Liquid storage unit, liquid flow mechanism, and liquid discharge apparatus

Abstract

The invention provides a liquid storage part, a liquid flow mechanism and a liquid ejection device, which can reduce the risk that liquid seeps to a moisture permeable film. The liquid storage part is provided with: a storage body for storing the discharge liquid and the moisturizing liquid; and a moisture-permeable film attached to the storage body, the moisture-permeable film dividing the interior of the storage body into a discharge liquid chamber, which is a space for storing the discharge liquid, and a moisturizing liquid chamber, which is a space for storing the moisturizing liquid, the storage body stores the discharge liquid and the moisturizing liquid such that the liquid level of the discharge liquid stored in the discharge liquid chamber and the liquid level of the moisturizing liquid stored in the moisturizing liquid chamber are positioned below the upper end of the moisture permeable film.

Description

Technical Field

[0001] The present invention relates to a liquid storage part, a liquid flow mechanism and a liquid ejection device. Background Art

[0002] Patent Document 1 describes a liquid ejection device that stores ejection liquid and moisturizing liquid in a state separated by a moisture permeable membrane. In this liquid ejection device, water contained in the moisturizing liquid is supplied to the ejection liquid through the moisture permeable membrane, so that the ejection liquid is moisturized.

[0003] Patent Document 1: Japanese Patent Application Publication No. 2019-123180

[0004] In such a liquid ejection device, when pressure is applied to the space storing the moisturizing liquid or the space storing the ejection liquid, a pressure difference is generated between the space storing the moisturizing liquid or the space storing the ejection liquid and the space inside the moisture permeable membrane. When a pressure difference is generated, there is a risk that the moisturizing liquid or the ejection liquid may seep into the moisture permeable membrane. Summary of the invention

[0005] A liquid storage portion for solving the above-mentioned problem comprises: a storage body for storing a spray liquid and a moisturizing liquid; and a moisture permeable membrane installed on the storage body, the moisture permeable membrane divides the storage body into a spray liquid chamber and a moisturizing liquid chamber, the spray liquid chamber is a space for storing the spray liquid, and the moisturizing liquid chamber is a space for storing the moisturizing liquid, and the storage body stores the spray liquid and the moisturizing liquid in such a manner that the liquid levels of the spray liquid stored in the spray liquid chamber and the liquid levels of the moisturizing liquid stored in the moisturizing liquid chamber are located below the upper end of the moisture permeable membrane.

[0006] The liquid flow mechanism for solving the above-mentioned problem comprises: the above-mentioned liquid storage part; a pressure changing mechanism connected to the storage body to change the pressure in the storage body; and a discharge liquid flow path connected to the storage body and communicated with the discharge liquid chamber.

[0007] A liquid ejection device that solves the above-mentioned problem comprises: the above-mentioned liquid flow mechanism; and an ejection portion connected to the storage body and ejecting the ejection liquid stored in the ejection liquid chamber. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 1 is a schematic diagram showing a first embodiment of a liquid ejecting device.

[0009] Figure 2 It is a schematic diagram showing a liquid storage part.

[0010] Figure 3 1 is a schematic diagram showing a second embodiment of the liquid ejecting device.

[0011] Figure 41 is a schematic diagram showing a third embodiment of the liquid ejecting device.

[0012] Figure 5 1 is a schematic diagram showing a fourth embodiment of the liquid ejecting device.

[0013] Figure 6 1 is a schematic diagram showing a fifth embodiment of the liquid ejecting device.

[0014] Figure 7 2 is a schematic diagram showing a sixth embodiment of the liquid ejecting device.

[0015] Figure 8 2 is a schematic diagram showing a seventh embodiment of the liquid ejecting device.

[0016] Fig. 9 1 is a schematic diagram showing an eighth embodiment of the liquid ejecting device.

[0017] Fig.10 2 is a schematic diagram showing a ninth embodiment of the liquid ejecting device.

[0018] Fig.11 1 is a schematic diagram showing a tenth embodiment of the liquid ejecting device.

[0019] Fig.12 is a schematic diagram showing an eleventh embodiment of the liquid ejecting device.

[0020] Fig.13 is a schematic diagram showing a twelfth embodiment of the liquid ejecting device.

[0021] Fig.14 is a schematic diagram showing a thirteenth embodiment of the liquid ejecting device.

[0022] Fig.15 is a schematic diagram showing a fourteenth embodiment of the liquid ejecting device.

[0023] Fig.16 is a schematic diagram showing a fifteenth embodiment of the liquid ejecting device.

[0024] Fig.17 is a schematic diagram showing a sixteenth embodiment of the liquid ejecting device.

[0025] Fig.18 is a schematic diagram showing a seventeenth embodiment of the liquid ejecting device.

[0026] Fig.19 is a schematic diagram showing an eighteenth embodiment of the liquid ejecting device.

[0027] Fig. 20 is a schematic diagram showing a nineteenth embodiment of the liquid ejecting device.

[0028] Fig.21 is a schematic diagram showing a twentieth embodiment of the liquid ejecting device.

[0029] Fig. 22 2 is a schematic diagram showing a twenty-first embodiment of the liquid ejecting device.

[0030] Fig.23 2 is a schematic diagram showing a twenty-second embodiment of the liquid ejecting device.

[0031] Fig.24 is a schematic diagram showing a twenty-third embodiment of the liquid ejecting device.

[0032] Fig.25 is a schematic diagram showing a twenty-fourth embodiment of the liquid ejecting device.

[0033] Fig.26 is a schematic diagram showing a twenty-fifth embodiment of the liquid ejecting device.

[0034] Fig. 27 is a schematic diagram showing a twenty-sixth embodiment of the liquid ejecting device.

[0035] Fig.28 is a schematic diagram showing a twenty-seventh embodiment of the liquid ejecting device.

[0036] Fig.29 is a schematic diagram showing a twenty-eighth embodiment of the liquid ejecting device.

[0037] Fig.30 is a schematic diagram showing a twenty-ninth embodiment of the liquid ejecting device.

[0038] Fig.31 is a schematic diagram showing a thirtieth embodiment of the liquid ejecting device.

[0039] Fig.32 is a schematic diagram showing a thirty-first embodiment of the liquid ejecting device.

[0040] Fig.33 is a schematic diagram showing a thirty-second embodiment of the liquid ejecting device.

[0041] Fig.34 is a schematic diagram showing a thirty-third embodiment of the liquid ejecting device.

[0042] Fig.35 is a schematic diagram showing a thirty-fourth embodiment of the liquid ejecting device.

[0043] Fig.36 is a schematic diagram showing a thirty-fifth embodiment of the liquid ejecting device.

[0044] Description of Reference Numerals

[0045] 11 ... liquid ejection device, 12 ... ejection portion, 13 ... nozzle, 14 ... nozzle surface, 15 ... introduction path, 16 ... common liquid chamber, 17 ... independent liquid chamber, 18 ... filter, 19 ... outlet path, 21 ... liquid flow mechanism, 22 ... ejection liquid supply source, 23 ... moisture supply source, 24 ... first liquid storage portion, 25 ... second liquid storage portion, 26 ... first storage body, 27 ... second storage body, 28 ... first storage chamber, 29 ... second storage chamber, 30 ... first moisture permeable membrane, 30H ... first pore, 30G ... first gap, 31 ... first ejection liquid chamber, 32 ... first moisturizing liquid chamber, 33 ... first upper end, 34 ... first lower end, 35 ... ejection liquid supply flow path, 36 ... moisture supply flow path, 37 ... ejection liquid supply valve, 38…Water supply valve, 39…Discharge liquid amount detection unit, 40…Moisturizing liquid amount detection unit, 41…Discharge liquid flow path, 42…First connection end, 43…Second connection end, 44…First connection flow path, 45…Second connection flow path, 46…Bypass flow path, 51…Pressure changing mechanism, 52…First changing unit, 53…Second changing unit, 54…First changing pump, 55…Second changing pump, 56…First pressure sensor, 57…Second pressure sensor, 58…First atmosphere release valve, 59…Second atmosphere release valve, 60…Liquid delivery pump, 61…Stirring unit, 62…Stirring flow path, 63…First end, 64…Second end, 65…Stirring pump, 67…Control unit, 71…First differential pressure valve, 72…Second differential pressure valve, 73…Supply pump, 74 ... first relay body, 75 ... second relay body, 76 ... first pressure regulating valve, 77 ... second pressure regulating valve, 78 ... common pump, 79 ... first regulator, 80 ... second regulator, 81 ... first switching valve, 82 ... second switching valve, 83 ... third liquid storage part, 84 ... third storage body, 85 ... third storage chamber, 86 ... first resistance part, 87 ... second resistance part, 88 ... check valve, 90 ... second moisture permeable membrane, 91 ... second ejection liquid chamber, 92 ... second moisturizing liquid chamber, 93 ... second upper end, 94 ... second lower end, 95 ... third moisture permeable membrane, 96 ... third ejection liquid chamber, 97 ... third moisturizing liquid chamber, 98 ... third upper end, 99 ... third lower end, 101 ... first circulation flow path, 102 ... second circulation flow path 103…relay tank, 104…relay pressure sensor, 105…first differential pressure regulating valve, 106…second differential pressure regulating valve, M1…medium, 111…liquid ejection device, 112…supply source, 113…ejection mechanism, 114…ejection portion, 115…nozzle, 116…nozzle surface, 117…introduction path, 118…common liquid chamber, 119…independent liquid chamber, 120…filter, 121…extraction path, 123…first ejection liquid storage portion, 124…second ejection liquid storage portion, 125…first ejection liquid chamber, 126…second ejection liquid chamber, 128…ejection liquid flow path, 129…ejection liquid supply flow path, 130…ejection liquid flow path, 131…first connecting flow path, 132…second connecting flow path,133 ... ejection liquid supply valve, 134 ... first ejection liquid amount detection unit, 135 ... pressure adjustment mechanism, 136 ... first adjustment unit, 137 ... second adjustment unit, 138 ... first adjustment pump, 139 ... second adjustment pump, 140 ... first pressure sensor, 141 ... second pressure sensor, 142 ... first atmosphere release valve, 143 ... second atmosphere release valve, 144 ... liquid delivery pump, 150 ... moisturizing mechanism, 151 ... first moisturizing liquid storage unit, 152 ... first moisturizing liquid chamber, 153 ... first moisturizing unit, 154 ... first moisture permeable membrane, 155 ... stirring unit, 156 ... stirring flow path, 157 ... first end, 158 ... second end, 159 ... stirring pump, 160 ... supply unit, 161 ... moisture storage unit, 162 ... moisture supply flow path, 163 ... moisture supply valve, 164 ... pressure reducing unit, 165 ... water pump, 1 66 ... first moisturizing liquid amount detection unit, 167 ... control unit, 170 ... ejection liquid pump, 171 ... third ejection liquid storage unit, 172 ... third ejection liquid chamber, 173 ... first switching valve, 174 ... second switching valve, 175 ... first resistance unit, 176 ... second resistance unit, 177 ... check valve, 178 ... first differential pressure valve, 179 ... second differential pressure valve, 180 ... moisturizing liquid atmosphere release valve, 181 ... first flexible membrane, 182 ... second flexible membrane, 183 ... third flexible membrane, 185 ... second moisturizing liquid storage unit, 186 ... second moisturizing liquid chamber, 187 ... second moisturizing unit, 188 ... second moisture permeable membrane, 189 ... first circulation flow path, 190 ... second circulation flow path, 191 ... maintenance unit, 192 ... cover, 193 ... absorbent material, 194 ... ejection liquid space, 195 ... moisturizing liquid space, M11 ... medium. , DETAILED DESCRIPTION

[0046] Hereinafter, one embodiment of a liquid ejecting device will be described with reference to the drawings. The liquid ejecting device is, for example, an inkjet printer that records images such as text and photographs by ejecting ink, which is an example of ejected liquid, onto a medium such as paper or cloth.

[0047] First embodiment

[0048] First, a first embodiment of the liquid ejecting device will be described.

[0049] like Figure 1 As shown, the liquid ejection device 11 includes an ejection unit 12. The ejection unit 12 is configured to eject the ejection liquid onto the medium M1. The ejection unit 12 is a so-called print head. The ejection unit 12 has a nozzle face 14 in which one or more nozzles 13 are opened. The ejection unit 12 ejects the ejection liquid from the nozzles 13.

[0050] The ejection portion 12 is formed with an introduction path 15, a common liquid chamber 16, and one or more independent liquid chambers 17. The introduction path 15, the common liquid chamber 16, and the one or more independent liquid chambers 17 are spaces within the ejection portion 12. The ejection liquid flows in the introduction path 15, the common liquid chamber 16, and the one or more independent liquid chambers 17.

[0051] The introduction path 15 is a space for introducing the ejection liquid into the ejection portion 12. The common liquid chamber 16 is connected to the introduction path 15. The ejection liquid is introduced into the common liquid chamber 16 through the introduction path 15. One or more independent liquid chambers 17 are connected to the common liquid chamber 16. The ejection liquid is introduced into one or more independent liquid chambers 17 through the common liquid chamber 16. In the case where the ejection portion 12 forms a plurality of independent liquid chambers 17, the plurality of independent liquid chambers 17 are connected to the common liquid chamber 16. One independent liquid chamber 17 is connected to one nozzle 13. Therefore, the ejection portion 12 is provided with the same number of independent liquid chambers 17 as the number of nozzles 13. The ejection portion 12 ejects the ejection liquid from the nozzle 13 by applying pressure to the ejection liquid located in the independent liquid chambers 17.

[0052] The ejection portion 12 may also include a filter 18. In one example, the filter 18 is located in the inlet path 15. Specifically, the filter 18 is located in the inlet path 15 at the end connected to the common liquid chamber 16. The filter 18 captures and collects bubbles, foreign matter, etc. contained in the ejection liquid. Thus, the ejection liquid from which bubbles, foreign matter, etc. are removed is introduced into the common liquid chamber 16 and the independent liquid chamber 17.

[0053] A guide path 19 may also be formed in the ejection portion 12. The guide path 19 is a space in the ejection portion 12 where the ejection liquid flows. The guide path 19 is a space for guiding the ejection liquid from the ejection portion 12. Therefore, the ejection liquid can flow in the ejection portion 12 from the introduction path 15 to the guide path 19. When the ejection liquid is retained for a long time, it is possible that viscosity increase or sedimentation occurs in the ejection liquid. By allowing the ejection liquid to flow in the ejection portion 12, the risk of viscosity increase or sedimentation occurring in the ejection liquid in the ejection portion 12 is reduced.

[0054] The lead-out path 19 extends from the lead-in path 15, the common liquid chamber 16, or the independent liquid chamber 17. In one example, the lead-out path 19 extends from the common liquid chamber 16. Therefore, the ejected liquid passes through the ejection portion 12 by flowing in the order of the lead-in path 15, the common liquid chamber 16, and the lead-out path 19. The lead-out path 19 may extend from the lead-in path 15 or from the independent liquid chamber 17. The lead-out path 19 may extend from the lead-in path 15 in such a manner that the ejected liquid passes through the ejection portion 12 without passing through the filter 18.

[0055] The ejection portion 12 is usually maintained at a negative pressure. This is to form a meniscus at the nozzle 13. As a result, the ejection portion 12 can properly eject the ejection liquid. Even when the ejection liquid flows from the inlet path 15 to the outlet path 19, the ejection portion 12 is maintained at a negative pressure. When the negative pressure of the ejection portion 12 is released, the meniscus may be destroyed. When the meniscus is destroyed, it is necessary to form a meniscus again at the nozzle 13.

[0056] The liquid ejection device 11 includes a liquid flow mechanism 21. The liquid flow mechanism 21 is a mechanism for making liquid flow. The liquid flow mechanism 21 makes the ejection liquid flow. The liquid flow mechanism 21 supplies the ejection liquid to the ejection portion 12 by making the ejection liquid flow. In addition to making the ejection liquid flow, the liquid flow mechanism 21 can also make a moisturizing liquid flow. The moisturizing liquid is a liquid for moisturizing the ejection liquid. The moisturizing liquid is, for example, a glycerin aqueous solution.

[0057] The liquid flow mechanism 21 is connected to a liquid supply source. The liquid supply source contains liquid. The liquid supply source includes a jetting liquid supply source 22 and a water supply source 23. The jetting liquid supply source 22 contains jetting liquid. The water supply source 23 contains water, i.e., water. The jetting liquid supply source 22 and the water supply source 23 may be a box, a bag, etc. that can be detachably mounted on the liquid jetting device 11, or may be a tank that can be replenished with liquid.

[0058] The liquid flow mechanism 21 has one or more liquid storage parts. In one example, the liquid flow mechanism 21 has a first liquid storage part 24 and a second liquid storage part 25. The liquid flow mechanism 21 may also have three or more liquid storage parts. The liquid storage part stores liquid. In detail, the liquid storage part stores the ejection liquid, or stores the ejection liquid and the moisturizing liquid. In one example, the first liquid storage part 24 stores the ejection liquid and the moisturizing liquid. The second liquid storage part 25 stores the ejection liquid.

[0059] The liquid storage portion is connected to the liquid supply source. Therefore, the ejection liquid is supplied from the ejection liquid supply source 22 to the liquid storage portion. Water is supplied from the water supply source 23 to the liquid storage portion. In one example, the first liquid storage portion 24 is connected to the ejection liquid supply source 22 and the water supply source 23. The second liquid storage portion 25 is connected to the first liquid storage portion 24. That is, the second liquid storage portion 25 is connected to the liquid supply source through the first liquid storage portion 24. Liquid is supplied from the first liquid storage portion 24 to the second liquid storage portion 25. In one example, the ejection liquid is supplied from the first liquid storage portion 24 to the second liquid storage portion 25. The first liquid storage portion 24 is not limited to being supplied with liquid from the liquid supply source, and may also be configured to be supplied with liquid from the second liquid storage portion 25. The second liquid storage portion 25 is not limited to being supplied with liquid from the first liquid storage portion 24, and may also be configured to be directly supplied with liquid from the liquid supply source.

[0060] The liquid storage part has a storage body. The storage body is configured to store the ejection liquid, or to store the ejection liquid and the moisturizing liquid. The first liquid storage part 24 has a first storage body 26. The second liquid storage part 25 has a second storage body 27. In one example, the first storage body 26 stores the ejection liquid and the moisturizing liquid. The second storage body 27 stores the ejection liquid.

[0061] The storage body defines a storage chamber. The storage chamber is a space for storing liquid. The first storage body 26 defines a first storage chamber 28. The second storage body 27 defines a second storage chamber 29. In one example, the first storage chamber 28 stores the spray liquid and the moisturizing liquid. The second storage chamber 29 stores the spray liquid.

[0062] The liquid storage part has a moisture permeable membrane. Specifically, at least one of the plurality of liquid storage parts has a moisture permeable membrane. For example, at least one of the first liquid storage part 24 and the second liquid storage part 25 has a moisture permeable membrane. That is, only the first liquid storage part 24 may have a moisture permeable membrane, only the second liquid storage part 25 may have a moisture permeable membrane, or both the first liquid storage part 24 and the second liquid storage part 25 may have a moisture permeable membrane. In one example, the first liquid storage part 24 has a moisture permeable membrane, and the second liquid storage part 25 does not have a moisture permeable membrane. The first liquid storage part 24 has a first moisture permeable membrane 30.

[0063] The moisture permeable membrane is installed on the storage body. The moisture permeable membrane divides the storage body into a spraying liquid chamber and a moisturizing liquid chamber. That is, the moisture permeable membrane separates the spraying liquid chamber from the moisturizing liquid chamber. In one example, the first moisture permeable membrane 30 is installed on the first storage body 26. The first moisture permeable membrane 30 divides the first storage body 26 into a first spraying liquid chamber 31 and a first moisturizing liquid chamber 32.

[0064] The spray liquid chamber is a space for storing the spray liquid. The spray liquid is supplied to the spray liquid chamber. In one example, the spray liquid is supplied from the spray liquid supply source 22 to the first spray liquid chamber 31. The moisturizing liquid chamber is a space for storing the moisturizing liquid. Water is supplied to the moisturizing liquid chamber. That is, water is supplied to the moisturizing liquid stored in the moisturizing liquid chamber. In one example, water is supplied from the water supply source 23 to the first moisturizing liquid chamber 32.

[0065] The moisture permeable membrane is a membrane that allows gas to pass through but does not allow liquid to pass through. Therefore, the moisture permeable membrane separates the ejection liquid and the moisturizing liquid in such a way that the ejection liquid stored in the ejection liquid chamber and the moisturizing liquid stored in the moisturizing liquid chamber do not mix. The moisture permeable membrane is a porous membrane formed with a plurality of pores. The moisture permeable membrane defines a gap connected to the plurality of pores. The gap is a space within the moisture permeable membrane. In the pore, a curved liquid surface is generated due to the surface tension of the liquid. The curved liquid surface is the gas-liquid interface between the liquid stored in the liquid chamber and the gas located in the gap. Thus, the moisture permeable membrane allows gas to pass through but does not allow liquid to pass through.

[0066] like Figure 2 As shown, a plurality of first pores 30H are formed in the first moisture permeable film 30. A first gap 30G through which the plurality of first pores 30H pass is formed in the first moisture permeable film 30. The first gap 30G is located between the first ejection liquid chamber 31 and the first moisturizing liquid chamber 32 in the first storage chamber 28. The first gap 30G communicates with the first ejection liquid chamber 31 and the first moisturizing liquid chamber 32 through the first pores 30H. A meniscus of the ejection liquid or a meniscus of the moisturizing liquid is formed in the first pores 30H.

[0067] The moisture permeable membrane has an upper end and a lower end. The lower end of the moisture permeable membrane is mounted on the storage body. The upper end of the moisture permeable membrane is located above the spraying liquid surface and the moisturizing liquid surface. That is, the storage body stores the spraying liquid and the moisturizing liquid in such a manner that the upper end of the moisture permeable membrane is located above the spraying liquid surface and the moisturizing liquid surface. The first moisture permeable membrane 30 has a first upper end 33 and a first lower end 34. The first upper end 33 is located above the spraying liquid surface of the first spraying liquid chamber 31 and the moisturizing liquid surface of the first moisturizing liquid chamber 32. That is, the first storage body 26 stores the spraying liquid and the moisturizing liquid in such a manner that the first upper end 33 is located above the spraying liquid surface of the first spraying liquid chamber 31 and the moisturizing liquid surface of the first moisturizing liquid chamber 32.

[0068] The moisture permeable film may also completely divide the interior of the storage body. In one example, the first moisture permeable film 30 completely divides the interior of the first storage body 26. That is, the first upper end 33 and the first lower end 34 are attached to the first storage body 26. Thus, even if the spray liquid splashes or the moisturizing liquid splashes, the spray liquid and the moisturizing liquid cannot be mixed.

[0069] In the ejection liquid, water may evaporate over time. When water evaporates from the ejection liquid, the concentration of the ejection liquid increases. When the concentration of the ejection liquid increases, the ejection liquid may become thicker. When the ejection liquid becomes thicker, the ejection unit 12 may not be able to eject the ejection liquid properly.

[0070] The moisturizing liquid moisturizes the spray liquid through the moisture permeable membrane. In detail, the moisturizing liquid supplies water to the spray liquid through the moisture permeable membrane to moisturize the spray liquid. The water contained in the moisturizing liquid passes through the moisture permeable membrane as water vapor. Thus, the water is supplied to the spray liquid. In one example, the water of the moisturizing liquid stored in the first moisturizing liquid chamber 32 passes through the first moisture permeable membrane 30 and is supplied to the spray liquid stored in the first spray liquid chamber 31. The movement speed of the water supplied from the moisturizing liquid to the spray liquid is determined by the contact area between the spray liquid and the moisturizing liquid through the moisture permeable membrane. The larger the contact area between the spray liquid and the moisturizing liquid through the moisture permeable membrane, the greater the movement speed of the water. The movement speed of the water only needs to be greater than the evaporation speed of the spray liquid. In addition, the movement speed of the water supplied from the moisturizing liquid to the spray liquid is also determined by the thickness of the moisture permeable membrane. The thinner the thickness of the moisture permeable membrane, the greater the movement speed of the water.

[0071] For the moisturizing liquid, an appropriate concentration is set in order to moisturize the ejected liquid. In detail, the concentration of the moisturizing liquid is set in such a way that the moisturizing power of the new ejected liquid is balanced with the moisturizing power of the moisturizing liquid. The moisturizing power is the ease of releasing moisture. That is, the greater the moisturizing power, the easier it is to supply moisture. Assuming that the moisturizing power of the moisturizing liquid stored in the moisturizing liquid chamber is smaller than the moisturizing power of the new ejected liquid, water moves from the ejected liquid to the moisturizing liquid. In this case, it is possible to promote an increase in the concentration of the ejected liquid. On the contrary, when the moisturizing power of the moisturizing liquid stored in the moisturizing liquid chamber is greater than the moisturizing power of the new ejected liquid, the concentration of the ejected liquid may drop too much. Therefore, in order to keep the ejected liquid at an appropriate concentration, the liquid storage unit stores the moisturizing liquid at an appropriate concentration when moisturizing the ejected liquid. Thus, when the moisturizing power of the ejected liquid decreases due to evaporation of water in the ejected liquid, water moves from the moisturizing liquid to the ejected liquid.

[0072] As water moves from the moisturizing liquid to the ejection liquid, the amount of water in the moisturizing liquid decreases. In the moisturizing liquid, water sometimes evaporates over time, similarly to the ejection liquid. Therefore, the concentration of the moisturizing liquid may increase. When the concentration of the moisturizing liquid increases, it may be impossible to moisturize the ejection liquid. In this regard, by supplying water from the water supply source 23 to the moisturizing liquid chamber, the risk of the moisturizing liquid concentration increasing is reduced.

[0073] The storage body stores liquid and air in the storage chamber. Specifically, the storage body stores the ejection liquid and air in the ejection liquid chamber. The storage body stores the moisturizing liquid and air in the moisturizing liquid chamber. Therefore, there is a liquid level of the ejection liquid in the ejection liquid chamber. There is a liquid level of the moisturizing liquid in the moisturizing liquid chamber. In the liquid flow mechanism 21, the amount of liquid stored in the storage body is controlled in such a manner that the storage body stores the liquid together with the air. Since the storage body stores the air together with the liquid, the upper end of the moisture permeable membrane can be located above the liquid level.

[0074] Since the upper end of the moisture permeable membrane is located above the liquid surface, the spray liquid and the moisturizing liquid cannot enter and exit the spray liquid chamber and the moisturizing liquid chamber through the moisture permeable membrane, while the air can enter and exit through the moisture permeable membrane. In detail, the air can enter and exit the gap between the spray liquid chamber and the moisture permeable membrane. The air can enter and exit the gap between the moisturizing liquid chamber and the moisture permeable membrane. Therefore, when the spray liquid chamber is pressurized or the spray liquid chamber is decompressed, the air moves in the spray liquid chamber and the gap, so that it is difficult to generate a pressure difference between the spray liquid chamber and the gap. When the moisturizing liquid chamber is pressurized or the moisturizing liquid chamber is decompressed, the air moves in the moisturizing liquid chamber and the gap, so that it is difficult to generate a pressure difference between the moisturizing liquid chamber and the gap. For example, when the liquid flow mechanism 21 causes the spray liquid or the moisturizing liquid to flow, the pressure in the storage body may change. In this case, it is difficult to generate a pressure difference between the spray liquid chamber and the gap by the air moving in the spray liquid chamber and the gap. By moving the air in the moisturizing liquid chamber and the gap, it is difficult to generate a pressure difference in the moisturizing liquid chamber and the gap. Thus, the risk of liquid seeping into the moisture permeable membrane is reduced. In one example, since no pressure difference is generated in the first ejection liquid chamber 31 and the first gap 30G, the risk of the ejection liquid seeping into the first gap 30G is reduced. Since no pressure difference is generated in the first moisturizing liquid chamber 32 and the first gap 30G, the risk of the moisturizing liquid seeping into the first gap 30G is reduced. Assuming that a pressure difference is generated in the ejection liquid chamber or the moisturizing liquid chamber and the gap, the curved liquid surface formed in the pores of the moisture permeable membrane may be destroyed. For example, when the upper end of the moisture permeable membrane is located below the ejection liquid surface and the moisturizing liquid surface, it is difficult for air to enter and exit the ejection liquid chamber and the moisturizing liquid chamber and the gap. Therefore, when the ejection liquid chamber is pressurized or the ejection liquid chamber is decompressed, a pressure difference is generated in the ejection liquid chamber and the gap. In addition, when the moisturizing liquid chamber is pressurized or depressurized, a pressure difference is generated between the moisturizing liquid chamber and the gap. When the meniscus is destroyed, there is a possibility that the ejection liquid seeps through the moisture permeable membrane into the moisturizing liquid chamber, or the moisturizing liquid seeps through the moisture permeable membrane into the ejection liquid chamber.

[0075] like Figure 1 As shown, the liquid flow mechanism 21 has a liquid supply flow path. The liquid supply flow path is a flow path for supplying liquid from a liquid supply source to a liquid storage portion. The liquid supply flow path includes a spray liquid supply flow path 35 and a moisture supply flow path 36. The spray liquid supply flow path 35 is a flow path for supplying spray liquid from a spray liquid supply source 22 to a liquid storage portion. In one example, the spray liquid supply flow path 35 is connected to the spray liquid supply source 22 and the first storage body 26. The spray liquid supply flow path 35 is connected to the first spray liquid chamber 31. The moisture supply flow path 36 is a flow path for supplying water from a moisture supply source 23 to a liquid storage portion. In one example, the moisture supply flow path 36 is connected to the moisture supply source 23 and the first storage body 26. The moisture supply flow path 36 is connected to the first moisturizing liquid chamber 32.

[0076] The liquid flow mechanism 21 has a liquid supply valve. The liquid supply valve is located in the liquid supply flow path. The liquid supply valve includes a jet liquid supply valve 37 and a water supply valve 38. The jet liquid supply valve 37 is located in the jet liquid supply flow path 35. When the jet liquid supply valve 37 is opened, the jet liquid can be supplied from the jet liquid supply source 22 to the first storage body 26. The water supply valve 38 is located in the water supply flow path 36. When the water supply valve 38 is opened, water can be supplied from the water supply source 23 to the first storage body 26. Normally, the liquid supply valve is closed. When it is necessary to supply liquid to the storage body, the liquid supply valve is opened.

[0077] The liquid flow mechanism 21 has a liquid amount detection unit. The liquid amount detection unit is configured to detect the amount of liquid stored in the storage body. The liquid amount detection unit includes a discharge liquid amount detection unit 39 and a moisturizing liquid amount detection unit 40. The discharge liquid amount detection unit 39 detects the amount of discharge liquid stored in the storage body. The moisturizing liquid amount detection unit 40 detects the amount of moisturizing liquid stored in the storage body.

[0078] The liquid amount detection unit is mounted on the storage body. The liquid amount detection unit is mounted, for example, on the first storage body 26. The ejection liquid amount detection unit 39 is mounted on the first storage body 26. The ejection liquid amount detection unit 39 detects the amount of the ejection liquid stored in the first ejection liquid chamber 31. The moisturizing liquid amount detection unit 40 is mounted on the first storage body 26. The moisturizing liquid amount detection unit 40 detects the amount of the moisturizing liquid stored in the first moisturizing liquid chamber 32. The liquid amount detection unit is not limited to being mounted on the first storage body 26, but may be mounted on other storage bodies. For example, the liquid amount detection unit may be mounted on the second storage body 27.

[0079] The liquid amount detection unit may detect the liquid amount based on the conduction of electricity between electrodes, or may detect the liquid amount based on the reflected light of a prism. The liquid amount detection unit may also detect the liquid amount based on the vibration waveform of the liquid by a piezoelectric sensor. The liquid amount detection unit may also detect the liquid amount based on the pressure of the liquid detected by a pressure sensor. By detecting the liquid amount by the liquid amount detection unit, the storage body can store air together with the liquid. That is, the liquid amount of the storage body is controlled by the liquid amount detection unit. By controlling the liquid amount based on the liquid amount detection unit, the storage body stores air together with the liquid.

[0080] The amount of moisturizing liquid is detected by the liquid amount detection unit, and the amount of moisturizing liquid in the reservoir is controlled. By controlling the amount of moisturizing liquid in the reservoir, the moisturizing liquid is maintained at an appropriate concentration. When water is supplied to the moisturizing liquid stored in the moisturizing liquid chamber, the concentration of the moisturizing liquid decreases. That is, the amount of water supplied affects the moisturizing power of the moisturizing liquid. Therefore, by supplying water in such a manner that the amount of moisturizing liquid stored in the reservoir becomes constant, the moisturizing liquid stored in the moisturizing liquid chamber is maintained at an appropriate concentration. In one example, by supplying water in such a manner that the amount of moisturizing liquid stored in the first moisturizing liquid chamber 32 becomes constant based on the detection result of the moisturizing liquid amount detection unit 40, the moisturizing liquid stored in the first moisturizing liquid chamber 32 is maintained at an appropriate concentration.

[0081] The liquid flow mechanism 21 has a discharge liquid flow path 41. The discharge liquid flow path 41 is a flow path through which the discharge liquid flows. The discharge liquid flow path 41 is a flow path for causing the discharge liquid stored in the storage body to flow. The discharge liquid flow path 41 may include a flow path for circulating the discharge liquid, and may also include a flow path for supplying the discharge liquid to the discharge portion 12. In one example, the discharge liquid flow path 41 is a flow path for circulating the discharge liquid, and is also a flow path for supplying the discharge liquid to the discharge portion 12. Therefore, the discharge portion 12 can discharge the discharge liquid stored in the storage body.

[0082] The ejection liquid flow path 41 is connected to the storage body. In one example, the ejection liquid flow path 41 is connected to the first storage body 26 and the second storage body 27. The ejection liquid flow path 41 is connected to the storage chamber. In detail, the ejection liquid flow path 41 is connected to the first ejection liquid chamber 31. The ejection liquid flow path 41 is connected to the second storage chamber 29. Through the ejection liquid flow path 41, the ejection liquid can flow into the storage chamber, and the ejection liquid can also flow out of the storage chamber.

[0083] The ejection liquid flow path 41 has a first connection end 42 and a second connection end 43. The first connection end 42 and the second connection end 43 are ends of the ejection liquid flow path 41. The first connection end 42 and the second connection end 43 are connected to a storage body. For example, the first connection end 42 and the second connection end 43 are connected to the first storage body 26. The first connection end 42 and the second connection end 43 are connected to the first ejection liquid chamber 31. The ejection liquid circulates by flowing through the ejection liquid flow path 41. The circulated ejection liquid is moisturized by the moisturizing liquid. Therefore, the entire ejection liquid is moisturized by the moisturizing liquid.

[0084] The ejection liquid flow path 41 has a first connecting flow path 44 and a second connecting flow path 45. The first connecting flow path 44 is connected to the first reservoir 26 and the second reservoir 27. The first connecting flow path 44 has a first connecting end 42. The second connecting flow path 45 is connected to the first reservoir 26 and the second reservoir 27. The second connecting flow path 45 has a second connecting end 43. The first connecting flow path 44 and the second connecting flow path 45 circulate the ejection liquid and supply the ejection liquid to the ejection portion 12.

[0085] The ejection liquid flow path 41 is connected to the ejection portion 12. In detail, the ejection portion 12 is located in the ejection liquid flow path 41. Therefore, the ejection liquid is supplied from the reservoir to the ejection portion 12 through the ejection liquid flow path 41. In one example, the ejection portion 12 is located in the first connection flow path 44. Therefore, the ejection liquid circulates in the ejection portion 12, the first reservoir 26, and the second reservoir 27 through the ejection liquid flow path 41. For example, the ejection liquid flows from the second reservoir 27 to the first reservoir 26 through the first connection flow path 44 when circulating. The ejection liquid flows from the first reservoir 26 to the second reservoir 27 through the second connection flow path 45 when circulating.

[0086] The ejection liquid flow path 41 may include a flow path for circulating the ejection liquid and a flow path for supplying the ejection liquid to the ejection portion 12, respectively and independently. The ejection liquid flow path 41 may include, for example, a bypass flow path 46. The bypass flow path 46 is a flow path for circulating the ejection liquid without passing through the ejection portion 12. The bypass flow path 46 is connected to the first storage body 26. In this case, both ends of the bypass flow path 46 correspond to the first connection end 42 and the second connection end 43. The ejection liquid flow path 41 may include a liquid supply flow path connected to the first storage body 26 and the ejection portion 12 in addition to the bypass flow path 46.

[0087] The liquid flow mechanism 21 has a pressure changing mechanism 51. The pressure changing mechanism 51 is connected to the liquid storage part. The pressure changing mechanism 51 is a mechanism for changing the pressure in the storage body. The pressure changing mechanism 51 causes the liquid to flow by changing the pressure in the storage body. The pressure changing mechanism 51 changes the pressure in the first storage body 26. The pressure changing mechanism 51 changes the pressure in the second storage body 27.

[0088] The pressure changing mechanism 51 is connected to the storage body. The pressure changing mechanism 51 is connected to the first storage body 26. The pressure changing mechanism 51 is connected to the second storage body 27. The pressure changing mechanism 51 is connected to the first storage chamber 28. In one example, the pressure changing mechanism 51 is connected to the first ejection liquid chamber 31 and the first moisturizing liquid chamber 32. The pressure changing mechanism 51 is connected to the second storage chamber 29.

[0089] The pressure changing mechanism 51 generates a pressure difference between the first reservoir 26 and the second reservoir 27. As a result, the liquid flows through the first reservoir 26 and the second reservoir 27. In one example, the ejected liquid flows from the second reservoir 27 to the first reservoir 26 through the first connecting flow path 44. As a result, the liquid circulates through the first reservoir 26 and the second reservoir 27.

[0090] When the pressure changing mechanism 51 changes the pressure in the storage chamber, it can change the pressure in the ejection liquid chamber or the moisturizing liquid chamber. In any case, since air enters and exits the ejection liquid chamber and the moisturizing liquid chamber through the moisture permeable membrane, the pressure in the ejection liquid chamber and the moisturizing liquid chamber change in the same manner. Therefore, the pressure changing mechanism 51 can pressurize or depressurize the first ejection liquid chamber 31 or the first moisturizing liquid chamber 32.

[0091] The pressure changing mechanism 51 has a changing portion. The changing portion is connected to the storage body. In one example, the pressure changing mechanism 51 has a first changing portion 52 and a second changing portion 53. The first changing portion 52 is connected to the first storage body 26. The second changing portion 53 is connected to the second storage body 27.

[0092] The variable part varies the pressure in the storage body. The variable part pressurizes or depressurizes the storage body. The variable part is connected to the upper part of the storage chamber. That is, the variable part is connected to the air stored in the storage body. The variable part varies the pressure in the storage body by sending air into the storage body or sucking air from the storage body. The variable part causes the liquid to flow by varying the pressure in the storage body. The first variable part 52 varies the pressure in the first storage body 26. The first variable part 52 is connected to the upper part of the first storage chamber 28. The second variable part 53 varies the pressure in the second storage body 27. The second variable part 53 is connected to the upper part of the second storage chamber 29.

[0093] The first variation section 52 and the second variation section 53 vary the pressure in the first reservoir 26 and the pressure in the second reservoir 27 so that a pressure difference is generated in the first reservoir 26 and the second reservoir 27. Specifically, the first variation section 52 and the second variation section 53 vary the pressure in the first reservoir 26 and the pressure in the second reservoir 27 so that the pressure in the first reservoir 26 is lower than the pressure in the second reservoir 27. Thus, the ejection liquid flows from the second reservoir 27 to the first reservoir 26 through the first connecting flow path 44. That is, the ejection liquid flows in the ejection section 12 from the introduction path 15 toward the outlet path 19.

[0094] The first varying portion 52 varies the pressure in the first reservoir 26 so that the inside of the ejection portion 12 is always maintained at a predetermined negative pressure. The second varying portion 53 varies the pressure in the second reservoir 27 so that the inside of the ejection portion 12 is always maintained at a predetermined negative pressure. Thus, the ejection liquid can be appropriately ejected from the ejection portion 12 while the ejection liquid flows from the second reservoir 27 to the first reservoir 26.

[0095] The variable part has a variable pump. The variable pump is connected to the storage body. The variable pump is a pump that varies the pressure in the storage body. The variable pump is, for example, a diaphragm pump. The first variable part 52 has a first variable pump 54. The first variable pump 54 is, for example, a pressure reducing pump. The first variable pump 54 is connected to the first storage body 26. The first variable pump 54 depressurizes the first storage body 26. In detail, the first variable pump 54 depressurizes the first storage body 26 by sucking air from the first storage body 26. The second variable part 53 has a second variable pump 55. The second variable pump 55 is, for example, a pressure increasing pump. The second variable pump 55 is connected to the second storage body 27. The second variable pump 55 pressurizes the second storage body 27. In detail, the second variable pump 55 pressurizes the second storage body 27 by sending air into the second storage body 27.

[0096] The first variable displacement pump 54 is driven to allow liquid to flow into the first reservoir 26. When the first variable displacement pump 54 depressurizes the first reservoir 26, the liquid flows into the first reservoir 26. For example, when the first variable displacement pump 54 depressurizes the first reservoir 26, the ejection liquid can flow into the first reservoir 26 from the ejection liquid supply source 22. When the first variable displacement pump 54 depressurizes the first reservoir 26, water can flow into the first reservoir 26 from the water supply source 23. When the first variable displacement pump 54 depressurizes the first reservoir 26, the ejection liquid flows into the first reservoir 26 from the ejection portion 12 through the first connecting flow path 44.

[0097] The second variable pump 55 is driven to cause the liquid to flow out of the second reservoir 27. When the second variable pump 55 pressurizes the second reservoir 27, the liquid flows out of the second reservoir 27. For example, when the second variable pump 55 pressurizes the inside of the second reservoir 27, the ejection liquid flows out from the second reservoir 27 toward the ejection portion 12 through the first connecting flow path 44.

[0098] The second variable pump 55 is not limited to a pressurizing pump, and may be a depressurizing pump like the first variable pump 54, or may be a pump capable of pressurizing and depressurizing the inside of the second reservoir 27. In this case, the second variable pump 55 depressurizes the inside of the second reservoir 27 so that the pressure inside the second reservoir 27 is higher than the pressure inside the first reservoir 26. In this case, since a pressure difference is generated between the first reservoir 26 and the second reservoir 27, the ejection liquid also flows from the second reservoir 27 to the first reservoir 26 through the first connecting flow path 44. In addition, by depressurizing the inside of the second reservoir 27 by the second variable pump 55, the ejection liquid can flow back from the ejection portion 12 to the second reservoir 27. In this case, since the bubbles captured and collected by the filter 18 flow to the second reservoir 27, the bubbles can be removed from the filter 18.

[0099] The variable part has a pressure sensor. The pressure sensor is connected to the storage body. The pressure sensor detects the pressure in the storage body. The first variable part 52 has a first pressure sensor 56. The first pressure sensor 56 is connected to the first storage body 26. The first pressure sensor 56 detects the pressure in the first storage body 26. The second variable part 53 has a second pressure sensor 57. The second pressure sensor 57 is connected to the second storage body 27. The second pressure sensor 57 detects the pressure in the second storage body 27. In the variable part, the variable pump is driven based on the detection result of the pressure sensor. As a result, the inside of the ejection part 12 is maintained at a predetermined negative pressure.

[0100] The variable part has an atmospheric opening valve. The atmospheric opening valve is connected to the storage body. The atmospheric opening valve is a valve that opens the inside of the storage body to the atmosphere. The first variable part 52 has a first atmospheric opening valve 58. The first atmospheric opening valve 58 is connected to the first storage body 26. The first atmospheric opening valve 58 opens the inside of the first storage body 26 to the atmosphere. The second variable part 53 has a second atmospheric opening valve 59. The second atmospheric opening valve 59 is connected to the second storage body 27. The second atmospheric opening valve 59 opens the inside of the second storage body 27 to the atmosphere. In order to suppress the evaporation of the liquid in the storage body, the atmospheric opening valve includes a capillary that connects the inside of the storage body to the atmosphere. Since the flow path resistance of the capillary is large, it is difficult for the liquid to evaporate. That is, the water contained in the spray liquid and the water contained in the moisturizing liquid are difficult to evaporate.

[0101] The pressure varying mechanism 51 includes a liquid delivery pump 60 for causing the liquid to flow. The liquid delivery pump 60 is located in the second connecting flow path 45. The liquid delivery pump 60 delivers the ejected liquid from the first storage body 26 to the second storage body 27 through the second connecting flow path 45. Therefore, in one example, the ejected liquid circulates through the first variable pump 54, the second variable pump 55, and the liquid delivery pump 60.

[0102] The liquid delivery pump 60 may be located in the bypass flow path 46. Specifically, when the ejection liquid flow path 41 has the bypass flow path 46, the liquid delivery pump 60 may be located in the bypass flow path 46. In this case, when the liquid delivery pump 60 is driven, the pressure in the first storage body 26 fluctuates, and the ejection liquid circulates in the bypass flow path 46.

[0103] The liquid flow mechanism 21 includes a stirring portion 61. The stirring portion 61 is configured to stir the moisturizing liquid. The concentration of the moisturizing liquid is made uniform by stirring the moisturizing liquid by the stirring portion 61. Thus, the risk of the moisturizing liquid concentration becoming high is reduced.

[0104] The stirring part 61 is attached to the reservoir. The stirring part 61 stirs the moisturizing liquid stored in the reservoir. In one example, the stirring part 61 is attached to the first reservoir 26. The stirring part 61 stirs the moisturizing liquid stored in the first reservoir 26. That is, the stirring part 61 stirs the moisturizing liquid stored in the first moisturizing liquid chamber 32.

[0105] The stirring portion 61 has a stirring flow path 62. The stirring flow path 62 has a first end 63 and a second end 64. The first end 63 and the second end 64 are connected to the first storage body 26. The first end 63 and the second end 64 are connected to the first moisturizing liquid chamber 32. In one example, the stirring flow path 62 constitutes a part of the moisture supply flow path 36. For example, the first end 63 coincides with the end of the moisture supply flow path 36. The stirring flow path 62 may also be a flow path independent of the moisture supply flow path 36.

[0106] The stirring section 61 has a stirring pump 65. The stirring pump 65 is located in the stirring flow path 62. The stirring pump 65 circulates the moisturizing liquid in the first storage body 26 through the stirring flow path 62. Thus, the moisturizing liquid is stirred. In one example, when the stirring pump 65 is driven, the moisturizing liquid flows through the stirring flow path 62 from the first end 63 toward the second end 64. That is, the moisturizing liquid circulates in the stirring flow path 62.

[0107] The stirring section 61 is not limited to the one having the stirring flow path 62 and the stirring pump 65, but may also have a fin for stirring the moisturizing liquid in the first storage body 26. In this case, the moisturizing liquid in the first moisturizing liquid chamber 32 is stirred by driving the fin.

[0108] The liquid ejection device 11 includes a control unit 67. The control unit 67 controls various components of the liquid ejection device 11. The control unit 67 controls the ejection unit 12. The control unit 67 controls the liquid flow mechanism 21. For example, the control unit 67 controls the ejection liquid supply valve 37, the water supply valve 38, the pressure change mechanism 51, and the stirring unit 61.

[0109] The control unit 67 may also be composed of one or more processors that execute various processes according to a computer program. The control unit 67 may also be composed of one or more dedicated hardware circuits such as an ASIC that executes at least a part of the various processes. The control unit 67 may also be composed of a circuit including a combination of a processor and a hardware circuit. The processor includes a CPU and a memory such as a RAM and a ROM. The memory stores program codes or instructions configured to cause the CPU to execute a process. The memory, i.e., a computer-readable medium, includes any readable medium that can be accessed by a general-purpose or special-purpose computer.

[0110] The control unit 67 drives the first variable pump 54 so that a predetermined negative pressure is maintained in the ejection unit 12. The control unit 67 drives the second variable pump 55 so that a predetermined negative pressure is maintained in the ejection unit 12. Furthermore, the control unit 67 drives the liquid delivery pump 60. Thus, the control unit 67 circulates the ejection liquid. The circulated ejection liquid is moisturized by the moisturizing liquid.

[0111] The control unit 67 may supply water from the water supply source 23 to the first storage body 26 by driving the stirring unit 61. The control unit 67 may also supply water from the water supply source 23 to the first storage body 26 by driving the stirring pump 65 in a state where the water supply valve 38 is opened. Thus, the control unit 67 supplies water to the moisturizing liquid stored in the first moisturizing liquid chamber 32.

[0112] The control unit 67 may circulate the moisturizing liquid by driving the stirring unit 61. The control unit 67 drives the stirring pump 65 in a state where the water supply valve 38 is closed, thereby circulating the moisturizing liquid.

[0113] The control unit 67 can circulate the liquid all the time, or can circulate the liquid at a predetermined timing. That is, the control unit 67 can circulate the ejection liquid and the moisturizing liquid all the time, or can circulate them at a predetermined timing. The control unit 67 can also circulate the liquid during printing. The control unit 67 can also circulate the liquid during the maintenance of the liquid ejection device 11. The control unit 67 can also circulate the liquid when it is judged that the liquid needs to be circulated. The control unit 67 can also judge whether the liquid needs to be circulated based on the temperature and humidity during printing, the printing duty cycle, the elapsed time, etc. For example, the control unit 67 judges that the liquid needs to be circulated when the temperature and humidity are high. The control unit 67 judges that the liquid needs to be circulated when the printing duty cycle is small. The control unit 67 judges that the liquid needs to be circulated when the elapsed time is long. The elapsed time is the time that has passed since the last printing, the time that has passed since the last liquid supply, etc.

[0114] The control unit 67 controls the liquid supply valve based on the detection result of the liquid amount detection unit. That is, the control unit 67 controls the discharge liquid supply valve 37 based on the detection result of the discharge liquid amount detection unit 39. The control unit 67 controls the moisture supply valve 38 based on the detection result of the moisturizing liquid amount detection unit 40.

[0115] When the amount of the ejected liquid detected by the ejected liquid amount detection unit 39 is less than the threshold value, the control unit 67 opens the ejected liquid supply valve 37. As a result, the ejected liquid can be supplied from the ejected liquid supply source 22 to the first reservoir 26. At this time, the control unit 67 causes the first variable unit 52 to reduce the pressure in the first reservoir 26, thereby supplying the ejected liquid from the ejected liquid supply source 22 to the first reservoir 26. When the amount of the ejected liquid detected by the ejected liquid amount detection unit 39 is greater than the threshold value, the control unit 67 closes the ejected liquid supply valve 37. As a result, the amount of the ejected liquid stored in the first reservoir 26 is maintained to be greater than the threshold value.

[0116] When the amount of moisturizing liquid detected by the moisturizing liquid amount detection unit 40 is below the threshold value, the control unit 67 opens the water supply valve 38. Thus, water can be supplied from the water supply source 23 to the first storage body 26. At this time, the control unit 67 supplies water from the water supply source 23 to the first storage body 26 by causing the first variable unit 52 to decompress the inside of the first storage body 26. When the amount of moisturizing liquid detected by the moisturizing liquid amount detection unit 40 is greater than the threshold value, the control unit 67 closes the water supply valve 38. Thus, the amount of moisturizing liquid stored in the first storage body 26 is maintained in a state greater than the threshold value. Therefore, the moisturizing liquid is maintained at an appropriate concentration. The threshold value of the ejection liquid amount and the threshold value of the moisturizing liquid amount may be different values.

[0117] The control unit 67 may supply the liquid from the liquid supply source to the first reservoir 26 not through the first variation unit 52 but through the head difference between the liquid supply source and the first reservoir 26. In this case, the liquid level stored in the liquid supply source is located above the liquid level stored in the first reservoir 26. The control unit 67 supplies the liquid to the first reservoir 26 by opening the liquid supply valve based on the detection result of the liquid amount detection unit.

[0118] Function and effect

[0119] Next, the operation and effects of the first embodiment will be described.

[0120] (1) The first storage body 26 stores the spray liquid and the moisturizing liquid in such a manner that the liquid level of the spray liquid stored in the first spray liquid chamber 31 and the liquid level of the moisturizing liquid stored in the first moisturizing liquid chamber 32 are located below the first upper end 33. According to the above structure, the spray liquid and air are stored in the first spray liquid chamber 31, and the moisturizing liquid and air are stored in the first moisturizing liquid chamber 32. The air can move between the first spray liquid chamber 31 and the first gap 30G. The air can move between the first moisturizing liquid chamber 32 and the first gap 30G. Therefore, even if pressure is applied to the spray liquid, it is difficult to generate a pressure difference between the first spray liquid chamber 31 and the first gap 30G. Even if pressure is applied to the moisturizing liquid, it is difficult to generate a pressure difference between the first moisturizing liquid chamber 32 and the first gap 30G. As a result, the risk of liquid seeping into the first moisture permeable membrane 30 is reduced.

[0121] (2) The first storage body 26 is connected to the pressure changing mechanism 51 in such a manner that the upper portion of the first ejection liquid chamber 31 or the upper portion of the first moisturizing liquid chamber 32 communicates with the pressure changing mechanism 51. According to the above structure, even if the pressure changing mechanism 51 changes the pressure of the first ejection liquid chamber 31 or the first moisturizing liquid chamber 32, it is difficult to generate a pressure difference between the first ejection liquid chamber 31 or the first moisturizing liquid chamber 32 and the first gap 30G. As a result, the risk of liquid seeping into the first moisture permeable membrane 30 is reduced.

[0122] (3) The liquid flow mechanism 21 is a discharge liquid flow path 41 connected to the first storage body 26, and includes a discharge liquid flow path 41 that communicates with the first discharge liquid chamber 31. The pressure in the first storage body 26 is varied by the pressure variation mechanism 51, so that the liquid in the first discharge liquid chamber 31 flows in the discharge liquid flow path 41. At this time, when a pressure difference is generated between the first discharge liquid chamber 31 and the first moisturizing liquid chamber 32, the liquid may seep into the first moisture permeable membrane 30. In this regard, according to the above-mentioned structure, the discharge liquid and air are stored in the first discharge liquid chamber 31, and the moisturizing liquid and air are stored in the first moisturizing liquid chamber 32. The air can move between the first discharge liquid chamber 31 and the first moisturizing liquid chamber 32. Therefore, even if the pressure variation mechanism 51 varies the pressure of the first discharge liquid chamber 31 or varies the pressure of the first moisturizing liquid chamber 32, it is difficult to generate a pressure difference between the first discharge liquid chamber 31 or the first moisturizing liquid chamber 32 and the first gap 30G. Thus, the risk of liquid seeping into the first moisture-permeable membrane 30 is reduced.

[0123] (4) The first connection end 42 and the second connection end 43 are connected to the first ejection liquid chamber 31. According to the above structure, the pressure in the first storage body 26 is changed by the pressure changing mechanism 51, and the ejection liquid flows in the ejection liquid flow path 41. As a result, the ejection liquid stored in the first storage body 26 circulates through the ejection liquid flow path 41. Through the circulation of the ejection liquid, moisture is supplied from the moisturizing liquid to the entire ejection liquid. Therefore, the moisturizing liquid can effectively moisturize the ejection liquid.

[0124] (5) The ejection portion 12 is located in the ejection liquid flow path 41. According to the above configuration, the ejection portion 12 ejects the ejection liquid that is effectively moisturized by the moisturizing liquid. Therefore, the ejection portion 12 can eject the ejection liquid appropriately.

[0125] (6) The pressure changing mechanism 51 includes a first changing portion 52 for changing the pressure in the first reservoir 26 and a second changing portion 53 for changing the pressure in the second reservoir 27. According to the above configuration, the pressure changing mechanism 51 changes the pressure in the first reservoir 26 and the pressure in the second reservoir 27, so that the ejection liquid circulates in the ejection liquid flow path 41. Thus, the circulated ejection liquid is moisturized by the moisturizing liquid.

[0126] (7) The liquid flow mechanism 21 includes the stirring portion 61 for stirring the moisturizing liquid stored in the first moisturizing liquid chamber 32. According to the above configuration, the moisturizing liquid is stirred by the stirring portion 61, thereby reducing the risk of the moisturizing liquid concentration increasing.

[0127] (8) The stirring section 61 includes a stirring flow path 62 and a stirring pump 65. The stirring flow path 62 circulates the moisturizing liquid stored in the first moisturizing liquid chamber 32. The stirring pump 65 is located in the stirring flow path 62. According to the above structure, the moisturizing liquid stored in the first moisturizing liquid chamber 32 circulates in the stirring flow path 62 by driving the stirring pump 65. As a result, the moisturizing liquid stored in the first moisturizing liquid chamber 32 is stirred. Therefore, the risk of the moisturizing liquid concentration increasing is reduced.

[0128] Second embodiment

[0129] Next, a second embodiment of the liquid ejection device 11 will be described. The second embodiment is different from the first embodiment in the structure of the pressure varying mechanism 51. In the second embodiment, the differences from the first embodiment will be mainly described.

[0130] like Figure 3 As shown, the first variable section 52 includes a first atmospheric release valve 58. The first variable section 52 changes the pressure in the first reservoir 26 to atmospheric pressure through the first atmospheric release valve 58. The second variable section 53 includes a second variable pump 55, a second pressure sensor 57, and a second atmospheric release valve 59. The second variable pump 55 pressurizes the second reservoir 27. The second variable pump 55 pressurizes the second reservoir 27, and the ejection liquid flows from the second reservoir 27 to the ejection section 12. As a result, the ejection liquid flows from the ejection section 12 to the first reservoir 26. When the liquid delivery pump 60 is driven, the ejection liquid flows from the first reservoir 26 to the second reservoir 27. In this way, the ejection liquid can be circulated by the second variable pump 55 and the liquid delivery pump 60. However, in this case, the negative pressure in the ejection section 12 is not maintained when the ejection liquid circulates. Therefore, in this example, it is difficult to circulate the ejection liquid while maintaining the negative pressure in the ejection section 12. Therefore, when the discharge liquid is circulated by the second variable pump 55 and the liquid feeding pump 60 , the discharge liquid may be circulated at a timing other than during printing.

[0131] The liquid flow mechanism 21 may also include a differential pressure valve. For example, the liquid flow mechanism 21 may also include a first differential pressure valve 71 and a second differential pressure valve 72. The first differential pressure valve 71 and the second differential pressure valve 72 are located in the first connecting flow path 44. Specifically, the first differential pressure valve 71 is located between the second storage body 27 and the ejection part 12 in the first connecting flow path 44. The second differential pressure valve 72 is located between the ejection part 12 and the first storage body 26 in the first connecting flow path 44.

[0132] The differential pressure valve is configured to open and close by the pressure difference with the atmospheric pressure. The first differential pressure valve 71 opens when the pressure in the ejection portion 12 is lower than a predetermined value, for example, when the amount of ejected liquid in the ejection portion 12 decreases. The second differential pressure valve 72 opens when the pressure in the ejection portion 12 exceeds a predetermined value, for example, when the amount of ejected liquid in the ejection portion 12 increases. Thus, the ejection portion 12 is maintained at a negative pressure.

[0133] The pressure in the ejection portion 12 when the first differential pressure valve 71 is opened may be different from the pressure in the ejection portion 12 when the second differential pressure valve 72 is opened. For example, the pressure in the ejection portion 12 when the first differential pressure valve 71 is opened may be greater than the pressure in the ejection portion 12 when the second differential pressure valve 72 is opened. Thus, the ejection liquid flows from the inlet path 15 toward the outlet path 19. Therefore, when the ejection liquid is circulated by the second variable pump 55 and the liquid delivery pump 60, the ejection liquid can be circulated while maintaining the inside of the ejection portion 12 at a negative pressure by the differential pressure valve.

[0134] The liquid flow mechanism 21 may also maintain the inside of the ejection portion 12 at a negative pressure by the water head difference. In this case, for example, the ejection portion 12 is arranged so that the nozzle surface 14 is located above the ejection liquid surface of the first storage body 26. Thus, when the ejection liquid is circulated by the second variable pump 55 and the liquid delivery pump 60, the ejection liquid can be circulated while maintaining the inside of the ejection portion 12 at a negative pressure.

[0135] The pressure changing mechanism 51 may also include a supply pump 73. The supply pump 73 is located in the ejection liquid supply flow path 35. When the supply pump 73 is driven, the ejection liquid is supplied from the ejection liquid supply source 22 to the first storage body 26. The pressure changing mechanism 51 may include the supply pump 73 when it does not include a structure for decompressing the inside of the first storage body 26. In this example, water is supplied from the water supply source 23 to the first storage body 26 by driving the stirring pump 65. In addition, the pressure changing mechanism 51 may include the supply pump 73 when it includes a structure for decompressing the inside of the first storage body 26.

[0136] Third embodiment

[0137] Next, a third embodiment of the liquid ejection device 11 will be described. The third embodiment is different from the first embodiment in the structure of the pressure varying mechanism 51. In the third embodiment, the differences from the first embodiment will be mainly described.

[0138] like Figure 4As shown, the second variable section 53 has a second atmospheric opening valve 59. The second variable section 53 changes the pressure in the second storage body 27 to the atmospheric pressure through the second atmospheric opening valve 59. The first variable section 52 has a first variable pump 54, a first pressure sensor 56, and a first atmospheric opening valve 58. The first variable pump 54 depressurizes the first storage body 26. The first variable pump 54 depressurizes the first storage body 26, and the ejection liquid flows from the ejection section 12 to the first storage body 26. Along with this, the ejection liquid flows from the second storage body 27 to the ejection section 12. The ejection liquid flows from the first storage body 26 to the second storage body 27 by driving the liquid delivery pump 60. In this way, the ejection liquid can also circulate through the first variable pump 54 and the liquid delivery pump 60.

[0139] Fourth embodiment

[0140] Next, a fourth embodiment of the liquid ejection device 11 will be described. The third embodiment is different from the first embodiment in the structure of the pressure varying mechanism 51. In the fourth embodiment, the differences from the first embodiment will be mainly described.

[0141] like Figure 5 As shown, the pressure changing mechanism 51 has a relay. Specifically, the pressure changing mechanism 51 has a first relay 74 and a second relay 75. The relay is connected to the storage body. The relay stores air. The relay communicates with the upper part of the storage body. Therefore, air can flow in and out of the relay and the storage body. The first relay 74 is connected to the first storage body 26. Air can flow in and out of the first relay 74 and the first storage body 26. The second relay 75 is connected to the second storage body 27. Air can flow in and out of the second relay 75 and the second storage body 27.

[0142] The first pressure sensor 56 is connected to the first relay body 74. The first pressure sensor 56 detects the pressure in the first relay body 74. The first pressure sensor 56 detects the pressure in the first storage body 26 by detecting the pressure in the first relay body 74. The second pressure sensor 57 is connected to the second relay body 75. The second pressure sensor 57 detects the pressure in the second relay body 75. The second pressure sensor 57 detects the pressure in the second storage body 27 by detecting the pressure in the second relay body 75.

[0143] The first atmosphere opening valve 58 is connected to the first relay body 74. The first atmosphere opening valve 58 allows the first relay body 74 to communicate with the atmosphere. The first atmosphere opening valve 58 allows the first storage body 26 to communicate with the atmosphere by allowing the first relay body 74 to communicate with the atmosphere. The second atmosphere opening valve 59 is connected to the second relay body 75. The second atmosphere opening valve 59 allows the second relay body 75 to communicate with the atmosphere. The second atmosphere opening valve 59 allows the second storage body 27 to communicate with the atmosphere by allowing the second relay body 75 to communicate with the atmosphere.

[0144] The pressure changing mechanism 51 includes a pressure regulating valve. Specifically, the pressure changing mechanism 51 includes a first pressure regulating valve 76 and a second pressure regulating valve 77. The first pressure regulating valve 76 is connected to the first relay body 74. The first pressure regulating valve 76 is connected to the first storage body 26 through the first relay body 74. The second pressure regulating valve 77 is connected to the second relay body 75. The second pressure regulating valve 77 is connected to the second storage body 27 through the second relay body 75.

[0145] The pressure regulating valve is a valve that regulates the pressure in the storage body. Specifically, the pressure regulating valve regulates the pressure in the storage body by regulating the pressure in the relay body. In one example, the pressure regulating valve is, for example, a solenoid valve. The pressure regulating valve is opened and closed based on the detection result of the pressure sensor, for example. Specifically, the opening degree of the pressure regulating valve is determined by the detection result of the pressure sensor. The first pressure regulating valve 76 is opened and closed based on the detection result of the first pressure sensor 56. For example, the first pressure regulating valve 76 is opened and closed so that the pressure in the first relay body 74 does not fall below a predetermined value. Thus, the risk of the pressure in the first storage body 26 becoming too low is reduced. The second pressure regulating valve 77 is opened and closed based on the detection result of the second pressure sensor 57. The second pressure regulating valve 77 is opened and closed so that the pressure in the second relay body 75 does not exceed a predetermined value. Thus, the risk of the pressure in the second storage body 27 becoming too high is reduced. The predetermined value of the first pressure regulating valve 76 may be different from the predetermined value of the second pressure regulating valve 77.

[0146] The pressure changing mechanism 51 includes a common pump 78. The common pump 78 is connected to the first relay body 74 and the second relay body 75. The common pump 78 depressurizes the first relay body 74. The common pump 78 depressurizes the first storage body 26 by depressurizing the first relay body 74. The common pump 78 pressurizes the second relay body 75. The common pump 78 pressurizes the second storage body 27 by pressurizing the second relay body 75.

[0147] When the common pump 78 is driven, the pressure in the first reservoir 26 is reduced. When the common pump 78 is driven, the pressure in the second reservoir 27 is increased. As a result, the ejection liquid flows from the second reservoir 27 to the first reservoir 26 through the first connecting flow path 44. In this way, the ejection liquid can circulate through the common pump 78 and the liquid delivery pump 60. In this example, the first variable portion 52 includes a first pressure sensor 56, a first atmospheric release valve 58, a first relay 74, a first pressure regulating valve 76, and a common pump 78. The second variable portion 53 includes a second pressure sensor 57, a second atmospheric release valve 59, a second relay 75, a second pressure regulating valve 77, and a common pump 78.

[0148] Fifth embodiment

[0149] Next, a fifth embodiment of the liquid ejection device 11 will be described. The fifth embodiment is different from the first embodiment in the structure of the pressure varying mechanism 51. In the fifth embodiment, the differences from the first embodiment will be mainly described.

[0150] like Figure 6 As shown, the pressure changing mechanism 51 has a regulator. Specifically, the pressure changing mechanism 51 has a first regulator 79 and a second regulator 80. The first regulator 79 is connected to the first reservoir 26. The first regulator 79 is connected to the first variable pump 54. The first regulator 79 is located between the first reservoir 26 and the first variable pump 54. The second regulator 80 is connected to the second reservoir 27. The second regulator 80 is connected to the second variable pump 55. The second regulator 80 is located between the second reservoir 27 and the second variable pump 55.

[0151] The regulator adjusts the pressure in the storage body. The first regulator 79 adjusts the pressure in the first storage body 26. Thus, the first variable pump 54 can reduce the pressure in the first storage body 26 so that the inside of the ejection part 12 is maintained at a predetermined negative pressure. The second regulator 80 adjusts the pressure in the second storage body 27. Thus, the second variable pump 55 can increase the pressure in the second storage body 27 so that the inside of the ejection part 12 is maintained at a predetermined negative pressure. In this example, the first variable part 52 includes the first variable pump 54 and the first regulator 79. The second variable part 53 includes the second variable pump 55 and the second regulator 80.

[0152] Sixth embodiment

[0153] Next, a sixth embodiment of the liquid ejection device 11 will be described. The sixth embodiment is different from the first embodiment in the structure of the pressure varying mechanism 51. In the sixth embodiment, the differences from the first embodiment will be mainly described.

[0154] like Figure 7 As shown, the pressure changing mechanism 51 has a switching valve. Specifically, the pressure changing mechanism 51 has a first switching valve 81 and a second switching valve 82. The first switching valve 81 is connected to the first reservoir 26. Specifically, the first switching valve 81 is located between the first reservoir 26 and the first atmospheric opening valve 58. The first switching valve 81 is opened and closed. When the first switching valve 81 is opened, the first reservoir 26 is connected to the first atmospheric opening valve 58. The second switching valve 82 is connected to the second reservoir 27. Specifically, the second switching valve 82 is located between the second reservoir 27 and the second atmospheric opening valve 59. The second switching valve 82 is opened and closed. When the second switching valve 82 is opened, the second reservoir 27 is connected to the second atmospheric opening valve 59.

[0155] The pressure varying mechanism 51 includes a variable pump. Specifically, the pressure varying mechanism 51 includes a first variable pump 54 and a second variable pump 55. In this example, the variable pump is a cylinder pump. The first variable pump 54 is connected to the first reservoir 26. Specifically, the first variable pump 54 is connected to the first reservoir 26 via the first switching valve 81. Therefore, the first variable pump 54 communicates with the first reservoir 26 when the first switching valve 81 is opened. The first variable pump 54 is connected to the first atmospheric opening valve 58. Therefore, the first variable pump 54 can inhale or exhaust air through the first atmospheric opening valve 58. The second variable pump 55 is connected to the second reservoir 27. Specifically, the second variable pump 55 is connected to the second reservoir 27 via the second switching valve 82. Therefore, the second variable pump 55 communicates with the second reservoir 27 when the second switching valve 82 is opened. The second variable pump 55 is connected to the second atmospheric opening valve 59. Therefore, the second variable pump 55 can inhale or exhaust air through the second atmospheric opening valve 59.

[0156] The first variable pump 54 sucks air when the first switching valve 81 is open. At this time, the first variable pump 54 decompresses the first storage body 26 based on the first pressure sensor 56. Next, the first variable pump 54 exhausts air when the first switching valve 81 is closed. At this time, the first variable pump 54 exhausts air through the first atmosphere release valve 58. In this example, the first variable unit 52 includes the first variable pump 54, the first pressure sensor 56, the first atmosphere release valve 58, and the first switching valve 81.

[0157] The second variable pump 55 sucks air when the second switching valve 82 is closed. At this time, the second variable pump 55 sucks air through the second atmosphere release valve 59. Then, the second variable pump 55 exhausts air when the second switching valve 82 is opened. At this time, the second variable pump 55 pressurizes the inside of the second storage body 27 based on the second pressure sensor 57. In this example, the second variable part 53 includes the second variable pump 55, the second pressure sensor 57, the second atmosphere release valve 59 and the second switching valve 82. In this way, the ejected liquid can also circulate through the first variable pump 54, the second variable pump 55 and the liquid delivery pump 60.

[0158] Seventh embodiment

[0159] Next, a seventh embodiment of the liquid ejection device 11 will be described. The seventh embodiment is different from the first embodiment in the structure of the pressure varying mechanism 51. In the seventh embodiment, the differences from the first embodiment will be mainly described.

[0160] like Figure 8As shown, the pressure changing mechanism 51 includes a pressure regulating valve. Specifically, the pressure changing mechanism 51 includes a first pressure regulating valve 76 and a second pressure regulating valve 77. The pressure regulating valve is configured to adjust the pressure in the storage body in the same manner as in the fourth embodiment. The first pressure regulating valve 76 is connected to the first storage body 26. The first pressure regulating valve 76 is opened and closed so that the pressure in the first storage body 26 does not fall below a predetermined value. The first pressure regulating valve 76 is opened and closed based on the detection result of the first pressure sensor 56. The second pressure regulating valve 77 is connected to the second storage body 27. The second pressure regulating valve 77 is opened and closed so that the pressure in the second storage body 27 does not exceed a predetermined value. The second pressure regulating valve 77 is opened and closed based on the detection result of the second pressure sensor 57.

[0161] The pressure changing mechanism 51 does not have a pressure changing pump. Therefore, the pressure changing mechanism 51 changes the pressure in the reservoir by the liquid feeding pump 60. When the liquid feeding pump 60 is driven, the ejection liquid is sent from the first reservoir 26 to the second reservoir 27. At this time, the amount of ejection liquid in the first reservoir 26 decreases, and the amount of ejection liquid in the second reservoir 27 increases. When the amount of ejection liquid in the reservoir changes, the pressure in the reservoir changes. That is, when the liquid feeding pump 60 is driven, the pressure in the first reservoir 26 is reduced, and the pressure in the second reservoir 27 is increased. By reducing the pressure in the first reservoir 26, the ejection liquid flows from the ejection part 12 to the first reservoir 26. By increasing the pressure in the second reservoir 27, the ejection liquid flows from the second reservoir 27 to the ejection part 12. In this way, the ejection liquid can be circulated by the liquid feeding pump 60. In this example, the first variable unit 52 includes a first pressure sensor 56, a first atmosphere release valve 58, a liquid delivery pump 60, and a first pressure regulating valve 76. The second variable unit 53 includes a second pressure sensor 57, a second atmosphere release valve 59, a liquid delivery pump 60, and a second pressure regulating valve 77.

[0162] Eighth embodiment

[0163] Next, an eighth embodiment of the liquid ejection device 11 will be described. The eighth embodiment is different from the first embodiment in the structure of the liquid flow mechanism 21. In the seventh embodiment, the differences from the first embodiment will be mainly described.

[0164] like Fig. 9 As shown, the liquid flow mechanism 21 has a differential pressure valve. Specifically, the liquid flow mechanism 21 has a first differential pressure valve 71 and a second differential pressure valve 72. The differential pressure valve is the same as that of the second embodiment. The negative pressure in the ejection portion 12 is maintained by the first differential pressure valve 71 and the second differential pressure valve 72.

[0165] The liquid flow mechanism 21 has a third liquid storage portion 83. The third liquid storage portion 83 is configured to store the ejection liquid, or to store the ejection liquid and the moisturizing liquid. In this example, the third liquid storage portion 83 stores the ejection liquid.

[0166] The third liquid storage portion 83 includes a third storage body 84. The third storage body 84 defines a third storage chamber 85. The third liquid storage portion 83 does not include a moisture permeable membrane similarly to the second liquid storage portion 25.

[0167] The third storage body 84 is connected to the first storage body 26 and the second storage body 27. In detail, the third storage body 84 is located in the second connecting flow path 45. The third storage chamber 85 is communicated with the first storage chamber 28 and the second storage chamber 29. In detail, the third storage chamber 85 is communicated with the first ejection liquid chamber 31 and the second storage chamber 29.

[0168] The pressure changing mechanism 51 includes a variable pump. The pressure changing mechanism 51 includes a first variable pump 54 and a second variable pump 55. The first variable pump 54 is connected to the first reservoir 26 and the third reservoir 84. The first variable pump 54 depressurizes the first reservoir 26 and the third reservoir 84. The second variable pump 55 is connected to the second reservoir 27 and the third reservoir 84. The second variable pump 55 pressurizes the second reservoir 27 and the third reservoir 84.

[0169] The pressure changing mechanism 51 has a switching valve. The pressure changing mechanism 51 has a first switching valve 81 and a second switching valve 82, similarly to the sixth embodiment. The first switching valve 81 is connected to the first variable pump 54 and the third reservoir 84. The first switching valve 81 is located between the first variable pump 54 and the third reservoir 84. When the first switching valve 81 is opened, the first variable pump 54 is communicated with the third reservoir 84. The second switching valve 82 is connected to the second variable pump 55 and the third reservoir 84. The second switching valve 82 is located between the second variable pump 55 and the third reservoir 84. When the second switching valve 82 is opened, the second variable pump 55 is communicated with the third reservoir 84.

[0170] The pressure varying mechanism 51 is configured so that, when the first variable pump 54 reduces the pressure in the first reservoir 26 and the third reservoir 84, the pressure in the first reservoir 26 becomes higher than the pressure in the third reservoir 84. Thus, since a pressure difference is generated between the first reservoir 26 and the third reservoir 84, the ejected liquid flows from the first reservoir 26 to the third reservoir 84 through the second connecting flow path 45.

[0171] The pressure varying mechanism 51 is configured so that, when the second variable pump 55 pressurizes the inside of the second reservoir 27 and the inside of the third reservoir 84, the pressure inside the third reservoir 84 becomes higher than the pressure inside the second reservoir 27. Thus, since a pressure difference is generated between the inside of the third reservoir 84 and the inside of the second reservoir 27, the ejected liquid flows from the third reservoir 84 to the second reservoir 27 through the second connecting flow path 45.

[0172] The pressure changing mechanism 51 may also have a resistance portion. Specifically, the pressure changing mechanism 51 has a first resistance portion 86 and a second resistance portion 87. The resistance portion is configured to be a resistance to the pressure change of the variable pump. The resistance portion is, for example, a capillary tube. The resistance portion is not limited to a capillary tube, and may be, for example, a valve. The resistance portion is located between the variable pump and the reservoir. The first resistance portion 86 is located between the first variable pump 54 and the first reservoir 26. That is, the first variable pump 54 reduces the pressure in the first reservoir 26 through the first resistance portion 86. The second resistance portion 87 is located between the second variable pump 55 and the second reservoir 27. That is, the second variable pump 55 pressurizes the second reservoir 27 through the second resistance portion 87.

[0173] It is difficult for the first variable pump 54 to depressurize the first reservoir 26 through the first resistance portion 86. Therefore, when the first variable pump 54 is driven, a pressure difference is generated between the first reservoir 26 and the third reservoir 84. As a result, the ejection liquid flows from the first reservoir 26 to the third reservoir 84. In this example, the first variable portion 52 includes the first variable pump 54, the first switching valve 81, and the first resistance portion 86. It is difficult for the second variable pump 55 to pressurize the second reservoir 27 through the second resistance portion 87. Therefore, when the second variable pump 55 is driven, a pressure difference is generated between the second reservoir 27 and the third reservoir 84. As a result, the ejection liquid flows from the third reservoir 84 to the second reservoir 27. In this example, the second variable portion 53 includes the second variable pump 55, the second switching valve 82, and the second resistance portion 87. In this way, the ejection liquid may flow from the first reservoir 26 to the second reservoir 27 through the first variable pump 54 and the second variable pump 55 without being limited to the liquid feeding pump 60.

[0174] The liquid flow mechanism 21 may have one or more check valves 88. The check valve 88 is a valve that allows liquid to flow in one direction and restricts liquid from flowing in the opposite direction. The liquid flow mechanism 21 has, for example, two check valves 88. The check valves 88 are located in the second connecting flow path 45. In detail, the two check valves 88 are located between the first reservoir 26 and the third reservoir 84 and between the second reservoir 27 and the third reservoir 84 in the second connecting flow path 45, respectively. The check valves 88 reduce the risk of backflow of the ejected liquid through the second connecting flow path 45. That is, the check valves 88 reduce the risk of the ejected liquid flowing from the third reservoir 84 to the first reservoir 26 or the ejected liquid flowing from the second reservoir 27 to the third reservoir 84. The check valves 88 are located in the ejected liquid flow path 41, thereby regulating the flow of the ejected liquid circulating in the ejected liquid flow path 41.

[0175] Ninth embodiment

[0176] Next, a ninth embodiment of the liquid ejection device 11 will be described. The ninth embodiment is different from the first embodiment in the structure of the liquid flow mechanism 21. In the ninth embodiment, the differences from the first embodiment will be mainly described.

[0177] like Fig.10 As shown, the liquid flow mechanism 21 has a differential pressure valve. Specifically, the liquid flow mechanism 21 has a first differential pressure valve 71 and a second differential pressure valve 72. The differential pressure valve is the same as that of the second embodiment and the eighth embodiment. The negative pressure in the ejection portion 12 can be maintained by the first differential pressure valve 71 and the second differential pressure valve 72.

[0178] The second liquid storage part 25 is configured to store the ejection liquid and the moisturizing liquid. The second liquid storage part 25 has a second moisture permeable membrane 90. The second moisture permeable membrane 90 is attached to the second storage body 27. The second moisture permeable membrane 90 divides the second storage body 27 into a second ejection liquid chamber 91 and a second moisturizing liquid chamber 92. The ejection liquid is stored in the second ejection liquid chamber 91. The moisturizing liquid is stored in the second moisturizing liquid chamber 92. In the second moisture permeable membrane 90, a plurality of pores are formed similarly to the first moisture permeable membrane 30. In addition, the second moisture permeable membrane 90 defines a gap connected to the plurality of pores.

[0179] The second moisture permeable membrane 90 has a second upper end 93 and a second lower end 94. The second lower end 94 is attached to the second storage body 27. The second upper end 93 is located above the ejection liquid level of the second ejection liquid chamber 91 and the moisturizing liquid level of the second moisturizing liquid chamber 92. The second storage body 27 stores the ejection liquid and the moisturizing liquid in such a manner that the second upper end 93 is located above the ejection liquid level of the second ejection liquid chamber 91 and the moisturizing liquid level of the second moisturizing liquid chamber 92. In one example, the second moisture permeable membrane 90 completely divides the interior of the second storage body 27. That is, the second upper end 93 and the second lower end 94 are attached to the second storage body 27.

[0180] The liquid flow mechanism 21 includes a third liquid storage portion 83. The third liquid storage portion 83 is configured to store the ejection liquid and the moisturizing liquid in the same manner as the second liquid storage portion 25. The third liquid storage portion 83 includes a third storage body 84 and a third moisture permeable membrane 95. The third moisture permeable membrane 95 is attached to the third storage body 84. The third moisture permeable membrane 95 divides the interior of the third storage body 84 into a third ejection liquid chamber 96 and a third moisturizing liquid chamber 97. The ejection liquid is stored in the third ejection liquid chamber 96. The moisturizing liquid is stored in the third moisturizing liquid chamber 97. In the third moisture permeable membrane 95, a plurality of pores are formed in the same manner as the first moisture permeable membrane 30. In addition, the third moisture permeable membrane 95 defines a gap connected to the plurality of pores.

[0181] The third moisture permeable membrane 95 has a third upper end 98 and a third lower end 99. The third lower end 99 is attached to the third storage body 84. The third upper end 98 is located above the ejection liquid surface of the third ejection liquid chamber 96 and the moisturizing liquid surface of the third moisturizing liquid chamber 97. The third storage body 84 stores the ejection liquid and the moisturizing liquid in such a manner that the third upper end 98 is located above the ejection liquid surface of the third ejection liquid chamber 96 and the moisturizing liquid surface of the third moisturizing liquid chamber 97. In one example, the third moisture permeable membrane 95 completely divides the inside of the third storage body 84. That is, the third upper end 98 and the third lower end 99 are attached to the third storage body 84.

[0182] The third reservoir 84 is connected to the first reservoir 26 and the second reservoir 27. Specifically, the third reservoir 84 is located in the second connecting flow path 45. The third ejection liquid chamber 96 communicates with the first ejection liquid chamber 31 and the second ejection liquid chamber 91.

[0183] The stirring section 61 has a stirring flow path 62. The stirring flow path 62 has a first circulation flow path 101 and a second circulation flow path 102. The first circulation flow path 101 is connected to the first liquid storage section 24 and the second liquid storage section 25. In detail, the first circulation flow path 101 is connected to the first storage body 26 and the second storage body 27. The first circulation flow path 101 is connected to the first moisturizing liquid chamber 32 and the second moisturizing liquid chamber 92. In one example, the first circulation flow path 101 has a second end 64. The second circulation flow path 102 is connected to the first liquid storage section 24 and the second liquid storage section 25. In detail, the second circulation flow path 102 is connected to the first storage body 26 and the second storage body 27. In one example, the second circulation flow path 102 has a first end 63. The third storage body 84 is located in the second circulation flow path 102. Therefore, the second circulation flow path 102 is connected to the first moisturizing liquid chamber 32, the second moisturizing liquid chamber 92, and the third moisturizing liquid chamber 97.

[0184] The liquid flow mechanism 21 has one or more check valves 88. In one example, the liquid flow mechanism 21 has four check valves 88. Two of the four check valves 88 are located in the ejection liquid flow path 41 as in the eighth embodiment. The remaining two check valves 88 are located in the stirring flow path 62. In detail, the two check valves 88 are located in the second circulation flow path 102. The two check valves 88 are located between the first reservoir 26 and the third reservoir 84 and between the second reservoir 27 and the third reservoir 84 in the second circulation flow path 102, respectively. The check valves 88 reduce the risk of the moisturizing liquid flowing from the third reservoir 84 to the first reservoir 26 or the moisturizing liquid flowing from the second reservoir 27 to the third reservoir 84. The check valves 88 are located in the stirring flow path 62 to regulate the flow of the moisturizing liquid circulating in the stirring flow path 62.

[0185] The pressure varying mechanism 51 includes a first varying pump 54, a second varying pump 55, a first switching valve 81, a second switching valve 82, a first resistance portion 86, and a second resistance portion 87, similarly to the eighth embodiment. The first varying portion 52 and the second varying portion 53 are similar to those of the eighth embodiment.

[0186] The first variable displacement pump 54 depressurizes the first reservoir 26 and the third reservoir 84. At this time, the pressure in the first reservoir 26 becomes higher than the pressure in the third reservoir 84 due to the first resistance portion 86. As a result, the spray liquid and the moisturizing liquid flow from the first reservoir 26 to the third reservoir 84. The second variable displacement pump 55 pressurizes the second reservoir 27 and the third reservoir 84. At this time, the pressure in the third reservoir 84 becomes higher than the pressure in the second reservoir 27 due to the second resistance portion 87. As a result, the spray liquid and the moisturizing liquid flow from the third reservoir 84 to the second reservoir 27. In addition, the first variable displacement pump 54 depressurizes the first reservoir 26 and the second variable displacement pump 55 pressurizes the second reservoir 27, so that the spray liquid and the moisturizing liquid flow from the second reservoir 27 to the first reservoir 26. In this way, the liquid circulates through the first variable displacement pump 54 and the second variable displacement pump 55. Therefore, in the ninth embodiment, the pressure varying mechanism 51 also serves as the stirring portion 61 .

[0187] Tenth embodiment

[0188] Next, a tenth embodiment of the liquid ejection device 11 will be described. The tenth embodiment is different from the first embodiment in the position of the pressure sensor. In the tenth embodiment, the differences from the first embodiment will be mainly described.

[0189] like Fig.11 As shown, the first pressure sensor 56 and the second pressure sensor 57 are located in the first connecting flow path 44. Specifically, the first pressure sensor 56 is located between the ejection portion 12 and the first reservoir 26 in the first connecting flow path 44. The second pressure sensor 57 is located between the second reservoir 27 and the ejection portion 12 in the first connecting flow path 44. The first pressure sensor 56 detects the pressure in the first reservoir 26 through the first connecting flow path 44. The second pressure sensor 57 detects the pressure in the second reservoir 27 through the first connecting flow path 44. Based on the detection result of the first pressure sensor 56, the first variable pump 54 depressurizes the first reservoir 26. Based on the detection result of the second pressure sensor 57, the second variable pump 55 pressurizes the second reservoir 27. As a result, the ejection liquid circulates in a state where the ejection portion 12 is maintained at a negative pressure.

[0190] Eleventh Embodiment

[0191] Next, an eleventh embodiment of the liquid ejection device 11 will be described. The eleventh embodiment is different from the first embodiment in the structure of the liquid flow mechanism 21. In the eleventh embodiment, the differences from the first embodiment will be mainly described.

[0192] like Fig.12 As shown, the liquid flow mechanism 21 has a relay tank 103. The relay tank 103 is connected to the ejection liquid flow path 41. In detail, the relay tank 103 is connected to the first connection flow path 44 in parallel with the ejection part 12. Therefore, the ejection liquid enters and exits the relay tank 103 in the same manner as the ejection part 12. The ejection liquid circulates in the ejection liquid flow path 41 by passing through the ejection part 12 or the relay tank 103.

[0193] The pressure changing mechanism 51 has a pressure sensor. In detail, the pressure changing mechanism 51 has a relay pressure sensor 104. The relay pressure sensor 104 is connected to the relay tank 103. The relay pressure sensor 104 detects the pressure in the relay tank 103. The pressure in the relay tank 103 corresponds to the pressure in the ejection part 12. Therefore, the relay pressure sensor 104 detects the pressure in the ejection part 12 by detecting the pressure in the relay tank 103. In detail, the relay pressure sensor 104 detects the pressure in the ejection part 12 based on the pressure in the relay tank 103 by referring to the corresponding data. The corresponding data is data in which the pressure in the relay tank 103 corresponds to the pressure in the ejection part 12. The corresponding data can also be stored by the control unit 67.

[0194] The first variable displacement pump 54 depressurizes the first reservoir 26 based on the detection result of the relay pressure sensor 104. The second variable displacement pump 55 pressurizes the second reservoir 27 based on the detection result of the relay pressure sensor 104. Thus, the ejection liquid circulates in the ejection portion 12 while being maintained at a negative pressure.

[0195] Twelfth Embodiment

[0196] Next, a twelfth embodiment of the liquid ejection device 11 will be described. The twelfth embodiment is different from the first embodiment in the structure of the pressure varying mechanism 51. In the twelfth embodiment, the differences from the first embodiment will be mainly described.

[0197] like Fig.13As shown in FIG. 1 , the pressure changing mechanism 51 includes a differential pressure regulating valve instead of a pressure sensor. Specifically, the pressure changing mechanism 51 includes a first differential pressure regulating valve 105 instead of the first pressure sensor 56. The pressure changing mechanism 51 includes a second differential pressure regulating valve 106 instead of the second pressure sensor 57. The differential pressure regulating valve is a valve that is opened and closed by the pressure difference between the pressure in the reservoir and the atmospheric pressure. The first differential pressure regulating valve 105 is opened and closed by the pressure difference between the pressure in the first reservoir 26 and the atmospheric pressure. The second differential pressure regulating valve 106 is opened and closed by the pressure difference between the pressure in the second reservoir 27 and the atmospheric pressure.

[0198] The first differential pressure regulating valve 105 is connected to the first reservoir 26. When the pressure in the first reservoir 26 is lower than a predetermined value, the first differential pressure regulating valve 105 is opened. Thus, the pressure in the first reservoir 26 is maintained not lower than the predetermined value. The first differential pressure regulating valve 105 controls the pressure in the first reservoir 26.

[0199] The second differential pressure regulating valve 106 is connected to the second reservoir 27. When the pressure in the second reservoir 27 exceeds a predetermined value, the second differential pressure regulating valve 106 opens. Thus, the pressure in the second reservoir 27 is maintained not to exceed the predetermined value. The second differential pressure regulating valve 106 controls the pressure in the second reservoir 27.

[0200] The pressure in the first storage body 26 and the pressure in the second storage body 27 are controlled by the first differential pressure regulating valve 105 and the second differential pressure regulating valve 106, respectively, so that the discharge liquid circulates in the discharge portion 12 while being maintained at a negative pressure.

[0201] Thirteenth Embodiment

[0202] Next, a thirteenth embodiment of the liquid ejection device 11 will be described. The thirteenth embodiment is different from the first embodiment in the structure of the pressure varying mechanism 51. In the thirteenth embodiment, the differences from the first embodiment will be mainly described.

[0203] like Fig.14 As shown in FIG. 1 , the pressure changing mechanism 51 includes a pressure differential valve instead of a pressure sensor. Specifically, the pressure changing mechanism 51 includes a first pressure differential valve 71 and a second pressure differential valve 72 instead of the first pressure sensor 56 and the second pressure sensor 57. The pressure differential valve is the same as that of the second embodiment, the eighth embodiment, and the ninth embodiment. The first pressure differential valve 71 and the second pressure differential valve 72 maintain the negative pressure in the ejection portion 12 regardless of the pressure in the first storage body 26 and the pressure in the second storage body 27. Thus, the ejection liquid circulates in a state where the ejection portion 12 is maintained at a negative pressure.

[0204] Fourteenth Embodiment

[0205] Next, a fourteenth embodiment of the liquid ejection device 11 will be described. The fourteenth embodiment is different from the first embodiment in the structure of the liquid flow mechanism 21. In the fourteenth embodiment, the differences from the first embodiment will be mainly described.

[0206] like Fig.15 As shown in FIG. 1 , the pressure changing mechanism 51 includes a supply pump 73. The supply pump 73 is the same as that of the second embodiment. The supply pump 73 is driven to supply the ejection liquid from the ejection liquid supply source 22 to the first storage body 26. In this example, the stirring pump 65 is driven to supply water from the water supply source 23 to the first storage body 26.

[0207] The liquid flow mechanism 21 is configured to deliver the ejection liquid from the first reservoir 26 to the ejection portion 12. That is, the first variable portion 52 delivers the ejection liquid from the first reservoir 26 to the ejection portion 12 by pressurizing the inside of the first reservoir 26. The liquid flow mechanism 21 is configured to deliver the ejection liquid from the ejection portion 12 to the second reservoir 27. That is, the second variable portion 53 delivers the ejection liquid from the ejection portion 12 to the second reservoir 27 by depressurizing the inside of the second reservoir 27. The liquid delivery pump 60 delivers the ejection liquid from the second reservoir 27 to the first reservoir 26.

[0208] The first variable pump 54 is a pressure pump. The first variable pump 54 pressurizes the first storage body 26 based on the first pressure sensor 56. The second variable pump 55 is a pressure reducing pump. The second variable pump 55 depressurizes the second storage body 27 based on the second pressure sensor 57. Thus, the ejection liquid circulates in a state where the ejection portion 12 is maintained at a negative pressure. That is, in the fourteenth embodiment, the flow of the ejection liquid circulating in the ejection liquid flow path 41 is in the opposite direction compared to the first embodiment.

[0209] Fifteenth Embodiment

[0210] Next, a fifteenth embodiment of the liquid ejection device 11 will be described. The fifteenth embodiment is different from the first embodiment in the structure of the liquid flow mechanism 21. In the fifteenth embodiment, the differences from the first embodiment will be mainly described.

[0211] like Fig.16 As shown, the liquid flow mechanism 21 has a second liquid storage part 25. The second liquid storage part 25 has a second storage body 27 and a second moisture permeable membrane 90 as in the ninth embodiment. The second moisture permeable membrane 90 divides the second storage chamber 29 into a second ejection liquid chamber 91 and a second moisturizing liquid chamber 92.

[0212] The second ejection liquid chamber 91 is communicated with the ejection liquid flow path 41. The second ejection liquid chamber 91 is communicated with the first connection flow path 44 and the second connection flow path 45. The ejection liquid circulates in the first ejection liquid chamber 31 and the second ejection liquid chamber 91 through the ejection liquid flow path 41.

[0213] The stirring section 61 has a stirring flow path 62. The stirring flow path 62 has a first circulation flow path 101 and a second circulation flow path 102 similarly to the ninth embodiment. The first circulation flow path 101 is connected to the first storage body 26 and the second storage body 27. The first circulation flow path 101 is communicated with the first moisturizing liquid chamber 32 and the second moisturizing liquid chamber 92. In one example, the first circulation flow path 101 has a second end 64. The second circulation flow path 102 is connected to the first storage body 26 and the second storage body 27. The second circulation flow path 102 is communicated with the first moisturizing liquid chamber 32 and the second moisturizing liquid chamber 92. In one example, the second circulation flow path 102 has a first end 63.

[0214] The stirring section 61 has a stirring pump 65. The stirring pump 65 is located in the second circulation flow path 102. When the stirring pump 65 is driven, the moisturizing liquid flows from the first moisturizing liquid chamber 32 to the second moisturizing liquid chamber 92 through the second circulation flow path 102. At this time, the moisturizing liquid flows from the second moisturizing liquid chamber 92 to the first moisturizing liquid chamber 32 through the first circulation flow path 101. In this way, the moisturizing liquid circulates in the stirring flow path 62.

[0215] The moisturizing liquid can also be circulated by the first variable pump 54, the second variable pump 55, and the stirring pump 65. The first variable pump 54 and the second variable pump 55 respectively change the pressure in the first reservoir 26 and the pressure in the second reservoir 27, so that the ejection liquid flows from the second ejection liquid chamber 91 to the first ejection liquid chamber 31 through the first connecting flow path 44. At this time, the moisturizing liquid flows from the second moisturizing liquid chamber 92 to the first moisturizing liquid chamber 32 through the first circulation flow path 101.

[0216] Change Example

[0217] The above-mentioned embodiment can be implemented by being modified as follows. The above-mentioned embodiment and the following modified examples can be implemented by being combined with each other within the scope of no technical contradiction.

[0218] The liquid flow mechanism 21 may include four or more liquid storage parts, and the liquid may be configured to circulate among the four or more liquid storage parts.

[0219] The liquid flow mechanism 21 may be configured such that the second liquid storage part 25 has a moisture permeable membrane and the third liquid storage part 83 does not have a moisture permeable membrane. The liquid flow mechanism 21 may be configured such that the third liquid storage part 83 has a moisture permeable membrane and the second liquid storage part 25 does not have a moisture permeable membrane.

[0220] The liquid ejected by the ejection unit 12 is not limited to ink, and may be, for example, a liquid in which particles of a functional material are dispersed or mixed in a liquid. For example, the ejection unit 12 may eject a liquid containing, in a dispersed or dissolved form, materials such as electrode materials or pixel materials used in the manufacture of liquid crystal displays, electroluminescent displays, and surface-emitting displays.

[0221] Sixteenth Embodiment

[0222] First, a sixteenth embodiment of the liquid ejecting device will be described.

[0223] like Fig.17 As shown, the liquid ejection device 111 is connected to a supply source 112. The supply source 112 contains the ejection liquid. The supply source 112 can be a box, a bag, etc. that can be detached from the liquid ejection device 111, or a tank that can replenish the ejection liquid. The supply source 112 can also be open to the atmosphere. The ejection liquid is supplied from the supply source 112 to the liquid ejection device 111.

[0224] The liquid ejection device 111 includes an ejection mechanism 113. The ejection mechanism 113 is a mechanism for ejecting the ejection liquid. The ejection mechanism 113 is connected to the supply source 112. The ejection liquid supplied from the supply source 112 flows in the ejection mechanism 113. The ejection mechanism 113 ejects the ejection liquid supplied from the supply source 112.

[0225] The ejection mechanism 113 includes an ejection unit 114 . The ejection unit 114 is configured to eject the ejection liquid onto the medium M11 . The ejection unit 114 is a so-called print head. The ejection unit 114 includes a nozzle face 116 in which one or more nozzles 115 are opened. The ejection unit 114 ejects the ejection liquid from the nozzles 115 .

[0226] The discharge portion 114 is provided with an introduction path 117, a common liquid chamber 118, and one or more independent liquid chambers 119. The introduction path 117, the common liquid chamber 118, and one or more independent liquid chambers 119 are spaces within the discharge portion 114 where the discharge liquid flows.

[0227] The introduction path 117 is a space for introducing the ejection liquid into the ejection portion 114. The common liquid chamber 118 is connected to the introduction path 117. The ejection liquid is introduced into the common liquid chamber 118 through the introduction path 117. One or more independent liquid chambers 119 are connected to the common liquid chamber 118. The ejection liquid is introduced into one or more independent liquid chambers 119 through the common liquid chamber 118. In the case where the ejection portion 114 forms a plurality of independent liquid chambers 119, the plurality of independent liquid chambers 119 are connected to the common liquid chamber 118. One independent liquid chamber 119 is connected to one nozzle 115. Therefore, the ejection portion 114 is provided with the same number of independent liquid chambers 119 as the number of nozzles 115. The ejection portion 114 ejects the ejection liquid from the nozzle 115 by applying pressure to the ejection liquid located in the independent liquid chamber 119.

[0228] The ejection portion 114 may also include a filter 120. In one example, the filter 120 is located in the inlet path 117. Specifically, the filter 120 is located at the end portion connected to the common liquid chamber 118 in the inlet path 117. The filter 120 captures and collects bubbles, foreign matter, etc. contained in the ejection liquid. Thus, the ejection liquid from which bubbles, foreign matter, etc. have been removed is supplied to the common liquid chamber 118 and the independent liquid chamber 119.

[0229] A guide path 121 may also be formed in the ejection portion 114. The guide path 121 is a space in the ejection portion 114 where the ejection liquid flows. The guide path 121 is a space for guiding the ejection liquid from the ejection portion 114. Therefore, the ejection liquid can flow in the ejection portion 114 from the introduction path 117 to the guide path 121. When the ejection liquid is retained for a long time, it is possible that viscosity increase or sedimentation occurs in the ejection liquid. By allowing the ejection liquid to flow in the ejection portion 114, the risk of viscosity increase or sedimentation occurring in the ejection liquid in the ejection portion 114 is reduced.

[0230] The derivation path 121 extends from the inlet path 117, the common liquid chamber 118, or the independent liquid chamber 119. In one example, the derivation path 121 extends from the common liquid chamber 118. Therefore, the ejected liquid flows in the order of the inlet path 117, the common liquid chamber 118, and the derivation path 121, thereby passing through the ejection portion 114. The derivation path 121 may extend from the inlet path 117 or from the independent liquid chamber 119. The derivation path 121 may also extend from the inlet path 117 in such a manner that the ejected liquid passes through the ejection portion 114 without passing through the filter 120.

[0231] The ejection portion 114 is usually maintained at a negative pressure. This is to form a curved liquid surface at the nozzle 115. As a result, the ejection portion 114 can properly eject the ejection liquid. Therefore, even when the ejection liquid flows from the inlet path 117 to the outlet path 121, the ejection portion 114 can be maintained at a negative pressure. When the negative pressure of the ejection portion 114 is released, the curved liquid surface may be destroyed. When the curved liquid surface is destroyed, it is necessary to form a curved liquid surface again at the nozzle 115.

[0232] The ejection mechanism 113 has one or more ejection liquid storage parts. In one example, the ejection mechanism 113 has a first ejection liquid storage part 123 and a second ejection liquid storage part 124. The ejection mechanism 113 may have three or more ejection liquid storage parts.

[0233] The ejection liquid storage portion stores the ejection liquid. The ejection liquid storage portion is connected to the supply source 112. Therefore, the ejection liquid is supplied from the supply source 112 to the ejection liquid storage portion. In one example, the first ejection liquid storage portion 123 is connected to the supply source 112. The second ejection liquid storage portion 124 is connected to the first ejection liquid storage portion 123. That is, the second ejection liquid storage portion 124 is connected to the supply source 112 through the first ejection liquid storage portion 123. The ejection liquid is supplied from the first ejection liquid storage portion 123 to the second ejection liquid storage portion 124. The first ejection liquid storage portion 123 is not limited to being supplied with the ejection liquid from the supply source 112, but may also be configured to be supplied with the ejection liquid from the second ejection liquid storage portion 124. The second ejection liquid storage portion 124 is not limited to being supplied with the ejection liquid from the first ejection liquid storage portion 123, but may also be configured to be directly supplied with the ejection liquid from the supply source 112.

[0234] The spray liquid storage portion defines a spray liquid chamber. The spray liquid chamber is a space for storing the spray liquid. The first spray liquid storage portion 123 defines a first spray liquid chamber 125. The second spray liquid storage portion 124 defines a second spray liquid chamber 126. In one example, the spray liquid storage portion stores air together with the spray liquid. Therefore, there is a liquid level of the spray liquid in the spray liquid storage portion. The spray liquid storage portion can also be filled with the spray liquid.

[0235] The ejection mechanism 113 has an ejection liquid flow path 128. The ejection liquid flow path 128 is a flow path in which the ejection liquid flows. The ejection liquid flow path 128 is connected to the supply source 112. The ejection liquid flow path 128 is connected to the ejection portion 114. The ejection liquid is supplied from the supply source 112 to the ejection portion 114 through the ejection liquid flow path 128.

[0236] The ejection liquid storage portion is located in the ejection liquid flow path 128. That is, the ejection liquid flow path 128 is connected to the ejection liquid storage portion. In one example, the first ejection liquid storage portion 123 and the second ejection liquid storage portion 124 are located in the middle of the ejection liquid flow path 128. The ejection liquid flow path 128 is connected to the first ejection liquid storage portion 123 and the second ejection liquid storage portion 124.

[0237] The ejection liquid flow path 128 has an ejection liquid supply flow path 129. The ejection liquid supply flow path 129 is connected to the supply source 112. The ejection liquid supply flow path 129 is connected to the ejection liquid storage portion. The ejection liquid is supplied from the supply source 112 to the ejection liquid storage portion through the ejection liquid supply flow path 129. In one example, the ejection liquid supply flow path 129 is connected to the supply source 112 and the first ejection liquid storage portion 123.

[0238] The ejection liquid flow path 128 has an ejection liquid flow path 130. The ejection liquid flow path 130 is connected to the ejection liquid storage portion. The ejection liquid flow path 130 is connected to the ejection portion 114. The ejection liquid is supplied from the ejection liquid storage portion to the ejection portion 114 through the ejection liquid flow path 130. In one example, the ejection liquid flow path 130 is connected to the ejection portion 114, the first ejection liquid storage portion 123, and the second ejection liquid storage portion 124. The ejection liquid flow path 130 is connected to the introduction path 117 relative to the ejection portion 114.

[0239] The jet liquid flow path 130 may also be a path for circulating the jet liquid. In one example, the jet liquid flow path 130 has a first connecting path 131 and a second connecting path 132. The first connecting path 131 is connected to the first jet liquid storage portion 123 and the second jet liquid storage portion 124. The jet portion 114 is located in the first connecting path 131. That is, the first connecting path 131 is connected to the jet portion 114. The second connecting path 132 is connected to the first jet liquid storage portion 123 and the second jet liquid storage portion 124. The jet liquid can circulate through the first connecting path 131 and the second connecting path 132. In one example, the jet liquid flows from the second jet liquid storage portion 124 to the first jet liquid storage portion 123 through the first connecting path 131. The jet liquid flows from the first jet liquid storage portion 123 to the second jet liquid storage portion 124 through the second connecting path 132.

[0240] The ejection mechanism 113 includes an ejection liquid supply valve 133. The ejection liquid supply valve 133 is located in the ejection liquid flow path 128. Specifically, the ejection liquid supply valve 133 is located in the ejection liquid supply flow path 129. When the ejection liquid supply valve 133 is opened, the ejection liquid can be supplied from the supply source 112 to the first ejection liquid storage portion 123. Normally, the ejection liquid supply valve 133 is closed. When it is necessary to supply the ejection liquid to the ejection liquid storage portion, the ejection liquid supply valve 133 is opened.

[0241] The ejection mechanism 113 has one or more ejection liquid amount detection units. The ejection liquid amount detection units are configured to detect the amount of ejection liquid stored in the ejection liquid storage unit. In one example, the ejection mechanism 113 has a first ejection liquid amount detection unit 134. The first ejection liquid amount detection unit 134 is mounted on the first ejection liquid storage unit 123. The first ejection liquid amount detection unit 134 detects the amount of ejection liquid stored in the first ejection liquid storage unit 123. The ejection mechanism 113 may also have a second ejection liquid amount detection unit. The second ejection liquid amount detection unit detects the amount of ejection liquid stored in the second ejection liquid storage unit 124.

[0242] The ejection liquid amount detection unit may detect the ejection liquid amount based on the conduction between electrodes, or may detect the ejection liquid amount based on the reflected light of the prism. The ejection liquid amount detection unit may also detect the liquid amount based on the vibration waveform of the ejection liquid of the piezoelectric sensor. The ejection liquid amount detection unit may also detect the liquid amount based on the pressure of the ejection liquid detected by the pressure sensor. The ejection liquid amount detection unit detects the ejection liquid amount, thereby controlling the ejection liquid amount stored in the ejection liquid storage unit.

[0243] The ejection mechanism 113 has a pressure regulating mechanism 135. The pressure regulating mechanism 135 is a mechanism for regulating the pressure in the ejection liquid storage section. The pressure regulating mechanism 135 can also regulate the pressure in the moisturizing liquid storage section described later. The pressure regulating mechanism 135 causes the ejection liquid to flow by regulating the pressure in the ejection liquid storage section. The pressure regulating mechanism 135 regulates the pressure in the first ejection liquid storage section 123. The pressure regulating mechanism 135 regulates the pressure in the second ejection liquid storage section 124.

[0244] The pressure regulating mechanism 135 is connected to the discharge liquid storage portion. The pressure regulating mechanism 135 is connected to the first discharge liquid storage portion 123. The pressure regulating mechanism 135 is connected to the second discharge liquid storage portion 124. The pressure regulating mechanism 135 is in communication with the first discharge liquid chamber 125. The pressure regulating mechanism 135 is in communication with the second discharge liquid chamber 126.

[0245] The pressure adjustment mechanism 135 generates a pressure difference between the first ejection liquid reservoir 123 and the second ejection liquid reservoir 124. As a result, the ejection liquid flows between the first ejection liquid reservoir 123 and the second ejection liquid reservoir 124. In one example, the ejection liquid flows from the second ejection liquid reservoir 124 to the first ejection liquid reservoir 123 through the first connecting flow path 131. As a result, the liquid circulates in the first ejection liquid reservoir 123 and the second ejection liquid reservoir 124.

[0246] The pressure regulating mechanism 135 includes a regulating part. The regulating part is connected to the ejection liquid storage part. In one example, the pressure regulating mechanism 135 includes a first regulating part 136 and a second regulating part 137. The first regulating part 136 is connected to the first ejection liquid storage part 123. The second regulating part 137 is connected to the second ejection liquid storage part 124.

[0247] The adjusting unit adjusts the pressure in the spray liquid storage unit. The adjusting unit may also adjust the pressure in the spray liquid storage unit by pressurizing or depressurizing the spray liquid storage unit. The adjusting unit is, for example, connected to the upper portion of the spray liquid chamber. That is, the adjusting unit is connected to the air stored in the spray liquid storage unit. The adjusting unit adjusts the pressure in the spray liquid storage unit by sending air into the spray liquid storage unit or sucking air from the spray liquid storage unit. The adjusting unit causes the spray liquid to flow by adjusting the pressure in the spray liquid storage unit. The first adjusting unit 136 adjusts the pressure in the first spray liquid storage unit 123. The first adjusting unit 136 is connected to the upper portion of the first spray liquid chamber 125. The second adjusting unit 137 adjusts the pressure in the second spray liquid storage unit 124. The second adjusting unit 137 is connected to the upper portion of the second spray liquid chamber 126.

[0248] The first adjustment part 136 and the second adjustment part 137 adjust the pressure in the first ejection liquid storage part 123 and the pressure in the second ejection liquid storage part 124 so that a pressure difference is generated in the first ejection liquid storage part 123 and the second ejection liquid storage part 124. In detail, the first adjustment part 136 and the second adjustment part 137 adjust the pressure in the first ejection liquid storage part 123 and the pressure in the second ejection liquid storage part 124, respectively, so that the pressure in the first ejection liquid storage part 123 is lower than the pressure in the second ejection liquid storage part 124. Thus, the ejection liquid flows from the second ejection liquid storage part 124 to the first ejection liquid storage part 123 through the first connecting flow path 131. That is, the ejection liquid flows in the ejection part 114 from the introduction path 117 toward the derivation path 121.

[0249] The first adjustment unit 136 varies the pressure in the first ejection liquid storage unit 123 so that the ejection unit 114 is always maintained at a predetermined negative pressure. The second adjustment unit 137 varies the pressure in the second ejection liquid storage unit 124 so that the ejection unit 114 is always maintained at a predetermined negative pressure. Thus, the ejection unit 114 can appropriately eject the ejection liquid while allowing the ejection liquid to flow from the second ejection liquid storage unit 124 to the first ejection liquid storage unit 123.

[0250] The adjustment section includes an adjustment pump. The adjustment pump is connected to the ejection liquid storage section. The adjustment pump is a pump that adjusts the pressure in the ejection liquid storage section. The adjustment pump is, for example, a diaphragm pump. The first adjustment section 136 includes a first adjustment pump 138. The first adjustment pump 138 is, for example, a pressure reducing pump. The first adjustment pump 138 is connected to the first ejection liquid storage section 123. The first adjustment pump 138 reduces the pressure in the first ejection liquid storage section 123. In detail, the first adjustment pump 138 reduces the pressure in the first ejection liquid storage section 123 by introducing air from the first ejection liquid storage section 123. The second adjustment section 137 includes a second adjustment pump 139. The second adjustment pump 139 is, for example, a pressure increasing pump. The second adjustment pump 139 is connected to the second ejection liquid storage section 124. The second adjustment pump 139 increases the pressure in the second ejection liquid storage section 124. Specifically, the second adjustment pump 139 pressurizes the second ejection liquid storage portion 124 by sending air into the second ejection liquid storage portion 124 .

[0251] The first adjustment pump 138 is driven to allow the ejection liquid to flow into the first ejection liquid storage portion 123. When the first adjustment pump 138 depressurizes the first ejection liquid storage portion 123, the ejection liquid flows into the first ejection liquid storage portion 123. For example, when the first adjustment pump 138 depressurizes the first ejection liquid storage portion 123, the ejection liquid can flow from the supply source 112 into the first ejection liquid storage portion 123. When the first adjustment pump 138 depressurizes the first ejection liquid storage portion 123, the ejection liquid flows from the ejection portion 114 into the first ejection liquid storage portion 123 through the first connecting flow path 131.

[0252] The second adjustment pump 139 is driven to cause the ejection liquid to flow out from the second ejection liquid storage portion 124. When the second adjustment pump 139 pressurizes the second ejection liquid storage portion 124, the ejection liquid flows out from the second ejection liquid storage portion 124. For example, when the second adjustment pump 139 pressurizes the second ejection liquid storage portion 124, the ejection liquid flows out from the second ejection liquid storage portion 124 toward the ejection portion 114 through the first connecting flow path 131.

[0253] The second adjustment pump 139 is not limited to a pressurizing pump, and may be a decompression pump like the first adjustment pump 138, or may be a pump capable of pressurizing and decompressing the second ejection liquid storage portion 124. In this case, the second adjustment pump 139 decompresses the second ejection liquid storage portion 124 so that the pressure in the second ejection liquid storage portion 124 is greater than the pressure in the first ejection liquid storage portion 123. In this case, since a pressure difference is generated between the first ejection liquid storage portion 123 and the second ejection liquid storage portion 124, the ejection liquid also flows from the second ejection liquid storage portion 124 to the first ejection liquid storage portion 123 through the first connecting flow path 131. In addition, by decompressing the second ejection liquid storage portion 124 by the second adjustment pump 139, the ejection liquid can flow back from the ejection portion 114 to the second ejection liquid storage portion 124. In this case, the bubbles captured and collected by the filter 120 are allowed to flow to the second ejection liquid storage portion 124 , so that the bubbles can be removed from the filter 120 .

[0254] The adjustment section has a pressure sensor. The pressure sensor is connected to the ejection liquid storage section. The pressure sensor detects the pressure in the ejection liquid storage section. The first adjustment section 136 has a first pressure sensor 140. The first pressure sensor 140 is connected to the first ejection liquid storage section 123. The first pressure sensor 140 detects the pressure in the first ejection liquid storage section 123. The second adjustment section 137 has a second pressure sensor 141. The second pressure sensor 141 is connected to the second ejection liquid storage section 124. The second pressure sensor 141 detects the pressure in the second ejection liquid storage section 124. In the adjustment section, the adjustment pump is driven based on the detection result of the pressure sensor. As a result, the ejection section 114 is maintained at a predetermined negative pressure.

[0255] The adjustment section has an atmospheric opening valve. The atmospheric opening valve is connected to the ejection liquid storage section. The atmospheric opening valve is a valve that opens the inside of the ejection liquid storage section to the atmosphere. The first adjustment section 136 has a first atmospheric opening valve 142. The first atmospheric opening valve 142 is connected to the first ejection liquid storage section 123. The first atmospheric opening valve 142 opens the inside of the first ejection liquid storage section 123 to the atmosphere. The second adjustment section 137 has a second atmospheric opening valve 143. The second atmospheric opening valve 143 is connected to the second ejection liquid storage section 124. The second atmospheric opening valve 143 opens the inside of the second ejection liquid storage section 124 to the atmosphere. In order to suppress the evaporation of the ejection liquid in the ejection liquid storage section, the atmospheric opening valve includes a capillary that connects the inside of the ejection liquid storage section to the atmosphere. Since the flow path resistance of the capillary is large, the ejection liquid is difficult to evaporate.

[0256] The pressure regulating mechanism 135 includes a liquid feeding pump 144 for flowing the ejection liquid. The liquid feeding pump 144 is located in the ejection liquid flow path 130. Specifically, the liquid feeding pump 144 is located in the second connecting flow path 132. The liquid feeding pump 144 delivers the ejection liquid from the first ejection liquid storage portion 123 to the second ejection liquid storage portion 124 through the second connecting flow path 132. Therefore, in one example, the ejection liquid circulates through the first adjustment pump 138, the second adjustment pump 139, and the liquid feeding pump 144.

[0257] The liquid ejection device 111 has a moisturizing mechanism 150. The moisturizing mechanism 150 is a mechanism for moisturizing the ejection liquid flowing through the ejection mechanism 113. The moisturizing mechanism 150 moisturizes the ejection liquid with the moisturizing liquid. In detail, the moisturizing mechanism 150 moisturizes the ejection liquid by supplying the water contained in the moisturizing liquid to the ejection liquid. The moisturizing liquid is a liquid for moisturizing the ejection liquid. The moisturizing liquid is, for example, a glycerin aqueous solution.

[0258] The moisturizing mechanism 150 has one or more moisturizing liquid storage parts. The moisturizing liquid storage parts are configured to store moisturizing liquid. The moisturizing liquid storage parts define a moisturizing liquid chamber. The moisturizing liquid chamber is a space for storing moisturizing liquid. In one example, the moisturizing mechanism 150 has a first moisturizing liquid storage part 151. The first moisturizing liquid storage part 151 defines a first moisturizing liquid chamber 152. In one example, the moisturizing liquid storage part stores air together with the moisturizing liquid. Therefore, there is a liquid surface of the moisturizing liquid in the moisturizing liquid storage part. The moisturizing liquid storage part can also be filled with the moisturizing liquid.

[0259] The moisturizing mechanism 150 has one or more moisturizing parts. In one example, the moisturizing mechanism 150 has a first moisturizing part 153. The moisturizing part is adjacent to the ejection mechanism 113. In one example, the first moisturizing part 153 is adjacent to the ejection liquid storage part. In detail, the first moisturizing part 153 is adjacent to the first ejection liquid storage part 123. The moisturizing part is adjacent to the moisturizing liquid storage part. In detail, the first moisturizing part 153 is adjacent to the first moisturizing liquid storage part 151. The first moisturizing part 153 moisturizes the ejection liquid stored in the first ejection liquid storage part 123 by the moisturizing liquid stored in the first moisturizing liquid storage part 151. The moisturizing part is not limited to being adjacent to the moisturizing liquid storage part, and may also be adjacent to the stirring part 155 described later.

[0260] The moisturizing section has one or more moisture permeable membranes. The moisture permeable membranes are located at a position that separates the ejection liquid from the moisturizing liquid. In detail, the moisture permeable membrane is located at a position that separates the ejection liquid flowing through the ejection mechanism 113 from the moisturizing liquid flowing through the moisturizing mechanism 150. In one example, the first moisturizing section 153 has a first moisture permeable membrane 154. The first moisture permeable membrane 154 is located at a position that separates the ejection liquid stored in the first ejection liquid storage section 123 from the moisturizing liquid stored in the first moisturizing liquid storage section 151. The first moisture permeable membrane 154 is located at a position that constitutes a wall of the first ejection liquid storage section 123. The first moisture permeable membrane 154 is located at a position that constitutes a wall of the first moisturizing liquid storage section 151. The first moisture permeable membrane 154 separates the first ejection liquid chamber 125 from the first moisturizing liquid chamber 152.

[0261] A moisture permeable membrane is a membrane that allows gas to pass through but does not allow liquid to pass through. Therefore, the moisture permeable membrane separates the ejected liquid from the moisturizing liquid in a manner that prevents the ejected liquid and the moisturizing liquid from mixing. The moisture permeable membrane can be a porous membrane formed with a plurality of pores, or it can be a homogeneous membrane composed of a polymer material. The porous membrane defines a gap connected to a plurality of pores. The gap is the space within the moisture permeable membrane. In the pores, a curved liquid surface is generated due to the surface tension of the liquid. The curved liquid surface is the gas-liquid interface between the liquid stored in the liquid chamber and the gas located in the gap. Thus, the porous membrane allows gas to pass through but does not allow liquid to pass through. The homogeneous membrane is composed of, for example, silicon. The homogeneous membrane allows water vapor to pass through due to the dissolution and diffusion of water in the polymer, but does not allow liquid to pass through.

[0262] The first moisture permeable membrane 154 may also separate the first spraying liquid chamber 125 from the first moisturizing liquid chamber 152 in a state where the air stored in the first spraying liquid chamber 125 and the air stored in the first moisturizing liquid chamber 152 can enter and exit each other. In one example, the upper end of the first moisture permeable membrane 154 is located above the spraying liquid surface and the moisturizing liquid surface. That is, the first spraying liquid storage portion 123 stores the spraying liquid in a manner that the spraying liquid surface is located below the upper end of the first moisture permeable membrane 154. The first moisturizing liquid storage portion 151 stores the moisturizing liquid in a manner that the moisturizing liquid surface is located below the upper end of the first moisture permeable membrane 154. Thus, air can enter and exit the gap between the first spraying liquid chamber 125 and the first moisture permeable membrane 154. Air can enter and exit the gap between the first moisturizing liquid chamber 152 and the first moisture permeable membrane 154. For example, when the pressure adjustment mechanism 135 changes the pressure in the first spray liquid storage section 123 and the first moisturizing liquid storage section 151, air moves in the first spray liquid chamber 125 and the gap, so that it is difficult to generate a pressure difference between the first spray liquid chamber 125 and the gap. Similarly, by moving air in the first moisturizing liquid chamber 152 and the gap, it is difficult to generate a pressure difference between the first moisturizing liquid chamber 152 and the gap. As a result, the risk of the curved liquid surface formed in the pores of the first moisture permeable membrane 154 being destroyed due to the pressure difference, thereby reducing the risk of the spray liquid leaking into the first moisturizing liquid chamber 152 through the first moisture permeable membrane 154, or the moisturizing liquid leaking into the first spray liquid chamber 125 through the first moisture permeable membrane 154.

[0263] The first moisture permeable membrane 154 completely separates the first spray liquid chamber 125 from the first moisturizing liquid chamber 152. In one example, the upper end of the first moisture permeable membrane 154 is in contact with the first spray liquid reservoir 123 and the first moisturizing liquid reservoir 151. Thus, even if the spray liquid splashes or the moisturizing liquid splashes, the risk of mixing the spray liquid and the moisturizing liquid is reduced.

[0264] The first moisture permeable membrane 154 may not completely separate the first ejection liquid chamber 125 from the first moisturizing liquid chamber 152. For example, the upper end of the first moisture permeable membrane 154 may not be in contact with the first ejection liquid reservoir 123 and the first moisturizing liquid reservoir 151. In this case, the ejection liquid and the moisturizing liquid can be separated by locating the upper end of the first moisture permeable membrane 154 above the ejection liquid surface and the moisturizing liquid surface.

[0265] In the ejection liquid, water may evaporate over time. When water evaporates from the ejection liquid, the concentration of the ejection liquid increases. When the concentration of the ejection liquid increases, there is a risk that the ejection liquid increases in viscosity. When the ejection liquid increases in viscosity, the ejection unit 114 may not be able to eject the ejection liquid properly.

[0266] The moisturizing liquid moisturizes the ejecting liquid through the moisture permeable membrane. In detail, the moisturizing liquid moisturizes the ejecting liquid by supplying water to the ejecting liquid through the moisture permeable membrane. The water contained in the moisturizing liquid passes through the moisture permeable membrane as water vapor. Thus, the water is supplied to the ejecting liquid. In one example, the water of the moisturizing liquid stored in the first moisturizing liquid chamber 152 passes through the first moisture permeable membrane 154 and is supplied to the ejecting liquid stored in the first ejecting liquid chamber 125. The movement speed of the water supplied from the moisturizing liquid to the ejecting liquid is determined by the contact area between the ejecting liquid and the moisturizing liquid through the moisture permeable membrane. The larger the contact area between the ejecting liquid and the moisturizing liquid through the moisture permeable membrane, the greater the movement speed of the water. The movement speed of the water only needs to be greater than the evaporation speed of the ejecting liquid. In addition, the movement speed of the water supplied from the moisturizing liquid to the ejecting liquid is determined by the thickness of the moisture permeable membrane. The thinner the thickness of the moisture permeable membrane, the greater the movement speed of the water.

[0267] For the moisturizing liquid, an appropriate concentration is set in order to moisturize the ejected liquid. In detail, the concentration of the moisturizing liquid is set in such a way that the moisturizing power of the new ejected liquid is balanced with the moisturizing power of the moisturizing liquid. The moisturizing power is the ease of releasing moisture. That is, the greater the moisturizing power, the easier it is to supply moisture. Assuming that the moisturizing power of the moisturizing liquid stored in the moisturizing liquid chamber is smaller than the moisturizing power of the new ejected liquid, water moves from the ejected liquid to the moisturizing liquid. In this case, it is possible to promote an increase in the concentration of the ejected liquid. On the contrary, when the moisturizing power of the moisturizing liquid stored in the moisturizing liquid chamber is greater than the moisturizing power of the new ejected liquid, the concentration of the ejected liquid may drop too much. Therefore, in order to keep the ejected liquid at an appropriate concentration, the moisturizing liquid storage unit stores moisturizing liquid of an appropriate concentration when moisturizing the ejected liquid. Thus, when the moisturizing power of the ejected liquid decreases due to evaporation of water in the ejected liquid, water moves from the moisturizing liquid to the ejected liquid.

[0268] As water moves from the moisturizing liquid to the spray liquid, the amount of water in the moisturizing liquid decreases. In the moisturizing liquid, water evaporates over time, similarly to the spray liquid. Therefore, the concentration of the moisturizing liquid may increase. When the concentration of the moisturizing liquid increases, it may be impossible to moisturize the spray liquid.

[0269] The moisturizing mechanism 150 includes a stirring section 155. The stirring section 155 is configured to stir the moisturizing liquid. The concentration of the moisturizing liquid is made uniform by stirring the moisturizing liquid by the stirring section 155. Thus, even if the amount of water in the moisturizing liquid decreases locally, the risk of the concentration of the moisturizing liquid increasing is reduced.

[0270] The stirring part 155 is installed in the moisturizing liquid storage part. The stirring part 155 stirs the moisturizing liquid stored in the moisturizing liquid storage part. In one example, the stirring part 155 is installed in the first moisturizing liquid storage part 151. The stirring part 155 stirs the moisturizing liquid stored in the first moisturizing liquid storage part 151. That is, the stirring part 155 stirs the moisturizing liquid stored in the first moisturizing liquid chamber 152.

[0271] The stirring section 155 has a stirring passage 156. The stirring passage 156 has a first end 157 and a second end 158. The first end 157 and the second end 158 are connected to the first moisturizing liquid reservoir 151. That is, both ends of the stirring passage 156 are connected to the first moisturizing liquid reservoir 151.

[0272] The stirring section 155 has a stirring pump 159. The stirring pump 159 is located in the stirring flow path 156. The stirring pump 159 circulates the moisturizing liquid in the first moisturizing liquid storage section 151 through the stirring flow path 156. As a result, the moisturizing liquid stored in the first moisturizing liquid storage section 151 is stirred. In one example, when the stirring pump 159 is driven, the moisturizing liquid flows in the stirring flow path 156 from the first end 157 toward the second end 158.

[0273] The stirring section 155 is not limited to the one having the stirring flow path 156 and the stirring pump 159, but may also have a fin for stirring the moisturizing liquid in the first moisturizing liquid storage section 151. In this case, the moisturizing liquid in the first moisturizing liquid chamber 152 is stirred by driving the fin.

[0274] The moisturizing mechanism 150 includes a supply unit 160. The supply unit 160 is configured to supply water to the moisturizing liquid stored in the moisturizing liquid storage unit. The supply unit 160 supplies water to the moisturizing liquid, thereby reducing the risk of the moisturizing liquid concentration increasing.

[0275] The supply unit 160 includes a water storage unit 161. The water storage unit 161 is configured to store water. Specifically, the water storage unit 161 stores water. The water storage unit 161 may store air together with water, similarly to the ejection liquid storage unit and the moisturizing liquid storage unit. The water storage unit 161 may store water in such a manner that the liquid level of the water is located above the moisturizing liquid level of the moisturizing liquid storage unit. The water storage unit 161 may be filled with water.

[0276] The supply section 160 has a moisture supply flow path 162. The moisture supply flow path 162 is connected to the moisture storage section 161. The moisture supply flow path 162 is connected to the moisturizing liquid storage section. Moisture is supplied from the moisture storage section 161 to the moisturizing liquid storage section through the moisture supply flow path 162. In one example, the moisture supply flow path 162 is connected to the moisture storage section 161 and the first moisturizing liquid storage section 151. Moisture is supplied from the moisture storage section 161 to the first moisturizing liquid storage section 151 through the moisture supply flow path 162. The moisture supply flow path 162 may also constitute a part of the stirring flow path 156. For example, the first end 157 may coincide with the end of the moisture supply flow path 162. The moisture supply flow path 162 may also be a flow path independent of the stirring flow path 156.

[0277] The supply unit 160 includes a water supply valve 163. The water supply valve 163 is located in the water supply flow path 162. When the water supply valve 163 is opened, water can be supplied from the water storage unit 161 to the first moisturizing liquid storage unit 151. Normally, the water supply valve 163 is closed. When it is necessary to supply water to the moisturizing liquid storage unit, the water supply valve 163 is opened.

[0278] The supply unit 160 may also include a decompression unit 164. The decompression unit 164 is configured to decompress the inside of the moisturizing liquid storage unit. The decompression unit 164 is connected to the moisturizing liquid storage unit. The decompression unit 164 is, for example, a decompression pump. In one example, the decompression unit 164 decompresses the inside of the first moisturizing liquid storage unit 151. As the inside of the first moisturizing liquid storage unit 151 is decompressed, water is supplied from the water storage unit 161 to the first moisturizing liquid storage unit 151.

[0279] The decompression unit 164 may be formed by the pressure adjustment mechanism 135. In one example, the decompression unit 164 is formed by the first adjustment unit 136. When the first adjustment unit 136 decompresses the first ejected liquid storage unit 123, the first moisturizing liquid storage unit 151 is also decompressed. Thus, water is supplied from the water storage unit 161 to the first moisturizing liquid storage unit 151. The decompression unit 164 may be provided independently of the first adjustment unit 136.

[0280] The supply unit 160 may also include a water pump 165. The water pump 165 is located in the water supply flow path 162. When the water pump 165 is driven in a state where the water supply valve 163 is opened, water is supplied from the water storage unit 161 to the first moisturizing liquid storage unit 151. The water pump 165 may be composed of the stirring pump 159 or a pump different from the stirring pump 159. In addition, the supply unit 160 may also supply water from the water storage unit 161 to the first moisturizing liquid storage unit 151 by the water head difference between the water storage unit 161 and the moisturizing liquid storage unit.

[0281] The moisturizing mechanism 150 has one or more moisturizing liquid amount detection units. The moisturizing liquid amount detection units are configured to detect the amount of moisturizing liquid stored in the moisturizing liquid storage unit. In one example, the moisturizing mechanism 150 has a first moisturizing liquid amount detection unit 166. The first moisturizing liquid amount detection unit 166 is mounted on the first moisturizing liquid storage unit 151. The first moisturizing liquid amount detection unit 166 detects the amount of moisturizing liquid stored in the first moisturizing liquid storage unit 151. The moisturizing mechanism 150 may also have a second moisturizing liquid amount detection unit.

[0282] The moisturizing liquid amount detection unit can detect the liquid amount based on the conduction between electrodes, or based on the reflected light of the prism, similarly to the ejection liquid amount detection unit. The moisturizing liquid amount detection unit can also detect the liquid amount based on the vibration waveform of the moisturizing liquid based on the piezoelectric sensor. The moisturizing liquid amount detection unit can also detect the liquid amount based on the pressure of the moisturizing liquid detected by the pressure sensor. The moisturizing liquid amount detection unit detects the liquid amount, thereby controlling the liquid amount of the moisturizing liquid storage unit. By controlling the liquid amount of the moisturizing liquid storage unit, the moisturizing liquid storage unit can store air together with the moisturizing liquid.

[0283] The moisturizing liquid amount detection unit detects the amount of moisturizing liquid, so that the concentration of the moisturizing liquid is appropriately maintained. That is, by controlling the amount of moisturizing liquid in the moisturizing liquid storage unit, the concentration of the moisturizing liquid is appropriately maintained. When water is supplied to the moisturizing liquid stored in the moisturizing liquid storage unit, the concentration of the moisturizing liquid decreases. That is, the amount of water supplied affects the moisturizing power of the moisturizing liquid. Therefore, by supplying water in a manner that makes the amount of moisturizing liquid stored in the moisturizing liquid storage unit constant, the moisturizing liquid stored in the moisturizing liquid storage unit is maintained at an appropriate concentration. In one example, water is supplied based on the detection result of the first moisturizing liquid amount detection unit 166 so that the amount of moisturizing liquid stored in the first moisturizing liquid storage unit 151 becomes constant, so that the moisturizing liquid stored in the first moisturizing liquid storage unit 151 is maintained at an appropriate concentration.

[0284] The liquid ejection device 111 includes a control unit 167. The control unit 167 controls various components of the liquid ejection device 111. The control unit 167 controls the ejection mechanism 113 and the moisturizing mechanism 150. For example, the control unit 167 controls the ejection unit 114, the ejection liquid supply valve 133, the pressure adjustment mechanism 135, the stirring unit 155, the water supply valve 163, the pressure reducing unit 164, and the water pump 165.

[0285] The control unit 167 may be composed of one or more processors that execute various processes according to a computer program. The control unit 167 may also be composed of one or more dedicated hardware circuits such as an ASIC that executes at least a portion of the various processes. The control unit 167 may be composed of a circuit including a combination of a processor and a hardware circuit. The processor includes a CPU and a memory such as a RAM and a ROM. The memory stores program codes or instructions configured to cause the CPU to execute a process. The memory, i.e., a computer-readable medium, includes any readable medium that can be accessed by a general-purpose or dedicated computer.

[0286] The control unit 167 drives the first adjustment pump 138 so that a predetermined negative pressure is maintained in the ejection unit 114. The control unit 167 drives the second adjustment pump 139 so that a predetermined negative pressure is maintained in the ejection unit 114. Furthermore, the control unit 167 drives the liquid delivery pump 144. Thus, the control unit 167 circulates the ejection liquid. The circulated ejection liquid is moisturized by the moisturizing liquid.

[0287] The control unit 167 may circulate the moisturizing liquid by driving the stirring unit 155. The control unit 167 drives the stirring pump 159 in a state where the water supply valve 163 is closed, thereby circulating the moisturizing liquid.

[0288] The control unit 167 can circulate the liquid all the time, or can circulate the liquid at a predetermined timing. That is, the control unit 167 can circulate the ejection liquid and the moisturizing liquid all the time, or can circulate the ejection liquid and the moisturizing liquid at a predetermined timing. The control unit 167 can also circulate the liquid during printing. The control unit 167 can also circulate the liquid during the maintenance of the liquid ejection device 111. The control unit 167 can also circulate the liquid when it is judged that the liquid needs to be circulated. The control unit 167 can also judge whether the liquid needs to be circulated based on the temperature and humidity during printing, the printing duty cycle, the elapsed time, etc. For example, the control unit 167 judges that the liquid needs to be circulated when the temperature and humidity are high. The control unit 167 judges that the liquid needs to be circulated when the printing duty cycle is small. The control unit 167 judges that the liquid needs to be circulated when the elapsed time is long. The elapsed time is the time that has passed since the last printing, the time that has passed since the last liquid supply, etc.

[0289] The control unit 167 controls the ejection liquid supply valve 133 based on the detection result of the first ejection liquid amount detection unit 134. When the ejection liquid amount detected by the first ejection liquid amount detection unit 134 is less than the threshold value, the control unit 167 opens the ejection liquid supply valve 133. As a result, the ejection liquid can be supplied from the supply source 112 to the first ejection liquid storage unit 123. At this time, the control unit 167 supplies the ejection liquid from the supply source 112 to the first ejection liquid storage unit 123 by causing the first adjustment unit 136 to reduce the pressure in the first ejection liquid storage unit 123. When the ejection liquid amount detected by the first ejection liquid amount detection unit 134 is greater than the threshold value, the control unit 167 closes the ejection liquid supply valve 133. As a result, the ejection liquid amount stored in the first ejection liquid storage unit 123 is maintained in a state greater than the threshold value.

[0290] The control unit 167 controls the water supply valve 163 based on the detection result of the first moisturizing liquid amount detection unit 166. When the amount of moisturizing liquid detected by the first moisturizing liquid amount detection unit 166 is less than the threshold value, the control unit 167 opens the water supply valve 163. As a result, water can be supplied from the water storage unit 161 to the first moisturizing liquid storage unit 151. At this time, the control unit 167 causes the decompression unit 164 to decompress the first moisturizing liquid storage unit 151, and water is supplied from the water storage unit 161 to the first moisturizing liquid storage unit 151. When the amount of moisturizing liquid detected by the first moisturizing liquid amount detection unit 166 is greater than the threshold value, the control unit 167 closes the water supply valve 163. As a result, the amount of moisturizing liquid stored in the first moisturizing liquid storage unit 151 is maintained in a state greater than the threshold value. Therefore, the moisturizing liquid is maintained at an appropriate concentration. The threshold value of the ejection liquid amount and the threshold value of the moisturizing liquid amount may also be different values.

[0291] The control unit 167 may also supply the spray liquid from the supply source 112 to the first spray liquid storage unit 123 by the water head difference between the supply source 112 and the first spray liquid storage unit 123. In this case, the spray liquid level stored in the supply source 112 is located above the spray liquid level stored in the first spray liquid storage unit 123. The control unit 167 opens the spray liquid supply valve 133 based on the detection result of the first spray liquid amount detection unit 134, thereby supplying the spray liquid to the first spray liquid storage unit 123.

[0292] The control unit 167 may also supply water from the water storage unit 161 to the first moisturizing liquid storage unit 151 by using the hydraulic head difference between the water storage unit 161 and the first moisturizing liquid storage unit 151. In this case, the liquid level of the water stored in the water storage unit 161 is located above the moisturizing liquid level stored in the first moisturizing liquid storage unit 151. Strictly speaking, since the density of water is different from that of the moisturizing liquid, in order to make the water flow from the water storage unit 161 to the first moisturizing liquid storage unit 151, it is sufficient that there is a hydraulic head difference between the two. The control unit 167 opens the water supply valve 163 based on the detection result of the first moisturizing liquid amount detection unit 166, thereby supplying water to the first moisturizing liquid storage unit 151.

[0293] The controller 167 may supply water from the water storage part 161 to the first moisturizing liquid storage part 151 by driving the water pump 165. The controller 167 drives the water pump 165 with the water supply valve 163 open to supply water from the water storage part 161 to the first moisturizing liquid storage part 151.

[0294] Function and effect

[0295] Next, the functions and effects of the above-described embodiment will be described.

[0296] (1) The moisturizing mechanism 150 includes: a first moisturizing liquid storage portion 151 for storing the moisturizing liquid; a first moisturizing portion 153 adjacent to the ejection mechanism 113; and a stirring portion 155 for stirring the moisturizing liquid stored in the first moisturizing liquid storage portion 151. The first moisturizing portion 153 includes a first moisture permeable membrane 154 for separating the ejection liquid from the moisturizing liquid. According to the above structure, the concentration of the moisturizing liquid is uniformized by stirring the moisturizing liquid by the stirring portion 155. Therefore, the concentration of the moisturizing liquid is unlikely to decrease. As a result, the ejection liquid is appropriately moisturized.

[0297] (2) The stirring section 155 includes a stirring passage 156 for circulating the moisturizing liquid, and a stirring pump 159 located in the stirring passage 156. The stirring passage 156 includes a first end 157 connected to the first moisturizing liquid storage section 151, and a second end 158 connected to the first moisturizing liquid storage section 151. According to the above structure, the moisturizing liquid stored in the first moisturizing liquid storage section 151 circulates in the stirring passage 156 by driving the stirring pump 159. As a result, the concentration of the moisturizing liquid is made uniform.

[0298] (3) The supply unit 160 includes a water storage unit 161 for storing water, and a water supply flow path 162 connected to the water storage unit 161 and the first moisturizing liquid storage unit 151. According to the above structure, water is supplied from the water storage unit 161 to the first moisturizing liquid storage unit 151 through the water supply flow path 162. This reduces the risk of the concentration of the moisturizing liquid increasing.

[0299] (4) The supply unit 160 includes the water pump 165 located in the water supply flow path 162. According to the above configuration, water is supplied from the water storage unit 161 to the first moisturizing liquid storage unit 151 by driving the water pump 165. This reduces the risk of the moisturizing liquid concentration increasing.

[0300] (5) The water storage portion 161 stores water so that the liquid level of the water is located above the liquid level of the moisturizing liquid stored in the first moisturizing liquid storage portion 151. According to the above structure, water is supplied from the water storage portion 161 to the first moisturizing liquid storage portion 151 due to the hydraulic head difference between the water storage portion 161 and the first moisturizing liquid storage portion 151. Thus, the risk of the moisturizing liquid concentration increasing is reduced.

[0301] (6) The supply unit 160 includes the decompression unit 164 for decompressing the first moisturizing liquid storage unit 151. According to the above configuration, the decompression unit 164 decompresses the first moisturizing liquid storage unit 151, so that water is supplied from the water storage unit 161 to the first moisturizing liquid storage unit 151. This reduces the risk of the moisturizing liquid concentration increasing.

[0302] (7) The control unit 167 opens the water supply valve 163 when the amount of the moisturizing liquid detected by the first moisturizing liquid amount detection unit 166 is less than the threshold value, and closes the water supply valve 163 when the amount of the moisturizing liquid detected by the first moisturizing liquid amount detection unit 166 is greater than the threshold value. When water is supplied from the moisturizing liquid to the ejected liquid, the amount of water in the moisturizing liquid decreases. Therefore, the amount of the moisturizing liquid stored in the first moisturizing liquid storage unit 151 decreases. According to the above structure, water is supplied from the water storage unit 161 to the first moisturizing liquid storage unit 151 based on the amount of the moisturizing liquid stored in the first moisturizing liquid storage unit 151, so that the concentration of the moisturizing liquid can be appropriately maintained.

[0303] (8) The first moisturizing portion 153 is adjacent to the first spray liquid storage portion 123 and the first moisturizing liquid storage portion 151. The first moisture permeable membrane 154 separates the spray liquid stored in the first spray liquid storage portion 123 from the moisturizing liquid stored in the first moisturizing liquid storage portion 151. According to the above structure, the spray liquid stored in the first spray liquid storage portion 123 is moisturized. Thus, the first spray liquid storage portion 123 can store the moisturized spray liquid.

[0304] Seventeenth Embodiment

[0305] Next, a seventeenth embodiment of the liquid ejection device 111 will be described. The seventeenth embodiment is different from the sixteenth embodiment in that the position of the adjustment pump is different. In the seventeenth embodiment, the differences from the sixteenth embodiment will be mainly described.

[0306] like Fig.18 As shown, the first adjustment pump 138 and the second adjustment pump 139 are located in the first connecting flow path 131. Specifically, the first adjustment pump 138 is located between the ejection portion 114 and the first ejection liquid storage portion 123 in the first connecting flow path 131. The second adjustment pump 139 is located between the ejection portion 114 and the second ejection liquid storage portion 124 in the first connecting flow path 131.

[0307] When the first adjustment pump 138 is driven, the ejection liquid flows from the ejection portion 114 to the first ejection liquid storage portion 123. When the second adjustment pump 139 is driven, the ejection liquid flows from the second ejection liquid storage portion 124 to the ejection portion 114. When the liquid delivery pump 144 is driven, the ejection liquid flows from the first ejection liquid storage portion 123 to the second ejection liquid storage portion 124. In this way, the ejection liquid circulates through the first adjustment pump 138, the second adjustment pump 139, and the liquid delivery pump 144. In this example, by driving the liquid delivery pump 144, the inside of the first ejection liquid storage portion 123 can be set to a negative pressure. By setting the inside of the first ejection liquid storage portion 123 to a negative pressure by the liquid delivery pump 144, the ejection liquid is supplied from the supply source 112 to the first ejection liquid storage portion 123. Furthermore, the liquid feeding pump 144 sets the pressure in the first moisturizing liquid storage section 151 to be negative through the first ejected liquid storage section 123 , so that water is supplied from the water storage section 161 to the first moisturizing liquid storage section 151 .

[0308] Eighteenth Embodiment

[0309] Next, an eighteenth embodiment of the liquid ejection device 111 will be described. The eighteenth embodiment is different from the sixteenth embodiment in the structure of the ejection mechanism 113. In the eighteenth embodiment, the differences from the sixteenth embodiment will be mainly described.

[0310] like Fig.19 As shown, the pressure regulating mechanism 135 replaces the regulating pump and generates a pressure difference between the first ejection liquid storage section 123 and the second ejection liquid storage section 124 by the water head difference. The pressure regulating mechanism 135 opens the first ejection liquid storage section 123 and the second ejection liquid storage section 124 to the atmosphere through the first atmosphere opening valve 142 and the second atmosphere opening valve 143, thereby generating a pressure difference between the first ejection liquid storage section 123 and the second ejection liquid storage section 124.

[0311] The first pressure sensor 140 and the second pressure sensor 141 are located in the first connecting flow path 131. Specifically, the first pressure sensor 140 is located between the ejection portion 114 and the first ejection liquid storage portion 123 in the first connecting flow path 131. The second pressure sensor 141 is located between the ejection portion 114 and the second ejection liquid storage portion 124 in the first connecting flow path 131.

[0312] The first ejection liquid storage portion 123 is located below the second ejection liquid storage portion 124. Specifically, the first ejection liquid storage portion 123 is arranged so that the ejection liquid level stored in the first ejection liquid storage portion 123 is located below the ejection liquid level stored in the second ejection liquid storage portion 124. Thus, the ejection liquid flows from the second ejection liquid storage portion 124 to the first ejection liquid storage portion 123.

[0313] The ejection portion 114 is located above the first ejection liquid reservoir 123 and below the second ejection liquid reservoir 124. Specifically, the ejection portion 114 is arranged so that the ejection liquid level stored in the first ejection liquid reservoir 123 is located above the nozzle surface 116. The ejection portion 114 is arranged so that the ejection liquid level stored in the second ejection liquid reservoir 124 is located above the nozzle surface 116.

[0314] When the liquid delivery pump 144 is driven, the spray liquid flows from the first spray liquid storage portion 123 to the second spray liquid storage portion 124. The liquid delivery pump 144 adjusts the water head difference between the first spray liquid storage portion 123 and the second spray liquid storage portion 124 based on the detection result of the first pressure sensor 140 and the detection result of the second pressure sensor 141. Thus, the spray liquid can circulate while maintaining the negative pressure in the spray portion 114.

[0315] The ejection mechanism 113 includes an ejection liquid pump 170. The ejection liquid pump 170 is located in the ejection liquid supply flow path 129. When the ejection liquid pump 170 is driven, the ejection liquid is supplied from the supply source 112 to the first ejection liquid storage portion 123. In the case where the ejection mechanism 113 does not include a structure for decompressing the first ejection liquid storage portion 123, the ejection liquid can be supplied from the supply source 112 to the first ejection liquid storage portion 123 by the ejection liquid pump 170. In the case where the ejection mechanism 113 includes a structure for decompressing the first ejection liquid storage portion 123, the ejection liquid pump 170 may be included.

[0316] The ejection mechanism 113 is not limited to the ejection liquid pump 170, and the ejection liquid may be supplied from the supply source 112 to the first ejection liquid storage portion 123 by the water head difference. The ejection mechanism 113 may also supply the ejection liquid from the supply source 112 to the first ejection liquid storage portion 123 by decompressing the first ejection liquid storage portion 123 through the first moisturizing liquid storage portion 151 via the decompression portion 164.

[0317] Nineteenth Embodiment

[0318] Next, a nineteenth embodiment of the liquid ejection device 111 will be described. The nineteenth embodiment is different from the sixteenth embodiment in the structure of the ejection mechanism 113. In the nineteenth embodiment, the differences from the sixteenth embodiment will be mainly described.

[0319] like Fig. 20As shown, the ejection mechanism 113 has a third ejection liquid storage portion 171. The third ejection liquid storage portion 171 stores ejection liquid. The third ejection liquid storage portion 171 defines a third ejection liquid chamber 172. The third ejection liquid storage portion 171 is connected to the first ejection liquid storage portion 123 and the second ejection liquid storage portion 124. In detail, the third ejection liquid storage portion 171 is located in the second connecting flow path 132. The third ejection liquid chamber 172 is connected to the first ejection liquid chamber 125 and the second ejection liquid chamber 126.

[0320] The first adjustment pump 138 is connected to the first ejection liquid storage portion 123 and the third ejection liquid storage portion 171. The first adjustment pump 138 depressurizes the first ejection liquid storage portion 123 and the third ejection liquid storage portion 171. The second adjustment pump 139 is connected to the second ejection liquid storage portion 124 and the third ejection liquid storage portion 171. The second adjustment pump 139 pressurizes the second ejection liquid storage portion 124 and the third ejection liquid storage portion 171.

[0321] The pressure regulating mechanism 135 has a switching valve. The switching valve is opened and closed. The pressure regulating mechanism 135 has a first switching valve 173 and a second switching valve 174. The first switching valve 173 is connected to the first adjusting pump 138 and the third ejection liquid storage portion 171. The first switching valve 173 is located between the first adjusting pump 138 and the third ejection liquid storage portion 171. When the first switching valve 173 is opened, the first adjusting pump 138 is connected to the third ejection liquid storage portion 171. The second switching valve 174 is connected to the second adjusting pump 139 and the third ejection liquid storage portion 171. The second switching valve 174 is located between the second adjusting pump 139 and the third ejection liquid storage portion 171. When the second switching valve 174 is opened, the second adjusting pump 139 is connected to the third ejection liquid storage portion 171.

[0322] The pressure regulating mechanism 135 is configured such that, when the first regulating pump 138 depressurizes the first ejection liquid reservoir 123 and the third ejection liquid reservoir 171, the pressure in the first ejection liquid reservoir 123 becomes greater than the pressure in the third ejection liquid reservoir 171. As a result, a pressure difference is generated between the first ejection liquid reservoir 123 and the third ejection liquid reservoir 171, and the ejection liquid flows from the first ejection liquid reservoir 123 to the third ejection liquid reservoir 171 through the second connecting flow path 132.

[0323] The pressure regulating mechanism 135 is configured such that, when the second regulating pump 139 pressurizes the inside of the second ejection liquid reservoir 124 and the inside of the third ejection liquid reservoir 171, the pressure inside the third ejection liquid reservoir 171 is higher than the pressure inside the second ejection liquid reservoir 124. As a result, a pressure difference is generated between the inside of the third ejection liquid reservoir 171 and the inside of the second ejection liquid reservoir 124, and thus the ejection liquid flows from the third ejection liquid reservoir 171 to the second ejection liquid reservoir 124 through the second connecting flow path 132.

[0324] The pressure adjustment mechanism 135 may also have a resistance portion. In detail, the pressure adjustment mechanism 135 has a first resistance portion 175 and a second resistance portion 176. The resistance portion is configured to become a resistance to the pressure change caused by the adjustment pump. The resistance portion is, for example, a capillary tube. The resistance portion is not limited to a capillary tube, and may be, for example, a valve. The resistance portion is located between the adjustment pump and the ejection liquid storage portion. The first resistance portion 175 is located between the first adjustment pump 138 and the first ejection liquid storage portion 123. That is, the first adjustment pump 138 depressurizes the first ejection liquid storage portion 123 through the first resistance portion 175. The second resistance portion 176 is located between the second adjustment pump 139 and the second ejection liquid storage portion 124. That is, the second adjustment pump 139 pressurizes the second ejection liquid storage portion 124 through the second resistance portion 176.

[0325] It is difficult for the first adjustment pump 138 to depressurize the first ejection liquid storage section 123 through the first resistance section 175. Therefore, when the first adjustment pump 138 is driven, a pressure difference is generated between the first ejection liquid storage section 123 and the third ejection liquid storage section 171. As a result, the ejection liquid flows from the first ejection liquid storage section 123 to the third ejection liquid storage section 171. In this example, the first adjustment section 136 has the first adjustment pump 138, the first switching valve 173, and the first resistance section 175. It is difficult for the second adjustment pump 139 to pressurize the second ejection liquid storage section 124 through the second resistance section 176. Therefore, when the second adjustment pump 139 is driven, a pressure difference is generated between the second ejection liquid storage section 124 and the third ejection liquid storage section 171. As a result, the ejection liquid flows from the third ejection liquid storage section 171 to the second ejection liquid storage section 124. In this example, the second adjustment unit 137 includes a second adjustment pump 139, a second switching valve 174, and a second resistance unit 176. Thus, the discharge liquid may flow from the first discharge liquid storage unit 123 toward the second discharge liquid storage unit 124 by the first adjustment pump 138 and the second adjustment pump 139 instead of the liquid delivery pump 144.

[0326] The ejection mechanism 113 may also have one or more one-way valves 177. The one-way valve 177 is a valve that allows liquid to flow in one direction and restricts liquid from flowing in the opposite direction. The ejection mechanism 113 has, for example, two one-way valves 177. The one-way valve 177 is located in the second connecting flow path 132. In detail, the two one-way valves 177 are respectively located between the first ejection liquid storage portion 123 and the third ejection liquid storage portion 171, and between the second ejection liquid storage portion 124 and the third ejection liquid storage portion 171 in the second connecting flow path 132. The one-way valve 177 reduces the risk of the ejection liquid flowing back through the second connecting flow path 132. That is, the one-way valve 177 reduces the risk of the ejection liquid flowing from the third ejection liquid storage portion 171 to the first ejection liquid storage portion 123, or the risk of the ejection liquid flowing from the second ejection liquid storage portion 124 to the third ejection liquid storage portion 171. Since the check valve 177 is located in the ejection liquid flow passage 130 , the flow of the ejection liquid circulating in the ejection liquid flow passage 130 is regulated.

[0327] The ejection mechanism 113 may also include a differential pressure valve. For example, the ejection mechanism 113 may also include a first differential pressure valve 178 and a second differential pressure valve 179. The first differential pressure valve 178 and the second differential pressure valve 179 are located in the first connecting flow path 131. In detail, the first differential pressure valve 178 is located between the second ejection liquid storage portion 124 and the ejection portion 114 in the first connecting flow path 131. The second differential pressure valve 179 is located between the ejection portion 114 and the first ejection liquid storage portion 123 in the first connecting flow path 131.

[0328] The differential pressure valve is configured to open and close by a pressure difference with the atmospheric pressure. The first differential pressure valve 178 opens when the pressure in the ejection portion 114 is lower than a predetermined value, for example, when the amount of ejected liquid in the ejection portion 114 decreases. The second differential pressure valve 179 opens when the pressure in the ejection portion 114 exceeds a predetermined value, for example, when the amount of ejected liquid in the ejection portion 114 increases. Thus, the ejection portion 114 is maintained at a negative pressure. Therefore, the differential pressure valve is useful when the pressure adjustment mechanism 135 does not have a pressure sensor.

[0329] The pressure in the ejection portion 114 when the first differential pressure valve 178 is opened may be different from the pressure in the ejection portion 114 when the second differential pressure valve 179 is opened. For example, the pressure in the ejection portion 114 when the first differential pressure valve 178 is opened may be greater than the pressure in the ejection portion 114 when the second differential pressure valve 179 is opened. Thus, the ejection liquid flows from the inlet path 117 toward the outlet path 121. That is, the ejection liquid can circulate while maintaining the inside of the ejection portion 114 at a negative pressure through the differential pressure valve.

[0330] Twentieth Embodiment

[0331] Next, a twentieth embodiment of the liquid ejection device 111 will be described. The twentieth embodiment is different from the sixteenth embodiment in the structure of the ejection mechanism 113. In the twentieth embodiment, the differences from the sixteenth embodiment will be mainly described.

[0332] like Fig.21 As shown, the ejection mechanism 113 has the first ejection liquid reservoir 123 and does not have the second ejection liquid reservoir 124. Both ends of the ejection liquid flow path 130 are connected to the first ejection liquid reservoir 123. The ejection liquid circulates in the ejection liquid flow path 130.

[0333] The first adjustment pump 138 and the second adjustment pump 139 are located in the ejection liquid flow path 130. Specifically, the first adjustment pump 138 and the second adjustment pump 139 are arranged in the ejection liquid flow path 130 so as to sandwich the ejection portion 114. That is, the ejection portion 114 is located between the first adjustment pump 138 and the second adjustment pump 139 in the ejection liquid flow path 130. In this example, the first adjustment pump 138 and the second adjustment pump 139 adjust the pressure of the first ejection liquid storage portion 123.

[0334] When the first adjustment pump 138 is driven, the discharge liquid flows from the discharge portion 114 to the first discharge liquid storage portion 123. When the second adjustment pump 139 is driven, the discharge liquid flows from the second discharge liquid storage portion 124 to the discharge portion 114. In this way, the discharge liquid circulates through the first adjustment pump 138 and the second adjustment pump 139.

[0335] Twenty-first embodiment

[0336] Next, a twenty-first embodiment of the liquid ejection device 111 will be described. The twenty-first embodiment is different from the sixteenth embodiment in the structure of the ejection mechanism 113. In the twenty-first embodiment, the differences from the sixteenth embodiment will be mainly described.

[0337] like Fig. 22 As shown, the ejection mechanism 113 has the first ejection liquid reservoir 123 and does not have the second ejection liquid reservoir 124. Both ends of the ejection liquid flow path 130 are connected to the ejection portion 114 and the first ejection liquid reservoir 123, respectively. Therefore, in this example, the ejection liquid does not circulate.

[0338] The liquid delivery pump 144 is located in the ejection liquid flow path 130. When the liquid delivery pump 144 is driven, the ejection liquid flows from the first ejection liquid storage portion 123 to the ejection portion 114. In this example, the liquid delivery pump 144 can supply the ejection liquid moisturized by the moisturizing liquid to the ejection portion 114.

[0339] Twenty-second embodiment

[0340] Next, a twenty-second embodiment of the liquid ejection device 111 will be described. The twenty-second embodiment is different from the sixteenth embodiment in the structure of the ejection mechanism 113. In the twenty-first embodiment, the differences from the sixteenth embodiment will be mainly described.

[0341] like Fig.23 As shown, the ejection mechanism 113 has the first ejection liquid reservoir 123 and does not have the second ejection liquid reservoir 124. Both ends of the ejection liquid flow path 130 are connected to the ejection portion 114 and the first ejection liquid reservoir 123, respectively. Therefore, in this example, the ejection liquid does not circulate.

[0342] The pressure regulating mechanism 135 has a first regulating pump 138 and does not have a second regulating pump 139. The first regulating pump 138 is connected to the first ejection liquid storage portion 123. The first regulating pump 138 pressurizes the first ejection liquid storage portion 123. When the first regulating pump 138 pressurizes the first ejection liquid storage portion 123, the ejection liquid is supplied from the first ejection liquid storage portion 123 to the ejection portion 114. The pressure regulating mechanism 135 is not limited to supplying the ejection liquid to the ejection portion 114 through the first regulating pump 138, and for example, the ejection liquid may be supplied to the ejection portion 114 through the head difference between the ejection portion 114 and the first ejection liquid storage portion 123. In this case, the ejection portion 114 is configured so that the nozzle surface 116 is located above the ejection liquid surface of the first ejection liquid storage portion 123.

[0343] The ejection mechanism 113 has a first differential pressure valve 178. The first differential pressure valve 178 is located in the ejection liquid flow path 130. When the pressure in the ejection portion 114 is lower than a predetermined value, the first differential pressure valve 178 opens. By opening the first differential pressure valve 178, the ejection liquid flows from the first ejection liquid storage portion 123 to the ejection portion 114. By the first differential pressure valve 178, a negative pressure is maintained in the ejection portion 114. The ejection mechanism 113 is not limited to maintaining a negative pressure in the ejection portion 114 by the first differential pressure valve 178, and for example, a negative pressure may be maintained in the ejection portion 114 by a head difference between the ejection portion 114 and the first ejection liquid storage portion 123. In this case, the ejection portion 114 is configured in such a way that the nozzle surface 116 is located above the ejection liquid surface of the first ejection liquid storage portion 123.

[0344] Twenty-third embodiment

[0345] Next, a twenty-third embodiment of the liquid ejection device 111 will be described. The twenty-third embodiment is different from the sixteenth embodiment in the structure of the ejection mechanism 113. In the twenty-third embodiment, the differences from the sixteenth embodiment will be mainly described.

[0346] like Fig.24As shown, the ejection mechanism 113 has a first differential pressure valve 178 and a second differential pressure valve 179 instead of the first pressure sensor 140 and the second pressure sensor 141. The first differential pressure valve 178 and the second differential pressure valve 179 are the same as those of the nineteenth embodiment. The first differential pressure valve 178 is located between the second ejection liquid storage portion 124 and the ejection portion 114 in the first connecting flow path 131. The second differential pressure valve 179 is located between the ejection portion 114 and the first ejection liquid storage portion 123 in the first connecting flow path 131. The ejection portion 114 is maintained at a negative pressure by the first differential pressure valve 178 and the second differential pressure valve 179. Therefore, the ejection liquid can circulate in a state where the ejection portion 114 is maintained at a negative pressure.

[0347] Twenty-fourth embodiment

[0348] Next, a twenty-fourth embodiment of the liquid ejection device 111 will be described. The twenty-fourth embodiment is different from the sixteenth embodiment in the structure of the ejection mechanism 113. In the twenty-fourth embodiment, the differences from the sixteenth embodiment will be mainly described.

[0349] like Fig.25 As shown, the ejection mechanism 113 has a first differential pressure valve 178 and a second differential pressure valve 179 instead of the first pressure sensor 140 and the second pressure sensor 141. The first differential pressure valve 178 and the second differential pressure valve 179 are the same as those of the nineteenth and twenty-third embodiments. The first differential pressure valve 178 is located between the second ejection liquid storage portion 124 and the ejection portion 114 in the first connecting flow path 131. The second differential pressure valve 179 is located between the ejection portion 114 and the first ejection liquid storage portion 123 in the first connecting flow path 131. The first differential pressure valve 178 and the second differential pressure valve 179 maintain the ejection portion 114 at a negative pressure.

[0350] The first adjustment pump 138 and the second adjustment pump 139 are located in the first connecting flow path 131 in the same manner as in the seventeenth embodiment. The first adjustment pump 138 is located between the ejection portion 114 and the first ejection liquid storage portion 123 in the first connecting flow path 131. Specifically, the first adjustment pump 138 is located between the second differential pressure valve 179 and the first ejection liquid storage portion 123 in the first connecting flow path 131. The second adjustment pump 139 is located between the ejection portion 114 and the second ejection liquid storage portion 124 in the first connecting flow path 131. Specifically, the second adjustment pump 139 is located between the first differential pressure valve 178 and the second ejection liquid storage portion 124 in the first connecting flow path 131.

[0351] When the first adjustment pump 138 is driven, the ejection liquid flows from the ejection portion 114 to the first ejection liquid storage portion 123. When the second adjustment pump 139 is driven, the ejection liquid flows from the second ejection liquid storage portion 124 to the ejection portion 114. When the liquid delivery pump 144 is driven, the ejection liquid flows from the first ejection liquid storage portion 123 to the second ejection liquid storage portion 124. In this way, the ejection liquid circulates through the first adjustment pump 138, the second adjustment pump 139, and the liquid delivery pump 144.

[0352] Twenty-fifth embodiment

[0353] Next, a twenty-fifth embodiment of the liquid ejection device 111 will be described. The twenty-fifth embodiment is different from the sixteenth embodiment in the structure of the ejection mechanism 113. In the twenty-fifth embodiment, the differences from the sixteenth embodiment will be mainly described.

[0354] like Fig.26 As shown, the pressure regulating mechanism 135 replaces the regulating pump and generates a pressure difference between the first ejection liquid storage part 123 and the second ejection liquid storage part 124 through the water head difference in the same way as the eighteenth embodiment. The pressure regulating mechanism 135 opens the first ejection liquid storage part 123 and the second ejection liquid storage part 124 to the atmosphere through the first atmosphere opening valve 142 and the second atmosphere opening valve 143, thereby generating a pressure difference in the first ejection liquid storage part 123 and the second ejection liquid storage part 124.

[0355] The ejection mechanism 113 includes a first differential pressure valve 178 and a second differential pressure valve 179. The first differential pressure valve 178 and the second differential pressure valve 179 are the same as those in the nineteenth embodiment, the twenty-third embodiment, and the twenty-fourth embodiment. The first differential pressure valve 178 is located between the second ejection liquid storage portion 124 and the ejection portion 114 in the first connecting flow path 131. The second differential pressure valve 179 is located between the ejection portion 114 and the first ejection liquid storage portion 123 in the first connecting flow path 131. The first differential pressure valve 178 and the second differential pressure valve 179 maintain the ejection portion 114 at a negative pressure.

[0356] The first ejection liquid storage portion 123 is located below the second ejection liquid storage portion 124. Specifically, the first ejection liquid storage portion 123 is arranged so that the ejection liquid level stored in the first ejection liquid storage portion 123 is located below the ejection liquid level stored in the second ejection liquid storage portion 124. Thus, the ejection liquid flows from the second ejection liquid storage portion 124 to the first ejection liquid storage portion 123.

[0357] The ejection portion 114 is located above the first ejection liquid reservoir 123 and below the second ejection liquid reservoir 124. Specifically, the ejection portion 114 is arranged so that the ejection liquid level stored in the first ejection liquid reservoir 123 is located above the nozzle surface 116. The ejection portion 114 is arranged so that the ejection liquid level stored in the second ejection liquid reservoir 124 is located above the nozzle surface 116.

[0358] Twenty-sixth embodiment

[0359] Next, a twenty-sixth embodiment of the liquid ejection device 111 will be described. The twenty-sixth embodiment is different from the sixteenth embodiment in the structure of the moisturizing mechanism 150. In the twenty-sixth embodiment, the differences from the sixteenth embodiment will be mainly described.

[0360] like Fig. 27 As shown, the first moisture permeable membrane 154 may also be located below the level of the ejected liquid of the first ejected liquid storage section 123. That is, the upper end of the first moisture permeable membrane 154 is located below the level of the ejected liquid of the first ejected liquid storage section 123. The first moisture permeable membrane 154 may also be located below the level of the moisturizing liquid of the first moisturizing liquid storage section 151. That is, the upper end of the first moisture permeable membrane 154 is located below the level of the moisturizing liquid of the first moisturizing liquid storage section 151. In this example, air cannot enter and exit the first ejected liquid storage section 123 and the first moisturizing liquid storage section 151 through the first moisture permeable membrane 154. In detail, air cannot enter and exit the gap between the first ejected liquid chamber 125 and the first moisture permeable membrane 154. Similarly, air cannot enter and exit the gap between the first moisturizing liquid chamber 152 and the first moisture permeable membrane 154. Therefore, a pressure difference may be generated between the first ejected liquid chamber 125 and the gap. In addition, a pressure difference may be generated between the first moisturizing liquid chamber 152 and the gap. For example, by reducing the pressure in the first spray liquid storage section 123 through the first adjustment pump 138, or by reducing the pressure in the first moisturizing liquid storage section 151 through the pressure reducing section 164, a pressure difference may be generated between the first spray liquid chamber 125 and the gap or between the first moisturizing liquid chamber 152 and the gap.

[0361] The first moisture permeable membrane 154 may be composed of a homogeneous membrane. When the first moisture permeable membrane 154 is composed of a homogeneous membrane, even if the first ejection liquid chamber 125 or the first moisturizing liquid chamber 152 is pressurized or depressurized, the liquid is difficult to seep out. Assuming that the first moisture permeable membrane 154 is composed of a porous membrane, when a pressure difference occurs between the first ejection liquid chamber 125 and the gap, and between the first moisturizing liquid chamber 152 and the gap, the curved liquid surface formed in the pores of the porous membrane may be destroyed. In this case, the liquid may seep out from the first moisture permeable membrane 154.

[0362] The moisturizing mechanism 150 includes a moisturizing liquid atmosphere opening valve 180. The moisturizing liquid atmosphere opening valve 180 is connected to the first moisturizing liquid storage portion 151. The moisturizing liquid atmosphere opening valve 180 opens the first moisturizing liquid chamber 152 to the atmosphere. In this example, since air cannot enter and exit the first spray liquid storage portion 123 and the first moisturizing liquid storage portion 151, the first moisturizing liquid storage portion 151 cannot be opened to the atmosphere through the first atmosphere opening valve 142. Therefore, the moisturizing mechanism 150 includes an atmosphere opening valve.

[0363] Twenty-seventh embodiment

[0364] Next, a twenty-seventh embodiment of the liquid ejection device 111 will be described. The twenty-seventh embodiment is different from the sixteenth embodiment in the configurations of the ejection mechanism 113 and the moisturizing mechanism 150. In the twenty-seventh embodiment, the differences from the sixteenth embodiment will be mainly described.

[0365] like Fig.28 As shown, the ejection mechanism 113 has a first differential pressure valve 178 and a second differential pressure valve 179, similarly to the twenty-fourth embodiment. The first adjustment pump 138 and the second adjustment pump 139, similarly to the twenty-fourth embodiment, are located in the first connecting flow path 131. Similar to the twenty-fourth embodiment, the ejection liquid circulates through the first adjustment pump 138, the second adjustment pump 139 and the liquid delivery pump 144.

[0366] The ejection liquid storage portion has a flexible membrane. In detail, the first ejection liquid storage portion 123 has a first flexible membrane 181. The second ejection liquid storage portion 124 has a second flexible membrane 182. The flexible membrane constitutes the wall of the ejection liquid storage portion. The flexible membrane is displaced according to the pressure in the ejection liquid storage portion. The volume of the ejection liquid storage portion changes due to the displacement of the flexible membrane. For example, the first flexible membrane 181 is displaced by the first adjustment pump 138, the liquid delivery pump 144, and the ejection liquid pump 170. The second flexible membrane 182 is displaced by the second adjustment pump 139 and the liquid delivery pump 144. In this example, the ejection liquid storage portion is filled with ejection liquid.

[0367] The moisturizing liquid storage portion has a flexible membrane similar to the ejection liquid storage portion. In detail, the first moisturizing liquid storage portion 151 has a third flexible membrane 183. The third flexible membrane 183 constitutes the wall of the first moisturizing liquid storage portion 151. The third flexible membrane 183 is displaced according to the pressure in the first moisturizing liquid storage portion 151. The volume of the first moisturizing liquid storage portion 151 changes due to the displacement of the third flexible membrane 183. For example, the third flexible membrane 183 is displaced by the stirring pump 159 and the water pump 165. In this example, the first moisturizing liquid storage portion 151 is filled with moisturizing liquid.

[0368] Twenty-eighth Embodiment

[0369] Next, a twenty-eighth embodiment of the liquid ejection device 111 will be described. The twenty-eighth embodiment is different from the sixteenth embodiment in the structure of the moisturizing mechanism 150. In the twenty-eighth embodiment, the differences from the sixteenth embodiment will be mainly described.

[0370] like Fig.29 As shown, the first moisturizing portion 153 has a plurality of first moisture permeable films 154. The plurality of first moisture permeable films 154 are respectively located at positions that separate the ejection liquid stored in the first ejection liquid storage portion 123 from the moisturizing liquid stored in the first moisturizing liquid storage portion 151. The plurality of first moisture permeable films 154, for example, separate the first ejection liquid chamber 125 and the first moisturizing liquid chamber 152 into a comb-tooth shape. Since the first moisturizing portion 153 has a plurality of first moisture permeable films 154, the contact area between the ejection liquid and the moisturizing liquid through the first moisture permeable films 154 becomes larger. As a result, the speed of water moving from the moisturizing liquid to the ejection liquid becomes larger. Therefore, the ejection liquid is easily moisturized by the moisturizing liquid.

[0371] Twenty-ninth embodiment

[0372] Next, a twenty-ninth embodiment of the liquid ejection device 111 will be described. The twenty-ninth embodiment is different from the sixteenth embodiment in the structure of the moisturizing mechanism 150. In the twenty-ninth embodiment, the differences from the sixteenth embodiment will be mainly described.

[0373] like Fig.30 As shown, the first moisturizing portion 153 is adjacent to the ejection liquid flow path 128. Specifically, the first moisturizing portion 153 is adjacent to the ejection liquid flow path 130. In one example, the first moisturizing portion 153 is adjacent to the second connection flow path 132. In addition, the first moisturizing portion 153 is adjacent to the stirring flow path 156. The first moisturizing portion 153 moisturizes the ejection liquid flowing through the second connection flow path 132 by the moisturizing liquid flowing through the stirring flow path 156.

[0374] The first moisture permeable membrane 154 is located at a position that separates the ejection liquid flowing through the second connecting flow path 132 from the moisturizing liquid flowing through the stirring flow path 156. The first moisture permeable membrane 154 is located at a position that constitutes a wall of the second connecting flow path 132. The first moisture permeable membrane 154 is located at a position that constitutes a wall of the stirring flow path 156. According to this example, the ejection liquid flowing through the ejection liquid flow path 130 is effectively moisturized by the moisturizing liquid circulating in the stirring flow path 156.

[0375] Thirtieth Embodiment

[0376] Next, a 30th embodiment of the liquid ejection device 111 will be described. The 30th embodiment is different from the 16th embodiment in the structure of the moisturizing mechanism 150. In the 30th embodiment, the differences from the 16th embodiment will be mainly described.

[0377] like Fig.31As shown, the first moisturizing portion 153 is adjacent to the ejection portion 114. The first moisturizing portion 153 may be located outside the ejection portion 114 or inside the ejection portion 114. In one example, the first moisturizing portion 153 is assembled to the ejection portion 114. The first moisturizing portion 153 is adjacent to the common liquid chamber 118, for example. The first moisturizing portion 153 may be adjacent to the inlet path 117, may be adjacent to the independent liquid chamber 119, and may be adjacent to the outlet path 121. In addition, the first moisturizing portion 153 is adjacent to the stirring flow path 156. In this example, the stirring flow path 156 extends inside the ejection portion 114. The first moisturizing portion 153 moisturizes the ejection liquid flowing through the ejection portion 114 by the moisturizing liquid flowing through the stirring flow path 156.

[0378] The first moisture permeable membrane 154 is located at a position to separate the ejection liquid flowing through the ejection portion 114 from the moisturizing liquid flowing through the stirring flow path 156. The first moisture permeable membrane 154 is located at a position constituting a wall defining the common liquid chamber 118. The first moisture permeable membrane 154 is located at a position constituting a wall constituting the stirring flow path 156. According to this example, the ejection liquid flowing through the ejection portion 114 is effectively moisturized by the moisturizing liquid circulating in the stirring flow path 156.

[0379] Thirty-first embodiment

[0380] Next, a thirty-first embodiment of the liquid ejection device 111 will be described. The thirty-first embodiment is different from the sixteenth embodiment in the structure of the moisturizing mechanism 150. In the thirty-first embodiment, the differences from the sixteenth embodiment will be mainly described.

[0381] like Fig.32 As shown, the first moisturizing section 153 is adjacent to the supply source 112. The first moisturizing section 153 is adjacent to the first moisturizing liquid storage section 151. The first moisturizing section 153 moisturizes the ejection liquid stored in the supply source 112 with the moisturizing liquid stored in the first moisturizing liquid storage section 151.

[0382] The first moisture permeable membrane 154 is located at a position that separates the ejected liquid stored in the supply source 112 from the moisturizing liquid stored in the first moisturizing liquid storage portion 151. The first moisture permeable membrane 154 is located at a position that constitutes a wall of the supply source 112. The first moisture permeable membrane 154 is located at a position that constitutes a wall of the first moisturizing liquid storage portion 151. According to this example, the ejected liquid stored in the supply source 112 is effectively moisturized.

[0383] Thirty-second embodiment

[0384] Next, a thirty-second embodiment of the liquid ejection device 111 will be described. The thirty-second embodiment differs from the sixteenth embodiment in the configurations of the ejection mechanism 113 and the moisturizing mechanism 150. In the thirty-second embodiment, the differences from the sixteenth embodiment will be mainly described.

[0385] like Fig.33 As shown, the discharge liquid flow path 128 directly connects the supply source 112 and the discharge portion 114. That is, in this example, the discharge mechanism 113 does not have a discharge liquid storage portion. The discharge liquid is directly supplied from the supply source 112 to the discharge portion 114 through the discharge liquid flow path 128.

[0386] The supply source 112 is integrally formed with the water storage portion 161. For example, the supply source 112 is formed of a cartridge that stores the ejection liquid and water. In this example, the water storage portion 161 is detachable from the liquid ejection device 111.

[0387] The ejection mechanism 113 may also include a first differential pressure valve 178. The first differential pressure valve 178 is the same as in other embodiments. The first differential pressure valve 178 is located in the ejection liquid flow path 128. The ejection portion 114 is maintained at a negative pressure by the first differential pressure valve 178. The ejection mechanism 113 may also maintain a negative pressure in the ejection portion 114 by a water head difference between the supply source 112 and the ejection portion 114, without being limited to the first differential pressure valve 178.

[0388] As in the 30th embodiment, the first moisturizing portion 153 is adjacent to the ejection portion 114. In one example, the first moisturizing portion 153 is adjacent to the common liquid chamber 118. In addition, the first moisturizing portion 153 is adjacent to the stirring flow path 156. In this example, the stirring flow path 156 extends in the ejection portion 114. The first moisturizing portion 153 moisturizes the ejection liquid flowing through the ejection portion 114 with the moisturizing liquid flowing through the stirring flow path 156.

[0389] The first moisture permeable membrane 154 is located at a position to separate the ejection liquid flowing through the ejection portion 114 from the moisturizing liquid flowing through the stirring flow path 156. The first moisture permeable membrane 154 is located at a position constituting a wall defining the common liquid chamber 118. The first moisture permeable membrane 154 is located at a position constituting a wall constituting the stirring flow path 156. According to this example, the ejection liquid flowing through the ejection portion 114 is effectively moisturized by the moisturizing liquid circulating in the stirring flow path 156.

[0390] Thirty-third embodiment

[0391] Next, a thirty-third embodiment of the liquid ejection device 111 will be described. The thirty-third embodiment is different from the sixteenth embodiment in the structure of the liquid ejection device 111. In the thirty-third embodiment, the differences from the sixteenth embodiment will be mainly described.

[0392] like Fig.34 As shown, the discharge liquid passage 128 directly connects the supply source 112 and the discharge portion 114 as in the thirty-second embodiment. That is, in this example, the discharge mechanism 113 does not have a discharge liquid storage portion. The discharge liquid is directly supplied from the supply source 112 to the discharge portion 114 through the discharge liquid passage 128.

[0393] The supply source 112 is integrally formed with the first moisturizing liquid storage portion 151 and the water storage portion 161. For example, the supply source 112 is formed by a box that stores the ejection liquid, moisturizing liquid, and water. In this example, the first moisturizing liquid storage portion 151 and the water storage portion 161 are detachable from the liquid ejection device 111.

[0394] The ejection mechanism 113 may also include a first differential pressure valve 178. The first differential pressure valve 178 is the same as in other embodiments. The first differential pressure valve 178 is located in the ejection liquid flow path 128. The ejection portion 114 is maintained at a negative pressure by the first differential pressure valve 178. The ejection mechanism 113 may also maintain a negative pressure in the ejection portion 114 by a water head difference between the supply source 112 and the ejection portion 114, without being limited to the first differential pressure valve 178.

[0395] The supply source 112 has a first moisturizing portion 153. The first moisturizing portion 153 is adjacent to the first moisturizing liquid storage portion 151. The first moisturizing portion 153 moisturizes the ejected liquid stored in the supply source 112 with the moisturizing liquid stored in the first moisturizing liquid storage portion 151. The first moisture permeable membrane 154 is located at a position that separates the ejected liquid stored in the supply source 112 from the moisturizing liquid stored in the first moisturizing liquid storage portion 151.

[0396] Thirty-fourth embodiment

[0397] Next, a thirty-fourth embodiment of the liquid ejection device 111 will be described. The thirty-fourth embodiment differs from the sixteenth embodiment in the structures of the ejection mechanism 113 and the moisturizing mechanism 150. In the thirty-fourth embodiment, the differences from the sixteenth embodiment will be mainly described.

[0398] like Fig.35 As shown, the moisturizing mechanism 150 has a second moisturizing liquid reservoir 185. The second moisturizing liquid reservoir 185 defines a second moisturizing liquid chamber 186. The second moisturizing liquid reservoir 185 stores, for example, air together with the moisturizing liquid. The second moisturizing liquid reservoir 185 may also be filled with the moisturizing liquid.

[0399] The moisturizing mechanism 150 includes a second moisturizing portion 187. The second moisturizing portion 187 is adjacent to the second spray liquid storage portion 124. The second moisturizing portion 187 is adjacent to the second moisturizing liquid storage portion 185. The second moisturizing portion 187 moisturizes the spray liquid stored in the second spray liquid storage portion 124 with the moisturizing liquid stored in the second moisturizing liquid storage portion 185.

[0400] The second moisturizing portion 187 has a second moisture permeable membrane 188. The second moisture permeable membrane 188 is located at a position to separate the ejection liquid from the moisturizing liquid. Specifically, the second moisture permeable membrane 188 is located at a position to separate the ejection liquid stored in the second ejection liquid storage portion 124 from the moisturizing liquid stored in the second moisturizing liquid storage portion 185. The second moisture permeable membrane 188 is located at a position constituting a wall of the second ejection liquid storage portion 124. The second moisture permeable membrane 188 is located at a position constituting a wall of the second moisturizing liquid storage portion 185. The second moisture permeable membrane 188 separates the second ejection liquid chamber 126 from the second moisturizing liquid chamber 186.

[0401] The second moisture permeable membrane 188 can also separate the second spraying liquid chamber 126 from the second moisturizing liquid chamber 186 in a state where the air stored in the second spraying liquid chamber 126 and the air stored in the second moisturizing liquid chamber 186 can enter and exit each other, similarly to the first moisture permeable membrane 154. In one example, the upper end of the second moisture permeable membrane 188 is located above the spraying liquid surface and the moisturizing liquid surface. That is, the second spraying liquid storage portion 124 stores the spraying liquid in a manner that the spraying liquid surface is located below the upper end of the second moisture permeable membrane 188. The second moisturizing liquid storage portion 185 stores the moisturizing liquid in a manner that the moisturizing liquid surface is located below the upper end of the second moisture permeable membrane 188. Thus, air can enter and exit the second spraying liquid chamber 126 and the second moisturizing liquid chamber 186 through the second moisture permeable membrane 188. In this case, it is difficult to generate a pressure difference in the second spraying liquid chamber 126 and the second moisturizing liquid chamber 186.

[0402] The second moisture permeable membrane 188 completely separates the second spray liquid chamber 126 from the second moisturizing liquid chamber 186. In one example, the upper end of the second moisture permeable membrane 188 is in contact with the second spray liquid reservoir 124 and the second moisturizing liquid reservoir 185. Thus, even if the spray liquid splashes or the moisturizing liquid splashes, the risk of mixing the spray liquid and the moisturizing liquid is reduced.

[0403] The second moisture permeable film 188 may not completely separate the second ejection liquid chamber 126 from the second moisturizing liquid chamber 186. For example, the upper end of the second moisture permeable film 188 may not be in contact with the second ejection liquid reservoir 124 and the second moisturizing liquid reservoir 185.

[0404] The stirring flow path 156 has a first circulation flow path 189 and a second circulation flow path 190. The first circulation flow path 189 is connected to the first moisturizing liquid storage part 151 and the second moisturizing liquid storage part 185. The first circulation flow path 189 is communicated with the first moisturizing liquid chamber 152 and the second moisturizing liquid chamber 186. In one example, the first circulation flow path 189 has a second end 158. The second circulation flow path 190 is connected to the first moisturizing liquid storage part 151 and the second moisturizing liquid storage part 185. The second circulation flow path 190 is communicated with the first moisturizing liquid chamber 152 and the second moisturizing liquid chamber 186. In one example, the second circulation flow path 190 has a first end 157.

[0405] The stirring pump 159 is located in the second circulation flow path 190. When the stirring pump 159 is driven, the moisturizing liquid flows from the first moisturizing liquid chamber 152 to the second moisturizing liquid chamber 186 through the second circulation flow path 190. At this time, the moisturizing liquid flows from the second moisturizing liquid chamber 186 to the first moisturizing liquid chamber 152 through the first circulation flow path 189. In this way, the moisturizing liquid circulates in the first moisturizing liquid storage section 151 and the second moisturizing liquid storage section 185. In this example, the spray liquid stored in the first spray liquid storage section 123 and the spray liquid stored in the second spray liquid storage section 124 are effectively moisturized.

[0406] The moisturizing liquid can be circulated by the first adjustment pump 138, the second adjustment pump 139, and the stirring pump 159. When the first adjustment pump 138 depressurizes the first spray liquid storage part 123, the first moisturizing liquid storage part 151 is also depressurized. When the second adjustment pump 139 pressurizes the second spray liquid storage part 124, the second moisturizing liquid storage part 185 is also pressurized. As a result, the moisturizing liquid flows from the second moisturizing liquid storage part 185 to the first moisturizing liquid storage part 151.

[0407] Thirty-fifth embodiment

[0408] Next, a thirty-fifth embodiment of the liquid ejection device 111 will be described. The thirty-fifth embodiment is different from the sixteenth embodiment in the structure of the ejection mechanism 113. In the thirty-fifth embodiment, the differences from the sixteenth embodiment will be mainly described.

[0409] like Fig.36 As shown, the ejection mechanism 113 may include a maintenance unit 191. The maintenance unit 191 is configured to perform maintenance on the ejection unit 114. Specifically, the maintenance unit 191 performs maintenance on the ejection unit 114 by moisturizing the ejection unit 114.

[0410] The maintenance unit 191 has a cover 192. The cover 192 forms a space communicating with the nozzle 115 by contacting the nozzle surface 116. This reduces the risk of water in the ejected liquid evaporating from the nozzle 115. The maintenance unit 191 maintains the ejection unit 114 by contacting the cover 192 with the nozzle surface 116. This is also called capping.

[0411] The cap 192 can also be flushed and cleaned to receive the spray liquid ejected from the ejection portion 114. Flushing is a maintenance to prevent the nozzle 115 from being clogged and to allow the spray liquid to be properly ejected from the nozzle 115. Cleaning is a maintenance to allow the spray liquid to be ejected from the nozzle 115 by applying pressure to the inside of the ejection portion 114.

[0412] The maintenance unit 191 includes an absorbent material 193. The absorbent material 193 is located in the cover 192. The absorbent material 193 absorbs the ejection liquid ejected from the ejection unit 114. When the cover 192 is closed in a state where the absorbent material 193 contains the ejection liquid, the ejection liquid in the nozzle 115 is effectively moisturized. That is, moisture moves from the ejection liquid contained in the absorbent material 193 to the ejection liquid located in the nozzle 115.

[0413] The first moisturizing section 153 is adjacent to the maintenance section 191. Specifically, the first moisturizing section 153 is adjacent to the absorbent material 193. The first moisturizing section 153 is adjacent to the stirring flow path 156. In this example, the stirring flow path 156 extends inside the cover 192. It can also be said that the cover 192 is located in the stirring flow path 156. Therefore, when the stirring pump 159 is driven, the moisturizing liquid circulates in the first moisturizing liquid storage section 151 and the cover 192 by flowing through the stirring flow path 156. The first moisturizing section 153 moisturizes the ejection liquid contained in the absorbent material 193 by the moisturizing liquid flowing through the stirring flow path 156.

[0414] The first moisture permeable membrane 154 is located at a position to separate the ejection liquid contained in the absorbent material 193 from the moisturizing liquid flowing through the stirring flow path 156. The first moisture permeable membrane 154 is mounted on the cover 192. The first moisture permeable membrane 154 is located in the cover 192. The first moisture permeable membrane 154 divides the inside of the cover 192 into an ejection liquid space 194 and a moisturizing liquid space 195. The ejection liquid space 194 is a space for holding the ejection liquid in the cover 192. The absorbent material 193 is located in the ejection liquid space 194. The moisturizing liquid space 195 is a space for storing the moisturizing liquid. The moisturizing liquid space 195 constitutes a part of the stirring flow path 156.

[0415] Moisture is supplied from the moisturizing liquid to the ejected liquid contained in the absorbent 193 through the first moisture-permeable film 154. Thus, the ejected liquid contained in the absorbent 193 is maintained at an ideal moisture content. Therefore, the moisturizing effect by the cap is improved.

[0416] Change Example

[0417] The above-mentioned embodiment can be implemented by being modified as follows. The above-mentioned embodiment and the following modified examples can be implemented by being combined with each other within the scope of no technical contradiction.

[0418] The discharge mechanism 113 may include a third discharge liquid amount detection unit that detects the discharge liquid amount in the third discharge liquid storage unit 171 .

[0419] The moisturizing mechanism 150 may include a second moisturizing liquid amount detecting unit that detects the amount of moisturizing liquid in the second moisturizing liquid storage unit 185 .

[0420] The moisturizing mechanism 150 may include a third moisturizing liquid storage unit. In addition, the moisturizing mechanism 150 may include a third moisturizing unit.

[0421] The liquid ejected by the ejection unit 114 is not limited to ink, and may be, for example, a liquid in which particles of a functional material are dispersed or mixed in a liquid. For example, the ejection unit 114 may eject a liquid containing, in a dispersed or dissolved form, materials such as electrode materials or colorants used in the manufacture of liquid crystal displays, electroluminescent displays, and surface-emitting displays.

[0422] Technical Thought

[0423] The technical ideas and effects learned from the above-described embodiments and modifications are described below.

[0424] (A) The liquid storage part includes: a storage body storing a spray liquid and a moisturizing liquid; and a moisture permeable membrane attached to the storage body, the moisture permeable membrane dividing the storage body into a spray liquid chamber and a moisturizing liquid chamber, the spray liquid chamber being a space for storing the spray liquid, the moisturizing liquid chamber being a space for storing the moisturizing liquid, and the storage body storing the spray liquid and the moisturizing liquid in such a manner that the liquid level of the spray liquid stored in the spray liquid chamber and the liquid level of the moisturizing liquid stored in the moisturizing liquid chamber are located below the upper end of the moisture permeable membrane. According to the above structure, the spray liquid and air are stored in the spray liquid chamber, and the moisturizing liquid and air are stored in the moisturizing liquid chamber. The air can move between the spray liquid chamber and the moisture permeable membrane. The air can move between the moisturizing liquid chamber and the moisture permeable membrane. Therefore, even if pressure is applied to the spray liquid, it is difficult to generate a pressure difference between the spray liquid chamber and the moisture permeable membrane. Even if pressure is applied to the moisturizing liquid, it is difficult to generate a pressure difference between the moisturizing liquid chamber and the moisture permeable membrane. Thereby, the risk of liquid seeping into the moisture-permeable membrane is reduced.

[0425] (B) The liquid storage part may be connected to a pressure changing mechanism that changes the pressure in the storage body, wherein the storage body is connected to the pressure changing mechanism in such a way that the upper part of the ejection liquid chamber or the upper part of the moisturizing liquid chamber communicates with the pressure changing mechanism. According to the above structure, even if the pressure changing mechanism changes the pressure of the ejection liquid chamber or the moisturizing liquid chamber, it is difficult to generate a pressure difference between the ejection liquid chamber or the moisturizing liquid chamber and the moisture permeable membrane. As a result, the risk of liquid seeping into the moisture permeable membrane is reduced.

[0426] (C) The liquid flow mechanism comprises: the above-mentioned liquid storage part; a pressure change mechanism connected to the storage body to change the pressure in the storage body; and a spray liquid flow path connected to the storage body and connected to the spray liquid chamber. The pressure in the storage body is changed by the pressure change mechanism, and the liquid in the spray liquid chamber flows in the spray liquid flow path. At this time, when a pressure difference is generated in the spray liquid chamber and the moisturizing liquid chamber, the liquid may seep into the breathable membrane. In this regard, according to the above-mentioned structure, the spray liquid and air are stored in the spray liquid chamber, and the moisturizing liquid and air are stored in the moisturizing liquid chamber. The air can move between the spray liquid chamber and the moisturizing liquid chamber. Therefore, even if the pressure change mechanism changes the pressure of the spray liquid chamber or changes the pressure of the moisturizing liquid chamber, it is difficult to generate a pressure difference between the spray liquid chamber or the moisturizing liquid chamber and the breathable membrane. As a result, the risk of liquid seeping into the breathable membrane is reduced.

[0427] (D) In ​​the above-mentioned liquid flow mechanism, the ejection liquid flow path may include: a first connection end connected to the storage body; and a second connection end connected to the storage body, and the first connection end and the second connection end are connected to the ejection liquid chamber. According to the above-mentioned structure, the pressure in the storage body is changed by the pressure changing mechanism, and the ejection liquid flows in the circulation flow path. As a result, the ejection liquid stored in the storage body circulates through the ejection liquid flow path. Through the circulation of the ejection liquid, water is supplied from the moisturizing liquid to the entire ejection liquid. Therefore, the moisturizing liquid can effectively moisturize the ejection liquid.

[0428] (E) The liquid ejection device comprises: the above-mentioned liquid flow mechanism; and an ejection part connected to the storage body, which ejects the ejection liquid stored in the ejection liquid chamber. The pressure in the storage body is changed by the pressure changing mechanism, and the liquid in the ejection liquid chamber flows in the ejection liquid flow path. At this time, when a pressure difference is generated in the ejection liquid chamber and the moisturizing liquid chamber, the liquid may seep into the breathable membrane. In this regard, according to the above-mentioned structure, the ejection liquid and air are stored in the ejection liquid chamber, and the moisturizing liquid and air are stored in the moisturizing liquid chamber. The air can move between the ejection liquid chamber and the moisturizing liquid chamber. Therefore, even if the pressure changing mechanism changes the pressure of the ejection liquid chamber or changes the pressure of the moisturizing liquid chamber, it is difficult to generate a pressure difference in the ejection liquid chamber or the moisturizing liquid chamber and the breathable membrane. Thereby, the risk of liquid seeping into the breathable membrane is reduced.

[0429] (F) In the above-mentioned liquid ejection device, the ejection liquid flow path may include: a first connection end connected to the storage body; and a second connection end connected to the storage body, the first connection end and the second connection end are connected to the ejection liquid chamber, and the ejection unit is located in the ejection liquid flow path. According to the above-mentioned structure, the pressure in the storage body is changed by the pressure changing mechanism, and the ejection liquid flows in the ejection liquid flow path. As a result, the ejection liquid stored in the storage body circulates through the ejection liquid flow path. Through the circulation of the ejection liquid, moisture is supplied from the moisturizing liquid to the entire ejection liquid. Therefore, the moisturizing liquid can effectively moisturize the ejection liquid. The ejection unit ejects the ejection liquid that has been effectively moisturized by the moisturizing liquid. Therefore, the ejection unit can appropriately eject the ejection liquid.

[0430] (G) In the above-mentioned liquid ejection device, the liquid storage part may be a first liquid storage part, the storage body may be a first storage body, the liquid flow mechanism may include a second liquid storage part, the second liquid storage part stores the ejection liquid, or stores the ejection liquid and the moisturizing liquid, the second liquid storage part includes a second storage body, the second storage body stores the ejection liquid, or stores the ejection liquid and the moisturizing liquid, the ejection liquid flow path may include: a first connecting flow path connected to the first storage body and the second storage body; and a second connecting flow path connected to the first storage body and the second storage body, the ejection part may be located in the first connecting flow path, and the pressure changing mechanism may include: a first changing part that changes the pressure in the first storage body; and a second changing part that changes the pressure in the second storage body. According to the above-mentioned structure, the pressure changing mechanism changes the pressure in the first storage body and the pressure in the second storage body, so that the ejection liquid circulates in the ejection liquid flow path. As a result, the moisturizing liquid can effectively moisturize the ejection liquid.

[0431] (H) In the above liquid ejection device, the liquid flow mechanism may include a stirring portion that stirs the moisturizing liquid stored in the moisturizing liquid chamber. According to the above configuration, the moisturizing liquid is stirred by the stirring portion, thereby reducing the risk of the moisturizing liquid concentration increasing.

[0432] (I) In the above-mentioned liquid ejection device, the stirring section may also include: a stirring flow path for circulating the moisturizing liquid stored in the moisturizing liquid chamber; and a stirring pump located in the stirring flow path, wherein the stirring flow path includes: a first end connected to the storage body; and a second end connected to the storage body, wherein the first end and the second end are connected to the moisturizing liquid chamber. According to the above-mentioned structure, the moisturizing liquid stored in the moisturizing liquid chamber circulates in the stirring flow path by being driven by the stirring pump. Thus, the moisturizing liquid stored in the moisturizing liquid chamber is stirred. Therefore, the risk of the concentration of the moisturizing liquid increasing is reduced.

[0433] (J) In the above-mentioned liquid ejection device, the moisture permeable membrane may be a first moisture permeable membrane, the ejection liquid chamber may be a first ejection liquid chamber, the moisturizing liquid chamber may be a first moisturizing liquid chamber, the second liquid storage portion may have a second moisture permeable membrane, the second moisture permeable membrane may be mounted on the second storage body, the second moisture permeable membrane may divide the second storage body into a second ejection liquid chamber and a second moisturizing liquid chamber, the second ejection liquid chamber may be a space for storing ejection liquid, the second moisturizing liquid chamber may be a space for storing moisturizing liquid, and the second storage body may store the moisturizing liquid in such a manner that the liquid level of the ejection liquid stored in the second ejection liquid chamber and the liquid level of the moisturizing liquid stored in the second moisturizing liquid chamber are located below the upper end of the second moisture permeable membrane. Spraying liquid and moisturizing liquid, the liquid flow mechanism has a stirring part, the stirring part stirs the moisturizing liquid stored in the first moisturizing liquid chamber and the moisturizing liquid stored in the second moisturizing liquid chamber, the stirring part has a stirring flow path, the stirring flow path circulates the moisturizing liquid in the first moisturizing liquid chamber and the second moisturizing liquid chamber, the stirring flow path has: a first circulation flow path connected to the first liquid storage part and the second liquid storage part; and a second circulation flow path connected to the first liquid storage part and the second liquid storage part, the first circulation flow path is connected to the first moisturizing liquid chamber and the second moisturizing liquid chamber, and the second circulation flow path is connected to the first moisturizing liquid chamber and the second moisturizing liquid chamber. According to the above structure, in the first liquid storage part and the second liquid storage part, the moisturizing liquid can moisturize the spraying liquid. As a result, the circulating spraying liquid is moisturized by the moisturizing liquid.

Claims

1. A liquid storage portion, characterized in that: have: Retention bodies, retention sprays and moisturizers; and A moisture permeable membrane is installed on the storage body. The moisture permeable membrane divides the storage body into a spray liquid chamber and a moisturizing liquid chamber. The spray liquid chamber is a space for storing the spray liquid. The moisturizing liquid chamber is a space for storing moisturizing liquid. The reservoir stores the ejection liquid and the moisturizing liquid such that the liquid level of the ejection liquid stored in the ejection liquid chamber and the liquid level of the moisturizing liquid stored in the moisturizing liquid chamber are located below the upper end of the moisture permeable membrane.

2. The liquid storage portion according to claim 1, characterized in that The liquid storage part is connected to a pressure changing mechanism, and the pressure changing mechanism changes the pressure in the storage body. The storage body is connected to the pressure changing mechanism in such a manner that an upper portion of the ejection liquid chamber or an upper portion of the moisturizing liquid chamber communicates with the pressure changing mechanism.

3. A liquid flow mechanism, characterized in that: have: The liquid storage portion according to claim 1; A pressure changing mechanism connected to the storage body to change the pressure in the storage body; and The ejection liquid flow path is connected to the storage body and communicates with the ejection liquid chamber.

4. The liquid flow mechanism according to claim 3, characterized in that: The ejection liquid flow path has: A first connecting end connected to the storage body; and The second connecting end is connected to the storage body, The first connection end and the second connection end are communicated with the ejection liquid chamber.

5. A liquid ejection device, characterized in that: have: The liquid flow mechanism of claim 3; and The discharge portion is connected to the storage body and discharges the discharge liquid stored in the discharge liquid chamber.

6. The liquid ejection device according to claim 5, characterized in that: The ejection liquid flow path has: A first connecting end connected to the storage body; and The second connecting end is connected to the storage body, The first connecting end and the second connecting end are in communication with the liquid ejection chamber. The ejection portion is located in the ejection liquid flow path.

7. The liquid ejection device according to claim 6, characterized in that: The liquid storage portion is a first liquid storage portion, The storage body is a first storage body, The liquid flow mechanism includes a second liquid storage portion, the second liquid storage portion storing the ejection liquid, or storing the ejection liquid and the moisturizing liquid, The second liquid storage part has a second storage body, and the second storage body stores the ejection liquid, or stores the ejection liquid and the moisturizing liquid. The ejection liquid flow path has: a first connecting flow path connected to the first storage body and the second storage body; and a second connecting flow path connected to the first storage body and the second storage body, The ejection portion is located in the first connecting flow path, The pressure changing mechanism comprises: a first varying unit configured to vary the pressure within the first storage body; and The second varying unit varies the pressure in the second storage body.

8. The liquid ejection device according to claim 5, wherein: The liquid flow mechanism includes a stirring portion that stirs the moisturizing liquid stored in the moisturizing liquid chamber.

9. The liquid ejection device according to claim 8, characterized in that: The stirring part has: a stirring flow path for circulating the moisturizing liquid stored in the moisturizing liquid chamber; and A stirring pump, located in the stirring flow path, The stirring flow path has: A first end connected to the storage body; and The second end is connected to the storage body, The first end and the second end are in communication with the moisturizing liquid chamber.

10. The liquid ejection device according to claim 7, characterized in that: The moisture permeable film is a first moisture permeable film, The ejection liquid chamber is a first ejection liquid chamber, The moisturizing liquid chamber is a first moisturizing liquid chamber, The second liquid storage portion includes a second moisture permeable membrane, and the second moisture permeable membrane is attached to the second storage body. The second moisture permeable membrane divides the second storage body into a second spray liquid chamber and a second moisturizing liquid chamber. The second spray liquid chamber is a space for storing the spray liquid. The second moisturizing liquid chamber is a space for storing moisturizing liquid. The second storage body stores the ejection liquid and the moisturizing liquid in such a manner that the liquid level of the ejection liquid stored in the second ejection liquid chamber and the liquid level of the moisturizing liquid stored in the second moisturizing liquid chamber are located below the upper end of the second moisture permeable membrane. The liquid flow mechanism includes a stirring portion for stirring the moisturizing liquid stored in the first moisturizing liquid chamber and the moisturizing liquid stored in the second moisturizing liquid chamber. The stirring section has a stirring flow path, and the stirring flow path allows the moisturizing liquid to circulate in the first moisturizing liquid chamber and the second moisturizing liquid chamber. The stirring flow path has: a first circulation flow path connected to the first liquid storage part and the second liquid storage part; as well as a second circulation flow path connected to the first liquid storage portion and the second liquid storage portion, The first circulation flow path is connected to the first moisturizing liquid chamber and the second moisturizing liquid chamber. The second circulation flow path communicates with the first moisturizing liquid chamber and the second moisturizing liquid chamber.

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