Tank unit, liquid discharge device, and liquid storage body

Abstract

To provide a tank unit that can prevent liquid leakage due to a change in a circumferential environment in the state that a liquid storage body is installed.SOLUTION: An atmosphere introduction part of a tank unit, to which a liquid storage body is detachably attached, has: an atmosphere introduction port; an atmosphere open port; one or more atmosphere storage parts, and one or more communication flow channels. Each atmosphere storage part has a first atmosphere communication port which is provided on a liquid storage part side in an atmosphere flow direction in the atmosphere introduction part, and a second atmosphere communication port which is provided on the atmosphere open port side. When a volume of each atmosphere storage part until the second atmosphere communication port is immersed in the inflow liquid is so made as to be an effective volume, a total value Vn of respective effective volumes in a correct placement state, a total value Vnf of volumes of a liquid capable of being stored in each communication flow channel in the correct placement state, a total value Va of a volume of a liquid storge part of the liquid storage body and a volume of the liquid storage part, and a predetermine value α more than 1 satisfy a prescribed relationship.SELECTED DRAWING: Figure 7

Description

[Technical Field]

[0001] The present disclosure relates to a tank unit, a liquid ejection device, and a liquid container. [Background technology]

[0002] Patent document 1 discloses a technology for forming an air chamber in an air communication passage in a printer that uses ink injection from an ink bottle to prevent ink filled in a sub-tank inside the printer from leaking to the outside due to air expansion inside the printer caused by changes in the temperature and altitude surrounding the printer. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2016-168721 Summary of the Invention [Problem to be solved by the invention]

[0004] There is known a liquid ejection device that is used in an attached state in which a liquid container is attached to a tank unit. Patent Document 1 does not specifically consider technology for suppressing leakage of liquid due to changes in the surrounding environment when the device is attached. [Means for solving the problem]

[0005] According to a first aspect of the present disclosure, there is provided a tank unit to which a liquid container is detachably attached. The tank unit includes a liquid storage section for storing liquid, a liquid introduction section for introducing the liquid from the liquid storage section to the liquid storage section, an atmosphere introduction section for introducing atmosphere into the liquid storage section, and a liquid outlet section for guiding the liquid toward a liquid ejection head. The liquid introduction section has an introduction flow path for supplying the liquid from the liquid storage section to the liquid storage section, the introduction flow path having an opening that opens within the liquid storage section, and the opening is configured to open at a position lower than a nozzle surface of the liquid ejection head when the liquid ejection head is in use. The atmosphere introduction section includes an atmosphere introduction port provided in the liquid storage section, an atmosphere open port that opens the atmosphere introduction section to the atmosphere, one or more atmosphere storage sections for accommodating the atmosphere, and one or more communication flow paths provided corresponding to each of the atmosphere storage sections, the communication flow paths connecting the liquid storage section to the atmosphere storage section or connecting the atmosphere storage sections to each other. The atmosphere inlet port is located above the opening when the tank unit is in an upright position. Each of the atmosphere storage sections has a first atmosphere communication port provided on the liquid storage section side in the direction of the atmosphere flow in the atmosphere inlet port, and a second atmosphere communication port provided on the atmosphere open port side in the flow direction. Each of the first atmosphere communication ports is connected to the atmosphere inlet port of the liquid storage section or the second atmosphere communication port of another of the atmosphere storage sections via a corresponding one of the communication channels. For each of the atmosphere storage sections, when the volume of the atmosphere storage section until the second atmosphere communication port is immersed in the liquid when the liquid flows into the atmosphere storage section is defined as an effective volume, the sum Vn of the effective volumes in the upright position, the sum Vnf of the volumes of the liquid that can be accumulated in each of the communication channels in the upright position, the sum Va of the volume of the liquid storage section of the liquid container and the volume of the liquid storage section, and a predetermined value α greater than 1 satisfy the relationship of the following formula (1): Vn+Vnf≧Va×α …(1)

[0006] According to a second aspect of the present disclosure, there is provided a liquid ejection device, comprising: the tank unit of the above aspect; and the liquid ejection head.

[0007] According to a third aspect of the present disclosure, there is provided a liquid storage section for storing liquid, a liquid introduction section for introducing the liquid from a liquid container into the liquid storage section, an atmosphere introduction section for introducing atmosphere into the liquid storage section, and a liquid outlet section for guiding the liquid towards a liquid ejection head, wherein the liquid introduction section has an introduction flow path for the liquid supplied from the liquid container to the liquid storage section, the introduction flow path having an opening that opens within the liquid storage section, and the opening is configured to open at a position lower than a nozzle surface of the liquid ejection head when the liquid ejection head is in a used state, and the atmosphere introduction section comprises an atmosphere introduction port provided in the liquid storage section, an atmosphere open port that opens the atmosphere introduction section to the atmosphere, and one or more atmosphere accommodation sections for accommodating the atmosphere, a liquid container detachably attached to a tank unit, the liquid container having one or more communication channels provided corresponding to each of the atmosphere storage portions, the communication channels connecting the liquid storage portion and the atmosphere storage portion or connecting the atmosphere storage portions with each other, the atmosphere inlet port being located above the opening when the tank unit is in an upright position, each of the atmosphere storage portions having a first atmosphere communication port provided on the liquid storage portion side in a flow direction of the atmosphere in the atmosphere inlet port and a second atmosphere communication port provided on the atmosphere open port side in the flow direction, each of the first atmosphere communication ports being connected via each of the communication channels to the atmosphere inlet in one liquid storage portion or the second atmosphere communication port in another of the atmosphere storage portions; For each of the atmosphere accommodating sections, when the volume of the atmosphere accommodating section until the second atmosphere communication port is immersed in the liquid when the liquid flows into the atmosphere accommodating section is defined as an effective volume, the total value Vn of the effective volumes in the normal placement state, the total value Vnf of the volumes of the liquid that can be accumulated in each of the communication flow paths in the normal placement state, the total value Va of the volume of the liquid accommodating section and the volume of the liquid storage section, and a predetermined value α that is greater than 1 satisfy the relationship of the following formula (1): Vn+Vnf≧Va×α …(1) [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a perspective view showing the configuration of a printing system. [Figure 2] FIG. [Figure 3] FIG. [Figure 4] FIG. [Figure 5] FIG. [Figure 6] 4A and 4B are diagrams illustrating details of the tip of the introduction part and the liquid supply part. [Figure 7] FIG. 2 is an explanatory diagram showing a schematic configuration of a tank unit. [Figure 8] FIG. 2 is a schematic diagram showing the general configuration of a tank unit. [Figure 9] FIG. 4 is a perspective view showing the tank unit in a normal position. [Figure 10] FIG. 10 is a first front view of the tank unit in a normal position. [Figure 11] FIG. 2 is a second front view of the tank unit in the upright position. [Figure 12] FIG. 10 is an explanatory diagram showing the tank unit and cartridge in a first inverted state. [Figure 13] FIG. 2 is a perspective view showing the tank unit in a first inverted state. [Figure 14] FIG. 10 is a first front view of the tank unit in a first inverted state. [Figure 15] FIG. 10 is a second front view of the tank unit in the first inverted state. [Figure 16] FIG. 10 is an explanatory diagram showing the tank unit and cartridge in a second inverted state. [Figure 17] FIG. 10 is a perspective view showing the tank unit in a second inverted state. [Figure 18] FIG. 10 is a first front view of the tank unit in the second inverted state. [Figure 19] FIG. 10 is a second front view of the tank unit in the second inverted state. [Figure 20] FIG. 10 is an explanatory diagram showing the tank unit and cartridge in a third inverted state. [Figure 21] FIG. 10 is a perspective view showing the tank unit in a third inverted state. [Figure 22] FIG. 10 is a first front view of the tank unit in the third inverted state. [Figure 23] FIG. 10 is a second front view of the tank unit in the third inverted state. [Figure 24] FIG. 10 is an explanatory diagram showing the tank unit and cartridge in a fourth inverted state. [Figure 25] FIG. 10 is a perspective view showing the tank unit in a fourth inverted state. [Figure 26] FIG. 10 is a first front view of the tank unit in the fourth inverted state. [Figure 27] FIG. 10 is a second front view of the tank unit in the fourth inverted state. [Figure 28] FIG. 10 is an explanatory diagram showing the tank unit and cartridge in a fifth inverted state. [Figure 29] FIG. 10 is a perspective view showing the tank unit in a fifth inverted state. [Figure 30] FIG. 10 is a first front view of the tank unit in the fifth inverted state. [Figure 31] A second front view of the tank unit in the fifth inverted state. DETAILED DESCRIPTION OF THE INVENTION

[0009] A. First embodiment: FIG. 1 is a perspective view showing the configuration of a printing system 1 according to an embodiment of the present disclosure. FIG. 1 depicts three mutually orthogonal spatial axes, the X, Y, and Z axes. The directions of the X, Y, and Z arrows indicate the positive directions along the X, Y, and Z axes, respectively. The positive directions along the X, Y, and Z axes are referred to as the +X direction, +Y direction, and +Z direction, respectively. The directions opposite to the directions of the X, Y, and Z arrows are the negative directions along the X, Y, and Z axes, respectively. The negative directions along the X, Y, and Z axes are referred to as the -X direction, -Y direction, and -Z direction, respectively. The directions along the X, Y, and Z axes, regardless of whether they are positive or negative, are referred to as the X direction, Y direction, and Z direction, respectively. This also applies to the following figures and descriptions.

[0010] The printing system 1 includes a printing device 10 as a liquid ejection device, and a cartridge 4 as a liquid container that supplies ink, which is a liquid, to the printing device 10.

[0011] The printing device 10 of this embodiment is an inkjet printer that ejects ink as a liquid from a liquid ejection head 22. This printing device 10 is a large printer that prints on large-sized paper such as posters. The printing device 10 includes a control unit 31, a carriage 20, a liquid ejection head 22, a drive mechanism 30, and a tank unit 200 that has a liquid storage unit 210. The printing device 10 also includes operation buttons 15 that allow the user to operate the operation of the printing device 10.

[0012] The tank unit 200 has a mounting portion 6. The mounting portion 6 has a first device wall 67 located on the +Y direction side. The first device wall 67 has an insertion / removal opening 674, which is an entrance / exit to the storage chamber 61 of the cartridge 4. The cartridge 4 is stored in the storage chamber 61 of the mounting portion 6 and removed from the storage chamber 61 through this insertion / removal opening 674. A plurality of cartridges 4 are detachably mounted in the mounting portion 6. In this embodiment, four types of cartridges 4, one for each of the four colors of ink, black, yellow, magenta, and cyan, are mounted in the mounting portion 6, i.e., a total of four cartridges 4. The cartridge 4 storing black ink is also referred to as cartridge 4K, the cartridge 4 storing yellow ink is also referred to as cartridge 4Y, the cartridge 4 storing magenta ink is also referred to as cartridge 4M, and the cartridge 4 storing cyan ink is also referred to as cartridge 4C. In this embodiment, the cartridge 4K is configured to store more liquid than the cartridges 4C, 4M, and 4Y.

[0013] The printing device 10 has a replacement cover 13 on the front side in the +Y direction. The replacement cover 13 is configured to be openable and closable. Opening the replacement cover 13 reveals an opening in the mounting portion 6, allowing the cartridge 4 to be attached and detached. When the cartridge 4 is attached to the mounting portion 6, ink can be supplied to the liquid ejection head 22 provided on the carriage 20 via a tube 24 serving as a liquid circulation pipe. In this embodiment, ink is supplied from the cartridge 4 to the liquid ejection head 22 by utilizing a head difference. Specifically, ink is supplied to the liquid ejection head 22 by the head difference between the ink liquid level in the liquid storage portion 210 and the liquid ejection head 22. Note that in other embodiments, ink may be supplied to the liquid ejection head 22 by sucking ink from the cartridge 4 using a pump mechanism (not shown) of the printing device 10. Note that a tube 24 is provided for each type of ink.

[0014] The liquid ejection head 22 is provided with a nozzle for each type of ink. The liquid ejection head 22 ejects ink from the nozzles toward the printing paper 2 to print data such as characters and images. In this embodiment, the printing device 10 is a so-called "off-carriage type" printer, in which the mounting unit 6 is not linked to the movement of the carriage 20. However, the technology disclosed herein can also be applied to so-called "on-carriage type" printers, in which the mounting unit 6 is provided on the carriage 20 and moves together with the carriage 20.

[0015] The control unit 31 controls each unit of the printing device 10 and exchanges signals with the cartridge 4. The carriage 20 moves the liquid ejection head 22 relative to the printing paper 2.

[0016] The drive mechanism 30 reciprocates the carriage 20 based on control signals from the control unit 31. The drive mechanism 30 includes a timing belt 32 and a drive motor 34. By transmitting power from the drive motor 34 to the carriage 20 via the timing belt 32, the carriage 20 moves back and forth in the main scanning direction, which is along the X direction. The printing device 10 also includes a transport mechanism for moving the print paper 2 in the sub-scanning direction, which is the +Y direction. When printing is performed, the print paper 2 is moved in the sub-scanning direction by the transport mechanism, and the print paper 2 after printing is output onto the front cover 11.

[0017] Furthermore, an area called a home position is provided outside the printing area when the carriage 20 is moved in the main scanning direction, and a maintenance mechanism is mounted at the home position to perform maintenance to ensure normal printing. The maintenance mechanism is made up of a cap member 8 that is pressed against a nozzle surface 25 on the bottom side of the liquid ejection head 22 on which the nozzles are formed, forming a closed space surrounding the nozzles, an elevating mechanism (not shown) that raises and lowers the cap member 8 to press it against the nozzle surface 25 of the liquid ejection head 22, and a suction pump (not shown) that introduces negative pressure into the closed space formed by pressing the cap member 8 against the nozzle surface 25 of the liquid ejection head 22.

[0018] In this embodiment, when the printing system 1 is in use, the axis along the sub-scanning direction in which the print paper 2 is transported is defined as the Y axis, the axis along the direction of gravity is defined as the Z axis, and the axis along the movement direction of the carriage 20 is defined as the X axis. Here, the "usage state of the printing system 1" refers to a state in which the printing system 1 is installed on a horizontal surface. The "usage state of the printing system 1" corresponds to the "usage state of the liquid ejection head 22." In this embodiment, the sub-scanning direction is defined as the +Y direction, the opposite direction is defined as the -Y direction, the direction of gravity is defined as the -Z direction, and the anti-gravity direction is defined as the +Z direction. The X and Y directions are horizontal. When viewing the printing system 1 in use from the front FR side, the direction from right to left is defined as the +X direction, and the opposite direction is defined as the -X direction. In this embodiment, the insertion direction D1 in which the cartridge 4 is inserted into the cartridge mounting portion 6 for installation is defined as the -Y direction, and the removal direction D4 in which the cartridge 4 is removed from the cartridge mounting portion 6 is defined as the +Y direction. Therefore, the -Y direction side of the mounting portion 6 is also referred to as the back side, and the +Y direction side is also referred to as the front side. In this embodiment, the arrangement direction of the multiple cartridges 4 is the X direction. Hereinafter, the usage state of the liquid ejection head 22 will also be simply referred to as the "usage state."

[0019] FIG. 2 is a first perspective view of the mounting portion 6. FIG. 3 is a second perspective view of the mounting portion 6. FIG. 2 shows the mounting portion 6 into which multiple cartridges 4 are inserted or mounted. FIG. 3 is a view from FIG. 2, with the cartridges 4 omitted. In FIG. 2, cartridges 4K, 4M, and 4C are mounted in the mounting portion 6, indicating a fully mounted state. Also, in FIG. 2, cartridge 4Y is inserted into the mounting portion 6, indicating a fully inserted state. The fully mounted state is a state in which an adapter terminal (described later) of the cartridge 4 contacts an apparatus-side terminal (described later) of the mounting portion 6, and a liquid introduction portion (described later) of the mounting portion 6 is connected to a liquid supply portion of the cartridge 4. The fully inserted state is a state in which the cartridge 4 is inserted into the mounting portion 6 in an insertion direction D1, which is horizontal. In the fully inserted state, an adapter terminal (described later) of the cartridge 4 contacts an apparatus-side terminal (described later) of the mounting portion 6, but the liquid supply portion of the cartridge 4 is not connected to the liquid introduction portion of the mounting portion 6. The cartridge 4 reaches the fully-inserted state by rotating the front portion of the cartridge 4 in the insertion direction D1 in the rotational mounting direction D2, which has a component in the direction of gravity. As described above, the cartridge 4 is inserted into the mounting portion 6 in the insertion direction D1, which is the horizontal direction, and then mounted in the mounting portion 6 by moving the front portion of the cartridge 4 in the insertion direction D1 in the rotational mounting direction D2.

[0020] The X direction of the mounting unit 6 is also referred to as the width direction, the Y direction as the depth direction, and the Z direction as the height direction. In the following, unless otherwise specified, each element will be described assuming the mounting unit 6 is in an insertion-completed state. In the mounting unit 6, the insertion-completed state is the same as the initial state in which the cartridge 4 and the adapter for the cartridge 4 are not attached.

[0021] As shown in Figure 3, the mounting portion 6 forms a storage chamber 61 in which the cartridge 4 is stored. The storage chamber 61 has a substantially rectangular parallelepiped shape. The storage chamber 61 has slots for storing the cartridges 4C, 4M, 4Y, and 4K. Each slot generally corresponds to the external shape of each of the cartridges 4C, 4M, 4Y, and 4K.

[0022] As shown in FIG. 3 , the mounting portion 6 has six device walls 62, 63, 64, 65, 66, and 67 that form the storage chamber 61. In this disclosure, the term "wall" refers to a single wall as well as a wall formed by multiple walls. The first device wall 67 forms an insertion / removal opening 674 through which the cartridge 4 passes when inserting or removing it from the storage chamber 61. The second device wall 62 forms the wall on the -Y direction side of the storage chamber 61. The second device wall 62 faces the first device wall 67 in the Y direction. The second device wall 62 is a generally vertical wall when the printing device 10 is in use.

[0023] The upper wall 63 forms the wall on the +Z direction side of the storage chamber 61. The bottom wall 64 faces the upper wall 63 in the Z direction and forms the wall on the -Z direction side of the storage chamber 61. The bottom wall 64 is formed by a support member 610. The bottom wall 64 has a plurality of first openings 614. In this embodiment, four first openings 614 are formed corresponding to the number of cartridges 4 to be installed. The upper wall 63 and the bottom wall 64 intersect with the second wall 62 and the first wall 67. In this disclosure, "intersect" or "intersect" means any of the following states: (i) a state in which two elements intersect each other and actually intersect, (ii) a state in which one element intersects with the other element when extended, and (iii) a state in which the elements intersect with each other when extended.

[0024] The first device side wall 65 forms a wall on the +X direction side of the storage chamber 61. The second device side wall 66 faces the first device side wall 65 in the X direction and forms a wall on the −X direction side of the storage chamber 61. The first device side wall 65 and the second device side wall 66 intersect with the second device wall 62, the first device wall 67, the device top wall 63, and the device bottom wall 64.

[0025] 3, the mounting section 6 further includes an apparatus-side terminal section 70, an apparatus guide section 602, a support member 610, a liquid introduction section 642, an apparatus-side positioning section 644, a fixed formation body 677, and an apparatus-side identification member 630. The apparatus-side terminal section 70, the apparatus guide section 602, the liquid introduction section 642, the apparatus-side positioning section 644, the fixed formation body 677, and the apparatus-side identification member 630 constitute mounting section elements that cooperate with the cartridge 4.

[0026] A plurality of support members 610 are provided according to the number of cartridges 4 to be installed. In this embodiment, four support members 610 are provided. They form the device bottom wall 64 on the gravity direction side of the storage chamber 61. The support members 610 support the cartridges 4 from the -Z direction side, which is the gravity direction side. The support members 610 are members extending along the Y direction. The support members 610 are concave. The support members 610 have a main wall 613 that forms the device bottom wall 64, a first support side wall 611, and a second support side wall 612. The support members 610 can rotate around a rotation fulcrum 698 located on the back side of the mounting portion 6 in the insertion direction D1 and on the gravity direction side in a rotation mounting direction D2 having a component in the gravity direction and a release direction D3 having a component in the anti-gravity direction. The release direction D3 is the direction opposite to the rotation mounting direction D2.

[0027] The main wall 613 forms a concave bottom portion located on the gravity direction side. A first device opening 614 is formed in the main wall 613. The first device opening 614 and the second device opening 626 each penetrate the main wall 613 in the thickness direction of the main wall 613.

[0028] 3, the first support side wall 611 rises in the +Z direction, which is the anti-gravity direction, from the +X direction end of the main wall 613. The second support side wall 612 rises in the +Z direction from the -X axis direction end of the main wall 613. The first support side wall 611 and the second support side wall 612 face each other in the X direction.

[0029] The device guide portion 602 guides the cartridge 4 or the adapter of the cartridge 4 in the insertion direction D1 and the removal direction D4. A device guide portion 602 is provided for each support member 610. A device guide portion 602 is provided on each of the first support side wall 611 and the second support side wall 612. The device guide portion 602 is a protrusion provided on the first support side wall 611 and the second support side wall 612. A plurality of these protrusions are arranged at intervals along the insertion direction D1.

[0030] The liquid introduction portion 642 receives the liquid from the cartridge 4. The liquid introduction portion 642 has a central axis CA1. In this embodiment, the central axis CA1 is inclined by 4° in the +Y direction with respect to the Z direction. In the fully inserted state, the liquid introduction portion 642 is not located within the storage chamber 61, but is located on the -Z direction side of the storage chamber 61. In other words, the liquid introduction portion 642 is located on the opposite side of the storage chamber 610 from the support member 610. By rotating the support member 610 in the rotational mounting direction D2 about the rotation fulcrum 698, the introduction portion tip portion 642a is positioned within the storage chamber 61 as the first device opening 614 is pushed down.

[0031] The apparatus-side positioning portion 644 is received in a liquid container positioning portion of the cartridge 4, which will be described later, and thereby restricts movement of the adapter of the cartridge 4 relative to the liquid introducing portion 642. In the fully inserted state, the apparatus-side positioning portion 644 is not located within the storage chamber 61, but is located on the -Z direction side of the storage chamber 61. In other words, the apparatus-side positioning portion 644 is located on the opposite side of the storage chamber 610 from the support member 610, with the storage chamber 61 interposed therebetween. By rotating the support member 610 about the rotation fulcrum 698 in the rotational mounting direction D2, the first apparatus opening 614 is pushed down, and the tip side of the apparatus-side positioning portion 644 is positioned within the storage chamber 61.

[0032] The device-side terminal section 70 has a plurality of device-side terminals 721 that come into contact with the liquid container terminals of the cartridge 4. The device-side terminal section 70 is provided on the −Y direction side of the support member 610, which is the rear side in the insertion direction D1.

[0033] The fixed formation body 677 is formed on the +Y direction side of the support member 610. The fixed formation body 677 is also located on the -Z direction side of the insertion / removal opening 674. Four device fixing portions (described later) are arranged on the fixed formation body 677, corresponding to the slots of the storage chamber 61. The mounting fixing portions are protrusions that engage with the adapter of the cartridge 4 to fix the movement of the cartridge 4 and maintain the mounted state. The mounted state is a state in which the cartridge 4 is mounted in the tank unit 200. Specifically, the mounted state in this embodiment is a state in which the cartridge 4 is mounted in the mounting portion 6. As shown in FIG. 3 , the fixed formation body 677 has a release portion 666 that displaces the mounting fixing portion to release the engagement between the adapter of the cartridge 4 and the adapter, corresponding to each mounting fixing portion. The release portion 666 is a plate-shaped member and is connected to the device fixing portion. When the release portion 666 is pressed down toward the gravity direction, the device fixing portion is displaced in the release direction. Hereinafter, the state in which the mounted state is released is also referred to as the non-mounted state.

[0034] The device-side identification member 630 is a plurality of ribs formed on the +Y direction side of the device-side terminal portion 70. The device-side identification member 630 is provided for each slot in the mounting portion 6 that accommodates each of the cartridges 4C, 4M, 4Y, and 4K, and the pattern shape determined by the number and positions of the ribs differs for each slot.

[0035] FIG. 4 is an exploded perspective view of cartridge 4K. FIG. 5 is a perspective view of cartridge 4K. The difference between cartridge 4K and cartridges 4Y, 4M, and 4C shown in FIGS. 1 and 2 is the volume of the liquid storage region 450. Specifically, the width of the liquid storage portion 401 of cartridge 4K is larger than the width of the liquid storage portion 401 of cartridges 4Y, 4M, and 4C, resulting in the difference in the volume of the liquid storage region 450. Because other components, such as the adapter 402, are the same in cartridge 4K and cartridges 4Y, 4M, and 4C, the detailed configuration of cartridge 4 will be described below using cartridge 4K. Note that hereinafter, cartridge 4K will also be simply referred to as cartridge 4. Unless otherwise noted, the X, Y, and Z directions in the drawings showing cartridge 4 are based on the fully inserted state in which cartridge 4 has been inserted into cartridge mounting portion 6.

[0036] As shown in Fig. 5, the cartridge 4 has a substantially rectangular parallelepiped outer shape. In the cartridge 4, the direction along the -Y direction, which is the insertion direction into the mounting portion 6, is the longitudinal direction, the X direction is the short side direction as the width direction, and the Z direction is the height direction. In the cartridge 4, the longitudinal dimension is the largest and the short side dimension is the smallest.

[0037] The cartridge 4 comprises a cartridge body 41 and a circuit board 50 attached to the cartridge body 41. In this embodiment, the cartridge body 41 is made up of two members as shown in Fig. 4. In detail, the cartridge body 41 comprises a liquid storage portion 401 and an adapter 402 attached to the liquid storage portion 401 by fitting.

[0038] The liquid storage portion 401 and the adapter 402 are each molded by, for example, injection molding a synthetic resin such as polypropylene. The liquid storage portion 401 and the adapter 402 may be made of the same material or different materials.

[0039] As shown in FIG. 4 , the liquid storage portion 401 has a storage portion outer shell 408 for storing liquid therein. The storage portion outer shell 408 forms a liquid storage area 450 therein for storing liquid. The storage portion outer shell 408 has a storage portion front wall 432, a storage portion rear wall 437, a storage portion upper wall 43, a storage portion bottom wall 431, a storage portion first side wall 45 as a side wall, and a storage portion second side wall 46 as a side wall. The walls 432, 43, 431, 45, 46, and 437 are also referred to as surfaces 432, 43, 431, 45, 46, and 437. The storage portion front wall 432, the storage portion rear wall 437, the storage portion upper wall 43, the storage portion first side wall 45, and the storage portion second side wall 46 form the outer surface of the cartridge 4. In addition, a portion of the storage portion bottom wall 431 also forms the outer surface of the cartridge 4.

[0040] The storage section front wall 432 and the storage section rear wall 437 face each other in the Y direction, which is the insertion direction. The storage section upper wall 43 and the storage section bottom wall 431 face each other in the Z direction. The Z direction is parallel to the central axis CA2, which faces the direction in which the liquid supply section 442 extends. The storage section first side wall 45 and the storage section second side wall 46 face each other in the X direction.

[0041] The accommodating section front wall 432 is located on the insertion direction D1 side in which the cartridge 4 is inserted into the mounting section 6. In other words, the accommodating section front wall 432 forms an insertion tip surface on the -Y direction side, which is the insertion direction D1 side. The accommodating section rear wall 437 forms a surface on the +Y direction side, which is the removal direction. The accommodating section upper wall 43 is located on the +Z direction side and intersects with the accommodating section front wall 432 and the accommodating section rear wall 437. The accommodating section upper wall 43 forms the upper wall of the cartridge 4. The accommodating section bottom wall 431 shown in FIG. 4 is located on the -Z direction side, which is the gravity direction side, in the mounted state. The accommodating section bottom wall 431 intersects with the accommodating section front wall 432 and the accommodating section rear wall 437.

[0042] The storage section first side wall 45 is located on the -X direction side, and the storage section second side wall 46 is located on the +X direction side. The storage section first side wall 45 and the storage section second side wall 46 respectively intersect the storage section front wall 432, the storage section rear wall 437, the storage section top wall 43, and the storage section bottom wall 431. The storage section first side wall 45 and the storage section second side wall 46 each extend along the insertion direction D1.

[0043] 4, the liquid storage portion 401 further has a liquid supply portion 442 that protrudes from the storage portion bottom wall 431 of the storage portion outer shell 408. The liquid supply portion 442 is a cylindrical member, and is in communication with a liquid storage region 450, which is the internal region of the liquid storage portion 401 that stores the liquid. In the attached state, the liquid supply portion 442 is connected to the liquid introduction portion 642, and supplies the liquid in the liquid storage region 450 to the liquid ejection head 22 of the printing device 10 via the liquid introduction portion 642. The liquid supply portion 442 has a supply portion tip portion 442a as a tip portion that forms an opening through which the liquid is led out to the outside.

[0044] As shown in FIGS. 4 and 5, the adapter 402 has an adapter shell 409 that forms the outer surface of the cartridge 4 and an insertion opening 446 formed in the adapter shell 409 .

[0045] The adapter shell 409 includes an adapter front wall 82, an adapter rear wall 87, an adapter bottom wall 84, a first adapter side wall 85, a second adapter side wall 86, and a corner portion 89. Like the storage section front wall 432, the adapter front wall 82 forms an insertion tip surface on the -Y direction side, which is the insertion direction. The adapter rear wall 87 faces the adapter front wall 82 in the Y direction. The adapter bottom wall 84 is the bottom surface of the cartridge 4. The adapter bottom wall 84 intersects with the adapter front wall 82 and the adapter rear wall 87. The adapter bottom wall 84 has the above-mentioned insertion opening 446 formed therein. When the cartridge 4 is viewed from the adapter bottom wall 84 side, the insertion opening 446 and the liquid supply portion 442 are positioned so that they overlap. In this embodiment, the liquid supply portion 442 is positioned so that the central axis CA2 of the liquid supply portion 442 passes through the insertion opening 446.

[0046] The first adapter side wall 85 intersects with the adapter bottom wall 84 and extends along the longitudinal direction of the adapter 402, i.e., the insertion direction in which the cartridge 4 is inserted into the mounting portion 6. The first adapter side wall 85 is a plate-like wall that rises from the adapter bottom wall 84 toward the liquid storage portion 401. The second adapter side wall 86 faces the first adapter side wall 85 in the X direction, which is the short side direction of the adapter 402. The second adapter side wall 86 intersects with the adapter bottom wall 84 and extends along the longitudinal direction of the adapter 402, i.e., the insertion direction in which the cartridge 4 is inserted into the mounting portion 6. The second adapter side wall 86 is a plate-like wall that rises from the adapter bottom wall 84 toward the liquid storage portion 401.

[0047] The adaptor 402 has a concave shape with the adaptor bottom wall 84 as its bottom. The side of the adaptor 402 facing the adaptor bottom wall 84 is open, and a liquid supply unit 442 is disposed inside the adaptor 402 through this opening. The part of the adaptor 402 where the liquid supply unit 442 is disposed is also referred to as a supply unit mounting portion 831.

[0048] The corner portion 89 is provided at the corner where the adapter front wall 82 and the adapter bottom wall 84 intersect. The corner portion 89 has a terminal arrangement portion 90 that is recessed inward. The circuit board 50 is attached to this terminal arrangement portion 90. The circuit board 50 has a plurality of adapter terminals 521 on its surface that come into contact with the device-side terminals 721 when the circuit board 50 is in the fully attached state.

[0049] Fig. 6 is a diagram illustrating the details of the introduction portion tip 642a of the liquid introduction portion 642 and the liquid supply portion 442 of the cartridge 4. Fig. 6 shows a state in which the liquid introduction portion 642 and the liquid supply portion 442 are not connected. That is, Fig. 6 shows the liquid introduction portion 642 and the liquid supply portion 442 in an unattached state. The introduction portion tip 642a has an internal flow path 661, an outer shell forming portion 660, and an apparatus flow path valve mechanism 680.

[0050] The outer shell forming portion 660 forms the outer shell of the liquid introduction portion 642. The internal flow path 661 communicates with the liquid storage portion 210 and allows the ink liquid to circulate. The internal flow path 661 has a liquid inlet 643 on the liquid storage portion 401 side. The liquid inlet 643 is an opening for introducing liquid from the liquid storage portion 401 to the liquid introduction portion 642. The liquid inlet 643 is located on the side of the internal flow path 661 opposite the liquid storage portion 210. In other words, the liquid inlet 643 is located on the liquid storage portion 401 side in the attached state. The outer shell forming portion 660 defines the internal flow path 661. The device flow path valve mechanism 680 opens and closes the internal flow path 661.

[0051] The device flow path valve mechanism 680 has a device-side valve seat 681, a device-side valve body 683, a seal member 685, and a device-side biasing member 687. The device-side valve body 683, the seal member 685, and the device-side biasing member 687 are arranged in the internal flow path 661.

[0052] The device-side valve seat 681 is formed by a part of the outer shell forming portion 660. The device-side valve seat 681 abuts against and separates from the device-side valve element 683 via a seal member 685. The device-side valve element 683 is a cylindrical member extending along the central axis CA1. The device-side valve element 683 has an annular opening / closing portion 683a that extends radially outward. The opening / closing portion 683a faces the device-side valve seat 681 in the direction along the central axis CA1. A seal member 685 is disposed on the side of the opening / closing portion 683a facing the device-side valve seat 681. The seal member 685 is annular. The device-side biasing member 687 biases the opening / closing portion 683a toward the device-side valve seat 681. The device-side biasing member 687 is a compression coil spring disposed on the side of the opening / closing portion 683a opposite the side on which the device-side valve seat 681 is disposed.

[0053] The liquid supply unit 442 has a supply unit flow path 461 that distributes ink as a liquid, a supply unit outer shell 460 that defines the supply unit flow path 461, and a cartridge-side valve mechanism 480 that opens and closes the supply unit flow path 461.

[0054] The supply unit outer shell 460 forms the outer shell of the liquid supply unit 442. The supply unit flow path 461 communicates with the liquid storage unit 401. The cartridge-side valve mechanism 480 is disposed within the supply unit flow path 461. The cartridge-side valve mechanism 480 has a cartridge-side valve seat 481, a cartridge-side valve body 483, and a cartridge-side biasing member 487. In the direction along the central axis CA2, the cartridge-side valve seat 481, the cartridge-side valve body 483, and the cartridge-side biasing member 487 are disposed in this order from the side closest to the supply unit tip end 442a.

[0055] The cartridge-side valve seat 481 is a portion that abuts against and separates from the cartridge-side valve body 483. The cartridge-side valve seat 481 is an annular member. The cartridge-side valve seat 481 is formed of an elastic member such as synthetic rubber or elastomer. The outer peripheral surface of the cartridge-side valve seat 481 is airtightly attached to the inner peripheral surface of the supply section flow path 461. A cartridge-side valve hole 489 that penetrates the cartridge-side valve seat 481 in a direction along the central axis CA2 is formed in the cartridge-side valve seat 481. The cartridge-side valve body 483 is a roughly cylindrical member that extends along the central axis CA2. The cartridge-side biasing member 487 biases the cartridge-side valve body 483 in a direction toward the cartridge-side valve seat 481. The cartridge-side biasing member 487 is, for example, a compression coil spring.

[0056] The state in which the liquid introduction section 642 and the liquid supply section 442 are not connected corresponds to the closed state of the supply section flow path 461 and the closed state of the internal flow path 661. Furthermore, the state in which the liquid introduction section 642 and the liquid supply section 442 are connected corresponds to the open state of the supply section flow path 461 and the open state of the internal flow path 661.

[0057] When the supply unit flow path 461 is in a closed state, the biasing force of the cartridge-side biasing member 487 causes the cartridge-side valve element 483 to abut against the cartridge-side valve seat 481, blocking the cartridge-side valve hole 489. This brings the supply unit flow path 461 into a non-communicating state. On the other hand, when the supply unit flow path 461 is in an open state, the cartridge-side valve element 483 is displaced in a direction away from the cartridge-side valve seat 481. This opens the cartridge-side valve mechanism 480, bringing the supply unit flow path 461 into a communicative state, and ink contained in the liquid storage portion 401 of the cartridge 4 is supplied to the internal flow path 661 of the liquid introduction portion 642 via the liquid supply portion 442. When the supply unit flow path 461 is in a closed state, the liquid storage portion 401 in the cartridge 4 is liquid-tightly and airtightly sealed from the outside of the liquid storage portion 401. Furthermore, when the supply section flow path 461 is in an open state, the liquid storage section 401 in the cartridge 4 can exchange fluid with the outside of the liquid storage section 401, specifically, the liquid storage section 210, only via the supply section flow path 461.

[0058] Furthermore, when the device flow path valve mechanism 680 is in a closed state, the biasing force of the device-side biasing member 687 causes the opening / closing portion 683a to abut against the device-side valve seat 681 via the seal member 685. This brings the internal flow path 661 into a non-communicating state. On the other hand, when the device flow path valve mechanism 680 is in an open state, the device-side valve element 683 is pressed by the cartridge-side valve element 483 of the liquid supply unit 442, causing it to be displaced in a direction away from the device-side valve seat 681. This opens the device flow path valve mechanism 680, bringing the internal flow path 661 into a communicative state, and ink contained in the cartridge 4 is supplied to the liquid introduction unit 642 via the liquid supply unit 442. When ink is supplied from the cartridge 4 to the printing device 10, gas-liquid exchange occurs between the cartridge 4 and the tank unit 200. Specifically, for example, while ink is supplied from the liquid supply unit 442 to the liquid introduction unit 642, air contained in the liquid storage unit 210 turns into bubbles and is supplied into the liquid storage unit 401 via the liquid introduction unit 642 and the liquid supply unit 442, thereby performing gas-liquid exchange. It can also be said that the device flow path valve mechanism 680 functions as a sealing unit that seals the liquid introduction unit 642.

[0059] Fig. 7 is an explanatory diagram showing a schematic configuration of the tank unit 200. Fig. 8 is a schematic diagram showing a schematic configuration of the tank unit 200.

[0060] As shown in FIG. 7 , the tank unit 200 includes a unit front surface 203, a unit rear surface 204, a unit bottom surface 205, and a unit top surface 206. Although not shown in FIGS. 7 and 8 , the tank unit 200 also has a unit right surface and a unit left surface. The unit front surface 203, the unit rear surface 204, the unit bottom surface 205, the unit top surface 206, the unit right surface, and the unit left surface are the front, rear, bottom, top, right, and left surfaces of the tank unit 200, respectively. The unit front surface 203 corresponds to the front surface FR of the printing system 1. That is, in this embodiment, the unit front surface 203 is located on the +Y direction side in the used state. When the tank unit 200 is viewed from the unit front surface 203 side, the unit rear surface 204, the unit bottom surface 205, the unit top surface 206, the unit right surface, and the unit left surface are the rear, bottom, top, right, and left surfaces of the tank unit 200, respectively. Hereinafter, the direction in which the unit front surface 203 and the unit rear surface 204 face each other will also be referred to as the front-rear direction. The side of the unit front surface 203 in the front-rear direction will also be referred to as the "front," and the side of the unit rear surface 204 in the front-rear direction will also be referred to as the "rear." In addition, the direction in which the unit left surface and the unit right surface face each other will also be referred to as the left-right direction. The side of the unit left surface in the left-right direction will also be referred to as the "left," and the side of the unit rear surface 204 in the left-right direction will also be referred to as the "right."

[0061] The tank unit 200 is in the normal position when the liquid ejection head 22 is in use. Figures 7 and 8 show the tank unit 200 in the normal position. As shown in Figure 7, in the normal position, the tank unit 200 is positioned with the unit lower surface 205 facing downward. Also, in the normal position, the cartridge 4 attached to the tank unit 200 is positioned above the tank unit 200 with the bottom wall of the cartridge 4, i.e., the adapter bottom wall 84, facing downward.

[0062] 7 and 8, the tank unit 200 has a tank 201 and a liquid supply mechanism 350. In this embodiment, four tanks 201 and four liquid supply mechanisms 350 are provided corresponding to the four cartridges 4. Since the basic configuration of each tank 201 is the same and the basic configuration of each liquid supply mechanism 350 is the same, the following description will focus on the tank 201 and liquid supply mechanism 350 corresponding to the cartridge 4K unless otherwise specified. The tank 201 is also referred to as a sub-tank.

[0063] The tank 201 includes a liquid storage section 210, a liquid introduction section 642, an air introduction section 250, and a liquid outlet section 290. The liquid supply mechanism 350 includes a first flow path 351, a second flow path 352, a liquid pump 353, a first opening / closing valve 354, and a second opening / closing valve 355. Note that the first flow path 351, the second flow path 352, the first opening / closing valve 354, and the second opening / closing valve 355 are omitted from FIG. 7.

[0064] The liquid storage section 210 is configured as a liquid storage chamber for storing ink as a liquid. In this embodiment, the liquid storage section 210 has a rectangular parallelepiped box shape overall. The liquid storage section 210 has a liquid storage space 211 and a liquid storage wall section 212. The liquid storage space 211 is the internal space of the liquid storage section 210. The liquid storage section 210 stores liquid in the liquid storage space 211. The liquid storage wall section 212 is a wall section that partitions the liquid storage space 211.

[0065] The liquid introduction section 642 is a section for introducing ink as a liquid from the cartridge 4 to the liquid storage section 210. The ink in the cartridge 4 is introduced into the liquid storage section 210 via an introduction channel 650. In FIG. 7, the flow of ink introduced from the cartridge 4 to the liquid storage section 210 via the liquid introduction section 642 is schematically shown by dashed arrows. The introduction channel 650 has an opening 652 that opens within the liquid storage section 210. The opening 652 is configured to open at a position lower than the nozzle surface 25 when the liquid ejection head 22 is in use. In FIG. 8, a position h2 in the Z direction of the nozzle surface 25 when in use is schematically shown by a dashed line.

[0066] As shown in FIG. 7 , the introduction flow path 650 is formed by a flow path forming portion 651. The flow path forming portion 651 is configured as a wall portion that partitions the introduction flow path 650. In this embodiment, the flow path forming portion 651 has a first wall portion 653, a second wall portion 654, a first rib 655, and a second rib 657. The first wall portion 653 and the second wall portion 654 are each configured as walls that extend in the Z direction in the usage state. The first wall portion 653 is located in front of the second wall portion 654. In the usage state, the lower end of the first wall portion 653 is located on the +Z direction side of the lower end of the second wall portion 654. In the usage state, the lower end of the first rib 655 is provided to extend obliquely from the lower end of the first wall portion 653 toward the -Y direction side and the -Z direction side. The second rib 657 is provided so as to extend obliquely from the lower end of the second wall portion 654 toward the +Y direction and the -Z direction in the in-use state. By providing oblique ribs such as the first rib 655 and the second rib 657, in the in-use state, the ink from the cartridge 4 is received by the rib and guided by the rib to the liquid storage portion 210. As a result, ink splashing up inside the liquid storage portion 210 due to the introduction of ink is suppressed, and the ink is more smoothly guided into the liquid storage portion 210.

[0067] The opening 652 is formed by an end 656 of the first rib 655 and the second wall portion 654. The end 656 corresponds to the lower end of the first rib 655 in the used state. The opening 652 opens toward the upper surface of the second wall portion 654. That is, the opening 652 opens toward the -Z direction in the used state. Furthermore, in the used state, the opening 652 opens at a height h1 that represents its position in the Z direction. A rib that forms the opening 652, such as the first rib 655 in this embodiment, is also referred to as an opening-forming rib. The opening-forming rib can also be said to be a rib that determines the height h1. Specifically, the height h1 corresponds to the height of the lowest end of the end 656 in the used state.

[0068] The liquid outlet portion 290 outputs ink as a liquid in the liquid storage portion 210 toward the liquid ejection head 22. The liquid outlet portion 290 in this embodiment has a first liquid outlet 291 and a second liquid outlet 292.

[0069] As shown in FIG. 8 , a first flow path 351 is connected to the first liquid outlet 291. A second flow path 352 is connected to the second liquid outlet 292. The first flow path 351 and the second flow path 352 are each flow paths for communicating between the liquid storage section 210 and the liquid ejection head 22. A first opening / closing valve 354 is provided in the first flow path 351. The first opening / closing valve 354 opens and closes the first flow path 351 under the control of the control unit 31. The first flow path 351 also has a bypass flow path 356. The bypass flow path 356 is a flow path that connects the liquid storage section 210 side of the first opening / closing valve 354 in the first flow path 351 to the liquid ejection head 22 side of the first opening / closing valve 354 in the first flow path 351. A liquid pump 353 is provided in the bypass flow path 356. The liquid pump 353 is driven under the control of the control unit 31, and pressurizes the liquid supplied from the liquid storage unit 210 to the liquid pump 353, and sends the pressurized liquid to the liquid ejection head 22. The second flow path 352 is provided with a second opening / closing valve 355 that opens and closes the second flow path 352.

[0070] The ink supply from the liquid storage unit 210 to the liquid ejection head 22 utilizing the above-described head difference is performed via the first flow path 351 and the second flow path 352 with the first opening / closing valve 354 and the second opening / closing valve 355 open. Furthermore, for example, by driving the liquid pump 353 with the first opening / closing valve 354 closed and the second opening / closing valve 355 open, it is possible to circulate ink between the liquid storage unit 210 and the liquid ejection head 22. In this case, the first flow path 351 functions as a supply flow path for supplying ink from the liquid storage unit 210 to the liquid ejection head 22, and the second flow path 352 functions as a recovery flow path for recovering ink from the liquid ejection head 22 to the liquid storage unit 210. This ink circulation is performed, for example, to recover air bubbles accumulated in the flow paths of the liquid supply mechanism 350 and the liquid ejection head 22 to the liquid storage unit 210. Furthermore, for example, by driving the liquid pump 353 with the first on-off valve 354 and the second on-off valve 355 closed, it is possible to forcibly discharge ink from inside the liquid ejection head 22 to the outside by ink supplied to the liquid ejection head 22 via the first flow path 351. Such forcible discharge of ink is performed, for example, to clean the liquid ejection head 22.

[0071] The atmosphere introduction section 250 is a section for introducing atmosphere into the liquid storage section 210. The atmosphere introduction section 250 has an atmosphere introduction port 255, an atmosphere open port 261, one or more atmosphere storage sections 270, one or more communication flow paths 280, and a film 310. In this embodiment, the pressure of the atmosphere introduced into the liquid storage section 210 by the atmosphere introduction section 250 is used to supply ink to the liquid ejection head 22 by the above-mentioned head difference.

[0072] Hereinafter, the direction of the flow of the air in the air introduction section 250 will also be referred to as the "flow direction." The flow direction is the direction from the atmosphere side toward the liquid storage section 210 side. The liquid storage section 210 side in the flow direction will also be referred to as the downstream side of the flow direction. The opposite side of the liquid storage section 210 in the flow direction, i.e., the atmosphere side, will also be referred to as the upstream side of the flow direction.

[0073] The atmosphere inlet 255 is an opening for introducing atmosphere into the liquid storage portion 210, and is provided in the liquid storage portion 210. The atmosphere inlet 255 is located on the most downstream side of the atmosphere inlet 250. In this embodiment, the atmosphere inlet 255 is provided in the liquid storage wall portion 212, in a right front portion of the liquid storage portion 210. The right front portion is a portion forward of the center of the liquid storage portion 210 in the front-to-rear direction and to the right of the center of the liquid storage portion 210 in the left-to-right direction. Furthermore, the atmosphere inlet 255 is located above the center of the liquid storage portion 210 in the Z direction when in the normal position.

[0074] The atmosphere inlet 255 is located above the opening 652 in the normal placement state. That is, in the normal placement state, the atmosphere inlet 255 is located above height h1. In this embodiment, this configuration of the atmosphere inlet 255 and the opening 652 enables head control at height h1 in the tank 201. Specifically, when the ink level in the liquid storage portion 210 in the normal placement state is higher than height h1, the opening 652 is blocked by the ink in the liquid storage portion 210, and air is prevented from flowing from the liquid storage portion 210 into the cartridge 4 through the opening 652. As a result, the above-mentioned gas-liquid exchange is prevented, and the introduction of ink from the cartridge 4 into the liquid storage portion 210 is prevented. On the other hand, when the ink level in the liquid storage portion 210 in the normal placement state is lower than height h1, the opening 652 is open to the atmosphere inlet 250, allowing air to flow from the liquid storage portion 210 into the cartridge 4 through the opening 652. As a result, gas-liquid exchange is permitted, and ink is introduced from the cartridge 4 into the liquid storage portion 210. By restricting and permitting such gas-liquid exchange, in this embodiment, the ink level in the liquid storage portion 210 is normally maintained at approximately height h1, and head control at height h1 is achieved. Head control is performed, for example, to stably supply ink from the cartridge 4 to the liquid ejection head 22 by utilizing the above-mentioned head difference.

[0075] The atmosphere opening port 261 is an opening for opening the atmosphere introduction section 250 to the atmosphere. The atmosphere opening port 261 is located on the most upstream side in the atmosphere introduction section 250. In this embodiment, the atmosphere opening port 261 is provided in the atmosphere accommodation section 270H, which will be described later.

[0076] The film 310 is provided to prevent leakage of liquid from the tank unit 200 through the atmosphere-opening port 261. The film 310 allows air to pass through while restricting the passage of liquid. The film 310 is formed, for example, by a moisture-permeable membrane. In this embodiment, the film 310 is provided in the film accommodating section 305. The film accommodating section 305 is provided midway through an eighth communication flow path 280H (described later). The film 310 is disposed to separate a first opening 307 on the upstream side of the film accommodating section 305 from a second opening 306 on the downstream side of the film accommodating section 305. The first opening 307 communicates with a first atmosphere-communication port 273H of the atmosphere accommodating section 270H via a film upstream-side flow path 309. The second opening 306 communicates with a second atmosphere-communication port 274G (described later) via a film downstream-side flow path 308. The film upstream side flow path 309 and the film downstream side flow path 308 are each included in the eighth communication flow path 280H.

[0077] The atmosphere accommodating section 270 is a section for accommodating the atmosphere. In this embodiment, the atmosphere introduction section 250 includes, as the atmosphere accommodating section 270, an atmosphere accommodating section 270A, an atmosphere accommodating section 270B, an atmosphere accommodating section 270C, an atmosphere accommodating section 270D, an atmosphere accommodating section 270E, an atmosphere accommodating section 270F, an atmosphere accommodating section 270G, and an atmosphere accommodating section 270H, in that order from the downstream side in the flow direction. When the atmosphere accommodating sections 270A to 270H are not particularly distinguished from one another, they are also simply referred to as the atmosphere accommodating section 270. The atmosphere accommodating sections 270A to 270G are arranged in the following order from front to rear: atmosphere accommodating section 270A, atmosphere accommodating section 270B, atmosphere accommodating section 270C, atmosphere accommodating section 270D, atmosphere accommodating section 270E, atmosphere accommodating section 270F, and atmosphere accommodating section 270G. Furthermore, the atmosphere accommodating section 270A is disposed behind the liquid storage section 210. The atmosphere accommodating section 270H is disposed above and to the right of the atmosphere accommodating section 270G so as to overlap a portion of the atmosphere accommodating section 270G.

[0078] In this embodiment, each atmosphere accommodating section 270 has an overall rectangular parallelepiped box shape. The atmosphere accommodating section 270 has an atmosphere accommodating space 271 and an atmosphere accommodating wall section 272. The atmosphere accommodating space 271 is the internal space of the atmosphere accommodating section 270. The atmosphere accommodating section 270 accommodates atmosphere in the atmosphere accommodating space 271. The atmosphere accommodating wall section 272 is a wall section that partitions the atmosphere accommodating space 271. In this embodiment, the atmosphere accommodating wall section 272 between adjacent atmosphere accommodating sections 270 is configured as a wall section common to the adjacent atmosphere accommodating sections 270. In addition, the wall section between the atmosphere accommodating section 270A and the liquid storage section 210 functions as the atmosphere accommodating wall section 272 and the liquid storage wall section 212 of the atmosphere accommodating section 270A. As will be described later, the atmosphere accommodating space 271 can accommodate ink as a liquid in addition to atmosphere.

[0079] In this embodiment, the atmosphere accommodating section 270H corresponds to an upstream accommodating section. Furthermore, the atmosphere accommodating sections 270A to 270G each correspond to a downstream accommodating section. The upstream accommodating section is the atmosphere accommodating section 270 located upstream of the film 310 among the atmosphere accommodating sections 270. The downstream accommodating section is the atmosphere accommodating section 270 located downstream of the film 310 among the atmosphere accommodating sections 270.

[0080] Each atmosphere accommodating section 270 has a first atmosphere communication port 273 and a second atmosphere communication port 274. For a given atmosphere accommodating section 270, the first atmosphere communication port 273 is provided downstream in the flow direction, i.e., on the liquid storage section 210 side. On the other hand, the second atmosphere communication port 274 is provided upstream in the flow direction, i.e., on the atmosphere open port 261 side. Hereinafter, the first atmosphere communication ports 273 of each atmosphere accommodating section 270A to 270H will also be referred to as first atmosphere communication ports 273A to 273H, respectively. Furthermore, the second atmosphere communication ports 274 of each atmosphere accommodating section 270A to 270H will also be referred to as second atmosphere communication ports 274A to 274H, respectively. In this embodiment, the second atmosphere communication port 274H corresponds to the atmosphere open port 261. The film 310 is disposed between the atmosphere opening port 261 and the second atmosphere communication port 274G in the flow direction.

[0081] The communication flow path 280 is a flow path that connects the liquid storage section 210 and the atmosphere accommodating section 270, or connects the atmosphere accommodating sections 270 to each other. In this embodiment, the atmosphere introduction section 250 has, in order from the downstream side in the flow direction, a first communication flow path 280A, a second communication flow path 280B, a third communication flow path 280C, a fourth communication flow path 280D, a fifth communication flow path 280E, a sixth communication flow path 280F, a seventh communication flow path 280G, and an eighth communication flow path 280H as the communication flow paths 280. When the first communication flow path 280A to the eighth communication flow path 280H are not particularly distinguished from one another, they are also simply referred to as communication flow paths 280.

[0082] The first communication flow path 280A communicates between the liquid storage portion 210 and the atmosphere accommodating portion 270A. The first communication flow path 280A is connected to the atmosphere inlet 255 and the first atmosphere communication port 273A of the atmosphere accommodating portion 270A. The second communication flow path 280B to the eighth communication flow path 280H each communicate between the atmosphere accommodating portions 270. The second communication flow path 280B to the eighth communication flow path 280H are each connected to the first atmosphere communication port 273 of the atmosphere accommodating portion 270 located more upstream and the second atmosphere communication port 274 of the atmosphere accommodating portion 270 located more downstream, respectively. For example, the second communication flow path 280B is connected to the first atmosphere communication port 273B of the atmosphere accommodating portion 270B and the second atmosphere communication port 274A of the atmosphere accommodating portion 270A, thereby communicating between the atmosphere accommodating portion 270B and the atmosphere accommodating portion 270A. Similarly, the third communication flow path 280C communicates the atmosphere accommodating portion 270C with the atmosphere accommodating portion 270B. The fourth communication flow path 280D communicates the atmosphere accommodating portion 270D with the atmosphere accommodating portion 270C. The fifth communication flow path 280E communicates the atmosphere accommodating portion 270E with the atmosphere accommodating portion 270D. The sixth communication flow path 280F communicates the atmosphere accommodating portion 270F with the atmosphere accommodating portion 270E. The seventh communication flow path 280G communicates the atmosphere accommodating portion 270G with the atmosphere accommodating portion 270F. The eighth communication flow path 280H communicates the atmosphere accommodating portion 270H with the atmosphere accommodating portion 270G. In this embodiment, each communication flow path 280 is configured as a flow path that bends one or more times. Specifically, each communication flow path 280 is configured as a flow path that bends at a right angle one or more times. In this embodiment, the right angle is not limited to 90 degrees, but includes a range of 80 degrees to 100 degrees.

[0083] In this embodiment, the eighth communicating flow path 280H corresponds to an upstream flow path. Furthermore, each of the first communicating flow path 280A to the seventh communicating flow path 280G corresponds to a downstream flow path. The upstream accommodating section is the communicating flow path 280 located upstream of the film 310 among the communicating flow paths 280. The downstream accommodating section is the communicating flow path 280 located downstream of the film 310 among the communicating flow paths 280.

[0084] Fig. 9 is a perspective view showing the tank unit 200 in the normal installation state. Fig. 10 is a first front view of the tank unit 200 in the normal installation state. Fig. 11 is a second front view of the tank unit 200 in the normal installation state.

[0085] The tank unit 200 in this embodiment is configured to satisfy the following formula (1): Furthermore, the tank unit 200 in this embodiment is configured to satisfy the following formulas (2), (3), and (4). Vn+Vnf≧Va×α …(1) Vi + Vif ≧ Vb × α … (2) Vnp+Vfp≧Va×α …(3) Vip+Vifp≧Vb×α …(4)

[0086] With regard to the above formula (1), the total value Vn is the total of the effective volumes of the atmosphere accommodating portions 270 in the normal placement state. The effective volume is the volume of the atmosphere accommodating portion 270 until the second atmosphere communication port 274 is immersed in the liquid when the liquid flows into the atmosphere accommodating portion 270. The total value Vnf is the total of the volumes of the liquid that can be accumulated in the communicating flow paths 280 in the normal placement state. The total value Va is the sum of the volume of the liquid accommodating portion 401 and the volume of the liquid storage portion 210. The value α is a predetermined value greater than 1.

[0087] With respect to the above formula (3), the total value Vnp is the sum of the effective volumes of the atmosphere accommodating sections 270 located between the film 310 and the atmosphere inlet 255 in the flow direction in the normal placement state. In other words, the total value Vnp corresponds to the sum of the effective volumes of the downstream accommodating sections in the normal placement state. The total value Vfp is the sum of the volumes of liquid that can be accumulated in the communication flow paths 280 located between the film 310 and the atmosphere inlet 255 in the flow direction in the normal placement state. In other words, the total value Vfp corresponds to the sum of the volumes of liquid that can be accumulated in the downstream flow paths in the normal placement state.

[0088] In FIG. 7, the volume Vac of the liquid storage portion 401 in the normal position and the volume Vat of the liquid storage portion 210 are each schematically indicated by dotted hatching. The total value Va is expressed as the sum of the volumes Vac and Vat. In FIG. 7, the total value Va is also schematically indicated by hatching sloping downward to the right. In this embodiment, the volume Vac is larger than the volume Vat. The volume Vac may be an approximate value. For example, the volume Vac may be an approximate value calculated based on the external dimensions of the cartridge 4. When an approximate value is used for the volume Vac, it is preferable that the volume Vac be larger than the actual volume of the liquid storage portion 401. Furthermore, the volume Vat may be an approximate value, similar to the volume Vac. In this embodiment, the liquid storage portion 401 and the liquid storage portion 210 are configured so that the actual volume of the liquid storage region 450 of the liquid storage portion 401 is larger than the actual volume of the liquid storage space 211 of the liquid storage portion 210.

[0089] 9 to 11, the liquid that can accumulate in each atmosphere accommodating portion 270 in the normal placement state is schematically indicated by hatching slanting downward to the right. "Liquid that can accumulate in the atmosphere accommodating portion 270" refers to the liquid that is accommodated in the atmosphere accommodating portion 270 until the second atmosphere communication port 274 of that atmosphere accommodating portion 270 is submerged due to the liquid accumulated in that atmosphere accommodating portion 270. In addition, in FIGS. 9 to 11, the effective volume that constitutes at least a portion of the total value Vn is also schematically indicated by hatching slanting downward to the right. In addition, in FIGS. 9 to 11, the liquid that can accumulate in each communication flow path 280 in the normal placement state is also schematically indicated by hatching in a dotted pattern. In addition, in FIGS. 9 to 11, the volume that constitutes at least a portion of the total value Vnf is also schematically indicated by hatching in a dotted pattern. In this embodiment, "liquid that can be accumulated in the communicating flow path 280" refers to the liquid that is stored in the communicating flow path 280 until the second atmosphere communication port 274 of the atmosphere accommodating portion 270 corresponding to that communicating flow path 280 is immersed. "The atmosphere accommodating portion 270 corresponding to the communicating flow path 280" specifically refers to the atmosphere accommodating portion 270 having the first atmosphere communication port 273 connected to that communicating flow path 280. For example, the atmosphere accommodating portion 270 corresponding to the first communicating flow path 280A is the atmosphere accommodating portion 270A having the first atmosphere communication port 273A.

[0090] At least one of the total value Vn and the total value Vnf may be set based on, for example, experimental results. In this case, for example, the total value Vn may be calculated as the sum of the maximum volumes of liquid that can be accumulated in each atmosphere accommodating portion 270 when the tank unit 200 is left standing in the upright position. Also, for example, the total value Vnf may be calculated as the sum of the maximum volumes of liquid that can be accumulated in each communication flow path 280 when the tank unit 200 is left standing in the upright position. Note that the experimental results include simulation results.

[0091] In this embodiment, the total value Vn is expressed as the sum of the effective volumes vnA, vnB, vnC, vnD, vnE, vnF, vnG, and vnH. The effective volumes vnA to vnH represent the effective volumes of the atmosphere accommodating sections 270A to 270H, respectively, in the normal installation state. In FIGS. 9 to 11, the effective volumes vnA to vnH are appropriately shown schematically. The total value Vnf is expressed as the sum of the volumes vnfA, vnfB, vnfC, vnfD, vnfE, vnfF, vnfG, and vnfH. The volumes vnfA to vnfH represent the volumes of liquid that can be accumulated in the communicating channels 280A to 280H, respectively, in the normal installation state.

[0092] In this embodiment, the total value Vnp is expressed as the sum of the effective volumes vnA, vnB, vnC, vnD, vnE, vnF, and vnG. The total value Vfp is expressed as the sum of the volumes vnfA, vnfB, vnfC, vnfD, vnfE, vnfF, and vnfG.

[0093] The value α is preferably set as a value corresponding to the expansion rate of air. Specifically, the value α is preferably set taking into account the expansion of air due to changes in environmental temperature and altitude. The term "air expansion due to changes in altitude" specifically refers to the expansion of air due to changes in atmospheric pressure accompanying changes in altitude. Here, changes in the environment, such as the environmental temperature or altitude, can cause the air in the cartridge 4 and the liquid storage portion 210 to expand, potentially causing the liquid in the tank unit 200 to leak to the outside through the air-opening port 261. To prevent this from occurring, the value α is preferably 1.2 or greater, and more preferably 1.5 or greater. On the other hand, to reduce the space required for the tank unit 200, the value α is preferably 3.0 or less. Specifically, the value α is set based on Boyle's law as the expansion rate of air when, for example, the environmental temperature changes from a first temperature to a second temperature and the altitude changes from a first altitude to a second altitude. For example, if the first temperature is 0° C., the second temperature is 30° C., the first altitude is 0 meters, and the second altitude is 3500 meters, the value α is set to 1.68.

[0094] Fig. 12 is an explanatory diagram showing the tank unit 200 and cartridge 4 in the first inverted state. Fig. 13 is a perspective view showing the tank unit 200 in the first inverted state. Fig. 14 is a first front view of the tank unit 200 in the first inverted state. Fig. 15 is a second front view of the tank unit 200 in the first inverted state.

[0095] The inverted state refers to a state in which the tank unit 200 is tilted in any direction from the orientation of the tank unit 200 in the normal installation state. The first inverted state is an inverted state in which the tank unit 200 is tilted so that the right side of the unit faces downward. As shown in FIG. 12 , the first inverted state can also be said to be a state in which the tank unit 200 is tilted so that the tank right side 208 faces downward. When the tank 201 is viewed from the unit front face 203 side, the tank right side 208 is the right side of the tank 201. In the first inverted state, the cartridge 4 attached to the tank unit 200 is positioned on the +Y direction side of the tank unit 200 with the storage section second side wall 46 facing downward.

[0096] The first inverted state corresponds to the submerged state. The submerged state refers to a state in which the tank unit 200 is inverted in a direction in which the atmosphere inlet 255 is submerged in the liquid in the liquid storage section 210. Specifically, the submerged state corresponds to an inverted state in which the atmosphere inlet 255 is submerged in a normal amount of liquid stored in the liquid storage section 210, even without taking into account the expansion of air in the liquid storage section 401 and the liquid storage section 210. The normal amount of liquid represents the amount of liquid stored in the liquid storage section 210 when the head is managed at a height h1 in the upright position. In this embodiment, the first inverted state corresponds to the submerged state because the atmosphere inlet 255 is located in the right front portion of the liquid storage section 210 as described above. In this embodiment, the tank unit 200 satisfies the above formula (2) in the first inverted state and in the third and fifth inverted states described below.

[0097] With respect to the above formula (2), the total value Vi is the sum of the effective volumes of the atmosphere accommodating sections 270 in the immersed state. The total value Vif is the sum of the volumes of liquid that can be accumulated in the communicating channels 280 in the immersed state. The total value Vb is the sum of the first upper volume and the second upper volume. The first upper volume is the volume of the portion of the liquid accommodating section 401 above the liquid inlet port 643 in the immersed state. The second upper volume is the volume of the portion of the liquid storage section 210 above the atmosphere inlet port 255 in the immersed state. The first upper volume may be an approximate value, similar to the volume Vac. The second upper volume may be an approximate value, similar to the volume Vat.

[0098] Furthermore, with regard to the above formula (4), the total value Vip is the sum of the effective volumes of the atmosphere accommodating sections 270 located between the film 310 and the atmosphere inlet 255 in the flow direction in the immersed state. In other words, the total value Vip corresponds to the sum of the effective volumes of the downstream accommodating sections in the immersed state. The total value Vifp is the sum of the volumes of liquid that can accumulate in the immersed state in the communicating flow channels 280 located between the film 310 and the atmosphere inlet 255 in the flow direction. In other words, the total value Vifp corresponds to the sum of the volumes of liquid that can accumulate in the immersed state in the downstream flow channels.

[0099] 12, the first upper volume Vbc1 of the liquid storage portion 401 and the second upper volume Vbt1 of the liquid storage portion 210 in the first inverted state are schematically indicated by dotted hatching. In the first inverted state, the total value Vb is expressed as the sum of the first upper volume Vbc1 and the second upper volume Vbt1. In other words, the total value Vb in the first inverted state is schematically indicated by dotted hatching in FIG.

[0100] In FIG. 12, the cartridge remaining region R1 in the first inverted state is indicated by cross-hatching. The "cartridge remaining region" is the region of the liquid storage region 450 that is below the lower end of the liquid inlet 643 in the inverted state. The ink stored in the cartridge remaining region remains in the cartridge remaining region without being supplied to the liquid storage portion 210. For example, in the first inverted state, the ink stored in the cartridge remaining region R1 remains in the liquid storage portion 210 without being supplied to the liquid storage portion 210. When the tank unit 200 is in the first inverted state in the attached state and with liquid stored in the cartridge 4, the region of the volume Vac of the liquid storage portion 401 that contains air is reduced by the amount of ink remaining in the cartridge remaining region R1. For example, when a sufficient amount of ink is contained in the liquid storage region 450, such as immediately after starting to use the cartridge 4, and the tank unit 200 to which the cartridge 4 is attached is in the first inverted state, the region of the first upper volume Vbc1 that contains air will be smaller by the cartridge remaining region R1. Therefore, in this case, the volume that contributes to the expansion of air out of the volume Vac of the liquid storage portion 401 corresponds to the above-mentioned first upper volume Vbc1.

[0101] As shown in FIG. 12 , in this embodiment, the volume of the region above the height hb1 of the liquid storage portion 401 is used as the first upper volume Vbc1. The height hb1 represents the height of the lower end of the liquid inlet 643 in the first inverted state. That is, in this embodiment, “above the liquid inlet 643” in the first inverted state means the region above the lower end of the liquid inlet 643. This allows the first upper volume Vbc1 to be appropriately larger than, for example, when the volume of the region above the upper end of the liquid inlet 643 or the volume of the region above the center of the liquid inlet 643 in the Z direction is used as the first upper volume Vbc1. As a result, it is possible to further prevent the liquid in the tank unit 200 from leaking to the outside through the atmosphere vent 261. In other embodiments, for example, the volume of the region above the upper end of the liquid inlet 643 or the volume of the region above the center of the liquid inlet 643 in the Z direction may be used as the first upper volume Vbc1.

[0102] 13 to 15, the liquid that can accumulate in each atmosphere accommodating section 270 in the first inverted state is schematically indicated by hatching slanting downward to the right. In FIGS. 13 to 15, the effective volume that constitutes at least a portion of the total value Vi in the first inverted state can also be represented by hatching slanting downward to the right. Also, in FIGS. 13 to 15, the liquid that can accumulate in each communication flow path 280 in the first inverted state is schematically indicated by hatching with a dotted pattern. In FIGS. 13 to 15, the volume that constitutes at least a portion of the total value Vif in the first inverted state can also be represented by hatching with a dotted pattern. The total values ​​Vi and Vif may be set based on experimental results, similar to the total values ​​Vn and Vnf. In this case, the total value Vi may be calculated as the sum of the maximum volumes of liquid that can accumulate in each atmosphere accommodating section 270 when the tank unit 200 is left stationary in an immersed state. Furthermore, for example, the total value Vif may be calculated as the total value of the maximum volumes of liquid that can be accumulated in each of the communication channels 280 when the tank unit 200 is left stationary in an immersed state.

[0103] In this embodiment, the total value Vi in the first inverted state is expressed as the sum of effective volumes viA1, viB1, viC1, viD1, viE1, viF1, viG1, and viH1. Effective volumes viA1 to viH1 represent the effective volumes of atmosphere accommodating sections 270A to 270H, respectively, in the first inverted state. Furthermore, the total value Vif in the first inverted state is expressed as the sum of volumes vifA1, vifB1, vifC1, vifD1, vifE1, vifF1, vifG1, and vifH1. Volumes vifA1 to vifH1 represent the volumes of liquid that can be accumulated in communicating channels 280A to 280H, respectively, in the first inverted state.

[0104] In this embodiment, the total value Vip in the first inverted state is expressed as the sum of the effective volumes viA1, viB1, viC1, viD1, viE1, viF1, and viG1. The total value Vifp in the first inverted state is expressed as the sum of the volumes vifA1, vifB1, vifC1, vifD1, vifE1, vifF1, and vifG1.

[0105] Figure 16 is an explanatory diagram showing the tank unit 200 and cartridge 4 in the second inverted state. Figure 17 is a perspective view showing the tank unit 200 in the second inverted state. Figure 18 is a first front view of the tank unit 200 in the second inverted state. Figure 19 is a second front view of the tank unit 200 in the second inverted state.

[0106] The second inverted state is an inverted state in which the tank unit 200 is tilted so that the left surface of the unit faces downward. As shown in Fig. 16, the second inverted state can also be said to be a state in which the tank unit 200 is tilted so that the tank left surface 207 faces downward. When the tank 201 is viewed from the unit front surface 203 side, the tank left surface 207 is the left surface of the tank 201. In the second inverted state, the cartridge 4 attached to the tank unit 200 is located on the -Y direction side of the tank unit 200 with the storage portion first side wall 45 facing downward.

[0107] The second inverted state corresponds to a non-immersed state. The non-immersed state refers to an inverted state that is not an immersed state. On the other hand, if the tank unit 200 is in the second inverted state when a relatively large amount of ink is contained in the liquid storage portion 401 and the air in the liquid storage portion 401 and the liquid reservoir 210 expands, the ink in the liquid storage portion 401 may flow into the liquid reservoir 210 without effective gas-liquid exchange occurring between the liquid storage portion 401 and the liquid reservoir 210, causing the ink in the liquid storage portion 401 to reach the air inlet 255 within the liquid reservoir 210. This is because the volume Vac of the liquid storage portion 401 is larger than the volume Vat of the liquid reservoir 210, and therefore the volume of air in the liquid storage portion 401 is larger than the volume of air in the liquid reservoir 210. 16, the ink Lq2t that has reached the atmosphere inlet 255 in this way, and the ink Lq2c that remains in the liquid storage portion 401, are indicated by dotted hatching. Therefore, in a non-immersed state, it is more preferable that the tank unit 200 be configured to prevent the ink that has reached the atmosphere inlet 255 from leaking out via the atmosphere open port 261. For example, it is preferable that the tank unit 200 be configured to satisfy the following formula (5). It is also more preferable that the tank unit 200 be configured to satisfy the following formula (6). Vi2+Vif2≧Vt2×α …(5) Vi2p+Vif2p≧Vt2×α …(6)

[0108] With respect to the above formula (5), the total value Vi2 is the sum of the effective volumes of the atmosphere containing portions 270 in the non-immersed state. The total value Vif2 is the sum of the volumes of liquid that can be accumulated in the communication channels 280 in the non-immersed state. The volume Vt2 represents the volume of air inside the liquid containing portion 401 in the non-immersed state. For example, the volume Vt2 in the second inverted state corresponds to the volume Vac minus the volume of liquid Lq2b remaining in the liquid containing region 450 in the second inverted state. Note that the total value Vi2, the total value Vif2, and the volume Vt2 may be approximate values, similar to the volume Vac and the like.

[0109] Furthermore, with regard to the above formula (6), the total value Vi2p is the sum of the effective volumes of the atmosphere accommodation sections 270 located between the film 310 and the atmosphere inlet 255 in the flow direction in a non-immersed state. In other words, the total value Vi2p corresponds to the sum of the effective volumes of the downstream accommodation sections in a non-immersed state. The total value Vif2p is the sum of the volumes of liquid that can accumulate in the communication flow channels 280 located between the film 310 and the atmosphere inlet 255 in the flow direction in a non-immersed state. In other words, the total value Vif2p corresponds to the sum of the volumes of liquid that can accumulate in the downstream flow channels in a non-immersed state.

[0110] 12 shows an example in which liquid in the region RE above height hb2 in the liquid storage unit 401 flows into the liquid storage unit 210. Height hb2 represents the height of the center of the liquid inlet port 643 in the Z direction in the second inverted state. For example, the volume of region RE is preferably used as the volume Vt2 in the above formula (5). Here, if the liquid inlet port 643 is not blocked by liquid, gas-liquid exchange occurs between the liquid storage unit 401 and the liquid storage unit 210, stopping the preferential flow of ink from the liquid storage unit 401 into the liquid storage unit 210. This preferential flow of ink may not stop when the ink level in the liquid storage unit 401 drops to the top of the liquid inlet port 643. This is due to, for example, a meniscus that may form in the internal flow channel 661. Therefore, as described above, by setting the region RE as a region above the height hb2, the volume Vt can be appropriately increased, and the occurrence of a situation in which the liquid in the tank unit 200 may leak to the outside through the atmospheric opening 261 can be further prevented.

[0111] 17 to 19, the liquid that can accumulate in each atmosphere accommodating section 270 in the second inverted state is schematically indicated by hatching slanting downward to the right, similarly to Figures 13 to 15. Also, in Figures 17 to 19, the liquid that can accumulate in each communication flow path 280 in the first inverted state is schematically indicated by hatching with a dotted pattern.

[0112] In the following, the effective volumes of atmosphere accommodating section 270A to atmosphere accommodating section 270H in the second inverted state are also referred to as effective volumes viA2, viB2, viC2, viD2, viE2, viF2, viG2, and viH2, respectively. In the second inverted state, the volumes of liquid that can be accumulated in communicating channels 280A to 280H are also referred to as volumes vifA2, vifB2, vifC2, vifD2, vifE2, vifF2, vifG2, and vifH2, respectively.

[0113] In this embodiment, the total value Vi2 in the second inverted state is expressed as the sum of the effective volumes viA2, viB2, viC2, viD2, viE2, viF2, viG2, and viH2. Furthermore, the total value Vif2 in the second inverted state is expressed as the sum of the volumes vifA2, vifB2, vifC2, vifD2, vifE2, vifF2, vifG2, and vifH2. Furthermore, in this embodiment, the total value Vi2p in the second inverted state is expressed as the sum of the effective volumes viA2, viB2, viC2, viD2, viE2, viF2, and viG2. Furthermore, the total value Vif2p in the second inverted state is expressed as the sum of the volumes vifA2, vifB2, vifC2, vifD2, vifE2, vifF2, and vifG2.

[0114] Figure 20 is an explanatory diagram showing the tank unit 200 and cartridge 4 in the third inverted state. Figure 21 is a perspective view showing the tank unit 200 in the third inverted state. Figure 22 is a first front view of the tank unit 200 in the third inverted state. Figure 23 is a second front view of the tank unit 200 in the third inverted state.

[0115] The third inverted state is an inverted state in which the tank unit 200 is tilted so that the unit upper surface 206 faces downward. In the third inverted state, the cartridge 4 attached to the tank unit 200 is positioned on the -Z direction side of the tank unit 200 with the storage section upper wall 43 facing downward. The third inverted state corresponds to the immersed state. In this embodiment, since the air inlet 255 is located in the right front portion of the liquid storage section 210 as described above, the third inverted state corresponds to the immersed state.

[0116] In Figure 20, the second upper volume Vbt3 of the liquid storage portion 210 in the third inverted state is schematically indicated by a dashed line and dotted hatching. The first upper volume Vbc3 of the liquid storage portion 401 in the third inverted state is zero. Therefore, in the third inverted state, the above total value Vb corresponds to the second upper volume Vbt3. In Figure 20, the total value Vb in the third inverted state can also be said to be schematically indicated by hatching sloping downward to the right.

[0117] In the third inverted state, when atmospheric air inlet 255 is actually immersed in the ink in liquid storage section 210, the liquid storage section 401 and the area in liquid storage section 210 up to height h3 of atmospheric air inlet 255 are filled with ink. On the other hand, if the amount of ink in liquid storage section 210 and liquid storage section 401 is relatively small and the ink does not reach height h3 in the third inverted state, atmospheric air inlet 255 is not actually immersed in the ink in liquid storage section 210.

[0118] 21 to 23, the liquid that can accumulate in each atmosphere accommodating portion 270 in the third inverted state is schematically indicated by hatching slanting downward to the right. In addition, in FIGS. 21 to 23, the liquid that can accumulate in each communication flow path 280 in the third inverted state is schematically indicated by hatching in a dotted pattern. In addition, in FIGS. 21 to 23, the volume ...

[0119] In this embodiment, the total value Vi in the third inverted state is expressed as the sum of the effective volumes viA3, viB3, viC3, viD3, viE3, viF3, viG3, and viH3. The effective volumes viA3 to viH3 represent the effective volumes of atmosphere accommodating sections 270A to 270H, respectively, in the third inverted state. Note that in this embodiment, the effective volumes viB3, viC3, viD3, and viH3 are each zero. The total value Vif in the third inverted state is expressed as the sum of the volumes vifA3, vifB3, vifC3, vifD3, vifE3, vifF3, vifG3, and vifH3. The volumes vifA3 to vifH3 represent the volumes of liquid that can be accumulated in communicating channels 280A to 280H, respectively, in the third inverted state.

[0120] In this embodiment, the total value Vip in the third inverted state is expressed as the sum of the effective volumes viA3, viB3, viC3, viD3, viE3, viF3, and viG3. The total value Vifp in the third inverted state is expressed as the sum of the volumes vifA3, vifB3, vifC3, vifD3, vifE3, vifF3, and vifG3.

[0121] Figure 24 is an explanatory diagram showing the tank unit 200 and cartridge 4 in the fourth inverted state. Figure 25 is a perspective view showing the tank unit 200 in the fourth inverted state. Figure 26 is a first front view of the tank unit 200 in the fourth inverted state. Figure 27 is a second front view of the tank unit 200 in the fourth inverted state.

[0122] The fourth inverted state is an inverted state in which the tank unit 200 is tilted so that the unit rear surface 204 faces downward, i.e., so that the unit front surface 203 faces upward. In the fourth inverted state, the cartridge 4 attached to the tank unit 200 is positioned on the -Y direction side of the tank unit 200 with the storage section front wall 432 facing downward. The fourth inverted state corresponds to a non-immersed state.

[0123] In FIG. 24, the cartridge remaining region R4 in the fourth inverted state is indicated by dotted hatching. Specifically, the cartridge remaining region R4 is a region of the liquid storage region 450 whose height is equal to or less than height h4. Height h4 is the height of the lower end of the liquid inlet port 643 in the fourth inverted state. Also in FIG. 24, the tank remaining region Rt4 in the fourth inverted state is indicated by dotted hatching. The "tank remaining region" is a region of the liquid storage space 211 that is lower than the lower end of the liquid inlet port 643 and the air inlet port 255 in the inverted state. Ink stored in the tank remaining region remains in the tank remaining region without being recovered into the cartridge 4. Specifically, the tank remaining region Rt4 is a region of the liquid storage space 211 whose height is equal to or less than height h4. Note that in the fourth inverted state, as in the second inverted state, the tank unit 200 may be configured to satisfy the above formula (5). In addition, in the fourth inverted state, the tank unit 200 may be configured to satisfy the above formula (6).

[0124] 25 to 27, similarly to Figures 13 to 15, the liquid that can accumulate in each atmosphere accommodating section 270 in the fourth inverted state is schematically indicated by hatching slanting downward to the right. Also, in Figures 24 to 27, the liquid that can accumulate in each communication flow path 280 in the fourth inverted state is schematically indicated by hatching with a dotted pattern.

[0125] In the following, the effective volumes of atmosphere accommodating section 270A to atmosphere accommodating section 270H in the fourth inverted state are also referred to as effective volumes viA4, viB4, viC4, viD4, viE4, viF4, viG4, and viH4, respectively. In this embodiment, effective volumes viA4, viB4, viD4, viE4, and viF4 are all zero. In the second inverted state, the volumes of liquid that can be accumulated in communicating channels 280A to 280H are also referred to as volumes vifA4, vifB4, vifC4, vifD4, vifE4, vifF4, vifG4, and vifH4, respectively.

[0126] In this embodiment, the total value Vi2 in the fourth inverted state is expressed as the sum of the effective volumes viA4, viB4, viC4, viD4, viE4, viF4, viG4, and viH4. Furthermore, the total value Vif2 in the fourth inverted state is expressed as the sum of the volumes vifA4, vifB4, vifC4, vifD4, vifE4, vifF4, vifG4, and vifH4. Furthermore, in this embodiment, the total value Vi2p in the fourth inverted state is expressed as the sum of the effective volumes viA4, viB4, viC4, viD4, viE4, viF4, and viG4. Furthermore, the total value Vif2p in the fourth inverted state is expressed as the sum of the volumes vifA4, vifB4, vifC4, vifD4, vifE4, vifF4, and vifG4.

[0127] Figure 28 is an explanatory diagram showing the tank unit 200 and cartridge 4 in the fifth inverted state. Figure 29 is a perspective view showing the tank unit 200 in the fifth inverted state. Figure 30 is a first front view of the tank unit 200 in the fifth inverted state. Figure 31 is a second front view of the tank unit 200 in the fifth inverted state.

[0128] The fifth inverted state is an inverted state in which the tank unit 200 is tilted so that the unit front surface 203 faces downward. In the fifth inverted state, the cartridge 4 attached to the tank unit 200 is positioned on the +Y direction side of the tank unit 200 with the storage section rear wall 437 facing downward. The fifth inverted state corresponds to the immersed state.

[0129] In FIG. 28, the first upper volume Vbc5 of the liquid storage portion 401 and the second upper volume Vbt5 of the liquid storage portion 210 in the fifth inverted state are schematically indicated by dotted hatching. Specifically, the first upper volume Vbc5 is the volume of the liquid storage area 450 above height h6. Height h6 represents the height of the lower end of the liquid inlet port 643 in the fifth inverted state. The second upper volume Vbt5 is the volume of the liquid storage space 211 above height h5. Height h5 represents the height of the air inlet port 255 in the fifth inverted state. In the fifth inverted state, the total value Vb is represented as the sum of the first upper volume Vbc5 and the second upper volume Vbt5. In FIG. 28, the total value Vb in the fifth inverted state is also represented by dotted hatching.

[0130] 28, the cartridge remaining region R5 in the fifth inverted state is schematically shown by hatching slanting downward to the right. Specifically, the cartridge remaining region R5 is the region of the liquid storage region 450 whose height is equal to or less than height h6. Also, in FIG. 28, the tank remaining region Rt5 in the fifth inverted state is shown by hatching slanting downward to the right. Specifically, the tank remaining region Rt5 is the region of the liquid storage space 211 whose height is equal to or less than height h5.

[0131] 29 to 31, the liquid that can accumulate in each atmosphere accommodating portion 270 in the fifth inverted state is schematically indicated by hatching slanting downward to the right. In other words, the effective volume that constitutes at least a portion of the total value Vi in the fifth inverted state is represented by hatching slanting downward to the right. Also, in FIGS. 29 to 31, the liquid that can accumulate in each communication flow path 280 in the fifth inverted state is schematically indicated by hatching in a dotted pattern. In other words, the volume that constitutes at least a portion of the total value Vif in the fifth inverted state is represented by hatching in a dotted pattern.

[0132] In this embodiment, the total value Vi in the fifth inverted state is expressed as the sum of effective volumes viA5, viB5, viC5, viD5, viE5, viF5, viG5, and viH5. Effective volumes viA5 to viH5 represent the effective volumes of atmosphere accommodating sections 270A to 270H, respectively, in the fifth inverted state. Furthermore, the total value Vif is expressed as the sum of volumes vifA5, vifB5, vifC5, vifD5, vifE5, vifF5, vifG5, and vifH5. Volumes vifA5 to vifH5 represent the volumes of liquid that can be accumulated in communicating channels 280A to 280H, respectively, in the fifth inverted state.

[0133] In this embodiment, the total value Vip in the fifth inverted state is expressed as the sum of the effective volumes viA5, viB5, viC5, viD5, viE5, viF5, and viG5. The total value Vifp in the fifth inverted state is expressed as the sum of the volumes vifA5, vifB5, vifC5, vifD5, vifE5, vifF5, and vifG5.

[0134] According to the tank unit 200 of this embodiment described above, each part of the tank unit 200 is configured to satisfy the relationship of the above formula (1). In this way, even if the air inside the cartridge 4 and the liquid storage portion 210 expands in response to the surrounding environment in the attached state, the ink inside the liquid storage portion 210 is prevented from passing through the atmosphere introduction portion 250 and reaching the atmosphere open port 261. Therefore, in the attached state, it is possible to prevent a situation from occurring in which liquid may leak outside the tank unit 200 due to changes in the surrounding environment.

[0135] Furthermore, in this embodiment, each part of the tank unit 200 is configured to satisfy the relationship of formula (2) above. Specifically, each part of the tank unit 200 is configured to satisfy the relationship of formula (2) above in the first inverted state, the third inverted state, and the fifth inverted state. This further reduces the likelihood of liquid leaking out of the tank unit 200 due to changes in the surrounding environment, even in the immersed state. Therefore, in the attached state, it is possible to effectively reduce the likelihood of liquid leaking out of the tank unit 200 due to changes in the surrounding environment. Specifically, for example, it is possible to effectively reduce the likelihood of liquid leaking out even when the tank unit 200 is immersed during transportation of the printing system 1.

[0136] Furthermore, in this embodiment, the various components of the tank unit 200 are configured to satisfy the relationship of the above formula (3). In this manner, even if the air in the cartridge 4 and the liquid storage portion 210 expands in response to changes in the surrounding environment in the attached state, the ink in the liquid storage portion 210 is prevented from passing through the air introduction portion 250 and reaching the film 310. Therefore, in the attached state, it is possible to prevent the liquid in the tank unit 200 from adhering to the film 310 due to changes in the surrounding environment.

[0137] Furthermore, in this embodiment, each part of tank unit 200 is configured to satisfy the relationship of formula (4) above. Specifically, each part of tank unit 200 is configured to satisfy the relationship of formula (4) above in the first inverted state, the third inverted state, and the fifth inverted state. In this way, even in the immersed state, for example, it is possible to prevent the liquid in tank unit 200 from adhering to film 310 due to changes in the surrounding environment.

[0138] Furthermore, in this embodiment, the atmosphere accommodating section 270H is provided on the upstream side of the film 310, and the atmosphere accommodating section 270H is provided with the atmosphere open port 261. Therefore, for example, even if liquid flows into the tank unit 200 through the atmosphere open port 261 during manufacturing of the tank unit 200 or the printing device 10, it is possible to prevent the flowing liquid from adhering to the film 310.

[0139] Furthermore, in this embodiment, the atmosphere introduction part 250 has two or more atmosphere accommodating parts 270 and two or more communication flow paths 280. This makes it possible to more effectively prevent the occurrence of a situation in which liquid may leak to the outside of the tank unit 200 due to changes in the surrounding environment in the attached state, compared to, for example, a configuration in which only one atmosphere accommodating part 270 and one communication flow path 280 is provided.

[0140] In this embodiment, in the first attitude of the tank unit 200, the effective volume of the first atmosphere accommodation section of each atmosphere accommodation section 270 is larger than the effective volume of the second atmosphere accommodation section, and in the second attitude of the tank unit 200, the effective volume of the first atmosphere accommodation section is larger than the effective volume of the second atmosphere accommodation section. The second attitude is a different attitude from the first attitude. The second atmosphere accommodation section is an atmosphere accommodation section 270 of each atmosphere accommodation section 270 that is different from the first atmosphere accommodation section. For example, as shown in FIGS. 9 to 11, in the upright position, the effective volume vnC of the atmosphere accommodation section 270C is larger than the effective volumes vnA, vnB, vnD, vnE, vnF, vnG, and vnH of the other atmosphere accommodation sections 270 that are different from the atmosphere accommodation section 270C. 13 to 15, in the first inverted state, the effective volume viC1 of the atmosphere accommodating section 270C is larger than the effective volumes viA1, viB1, viD1, viE1, viF1, viG1, and viH1. Also, as shown in FIGS. 25 to 27, the effective volume viC4 of the atmosphere accommodating section 270C is larger than the effective volumes viA4, viB4, viD4, viE4, viF4, viG4, and viH4. Also, as shown in FIGS. 29 to 31, on the other hand, in the second inverted state, as shown in FIGS. 17 to 19, for example, the effective volume viC2 of the atmosphere accommodating section 270C is smaller than the effective volumes viA2, viB2, viE2, viF2, and viG2. 21 to 23, in the third inverted state, the effective volume viC3 of the atmosphere accommodating section 270C is zero and is smaller than the effective volumes viA3, viE3, viF3, and viG3. As a result, in the upright position, the first inverted position, and the fourth inverted position, the effective volume of the atmosphere accommodating section 270C is relatively large, thereby ensuring a larger effective volume for the entire tank unit 200. On the other hand, when the effective volume of the atmosphere accommodating section 270C is relatively small, as in the second inverted position and the third inverted position, the effective volume of the atmosphere accommodating section 270C can be supplemented by the effective volumes of the other atmosphere accommodating sections 270, thereby ensuring a larger effective volume for the entire tank unit 200. In this way, even when the tank unit 200 is in various positions in the attached state, it is possible to prevent a situation in which liquid in the tank unit 200 leaks due to changes in the surrounding environment.

[0141] Furthermore, in this embodiment, tank unit 200 is configured to satisfy formula (5) above in the second inverted state and the fourth inverted state. Therefore, in a non-immersed state such as the second inverted state or the fourth inverted state, it is possible to effectively prevent a situation in which liquid may leak. Furthermore, in this embodiment, tank unit 200 is configured to satisfy formula (6) above in the second inverted state and the fourth inverted state. Therefore, in a non-immersed state, it is possible to prevent liquid in tank unit 200 from adhering to film 310 due to changes in the surrounding environment.

[0142] B. Other Embodiments: (B-1) In the above embodiment, the tank unit 200 is configured to satisfy the above formula (2) in the first inverted state, the third inverted state, and the fifth inverted state. In contrast, the tank unit 200 may be configured to satisfy the above formula (2) in, for example, only one or two of the first inverted state, the third inverted state, and the fifth inverted state. Furthermore, the tank unit 200 does not have to be configured to satisfy the formula (2). Similarly, the tank unit 200 may be configured to satisfy the above formula (4) in, for example, only one or two of the first inverted state, the third inverted state, and the fifth inverted state. Furthermore, the tank unit 200 does not have to be configured to satisfy the formula (4).

[0143] (B-2) In the above embodiment, the atmosphere introduction section 250 has two or more atmosphere accommodating sections 270 and two or more communication flow paths 280. In contrast, the atmosphere introduction section 250 may have only one atmosphere accommodating section 270. Furthermore, the atmosphere introduction section 250 may have only one communication flow path 280.

[0144] (B-3) In the above embodiment, the tank unit 200 is configured to satisfy the above formula (3). However, the tank unit 200 does not have to be configured to satisfy the formula (3). Furthermore, the tank unit 200 does not have to have the film 310, for example.

[0145] (B-4) In the above embodiment, the tank unit 200 is configured so that the effective volume of the first atmosphere accommodation section is larger than the effective volume of the second atmosphere accommodation section in the first posture, and so that the effective volume of the first atmosphere accommodation section is smaller than the effective volume of the second atmosphere accommodation section in the second posture. However, the tank unit 200 does not have to be configured in this way.

[0146] (B-5) In the above embodiment, the tank unit 200 may be configured to satisfy, for example, formula (1) in various inverted states. Also, the tank unit 200 may be configured to satisfy, for example, formula (3) in various inverted states.

[0147] (B-6) In the above embodiment, the liquid container is configured as a cartridge 4 having a substantially rectangular parallelepiped shape, but this is not limiting and the liquid container may be configured as various types of containers capable of containing liquid. For example, the liquid container may be configured as a bottle having a cylindrical shape or the like.

[0148] (B-7) The present disclosure is not limited to inkjet printers and their ink cartridges, but can also be applied to any printing device that ejects liquid other than ink and its cartridge. For example, the present disclosure can be applied to various printing devices and their cartridges, such as the following: (1) Image recording devices such as facsimile machines (2) A printing device that sprays color materials used in the manufacture of color filters for image display devices such as liquid crystal displays. (3) A printing device that sprays electrode materials used to form electrodes in organic EL (Electro Luminescence) displays, surface-emitting displays (Field Emission Displays, FEDs), etc. (4) A printing device that sprays liquid containing bioorganic substances used in biochip manufacturing. (5) Sample printing device as a precision pipette (6) Lubricant printing device (7) Resin liquid printing device (8) A printing device that injects lubricating oil into precision machinery such as watches and cameras. (9) A printing device that sprays transparent resin liquid, such as ultraviolet curing resin liquid, onto a substrate to form minute hemispherical lenses (optical lenses) used in optical communication elements, etc. (10) A printing device that sprays acidic or alkaline etching liquid to etch substrates, etc. (11) A printing device equipped with a liquid ejection head that ejects any other minute amount of liquid droplets

[0149] The term "droplet" refers to the state of liquid ejected from a printing device, including droplets, tears, and string-like droplets. The term "liquid" as used herein refers to any material that can be ejected by a printing device. For example, "liquid" refers to any material in its liquid phase, including materials with high or low viscosity, as well as liquid materials such as sols, gel water, other inorganic solvents, organic solvents, solutions, liquid resins, and liquid metals. The term "liquid" also includes not only liquids as a single state of matter, but also particles of functional materials composed of solids such as pigments and metal particles dissolved, dispersed, or mixed in a solvent. Representative examples of liquids include inks and liquid crystals, as described in the above embodiments. Here, "ink" encompasses various liquid compositions, such as general water-based inks and oil-based inks, as well as gel inks and hot-melt inks.

[0150] C. Other forms: The present disclosure is not limited to the above-described embodiments and can be realized in various forms without departing from the spirit thereof. For example, the present disclosure can also be realized in the following forms. The technical features in the above embodiments corresponding to the technical features in each form described below can be appropriately replaced or combined to solve some or all of the problems of the present disclosure or to achieve some or all of the effects of the present disclosure. Furthermore, if a technical feature is not described as essential in this specification, it can be appropriately deleted.

[0151] (1) According to a first aspect of the present disclosure, there is provided a tank unit to which a liquid container is detachably attached. The tank unit includes a liquid storage section for storing liquid, a liquid introduction section for introducing the liquid from the liquid storage section to the liquid storage section, an atmosphere introduction section for introducing atmosphere into the liquid storage section, and a liquid outlet section for guiding the liquid toward a liquid ejection head. The liquid introduction section has an introduction flow path for supplying the liquid from the liquid storage section to the liquid storage section, the introduction flow path having an opening that opens within the liquid storage section, and the opening is configured to open at a position lower than a nozzle surface of the liquid ejection head when the liquid ejection head is in use. The atmosphere introduction section includes an atmosphere introduction port provided in the liquid storage section, an atmosphere open port that opens the atmosphere introduction section to the atmosphere, one or more atmosphere storage sections for accommodating the atmosphere, and one or more communication flow paths provided corresponding to each of the atmosphere storage sections, the communication flow paths connecting the liquid storage section to the atmosphere storage section or connecting the atmosphere storage sections to each other. The atmosphere inlet port is located above the opening when the tank unit is in an upright position. Each of the atmosphere storage sections has a first atmosphere communication port provided on the liquid storage section side in the direction of the atmosphere flow in the atmosphere inlet port, and a second atmosphere communication port provided on the atmosphere open port side in the flow direction. Each of the first atmosphere communication ports is connected to the atmosphere inlet port of the liquid storage section or the second atmosphere communication port of another of the atmosphere storage sections via a corresponding one of the communication channels. For each of the atmosphere storage sections, when the volume of the atmosphere storage section until the second atmosphere communication port is immersed in the liquid when the liquid flows into the atmosphere storage section is defined as an effective volume, the sum Vn of the effective volumes in the upright position, the sum Vnf of the volumes of the liquid that can be accumulated in each of the communication channels in the upright position, the sum Va of the volume of the liquid storage section of the liquid container and the volume of the liquid storage section, and a predetermined value α greater than 1 satisfy the relationship of the following formula (1): Vn+Vnf≧Va×α …(1) According to this aspect, when the liquid container is attached to the tank unit, it is possible to prevent a situation from occurring in which liquid may leak out of the tank unit due to a change in the surrounding environment.

[0152] (2) In the above embodiment, the liquid introduction section has a liquid inlet port for introducing the liquid from the liquid storage section into the liquid introduction section, and the sum of the effective volumes Vi in the immersed state in which the tank unit is inverted in the liquid storage section so that the atmosphere inlet port is immersed in the liquid, the sum of the volumes Vif of the liquid that can be accumulated in the flow paths in the immersed state, and the sum of the volume of the liquid storage section above the liquid inlet port and the volume of the liquid storage section above the atmosphere inlet in the immersed state, Vb, may satisfy the relationship of the following formula (2). Vi + Vif ≧ Vb × α … (2) According to this aspect, even when the liquid container is attached to the tank unit and is immersed, it is possible to prevent a situation in which the liquid may leak out of the tank unit due to a change in the surrounding environment. Therefore, when the liquid container is attached to the tank unit, it is possible to more effectively prevent a situation in which the liquid may leak out of the tank unit due to a change in the surrounding environment.

[0153] (3) The above embodiment may further include a film for suppressing leakage of the liquid through the atmosphere opening port, the film allowing the passage of air and restricting the passage of the liquid, wherein a total value Vnp of the effective volumes of the atmosphere accommodating sections located between the film and the atmosphere inlet in the flow direction in the normal placement state and a total value Vfp of the volumes of the liquid that can be accumulated in the normal placement state in the communicating flow paths located between the film and the atmosphere inlet in the flow direction may satisfy the relationship of the following formula (3): Vnp+Vfp≧Va×α …(3) According to this aspect, when the liquid container is attached to the tank unit, it is possible to prevent the liquid in the tank unit from adhering to the film due to changes in the surrounding environment.

[0154] (4) In the above embodiment, a film for suppressing leakage of the liquid through the atmosphere opening port, which allows air to pass through and restricts the passage of the liquid, may further be provided, and the total value Vip of the effective volume in the immersed state of each of the atmosphere accommodating sections located between the film and the atmosphere inlet port in the flow direction and the total value Vifp of the volume of the liquid that can be accumulated in the immersed state in each of the communicating flow paths located between the film and the atmosphere inlet port in the flow direction may satisfy the relationship of the following formula (4). Vip+Vifp≧Vb×α …(4) According to this embodiment, even when the film 310 is immersed, it is possible to prevent the liquid in the tank unit 200 from adhering to the film 310 due to changes in the surrounding environment.

[0155] (5) In the above embodiment, the atmosphere introduction section may have two or more atmosphere storage sections and two or more communication channels. This embodiment more effectively prevents the occurrence of a situation in which the liquid may leak to the outside of the tank unit due to a change in the surrounding environment when the liquid container is attached to the tank unit.

[0156] (6) In the above aspect, the two or more atmosphere accommodating sections may include a first atmosphere accommodating section and a second atmosphere accommodating section different from the first atmosphere accommodating section, and in a first attitude of the tank unit, the effective volume of the first atmosphere accommodating section may be larger than the effective volume of the second atmosphere accommodating section, and in a second attitude of the tank unit different from the first attitude, the effective volume of the second atmosphere accommodating section may be larger than the effective volume of the first atmosphere accommodating section. According to this aspect, even when a liquid container is attached to the tank unit and the tank unit is in various attitudes, it is possible to effectively prevent the liquid in the tank unit from adhering to the film due to changes in the surrounding environment.

[0157] (7) According to a second aspect of the present disclosure, there is provided a liquid ejection device including the tank unit of the above aspect and the liquid ejection head.

[0158] (8) According to a third aspect of the present disclosure, there is provided a liquid storage section for storing liquid, a liquid introduction section for introducing the liquid from a liquid container into the liquid storage section, an atmosphere introduction section for introducing atmosphere into the liquid storage section, and a liquid outlet section for guiding the liquid toward a liquid ejection head, wherein the liquid introduction section has an introduction flow path for the liquid supplied from the liquid container to the liquid storage section, the introduction flow path having an opening that opens within the liquid storage section, and the opening is configured to open at a position lower than a nozzle surface of the liquid ejection head when the liquid ejection head is in use, and the atmosphere introduction section comprises an atmosphere introduction port provided in the liquid storage section, an atmosphere open port that opens the atmosphere introduction section to the atmosphere, and one or more atmosphere accommodation sections for accommodating the atmosphere. a liquid container detachably attached to a tank unit, the liquid container having one or more communication channels provided corresponding to each of the atmosphere storage portions, the communication channels connecting the liquid storage portion and the atmosphere storage portion or connecting the atmosphere storage portions with each other, the atmosphere inlet port being located above the opening when the tank unit is in an upright position, each of the atmosphere storage portions having a first atmosphere communication port provided on the liquid storage portion side in a flow direction of the atmosphere in the atmosphere inlet port and a second atmosphere communication port provided on the atmosphere open port side in the flow direction, each of the first atmosphere communication ports being connected via each of the communication channels to the atmosphere inlet in one liquid storage portion or the second atmosphere communication port in another atmosphere storage portion. For each of the atmosphere accommodating sections, when the volume of the atmosphere accommodating section until the second atmosphere communication port is immersed in the liquid when the liquid flows into the atmosphere accommodating section is defined as an effective volume, the total value Vn of the effective volumes in the normal placement state, the total value Vnf of the volumes of the liquid that can be accumulated in each of the communication flow paths in the normal placement state, the total value Va of the volume of the liquid accommodating section and the volume of the liquid storage section, and a predetermined value α that is greater than 1 satisfy the relationship of the following formula (1): Vn+Vnf≧Va×α …(1)

[0159] In addition to the above aspects, the present disclosure can be realized in the form of a printing system or the like. [Explanation of symbols]

[0160] 1...printing system, 2...printing paper, 4, 4C, 4K, 4M, 4Y...cartridge, 6...mounting unit, 8...cap member, 10...printing device, 11...front cover, 13...replacement cover, 15...operation button, 20...carriage, 22...liquid ejection head, 24...tube, 25...nozzle surface, 30...driving mechanism, 31...control unit, 32...timing belt, 34...driving motor, 41...cartridge Main body, 42...front wall, 43...accommodation section upper wall, 45...accommodation section first side wall, 46...accommodation section second side wall, 50...circuit board, 61...accommodation chamber, 62...second device wall, 63...device upper wall, 64...device bottom wall, 65...first device side wall, 66...second device side wall, 67...first device wall, 70...device side terminal portion, 82...adapter front wall, 84...adapter bottom wall, 85...first adapter side wall, 86...second adapter side wall, 87... Rear wall of adapter, 89...corner portion, 90...terminal arrangement portion, 200...tank unit, 201...tank, 203...unit front surface, 204...unit rear surface, 205...unit bottom surface, 206...unit top surface, 207...tank left surface, 208...tank right surface, 210...liquid storage portion, 211...liquid storage space, 212...liquid storage wall portion, 250...atmospheric inlet portion, 255...atmospheric inlet port, 261...open to atmosphere 270...atmosphere accommodating portion, 270A, 270B, 270C, 270D, 270E, 270F, 270G, 270H...atmosphere accommodating portion, 271...atmosphere accommodating space, 272...atmosphere accommodating wall portion, 273, 273A, 273B, 273C, 273D, 273E, 273F, 273G, 273H...first atmosphere communication port, 274, 274A, 274B, 274C, 274D, 274E, 274F, 274G,274H...second atmosphere communication port, 280...communication flow path, 280A...first communication flow path, 280B...second communication flow path, 280C...third communication flow path, 280D...fourth communication flow path, 280E...fifth communication flow path, 280F...sixth communication flow path, 280G...seventh communication flow path, 280H...eighth communication flow path, 290...liquid outlet section, 291...first liquid outlet port, 292...second liquid outlet port, 305...film accommodating section, 306...second opening, 307...first opening, 308...film downstream side flow path, 309...film upstream side flow path, 310...film, 350...liquid supply mechanism, 351...first flow path, 352...second flow path, 353...liquid pump, 354...first opening / closing valve, 355...second opening / closing valve, 356...bypass flow path, 401...liquid storage section, 402...adapter, 408...storage section outer shell, 409...adapter outer shell, 431...storage section bottom wall, 432...storage section front wall, 437...storage section rear wall, 442...liquid supply section, 442a...supply section tip, 446...insertion opening, 450...liquid storage area, 460...supply section outer shell, 461... Supply section flow path, 480... cartridge side valve mechanism, 481... cartridge side valve seat, 483... cartridge side valve body, 487... cartridge side biasing member, 489... cartridge side valve hole, 521... adapter terminal, 602... device guide section, 610... support member, 611... first support side wall, 612... second support side wall, 613... main wall, 614... first device opening, 626... second device opening, 630... device side identification member, 642... liquid introduction section, 642a... introduction section tip, 644... device side positioning section, 650...introduction flow path, 651...flow path forming portion, 652...opening portion, 653...first wall portion, 654...second wall portion, 655...first rib, 656...end portion, 657...second rib, 660...outer shell forming portion, 661...internal flow path, 666...releasing portion, 674...insertion / removal opening portion, 677...fixed forming body, 680...device flow path valve mechanism, 681...device side valve seat, 683...device side valve body, 683a...opening / closing portion, 685...sealing member, 687...device side biasing member, 698...rotation fulcrum, 721...device side terminal, 831...supply unit arrangement portion,

Claims

1. A tank unit to which a liquid container is detachably attached, a liquid storage section for storing a liquid; a liquid introduction portion for introducing the liquid from the liquid container into the liquid storage portion; an air inlet for introducing air into the liquid storage portion; a liquid outlet portion that outlets the liquid toward a liquid ejection head, the liquid introduction section has an introduction flow path for the liquid to be supplied from the liquid container to the liquid storage section, the introduction flow path has an opening that opens within the liquid storage portion, and the opening is configured to open at a position lower than a nozzle surface of the liquid ejection head when the liquid ejection head is in a used state; the atmosphere introduction section includes an atmosphere introduction port provided in the liquid storage section, an atmosphere open port that opens the atmosphere introduction section to the atmosphere, one or more atmosphere storage sections for accommodating the atmosphere, and one or more communication flow paths that are provided corresponding to each of the atmosphere storage sections and that communicate between the liquid storage section and the atmosphere storage section or between the atmosphere storage sections; the atmosphere inlet is disposed above the opening when the tank unit is in an upright position, each of the atmosphere storage sections has a first atmosphere communication port provided on the liquid storage section side in the flow direction of the atmosphere in the atmosphere introduction section, and a second atmosphere communication port provided on the atmosphere open port side in the flow direction, and each of the first atmosphere communication ports is connected to the atmosphere introduction port in the liquid storage section or the second atmosphere communication port in another of the atmosphere storage sections via each of the communication flow paths; a tank unit in which, for each of the atmosphere accommodating portions, when the volume of the atmosphere accommodating portion until the second atmosphere communication port is immersed in the liquid when the liquid flows into the atmosphere accommodating portion is defined as an effective volume, a total value Vn of the effective volumes in the normal placement state, a total value Vnf of the volumes of the liquid that can be accumulated in each of the communication flow paths in the normal placement state, a total value Va of the volume of the liquid accommodating portion of the liquid container and the volume of the liquid storage portion, and a predetermined value α that is greater than 1 satisfy the relationship of the following formula (1): Vn+Vnf≧Va×α…(1)

2. The tank unit according to claim 1, the liquid introduction section has a liquid introduction port for introducing the liquid from the liquid storage section into the liquid introduction section, a tank unit in which a total value Vi of each of the effective volumes in an immersed state in which the tank unit is inverted in a direction in which the atmosphere inlet in the liquid storage section is immersed in the liquid, a total value Vif of the volume of the liquid that can be accumulated in each of the flow paths in the immersed state, and a total value Vb of the volume above the liquid inlet in the liquid storage section in the immersed state and the volume above the atmosphere inlet in the liquid storage section satisfy the relationship of the following formula (2): Vi+Vif≧Vb×α…(2)

3. The tank unit according to claim 1, Further, a film for suppressing leakage of the liquid through the atmosphere opening is provided, the film allowing the passage of air and restricting the passage of the liquid, a tank unit in which a total value Vnp of the effective volumes of the atmosphere storage sections located between the film and the atmosphere inlet in the flow direction in the normal placement state and a total value Vfp of the volumes of the liquid that can be accumulated in the normal placement state in the communicating flow paths located between the film and the atmosphere inlet in the flow direction satisfy the relationship of the following formula (3): Vnp+Vfp≧Va×α…(3)

4. The tank unit according to claim 2, Further, a film for suppressing leakage of the liquid through the atmosphere opening is provided, the film allowing the passage of air and restricting the passage of the liquid, a tank unit in which a total value Vip of the effective volumes in the immersed state of each of the atmosphere accommodating sections located between the film and the atmosphere inlet in the flow direction, and a total value Vifp of the volumes of the liquid that can be accumulated in the immersed state in each of the communicating flow paths located between the film and the atmosphere inlet in the flow direction, satisfy the relationship of the following formula (4): Vip+Vifp≧Vb×α…(4)

5. The tank unit according to claim 1, The atmosphere introduction section has two or more of the atmosphere storage sections and two or more of the communication flow paths.

6. The tank unit according to claim 3, the two or more atmosphere accommodating sections include a first atmosphere accommodating section and a second atmosphere accommodating section different from the first atmosphere accommodating section, When the tank unit is in a first attitude, the effective volume of the first atmosphere accommodation portion is larger than the effective volume of the second atmosphere accommodation portion, A tank unit, wherein, in a second posture of the tank unit that is different from the first posture, the effective volume of the second atmosphere accommodation portion is larger than the effective volume of the first atmosphere accommodation portion.

7. The tank unit according to any one of claims 1 to 6, A liquid ejection device comprising the liquid ejection head.

8. a liquid storage section for storing a liquid; a liquid introduction portion for introducing the liquid from a liquid container into the liquid storage portion; an air inlet for introducing air into the liquid storage portion; a liquid outlet portion that outlets the liquid toward a liquid ejection head, the liquid introduction section has an introduction flow path for the liquid to be supplied from the liquid container to the liquid storage section, the introduction flow path has an opening that opens within the liquid storage portion, and the opening is configured to open at a position lower than a nozzle surface of the liquid ejection head when the liquid ejection head is in an operating state; the atmosphere introduction section includes an atmosphere introduction port provided in the liquid storage section, an atmosphere open port that opens the atmosphere introduction section to the atmosphere, one or more atmosphere storage sections for accommodating the atmosphere, and one or more communication flow paths that are provided corresponding to each of the atmosphere storage sections and that communicate between the liquid storage section and the atmosphere storage section or between the atmosphere storage sections; the atmosphere inlet is disposed above the opening when the tank unit is in an upright position, a liquid container detachably attached to a tank unit, wherein each of the atmosphere storage sections has a first atmosphere communication port provided on the liquid storage section side in a flow direction of the atmosphere in the atmosphere introduction section, and a second atmosphere communication port provided on the atmosphere open port side in the flow direction, and each of the first atmosphere communication ports is connected to the atmosphere introduction port in the liquid storage section or the second atmosphere communication port in another of the atmosphere storage sections via each of the communication flow paths, a liquid storage section for storing the liquid; a liquid container in which, when the volume of each of the atmosphere storage sections until the second atmosphere communication port is immersed in the liquid when the liquid flows into the atmosphere storage section is defined as an effective volume, a total value Vn of the effective volumes in the normal placement state, a total value Vnf of the volumes of the liquid that can be accumulated in each of the communication flow paths in the normal placement state, a total value Va of the volume of the liquid storage section and the volume of the liquid storage section, and a predetermined value α that is greater than 1 satisfy the relationship of the following formula (1): Vn+Vnf≧Va×α…(1)

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