Liquid discharge device

Abstract

To provide a liquid discharge device in which a liquid discharge port is hardly clogged with foreign matter and a cleaning liquid tank can be easily cleaned.SOLUTION: A cleaning liquid chamber 64 is provided in a housing 61 of a cleaning liquid tank 52. The cleaning liquid chamber 64 is provided with a wiper region 71, a first drain port region 72, and a second drain port region 73. The wiper region 71 and the second drain port region 73 are separated from the first drain port region 72 by a wall section 76 projecting upward from a lower surface of a cleaning liquid chamber 63. Two wiper units rotatably supported by wiper unit support sections 71A, 71B are arranged in the wiper region 71. A first drain port 75 is provided in the first drain port region 72. A second drain port 79 is provided in the second drain port region 73. The second drain port 79 is closed by a removable plug.SELECTED DRAWING: Figure 7

Description

[Technical Field]

[0001] The present invention relates to a liquid ejection device that ejects liquid from a nozzle. [Background technology]

[0002] As an example of a liquid ejection device that ejects liquid from nozzles, Patent Document 1 describes a printer that ejects ink from nozzles to print an image on a recording medium. The printer described in Patent Document 1 has a wiper for removing ink adhering to a nozzle face on which nozzles are formed, and a cleaning liquid tank located below the wiper. The wiper can be rotated around a rotation axis by a wiper movement mechanism. By rotating the wiper around the rotation axis, the wiper can be displaced between a position where it can contact the nozzle face and a position where it is immersed in cleaning liquid in the cleaning liquid tank. In addition, in the printer of Patent Document 1, a discharge flow path for discharging cleaning liquid is connected to the cleaning liquid tank. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2019-198988 Summary of the Invention [Problem to be solved by the invention]

[0004] In the printer of Patent Document 1, when ink adhering to the nozzle surface is removed with a wiper, solidified ink may adhere to the wiper. When the wiper with solidified ink adhering to it is immersed in the cleaning liquid in the cleaning liquid tank, the solidified ink accumulates in the cleaning liquid tank. As a result, when the cleaning liquid in the cleaning liquid tank is discharged from the discharge flow path, the discharge flow path may become clogged with solidified ink in the cleaning liquid tank. Therefore, in printers such as those described in Patent Document 1, cleaning of the cleaning liquid tank, for example, is required to prevent the discharge flow path from becoming clogged with solidified ink.

[0005] An object of the present invention is to provide a liquid ejection device in which foreign matter is less likely to clog the drain outlet and the cleaning liquid tank can be easily cleaned. [Means for solving the problem]

[0006] A liquid ejection device of the present invention includes a nozzle surface, a cleaning liquid tank that stores cleaning liquid or through which the cleaning liquid flows, a wiper that is displaceable between an immersion position in the cleaning liquid tank where it is immersed in the cleaning liquid and a wiping position where it can come into contact with the nozzle surface and that wipes the nozzle surface when it is positioned at the wiping position, a first drainage port that is provided in the cleaning liquid tank and that discharges the cleaning liquid in the cleaning liquid tank, and a wall portion that is provided in a portion of the cleaning liquid tank between a wiper region that includes a portion that overlaps with the wiper in the vertical direction and a first drainage port region that includes a portion where the first drainage port is provided, the wall portion protruding upward from a bottom surface of the cleaning liquid tank and separating the wiper region from the first drainage port region. The cleaning liquid tank is provided with a second drainage port that is provided separately from the first drainage port and that discharges the cleaning liquid in the cleaning liquid tank, and a plug that is removably attached to the second drainage port and that closes the second drainage port. [Effects of the Invention]

[0007] Solid matter adhering to the wiper may accumulate in the wiper area of ​​the cleaning liquid tank. Because there is a wall between the wiper area and the drain area, the cleaning liquid flows over the wall from the wiper area to the drain area, but solid matter does not easily flow from the wiper area to the drain area. This makes it less likely for solid matter to clog the first drain outlet and the flow path connected to the first drain outlet. Furthermore, by cleaning the cleaning liquid tank with the plug removed from the second drain outlet, solid matter accumulated in the cleaning liquid tank can be discharged from the second drain outlet, which is separate from the first drain outlet. This makes cleaning the cleaning liquid tank easy. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a schematic perspective view of a printing apparatus according to an embodiment of the present invention. [Figure 2]FIG. 2 is a plan view showing the internal structure of the printing device shown in FIG. [Figure 3] FIG. 2 is a front view of the printing device shown in FIG. [Figure 4] FIG. 2 is a perspective view of the cleaning liquid tank and other components with the lid in the closed position. [Figure 5] FIG. 2 is a perspective view of a part of the cleaning liquid tank when the lid is in the open position. [Figure 6] FIG. 6 is an enlarged view of the wiper region and its surroundings in FIG. 5. [Figure 7] FIG. 6 is a diagram showing the wiper unit, ink receiving plate, etc. removed from FIG. 5. [Figure 8] FIG. 10 is a plan view of the cleaning liquid tank and other components with the lid in the open position. [Figure 9] FIG. 9 is a cross-sectional view taken along line IX-IX in FIG. 8. [Figure 10] 9 is a cross-sectional view taken along line XX in FIG. 8. [Figure 11] 1A is a cross-sectional view of a section perpendicular to the rotation axis of a wiper unit, etc., for explaining the wiping position, and FIG. 1B is a cross-sectional view corresponding to FIG. 1A for explaining the immersion position. DETAILED DESCRIPTION OF THE INVENTION

[0009] <Embodiment> A printing device 1 according to one embodiment of the present invention will be described with reference to the drawings. In the following description, the up-down direction and front-rear direction are defined based on the state in which the printing device 1 is installed and ready for use, as shown in FIG. 1, and the left-right direction is defined when viewing the printing device 1 from the front. In the following description, the left-right direction may also be referred to as the main scanning direction, and the front-rear direction as the sub-scanning direction. In this embodiment, the printing device 1 corresponds to the "liquid ejection device" of the present invention.

[0010] The printing device 1 shown in Figure 1 is an inkjet printer that prints by ejecting ink onto a printing medium. The printing device 1 prints a color image on the printing medium using seven colors of ink: white, black, yellow, cyan, magenta, green, and orange. The printing medium is not particularly limited as long as it is possible to form an image by ejecting ink onto it, and examples of the printing medium include fabric and paper.

[0011] In the following, the white ink of the seven color inks will be referred to as "white ink." When referring to the six color inks of the seven color inks (black, cyan, yellow, magenta, green, and orange) collectively or when not specifying any of them, they will be referred to as "color ink." When referring to white ink and color inks collectively or when not specifying any of them, they will simply be referred to as "ink." White ink is used in printing to represent the white part of an image or as a base for color inks. Color inks are ejected on top of a base of white ink and are used to print color images.

[0012] 1 to 3, the external configuration of the printing device 1 will be described. As shown in Fig. 1, the printing device 1 includes a housing 8, a platen 12, a transport mechanism 14, an operation unit 15, a display screen 16, and a discharger 40 shown in Fig. 2.

[0013] As shown in FIG. 1, the housing 8 has a substantially rectangular parallelepiped shape. As shown in FIGS. 2 and 3, the housing 8 has a frame 2 and a cover 3. The frame 2 is configured in a lattice pattern with multiple shafts extending in the front-rear, left-right, or up-down directions. The cover 3 is configured from multiple plate-like members fixed to the frame 2 so as to cover the outer periphery of the frame 2. A platen opening 13 is formed in the front of the cover 3 of the housing 8, approximately in the center in the left-right and up-down directions. As shown in FIGS. 1 and 2, the platen 12 is made of a plate-like member having a substantially rectangular planar shape. The upper surface of the platen 12 is a support surface 12A that supports the print medium. The support surface 12A has a rectangular shape.

[0014] The housing 8 also has a dispenser cover 8A. The dispenser cover 8A is located in the front part of the cover 3 and above the platen opening 13. The dispenser cover 8A is formed in the shape of a roughly rectangular parallelepiped box that is open at the bottom, and covers the dispenser 40.

[0015] As shown in Figures 1 and 2, the housing 8 houses seven ink tanks 10 each storing seven colors of ink. From the rear, the seven ink tanks 10 store white, magenta, cyan, yellow, black, green, and orange ink. The housing 8 also houses a cleaning liquid tank 11 that stores cleaning liquid. The cleaning liquid tank 11 is disposed in front of the seven ink tanks 10 and is aligned with the ink tanks 10 in the front-to-rear direction.

[0016] As shown in FIG. 1, the operation units 15 are provided at positions on either side of the platen support unit 37 (described below) which is located forward of the platen opening 13. The operation units 15 output information according to operations by an operator to a control unit (not shown). By operating the operation unit 15, the operator can input a print start command, etc. to the control unit to start printing by the printing device 1. The print start command includes print data. The print data includes image data of the image to be formed on the print medium. The display screen 16 is provided on the front surface of the cover 3, above and to the right of the platen opening 13. The display screen 16 displays various information. The display screen 16 is also composed of a touch panel and has operation buttons for supplying treatment liquid.

[0017] The transport mechanism 14 transports the platen 12, on which the printing medium is placed, between the inside and outside of the housing 8 through the platen opening 13. When the platen 12 is positioned in a printing transport region P3 indicated by a two-dot chain line inside the housing 8 shown in FIG. 2, ink is ejected from the head 30, which will be described later, to perform printing. When the platen 12 is positioned in a treatment liquid ejection region P4 shown in FIG. 2, treatment liquid is ejected from the ejector 40, and the treatment liquid is applied to the printing medium. The treatment liquid ejected from the ejector 40 is, for example, a pretreatment liquid that forms a base before printing.

[0018] 2 and 3, the transport mechanism 14 has a support base 36, a platen support portion 37, a pair of left and right rails 38, and a transmission member 39. As shown in FIGS. 2 and 3, the platen support portion 37 has a tray 37A and a support portion 37B.

[0019] 3, the support portion 37B extends vertically and supports the platen 12 from below. The lower end of the support portion 37B is fixed to the tray 37A, connecting the tray 37A and the platen 12.

[0020] As shown in Figure 2, the pair of left and right rails 38 extend in the front-to-rear direction and support the platen support portion 37 so that it can move in the front-to-rear direction. The pair of rails 38 are disposed on a support base 36 that is disposed below the platen support portion 37. The support base 36 also extends in the front-to-rear direction. The support base 36 and the pair of rails 38 extend from the rear to the front of the housing 8 and protrude outside the housing 8. A transmission member 39 connects the platen support portion 37 to a sub-scanning motor (not shown) and moves the platen support portion 37 in the front-to-rear direction, i.e., the sub-scanning direction, in response to the drive of the sub-scanning motor.

[0021] With the platen 12 positioned forward of the front surface of the housing 8, i.e., outside the housing 8, the operator places the print medium on the support surface 12A of the platen 12. The position of the platen 12 shown in FIG. 2 is the set position P1 where the platen 12 supports the print medium. The treatment liquid ejection region P4 described above is located midway along the transport path of the platen 12, and is an area where treatment liquid is ejected from the ejector 40, and is located below the ejector 40. Furthermore, before printing on the print medium, the platen 12 moves from the set position P1 to a pre-printing standby position P2, indicated by a two-dot chain line in FIG. 2. The pre-printing standby position P2 is located behind the treatment liquid ejection region P4 and the print transport region P3, at the rear end of the transport path of the platen 12. The print transport region P3 is an area in the transport path of the platen 12 that vertically overlaps with the main scanning direction movement path of the head 30, which will be described later. The movement path of the heads 30 in the main scanning direction is the path between the rear end of the white head 31A (described later), which is the rearmost head 30, and the front end of the color head 32D (described later), which is the frontmost head 30.

[0022] The internal structure of the printing device 1 will now be described. As shown in Fig. 2, the printing device 1 includes, inside a housing 8, two white heads 31A and 31B, four color heads 32A to 32D, and a movement mechanism 7. The movement mechanism 7 includes a guide shaft 20 and a carriage 6 fixed to a frame 2. As shown in Fig. 2, the guide shaft 20 is made up of a front shaft 21, a rear shaft 22, a left shaft 23, and a right shaft 24.

[0023] As shown in FIG. 2 , the front shaft 21 is disposed at the front end of the frame body 2 and extends in the left-right direction from the left end to the right end of the frame body 2. The rear shaft 22 is disposed at approximately the center of the frame body 2 in the front-rear direction and extends in the left-right direction from the left end to the right end of the frame body 2. The left shaft 23 is disposed at the left end of the frame body 2 and extends in the front-rear direction from the left end of the front shaft 21 to the left end of the rear shaft 22. The right shaft 24 is disposed at the right end of the frame body 2 and extends in the front-rear direction from the right end of the front shaft 21 to the right end of the rear shaft 22. The front shaft 21 and the rear shaft 22 support the carriage 6. The transport mechanism 14 is fixed to the frame body 2.

[0024] As shown in Fig. 2, the carriage 6 is supported by a front shaft 21 and a rear shaft 22 so as to be movable in the main scanning direction. The carriage 6 is plate-shaped and extends in the front-rear and left-right directions. The carriage 6 extends from the front shaft 21 to the rear shaft 22. As shown in Fig. 2, the carriage 6 is provided with white heads 31A and 31B and color heads 32A to 32D.

[0025] The white heads 31A, 31B and the color heads 32A to 32D each have the same structure and are rectangular parallelepiped-shaped in this embodiment. Hereinafter, when the white heads 31A, 31B and the color heads 32A to 32D are collectively referred to or when one of them is not specified, they will be referred to as "head 30." As shown in FIG. 2, the white heads 31A, 31B are located at the rear of the carriage 6. The white heads 31A, 31B are arranged offset from each other in the front and rear. The white heads 31A, 31B are connected to an ink tank 10 that stores white ink via piping (not shown), and white ink is supplied from the ink tank 10.

[0026] As shown in FIG. 2, the color heads 32A and 32B are positioned in front of the white heads 31A and 31B. The color heads 32A and 32B are also positioned with a front-to-back offset, similar to the white heads 31A and 31B. The color heads 32C and 32D are positioned in front of the color heads 32A and 32B, as shown in FIG. 2. The color heads 32C and 32D are also positioned with a front-to-back offset, similar to the color heads 32A and 32B. The color heads 32A to 32D are each connected to six ink tanks 10 that store color ink via piping (not shown), and color ink is supplied from these ink tanks 10.

[0027] Each of these heads 30 has a plurality of nozzles formed on its underside, the nozzle surface 30A. The white heads 31A and 31B eject white ink downward from their plurality of nozzles. The plurality of nozzles in each of the color heads 32A to 32D are arranged so that six nozzle rows extending in the front-to-rear direction are aligned in the left-to-right direction. Each of the six nozzle rows in each of the color heads 32A to 32D corresponds to a different color ink. In other words, each of the color heads 32A to 32D ejects color ink of the color corresponding to its respective nozzle row downward from its plurality of nozzles.

[0028] Alternatively, each of the color heads 32A to 32D may have four nozzle rows, and the four nozzle rows of each of the color heads 32A to 32D may eject magenta, cyan, yellow, and black inks, but not green and orange inks. In this case, there may be no need to provide ink tanks 10 for storing green and orange inks.

[0029] The movement mechanism 7 also has a drive belt 7A and a main scanning motor 7M. The drive belt 7A is connected to the rear end of the carriage 6. The drive belt 7A is mounted on the rear shaft 22 and extends in the left-right direction. The left end of the drive belt 7A is connected to the main scanning motor 7M. When the main scanning motor 7M is driven, the drive belt 7A moves the carriage 6 in the left-right direction along the front shaft 21 and the rear shaft 22. In other words, the movement mechanism 7 moves the carriage 6, on which the head 30 is mounted, in the main scanning direction. Figure 2 shows the carriage 6 positioned at the right end of its movement range R.

[0030] The head 30 is positioned primarily at one of the cap position B1, the ejection region B2, and the head standby position B3 as the carriage 6 moves. The cap position B1 is the position of the head 30 when the carriage 6 is positioned at the left end of the movement range R. The cap position B1 is the position when the nozzle surface 30A of the head 30 is covered with a cap 51 (described later). The ejection region B2 is an area between the cap position B1 and the head standby position B3 in the main scanning direction, and is an area in the movement path of the head 30 that vertically overlaps with the print transport region P3, which is the transport path of the platen 12. Furthermore, when printing on a print medium, as the head 30 passes through the ejection region B2 as the carriage 6 moves, the head 30 ejects ink from the nozzles formed in the nozzle surface 30A based on print data, and printing is performed on the print medium on the platen 12. The head standby position B3 is the position of the head 30 when the carriage 6 is positioned at the right end of the movement range R. The head standby position B3 is a position where the head 30 is placed when an operator performs work on the head 30, such as cleaning.

[0031] The printing device 1 moves the platen 12 in the sub-scanning direction in the printing transport area P3 and moves the carriage 6 in the main scanning direction in the ejection area B2, thereby moving the printing medium relative to the head 30 in the sub-scanning direction and the main scanning direction.

[0032] The operation of moving the head 30 in the main scanning direction and discharging ink onto the printing medium when the head 30 faces the printing medium is called an "ejection scan." The printing device 1 prints on the printing medium by repeating ejection scans and moving the platen 12 in the sub-scanning direction. For example, during an ejection scan, the printing device 1 ejects white ink from the white heads 31A and 31B to form a base of color inks on the printing medium. During an ejection scan, the printing device 1 ejects color inks from the color heads 32A to 32D onto the base formed on the printing medium, thereby printing a color image.

[0033] 1, the housing 8 has a protrusion 8B that protrudes forward. The protrusion 8B is located in the front portion of the cover 3, below the platen opening 13. As shown in FIG. 3, the protrusion 3B has a door 8B1 on the front surface. The door 8B1 is configured to be openable and closable by two hinges 8B2, and when the door 8B1 is open, a processing liquid tank (not shown) that stores the processing liquid is exposed.

[0034] 2, the printing device 1 also includes a maintenance unit 50. The maintenance unit 50 includes six caps 51, a cleaning liquid tank 52, and six wiper units 53.

[0035] As shown in FIG. 2 , six caps 51 are provided for each of the six heads 30. The six caps 51 are positioned below the six heads 30 and vertically overlap the six heads 30 positioned at cap position B1. The six caps 51 can be raised and lowered by a lifting mechanism (not shown). For example, when moving the heads 30 to cap position B1, the lifting mechanism contacts the carriage 6 just before the heads 30 reach cap position B1. The lifting mechanism then raises the six caps 51 by utilizing the force exerted by the carriage 6 as it moves leftward until the heads 30 reach cap position B1. When the heads 30 reach cap position B1, the nozzle surface 30A of each head 30 is covered with the corresponding cap 51. On the other hand, when the carriage 6 is moved rightward from a state in which the nozzle surface 30A of each head 30 is covered with the corresponding cap 51, the caps 51 are lowered by the lifting mechanism. Alternatively, the lifting mechanism may be connected to a motor and may be driven by the motor to lift and lower the cap 51 .

[0036] 1, the cleaning liquid tank 52 is located between the cap position B1 and the discharge area B2 in the main scanning direction. When the carriage 6 moves to move the head 30 between the cap position B1 and the discharge area B2, the head 30 passes above the cleaning liquid tank 52.

[0037] As shown in FIGS. 4 to 11, the cleaning liquid tank 52 has a housing 61 and lids 62 and 63. The housing 61 is a substantially rectangular parallelepiped member extending in the front-to-rear direction. Inside the housing 61, cleaning liquid chambers 64 and 65, each having an open top, are provided. Cleaning liquid is stored in the cleaning liquid chambers 64 and 65. Alternatively, as will be described later, the cleaning liquid flows in the cleaning liquid chambers 64 and 65 as the cleaning liquid is supplied and discharged.

[0038] The cleaning liquid chamber 64 has a wiper area 71, a first drain area 72, and a second drain area 73. The wiper area 71 is the area on the left side of the cleaning liquid chamber 64. A supply port 74 is provided in the portion of the bottom surface 64A of the cleaning liquid chamber 64 that forms the wiper area 71. The supply port 74 is connected to the cleaning liquid tank 11 via piping (not shown), and the cleaning liquid is supplied from the supply port 74 to the wiper area 71.

[0039] The wiper region 71 also has two wiper support portions 71A and 71B. Each of the wiper support portions 71A and 71B supports a holding member 84 so that the holding member 84 can rotate about a rotation axis 84A that is parallel to the sub-scanning direction. A gear 86A is provided at the front end of each holding member 84. The gear 86A is connected to a wiper motor 85 via multiple gears, including a gear 86B that meshes with the gear 86A. By driving the wiper motor 85, the holding member 84 can be rotated about the rotation axis 84A.

[0040] Each holding member 84 holds the wiper unit 53. As a result, when the holding member 84 is rotated around the rotation shaft 84A, the wiper unit 53 rotates integrally with the holding member 84 around the rotation shaft 84A.

[0041] The two wiper units 53 held by the holding members 84 supported by the two wiper support portions 71A, 71B are arranged with a gap in the left-right direction. Furthermore, the positions of these two wiper units 53 in the front-to-rear direction are the same as those of the white heads 31A, 31B, and, like the white heads 31A, 31B, they are arranged with a shift in the front-to-rear direction. Here, six wiper units 53 are provided individually for the six heads 30. The two wiper units 53 held by the two holding members 84 supported by the wiper support portions 71A, 71B correspond to the two white heads 31A, 31B.

[0042] As shown in FIGS. 6, 11(a), and 11(b), the wiper unit 53 includes a first wiper 81, a second wiper 82, and a wiper support member 83. The first wiper 81 and the second wiper 82 extend in the front-rear direction over the entire length of the corresponding white heads 31A and 31B. The first wiper 81 and the second wiper 82 are spaced apart in the main scanning direction. The first wiper 81 is made of foam capable of absorbing liquid. The second wiper 82 is made of a rubber material or the like. The wiper support member 83 extends in the front-rear direction, supports the first wiper 81 and the second wiper 82, and is fixed to a holding member 84.

[0043] The wiper unit 53 can be moved between a wiping position shown in FIG. 11(a) and a submerged position shown in FIG. 11(b) by rotating the wiper unit 53 about the rotation shaft 84A. When the wiper unit 53 is in the wiping position, the leading ends of the first wiper 81 and the second wiper 82 are positioned above the nozzle surface 30A, as shown in FIG. 11(a). When the wiper unit 53 is in the submerged position, the leading ends of the first wiper 81 and the second wiper 82 are submerged in the cleaning liquid in the wiping region 71, as shown in FIG. 11(b). When the wiper unit 53 is in the submerged position, the entire wiper unit 53 is positioned below the nozzle surface 30A. Therefore, when the wiper unit 53 is in the immersion position, even if the head 30 is moved in the main scanning direction and passes above the wiper unit 53, the wiper unit 53 does not come into contact with the nozzle surface 30A.

[0044] In this embodiment, the nozzle surfaces 30A of the white heads 31A and 31B can be wiped by the first wiper 81 and the second wiper 82 of the two wiper units 53 supported by the wiper support portions 71A and 71B, respectively. To explain in more detail, first, with the wiper unit 53 positioned in the immersion position, the carriage 6 is moved to move the head 30 to the cap position B1. At this time, the cleaning liquid in the wiper area 71 is absorbed by the tip of the first wiper 81.

[0045] Next, the two wiper units 53 are rotated to the wiping position, and then the carriage 6 is moved to move the head 30 from the cap position B1 to the ejection area B2. As a result, the nozzle surfaces 30A of the white heads 31A and 31B are wiped by the first wipers 81 of the two wiper units 53, and then wiped by the second wipers 82 of the two wiper units 53. At this time, the first wipers 81 wipe the nozzle surface 30A while still absorbing the cleaning liquid. As a result, the cleaning liquid adheres to the nozzle surface 30A. Furthermore, the second wiper 82 wipes off the cleaning liquid that has adhered to the nozzle surface 30A during wiping by the first wiper 81, and smooths the ink meniscus inside the nozzles of the nozzle surface 30A.

[0046] As shown in Figures 5, 7, and 9, the first drain area 72 is located to the right of the wiper area 71. A first drain outlet 75 is provided in the portion of the bottom surface 64A of the cleaning liquid chamber 64 that forms the first drain area 72. The first drain outlet 75 is circular and has a diameter D1. The first drain outlet 75 is connected to a waste liquid section (not shown) via a flow path such as a tube.

[0047] The housing 61 is also provided with a wall portion 76 that protrudes upward from the bottom surface 64A of the cleaning liquid chamber 64 and surrounds the first drainage port area 72. As a result, the cleaning liquid chamber 64 is separated from the wiper area 71 and the first drainage port area 72 by the wall portion 76. The wall portion 76 also has a low-protruding portion 76A that protrudes less from the bottom surface 64A of the cleaning liquid chamber 64 than other parts of the wall portion 76. When the liquid level of the cleaning liquid supplied from the supply port 74 to the wiper area 71 reaches the upper end of the low-protruding portion 76A, the cleaning liquid flows from the wiper area 71 to the first drainage port area 72. The cleaning liquid that has flowed from the wiper area 71 into the first drainage port area 72 is discharged from the first drainage port 75.

[0048] An ink receiving plate 77 is disposed at the upper end of the first liquid drainage port area 72. The ink receiving plate 77 is a rectangular plate-shaped member with multiple through-holes 77A. A box-shaped flushing box 78 is formed in the first liquid drainage port area 72 by the portion of the housing 61 that forms the first liquid drainage port area 72, a wall portion 76, and the ink receiving plate 77. This flushing box 78 is common to the two white heads 31A and 31B and extends across the white heads 31A and 31B in the front-to-rear direction. Flushing can be performed by ejecting ink from the nozzles of the white heads 31A and 31B toward the ink receiving plate 77 while the white heads 31A and 31B are positioned above the ink receiving plate 77. The white ink ejected onto the ink receiving plate 77 during flushing flows into the first liquid drainage port area 72, i.e., into the flushing box 78, through the multiple through-holes 77A of the ink receiving plate 77. The white ink that has flowed into the first drainage port area 72 is discharged from the first drainage port 75 .

[0049] The second drain area 73 is located rearward of the first drain area 72. As a result, the second drain area 73 is spaced to the right and rearward of the wiper area 71. The wall 76 surrounding the first drain area 72 separates the first drain area 72 from the second drain area 73. A second drain outlet 79 is provided in the portion of the bottom surface 64A of the cleaning liquid chamber 64 that forms the second drain area 73. The second drain outlet 79 is circular and has a diameter D2. The diameter D2 of the second drain outlet 79 is equal to or greater than the diameter D1 of the first drain outlet 75. As a result, the opening area of ​​the second drain outlet 79 is equal to or greater than the opening area of ​​the first drain outlet 75. The second drain outlet 79 is connected to a waste liquid section (not shown) via a flow path such as a tube. 7 and 10, the bottom surface 64A of the cleaning liquid chamber 64 is inclined downward from the portion forming the wiper region 71 toward the second drainage port region 73. As a result, the bottom surface 64A of the cleaning liquid chamber 64 is located lower than the wiper region 71 in the second drainage port region 73.

[0050] As shown in FIGS. 5, 9, and 10, the second drainage port 79 is blocked by the plug 80 during printing or other operations. However, the plug 80 can be removed from the second drainage port 79, for example, when cleaning the cleaning liquid chamber 64. Specifically, the plug 80 is a generally cylindrical member made of a rubber material or other material. The lower end of the plug 80 is tapered so that the diameter gradually decreases toward the bottom. The tapered lower end of the plug 80 is inserted into the second drainage port 79, thereby blocking the second drainage port 79. With the lid 62 positioned in the open position (described later), the plug 80 can be removed from the second drainage port 79 by pulling the plug 80 upward, with its lower end inserted into the second drainage port 79. A generally cylindrical protrusion 80A protruding upward is provided at the center of the top surface of the plug 80. The portion of the upper surface of plug 80 that surrounds protrusion 80A is a flat surface portion 80B.

[0051] As shown in Figures 4 and 8, the cleaning liquid chamber 65 is located in front of the cleaning liquid chamber 64. The cleaning liquid chamber 64 and the cleaning liquid chamber 65 are separated from each other. The cleaning liquid chamber 65 is provided with a supply port (not shown) connected to the cleaning liquid tank 11 via piping (not shown), and the cleaning liquid is supplied to the cleaning liquid chamber 65 from this supply port. The cleaning liquid chamber 65 is also provided with a drain port (not shown), and the cleaning liquid inside the cleaning liquid chamber 65 is discharged from this drain port. The drain port is also connected to a waste liquid section (not shown) via a flow path such as a tube.

[0052] Furthermore, a pump may be provided in the middle of a flow path connecting the first drain port 75 and second drain port 79 of the cleaning liquid chamber 64, and the drain ports provided in the cleaning liquid chamber 65, to the waste liquid section. By driving this pump, the cleaning liquid, foreign matter, etc. in the cleaning liquid chambers 64, 65 may be sucked out through these drain ports.

[0053] The cleaning liquid chamber 65 is also provided with four wiper support portions that rotatably support four holding members 84 to which four of the six wiper units 53, corresponding to the four color heads 32A to 32D, are attached. The four holding members 84 supported by these four wiper support portions are also connected to the wiper motor 85 via gears (not shown). When the wiper motor 85 is driven, the four holding members 84 supported by these four wiper support portions and the four wiper units 53 attached to these four holding members 84 rotate. This allows the four wiper units 53 to be positioned at the wiping position and the immersion position described above. Furthermore, as described above, when the nozzle surfaces 30A of the white heads 31A and 31B are wiped by the first wipers 81 and second wipers 82 of the two wiper units 53 corresponding to the white heads 31A and 31B, the nozzle surfaces 30A of the color heads 32A to 32D may be wiped by the first wipers 81 and second wipers 82 of the four wiper units 53 corresponding to the color heads 32A to 32D.

[0054] The cleaning liquid chamber 65 is also provided with an ink receiving plate 87 corresponding to the color heads 32A and 32B, and an ink receiving plate 88 corresponding to the color heads 32C and 32D. The ink receiving plates 87 and 88 are similar to the ink receiving plate 77. This allows flushing to be performed by ejecting ink from the nozzles of the color heads 32A and 32B toward the ink receiving plate 87 while the color heads 32A and 32B are positioned above the ink receiving plate 87. Furthermore, when the color heads 32C and 32D are positioned above the ink receiving plate 88, flushing to be performed by ejecting ink from the nozzles of the color heads 32C and 32D toward the ink receiving plate 88.

[0055] The lid 62 is disposed above the portion of the housing 61 that forms the cleaning liquid chamber 64. The lid 62 is configured to be openable and closable by two hinges 62A, and is movable between a closed position in which the opening at the top end of the cleaning liquid chamber 64 is closed, as shown in FIG. 4, and an open position in which the opening at the top end of the cleaning liquid chamber 64 is open, as shown in FIGS. 5 and 7. In addition, the lid 62 is fixed to the housing 61 by two screws 69A and 69B when it is in the closed position, as shown in FIG. 4. When the two screws 69A and 69B are removed, the lid 62 becomes movable between the closed position and the open position.

[0056] The lid 62 also has two substantially rectangular through-holes 62B formed therein that correspond to the two wiper units 53. When the lid 62 is in the closed position, the two wiper units 53 are exposed through the two through-holes 62B. The lid 62 also has a substantially rectangular through-hole 62C formed therein that corresponds to the ink receiving plate 77. When the lid 62 is in the closed position, the ink receiving plate 77 is exposed through the two through-holes 62C.

[0057] The lid 62 also has a circular through-hole 62D formed therein that corresponds to the protrusion 80A of the plug 80. When the lid 62 is in the closed position, the protrusion 80A of the plug 80 fits into the through-hole 62D. When the lid 62 is in the closed position, the portion of the lid 62 that surrounds the through-hole 62D comes into contact with the surface 80B of the plug 80 from above. This allows the lid 62 to press the plug 80 from above, making it difficult for the plug 80 to come out of the second drainage port 79. In this embodiment, the surface 80B is flat, but this is not limiting. The surface 80B may have an uneven surface, as long as the portion of the lid 62 that surrounds the through-hole 62D can come into contact with the surface 80B and press the plug 80 from above.

[0058] Here, white ink is prone to solidification due to differences in composition with color inks, and solidified white ink is likely to adhere to the nozzle surfaces 30A of the white heads 31A and 31B. As described above, when the wiper unit 53 wipes the nozzle surfaces 30A of the white heads 31A and 31B, solidified white ink may adhere to the first wiper 81 or the second wiper 82. Therefore, when the wiper unit 53 is subsequently moved to the immersion position, solidified white ink may flow from the first wiper 81 or the second wiper 82 into the wiper area 71, resulting in accumulation of solidified white ink in the cleaning liquid chamber 64. In this embodiment, an operator moves the lid 62 from the closed position to the open position and then removes the plug 80 from the second drain outlet 79. This allows the operator to discharge solid matter, such as solidified white ink, that has accumulated in the cleaning liquid chamber 64, along with the cleaning liquid in the cleaning liquid chamber 64 through the second drain outlet 79. In other words, the cleaning liquid chamber 64 can be cleaned.

[0059] Furthermore, after cleaning the cleaning liquid chamber 64, the worker attaches the plug 80 to the second drainage port 79 by inserting the lower end of the plug 80 into the second drainage port 79, and then moves the lid 62 from the open position to the closed position. At this time, the protruding portion 80A of the plug 80 fits into the through-hole 62D, so that the wall surface of the through-hole 62D comes into contact with the outer peripheral surface of the protruding portion 80A, and the plug 80 is positioned with respect to the second drainage port 79. Therefore, even if the plug 80 is slightly tilted or otherwise misaligned when the worker inserts the lower end of the plug 80 into the second drainage port 79, the plug 80 is positioned with respect to the second drainage port 79. In this embodiment, the wall surface of the through-hole 62D corresponds to the "positioning portion" of the present invention.

[0060] The lid 63 is disposed in a portion of the housing 61 that forms the cleaning liquid chamber 65, and closes the opening at the top end of the cleaning liquid chamber 65. The lid 63 is fixed to the housing 61 with screws or the like. The lid 63 also has four substantially rectangular through-holes 63A formed therein that correspond to the four wiper units 53. The through-holes 63A are similar to the through-holes 62B. The four wiper units 53 provided in the cleaning liquid chamber 65 are exposed through the four through-holes 63A.

[0061] The lid 63 is also formed with two substantially rectangular through-holes 63B corresponding to the two ink receiving plates 87, 88. The through-holes 63B are similar to the through-hole 62C. The two ink receiving plates 87, 88 provided in the cleaning liquid chamber 65 are exposed through the two through-holes 63B.

[0062] <Effects> In this embodiment, as described above, when the nozzle surface 30A is wiped with the first wiper 81 and the second wiper 82, solidified white ink and other solid matter adhering to the nozzle surface 30A may adhere to the first wiper 81 or the second wiper 82. If the wiper unit 53 is rotated to the immersion position in this state, the solid matter adhering to the first wiper 81 or the second wiper 82 may flow into the wiper region 71 and accumulate in the wiper region 71. In this embodiment, a wall 76 is provided in the cleaning liquid chamber 64, and the wiper region 71 and the first drainage port region 72 are separated by the wall 76. Therefore, the cleaning liquid in the cleaning liquid chamber 64 flows over the low-protrusion portion 76A of the wall 76 and flows from the wiper region 71 to the first drainage port region 72, but solid matter such as solidified white ink is less likely to flow from the wiper region 71 to the first drainage port region 72. This makes it difficult for solid matter to clog the first drain outlet 75 and the flow path connected to the first drain outlet 75. Furthermore, by removing the plug 80 from the second drain outlet 79 and cleaning the cleaning liquid chamber 64, solid matter such as solidified white ink can be discharged together with the cleaning liquid from the second drain outlet 79, which is provided separately from the first drain outlet 75. This makes it easy to clean the cleaning liquid chamber 64.

[0063] In this embodiment, the second drain port 79 is provided in the second drain port area 73, which is separated from the wiper area 71. This makes it less likely that the plug 80 will interfere with the wiper unit 53, making it easy to remove the plug 80 from the second drain port 79 during cleaning and to attach the plug 80 to the second drain port 79 after cleaning.

[0064] In addition, in this embodiment, the bottom surface 64A of the cleaning liquid chamber 64 is inclined downward from the wiper region 71 toward the second drainage port region 73, so that the bottom surface 64A of the cleaning liquid chamber 64 is located lower in the second drainage port region 73 than the wiper region 71. This makes it easier for the cleaning liquid to flow from the wiper region 71 to the second drainage port region 73 during cleaning, making it easier to clean the cleaning liquid chamber 64.

[0065] Furthermore, in this embodiment, a flushing box 78 is provided in the first drainage port area 72. This allows the ink discharged into the flushing box 78 to be efficiently discharged from the first drainage port.

[0066] Furthermore, in this embodiment, since the opening area of ​​the second drainage outlet 79 is equal to or larger than the opening area of ​​the first drainage outlet 75, when cleaning the cleaning liquid chamber 64, cleaning liquid, solidified white ink, etc. can be efficiently discharged from the second drainage outlet 79, which has an opening area equal to or larger than that of the first drainage outlet 75.

[0067] Furthermore, in this embodiment, as described above, when the lid 62 is moved from the open position to the closed position with the plug 80 attached to the second drainage port 79, the wall surface of the through-hole 62D comes into contact with the protruding portion 80A of the plug 80, thereby positioning the plug 80 at the second drainage port 79. This makes it possible to more reliably close the second drainage port 79 with the plug 80. Furthermore, when the lid 62 is in the closed position, the portion of the lid 62 surrounding the through-hole 62D comes into contact from above with the surface portion 80B surrounding the protruding portion 80A on the upper surface of the plug 80, so that the plug 80 is pressed down from above by the lid 62, making it difficult for the plug 80 to come out of the second drainage port 79.

[0068] <Modification> Although the preferred embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications are possible within the scope of the claims.

[0069] For example, in the above embodiment, when the lid 62 is in the closed position, the lid 62 contacts the plug 80 from above. However, this is not limited to this. When the lid 62 is in the closed position, the lid 62 does not have to contact the plug 80 from above. Furthermore, when the lid 62 is moved from the open position to the closed position, the positioning portion that comes into contact with the protruding portion 80A of the plug 80 to position the plug 80 with respect to the second drainage port 79 is not limited to being formed by a through-hole. A notch may be formed in the lid 62 instead of the through-hole 62D. Then, when the lid 62 is moved from the open position to the closed position, the wall surface of the notch may come into contact with the protruding portion 80A of the plug 80 to position the plug 80 with respect to the second drainage port 79. In this case, the wall surface of the notch corresponds to the "positioning portion" of the present invention.

[0070] Furthermore, the positioning portion that positions the plug 80 relative to the second drainage port 79 may be, for example, an edge of the lid 62 or another portion separate from the through-hole and notch formed in the lid 62. Furthermore, the portion of the plug 80 that comes into contact with the positioning portion of the lid 62 may be a portion separate from the protruding portion that protrudes upward. Furthermore, the lid 62 does not have to have a positioning portion that comes into contact with the plug 80 and positions the plug 80 relative to the second drainage port 79 when the lid 62 is moved from the open position to the closed position.

[0071] In the above-described embodiment, both the first drainage outlet 75 and the second drainage outlet 79 are circular, and the diameter D2 of the second drainage outlet 79 is equal to or larger than the diameter D1 of the first drainage outlet 75, so that the opening area of ​​the second drainage outlet 79 is equal to or larger than the opening area of ​​the first drainage outlet 75. However, this is not limited to this. For example, at least one of the first drainage outlet 75 and the second drainage outlet 79 may have a shape other than circular, and the opening area of ​​the second drainage outlet 79 may be equal to or larger than the opening area of ​​the first drainage outlet 75. Furthermore, the opening area of ​​the second drainage outlet 79 may be smaller than the opening area of ​​the first drainage outlet 75.

[0072] In addition, in the above-described embodiment, the flushing box 78 is provided in the first drainage port area 72, but this is not limiting. The flushing box 78 may be provided in an area of ​​the cleaning liquid chamber 64 separate from the first drainage port area 72. Alternatively, the flushing box 78 may not be provided in the cleaning liquid chamber 64.

[0073] In the above-described embodiment, the bottom surface 64A of the cleaning liquid chamber 64 is inclined downward from the wiper region 71 toward the second drainage outlet region 73, so that the bottom surface 64A of the cleaning liquid chamber 64 is located lower than the wiper region 71 in the second drainage outlet region 73. However, this is not limited to this. For example, a step may be provided in the bottom surface 64A of the cleaning liquid chamber 64 between the wiper region 71 and the second drainage outlet region 73, so that the bottom surface 64A of the cleaning liquid chamber 64 is located lower than the wiper region 71 in the second drainage outlet region 73. Alternatively, the wiper region 71 and the second drainage outlet region 73 may be located at the same height as the bottom surface 64A of the cleaning liquid chamber 64. Alternatively, the bottom surface 64A of the cleaning liquid chamber 64 may be located higher than the wiper region 71 in the second drainage outlet region 73.

[0074] In the above embodiment, the second drain outlet 79 is provided in the second drain outlet area 73 of the cleaning liquid chamber 64, which is away from the wiper area 71, but this is not limiting. For example, the second drain outlet may be provided in another area of ​​the cleaning liquid chamber 64, such as the wiper area 71 or the first drain outlet area 72.

[0075] In the above example, the first drain outlet and the second drain outlet are provided on the bottom surface 64A of the cleaning liquid chamber 64, but this is not limiting. At least one of the first drain outlet and the second drain outlet may be provided in another part of the cleaning liquid chamber 64, for example, in a lower part of the side wall surface of the cleaning liquid chamber 64.

[0076] The cleaning liquid chamber 65 may also be provided with a wall separating the area where the wiper is disposed from the area where the drain port is provided, similar to the wall 76 in the above embodiment. The cleaning liquid chamber 65 may also be provided with another drain port blocked by a removable plug, similar to the second drain port 79 in the above embodiment.

[0077] Although the above description has been given of an example in which the present invention is applied to a printing device that ejects ink to print on a print medium, the present invention is not limited to this. For example, the present invention may be applied to a liquid ejection device other than a printing device that ejects a liquid other than ink, such as a liquid resin or metal liquid, onto a receiving medium. [Explanation of symbols]

[0078] 1 Printing device 30A nozzle surface 52 Cleaning solution tank 53 Wiper unit 64 Cleaning fluid room 64A bottom 71 Wiper area 72 First drainage area 73 Second drainage area 75 First drain outlet 78 Flushing Box 79 Second drain outlet 80 stopper 80A protrusion 80B surface part 81 First wiper 82 Second wiper

Claims

1. A nozzle surface; a cleaning liquid tank for storing a cleaning liquid or through which the cleaning liquid flows; a wiper that is displaceable between an immersion position where the wiper is immersed in the cleaning liquid in the cleaning liquid tank and a wiping position where the wiper can come into contact with the nozzle surface, and that wipes the nozzle surface when positioned at the wiping position; a first drain port provided in the cleaning liquid tank for discharging the cleaning liquid in the cleaning liquid tank; a wall portion provided in a portion of the cleaning liquid tank between a wiper region including a portion overlapping with the wiper in a vertical direction and a first drainage port region including a portion where the first drainage port is provided, the wall portion protruding upward from a bottom surface of the cleaning liquid tank and separating the wiper region from the first drainage port region; a second drain port provided in the cleaning liquid tank separately from the first drain port, for discharging the cleaning liquid in the cleaning liquid tank; a plug that is removably attached to the second drainage port and closes the second drainage port.

2. 2. The liquid ejection device according to claim 1, wherein the second drain port is provided in a second drain port area of ​​the cleaning liquid tank that is separated from the wiper area.

3. The second drain is provided on a bottom surface of the second drain area, 3. The liquid ejection device according to claim 2, wherein the bottom surface of the cleaning liquid tank is located lower than the wiper area in the second drain port area.

4. 2. The liquid ejection device according to claim 1, wherein a flushing box that receives the liquid ejected from the nozzle surface is provided in the first liquid drainage port area.

5. 2. The liquid ejection device according to claim 1, wherein the opening area of ​​the second drainage port is equal to or larger than the opening area of ​​the first drainage port.

6. a cover provided on the cleaning liquid tank and movable between a closed position that closes the upper end of the cleaning liquid tank and an open position that opens the upper end of the cleaning liquid tank; The liquid ejection device according to claim 1 , wherein the lid has a positioning portion that contacts the plug when the lid moves from the open position to the closed position, thereby positioning the plug relative to the second drain port.

7. the second drain port is provided on the bottom surface of the cleaning liquid tank, The plug has a protrusion protruding upward from an upper surface of the plug, The upper surface of the plug has a surface portion surrounding the protrusion, the positioning portion is formed by a hole or a notch into which the protrusion fits when the lid is in the closed position, The liquid ejection device according to claim 6, wherein a portion of the lid surrounding the hole or notch contacts the surface portion from above when the lid is in the closed position.

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