liquid introduction part when the waste box 110 is installed on the installation part; and an adjusted water storage part 66a (e.g., an adjusted water pack 68) that stores adjusted water being one example of liquid that is led out to the liquid introduction part. The adjusted water is liquid containing water for humidifying a cap being one example of a part to be humidified.SELECTED DRAWING: Figure 13

Description

[Technical field]

[0001] The present invention relates to a liquid container that contains liquid and a liquid ejection device. [Background technology]

[0002] A liquid ejection device, which is an example of a liquid ejection device described in Patent Document 1, includes a recording head (an example of a liquid ejection section) having a plurality of nozzles that eject recording liquid to be applied to a target for recording, and a cap that faces the nozzles while in contact with the recording head and can receive recording liquid (waste liquid). The cap has a recording liquid receiving section that can receive the recording liquid ejected from the nozzles, and a moisturizing liquid receiving section that can receive moisturizing liquid. The liquid ejection device includes a waste liquid tank (liquid container) that stores waste liquid sucked from the cap by a pump, and a moisturizing cartridge that supplies moisturizing liquid to the moisturizing liquid receiving section by a pump. The recording liquid ejected from the nozzles to the cap is stored in the waste liquid tank as waste liquid.

[0003] Even if the moisture content decreases due to evaporation or the like when the cap is kept in contact with the recording head for a long period of time, the moisture content can be supplied from the moisture cartridge, so that the recording head can be kept moist for a long period of time. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2012-61785 A Summary of the Invention [Problem to be solved by the invention]

[0005] However, in the liquid ejection device described in Patent Document 1, it is necessary to newly provide a liquid storage unit such as a moisturizing cartridge for moisturizing the nozzles. This increases the number of cartridges to be replaced in addition to the ink cartridges, which increases the effort required for users to replace storage units such as cartridges, resulting in a problem that the usability of the liquid ejection device becomes poor. [Means for solving the problem]

[0006] A liquid container that solves the above problem is a liquid container that is removably attached to an attachment part having a discharge part for discharging waste liquid and a liquid introduction part, and includes a waste liquid introduction part that is connected to the discharge part when the liquid container is attached to the attachment part, a waste liquid storage part that can store waste liquid discharged from the discharge part, a liquid discharge part that is connected to the liquid introduction part when the liquid container is attached to the attachment part, and a liquid storage part that stores liquid that is discharged to the liquid introduction part, wherein the liquid is a liquid containing water for humidifying the part to be humidified.

[0007] A liquid ejection device that solves the above problem includes a liquid ejection unit that ejects liquid supplied from a liquid supply source from a nozzle, a cap as the humidified part that can contact the liquid ejection unit to form a closed space in which the nozzle opens, the attachment unit to which the liquid container is detachably attached, a supply flow path that communicates with the liquid introduction unit and the cap, and a first liquid delivery unit that delivers the liquid in the liquid container to the cap. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a perspective view showing a liquid ejection device according to an embodiment. [Diagram 2] FIG. 2 is a schematic diagram showing the arrangement of components around a liquid ejection head. [Diagram 3] 3 is a schematic front view of the components as viewed from the discharge direction in FIG. 2. [Figure 4] FIG. [Diagram 5] FIG. 2 is a schematic diagram showing a configuration of a capping device. [Figure 6] FIG. 4 is a perspective view showing the mounting portion and the waste liquid box. [Figure 7] FIG. 4 is a perspective view of the waste liquid box seen obliquely from above. [Figure 8] FIG. [Figure 9] FIG. [Figure 10] FIG. [Figure 11] FIG. 4 is a perspective view showing the waste liquid box with the first cover removed. [Figure 12] FIG. 4 is a perspective view showing the waste liquid box with the second cover removed. [Figure 13] FIG. 4 is an exploded perspective view of the waste liquid box seen obliquely from above. [Figure 14] FIG. 4 is an exploded perspective view of the waste liquid box as viewed obliquely from below. [Figure 15] 15 is a cross-sectional view taken along line 15-15 in FIG. [Figure 16] FIG. 2 is a block diagram showing an electrical configuration of the liquid ejection device. [Figure 17] 11 is a flowchart showing a circulation operation. [Figure 18] 5 is a flowchart showing a density adjustment operation. [Figure 19] 5A and 5B are schematic diagrams showing the state of the humidification fluid when the circulation operation and the concentration adjustment operation are performed. [Figure 20] FIG. 11 is a schematic diagram showing the arrangement of components around a liquid ejection head in a modified example. [Figure 21] 5A and 5B are schematic diagrams showing the state of the humidification fluid when the circulation operation and the concentration adjustment operation are performed. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, an embodiment of a liquid ejection device, a capping device used in the liquid ejection device, and a maintenance method for the capping device used in the liquid ejection device will be described with reference to the drawings. The liquid ejection device is, for example, an inkjet printer that ejects ink, which is an example of a liquid, onto a medium such as paper to record (print).

[0010] In the drawings, the liquid ejection device 11 is placed on a plane, and the width direction and depth direction are substantially horizontal. The vertical direction is indicated as the Z axis, and the directions along the plane intersecting the Z axis are indicated as the X axis and the Y axis. The X axis, the Y axis, and the Z axis are preferably perpendicular to each other. In the following description, the X axis direction is also referred to as the width direction X, the Y axis direction as the depth direction Y, and the Z axis direction as the vertical direction Z.

[0011] <Configuration of the liquid ejection device> 1, the liquid ejection device 11 includes a rectangular parallelepiped main body 12, and an image reading unit 13 and an automatic feed unit 14 attached to the upper portion of the main body 12. The liquid ejection device 11 has a configuration in which the main body 12, the image reading unit 13, and the automatic feed unit 14 are stacked in this order from the bottom in the vertical direction Z.

[0012] The image reading unit 13 is configured to be able to read images such as characters and photographs recorded on a document. The automatic feeding unit 14 is configured to be able to feed a document toward the image reading unit 13. The image reading unit 13 also has an operation unit 15 that is operated when giving instructions to the liquid ejection device 11. The operation unit 15 has a display unit 15a consisting of, for example, a touch panel type screen, operation buttons, and the like.

[0013] The main body 12 has a plurality of medium storage sections 16 capable of storing media such as paper. In this embodiment, the main body 12 has a total of four medium storage sections 16. The medium storage sections 16 are configured to be removable from the main body 12. The main body 12 also has a recording section 20 that records on the medium M within the main body 12. The recording section 20 is equipped with a head unit 24 having a liquid ejection head 21 capable of ejecting liquid. Furthermore, the main body 12 has a mounting section 17 on its upper portion on which the medium M on which recording has been performed is placed. The mounting section 17 has a mounting surface 17a on which the medium M is placed. It is to be noted that the number of medium storage sections 16 may be only one.

[0014] The medium M contained in the medium containing section 16 is transported along a transport path 19 from the medium containing section 16 through the recording section 20 to the mounting section 17. A feed roller (not shown) rotates in contact with the uppermost medium M among the multiple media M contained in the medium containing section 16, thereby sending the uppermost medium M from the medium containing section 16 to the recording section 20 located above the medium containing section 16. As the medium M passes through the recording section 20, the liquid ejection head 21 ejects liquid toward the medium M, and the ejected liquid adheres to the medium M to perform recording. After recording, the medium M is ejected toward the mounting section 17 by a pair of ejection rollers (not shown).

[0015] 2, a cap unit 51 and a wiper carriage 41 provided in a capping device described later are arranged around the liquid ejection head 21 provided in the recording unit 20 on the opposite side to the side where the head unit 24 is located with respect to the transport path 19. The head unit 24 includes the liquid ejection head 21 and a support unit 25 that holds the liquid ejection head 21.

[0016] The liquid ejection head 21 is configured to eject liquid from a plurality of nozzles 22 constituting a plurality of nozzle groups, while extending in the width direction X, onto the medium M. The direction in which the liquid is ejected when the liquid ejection head 21 ejects the liquid onto the medium M is referred to as an ejection direction Y1. In addition, the direction in which the medium M is transported when the liquid ejection head 21 ejects the liquid onto the medium M is referred to as a first transport direction Z1.

[0017] In this embodiment, the nozzle surface 23 on which the nozzles 22 are arranged is not horizontal, but has a first predetermined angle θ1 with respect to the horizontal. That is, in this embodiment, the liquid ejection head 21 is arranged in a state in which the nozzle surface 23 has the first predetermined angle θ1 with respect to the horizontal, and in this state, the liquid ejection head 21 ejects liquid onto the medium M. Note that the nozzle surface 23 on which the nozzles 22 are arranged may also be arranged horizontally. That is, the liquid ejection head 21 may be arranged in a state in which the nozzle surface 23 is horizontal.

[0018] The liquid ejection head 21 of this embodiment is a line head having a number of nozzles 22 capable of simultaneously ejecting liquid across the entire width of the medium M in a width direction X intersecting with the first transport direction Z1 and the ejection direction Y1. The liquid ejection device 11 performs line printing by ejecting liquid from the multiple nozzles 22 located at positions facing the entire width of the medium M, which is transported at a constant speed.

[0019] In the liquid ejection device 11, maintenance operations such as capping, cleaning, flushing, wiping, etc. are performed to prevent or resolve ejection failures caused by clogging of the nozzles 22 of the liquid ejection head 21 or adhesion of foreign matter.

[0020] Capping refers to an operation in which the cap unit 51 comes into contact with the nozzle surface 23 of the liquid ejection head 21 so as to surround the nozzles 22 when the liquid ejection head 21 is not ejecting liquid. Capping suppresses thickening of the liquid inside the nozzles 22, thereby preventing ejection defects.

[0021] Cleaning refers to an operation of applying pressure to the upstream side of the liquid ejection head 21 to forcibly expel liquid from the nozzles 22 , or applying a suction force to the nozzles 22 of the liquid ejection head 21 to forcibly expel liquid from the nozzles 22 .

[0022] Flushing refers to a discharge operation for discharging droplets unrelated to printing from the nozzles 22. Flushing is also called idling. Flushing discharges thickened ink, air bubbles, or foreign matter that may cause discharge defects from the nozzles 22, thereby preventing clogging of the nozzles 22. Of the liquid discharged from the liquid discharge head 21, liquid that is not used for printing is called waste liquid. The liquid discharged by flushing is waste liquid because it is not used for printing. The waste liquid discharged by flushing is received by the cap unit 51. That is, flushing is performed by the liquid discharge head 21 discharging droplets from the nozzles 22 into the cap unit 51.

[0023] Wiping refers to the operation of wiping the nozzle surface 23 with a rubber wiper, a cloth wiper, or the like. Wiping removes liquid and dirt such as dust adhering to the nozzle surface 23 of the liquid ejection head 21. Note that the liquid wiped off by wiping is also waste liquid, as it is not used for printing.

[0024] The position of the head unit 24 when the liquid ejection head 21 ejects liquid onto the medium M, i.e., when the liquid ejection head 21 records on the medium M, is referred to as the recording position. The position of the cap unit 51 when the liquid ejection head 21 ejects liquid onto the medium M is referred to as the retracted position. The position of the head unit 24 when the liquid ejection device 11 performs a maintenance operation is referred to as the maintenance position. The position of the cap unit 51 when the liquid ejection device 11 performs a maintenance operation is also referred to as the maintenance position.

[0025] As shown in Fig. 2, the head unit 24 is moved by a head moving mechanism (not shown) between a recording position indicated by a solid line in Fig. 2 and a maintenance position indicated by a two-dot chain line in Fig. 2. The direction in which the head unit 24 moves from the recording position to the maintenance position is called a first direction D1. The direction in which the head unit 24 moves from the maintenance position to the recording position is called a second direction D2.

[0026] The cap unit 51 is moved between a retracted position shown by a solid line in FIG. 2 and a maintenance position shown by a two-dot chain line in FIG. 2 by a cap moving mechanism (not shown). The direction in which the cap unit 51 moves from the recording position to the maintenance position is called a third direction D3. The direction in which the cap unit 51 moves from the maintenance position to the recording position is called a fourth direction D4. The cap unit 51 has a recess 57 that receives liquid such as ink discharged for maintenance from the nozzle 22 of the liquid ejection head 21 as waste liquid L2. The recess 57 contains an absorber 53 that absorbs the waste liquid L2. The cap unit 51 of this embodiment also has a humidification chamber 55 that supplies humidification fluid L1a into the recess 57, and a first moisture permeable membrane 54 that covers one surface of the opening of the humidification chamber 55. The humidification fluid L1a that permeates the first moisture permeable membrane 54 from the humidification chamber 55 moisturizes the nozzle 22 of the liquid ejection head 21 during capping. The detailed configurations of the first moisture permeable membrane 54 and the humidification chamber 55, and a supply system that supplies the humidification fluid L1a to the humidification chamber 55 will be described later.

[0027] As shown in Fig. 2, the cap unit 51 moves in the third direction D3 from the retracted position shown by the solid line in Fig. 2 and is positioned at the maintenance position shown by the two-dot chain line in Fig. 2, and then the head unit 24 moves in the first direction D1 from the recording position shown by the solid line in Fig. 2 and is positioned at the maintenance position shown by the two-dot chain line in Fig. 2. As a result, the head unit 24 is capped by the cap unit 51. In this embodiment, in this capped state, the liquid ejection head 21 ejects liquid droplets from the nozzles 22 toward the inside of the cap unit 51, thereby performing flushing. That is, in the liquid ejection device 11 of this embodiment, both capping and flushing are performed at the maintenance position. Flushing may be performed in a state in which the liquid ejection head 21 is separated from the cap unit 51.

[0028] When maintenance is completed, the head unit 24 moves in the second direction D2 from the maintenance position shown by the two-dot chain line in Fig. 2 to a recording position shown by the solid line in Fig. 2. After that, the cap unit 51 moves in the fourth direction D4 from the maintenance position shown by the two-dot chain line in Fig. 2 to a retracted position shown by the solid line in Fig. 2. At this time, the wiper carriage 41 is positioned so as not to overlap the head unit 24 and the cap unit 51 in the width direction X. The movement of the wiper carriage 41 will be described later.

[0029] <Configuration of liquid ejection head and cap unit> As shown in FIG. 3, the liquid ejection head 21 includes a plurality of unit ejection heads 21a. The plurality of unit ejection heads 21a are arranged at a first predetermined pitch P1 in the width direction X on the surface of the support portion 25 facing the transport path 19 shown in FIG. 2. The unit ejection heads 21a are composed of a plurality of nozzle rows 21b. The plurality of unit ejection heads 21a are arranged in a state inclined by a second predetermined angle θ2 with respect to a first transport direction Z1 in which the medium M is transported. In other words, the nozzle rows 21b are also arranged in a state inclined by the second predetermined angle θ2 with respect to the first transport direction Z1. In this embodiment, the liquid ejection head 21 includes five unit ejection heads 21a, and each unit ejection head 21a is composed of six nozzle rows 21b.

[0030] In this embodiment, the cap unit 51 has a plurality of caps 51a and a holding portion 59 that holds the plurality of caps 51a. The caps 51a are objects to be humidified and correspond to an example of a humidified portion. On the opposite side of the conveying path 19 shown in FIG. 2 to the side where the head unit 24 is located, the plurality of unit caps 51a are arranged at a first predetermined pitch P1 in the width direction X. The plurality of unit caps 51a are arranged in a state inclined by a second predetermined angle θ2 with respect to the first conveying direction Z1 in which the medium M is conveyed. That is, the unit caps 51a have a shape of a substantially parallelogram when viewed from a direction along the ejection direction Y1. In this embodiment, the cap unit 51 has five unit caps 51a.

[0031] One unit cap 51a is disposed at a position facing each unit discharge head 21a. Therefore, when the head unit 24 is capped by the cap unit 51, each of the unit discharge heads 21a is covered by a separate unit cap 51a. That is, the nozzles 22 of the liquid discharge head 21 are covered for each unit discharge head 21a by the same number of unit caps 51a as the unit discharge heads 21a. In this embodiment, the nozzles 22 of the liquid discharge head 21 composed of five unit discharge heads 21a are covered for each unit discharge head 21a by the five unit caps 51a of the cap unit 51. As a result, during capping, all of the nozzles 22 of the liquid discharge head 21 are covered by the cap unit 51. The unit cap 51a includes a case 56 having an opening that opens toward the first transport direction Z1. An annular seal portion 56c is fixed to the open end of the case 56. The case 56 contains a lattice-shaped regulating member 52 and, further inside, an absorber 53 capable of absorbing waste liquid while its position is regulated by the regulating member 52. In the following, the unit cap 51a will also be referred to simply as "cap 51a."

[0032] During non-recording and maintenance, the head unit 24 shown in Fig. 3 is moved from the recording position shown by the solid line in Fig. 2 to the maintenance position shown in Fig. 3 (position shown by the two-dot chain line in Fig. 2) by a head moving mechanism (not shown). Next, the cap unit 51 shown in Fig. 3 moves from the retracted position shown in the same figure in a third direction D3, and is disposed at the maintenance position shown by the two-dot chain line in Fig. 2 (see also Fig. 4). As a result, the liquid ejection head 21 is capped by the cap 51a. For example, after maintenance is completed, the cap unit 51 moves from the maintenance position in a fourth direction D4, thereby returning to the retracted position shown in Fig. 3.

[0033] The wiper carriage 41 shown in Fig. 3 is reciprocated by a wiper movement mechanism (not shown) between a retracted position shown by a solid line in Fig. 3 and a return position shown by a two-dot chain line in Fig. 3. After the head unit 24 moves in a first direction D1 from the recording position shown in Fig. 2 and is positioned at a maintenance position shown by a two-dot chain line in Fig. 2, the wiper carriage 41 moves from the retracted position shown by a solid line in Fig. 3 in a fifth direction D5 to the return position shown by a two-dot chain line in Fig. 3. As a result, the nozzle surface 23 of the head unit 24 is wiped by the wiper member 42 of the wiper carriage 41.

[0034] When wiping is completed, the head unit 24 moves in the second direction D2 from the maintenance position shown by the two-dot chain line in Fig. 2, and is located at the recording position shown by the solid line in Fig. 2. Thereafter, the wiper carriage 41 moves in the sixth direction D6 from the turning back position shown by the two-dot chain line in Fig. 3, and returns to the retracted position shown in Fig. 3.

[0035] <About the cap composition> Next, the configuration of the cap 51a will be described with reference to FIG. 4, the liquid ejection device 11 includes a capping device 50. The capping device 50 includes a cap 51a that is in contact with the liquid ejection head 21 and is capable of forming a closed space SP in which the nozzles 22 are open.

[0036] As shown in FIG. 4, the cap 51a has a restricting member 52, an absorber 53, a first moisture permeable membrane 54, a humidification chamber 55, and a case 56. The cap 51a has a low rectangular column shape with a substantially parallelogram-shaped bottom surface. In this embodiment, the cap 51a is used with the substantially parallelogram-shaped bottom surface disposed on the XZ1 plane shown in FIG. 2. That is, the cap 51a shown in FIG. 5 is used with the substantially parallelogram-shaped bottom surface inclined with respect to the horizontal. The XZ1 plane is a plane parallel to the nozzle surface 23 of the liquid ejection head 21 shown in FIG. 2.

[0037] 4, the restricting member 52 is a lattice- or mesh-like member for restricting the position of the -Y1 direction side of the absorber 53. The restricting member 52 is made of a thin metal plate such as stainless steel. Thus, the cap 51a is configured to allow liquid to pass from the -Y1 direction side of the restricting member 52 to the +Y1 direction side and from the +Y1 direction side to the -Y1 direction side within the cap 51a.

[0038] 4, the absorbent body 53 is formed in a thin plate shape of a substantially parallelogram extending in the XZ1 plane. The absorbent body 53 is configured to be capable of absorbing liquid. Therefore, the absorbent body 53 may be displaced so as to increase in volume, that is, swell, by absorbing liquid.

[0039] The regulating member 52 widely exposes the surface 53a of the absorbent 53 while regulating the absorbent 53 at a predetermined position in order to keep constant the distance between the surface 53a and the nozzle surface 23 shown in Fig. 4. In other words, the regulating member 52 suppresses the absorbent 53 from being displaced in the -Y1 direction when the absorbent 53 swells.

[0040] As shown in FIG. 4, the first moisture permeable membrane 54 is formed in a sheet shape of a substantially parallelogram extending in the XZ1 plane. The first moisture permeable membrane 54 has gas permeability. That is, the first moisture permeable membrane 54 allows the passage of gas but restricts the passage of liquid. In this embodiment, the material used for the first moisture permeable membrane 54 is a material in which a fluororesin is coated on a fabric. The material used for the first moisture permeable membrane 54 may be any material that does not allow liquid to pass through but allows gas to pass through, and may be a film membrane or an elastomer membrane.

[0041] By slightly cutting out the central portions of at least three of the four sides of the first moisture permeable membrane 54 toward the inside, a communicating portion 54a is formed at the peripheral portion of the recess 57 through which liquid can pass from the -Y1 direction side to the +Y1 direction side and from the +Y1 direction side to the -Y1 direction side.

[0042] As described above, in this embodiment, the cap 51a shown in Fig. 4 is provided on the XZ1 plane inclined with respect to the horizontal, with the bottom surface of the approximate parallelogram being of the same shape. Since gravity exerts a force that causes the liquid to flow vertically in the -Z direction, the liquid is unlikely to flow to the side of the approximate parallelogram that is closest to the +Z direction. Therefore, the first moisture permeable membrane 54 may be configured not to have the communication portion 54a on the side that is closest to the +Z direction.

[0043] 4, the case 56 has an atmosphere communication hole 56a at the portion furthest on the +Z direction side, which allows communication between the space inside the case 56 and the atmosphere through the atmosphere communication hole 56a.

[0044] 4, the humidifying chamber 55 has two pipes 55c protruding from the surface on the +Y1 and +Z directions, with inlet 55a and outlet 55b opening at their tips. A rib 55e extends along a predetermined path within the humidifying chamber 55, forming a groove 55d communicating with the inlet 55a and outlet 55b. A flow path 55f is formed along a predetermined path within the humidifying chamber 55, partitioned by the rib 55e and the first moisture permeable membrane 54.

[0045] The case 56 has an atmosphere communication hole 56a, a discharge hole 56b which is an example of a hole, and a seal portion 56c. The atmosphere communication hole 56a and the discharge hole 56b communicate with the +Y1 side and the -Y1 side of the bottom surface of the approximate parallelogram.

[0046] The seal portion 56c is formed in a frame shape along the peripheral wall on the surface of the peripheral wall that forms the case 56 closest to the -Y1 direction. The material used for the seal portion 56c is, for example, a flexible material such as a rubber material or an elastomer. In order to prevent the liquid in the cap 51a from dripping from the seal portion 56c to the outside of the cap 51a, the material for the seal portion 56c may be a water-repellent elastomer material that repels the liquid ejected from the liquid ejection head 21.

[0047] The case 56 forms the outer shape of a low prism having a substantially parallelogram-shaped base of the cap 51a, and houses the restricting member 52, the absorber 53, the first moisture permeable membrane 54, and the humidification chamber 55.

[0048] The humidification chamber 55 shown in Fig. 4 has a groove 55d formed in a maze shape from the inlet 55a to the outlet 55b, which is meandering and covers the entire surface of the chamber. The surface of the opening side of the humidification chamber 55 and the first moisture permeable membrane 54 are sealed over the entire area from the inlet 55a to the outlet 55b. Therefore, the groove 55d and the first moisture permeable membrane 54 form a one-way winding flow path having a complex meandering route, and the inlet 55a and the outlet 55b are connected to each other. That is, the humidification chamber 55 is formed in a flow path that connects the inlet 55a and the outlet 55b, with a part of the wall surface of the chamber through which the humidification fluid described later flows being covered by the first moisture permeable membrane 54.

[0049] As described later, since the closed space SP in the cap 51a is humidified by the humidifying fluid flowing through the groove 55d, it is preferable that the area occupied by the groove 55d in the cap 51a in the XZ1 plane is large. That is, in order to increase the area occupied by the groove 55d with respect to the bottom surface of the cap 51a, it is preferable to lay out the flow path over the entire bottom surface of the cap 51a.

[0050] <Cap unit configuration> As shown in Fig. 4, the liquid ejection device 11 includes a capping device 50. The capping device 50 has a movable capping unit 51 shown in Fig. 3. The capping unit 51 has a cap 51a.

[0051] When the cap unit 51 moves in the first direction D1 to the maintenance position shown in Fig. 4 and then the head unit 24 moves in the third direction D3 to the maintenance position shown in Fig. 4, the cap 51a of the cap device 50 comes into contact with the nozzle surface 23 of the liquid ejection head 21. When the cap device 50 comes into contact with the liquid ejection head 21, the nozzle surface 23 and the seal portion 56c come into close contact with each other, and the nozzle surface 23 is sealed by the seal portion 56c. In other words, the cap device 50 is configured to be capable of forming a closed space SP surrounding the opening 22a of the nozzle 22 when the cap 51a, which is an example of a cap, comes into contact with the liquid ejection head 21 having the nozzle 22 that ejects liquid.

[0052] The cap 51a has a recess 57 that forms a closed space SP. In this embodiment, as shown in FIG. 4, the recess 57 is composed of the inner surface of the case 56, the outer surface of the humidification chamber 55, and the surface of the first moisture permeable membrane 54 on the absorber 53 side. The recess 57 has the absorber 53 capable of absorbing liquid at a position in contact with the first moisture permeable membrane 54, which is an example of a partition wall. The first moisture permeable membrane 54, which has gas permeability, separates the recess 57 from the humidification chamber 55. As a result, when the cap device 50 and the liquid ejection head 21 come into contact with each other, the recess 57 forms a closed space SP surrounding the opening 22a of the nozzle 22.

[0053] The regulating member 52 and the absorbent body 53 are liquid permeable. The first moisture permeable membrane 54 is not liquid permeable. Therefore, during flushing, the liquid discharged from the nozzle 22 passes through the regulating member 52 and the absorbent body 53 from the -Y1 direction side to the +Y1 direction side, but does not pass through the first moisture permeable membrane 54 from the -Y1 direction side to the +Y1 direction side.

[0054] Even when absorber 53 approaches a state where it cannot absorb any more liquid, first moisture permeable membrane 54 has no liquid permeability, so liquid does not flow into humidification chamber 55. Then, the liquid passes through communication portion 54a by gravity and is discharged from discharge hole 56b of case 56 to the outside of cap 51a.

[0055] The humidification chamber 55 has an inlet 55a through which a humidification fluid described later flows in to humidify the closed space SP, and an outlet 55b through which the humidification fluid flows out. Since the first moisture permeable membrane 54 does not have liquid permeability, the first moisture permeable membrane 54 restricts the passage of liquid in the humidification chamber 55 from the +Y1 direction side to the -Y1 direction side. As a result, in the humidification chamber 55, the liquid that flows in from the inlet 55a flows out from the outlet 55b. The humidification chamber 55 is provided in an inclined position with respect to the horizontal. The inlet 55a and the outlet 55b are provided above the center of the humidification chamber 55 in the vertical direction Z. In this embodiment, the inlet 55a and the outlet 55b are located on the +Z direction side of the center of the humidification chamber 55 in the vertical direction Z. By providing inlet 55a and outlet 55b on the +Z direction side of humidification chamber 55, it is possible to prevent liquid in humidification chamber 55 from flowing out of humidification chamber 55 from inlet 55a or outlet 55b due to head pressure.

[0056] 4, the restricting member 52, the absorber 53, and the first moisture permeable membrane 54 are gas permeable. Therefore, the air and water vapor, which are gases, pass through the restricting member 52, the absorber 53, and the first moisture permeable membrane 54 from the -Y1 direction side to the +Y1 direction side, and from the +Y1 direction side to the -Y1 direction side. As a result, the cap device 50 is configured to allow water vapor evaporated from the humidifying fluid described later to flow from the humidifying chamber 55 to the recess 57 within the cap 51a.

[0057] The recess 57 has an atmosphere communication hole 56a for communicating the closed space SP with the atmosphere. The atmosphere communication hole 56a is provided above the center in the vertical direction of the cap 51a. In this embodiment, the atmosphere communication hole 56a is provided on the +Z direction side of the center in the vertical direction Z of the recess 57. By providing the atmosphere communication hole 56a above the center in the vertical direction of the cap 51a, it is possible to prevent the atmosphere communication hole 56a from being blocked by liquid. In addition, the atmosphere communication hole 56a may be provided at a position higher than the first moisture permeable film 54, i.e., on the +Z direction side of the first moisture permeable film 54.

[0058] <Liquid supply mechanism> 5, the liquid ejection device 11 includes a liquid supply mechanism 30. The liquid supply mechanism 30 includes a liquid supply source 31 that contains liquid such as ink, a sub-tank 32, and a pump 33. The liquid supply source 31 and the sub-tank 32 are connected via a liquid supply path 34. The sub-tank 32 is connected to the liquid ejection head 21 via a supply flow path 35 and a recovery flow path 36.

[0059] 5, the liquid ejection device 11 includes a liquid supply mechanism 30 including a liquid supply source 31 that contains liquid to be supplied to the liquid ejection head 21, a sub-tank 32 that temporarily stores the liquid from the liquid supply source 31, and a pump 33 that sends the liquid to the liquid ejection head 21. The liquid ejection device 11 includes a liquid ejection head 21 as an example of a liquid ejection section that ejects the liquid supplied from the liquid supply source 31 from a nozzle 22.

[0060] The pump 33 applies pressure inside the subtank 32 to supply liquid from the subtank 32 to the liquid ejection head 21 through the supply flow path 35. Liquid that is supplied to the liquid ejection head 21 and not consumed is recovered into the subtank 32 through the recovery flow path 36. In this way, the liquid supply mechanism 30 is configured such that, by driving the pump 33, the liquid circulates through a circulation path that passes through the subtank 32, the supply flow path 35, the liquid ejection head 21, and the recovery flow path 36.

[0061] It is also possible to adopt a configuration in which there is no recovery flow path 36, and liquid is supplied from the liquid supply source 31 to the liquid ejection head 21 through the supply flow path 35. It is also possible to adopt a configuration in which liquid is supplied from the liquid supply source 31 to the liquid ejection head 21 through the supply flow path 35 by utilizing a head difference. Furthermore, it is also possible to adopt a configuration in which the liquid supply source 31 is detachably attached to an attachment portion of the head unit 24. It is also possible for the liquid supply source 31 to be configured by a cartridge such as an ink cartridge, a tank such as an ink tank, or a liquid pack such as an ink pack.

[0062] <Configuration of humidified fluid circulation mechanism> As shown in FIG. 5, the capping device 50 includes a capping unit 51 having a cap 51a, a cap moving mechanism (not shown), a humidified fluid circulating mechanism 60, and a waste liquid collecting mechanism 80.

[0063] The cap device 50 includes a humidified fluid circulation mechanism 60 having a humidified fluid storage unit 61 that stores a humidified fluid L1a, a supply flow path 62a, and a recovery flow path 62b. The supply flow path 62a communicates the humidified fluid storage unit 61 with the inlet 55a. That is, the supply flow path 62a communicates the humidified fluid storage unit 61 with a cap 51a, which is an example of a cap. The recovery flow path 62b communicates the outlet 55b with the humidified fluid storage unit 61. That is, the recovery flow path 62b communicates the cap 51a, which is an example of a cap, with the humidified fluid storage unit 61. The humidified fluid circulation mechanism 60 includes a circulation path 62 including the humidified fluid storage unit 61, the supply flow path 62a, and the recovery flow path 62b.

[0064] The humidification fluid storage section 61 has an inlet 61f and an outlet 61g. The inlet 61f of the humidification fluid storage section 61 communicates with the recovery passage 62b. The outlet 61g of the humidification fluid storage section 61 communicates with the supply passage 62a.

[0065] In the humidified fluid circulation mechanism 60, the humidified fluid L1a flowing in the circulation path 62 is a fluid containing water for humidifying the closed space SP shown in FIG. 4. The moisturizing power of the humidified fluid L1a is preferably equal to the moisturizing power of the liquid discharged from the liquid discharge head 21. The moisturizing power is the concentration of the moisturizing agent contained in the humidified fluid L1a or the liquid discharged from the liquid discharge head 21. For example, when the liquid discharge head 21 discharges ink, which is an example of a liquid, onto a medium such as paper to print, it is preferable that the moisturizing power of the humidified fluid L1a is equal to the moisturizing power of fresh ink. In addition, it is preferable that the moisturizing power of the ink is balanced for each color. The details of the humidified fluid L1a will be described later.

[0066] As shown in FIG. 3, the cap unit 51 included in the cap device 50 of this embodiment has five caps 51a. That is, the cap device 50 is configured with a plurality of caps 51a, which are an example of a cap, arranged side by side. Each of the five caps 51a has an inlet 55a shown in FIG. 4 and an outlet 55b shown in FIG. 4. Therefore, in this embodiment, the outlet 55b of one cap 51a among the plurality of caps 51a is connected to the inlet 55a of another cap 51a adjacent to the cap 51a. For example, the outlet 55b of one cap 51a and the inlet 55a of the other cap 51a adjacent to the cap 51a are connected by a tube not shown, and the outlet 55b and the inlet 55a are connected to each other. As a result, the inlet 55a located at the most upstream position and the outlet 55b located at the most downstream position are connected to each other. The inlet 55a located at the most upstream position is connected to the supply flow path 62a shown in FIG. 5. The outlet 55b located most downstream is connected to the recovery passageway 62b shown in Fig. 5. That is, the capping device 50 of the present embodiment is configured so that the humidification fluid L1a flowing in the circulation path 62 shown in Fig. 5 can flow through the grooves 55d of the humidification chambers 55 shown in Fig. 4 of all of the caps 51a. When the capping device 50 has only one cap 51a, the inlet 55a of that cap 51a may be connected to the supply passageway 62a, and the outlet 55b of that cap 51a may be connected to the recovery passageway 62b.

[0067] As shown in Fig. 5, the humidification fluid container 61 contains a humidification fluid L1a including water for humidifying the closed space SP shown in Fig. 4. The humidification fluid container 61 has a detection unit 61a that detects the liquid level in the humidification fluid container 61. The detection unit 61a has a first electrode 61b and a second electrode 61c.

[0068] The humidifying fluid L1a contains a conductive additive. The detection unit 61a detects the liquid level in the humidifying fluid storage unit 61 by the electrical resistance between the first electrode 61b and the second electrode 61c. When the liquid level of the humidifying fluid L1a stored in the humidifying fluid storage unit 61 is higher than the first predetermined height H1, the first electrode 61b and the second electrode 61c are electrically connected. When the liquid level of the humidifying fluid L1a stored in the humidifying fluid storage unit 61 is lower than the first predetermined height H1 and higher than the second predetermined height H2, the first electrode 61b and the second electrode 61c are not electrically connected. In this way, the detection unit 61a is configured to be able to determine whether the liquid level of the humidifying fluid L1a is higher than the first predetermined height H1 by changing the output level depending on whether the first electrode 61b is in contact with the liquid level or not.

[0069] When the detection unit 61a detects that the liquid level of the humidifying fluid L1a is above the first predetermined level H1, this means that the humidifying fluid storage unit 61 is full of the humidifying fluid L1a. In this embodiment, the full state of the humidifying fluid storage unit 61 is detected. Instead of detecting only the full state of the humidifying fluid storage unit 61, the empty or nearly empty state of the humidifying fluid storage unit 61 may be detected. Furthermore, the method for detecting the liquid level is not limited to the electrode method, and may be an optical method or a capacitance method.

[0070] The humidifying fluid storage unit 61 has a second atmosphere communication passage 61d and a second moisture permeable membrane 61e. The second atmosphere communication passage 61d connects the humidifying fluid storage unit 61 to the atmosphere. The second atmosphere communication passage 61d may have a labyrinth-like thin tube structure. The labyrinth-like thin tube structure refers to a tube structure having a complex path that is narrow and meanders to such an extent that air can enter and exit but the entry and exit of liquid is significantly restricted. The labyrinth-like thin tube structure suppresses evaporation of the liquid in the humidifying fluid storage unit 61.

[0071] The second moisture permeable membrane 61e is provided at the connection between the humidified fluid storage portion 61 and the second atmosphere communication passage 61d. The second moisture permeable membrane 61e allows gas to pass from the humidified fluid storage portion 61 to the second atmosphere communication passage 61d, while restricting the passage of liquid from the humidified fluid storage portion 61 to the second atmosphere communication passage 61d. To increase the efficiency of gas passing from the humidified fluid storage portion 61 to the second atmosphere communication passage 61d, it is desirable for the area of ​​the second moisture permeable membrane 61e to be large.

[0072] 5, the humidified fluid circulation mechanism 60 includes a first pump 63, which is an example of a first liquid delivery section capable of flowing the humidified fluid L1a through the circulation path 62, a first check valve 64, and a pressure adjustment valve 65. The first pump 63 drives the fluid through the circulation path 62. When the first pump 63 is driven, the liquid flowing through the supply flow path 62a is sent to the humidification chamber 55 in the cap 51a.

[0073] The first check valve 64 allows the flow of liquid from the humidifying fluid storage unit 61 side to the cap 51a side, and prevents the liquid from flowing back from the cap 51a side to the humidifying fluid storage unit 61 side due to a head difference. An on-off valve may be provided instead of the first check valve 64. When the on-off valve is opened, the liquid may flow from the humidifying fluid storage unit 61 side to the cap 51a side by driving the first pump 63. Opening the on-off valve is referred to as opening the valve or opening the valve. Closing the on-off valve is referred to as closing the valve or closing the valve.

[0074] The pressure regulating valve 65 allows liquid to flow from the cap 51a side to the humidifying fluid storage unit 61 side when a predetermined negative pressure is reached on the humidifying fluid storage unit 61 side, and always prevents liquid from flowing back from the humidifying fluid storage unit 61 side to the cap 51a side. The pressure regulating valve 65 adjusts the pressure difference of the head differential so that liquid does not flow from the cap 51a side to the humidifying fluid storage unit 61 side due to head pressure.

[0075] 5, the humidified fluid circulation mechanism 60 includes an adjusted water supply unit 66 capable of supplying adjusted water L1b, the main component of which is water for concentration adjustment, into the circulation path 62. The adjusted water supply unit 66 includes an adjusted water storage unit 66a as an example of a liquid storage unit, an adjusted water supply flow path 66b, a first on-off valve 66c, and a second check valve 66d. The adjusted water storage unit 66a stores the adjusted water L1b that can be supplied into the circulation path 62. The adjusted water supply flow path 66b communicates with the circulation path 62. The first on-off valve 66c is configured to be able to open and close the adjusted water supply flow path 66b.

[0076] 5, the humidified fluid circulation mechanism 60 includes supply flow paths 62a and 66b that communicate between the liquid introduction portion 104 (see FIG. 6) and the cap 51a, and a first pump 63 that sends the adjusted water L1b, which is the liquid in the adjusted water storage portion 66a, to the cap 51a. The supply flow path that communicates between the liquid introduction portion 104 and the cap 51a is composed of the supply flow path 62a that constitutes the circulation path 62 and the adjusted water supply flow path 66b.

[0077] The adjusted water storage section 66a has an outflow section 66f. The adjusted water storage section 66a communicates with the adjusted water supply flow path 66b at the outflow section 61g. The adjusted water supply flow path 66b communicates with the circulation path 62 at a first junction 62c of the circulation path 62. That is, the adjusted water storage section 66a communicates with the circulation path 62. It is preferable that the adjusted water storage section 66a is configured to be replaceable.

[0078] The adjusted water L1b supplied from the adjusted water storage section 66a into the circulation path 62 is replenishment water for adjusting the concentration to replenish the moisture evaporated from the humidification fluid L1a. The adjusted water L1b, which is an example of a liquid, is a liquid containing water and a preservative. More specifically, the adjusted water L1b is a liquid composed of pure water and a small amount of a preservative.

[0079] When the first on-off valve 66c is opened, the adjusted water storage section 66a and the circulation path 62 communicate with each other through the adjusted water supply flow path 66b. The second check valve 66d allows the flow of liquid from the adjusted water storage section 66a side to the circulation path 62 side, and prevents the backflow of liquid from the circulation path 62 side to the adjusted water storage section 66a side due to the head difference. The second check valve 66d may not be provided. When the second check valve 66d is not provided, the first pump 63 may cause the adjusted water L1b to flow from the adjusted water storage section 66a side to the cap 51a side by driving the first pump 63 when the first on-off valve 66c is opened.

[0080] As shown in FIG. 5, the humidified fluid circulation mechanism 60 included in the capping device 50 further includes a pressurized air supply unit 67. The pressurized air supply unit 67 is configured to be able to supply pressurized air into the circulation path 62. The pressurized air supply unit 67 includes a pressurized air supply path 67a communicating with the circulation path 62, a second on-off valve 67b, and a second pump 67c. When the second on-off valve 67b is opened, the second pump 67c communicates with the circulation path 62 through the pressurized air supply path 67a. The second pump 67c is, for example, a pressurizing pump. The second pump 67c applies pressure to the atmosphere to generate pressurized air, and supplies the pressurized air to the pressurized air supply path 67a.

[0081] In the circulation path 62, instead of providing the pressurized air supply unit 67 downstream of the first pump 63, an air supply unit may be provided upstream of the first pump 63 and downstream of the first junction 62c. The air supply unit may have an air communication passage communicating with the air and an on-off valve. Then, the air may be sent to the circulation path 62 by the first pump 63 in a state in which the circulation path 62 and the air are communicated with each other through the air communication passage by opening the on-off valve. That is, the capping device 50 may have an air supply unit that supplies air to the circulation path 62 between the first junction 62c where the adjustment water supply unit 66 and the circulation path 62 join and the inlet 55a of the cap 51a in the circulation path 62 through which the humidification fluid L1a flows. The capping device 50 may further have a pump that sends the air to the circulation path 62.

[0082] <Configuration of waste liquid recovery mechanism> As shown in FIG. 5, the waste liquid recovery mechanism 80 provided in the capping device 50 has a waste liquid recovery path 81, a third pump 82 as an example of a second liquid delivery section, a buffer chamber 83, a fourth pump 84, a third atmosphere communication passage 85, and a waste liquid storage section 86.

[0083] The waste liquid recovery path 81 includes a first waste liquid flow path 81a and a second waste liquid flow path 81b as an example of a waste liquid flow path. The first waste liquid flow path 81a communicates with a closed space SP formed by a recess 57 in the cap 51a shown in FIG. 4 at a discharge hole 56b of the cap 51a. The first waste liquid flow path 81a communicates with the closed space SP and the waste liquid storage section 86 through a buffer chamber 83. The downstream end of the first waste liquid flow path 81a is connected to the waste liquid storage section 86 via an inlet section 86b. The second waste liquid flow path 81b communicates with the wiper carriage 41 at a waste liquid outlet 43 of the wiper carriage 41. The second waste liquid flow path 81b communicates with the wiper carriage 41 and the waste liquid storage section 86.

[0084] During flushing, cleaning, and the like, liquid is discharged from the nozzles 22 of the liquid ejection head 21 as waste liquid L2. The waste liquid L2 is collected from within the cap 51a and flows into the first waste liquid flow path 81a. During wiping, liquid adhering to the nozzle surface 23 of the liquid ejection head 21 is wiped away and collected into the wiper carriage 41 as waste liquid L2. The waste liquid L2 is collected from within the wiper carriage 41 and flows into the second waste liquid flow path 81b. The waste liquid L2 collected by flushing or cleaning and the waste liquid L2 collected by wiping are sent to the waste liquid storage section 86 by the third pump 82. Then, the waste liquid L2 is stored in the waste liquid storage section 86.

[0085] As shown in Fig. 3, the five caps 51a included in the cap unit 51 of this embodiment each have a drain hole 56b shown in Fig. 4. Therefore, in this embodiment, the five drain holes 56b are connected to the first waste liquid flow path 81a, and the first waste liquid flow path 81a communicates the five drain holes 56b with the waste liquid storage section 86. When the cap device 50 has only one cap 51a, only the drain hole 56b of that cap 51a may be connected to the first waste liquid flow path 81a.

[0086] 5, in this embodiment, the fourth pump 84 is a pressure reducing pump. The fourth pump 84 lowers the air pressure in the buffer chamber 83 by discharging the air in the buffer chamber 83 to the outside of the buffer chamber 83 through the third atmosphere communication passage 85. This makes it easier for the waste liquid L2 discharged from the nozzle 22 of the liquid ejection head 21 into the cap 51a during flushing or cleaning to flow into the buffer chamber 83 through the first waste liquid flow path 81a. Note that the buffer chamber 83, the fourth pump 84, and the third atmosphere communication passage 85 may be omitted.

[0087] 5, the cap unit 51 having the cap 51a has an atmosphere opening mechanism 58. The atmosphere opening mechanism 58 has a first atmosphere communication passage 58a and a third opening / closing valve 58b.

[0088] In the cap unit 51, the first atmosphere communication passage 58a communicates each atmosphere communication hole 56a of the cap 51a with the atmosphere. The third on-off valve 58b is an on-off valve capable of opening and closing the first atmosphere communication passage 58a. In this embodiment, the atmosphere side of the first atmosphere communication passage 58a is opened. The third on-off valve 58b is configured so that when the cap unit 51 moves from the maintenance position shown by the two-dot chain line in FIG. 5 in the fourth direction D4 to the retracted position shown by the solid line in FIG. 5, the open part hits a wall (not shown) and the wall closes the first atmosphere communication passage 58a. That is, the third on-off valve 58b is opened and closed by the movement of the cap unit 51. During flushing or cleaning, the first atmosphere communication passage 58a is in an open state, and the liquid ejection head 21 discharges liquid into the cap 51a.

[0089] <Waste liquid box configuration> Next, a specific configuration of the waste liquid box 110 equipped with the conditioned water storage section 66a will be described with reference to FIGS.

[0090] 6, the liquid ejection device 11 includes a mounting part 100 to which a waste liquid box 110, which is an example of a liquid container, is detachably mounted. The waste liquid box 110 is detachably mounted to the mounting part 100. The waste liquid box 110 is configured to be able to store waste liquid L2 discharged from a waste liquid discharge part 103 of the mounting part 100. The waste liquid box 110 has, for example, a rectangular plate shape.

[0091] 6, the direction in which the waste liquid box 110 is mounted to the mounting part 100 is defined as a mounting direction A. A direction intersecting the mounting direction A and the vertical direction Z is defined as a width direction W. The mounting part 100 is configured so that the waste liquid box 110 can be attached and detached in the mounting direction A.

[0092] As shown in FIG. 6, the mounting part 100 includes a mounting part main body 101 and two positioning pins 102 protruding from a mounting surface 100A, which is a surface of the mounting part main body 101 on which the waste liquid box 110 is attached and detached. The mounting part 100 also includes a waste liquid discharge part 103, which is an example of a discharge part that discharges the waste liquid L2, and a liquid introduction part 104, which is an example of a liquid introduction part. The waste liquid discharge part 103 is formed of a needle-shaped tube part protruding from the mounting surface 100A of the mounting part main body 101. The waste liquid discharge part 103 is connected to the first waste liquid flow path 81a. Therefore, the waste liquid L2 collected from the multiple caps 51a is discharged from the waste liquid discharge part 103.

[0093] The liquid introduction part 104 is configured with a needle-shaped tube part protruding from the mounting surface 100A of the mounting part main body 101. The liquid introduction part 104 is connected to the adjustment water supply flow path 66b. Therefore, the adjustment water L1b introduced from the liquid introduction part 104 is replenished to the humidification fluid storage part 61 from the adjustment water supply flow path 66b via the circulation path 62.

[0094] 6, the mounting unit 100 has a substrate connecting portion 105. When the waste liquid box 110 is mounted on the mounting unit 100, the waste liquid box 110 is electrically connected to the substrate connecting portion 105.

[0095] As shown in FIG. 6 and FIG. 7, the downstream surface of the waste liquid box 110 in the mounting direction A is a mounting surface 110A facing the mounting part 100. The mounting surface 110A includes a waste liquid introduction part 115 connected to the waste liquid discharge part 103 and a liquid discharge part 116 connected to the liquid introduction part 104 when the waste liquid box 110 is mounted on the mounting part 100. The waste liquid box 110 includes an adjustment water storage part 66a that stores the adjustment water L1b that is led to the liquid introduction part 104. The adjustment water L1b, which is an example of a liquid, is a liquid that contains water for humidifying the cap 51a. The waste liquid discharge part 103 and the waste liquid introduction part 115 connected to each other form the inflow part 86b in FIG. 5. The liquid introduction part 104 and the liquid discharge part 116 connected to each other form the outflow part 66f in FIG. 5.

[0096] As shown in Fig. 6, the waste liquid box 110 includes a box body 111 having a rectangular plate shape with openings on both sides, a first cover 112 that closes a first opening 111A that opens upward of the box body 111, and a second cover 113 (see Fig. 8) that closes a second opening 111C (see Fig. 12) that opens downward of the box body 111. As shown in Figs. 6 and 7, the waste liquid box 110 includes a first cover 112 that covers the waste liquid storage section 86. The first cover 112 is fixed to the box body 111 in a liquid-tight sealed state. This fixing is, for example, by welding, but may also be by fastening with screws.

[0097] The waste liquid box 110 is provided with a waste liquid storage section 86 (see FIG. 11) capable of storing the waste liquid L2, and an adjusted water storage section 66a (see FIG. 12) for storing adjusted water L1b, which is an example of a liquid. An air vent 112A that communicates the inside of the waste liquid box 110 with the outside (atmosphere) is opened in the center of the upper surface of the first cover 112. When the waste liquid L2 is stored in the waste liquid box 110, air in an amount equal to the volume of the stored waste liquid L2 escapes from the air vent 112A. As a result, the waste liquid storage section 86 is stored with the waste liquid L2 until it becomes full to a predetermined amount.

[0098] 7, the mounting surface 110A of the waste liquid box 110 is provided with a plurality of (e.g., two) positioning holes 114 into which a plurality of (e.g., two) positioning pins 102 on the mounting part 100 side can be inserted, a waste liquid inlet 115 to which the waste liquid outlet 103 can be connected, and a liquid outlet 116 to which the liquid inlet 104 can be connected. The waste liquid inlet 115 is, for example, a hole into which the needle-shaped waste liquid inlet 115 can be inserted. The liquid outlet 116 is, for example, a hole into which the needle-shaped liquid inlet 104 can be inserted.

[0099] The positioning hole 114 is provided at a position opposite the positioning pin 102. The waste liquid inlet 115 is provided at a position opposite the waste liquid outlet 103. The waste liquid inlet 115 is fixed by a plurality of screws 131. The liquid outlet 116 is provided at a position opposite the liquid inlet 104. The liquid outlet 116 has a cylindrical mouth portion formed by joining a pair of semicircular arc-shaped protrusions formed on the end portions of the box body 111 and the second cover 113 (see FIG. 8) on the mounting surface 110A side.

[0100] Further, as shown in FIG. 7, the waste liquid box 110 includes a circuit board 117 having a connection terminal 117A that is electrically connected to the board connection portion 105 when the waste liquid box 110 is attached to the attachment portion 100. The circuit board 117 is provided at a position corresponding to the board connection portion 105 in the posture when the waste liquid box 110 is attached to the attachment portion 100. The circuit board 117 is fixed to a recessed portion at a position on the attachment surface 110A side of the waste liquid box 110 and toward the upper end of one end in the width direction W. When the waste liquid box 110 is attached to the attachment portion 100, the connection terminal 117A of the circuit board 117 and the board connection portion 105 on the attachment portion 100 side are electrically connected. For example, a memory element is mounted on the circuit board 117. Information regarding the amount of waste liquid L2 collected in the waste liquid box 110 is stored in the control unit 90 in the memory element.

[0101] As shown in FIGS. 6 and 7, a handle 118 for a user to grip the waste liquid box 110 is formed on the end of the waste liquid box 110 opposite the mounting surface 110A.

[0102] As shown in FIG. 8, the waste liquid box 110 includes a second cover 113 that covers the conditioned water storage section 66a. When the waste liquid box 110 is attached to the attachment section 100, the lower surface of the conditioned water storage section 66a is covered by the second cover 113. The second accommodating recess 111D (see FIG. 12) has a larger opening area than the first accommodating recess 111B (see FIG. 11). A part of the first accommodating recess 111B bulges out close to the second surface (bottom surface) of the box body 111, and the second accommodating recess 111D is formed in an area avoiding the bulging part. This is because it is necessary to ensure a larger volume of the waste liquid L2 than the volume of the conditioned water L1b.

[0103] 9, in a width direction W intersecting with the mounting direction A, the waste liquid discharge portion 103 is provided on one side, and the substrate connection portion 105 is provided on the other side. The liquid introduction portion 104 is provided between the waste liquid discharge portion 103 and the substrate connection portion 105 in the width direction W, and is provided at a lower position than the substrate connection portion 105 in the vertical direction Z.

[0104] 10, in a width direction W intersecting with the mounting direction A, the waste liquid inlet 115 is provided on one side, and the circuit board 117 is provided on the other side. The liquid outlet 116 is provided between the waste liquid inlet 115 and the circuit board 117 in the width direction W, and is provided at a lower position than the circuit board 117 in the vertical direction Z. As shown in FIG. 10, in the position where the waste liquid box 110 is mounted in the mounting part 100, the connection terminal 117A of the circuit board 117 is provided at a higher position than the center of the waste liquid inlet 115.

[0105] Fig. 11 shows the first surface side of the waste liquid box 110 when the first cover 112 is removed. As shown in Fig. 11, the first surface of the box body 111 is recessed to form a first storage recess 111B that is opened by a first opening 111A.

[0106] 11, a plurality of partition plates 111F extend inward from the inner surfaces of two opposing side walls extending in the long side direction of the inner circumferential wall of the first accommodating recess 111B. Also, a plurality of guide plates 111G protrude inward from the inner surfaces of two opposing side walls extending in the short side direction of the inner circumferential wall of the first accommodating recess 111B.

[0107] 11, the first accommodating recess 111B accommodates a plurality of absorbing members 120 capable of absorbing the waste liquid L2. The waste liquid accommodating section 86 of this embodiment is composed of the first accommodating recess 111B, a first cover 112 (see FIG. 13) covering the first accommodating recess 111B, a waste liquid chamber 86A (see also FIG. 13) partitioned by the first accommodating recess 111B and the first cover 112, and a plurality of absorbing members 120 accommodated in the waste liquid chamber 86A.

[0108] As shown in FIG. 11 and FIG. 15, the waste liquid chamber 86A has a space SP1 where the absorbing member 120 is not arranged in a portion corresponding to the waste liquid introduction portion 115, and the waste liquid introduction tube 115A extends from the waste liquid introduction portion 115 toward the upstream side in the mounting direction A into the space SP1. The waste liquid introduction tube 115A is held in a state where it is inserted into a tube insertion hole 121A of the holding member 121 housed in the space SP1. The holding member 121 is made of the same material as the absorbing member 120, for example, and functions as an absorbing member. The inner tip of the waste liquid introduction tube 115A opens into the hollow of the waste liquid introduction chamber 122. Therefore, the waste liquid L2 introduced from the waste liquid introduction portion 115 is first discharged into the waste liquid introduction chamber 122 through the waste liquid introduction tube 115A.

[0109] The multiple absorbing members 120 are press-fitted into the first accommodating recess 111B in a state partitioned by a partition plate 111F. Both end portions of the multiple absorbing members 120 in the mounting direction A are abutted against multiple guide plates 111G (only some of which are shown in FIG. 11) and are accommodated in a positioned state. The multiple absorbing members 120 are made of blocks of a predetermined shape and have the same thickness in the mounting direction A. Only the one disposed at the downstream end in the mounting direction A is thicker and has a shape that matches the shape of the first accommodating recess 111B.

[0110] Here, if the plurality of absorbing members 120 are in contact with each other, the waste liquid L2 will permeate into the adjacent absorbing member 120 through the contact portion. However, at the portion separated by the partition plate 111F, the two adjacent absorbing members 120 are adjacent to each other with a gap corresponding to the thickness of the partition plate 111F between them. Therefore, the waste liquid L2 is unlikely to permeate from one absorbing member 120 separated by the partition plate 111F to the other absorbing member 120. For this reason, grooves 125 and 126 are formed in the bottom of the waste liquid chamber 86A. In this example, the grooves 125 and 126 are formed by forming a notched recess in the bottom of the plurality of absorbing members 120. When the plurality of absorbing members 120 are accommodated in the first accommodation recess 111B, waste liquid flow paths 125A, 126A extending in the mounting direction A are formed by the grooves 125, 126 at the bottoms of the plurality of absorbing members 120, as shown in FIG. 11. The waste liquid L2 discharged into the waste liquid introduction chamber 122 flows through the waste liquid flow paths 125A, 126A extending in the mounting direction A and permeates the plurality of absorbing members 120 almost uniformly. That is, even if a gap is formed between two adjacent absorbing members 120 separated by the partition plate 111F, the waste liquid L2 is easily permeated throughout the plurality of absorbing members 120. In this way, the waste liquid L2 discharged into the waste liquid introduction chamber 122 permeates throughout the plurality of absorbing members 120.

[0111] 11, the plurality of absorbent members 120 accommodated in the first accommodation recess 111B have holes 123 formed in areas corresponding to the ventilation holes 112A. A moisture-permeable membrane 124 is fixed to the rear surface of the first cover 112 at positions corresponding to the ventilation holes 112A and the holes 123. The waste liquid chamber 86A partitioned by the first accommodation recess 111B and the first cover 112 communicates with the ventilation holes 112A via the moisture-permeable membrane 124. Since the moisture-permeable membrane 124 is located at a position corresponding to the holes 123, the moisture-permeable membrane 124 is separated from the waste liquid L2 absorbed in the absorbent member 120. Therefore, the inside of the waste liquid chamber 86A communicates with the atmosphere through the ventilation holes 112A, and even if the user tilts the waste liquid box 110 or holds it upside down, the waste liquid L2 will not leak from the ventilation holes 112A.

[0112] 11, a cutout hole 127 is formed in a portion of the plurality of absorption members 120 accommodated in the first accommodating recess 111B that corresponds to the liquid leading-out portion 116. This cutout hole 127 is used as a space for accommodating the shank of a screw 132 that fixes the leading-out member 68B of the adjustment water pack 68 accommodated in the second accommodating recess 111D when assembling the waste liquid box 110, or as a working space when fastening a nut or the like to the shank of the screw 132.

[0113] Fig. 12 shows the second surface side of the waste liquid box 110 when the second cover 113 is removed. As shown in Fig. 12, the second surface of the box body 111 is provided with a second storage recess 111D that is opened by a second opening 111C.

[0114] The conditioned water storage section 66a of this embodiment is composed of an conditioned water pack 68 stored in a storage chamber 66G defined by a second storage recess 111D and a second cover 113 covering the second storage recess 111D.

[0115] The conditioned water storage section 66a is an conditioned water pack 68, which is an example of a bag body that stores the conditioned water L1b. The conditioned water pack 68 includes a bag section 68A that stores the conditioned water L1b, and an outlet member 68B fixed to one end of the bag section 68A. The outlet member 68B has an outlet 116A at its tip that can be connected to the liquid introduction section 104.

[0116] The amount of the conditioned water L1b contained in the conditioned water storage portion 66a is set to a liquid amount that will cause the waste liquid storage portion 86 to become full with the waste liquid L2 before the conditioned water L1b contained in the conditioned water storage portion 66a runs out.

[0117] As shown in Figures 13 and 14, the waste liquid box 110 is mainly composed of, from the top, a first cover 112, an absorbing member 120, a box body 111, an adjustment water storage section 66a (adjustment water pack 68), and a second cover 113. The absorbing member 120 and the holding member 121 are stored in a first storage recess 111B of the box body 111. The waste liquid introduction section 115 is attached to the box body 111 by a screw 131 in a state in which a waste liquid introduction tube 115A is inserted into an assembly hole 119 opening in the mounting surface 110A of the box body 111. The first opening 111A opened upward of the box body 111 is closed by the first cover 112 welded to the upper surface of the box body 111, thereby defining a waste liquid chamber 86A in which the absorbing member 120 and the like are stored. Furthermore, a circuit board 117 is mounted on a board mounting portion 111H formed as a slope recessed at an upper portion of one end portion in the width direction W of the mounting surface 110A.

[0118] As shown in FIG. 14, the adjustment water pack 68 is accommodated in the second accommodation recess 111D. The outlet member 68B of the adjustment water pack 68 is assembled to a position corresponding to the liquid outlet portion 116 of the mounting surface 110A. The outlet member 68B is fixed to the box body 111 with two screws 132. The second opening 111C opened downwardly of the box body 111 is closed by the second cover 113 fixed to the lower surface of the box body 111 with a plurality of screws 133, thereby defining an accommodation chamber 66G in which the adjustment water pack 68 is accommodated. The outlet 116A of the adjustment water pack 68 is surrounded by the liquid outlet portion 116 in which the semi-cylindrical liquid outlet portion 116 on the box body 111 side and the semi-cylindrical liquid outlet portion 116 on the second cover 113 side are joined into a single cylinder.

[0119] In a position in which the waste liquid box 110 is mounted on the mounting portion 100, the upper surface of the absorbing member 120 is covered by the first cover 112. As shown in Fig. 13, in the box body 111, the first accommodating recess 111B and the second accommodating recess 111D are partitioned via a partition wall 111E. In this way, the waste liquid chamber 86A in which the collected waste liquid L2 is accommodated and the accommodation chamber 66G in which the adjustment water accommodation section 66a is accommodated are partitioned via the partition wall 111E. For this reason, the waste liquid L2 in the waste liquid chamber 86A does not enter the accommodation chamber 66G in which the adjustment water accommodation section 66a is accommodated.

[0120] <Electrical configuration of the liquid ejection device> 16, the liquid ejection device 11 includes a control unit 90 that controls the head unit 24, the wiper device 40, and the capping device 50. The capping device 50 includes a detector group 91 controlled by the control unit 90. The detector group 91 includes a detector 61a that detects the liquid level in the humidifying fluid storage unit 61. The detector 61a outputs the detection result to the control unit 90.

[0121] The control unit 90 has an interface unit 94, a CPU 95, a memory 96, a control circuit 97, and a drive circuit 98. The interface unit 94 transmits and receives data between a computer 99, which is an external device, and the liquid ejection device 11. The drive circuit 98 generates a drive signal that drives an actuator of the liquid ejection head 21.

[0122] The CPU 95 is an arithmetic processing device. The memory 96 is a storage device that secures an area for storing programs of the CPU 95 or a working area, and has storage elements such as a RAM and an EEPROM. The CPU 95 controls the head unit 24, the wiper device 40, the cap device 50, etc. via a control circuit 97 in accordance with the programs stored in the memory 96.

[0123] The memory 96 stores a plurality of programs, including a program shown in the flowchart of FIG. 17 that causes the CPU 95 of the control unit 90 to execute a circulation operation, and a program shown in the flowchart of FIG. 18 that causes the CPU 95 to execute a concentration adjustment operation.

[0124] <About the circulation of humidified fluid> The circulation operation in the maintenance method of the capping device will now be described. As shown in Fig. 19, the capping device 50 performs a circulation operation. During the circulation operation, the first on-off valve 66c is closed, and the control unit 90 causes the humidified fluid circulation mechanism 60 to flow the humidified fluid L1a in the circulation path 62 in the direction of the solid arrow shown in Fig. 19. Then, the control unit 90 checks the amount of water evaporation from the humidified fluid L1a.

[0125] A circulation path is formed by a humidification fluid storage portion 61 that stores humidification fluid L1a containing water for humidifying the closed space SP shown in Fig. 4, a supply flow path 62a that connects the humidification fluid storage portion 61 to the cap 51a, a recovery flow path 62b that connects the cap 51a to the humidification fluid storage portion 61, and the humidification chamber 55 shown in Fig. 4 in the cap 51a. Note that it is desirable that the internal pressure in the cap 51a during the circulation operation be set to a value equal to or lower than the meniscus withstand pressure of the liquid ejection head 21 by adjusting the circulation flow rate by the first pump 63.

[0126] As shown in FIG. 19, in the circulation operation of the humidified fluid L1a, the humidified fluid L1a flows in the circulation path 62 in the direction of the solid arrow shown in FIG. 19 and circulates through the circulation path. The control unit 90 causes the humidified fluid L1a to flow in the circulation path 62, so that the humidified fluid L1a flows through a single, winding flow path in the humidifying chamber 55. Moisture from the humidified fluid L1a mainly evaporates in the humidifying chamber 55 in the cap 51a. Then, for example, at the timing when the humidified fluid L1a in the humidifying chamber 55 flows into the humidifying fluid storage unit 61 and the humidified fluid L1a in the humidifying fluid storage unit 61 flows into the humidifying chamber 55, the control unit 90 stops the flow of the humidified fluid L1a and checks the amount of moisture evaporated from the humidified fluid L1a. That is, the purpose of the circulation operation in the maintenance method of the cap device 50 includes checking the amount of moisture evaporated from the humidified fluid L1a.

[0127] As shown in FIG. 19, the control unit 90 periodically executes the circulation operation by managing the time using a timer or the like. For example, when the power supply of the liquid ejection device 11 is turned on, the control unit 90 executes the circulation operation once a day. At the end of the flow of the circulation operation described later, the control unit 90 acquires information on the liquid level in the humidifying fluid storage unit 61 from the detection unit 61a in order to confirm the amount of water evaporation from the humidifying fluid L1a. If the amount of water evaporation in the cap 51a is large, the liquid level in the humidifying fluid storage unit 61 becomes low. The amount of water evaporation increases during the time when the cap 51a is located at the retracted position shown in FIG. 2 and FIG. 5, that is, during the time when the cap 51a does not form the closed space SP surrounding the opening 22a of the nozzle 22 shown in FIG. 4. Therefore, the control unit 90 may execute the circulation operation by managing the time when the cap 51a is located at the retracted position for each temperature and humidity environment. In addition, the control unit 90 may also perform the circulation operation before recording is performed on the medium M for the first time after the liquid ejection device 11 is installed, before recording is performed on the medium M for the first time after the cap unit 51 is replaced with a new cap unit 51, and before recording is performed on the medium M for the first time after the adjustment water storage section 66a is replaced with a full adjustment water storage section 66a.

[0128] In order to reduce the frequency of the circulation operation, it is desirable that the humidification fluid storage section 61 has a large liquid surface area relative to the depth within the humidification fluid storage section 61. This makes it possible to reduce changes in the height of the liquid surface when the amount of liquid within the humidification fluid storage section 61 changes due to evaporation of moisture contained in the humidification fluid L1a. Also, in order to make the change in concentration of the humidification fluid L1a caused by evaporation of moisture contained in the humidification fluid L1a from the humidification fluid L1a as gradual as possible, it is desirable to make the volume of the humidification fluid storage section 61 as large as possible within the size of the liquid ejection device 11.

[0129] <About the humidification fluid concentration adjustment operation> The concentration adjustment operation in the maintenance method of the capping device will be described. As shown in Fig. 19, the capping device 50 performs a concentration adjustment operation. During the concentration adjustment operation, the first on-off valve 66c is open, and the control unit 90 causes the humidification fluid L1a to flow in the circulation path 62 in the direction of the solid arrow shown in Fig. 19 in the humidification fluid circulating mechanism 60. At this time, because the first on-off valve 66c is open, the adjustment water L1b in the adjustment water supply unit 66 flows in the direction of the dashed arrow shown in Fig. 19 and is supplied into the circulation path 62. In other words, the concentration adjustment operation in the maintenance method for the capping device 50 includes supplying the adjustment water L1b into the circulation path 62 by the adjustment water supply unit 66 and flowing the humidification fluid L1a in the circulation path 62.

[0130] The concentration adjustment operation is executed by the control unit 90 at the end of the flow of the circulation operation described above, when the liquid level in the humidifying fluid storage unit 61 is detected by the detection unit 61a to be below the first predetermined level H1 when the control unit 90 acquires information on the liquid level in the humidifying fluid storage unit 61. That is, when performing the concentration adjustment operation when the detection unit 61a detects that the liquid level in the humidifying fluid storage unit 61 is below the predetermined level, the capping device 50 supplies the adjustment water L1b in the adjustment water storage unit 66a into the circulation path 62 until it detects that the liquid level has reached or exceeded the predetermined level. Then, the humidifying fluid L1a is caused to flow in the circulation path 62.

[0131] Moisture evaporates from the humidifying fluid L1a in the cap 51a, and the humidifying fluid L1a circulates in the circulation path 62 by the above-mentioned circulation operation. As a result, the moisture in the humidifying fluid storage unit 61 also decreases, so the liquid level in the humidifying fluid storage unit 61 decreases. As the evaporation progresses further, the liquid level in the humidifying fluid storage unit 61 becomes lower than the first predetermined level H1. The first predetermined level H1 is set so that the concentration of the humidifying fluid L1a at this time is higher than the predetermined concentration. The control unit 90 executes a concentration adjustment operation, so that the adjusted water L1b in the adjusted water storage unit 66a is supplied into the circulation path 62 so that the liquid level becomes higher than the first predetermined level H1. As a result, approximately the same amount of water as the water evaporated in the cap 51a is supplied into the circulation path 62, and the concentration of the humidifying fluid L1a becomes lower than the predetermined concentration. That is, the concentration of the humidification fluid L1a returns to the concentration of the humidification fluid L1a before the moisture evaporated inside the cap 51a.

[0132] In the concentration adjustment operation, the control unit 90 opens the first on-off valve 66c and supplies the adjusted water L1b in the adjusted water storage unit 66a into the circulation path 62. Then, when the control unit 90 determines that the liquid level in the humidifying fluid storage unit 61 has become higher than the first predetermined height H1, it closes the first on-off valve 66c and performs the above-mentioned circulation operation to cause the humidifying fluid L1a in the humidifying fluid storage unit 61 to flow through the circulation path 62. That is, the concentration adjustment operation in the maintenance method for the capping device 50 includes opening the first on-off valve 66c when supplying the adjusted water L1b in the adjusted water storage unit 66a into the circulation path 62, and closing the first on-off valve 66c when causing the humidifying fluid L1a to flow through the circulation path 62.

[0133] At the first junction 62c of the circulation path 62, the humidifying fluid L1a flowing from the humidifying fluid storage unit 61 and the adjusting water L1b flowing from the adjusting water supply unit 66 join together. When the volume of the adjusting water L1b flowing from the adjusting water supply unit 66 is greater than the volume of the humidifying fluid L1a flowing from the humidifying fluid storage unit 61, the rate of change of the liquid level in the humidifying fluid storage unit 61 increases, resulting in greater variation in the liquid level detection, making it difficult to detect the liquid level in a timely manner. For this reason, it is desirable to set the pressure loss of the flow path on the adjusting water supply unit 66 side at the first junction 62c to be the same as or greater than the pressure loss of the flow path on the humidifying fluid storage unit 61 side.

[0134] <About the cap replacement preparation operation> Furthermore, when the cap 51a is replaced, a cap replacement preparation operation is performed. The cap replacement preparation operation is an operation performed by the cap device 50 when the cap 51a is replaced. Before the cap 51a is replaced, the humidification fluid L1a inside the cap 51a is collected. In the cap device 50 of this embodiment, when replacing the cap, the cap unit 51 shown in FIG. 3 is replaced. Note that a configuration in which the cap 51a is replaced individually may also be used.

[0135] During the cap replacement preparation operation, the first on-off valve 66c is closed and the second on-off valve 67b is open, and the control unit 90 causes the pressurized air supply unit 67 of the humidified fluid circulation mechanism 60 to flow pressurized air in the pressurized air supply passage 67a in the direction of the dashed arrow shown in FIG. 17. At this time, the pressurized air supply unit 67 supplies pressurized air into the circulation path 62, so that the humidified fluid L1a in the flow path from the second junction 66e to the inlet 61f of the circulation path formed by the circulation path 62 is pushed into the humidified fluid storage unit 61. Then, the flow path from the second junction 66e to the inlet 61f is filled with air. As a result, the humidified fluid L1a in the cap 51a is collected in the humidified fluid storage unit 61.

[0136] Since moisture in the humidifying fluid L1a evaporates within the cap 51a, the concentration of the humidifying fluid L1a in the cap 51a is high. As a result, when the humidifying fluid L1a in the cap 51a is collected into the humidifying fluid storage section 61, the concentration of the humidifying fluid L1a in the humidifying fluid storage section 61 becomes high. Also, when the humidifying fluid L1a in the cap 51a is collected into the humidifying fluid storage section 61, a small amount of the highly concentrated humidifying fluid L1a remains in the cap 51a. As a result, the amount of humidifying fluid L1a in the humidifying fluid storage section 61 decreases accordingly.

[0137] <Operation before replacing the conditioned water storage unit> The conditioned water storage unit pre-exchange operation that is performed before exchanging the conditioned water storage unit 66a when it is determined that the conditioned water L1b in the conditioned water storage unit 66a has run out will be described.

[0138] The conditioned water storage unit pre-exchange operation is an operation executed by the control unit 90 when the amount of conditioned water L1b in the conditioned water storage unit 66a reaches an amount at which it is determined that the conditioned water storage unit 66a needs to be replaced. In this embodiment, since the conditioned water storage unit 66a is stored in the same waste liquid box 110 as the waste liquid storage unit 86, the control unit 90 executes the conditioned water storage unit pre-exchange operation even at the time of replacement when the waste liquid storage unit 86 becomes full of the waste liquid L2.

[0139] In this embodiment, in the above-described concentration adjustment operation, when the first pump 63 is driven for the third predetermined time T3 and the detection unit 61a detects that the liquid level in the humidifying fluid storage unit 61 is below the first predetermined height H1, the control unit 90 determines that the adjusting water in the adjusting water storage unit 66a has run out. In other words, when the concentration of the humidifying fluid L1a in the circulation path 62 cannot be restored to the concentration before the water evaporated in the cap 51a, the control unit 90 determines that the adjusting water storage unit 66a needs to be replaced.

[0140] When it is determined that the adjustment water container 66a needs to be replaced, the same operation as the cap replacement preparation operation described above is executed by the control unit 90. Then, after the humidification fluid L1a in the cap 51a is collected, the first parameter table for flushing is switched to the second parameter table when the adjustment water L1b in the adjustment water container 66a runs out until the adjustment water container 66a is replaced.

[0141] The parameter table is a table in which the conditions and number of times for flushing are described, and flushing is performed based on this table. When the humidifying fluid L1a in the cap 51a is collected, the closed space SP in the cap 51a is not humidified by the humidifying fluid L1a, so the control unit 90 performs dummy ejection, which is the ejection of liquid unrelated to printing, into the closed space SP in the cap 51a to humidify the nozzles 22. Therefore, the conditions and number of times for flushing are changed to parameters suitable for humidifying the nozzles 22.

[0142] Note that the above-mentioned circulation operation, which was performed periodically until the adjustment water storage section 66a is replaced, is not executed. When the adjustment water storage section 66a is replaced, the control section 90 starts the above-mentioned concentration adjustment operation after returning the second parameter table to the first parameter table before the parameter table was switched. Then, after that, the above-mentioned circulation operation is also executed periodically.

[0143] <Liquid ejected from the liquid ejection head> The ink ejected by the liquid ejection device 11 will be described in detail below. The ink used in the liquid ejection device 11 contains a resin in its composition, and does not substantially contain glycerin, which has a boiling point of 290°C under 1 atmospheric pressure. If the ink substantially contains glycerin, the drying properties of the ink are significantly reduced. As a result, not only do image shading unevenness become noticeable on various media, particularly on non-ink-absorbent or low-ink-absorbent media, but the ink does not adhere well. Furthermore, it is preferable that the ink does not substantially contain alkyl polyols (other than the above-mentioned glycerin) with a boiling point of 280°C or higher under 1 atmospheric pressure.

[0144] Here, "substantially free" in this specification means that the amount of glycerin is not more than the amount that fully exerts the significance of adding it. Quantitatively speaking, it is preferable that the ink does not contain glycerin in an amount of 1.0% by mass or more, more preferably 0.5% by mass or more, even more preferably 0.1% by mass or more, even more preferably 0.05% by mass or more, and particularly preferably 0.01% by mass or more, based on the total mass of the ink (100% by mass). And it is most preferable that the ink does not contain glycerin in an amount of 0.001% by mass or more.

[0145] Next, additives (components) that are or can be contained in the ink will be described. [1. Coloring materials] The ink may include a colorant selected from pigments and dyes.

[0146] [1-1. Pigments] By using a pigment as a coloring material, the light resistance of the ink can be improved. Either an inorganic pigment or an organic pigment can be used as the pigment. The inorganic pigment is not particularly limited, but examples thereof include carbon black, iron oxide, titanium oxide, and silica oxide.

[0147] The organic pigment is not particularly limited, but examples thereof include quinacridone pigments, quinacridonequinone pigments, dioxazine pigments, phthalocyanine pigments, anthrapyrimidine pigments, anthanthrone pigments, indanthrone pigments, flavanthrone pigments, perylene pigments, diketopyrrolopyrrole pigments, perinone pigments, quinophthalone pigments, anthraquinone pigments, thioindigo pigments, benzimidazolone pigments, isoindolinone pigments, azomethine pigments, and azo pigments. Specific examples of organic pigments include the following:

[0148] Pigments used in cyan inks include CI Pigment Blue 1, 2, 3, 15, 15:1, 15:2, 15:3, 15:4, 15:6, 15:34, 16, 18, 22, 60, 65, and 66, and CI Vat Blue 4 and 60. Of these, CI Pigment Blue 15:3 and 15:4 are preferred.

[0149] Pigments used in magenta inks include CI Pigment Red 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 14, 15, 16, 17, 18, 19, 21, 22, 23, 30, 31, 32, 37, 38, 40, 41, 42, 48(Ca), 48(Mn), 57(Ca), 57:1, 88, 112, 114 , 122, 123, 144, 146, 149, 150, 166, 168, 170, 171, 175, 176, 177, 178, 179, 184, 185, 187, 202, 209, 219, 224, 245, 254, 264, CI Pigment Violet 19, 23, 32, 33, 36, 38, 43, 50. Among them, one or more selected from the group consisting of CI Pigment Red 122, CI Pigment Red 202, and CI Pigment Violet 19 are preferred.

[0150] Examples of pigments used in the yellow ink include CI Pigment Yellow 1, 2, 3, 4, 5, 6, 7, 10, 11, 12, 13, 14, 16, 17, 24, 34, 35, 37, 53, 55, 65, 73, 74, 75, 81, 83, 93, 94, 95, 97, 98, 99, 108, 109, 110, 113, 114, 117, 120, 124, 128, 129, 133, 138, 139, 147, 151, 153, 154, 155, 167, 172, 180, 185, and 213. Among these, one or more selected from the group consisting of CI Pigment Yellow 74, 155, and 213 are preferred.

[0151] Pigments used in inks of colors other than those mentioned above, such as green ink and orange ink, include conventionally known pigments. The average particle diameter of the pigment is preferably 250 nm or less, since this can prevent clogging in the nozzle 22 and improves the ejection stability. The average particle diameter in this specification is based on volume. For example, the average particle diameter can be measured using a particle size distribution measuring device that uses the laser diffraction scattering method as its measurement principle. For example, the particle size distribution measuring device can be a particle size distribution meter that uses the dynamic light scattering method as its measurement principle (e.g., Microtrack UPA manufactured by Nikkiso Co., Ltd.).

[0152] [1-2.Dye] A dye can be used as the coloring material. The dye is not particularly limited, and acid dyes, direct dyes, reactive dyes, and basic dyes can be used. The content of the coloring material is preferably 0.4 to 12% by mass, more preferably 2% by mass or more and 5% by mass or less, based on the total mass of the ink (100% by mass).

[0153] [2. Resin] The ink contains a resin. When the ink contains a resin, a resin film is formed on the medium, which results in the ink being sufficiently fixed on the medium, and mainly exhibits the effect of improving the abrasion resistance of the image. For this reason, it is preferable that the resin emulsion is a thermoplastic resin. The thermal deformation temperature of the resin is preferably 40° C. or higher, and more preferably 60° C. or higher, since this has the advantageous effect of making the nozzle 22 less likely to clog and providing the medium with abrasion resistance.

[0154] Here, the "heat distortion temperature" in this specification is a temperature value expressed by glass transition temperature (Tg) or minimum film forming temperature (MFT). In other words, "heat distortion temperature is 40°C or higher" means that either Tg or MFT is 40°C or higher. Since it is easier to grasp the superiority or inferiority of the redispersibility of the resin with MFT than with Tg, the heat distortion temperature is preferably a temperature value expressed by MFT. If the ink has excellent redispersibility of the resin, the ink does not solidify and the nozzle 22 is less likely to become clogged.

[0155] Specific examples of the thermoplastic resin include, but are not limited to, poly(meth)acrylic acid esters or copolymers thereof, polyacrylonitrile or copolymers thereof, (meth)acrylic polymers such as polycyanoacrylate, polyacrylamide, and poly(meth)acrylic acid, polyethylene, polypropylene, polybutene, polyisobutylene, and polystyrene, and copolymers thereof, as well as polyolefin polymers such as petroleum resins, coumarone-indene resins, and terpene resins, vinyl acetate or vinyl alcohol polymers such as polyvinyl acetate or copolymers thereof, polyvinyl alcohol, polyvinyl acetal, and polyvinyl ether, halogen-containing polymers such as polyvinyl chloride or copolymers thereof, polyvinylidene chloride, fluororesins, and fluororubber, nitrogen-containing vinyl polymers such as polyvinylcarbazole, polyvinylpyrrolidone or copolymers thereof, polyvinylpyridine, and polyvinylimidazole, diene polymers such as polybutadiene or copolymers thereof, polychloroprene, and polyisoprene (butyl rubber), as well as other ring-opening polymerization resins, condensation polymerization resins, and natural polymer resins.

[0156] The content of the resin is preferably 1 to 30% by mass, more preferably 1 to 5% by mass, based on the total mass (100% by mass) of the ink. When the content is within the above range, the gloss and abrasion resistance of the overcoat image formed can be made even better. Examples of the resin that may be contained in the ink include a resin dispersant, a resin emulsion, and a wax.

[0157] [2-1. Resin emulsion] The ink may contain a resin emulsion. When the medium is heated, the resin emulsion preferably forms a resin coating together with a wax (emulsion), thereby exerting an effect of sufficiently fixing the ink on the medium and improving the abrasion resistance of the image. Due to the above effect, when a medium is printed with an ink containing the resin emulsion, the ink has excellent abrasion resistance, particularly on a medium that is non-absorbent or has low ink absorption.

[0158] The resin emulsion functioning as a binder is contained in the ink in an emulsion state. By containing the resin functioning as a binder in the ink in an emulsion state, it is easy to adjust the viscosity of the ink to an appropriate range for the inkjet recording method, and the storage stability and ejection stability of the ink can be improved.

[0159] Examples of resin emulsions include, but are not limited to, homopolymers or copolymers of (meth)acrylic acid, (meth)acrylic acid esters, acrylonitrile, cyanoacrylate, acrylamide, olefin, styrene, vinyl acetate, vinyl chloride, vinyl alcohol, vinyl ether, vinyl pyrrolidone, vinyl pyridine, vinyl carbazole, vinyl imidazole, and vinylidene chloride, fluororesins, and natural resins. Among these, either methacrylic resin or styrene-methacrylic acid copolymer resin is preferred, either acrylic resin or styrene-acrylic acid copolymer resin is more preferred, and styrene-acrylic acid copolymer resin is even more preferred. The above copolymer may be in any form of random copolymer, block copolymer, alternating copolymer, or graft copolymer.

[0160] In order to improve the storage stability and ejection stability of the ink, the average particle size of the resin emulsion is preferably in the range of 5 nm to 400 nm, and more preferably in the range of 20 nm to 300 nm. The content of the resin emulsion is preferably in the range of 0.5 to 7 mass% with respect to the total mass of the ink (100 mass%). If the content is within the above range, the solid content can be reduced, thereby improving the ejection stability.

[0161] [2-2. Wax] The ink may contain a wax. When the ink contains a wax, the ink has better fixability on non-ink absorbing and low ink absorbing media. Among them, the wax is preferably an emulsion type. The wax is not limited to the following, but may be, for example, a polyethylene wax, a paraffin wax, or a polyolefin wax, and among them, the polyethylene wax described below is preferable. In this specification, the term "wax" mainly refers to solid wax particles dispersed in water using a surfactant described below.

[0162] The ink contains polyethylene wax, which can provide the ink with excellent abrasion resistance. The average particle size of the polyethylene wax is preferably in the range of 5 nm to 400 nm, and more preferably in the range of 50 nm to 200 nm, in order to further improve the storage stability and ejection stability of the ink.

[0163] The content of the polyethylene wax (solid content equivalent) is preferably, independently of one another, in the range of 0.1 to 3 mass% relative to the total mass of the ink (100 mass%), more preferably in the range of 0.3 to 3 mass%, and even more preferably in the range of 0.3 to 1.5 mass%. If the content is within the above range, the ink can be well solidified and fixed even on a non-ink-absorbent or low-ink-absorbent medium, and the storage stability and ejection stability of the ink can be further improved.

[0164] [3. Surfactants] The ink may contain a surfactant. Examples of surfactants include, but are not limited to, nonionic surfactants. Nonionic surfactants have the effect of spreading the ink evenly on a medium. For this reason, when printing is performed using ink containing a nonionic surfactant, a high-definition image with almost no bleeding can be obtained. Examples of such nonionic surfactants include, but are not limited to, silicon-based, polyoxyethylene alkyl ether-based, polyoxypropylene alkyl ether-based, polycyclic phenyl ether-based, sorbitan derivative, and fluorine-based surfactants, among which silicon-based surfactants are preferred.

[0165] The content of the surfactant is preferably in the range of 0.1% by mass or more and 3% by mass or less relative to the total mass of the ink (100% by mass), in order to further improve the storage stability and ejection stability of the ink.

[0166] [4. Organic solvents] The ink may contain a known volatile water-soluble organic solvent. However, as described above, it is preferable that the ink does not substantially contain glycerin (having a boiling point of 290° C. under 1 atmosphere), which is a type of organic solvent, and does not substantially contain alkyl polyols (other than the above-mentioned glycerin) having a boiling point of 280° C. or higher under an equivalent pressure of 1 atmosphere.

[0167] [5. Aprotic polar solvents] The ink may contain an aprotic polar solvent. By including an aprotic polar solvent in the ink, the resin particles contained in the ink dissolve, so clogging of the nozzle 22 during printing can be effectively suppressed. In addition, since the ink has the property of dissolving a medium such as vinyl chloride, the adhesion of the image is improved.

[0168] The aprotic polar solvent is not particularly limited, but preferably contains at least one selected from pyrrolidones, lactones, sulfoxides, imidazolidinones, sulfolanes, urea derivatives, dialkylamides, cyclic ethers, and amide ethers. Representative examples of pyrrolidones include 2-pyrrolidone, N-methyl-2-pyrrolidone, and N-ethyl-2-pyrrolidone. Representative examples of lactones include γ-butyrolactone, γ-valerolactone, and ε-caprolactone. Representative examples of sulfoxides include dimethyl sulfoxide and tetramethylene sulfoxide.

[0169] Representative examples of imidazolidinones include 1,3-dimethyl-2-imidazolidinone, representative examples of sulfolanes include sulfolane and dimethylsulfolane, representative examples of urea derivatives include dimethylurea and 1,1,3,3-tetramethylurea, representative examples of dialkylamides include dimethylformamide and dimethylacetamide, and representative examples of cyclic ethers include 1,4-dioxane and tetrahydrofuran.

[0170] Among these, from the viewpoint of the above-mentioned effects, pyrrolidones, lactones, sulfoxides, and amide ethers are particularly preferable, and 2-pyrrolidone is the most preferable. The content of the above aprotic polar solvent is preferably in the range of 3 to 30% by mass, and more preferably in the range of 8 to 20% by mass, based on the total mass of the ink (100% by mass).

[0171] [6. Other ingredients] In addition to the above components, the ink may further contain a mildew inhibitor, a rust inhibitor, a chelating agent, and the like.

[0172] <About humidifying fluid> The components of the surfactant mixed into the humidifying fluid L1a will be described. Examples of surfactants that can be used include cationic surfactants such as alkylamine salts and quaternary ammonium salts; anionic surfactants such as dialkyl sulfosuccinates, alkyl naphthalene sulfonates, and fatty acid salts; amphoteric surfactants such as alkyl dimethylamine oxides and alkyl carboxybetaines; and nonionic surfactants such as polyoxyethylene alkyl ethers, polyoxyethylene alkyl allyl ethers, acetylene glycols, and polyoxyethylene-polyoxypropylene block copolymers. Of these, anionic surfactants or nonionic surfactants are particularly preferred.

[0173] The content of the surfactant is preferably 0.1 to 5.0% by mass relative to the total mass of the humidifying fluid L1a. Furthermore, from the viewpoint of foaming property and defoaming property after foaming, the content of the surfactant is preferably 0.5 to 1.5% by mass relative to the total mass of the humidifying fluid L1a. The surfactant may be one type or two or more types. The surfactant contained in the humidifying fluid L1a is preferably the same as the surfactant contained in the ink (liquid). For example, when the surfactant contained in the ink (liquid) is a nonionic surfactant, examples of the nonionic surfactant include, but are not limited to, silicon-based, polyoxyethylene alkyl ether-based, polyoxypropylene alkyl ether-based, polycyclic phenyl ether-based, sorbitan derivative, and fluorine-based surfactants, and among them, silicon-based surfactants are preferred.

[0174] In particular, in order to make the foam height immediately after foaming and 5 minutes after foaming using the Ross-Miles method within the above range (foam height immediately after foaming is 50 mm or more, and foam height 5 minutes after foaming is 5 mm or less), it is preferable to use an adduct in which ethylene oxide (EO) is added to acetylenic diol with an added mole number of 4 to 30 as a surfactant, and the content of the adduct is 0.1 to 3.0% by weight based on the total weight of the cleaning solution. Furthermore, in order to make the foam height immediately after foaming and 5 minutes after foaming using the Ross-Miles method within the above preferred range (foam height immediately after foaming is 100 mm or more, and foam height 5 minutes after foaming is 5 mm or less), it is preferable to use an adduct in which ethylene oxide (EO) is added to acetylenic diol with an added mole number of 10 to 20, and the content of the adduct is 0.5 to 1.5% by weight based on the total weight of the cleaning solution. However, if the content of the ethylene oxide adduct of acetylenic diol is too high, the critical micelle concentration may be reached, resulting in an emulsion.

[0175] The surfactant has a function of making the aqueous ink easily wet and spread on the recording medium. There is no particular limitation on the surfactant that can be used in the present invention, and examples of the surfactant that can be used include anionic surfactants such as dialkyl sulfosuccinates, alkyl naphthalene sulfonates, and fatty acid salts; nonionic surfactants such as polyoxyethylene alkyl ethers, polyoxyethylene alkyl allyl ethers, acetylene glycols, and polyoxyethylene-polyoxypropylene block copolymers; cationic surfactants such as alkylamine salts and quaternary ammonium salts; silicone surfactants; and fluorine-based surfactants.

[0176] The surfactant has the effect of breaking down and dispersing the aggregates due to the interfacial activity between the humidifying fluid L1a and the aggregates. In addition, the surfactant acts to lower the surface tension of the cleaning liquid, making it easier for the cleaning liquid to penetrate between the aggregates and the nozzle surface 23, and therefore easier to peel off the aggregates from the nozzle surface 23.

[0177] Any surfactant can be suitably used as long as it is a compound having a hydrophilic portion and a hydrophobic portion in the same molecule. Specific examples are preferably those represented by the following formulas (I) to (IV). That is, examples include polyoxyethylene alkyl phenyl ether surfactants of the following formula (I), acetylene glycol surfactants of the following formula (II), polyoxyethylene alkyl ether surfactants of the following formula (III), and polyoxyethylene polyoxypropylene alkyl ether surfactants of the following formula (IV).

[0178] [ka] (R is an optionally branched hydrocarbon chain having 6 to 14 carbon atoms, k is 5 to 20)

[0179] [ka] (m, n≦20,0 <m+n≦40)

[0180] [ka] (R is a hydrocarbon chain having 6 to 14 carbon atoms that may be branched, and n is 5 to 20.)

[0181] [ka] (R is a hydrocarbon chain with 6 to 14 carbon atoms, m and n are numbers up to 20) Other than the compounds of the formulas (I) to (IV), for example, alkyl and aryl ethers of polyhydric alcohols such as diethylene glycol monophenyl ether, ethylene glycol monoallyl ether, diethylene glycol monophenyl ether, diethylene glycol monobutyl ether, propylene glycol monobutyl ether, and tetraethylene glycol chlorophenyl ether, nonionic surfactants such as polyoxyethylene polyoxypropylene block copolymers, fluorine-based surfactants, and lower alcohols such as ethanol and 2-propanol can be used, with diethylene glycol monobutyl ether being particularly preferred.

[0182] <effect> Next, the operation of this embodiment will be described. Before the liquid ejection device 11 is assembled and shipped from the factory, a humidification fluid filling operation is performed, and the liquid ejection device 11 is shipped from the factory in a state in which a predetermined amount of humidification fluid L1a is contained in the humidification fluid container 61. At the time of this shipment, the humidification fluid L1a in the cap 51a is discharged in advance, and the cap 51a is in a state in which there is almost no humidification fluid L1a.

[0183] When the liquid ejection device 11 shipped from the factory arrives at the user, the user installs the liquid ejection device 11. The user attaches the waste liquid box 110 to the attachment part 100 of the liquid ejection device 11. As a result, the waste liquid storage part 86 is connected to the first waste liquid flow path 81a, and the adjustment water storage part 66a is connected to the adjustment water supply flow path 66b. Thereafter, the user performs an initial operation using the operation part 15 before using the liquid ejection device 11 for printing. The control part 90 executes the flow of the circulation operation shown in FIG. 17 as a preparatory operation. When the first circulation operation is completed, the liquid ejection device 11 becomes capable of recording on the medium M. Thereafter, the control part 90 uses a timer to manage at least one of the time periods, such as the recording time and the elapsed time since the end of the previous circulation operation, and executes the circulation operation at a predetermined timing when the time reaches the set time.

[0184] Next, the flow of the circulation operation executed by the control unit 90 will be described with reference to the flowchart shown in FIG. In step S101, the control unit 90 determines whether the first on-off valve 66c is in a closed state. If the first on-off valve 66c is in a closed state, the process proceeds to step S103. If the first on-off valve 66c is in an open state, the process proceeds to step S102. Then, in step S102, the control unit 90 closes the first on-off valve 66c.

[0185] In step S103, the control unit 90 drives the first pump 63 for a first predetermined time T1 with the first on-off valve 66c in a closed state, thereby causing the humidification fluid L1a to flow in the circulation path 62 in the direction of the solid arrow shown in FIG.

[0186] In step S104, the control unit 90 stops the first pump 63 for a second predetermined time T2 with the first on-off valve 66c in a closed state. This stabilizes the liquid level state in the humidifying fluid storage unit 61. Note that, in order to shorten the time until the liquid level state stabilizes, it is desirable to reduce the amount of change in the height of the liquid level when the amount of liquid in the humidifying fluid storage unit 61 changes by increasing the area of ​​the liquid level relative to the depth within the humidifying fluid storage unit 61.

[0187] In step S105, the control unit 90 acquires information on the liquid level in the humidification fluid storage unit 61 from the detection unit 61a. Then, in step S106, the control unit 90 determines whether the liquid level is higher than a first predetermined height H1. If the liquid level is higher than the first predetermined height H1, the flow ends.

[0188] When the liquid level is lower than the first predetermined height H1, the process proceeds to step S200. In step S200, the control unit 90 executes a subroutine for a concentration adjustment operation, which will be described later. When the subroutine for the concentration adjustment operation ends, the control unit 90 ends the flow.

[0189] Before the first recording after installation in the liquid ejection device 11, the humidification fluid L1a can be circulated inside the cap 51a by the circulation operation shown in Fig. 19. Then, the humidification chamber 55 in the cap 51a can be filled with the humidification fluid L1a.

[0190] When the liquid ejection device 11 records on the medium M, the medium M fed from the medium storage unit 16 shown in Fig. 1 travels through a transport path 19 toward the recording unit 20. The liquid ejection head 21 ejects liquid toward the medium M transported in a first transport direction Z1. As a result, characters, images, and the like are recorded on the medium M.

[0191] During recording, the cap 51a is in an open state, so that evaporation of moisture from the humidification fluid L1a from the humidification chamber 55 is promoted more than when the chamber is capped. Assuming that the environmental conditions such as temperature and humidity are the same, the higher the recording frequency and the longer the recording time, the more moisture evaporates from the humidification fluid L1a.

[0192] On the other hand, as shown in Fig. 4, during capping, the moisture that has evaporated from the humidifying fluid L1a and passed through the first moisture permeable membrane 54 humidifies the waste liquid L2 absorbed in the absorber 53. As a result, when the viscosity of the waste liquid L2 absorbed in the absorber 53 is high, the viscosity of the waste liquid L2 is adjusted by the moisture evaporated from the humidifying fluid L1a. The moisture evaporated from the humidifying fluid L1a and the waste liquid L2 with the adjusted viscosity can humidify the closed space SP more efficiently. Even during capping, the moisture of the humidifying fluid L1a evaporates little by little.

[0193] 4, when the liquid ejection head 21 is not ejecting liquid, the capping state is established in which the cap unit 51 contacts the nozzle surface 23 of the liquid ejection head 21. That is, after the cap unit 51 moves from the retracted position in the third direction D3 to the maintenance position, the head unit 24 moves from the recording position in the first direction D1 to the maintenance position. In this capping state, the cap 51a contacts the nozzle surface 23 of the liquid ejection head 21, forming a closed space SP in which the nozzles 22 are open.

[0194] As shown in Fig. 4, the humidification chamber 55 is filled with a humidification fluid L1a. The moisture evaporated from the humidification fluid L1a passes through the first moisture permeable film 54 and the absorber 53 together with moist air containing the moisture, and humidifies the closed space SP. This makes it possible to humidify the opening 22a of the nozzle 22. Furthermore, since the viscosity of the liquid in the nozzle 22 is suppressed, the occurrence of ejection defects can be prevented.

[0195] Furthermore, the liquid ejection device 11 periodically performs flushing, which is an ejection operation for ejecting droplets unrelated to printing from the nozzles 22 into the closed space SP in the cap 51a. Even during flushing, the cap 51a is kept in contact with the nozzle surface 23 of the liquid ejection head 21 so as to surround the nozzles 22, as shown in Fig. 4. Furthermore, the liquid ejection device 11 cleans the liquid ejection head 21 when it is time to clean it, and when a cleaning instruction is received from the user using the operation unit 15.

[0196] When flushing or cleaning is performed, the liquid discharged from the nozzles 22 of the liquid ejection head 21 adheres to the nozzle surface 23. Therefore, after flushing or cleaning, the liquid ejection device 11 performs wiping. As shown in FIG. 3, with the head unit 24 in the maintenance position, the wiper carriage 41 moves from the retracted position in the fifth direction D5 to the turning back position, whereby the wiper member 42 wipes the nozzle surface 23. As a result, liquid and dirt such as dust adhering to the nozzle surface 23 of the liquid ejection head 21 are removed.

[0197] The waste liquid L2 discharged from the nozzle 22 into the cap 51a by flushing or cleaning is collected in the waste liquid storage section 86 in the waste liquid box 110. That is, as shown in FIG. 5, the waste liquid collection mechanism 80 collects the waste liquid L2 discharged into the cap 51a by flushing or cleaning in the waste liquid storage section 86 of the waste liquid box 110 through the first waste liquid flow path 81a by the third pump 82. When collecting the waste liquid L2, the fourth pump 84 lowers the air pressure in the buffer chamber 83, so that the waste liquid L2 in the cap 51a easily flows into the buffer chamber 83, and the waste liquid L2 is less likely to remain in the cap 51a. In addition, the waste liquid L2 collected from the nozzle surface 23 into the wiper carriage 41 by wiping is also collected in the waste liquid storage section 86 in the waste liquid box 110 through the second waste liquid flow path 81b. Since the first moisture permeable membrane 54 in the cap 51a does not allow liquid to pass through, the waste liquid L2 does not flow into the humidification chamber 55 during flushing or cleaning.

[0198] 4, the closed space SP into which the nozzle 22 opens is humidified by the moisture contained in the humidification fluid L1a filled in the humidification chamber 55. This reduces the amount of moisture contained in the humidification fluid L1a filled in the humidification chamber 55. As a result, the concentration of the humidification fluid L1a filled in the humidification chamber 55 becomes higher than the concentration of the humidification fluid L1a in the humidification fluid storage portion 61.

[0199] As shown in FIG. 19, the first pump 63 is periodically driven to perform a circulation operation. That is, the humidification fluid L1a is circulated in the circulation path 62 in the circulation direction shown by the solid arrow in FIG. 19. The circulation operation can restore the amount of moisture contained in the humidification fluid L1a filled in the humidification chamber 55, that is, the moisture concentration of the humidification fluid L1a, to an appropriate concentration. The control unit 90 periodically performs the circulation operation by managing the time using a timer or the like. This makes it possible to make the concentration of the humidification fluid L1a throughout the circulation path 62 uniform at an appropriate timing. This makes it possible to prevent ejection defects caused by insufficient humidification of the opening of the nozzle 22.

[0200] Furthermore, when the sealing performance of the seal portion 56c of the cap 51a is reduced due to deterioration or fatigue caused by long-term use, or when the seal portion 56c is damaged or broken for some reason, the entire cap unit 51 or the cap 51a is replaced with a new one. Prior to this cap replacement, a cap replacement preparation operation is performed. Pressurized air is supplied from the pressurized air supply portion 67 into the cap 51a, thereby pushing out the humidified fluid L1a in the cap 51a and recovering it in the humidified fluid storage portion 61. Therefore, the loss of the humidified fluid L1a caused by the cap replacement is kept to a minimum.

[0201] After the cap replacement preparation operation is completed, the cap unit 51 or the cap 51a is replaced with a new one. After replacement, the above-mentioned circulation operation is performed, and the humidification chamber 55 in the new cap 51a is filled with the humidification fluid L1a. This humidifies the closed space SP surrounding the opening of the nozzle 22 when the replaced cap 51a comes into contact with the liquid ejection head 21, thereby preventing ejection defects caused by thickening of the liquid in the nozzle 22, etc.

[0202] The cap device 50 humidifies the closed space SP with the moisture contained in the humidifying fluid L1a filled in the humidifying chamber 55 and periodically performs a circulation operation, thereby reducing the volume of the humidifying fluid L1a contained in the humidifying fluid storage section 61 by the amount of evaporated moisture.

[0203] During the circulation operation, when the liquid level in the humidifying fluid storage section 61 is detected by the detection section 61a to be below a first predetermined height H1, it is determined that the concentration of the humidifying fluid L1a in the circulation path 62 has become higher than a predetermined concentration, and the concentration adjustment operation flow shown in Figure 18 is executed.

[0204] Next, the flow of the density adjustment operation executed by the control unit 90 will be described with reference to the flowchart shown in FIG. In step S201, the control unit 90 determines whether the first on-off valve 66c is open. If the first on-off valve 66c is open, the process proceeds to step S203. If the first on-off valve 66c is closed, the process proceeds to step S202, where the control unit 90 opens the first on-off valve 66c.

[0205] In step S203, the control unit 90 drives the first pump 63 for a third predetermined time T3 with the first on-off valve 66c in an open state. As a result, as shown in FIG. 19, the humidifying fluid L1a flows in the circulation path 62 in the direction of the solid arrow shown in FIG. 19. Then, the adjustment water L1b flows in the adjustment water supply flow path 66b in the direction of the dashed arrow shown in FIG. 19, and merges with the humidifying fluid L1a at the first junction 62c. Then, the humidifying fluid L1a and the adjustment water L1b that have merged become the humidifying fluid L1a whose concentration has been adjusted, and flows from the first junction 62c toward the cap 51a, flows in the circulation path 62 in the direction of the solid arrow shown in FIG. 19, and flows into the humidifying fluid storage unit 61. Then, the liquid level in the humidifying fluid storage unit 61 becomes higher than the liquid level before the concentration adjustment operation starts.

[0206] In step S204, the control unit 90 acquires information on the liquid level in the humidification fluid storage unit 61 from the detection unit 61a. Then, in step S205, the control unit 90 determines whether the liquid level is higher than the first predetermined height H1. If the liquid level is higher than the first predetermined height H1, the process proceeds to step S206. If the liquid level is lower than the first predetermined height H1, the process proceeds to step S207.

[0207] In step S206, the control unit 90 closes the first on-off valve 66c, and in S100, the process proceeds to a subroutine for the circulation operation shown in Fig. 17. When the control unit 90 ends the subroutine for the circulation operation, the flow ends.

[0208] As shown in Fig. 19, when the detection unit 61a detects that the liquid level in the humidifying fluid storage unit 61 is below the first predetermined height H1, the concentration adjustment operation shown in Fig. 18 is performed. In this case, the capping device 50 supplies the adjusted water L1b in the adjusted water storage unit 66a to the circulation path 62 until the liquid level is detected to be equal to or higher than the first predetermined height H1, with the third predetermined time being the upper limit. After performing the concentration adjustment operation, the capping device 50 causes the humidifying fluid L1a to flow in the circulation path 62 by performing the circulation operation shown in Fig. 17 again. As a result, after the evaporated moisture is replenished to the humidifying fluid L1a, the humidifying fluid L1a is agitated, and the concentration of the humidifying fluid L1a in the entire circulation path 62 can be made uniform.

[0209] In step S207, when the control unit 90 determines that the conditioned water L1b in the conditioned water storage unit 66a has run out, in step S208, the control unit 90 executes an conditioned water storage unit pre-exchange operation. That is, when the amount of conditioned water L1b in the conditioned water storage unit 66a reaches an amount at which it is determined that the conditioned water storage unit 66a needs to be replaced, the capping device 50 executes an conditioned water storage unit pre-exchange operation. When the control unit 90 finishes the conditioned water storage unit pre-exchange operation, the process proceeds to step S209.

[0210] In steps S203 to S205, the control unit 90 may drive the first pump 63 while acquiring information on the liquid level in the humidifying fluid storage unit 61 from the detection unit 61a with the first on-off valve 66c in an open state, and may stop the first pump 63 when the liquid level becomes higher than the first predetermined height H1. Then, when the third predetermined time T3 has elapsed since the first pump 63 was driven and the detection unit 61a detects that the liquid level is below the first predetermined height H1, the control unit 90 may determine in step S207 that the adjusting water L1b in the adjusting water storage unit 66a has run out.

[0211] In step S209, the control unit 90 notifies an error that the conditioned water L1b in the conditioned water storage unit 66a has run out by displaying information that the conditioned water L1b in the conditioned water storage unit 66a has run out on the display unit 15a of the operation unit 15. The user who has been notified of this error replaces the conditioned water storage unit 66a.

[0212] However, in this embodiment, the amount of the conditioned water L1b contained in the conditioned water storage section 66a is set so that the waste liquid storage section 86 becomes full with the waste liquid L2 before the conditioned water L1b contained in the conditioned water storage section 66a becomes empty (the end liquid level). Therefore, the above error notification does not occur in normal use.

[0213] In this embodiment, the waste liquid storage section 86 is set to be filled with the waste liquid L2 before it is determined that the adjusted water in the adjusted water storage section 66a has run out, and replacement of the waste liquid box 110 is prompted. That is, the amount of adjusted water before use stored in the adjusted water storage section 66a and the capacity at which the waste liquid storage section 86 is filled with the waste liquid L2 are set to satisfy such conditions. The amount of moisture that decreases from the humidifying fluid L1a per unit time (i.e., the adjusted water decrease rate V1) (milliliters / day) is estimated based on the maximum recording frequency and the longest total recording time assumed in normal use. In addition, the maximum amount of waste liquid generated per unit time (i.e., the waste liquid generation rate V2) (milliliters / day) assumed based on the frequency of flushing, cleaning, and wiping and the amount of liquid consumed per one time (amount of waste liquid) is estimated. If the waste liquid volume is F (milliliters), the time T (days) until the waste liquid storage section 86 is filled with the waste liquid L2 is calculated as T=F / V2. Furthermore, the remaining amount R of the conditioned water L1b after a time T has elapsed since the start of use of the conditioned water storage portion 66a is calculated by the formula R=G-V1*T, where G is the initial storage amount of the conditioned water L1b.

[0214] Therefore, the initial capacity G of the conditioned water storage section 66a is set so as to satisfy R=G-V1*F / V2>0. In other words, the initial capacity G of the conditioned water storage section 66a is set to an amount greater than V1*F / V2. For example, if the margin amount is α, the initial capacity G of the conditioned water storage section 66a is set to G=V1*F / V2+α. This ensures that conditioned water L1b remains in the conditioned water storage section 66a when the waste liquid storage section 86 becomes full of waste liquid L2, even if the cleaning frequency, etc. is slightly higher than normal.

[0215] For example, the above error will be reported only in the case of abnormal use, such as when the cleaning frequency is excessively higher than normal, or when the liquid ejection device 11 is stopped in an emergency and the cap 51a is left open for a long period of time, causing the rate at which the adjustment water L1b decreases to be excessively high.

[0216] The control unit 90 ends the flow of the concentration adjustment operation when it has completed the circulation operation in step S100 (FIG. 17) which is executed after the replenishment of the adjusting water has been completed (S206), or when it has notified of an error in step S209.

[0217] As described above, in normal cases, the waste liquid storage section 86 becomes full with the waste liquid L2 before the adjusted water L1b in the adjusted water storage section 66a becomes empty. When the control section 90 detects that the waste liquid storage section 86 is full with the waste liquid L2, it causes the display section 15a to display information that the waste liquid box 110 is full with the waste liquid and a message that prompts the user to replace the waste liquid box 110. The user who sees this message replaces the waste liquid box 110 with a new one. That is, the user removes the waste liquid box 110 that is full with the waste liquid L2 from the mounting section 100 by pulling it out in the direction opposite to the mounting direction A. Next, the new waste liquid box 110 is mounted on the mounting section 100 by pushing it in the mounting direction A.

[0218] The control unit 90 detects that a new waste liquid box 110 has been attached via the electrical connection between the board connection unit 105 and the connection terminal 117A of the circuit board 117. Then, the control unit 90 executes a circulation operation (FIG. 17) and a concentration adjustment operation (FIG. 18). When replacing the waste liquid box 110, the concentration adjustment operation (FIG. 18) may be executed first without executing the circulation operation.

[0219] As described above, the cap device 50 includes the cap 51a having the humidification chamber 55 and the first moisture permeable membrane 54, and the cap 51a can receive the liquid discharged from the nozzle 22 and humidify the nozzle 22. The humidification fluid L1a can be stirred and its concentration can be optimized by circulating the humidification fluid L1a in the circulation path 62 while replenishing the humidification fluid L1a with the moisture that has evaporated. This allows the humidification fluid L1a in the entire circulation path 62 to be maintained in a state suitable for humidifying the nozzle 22 of the liquid ejection head 21. When the humidification fluid L1a in the humidification fluid storage section 61 runs short, the adjustment water L1b is replenished from the adjustment water storage section 66a. The adjustment water storage section 66a is integrated into the waste liquid box 110, and is replaced with a new one together with the waste liquid storage section 86 when the waste liquid box 110 becomes full of the waste liquid L2 and is replaced with a new one. The user can perform only the replacement work of the waste liquid box 110 without being aware of the replaceable adjustment water storage section 66a. Therefore, even if the adjustment water storage section 66a that stores the adjustment water L1b is configured to be replaceable, the number of boxes and cartridges to be replaced does not increase, and the replacement work hardly increases.

[0220] The effects of this embodiment will be described. (1) The waste liquid box 110 is detachably attached to the mounting part 100 having a waste liquid discharge part 103, which is an example of a discharge part that discharges the waste liquid L2, and a liquid introduction part 104. The waste liquid box 110 includes a waste liquid introduction part 115 that is connected to the waste liquid discharge part 103 when the waste liquid box 110 is mounted to the mounting part 100, and a waste liquid storage part 86 that can store the waste liquid L2 discharged from the waste liquid discharge part 103. Furthermore, the waste liquid box 110 includes a liquid discharge part 116 that is connected to the liquid introduction part 104 when the waste liquid box 110 is mounted to the mounting part 100, and an adjustment water storage part 66a that is an example of a liquid storage part that stores adjustment water L1b, which is an example of a liquid to be led to the liquid introduction part 104. The adjustment water L1b is a liquid containing water for humidifying the cap 51a, which is an example of a part to be humidified.

[0221] According to this configuration, the waste liquid box 110 equipped with the waste liquid storage section 86 is provided with the adjusted water storage section 66a that stores the adjusted water L1b including water for humidification, so there is no need to provide a separate liquid storage body such as a box or cartridge dedicated to humidification that stores the liquid for humidification in addition to the waste liquid box 110 that stores the waste liquid L2. Also, for the user, there is no additional effort required to purchase or replace an extra adjusted water box as a consumable item other than the liquid supply source 31 that stores the ink required for printing.

[0222] (2) The conditioned water L1b is a liquid containing water and a preservative. With this configuration, the conditioned water L1b containing the water for humidification can be used for a long period of time. (3) The amount of the adjusting water L1b contained in the adjusting water storage unit 66a is set to a liquid amount that causes the waste liquid storage unit 86 to first become full with the waste liquid L2 before the adjusting water L1b contained in the adjusting water storage unit 66a runs out. This configuration makes it possible to prevent the adjusting water L1b containing the water for humidification from running out first.

[0223] (4) A first cover 112 is provided to cover the waste liquid storage section 86. The waste liquid storage section 86 stores an absorbing member 120 capable of absorbing the waste liquid L2. When the waste liquid box 110 is attached to the attachment section 100, the upper surface of the absorbing member 120 is covered by the first cover 112. This configuration can prevent the waste liquid L2 absorbed by the absorbing member 120 from leaking out.

[0224] (5) The conditioned water storage portion 66a is an conditioned water pack 68, which is an example of a bag that stores the conditioned water L1b. According to this configuration, the conditioned water storage portion 66a can be easily provided. (6) A second cover 113 is provided to cover the conditioned water storage section 66a. When the waste liquid box 110 is attached to the attachment section 100, the lower surface of the conditioned water storage section 66a is covered by the second cover 113. With this configuration, the conditioned water pack 68 prevents the conditioned water L1b from leaking, so the lower surface can be covered. Therefore, the waste liquid storage section 86 and the conditioned water storage section 66a can be easily separated and stored in the waste liquid box 110 in a state where liquid leakage is unlikely.

[0225] (7) The mounting unit 100 has a board connection portion 105. The waste liquid box 110 includes a circuit board 117 having a connection terminal 117A that is electrically connected to the board connection portion 105 when the waste liquid box 110 is mounted on the mounting unit 100. In a position in which the waste liquid box 110 is mounted on the mounting unit 100, the connection terminal 117A of the circuit board 117 is provided at a position higher than the center of the waste liquid introduction portion 115. This configuration can prevent the waste liquid L2 from adhering to the connection terminal 117A.

[0226] (8) When the direction in which waste liquid box 110 is mounted in mounting portion 100 is defined as mounting direction A, waste liquid inlet portion 115 is provided on one side and circuit board 117 is provided on the other side in width direction W intersecting with mounting direction A. This configuration can prevent waste liquid L2 from adhering to connection terminal 117A.

[0227] (9) The liquid outlet 116 is provided between the waste liquid inlet 115 and the circuit board 117 in the width direction W, and is provided at a position lower than the circuit board 117 in the vertical direction Z. This configuration can prevent liquids such as the waste liquid L2 and the adjusted water L1b from adhering to the connection terminal 117A.

[0228] (10) The liquid ejection device 11 includes a liquid ejection head 21, which is an example of a liquid ejection section that ejects liquid (e.g., ink) supplied from a liquid supply source 31 from a nozzle 22, and a cap 51a that can form a closed space SP in which the nozzle 22 opens upon contact with the liquid ejection head 21. The liquid ejection device 11 further includes a mounting section 100 to which a waste liquid box 110 is detachably mounted, a supply flow path 62a that communicates between the liquid introduction section 104 and the cap 51a, and a first pump 63, which is an example of a first liquid delivery section that delivers the adjustment water L1b in the waste liquid box 110 to the cap 51a. With this configuration, the adjustment water L1b containing water can be used to humidify the nozzle 22.

[0229] (11) The liquid ejection device 11 includes a first waste liquid flow path 81a that communicates the cap 51a with the waste liquid discharge portion 103, and a third pump 82 that is an example of a second liquid delivery portion that delivers the waste liquid L2 discharged from the liquid ejection head 21 into the cap 51a to the waste liquid discharge portion 103. With this configuration, the cap 51a for humidification can also be used as the cap 51a for receiving the waste liquid L2.

[0230] (12) By replenishing the humidification fluid L1a to the cap 51a, the frequency of cleaning and powerful cleaning can be reduced, and the capacity of the waste liquid storage section 86 can be reduced. Therefore, the size of the waste liquid box 110 does not increase significantly, even though the adjustment water storage section 66a is integrally accommodated. In other words, a small waste liquid box 110 can be provided, even though the adjustment water storage section 66a is integrally accommodated.

[0231] Second embodiment Next, a second embodiment will be described with reference to Figs. 20 and 21. In this embodiment, the caps in the first embodiment are divided into two types: a discharge cap and a moisturizing cap. The discharge cap is a cap dedicated to receiving waste liquid that receives waste liquid discharged from the nozzles 22 of the liquid ejection head 21 during maintenance, and the moisturizing cap is a cap dedicated to moisturizing the nozzles 22 of the liquid ejection head 21 to prevent clogging of the nozzles 22 when the head is not in use. Note that in this embodiment, the configuration is the same as that of the first embodiment, except that the caps are divided into two types: a moisturizing cap and a discharge cap.

[0232] The liquid ejection device 11 includes a cap unit 51 shown in FIG. 20. The cap unit 51 includes a moisture retention cap 151 as an example of a humidified portion, and a discharge cap 152. The moisture retention cap 151 and the discharge cap 152 are substantially the same in shape and size as the cap 51a of the first embodiment. The moisture retention cap 151 and the discharge cap 152 are configured to be able to move back and forth in the first transport direction Z1 as a unit. For example, the moisture retention cap 151 and the discharge cap 152 are fixed to the upper surface of a common slider (not shown), and the slider moves back and forth in the first transport direction Z1 by the power of a drive source (both not shown) via a power transmission mechanism, so that the moisture retention cap 151 and the discharge cap 152 can be located at a retracted position shown in FIG. 20 and a maintenance position shown by a two-dot chain line in FIG. 20. The moisture retention cap 151 and the discharge cap 152 may be configured to be able to move individually.

[0233] During non-recording, the moisturizing cap 151 is disposed at a maintenance position facing the nozzle surface 23 of the liquid ejection head 21. During maintenance including cleaning and flushing, the discharge cap 152 is disposed at a maintenance position facing the nozzle surface 23 of the liquid ejection head 21. In this state, the liquid ejection head 21 moves from the recording position shown by the solid line in FIG. 20 to the maintenance position shown by the two-dot chain line in FIG. 20, whereby the nozzle surface 23 of the liquid ejection head 21 is capped by the moisturizing cap 151 or the discharge cap 152. In this capping state, the moisturizing cap 151 or the discharge cap 152 comes into contact with the nozzle surface 23 of the liquid ejection head 21 to form a closed space SP in which the nozzles 22 are open. In more detail, the moisturizing cap 151 is configured to be capable of forming a closed space SP in which the nozzles 22 are open when it comes into contact with the liquid ejection head 21. Moreover, the discharge cap 152 is configured to be capable of forming a closed space SP in which the nozzles 22 are open when it comes into contact with the liquid ejection head 21.

[0234] 20, a humidification chamber 55 and a first moisture permeable film 54 covering the humidification chamber 55 are disposed on the inner bottom of the moisture retention cap 151. Therefore, when capped with the moisture retention cap 151, the closed space SP is humidified and the nozzles 22 are moistened. As a result, clogging of the nozzles 22 caused by thickening of the liquid in the nozzles 22 during non-recording or while the liquid ejection device 11 is powered off can be suppressed.

[0235] 20, the discharge cap 152 includes therein an absorbent 53 and a regulating member 52 that covers the absorbent 53. The regulating member 52 and the absorbent 53 have the same functions as those of the cap 51a of the first embodiment. The moisture retention cap 151 may include one or both of the absorbent 53 and the regulating member 52. In this case, the liquid dripping from the nozzle 22 can be absorbed by the absorbent 53, and the regulating member 52 can prevent the absorbent 53 from floating up or coming off.

[0236] 20 and 21, a supply flow path 62a and a recovery flow path 62b are connected to the humidification chamber 55 of the moisture retention cap 151. In addition, a first atmosphere communication passage 58a and a first waste liquid flow path 81a are connected to the discharge cap 152.

[0237] 21, the humidification chamber 55 of the moisturizing cap 151 is connected to the moisturizing fluid storage section 61 through a supply flow path 62a and a recovery flow path 62b that constitute the circulation path 62. The cap device 50 includes a supply flow path 62a that communicates between the liquid introduction section 104 (see FIG. 6) and the moisturizing cap 151, and a first pump 63 that is an example of a first liquid delivery section that delivers the adjusted water L1b, which is a liquid in an adjusted water storage section 66a that is an example of a liquid storage section, to the cap 51a.

[0238] When not recording, the moisturizing cap 151 is placed in the maintenance position shown in Fig. 21, and the head unit 24 is placed in the maintenance position shown by the two-dot chain lines in Figs. 20 and 21. As a result, the liquid ejection head 21 is capped by the moisturizing cap 151. In this capping state, a closed space SP is formed in which the nozzles 22 are open. The closed space SP is humidified by the water vapor contained in the moisturizing fluid L1a from the humidifying chamber 55, thereby moisturizing the nozzles 22.

[0239] Since the humidifying fluid L1a is circulated at a predetermined timing, the concentration of the humidifying fluid L1a in the humidifying chamber 55 is optimized. In addition, when the humidifying fluid L1a in the humidifying fluid storage unit 61 is insufficient due to a loss in volume caused by evaporation of moisture, the first pump 63 is driven with the first opening / closing valve 66c open. As a result, the adjusted water L1b is replenished from the adjusted water storage unit 66a in the waste liquid box 110 through the adjusted water supply flow path 66b and the circulation path 62 into the humidifying fluid storage unit 61. Therefore, the humidifying fluid L1a with an optimized concentration is supplied to the humidifying chamber 55. Therefore, in the capping state of the moisturizing cap 151, the nozzle 22 opening into the closed space SP is appropriately moisturized.

[0240] As shown in FIG. 21, the capping device 50 is provided with a first waste liquid flow path 81a that connects between a waste liquid discharge section 103 (see FIG. 6) as an example of a discharge section of the mounting section 100 and the discharge cap 152, and a third pump 82 as an example of a second liquid delivery section that delivers the waste liquid L2 discharged from the liquid ejection head 21 into the discharge cap 152 to the waste liquid discharge section 103.

[0241] During flushing and cleaning, the discharge cap 152 is placed at the maintenance position, and the head unit 24 moves from the recording position shown by the solid lines in Figures 20 and 21 to the maintenance position shown by the two-dot chain lines in the same figures. As a result, the liquid ejection head 21 is capped by the discharge cap 152. In this capping state, a closed space SP is formed in which the nozzles 22 are open. The liquid ejected or discharged from the nozzles 22 of the liquid ejection head 21 is received by the discharge cap 152 as waste liquid L2. By driving the third pump 82, the waste liquid L2 is collected from the discharge cap 152 through the inlet portion 86b into the waste liquid storage portion 86 in the waste liquid box 110.

[0242] According to the second embodiment, in addition to obtaining the effects (1) to (12) of the first embodiment, the following effects are obtained. (13) The liquid ejection device 11 includes a discharge cap 152 capable of contacting the liquid ejection head 21 to form a closed space SP in which the nozzle 22 opens, a first waste liquid flow path 81a that connects the discharge cap 152 with the waste liquid discharge section 103, and a third pump 82 that is an example of a second liquid delivery section that delivers the waste liquid L2 discharged from the liquid ejection head 21 into the discharge cap 152 to the waste liquid discharge section 103. According to this configuration, the humidification cap 151 and the discharge cap 152 that receives the waste liquid L2 are provided independently of each other, so that a configuration suitable for each function can be adopted.

[0243] This embodiment can be modified as follows: This embodiment and the following modifications can be combined with each other to the extent that there is no technical contradiction. Although the adjusted water L1b is a liquid containing water and a preservative, it does not have to contain a preservative. For example, the adjusted water L1b may be a liquid containing additives other than water and a preservative. The adjusted water L1b may also be a liquid consisting of water only.

[0244] The waste liquid L2 was waste ink made of ink discharged from the nozzle 22 of the liquid ejection head 21 for maintenance, but it may be waste liquid other than ink. For example, it may be a pre-treatment liquid or a post-treatment liquid discharged from the nozzle 22 of the liquid ejection head 21 toward the medium M. The waste liquid L2 may also be a cleaning liquid for cleaning the nozzle 22 of the liquid ejection head 21. The cleaning liquid is a liquid that dissolves ink by being sprayed against the nozzle surface 23 of the liquid ejection head 21 with a cleaning nozzle or the like. In this way, the waste liquid L2 may be a liquid that is generated as a result of maintenance of the liquid ejection head 21. The cleaning liquid used for cleaning may be stored as the waste liquid L2 in the waste liquid storage section 86 of the waste liquid box 110. The liquid storage body may have both a waste liquid storage section that stores waste ink and a waste liquid storage section that stores waste cleaning liquid. Such a waste liquid storage body may also have a liquid storage section that stores a liquid including water for humidification (for example, the adjustment water L1b).

[0245] The liquid storage section may be a tank chamber provided in the liquid storage body instead of a liquid pack such as the adjusted water pack 68. For example, it may be an adjusted water tank chamber, and a vent hole may be provided to connect the chamber to the atmosphere. For example, a moisture-permeable membrane may be provided in the vent hole to prevent the adjusted water from leaking from the vent hole.

[0246] Although the adjusted water storage unit 66a is given as an example of a liquid storage unit, the liquid storage unit contained in the waste liquid box 110 as an example of a liquid container together with the waste liquid storage unit 86 is not limited to adjusted water for adjusting the concentration of the humidifying fluid L1a that humidifies the liquid ejection head 21. For example, the liquid may be a replenishment humidifying fluid that replenishes the humidifying fluid storage unit 61 with the humidifying fluid L1a. For example, when the waste liquid box is replaced, the liquid storage unit may also be replaced at the same time, and the humidifying fluid L1a may be replenished from the new liquid storage unit to the humidifying fluid storage unit 61.

[0247] A plurality of liquid storage sections may be stored in the waste liquid box 110, which is an example of a liquid storage body. In this case, the plurality of liquid storage sections may store the same type of liquid, or may store different types of liquid. In this case, the liquid may be any liquid that contains water for humidification.

[0248] In the posture when the waste liquid box 110 is attached to the mounting part 100, the waste liquid box 110 may be configured so that the adjustment water storage section 66a, which is an example of a liquid storage section, is arranged on the upper side and the waste liquid storage section 86 is arranged on the lower side. Also, in the waste liquid box 110 in the posture when it is attached to the mounting part 100, the adjustment water storage section 66a and the waste liquid storage section 86 may be arranged side by side in the horizontal direction. With this configuration, it is possible to realize a thin waste liquid box 110. In this manner, the layout of the adjustment water storage section 66a and the waste liquid storage section 86 in the waste liquid box 110 may be set arbitrarily.

[0249] The adjusted water L1b is not limited to a liquid having a function of adjusting the concentration of the humidifying fluid L1a, but may be adjusted water that adjusts the components of the humidifying fluid L1a. For example, if the humidifying fluid L1a contains a component that evaporates or volatilizes together with water, the adjusted water L1b may be adjusted water that contains this component.

[0250] The capping device 50 may have only one cap 51a instead of a configuration having a plurality of caps 51a. For example, a configuration may be provided with one cap for the head unit 24. Also, there may be one cap that is capable of contacting a plurality of unit ejection heads 21a to form one closed space SP.

[0251] In the above embodiment, the flow path of the humidifying chamber 55 is formed in a maze shape with one straight path from the inlet 55a to the outlet 55b, but it may be two-way or three-way. It is sufficient that the flow path is connected from the inlet 55a to the outlet 55b.

[0252] The arrangement of the unit discharge heads 21a constituting the liquid discharge head 21 can be changed as appropriate. It is not limited to the configuration in which the unit discharge heads 21a are arranged diagonally as in the above embodiment, but may be, for example, a configuration in which the unit discharge heads 21a are arranged in two rows at a fixed interval in the width direction X, and are arranged in a staggered arrangement in which the positions of the rows are shifted in the width direction by half the interval.

[0253] In the above embodiment, the supply flow passage 62a in the circulation path 62 is provided with the adjusted water supply unit 66 capable of supplying the adjusted water L1b, but the recovery flow passage 62b in the circulation path 62 may be provided with the adjusted water supply unit 66. In that case, the capping device 50 may further include a pump for supplying the adjusted water L1b to the recovery flow passage 62b.

[0254] The capping device 50 may have a second detection unit that detects the amount of the adjusted water L1b in the adjusted water storage unit 66a. Based on the detection result of the second detection unit, the control unit 90 may determine whether the amount of the adjusted water L1b in the adjusted water storage unit 66a has reached an amount that requires replacement of the adjusted water storage unit 66a.

[0255] The waste liquid box 110 may be configured so that the adjustment water L1b in the adjustment water storage section 66a can be replenished. Also, the capping device 50 may be configured so that the humidification fluid storage section 61 can be replaced.

[0256] The timing at which the cyclical action is performed may be changed by an administrator or a user. The first, second, third, and fourth predetermined times T1, T2, T3, and T4 do not have to be constant. The values ​​may be changed according to the temperature and humidity environment. Also, the values ​​may be changed by an administrator or a user.

[0257] The humidified portion is not limited to a cap such as the cap 51a or the moisturizing cap 151. For example, the humidified portion may be the medium storage portion 16 in which the medium M is stored. For example, the medium storage portion 16 may be humidified in order to moisturize the medium M. This can suppress variation in curl of the medium M after recording, which is caused by variation in the moisture content of the medium M before recording due to a change in humidity inside the main body portion 12 of the liquid ejection device 11.

[0258] The liquid ejection device may be an inkjet printing device. The printing device may include an attachment part 100, and a waste liquid box 110 as a liquid container attached to the attachment part may house both the waste liquid container 86 and the adjusted water container 66a, which is an example of a liquid container.

[0259] The capping device 50 may be provided in a liquid ejection device that ejects liquid vertically from the liquid ejection head 21 toward the medium M. In the cap 51a, the seal portion 56c that comes into close contact with the nozzle surface 23 of the liquid ejection head 21 during capping, the absorber 53, the first moisture permeable membrane 54, and the humidification chamber 55 may be provided in a horizontal state. That is, the cap 51a of this embodiment may be provided in a horizontal state.

[0260] The capping device 50 may be provided in the liquid ejection device 11, which is a serial type inkjet printer that performs printing by ejecting liquid toward the medium M from a liquid ejection head supported by a carriage that moves back and forth in the width direction X. When the carriage that moves back and forth moves in the width direction X from an ejection area where printing is performed on the medium M to a maintenance area outside the ejection area for maintenance, the cap of the capping device 50 arranged in the maintenance area may cap the nozzle surface of the liquid ejection head. In this case, the capping device 50 may be configured such that, when the carriage moves to the maintenance area and the liquid ejection head is located at the maintenance position, the cap moves in a direction approaching the nozzle surface of the liquid ejection head and the cap comes into close contact with the nozzle surface, thereby performing capping. A humidification chamber 55 may be provided in the cap that can form a closed space in which the nozzles are open by contacting the nozzle surface of the liquid ejection head when not recording. Furthermore, the capping device 50 includes a humidification fluid circulation mechanism 60 that supplies humidification fluid L1a to the humidification chamber 55. The humidified fluid circulation mechanism 60 includes an attachment portion 100, an adjustment water storage portion 66a which is an example of a liquid storage portion, a waste liquid storage portion 86, etc. Then, both the waste liquid storage portion 86 and the adjustment water storage portion 66a are stored in a waste liquid box 110 which is an example of a liquid storage body that is detachably attached to the attachment portion 100. As a result, even in a serial type liquid ejection device, there is no need to separately provide an adjustment water box (adjustment water cartridge) in addition to the waste liquid box 110. In addition, for the user, there is no additional effort required for purchasing and replacing an extra adjustment water box as a consumable item other than the liquid supply source 31 which stores the ink required for printing.

[0261] In the liquid ejection device, the adjustment water storage section 66a may be eliminated, and instead the humidification fluid storage section 61 may be provided in the waste liquid box 110. In other words, by providing the humidification fluid storage section 61 in the waste liquid box 110, it may be configured so that it can be attached to and detached from the attachment section 100 together with the waste liquid storage section 86.

[0262] Furthermore, the waste liquid box 110 may be provided with three types of storage sections: the waste liquid storage section 86, the conditioned water storage section 66a, and the humidification fluid storage section 61. The liquid ejection device 11 may be a liquid ejection device that ejects liquid other than ink. The state of the liquid ejected from the liquid ejection device as minute droplets includes granular, teardrop, and thread-like tails. The liquid here may be any material that can be ejected from the liquid ejection device. For example, the liquid may be any state in which a substance is in a liquid phase, and includes fluids such as high or low viscosity liquids, sols, gel water, other inorganic solvents, organic solvents, solutions, liquid resins, liquid metals, and metal melts. The liquid includes not only liquids as one state of matter, but also particles of functional materials made of solids such as pigments and metal particles dissolved, dispersed, or mixed in a solvent. Representative examples of liquids include inks and liquid crystals as described in the above embodiments.

[0263] The technical ideas and effects obtained from the above-described embodiment and modified examples will be described below. (A) The liquid container is a liquid container that is removably attached to an attachment portion having a discharge portion for discharging waste liquid and a liquid introduction portion, and includes a waste liquid introduction portion that is connected to the discharge portion when the liquid container is attached to the attachment portion, a waste liquid storage portion that can store waste liquid discharged from the discharge portion, a liquid discharge portion that is connected to the liquid introduction portion when the liquid container is attached to the attachment portion, and a liquid storage portion that stores liquid that is discharged to the liquid introduction portion, wherein the liquid is a liquid containing water for humidifying the portion to be humidified.

[0264] According to this configuration, a liquid container having a waste liquid storage section is provided with a liquid storage section that stores liquid including water for humidification, so there is no need to provide a separate liquid container that stores liquid for humidification in addition to the liquid container that stores waste liquid.

[0265] (B) In the liquid container, the liquid may be a liquid containing water and a preservative. With this configuration, the liquid containing humidifying water can be used for a long period of time. (C) In the above liquid container, the amount of liquid contained in the liquid storage section may be set to an amount of liquid that will cause the waste liquid storage section to become full with waste liquid before the liquid contained in the liquid storage section runs out.

[0266] According to this configuration, it is possible to prevent the liquid containing humidification water from running out first. (D) The above liquid container may include a first cover that covers the waste liquid storage section, the waste liquid storage section may contain an absorbent member capable of absorbing waste liquid, and when the liquid container is attached to the mounting section, the upper surface of the absorbent member may be covered by the first cover.

[0267] According to this configuration, it is possible to prevent the waste liquid absorbed in the absorbing member from leaking out. (E) In the above liquid container, the liquid storage section may be a bag that stores the liquid. With this configuration, the liquid storage section can be easily provided.

[0268] (F) The above liquid container may include a second cover that covers the liquid storage portion, and when the liquid container is attached to the attachment portion, the lower surface of the liquid storage portion may be covered by the second cover.

[0269] According to this configuration, the bag prevents liquid from leaking, and the bottom surface can be covered. Therefore, the waste liquid storage section and the liquid storage section can be easily separated and stored in the liquid storage body in a state where liquid leakage is unlikely to occur.

[0270] (G) In the above liquid container, the mounting portion has a board connection portion, and is equipped with a circuit board having a connection terminal that is electrically connected to the board connection portion when the liquid container is mounted on the mounting portion, and when the liquid container is in a position where it is mounted on the mounting portion, the connection terminal of the circuit board may be located at a position higher than the center of the waste liquid inlet portion.

[0271] This configuration can prevent the waste liquid from adhering to the connection terminals. (H) In the above liquid container, when the direction in which the liquid container is mounted to the mounting portion is defined as the mounting direction, in a width direction intersecting the mounting direction, the waste liquid introduction portion may be provided on one side and the circuit board may be provided on the other side.

[0272] This configuration can prevent the waste liquid from adhering to the connection terminals. (I) In the above liquid container, the liquid outlet portion may be provided between the waste liquid inlet portion and the circuit board in the width direction, and may be provided at a position lower than the circuit board in the vertical direction.

[0273] This configuration can prevent liquid from adhering to the connection terminals. (J) A liquid ejection device includes a liquid ejection section that ejects liquid supplied from a liquid supply source from a nozzle, a cap as the humidified section that can contact the liquid ejection section to form a closed space in which the nozzle opens, the attachment section to which the liquid container is detachably attached, a supply flow path that communicates with the liquid introduction section and the cap, and a first liquid delivery section that delivers the liquid in the liquid container to the cap.

[0274] According to this configuration, a liquid including water can be used to humidify the nozzle. (K) The above liquid ejection device may further include a waste liquid flow path that connects the cap and the discharge section, and a second liquid delivery section that delivers waste liquid discharged from the liquid ejection section into the cap to the discharge section.

[0275] According to this configuration, the humidifying cap can also be used as a cap for receiving waste liquid. (L) The above liquid ejection device may further include a discharge cap capable of contacting the liquid ejection portion to form a closed space in which the nozzle opens, a waste liquid flow path connecting the discharge cap and the ejection portion, and a second liquid delivery portion that delivers waste liquid discharged from the liquid ejection portion into the ejection cap to the ejection portion.

[0276] According to this configuration, the cap for humidification and the cap for receiving waste liquid are provided independently, so that a configuration suitable for each function can be adopted. [Explanation of symbols]

[0277] 11...liquid ejection device, 12...main body, 13...image reading unit, 14...automatic feed unit, 15...operation unit, 15a...display unit, 16...medium storage unit, 17...mounting unit, 17a...mounting surface, 19...transport path, 20...recording unit, 21...liquid ejection head, 21a...unit ejection head, 21b...nozzle row, 22...nozzle, 22a...opening, 23...nozzle surface, 24...head unit, 25...support unit, 30...liquid supply mechanism, 31...liquid supply source, 32...subtank, 33...pump, 34...liquid supply path, 35...supply flow path, 36...recovery flow path, 40...wiper device, 41...wiper carriage, 42... Wiper member, 43...waste liquid outlet, 50...cap device, 51...cap unit, 51a...unit cap (cap) as an example of a humidified portion, 52...regulating member, 53...absorber, 54...first moisture permeable membrane, 54a...communicating portion, 55...humidification chamber, 55a...inlet, 55b...outlet, 55c...pipe portion, 55d...groove, 55e...rib, 55f...flow path, 56...case, 56a...atmosphere communication hole, 56b...discharge hole, 56c...seal portion, 57...recess, 58...atmosphere release mechanism, 58a...first atmosphere communication passage, 58b...third opening / closing valve, 59...holding portion, 60...humidified fluid circulation mechanism, 61...humidified fluid storage portion, 61a...detection portion, 61b...first electrode, 61c...second electrode, 61d...second atmosphere communication passage, 61e...second moisture permeable membrane, 61f...inlet portion, 61g...outlet portion, 62...circulation path, 62a...supply flow path, 62b...recovery flow path, 62c...first junction portion, 62d...clamp portion, 63...first pump as an example of a first liquid delivery portion, 64...first check valve, 65...pressure regulating valve, 66...adjusted water supply portion, 66a...adjusted water storage portion as an example of a liquid storage portion, 66b...adjusted water supply flow path, 66c...first opening / closing valve, 66d...second check valve, 66e...second junction portion, 66f...outlet portion, 66G...storage chamber, 67...pressurized air Supply unit, 67a...pressurized air supply path, 67b...second opening and closing valve, 67c...second pump, 68...humidification fluid pack, 68a...outflow portion, 69...clamp, 80...waste liquid recovery mechanism, 81...waste liquid recovery path, 81a...first waste liquid flow path as an example of a waste liquid flow path, 81b...second waste liquid flow path, 82...third pump as an example of a second liquid delivery unit, 83...buffer chamber, 84...fourth pump, 85...third atmosphere communication passage, 86...waste liquid storage unit, 86b...inflow portion, 86A...waste liquid chamber, 90...control unit, 91 detector group, 94...interface unit, 95...CPU, 96...memory, 97...control circuit, 98...drive circuit,99...computer, 100...mounting section, 101...mounting section main body, 102...positioning pin, 103...waste liquid discharge section as an example of a discharge section, 104...liquid introduction section, 105...substrate connection section, 110...waste liquid box as an example of a liquid container, 110A...mounting surface, 111...box main body, 111A...first opening, 111B...first storage chamber, 111C...second opening, 111D...second storage chamber, 11 1E...partition wall, 111F...partition plate, 111G...guide plate, 111H...board mounting portion, 112...first cover, 112A...vent hole, 113...second cover, 115...waste liquid inlet portion, 115A...waste liquid inlet tube, 116...liquid outlet portion, 116A...outlet port, 117...circuit board, 117A...connection terminal, 118...handle, 120...absorption member, 121...holding member, 121A...tube insertion hole, 122...waste liquid inlet chamber , 123...hole, 124...moisture permeable membrane, 125...groove, 125A...waste liquid flow path, 126...groove, 126A...waste liquid flow path, 127...notched hole, 131-133...screw, 151...moisture retention cap as an example of a humidified part, 152...discharge cap, θ1...first predetermined angle, θ2...second predetermined angle, D1...first direction, D2...second direction, D3...third direction, D4...fourth direction, D5...fifth direction, D6...sixth direction direction, H1...first predetermined height, H2...second predetermined height, L1a...humidification fluid, L1b...adjusted water which is an example of liquid, L2...waste liquid, M...medium, P1...first predetermined pitch, SP...closed space, T1...first predetermined time, T2...second predetermined time, T3...third predetermined time, T4...fourth predetermined time, X...width direction, Y...depth direction, Y1...discharge direction, Z1...first conveying direction, Z...vertical direction, A...mounting direction, W...width direction.

Claims

1. A liquid container that is detachably attached to a mounting part having a discharge part for discharging waste liquid and a liquid introduction part, a waste liquid introduction section that is connected to the discharge section when the liquid container is attached to the attachment section; a waste liquid storage section capable of storing the waste liquid discharged from the discharge section; a liquid outlet portion that is connected to the liquid inlet portion when the liquid container is attached to the attachment portion; a liquid storage section that stores the liquid introduced into the liquid introduction section; A circuit board having a connection terminal, The mounting portion has a board connection portion, the connection terminal is electrically connected to the board connection portion when the liquid container is attached to the attachment portion, When the liquid container is attached to the attachment portion, the connection terminal of the circuit board is provided at a position higher than a center of the waste liquid introduction portion, The liquid container is characterized in that the liquid contains water for humidifying a portion to be humidified.

2. When the direction in which the liquid container is attached to the attachment portion is defined as an attachment direction, 2. The liquid container according to claim 1, wherein the waste liquid introduction portion is provided on one side and the circuit board is provided on the other side in a width direction intersecting with the mounting direction.

3. 3. The liquid container according to claim 2, wherein the liquid outlet portion is provided between the waste liquid inlet portion and the circuit board in the width direction and at a position lower than the circuit board in the vertical direction.

4. 4. The liquid container according to claim 1, wherein the liquid contains water and a preservative.

5. A liquid container according to any one of claims 1 to 4, characterized in that the amount of liquid contained in the liquid storage section is set to an amount of liquid such that the waste liquid storage section becomes filled with waste liquid before the liquid contained in the liquid storage section runs out.

6. a first cover for covering the waste liquid storage section; The waste liquid storage section stores an absorbent member capable of absorbing waste liquid, 6. The liquid container according to claim 1, wherein an upper surface of the absorbing member is covered by the first cover when the liquid container is in a position where it is attached to the attachment portion.

7. 7. The liquid container according to claim 1, wherein the liquid storage portion is a bag that stores the liquid.

8. a second cover for covering the liquid storage portion; The liquid container according to claim 7 , wherein, in a position where the liquid container is attached to the attachment portion, a lower surface of the liquid container portion is covered by the second cover.

9. a liquid ejection unit that ejects liquid supplied from a liquid supply source from a nozzle; a cap as a humidified part capable of contacting the liquid ejection part to form a closed space in which the nozzle is open; The mounting portion to which the liquid container according to claim 1 is detachably mounted; a supply flow path that communicates the liquid introduction portion and the cap; a first liquid delivery section that delivers the liquid in the liquid container to the cap.

10. a waste liquid flow path that communicates the cap and the discharge portion; The liquid ejection device according to claim 9 , further comprising: a second liquid delivery section that delivers waste liquid discharged from the liquid ejection section into the cap to the discharge section.

11. a discharge cap capable of contacting the liquid discharge portion to form a closed space in which the nozzle is open; a waste liquid flow path that communicates the drain cap and the drain portion; The liquid ejection device according to claim 9 , further comprising: a second liquid delivery section that delivers waste liquid discharged from the liquid ejection section into the drain cap to the drain section.

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