JP2015193198A - Liquid discharge device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate the need for a driving source for supplying a liquid from a main tank to a plurality of sub-tanks, and realize downsizing.SOLUTION: At the start of initial introduction (ink supply from a main tank 71 to empty sub-tanks 61a to 61d), since a main space 72 communicates with ambient air through air flow channels 91a to 91d, ink inside the main space 72 flows out from a main outlet port 75 by its own weight and flows into each of sub-spaces 62a to 62d sequentially. When the liquid level of the ink inside the sub-space 62d reaches the height of an opening 66d, the opening 66d is blocked by the ink, the supply of the air from the sub-space 62d to the main space 72 through the air flow channel 91d is stopped, and thereby the ink inside the main space 72 no longer flows out from the main outlet port 75. That is, the ink supply from the main tank 71 to the sub-tanks 61a to 61d is stopped.

Description

  The present invention relates to a liquid ejection apparatus including a plurality of heads.

  A liquid ejection apparatus including a plurality of heads is known. For example, Patent Document 1 discloses an ink jet printer 1 (liquid ejecting apparatus) including four heads 2. The printer 1 further includes a main tank 32 (main tank) and four level tanks 31 (sub tanks) provided in correspondence with each of the four heads 2. Each head 2 is connected to a corresponding level tank 31 through an ink supply pipe 41, and discharges ink supplied from the corresponding level tank 31 from an ejection port. According to Patent Document 1, by driving the pump 8, the ink in the main tank 32 is supplied to the uppermost level tank 31 via the ink supply path 7, and further, the ink is sequentially supplied to the lower level tank 31. The Excess ink that has overflowed in the lowest level tank 31 is collected in the main tank 32.

JP 2002-67350 A (refer to FIG. 1 and paragraphs 0033 to 0036 in particular)

  According to Patent Document 1, a pump 8 (drive source) is required to supply liquid from a main tank to a plurality of sub tanks. Therefore, it is impossible to reduce the size of the apparatus.

  An object of the present invention is to provide a liquid ejection apparatus that does not require a drive source for supplying liquid from a main tank to a plurality of sub tanks and can be miniaturized.

  A liquid ejection apparatus according to a first aspect of the present invention includes a first head having a plurality of first ejection ports for ejecting a liquid, and a second head having a plurality of second ejection ports for ejecting a liquid. A mounting portion to which a main tank having a main space for storing a head and a liquid is mounted, the main opening communicating with the main space when the main tank is mounted, and more than the main opening A mounting portion having a main outlet that communicates with the main space when the main tank is mounted, an upstream subspace for storing liquid, and the upstream subspace and the atmosphere communicate with each other. An upstream sub-tank configured to supply the first head with the liquid stored in the upstream sub-space, and from the main outlet, the same as the main outlet. Located at a height or below the main outlet and in front A first liquid flow path extending to an upstream inlet communicating with the upstream subspace and configured to supply liquid from the main space to the upstream subspace; a downstream subspace for storing liquid; And a downstream sub-tank having a downstream atmosphere communication port for communicating the downstream sub-space with the atmosphere, and configured to supply liquid stored in the downstream sub-space to the second head. From the upstream outlet located at the same height as the main outlet or below the main outlet and communicating with the upstream subspace, the same height as the upstream outlet or below the upstream outlet and the downstream A second liquid flow path that extends to a downstream inlet that communicates with the subspace and is configured to supply liquid from the upstream subspace to the downstream subspace; and is positioned below the upstream outlet; From a downstream opening communicating with the downstream subspace Extending to the main opening and communicating the main space with the atmosphere via the downstream opening and the main opening when the liquid level of the liquid in the downstream subspace is located below the downstream opening. And a first gas flow path configured as described above.

  A liquid ejection apparatus according to a second aspect of the present invention includes a first head having a plurality of first ejection ports for ejecting a liquid, and a second head having a plurality of second ejection ports for ejecting a liquid. A main tank having a main space for storing liquid, a main tank, an upstream subspace for storing liquid, and an upstream air communication port for communicating the upstream subspace with the atmosphere; An upstream sub tank configured to supply liquid stored in the upstream sub space to the first head, and a main outlet communicating with the main space, the same height as the main outlet or the main outlet A first liquid flow path that is located below and extends to an upstream inlet that communicates with the upstream subspace, and is configured to supply liquid from the main space to the upstream subspace; A downstream subspace for storage, and the downstream subspace A downstream sub-tank that has a downstream atmospheric communication port for communicating with the second sub-space, and is configured to supply the liquid stored in the downstream sub-space to the second head, and the same height as the main outlet Alternatively, from an upstream outlet located below the main outlet and communicating with the upstream subspace to a downstream inlet located at the same height as the upstream outlet or below the upstream outlet and communicating with the downstream subspace. A second liquid flow path that extends and is configured to supply liquid from the upstream subspace to the downstream subspace; and a downstream that is located below the upstream outlet and communicates with the downstream subspace When the liquid level of the liquid in the downstream subspace is located below the downstream opening, it extends from the opening to a main opening located above the main outlet and communicating with the main space. Through the opening and the main opening It is configured to communicate the space and the atmosphere, characterized by comprising a first gas flow path, the.

  According to the present invention, when the liquid level of the liquid in the downstream subspace is located below the downstream opening, the main space communicates with the atmosphere via the first gas flow path, and the gas is in the main space. Have been supplied. For this reason, the liquid stored in the main space flows out from the main outlet by its own weight. The liquid flowing out from the main outlet flows into the upstream subspace through the first liquid channel. Thereafter, the liquid level in the upstream subspace reaches the height of the upstream outlet. Thereafter, when the liquid further flows into the upstream subspace, the liquid in the upstream subspace flows out from the upstream outlet and flows into the downstream subspace via the second liquid channel. When the liquid level in the downstream subspace reaches the height of the downstream opening, the downstream opening is closed with the liquid. When the downstream opening is closed with the liquid, the communication between the main space and the atmosphere via the first gas flow path is blocked. Thereby, no gas is supplied to the main space via the first gas flow path, and the liquid in the main space does not flow out from the main outlet. That is, the liquid supply from the main tank to the plurality of sub tanks is stopped. Thus, according to the present invention, the liquid is supplied from the main tank to the plurality of sub tanks without driving the drive source. That is, according to the present invention, a drive source for supplying liquid from the main tank to the plurality of sub tanks is not necessary, and the apparatus can be downsized.

  The liquid ejection apparatus according to the present invention extends from the upstream opening located at the same height as the upstream outlet or below the upstream outlet and communicates with the upstream subspace to the main opening, and the upstream subspace. A second gas flow path configured to cause the main space and the atmosphere to communicate with each other via the upstream opening and the main opening when the liquid level of the liquid is located below the upstream opening. You may prepare. According to this configuration, when the amount of liquid in the upstream sub space decreases due to a liquid discharge operation or the like, liquid can be replenished to the upstream sub space. Specifically, when the liquid level of the liquid in the upstream subspace is positioned below the upstream opening, the main space communicates with the atmosphere via the second gas flow path, and gas is supplied to the main space. Along with this, the liquid is supplied from the main space to the upstream subspace via the first liquid flow path.

  The first gas channel and the second gas channel may have a common part. According to this configuration, the apparatus can be further reduced in size by sharing the gas flow path.

  The liquid ejection device according to the present invention is a first gas permeable film provided in the downstream opening, and is configured to close the downstream opening, allow gas to pass, and not allow liquid to pass. A permeable membrane, and a second gas permeable membrane provided in the upstream opening, wherein the second gas permeable membrane is configured to close the upstream opening and allow gas to pass but not liquid to pass through. Furthermore, you may prepare. In the absence of a gas permeable membrane, liquid can enter the gas flow path, such as when the device is tilted. When the first gas channel and the second gas channel have a common part, the liquid supplied into the upstream subspace enters the second gas channel and further the first gas channel from the upstream opening. obtain. In this case, both the gas supply to the main space via the first gas flow channel and the gas supply to the main space via the second gas flow channel are shut off, and a problem may occur in the liquid supply from the main tank. . On the other hand, according to the above configuration, by providing the first and second gas permeable membranes, the liquid can be prevented from entering the first and second gas flow paths, and the occurrence of liquid supply problems can be prevented. be able to.

  The first gas channel and the second gas channel may be configured such that the resistance of the first gas channel is smaller than the resistance of the second gas channel. When the resistance of the first gas flow path and the resistance of the second gas flow path are the same, the loss of liquid supply to the downstream sub tank is large, and the liquid supply speed to the downstream sub tank can be reduced. On the other hand, according to the said structure, the fall of the liquid supply speed to a downstream subtank can be suppressed.

  The liquid ejection apparatus according to the present invention includes a third head having a plurality of third ejection ports for ejecting liquid, an intermediate subspace for storing the liquid supplied from the main space, and the intermediate An intermediate subtank having an intermediate air communication port for communicating the subspace with the atmosphere, and configured to supply the liquid stored in the intermediate subspace to the third head; The second liquid flow path extends from the upstream outlet to an intermediate inlet located at the same height as the upstream outlet or below the upstream outlet and communicating with the intermediate subspace. An upstream flow path configured to supply liquid to the intermediate sub space, and an intermediate outlet located at the same height as the upstream outlet or below the upstream outlet and communicating with the intermediate sub space Extending to the downstream inlet, and During liquid to the downstream secondary space from the sub space is configured to be supplied may include a downstream flow path. According to this configuration, even when three or more heads are provided, liquid supply from the main tank to the plurality of sub tanks can be realized without driving the drive source.

  The first liquid channel may be configured such that the resistance of the downstream channel is smaller than the resistance of the upstream channel. According to this configuration, the downstream liquid flow path is configured to have a smaller resistance, thereby suppressing a decrease in the liquid supply rate to the downstream side sub-tanks and aligning the liquid supply rates to the plurality of sub-tanks. be able to.

  The liquid ejection device according to the present invention extends from the intermediate opening located at the same height as the intermediate outlet or below the intermediate outlet and communicating with the intermediate auxiliary space to the main opening, and the intermediate auxiliary space A third gas flow path configured to allow the main space and the atmosphere to communicate with each other through the intermediate opening and the main opening when the liquid level of the liquid inside is located below the intermediate opening; You may prepare. According to this configuration, when the amount of liquid in the intermediate sub space decreases due to a liquid discharge operation or the like, it is possible to replenish liquid in the intermediate sub space. Specifically, when the liquid level of the liquid in the intermediate subspace is positioned below the intermediate opening, the main space communicates with the atmosphere via the third gas flow path, and gas is supplied to the main space. Accordingly, liquid is supplied from the main space to the intermediate subspace via the upstream flow path.

  The first gas channel, the second gas channel, and the third gas channel may have a common portion. According to this configuration, the apparatus can be further reduced in size by sharing the gas flow path.

  The liquid ejection device according to the present invention is a first gas permeable film provided in the downstream opening, and is configured to close the downstream opening, allow gas to pass, and not allow liquid to pass. A permeable membrane, a second gas permeable membrane provided in the upstream opening, wherein the second gas permeable membrane is configured to close the upstream opening and allow gas to pass therethrough and liquid not to pass through; A third gas permeable membrane provided in the intermediate opening may further comprise a third gas permeable membrane configured to close the intermediate opening, allow gas to pass, and not allow liquid to pass. In the absence of a gas permeable membrane, liquid can enter the gas flow path, such as when the device is tilted. Further, when the first to third gas flow paths have a common portion, the liquid supplied in the upstream subspace enters the second gas flow path and further the first gas flow path from the upstream opening, The liquid supplied into the subspace may enter the third gas channel and further the first gas channel from the intermediate opening. In this case, all of the gas supply to the main space via the first to third gas flow paths is blocked, and a problem may occur in the liquid supply from the main tank. On the other hand, according to the said structure, by providing the 1st-3rd gas permeable film, the penetration | invasion of the liquid to a 1st-3rd gas flow path is prevented, and generation | occurrence | production of the malfunction of a liquid supply is prevented. be able to.

  The first gas channel, the second gas channel, and the third gas channel have a resistance of the third gas channel smaller than a resistance of the second gas channel, and the first gas The resistance of the flow path may be configured to be smaller than the resistance of the third gas flow path. According to this configuration, the gas flow path corresponding to the downstream side subtank is configured to have a smaller resistance, thereby suppressing a decrease in the liquid supply speed to the downstream side subtank, and to a plurality of subtanks. The liquid supply speed can be made uniform.

  The vertical distance from the bottom of the downstream subspace to the downstream opening may be greater than the vertical distance from the bottom of the upstream subspace to the upstream opening. The maximum water level in the downstream secondary tank is the same as the height of the downstream opening. According to the above configuration, a larger amount of liquid is allowed to flow in the downstream subspace than when the vertical distance from the bottom of the downstream subspace to the downstream opening is equal to or less than the vertical distance from the bottom of the upstream subspace to the upstream opening. Can be stored. That is, the volume of the downstream subspace can be used efficiently.

  The vertical distance from the bottom of the downstream subspace to the downstream opening may be equal to the vertical distance from the bottom of the upstream subspace to the upstream outlet. The maximum water level of the downstream secondary tank is the same as the height of the downstream opening, and the maximum water level of the upstream secondary tank is the same as the height of the upstream outlet. According to the above configuration, the height of the maximum water level with respect to the bottom of the sub space is equal in each of the upstream sub tank and the downstream sub tank, so the vertical position of the first head relative to the upstream sub tank and the second position relative to the downstream sub tank. The vertical position of the head can be set to be the same. That is, according to the above configuration, it is easy to set the positional relationship between each sub tank and the corresponding head.

  The liquid ejection device according to the present invention is configured to output a signal indicating a liquid level height of the liquid in the downstream subspace, the plurality of first ejection ports, and the plurality of second chambers. The liquid level in the downstream subspace reaches a predetermined water level based on a signal output from the forced discharge unit configured to forcibly discharge the liquid from the discharge port and the downstream sensor. And a controller that controls the forcible discharge unit to forcibly discharge the liquid from the plurality of first discharge ports and the plurality of second discharge ports when the determination is made. According to this configuration, at the time of initial introduction (liquid supply from the main tank to a plurality of sub-tanks in an empty state), forcible discharge is performed after liquid supply from the main tank to the plurality of sub-tanks is completed. Time can be shortened, and time loss can be reduced.

  The liquid ejection device according to the present invention is configured to output a signal indicating a liquid level height of the liquid in the downstream subspace, and a liquid level height of the liquid in the upstream subspace. And an upstream sensor configured to output the indicated signal. According to the said structure, since the structure of an upstream subtank and a downstream subtank is shared, manufacture is easy. In addition, based on the signal output from the upstream sensor and / or downstream sensor, the time during which the liquid level in the upstream subspace and / or downstream subspace has not reached the predetermined water level exceeds the predetermined time In addition, by restricting the liquid discharge operation from the head corresponding to the sub-tank or performing error notification, it is possible to avoid problems such as idling. In addition, it is possible to estimate the empty of the main tank based on the signals output from the upstream sensor and the downstream sensor without providing a sensor that outputs a signal indicating the liquid level of the liquid in the main tank. Therefore, it is not necessary to provide the main tank or the mounting part with a sensor that outputs a signal indicating the liquid level of the liquid in the main tank, and the configuration of the main tank or the mounting part can be simplified.

  The liquid ejection device according to the present invention is a valve provided in the mounting portion or the main tank, and the main space and the atmosphere are separated when a difference between the pressure of the main space and the pressure of the atmosphere is a predetermined value or less. A valve may be further provided that is configured to take a blocking position for blocking the communication, and to take a permission position for allowing the communication when the difference exceeds the predetermined value. When there is no valve, if the atmospheric pressure decreases and the pressure difference between the main space and the atmosphere increases, there may be a problem that the amount of liquid supplied from the main space becomes excessive. On the other hand, according to the above configuration, when the pressure difference exceeds a predetermined value, the valve switches from the blocking position to the permission position, and the communication between the main space and the atmosphere is blocked to the permitted state. Switch. Thereby, since the pressure in the main space can be released to the atmosphere, the pressure difference between the main space and the atmosphere is reduced, and the above problem can be reduced.

  The first liquid channel and the second liquid channel may be configured such that the resistance of the second liquid channel is smaller than the resistance of the first liquid channel. When the resistance of the first liquid flow path and the resistance of the second liquid flow path are the same, the loss of liquid supply to the downstream sub tank is large, and the liquid supply speed to the downstream sub tank can be reduced. On the other hand, according to the said structure, the fall of the liquid supply speed to a downstream subtank can be suppressed.

  The liquid ejection device according to the present invention is a main gas permeable film provided in the main opening, wherein the main gas permeable film is configured to close the main opening, allow gas to pass, and not allow liquid to pass. May be further provided. According to this configuration, it is possible to prevent liquid from entering the main space through the main opening.

  The upstream sub tank has an upstream supply port for communicating the upstream sub space and the plurality of first discharge ports, and the downstream sub tank includes the downstream sub space and the plurality of second discharge ports. May have a downstream supply port for communicating with each other.

  The upstream supply port may be positioned below the upstream outlet, and the downstream supply port may be positioned below the downstream opening. According to this configuration, even when the upstream sub-tank or the downstream sub-tank reaches the minimum water level, the water head difference between the upstream sub-tank or the downstream sub-tank and the head corresponding to the sub-tank is maintained within a predetermined range. Liquid leakage from the liquid can be prevented.

  According to the present invention, a driving source for supplying liquid from the main tank to the plurality of sub tanks is unnecessary, and the apparatus can be downsized.

1 is a schematic side view showing an ink jet printer according to a first embodiment of the present invention. It is a schematic side view which shows the main tank with which the mounting part of the printer of FIG. 1 was mounted | worn, and the four subtanks contained in the said printer. FIG. 2 is a plan view showing a recording module included in the printer of FIG. 1. FIG. 2 is a block diagram illustrating an electrical configuration of the printer of FIG. 1. It is a schematic side view corresponding to FIG. 2 which shows the condition at the time of initial introduction in time series. FIG. 3 is a schematic side view corresponding to FIG. 2, showing the state of ink supply from the main tank to the sub tank in time series using the printer. FIG. 2 is a flowchart showing control contents executed by a control unit of the printer of FIG. 1. It is a schematic side view corresponding to FIG. 2 which shows the main tank with which the mounting part of the inkjet printer which concerns on 2nd Embodiment of this invention was mounted | worn, and the four subtanks contained in the said printer. It is a schematic side view corresponding to FIG. 1 which shows the inkjet printer which concerns on 3rd Embodiment of this invention. FIG. 10 is a schematic side view corresponding to FIG. 2, showing a main tank mounted on the mounting portion of the printer of FIG. 9 and two sub tanks included in the printer. It is a schematic side view corresponding to FIG. 10 which shows the main tank with which the mounting part of the inkjet printer which concerns on 4th Embodiment of this invention was mounted | worn, and the two subtanks contained in the said printer. It is a schematic side view corresponding to FIG. 11 which shows the main tank with which the mounting part of the inkjet printer which concerns on 5th Embodiment of this invention was mounted | worn, and the two subtanks contained in the said printer. It is a schematic side view corresponding to FIG. 2 which shows the main tank and four sub tanks which are included in the inkjet printer which concerns on 6th Embodiment of this invention.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.

  First, with reference to FIG. 1 etc., the whole structure of the inkjet printer 1 which concerns on 1st Embodiment of this invention is demonstrated.

  As shown in FIG. 1, the printer 1 includes a housing 1 a, recording modules 50 a to 50 d, a transport unit 20, a storage unit 3, a receiving unit 4, and a control unit 100. The recording modules 50a to 50d, the transport unit 20, the storage unit 3, the receiving unit 4, and the control unit 100 are arranged in the housing 1a.

  The printer 1 further includes a mounting portion 70 and four sub tanks 61a to 61d as shown in FIG. The mounting portion 70 is a portion provided in the housing 1a to which a cartridge-type main tank 71 can be attached and detached. The main tank 71 has a main space 72 for storing ink. The four sub tanks 61a to 61d are disposed below the mounting portion 70 in the housing 1a, and have sub spaces 62a to 62d for storing ink supplied from the main space 72, respectively.

  The recording modules 50a to 50d have the same configuration and include heads 51a to 51d, respectively. The heads 51a to 51d are connected to the sub tanks 61a to 61d via pipes 85 to 88 and pumps 59a to 59d (see FIG. 2), respectively. When the pumps 59a to 59d are driven by the control of the control unit 100, the ink stored in the sub spaces 62a to 62d is supplied to the heads 51a to 51d via the tubes 85 to 88, respectively.

  The transport unit 20 includes an upstream transport unit 21 and a downstream transport unit 31. The upstream transport unit 21 forms paths R1x to R4x through which the paper P is transported from the storage unit 3 toward the module paths Ra to Rd of the recording modules 50a to 50d. The downstream transport unit 31 forms paths R1y to R4y along which the paper P is transported from the downstream ends of the in-module paths Ra to Rd toward the receiving unit 4.

  The paths R1x and R2x have a common part from the accommodating portion 3 to the branch position A1, branch at the branch position A1, and go to different in-module paths Ra and Rb, respectively. The paths R2x and R3x have a common part from the accommodating portion 3 to the branch position A2, branch at the branch position A2, and go to different in-module paths Rb and Rc, respectively. The paths R3x and R4x have a common part from the accommodating portion 3 to the branch position A3, branch at the branch position A3, and go to different in-module paths Rc and Rd, respectively. The paths R1y and R2y extend from the downstream ends of the in-module paths Ra and Rb, which are different from each other, join at the joining position B1, and have a common part from the joining position B1 to the receiving part 4. The paths R2y and R3y extend from the downstream ends of the in-module paths Rb and Rc different from each other, merge at the joining position B2, and have a common part from the joining position B2 to the receiving part 4. The paths R3y and R4y extend from the downstream ends of the in-module paths Rc and Rd, which are different from each other, merge at the joining position B3, and have a common part from the joining position B3 to the receiving part 4.

  The upstream transport unit 21 includes a paper feed roller 22, roller pairs 26a to 26d, guides 23, 25a to 25d, and switching units 28a to 28c. The downstream transport unit 31 includes roller pairs 36a to 36e and guides 33 and 35a to 35d.

  The paper feed roller 22 is disposed at a position in contact with the uppermost paper P in the storage unit 3. The paper feed roller 22 rotates when the paper feed motor 22M (see FIG. 4) is driven under the control of the control unit 100. Accordingly, the uppermost sheet P in the storage unit 3 is sent out from the storage unit 3.

  Each of the roller pairs 26a to 26d and 36a to 36e includes two rollers that are in contact with each other, and is configured to convey the paper P while being sandwiched between the two rollers. One of the two rollers constituting each of the roller pairs 26a to 26d is a drive roller, and rotates when the upstream conveyance motor 26M (see FIG. 4) is driven under the control of the control unit 100. One of the two rollers constituting each of the roller pairs 36a to 36e is a drive roller, and rotates when the downstream conveyance motor 36M (see FIG. 4) is driven under the control of the control unit 100. The other of the two rollers constituting each of the roller pairs 26a to 26d and 36a to 36e is a driven roller that rotates in the opposite direction to the driving roller while contacting the driving roller as the driving roller rotates. By rotation of the roller pairs 26a to 26d, the paper P sent out from the storage unit 3 by the paper feed roller 22 is conveyed toward one of the in-module paths Ra to Rd. The sheet P sent out from the in-module paths Ra to Rd is conveyed toward the receiving unit 4 by the rotation of the roller pairs 36a to 36e.

  The guides 23, 25a to 25d, 33, and 35a to 35d are configured to demarcate paths R1x to R4x and R1y to R4y, respectively, and include a pair of plates that are spaced apart from each other with a gap.

  The switching units 28a to 28c include swing members 28a1 to 28c1 and switching motors 28aM to 28cM (see FIG. 4), respectively. The swing members 28a1 to 28c1 are disposed at the branch positions A1 to A3, respectively, and can swing around a pin 1a4 formed on the housing 1a. The control motor 100 controls the switching motors 28aM to 28cM. Is driven, a first position indicated by a solid line in FIG. 1 and a second position indicated by a broken line in FIG. 1 can be taken.

  When the swing member 28a1 is in the first position, the path R1x is opened and the path R2x is closed at the branch position A1. Therefore, the sheet P conveyed from the storage unit 3 to the branch position A1 is conveyed toward the in-module path Ra along the path R1x. When the swing member 28a1 is in the second position, the path R1x is closed and the path R2x is opened at the branch position A1. Accordingly, the sheet P conveyed from the storage unit 3 to the branch position A1 is conveyed along the path R2x toward the in-module path Rb.

  When the swing member 28b1 is in the first position, the paths R1x and R2x are opened and the path R3x is closed at the branch position A2. Therefore, the sheet P conveyed from the storage unit 3 to the branch position A2 is conveyed toward the branch position A1 along the common portion of the paths R1x and R2x. When the swing member 28b1 is in the second position, the paths R1x and R2x are closed and the path R3x is opened at the branch position A2. Accordingly, the sheet P conveyed from the storage unit 3 to the branch position A2 is conveyed toward the in-module path Rc along the path R3x.

  When the swing member 28c1 is in the first position, the paths R1x to R3x are opened and the path R4x is closed at the branch position A3. Accordingly, the sheet P conveyed from the storage unit 3 to the branch position A3 is conveyed toward the branch position A2 along the common part of the paths R1x to R3x. When the swing member 28c1 is in the second position, the paths R1x to R3x are closed and the path R4x is opened at the branch position A3. Therefore, the sheet P conveyed from the storage unit 3 to the branch position A3 is conveyed along the path R4x toward the in-module path Rd.

  The accommodating portion 3 and the receiving portion 4 are constituted by a tray having an upper surface opened, and can be attached to and detached from the housing 1a in the sub-scanning direction. The storage unit 3 and the receiving unit 4 can store and receive a plurality of sheets P, respectively, and can store and receive a plurality of types of sheets P, respectively.

  The sub-scanning direction is a direction parallel to the horizontal plane and parallel to the downstream part of the paths R1x to R4x, the intra-module paths Ra to Rd, and the upstream part of the paths R1y to R4y. The main scanning direction is a direction parallel to the horizontal plane and orthogonal to the sub-scanning direction. The vertical direction is a direction orthogonal to the sub-scanning direction and the main scanning direction.

  The control unit 100 includes a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory: including a nonvolatile RAM), an ASIC (Application Specific Integrated Circuit), and an I / F (Interface). ), I / O (Input / Output Port) and the like. The ROM stores programs executed by the CPU, various fixed data, and the like. The RAM temporarily stores data necessary for program execution. The ASIC performs rewriting and rearrangement of image data (for example, signal processing and image processing). The I / F performs data transmission / reception with an external device (for example, a PC connected to the printer 1). I / O inputs / outputs detection signals of various sensors.

  Next, the recording modules 50a to 50d will be described in more detail with reference to FIG.

  Each of the recording modules 50 a to 50 d includes heads 51 a to 51 d, a carriage 52, and an individual conveyance unit 53.

  Each of the heads 51 a to 51 d is a serial type, has a substantially rectangular parallelepiped shape, and is supported by the housing 1 a via the carriage 52. The upper surfaces of the heads 51 a to 51 d are fixed to the carriage 52. The lower surfaces of the heads 51a to 51d are ejection surfaces in which a plurality of ejection ports 51x are opened. In FIG. 3, the discharge port 51 x to be drawn with a dotted line is drawn with a solid line for explanation.

  The carriage 52 is configured to be reciprocally movable in the main scanning direction by a carriage moving unit 52x. The carriage moving unit 52x includes guides 52g1 and 52g2, pulleys 52p1 and 52p2, a belt 52b, and a carriage motor 52M. The guides 52g1 and 52g2 have a rectangular shape when viewed from the vertical direction, and are separated from each other in the sub-scanning direction. The guides 52g1 and 52g2 sandwich the upper portions of the corresponding heads 51a to 51d and support both ends of the carriage 52 in the sub scanning direction so as to be slidable in the main scanning direction. The pulleys 52p1 and 52p2 are rotatably supported at one end and the other end of the guide 52g2 in the main scanning direction, respectively. The pulleys 52p1 and 52p2 have the same diameter and are disposed at the same position in the sub-scanning direction. The belt 52b is an endless belt spanned around the pulleys 52p1 and 52p2, and travels with the rotation of the pulleys 52p1 and 52p2. The carriage 52 is fixed to the belt 52b. The carriage motor 52M has a cylindrical shape elongated in the vertical direction, and is fixed to the lower surface of the guide 52g2. The rotation shaft of the carriage motor 52M is attached to the pulley 52p1 and extends in the vertical direction. The pulley 52p1 is a drive pulley, and rotates forward and backward when the carriage motor 52M is driven under the control of the control unit 100. Along with this, the belt 52b travels. The pulley 52p2 is a driven pulley and rotates as the belt 52b travels.

  With the operation of each part of the carriage moving unit 52x, the carriage 52 reciprocates in the main scanning direction while supporting the corresponding heads 51a to 51d. At this time, the control unit 100 controls the heads 51a to 51d and ejects ink from the ejection ports 51x at a desired timing, whereby an image is recorded on the paper P.

  The individual conveyance unit 53 is configured to intermittently convey the paper P in the direction D along the in-module paths Ra to Rd, and includes a pair of rollers 53a and 53b and an individual conveyance motor 53M (see FIG. 4). . The roller pairs 53a and 53b rotate when the individual transport motor 53M is driven under the control of the control unit 100. As a result, the paper P is conveyed in the direction D. The direction D is parallel to the sub-scanning direction and is a direction from upstream to downstream of the in-module paths Ra to Rd. The roller pairs 53a and 53b extend in the main scanning direction and sandwich the head 51 in the sub scanning direction. A platen 54 is disposed between the pair of rollers 53a and 53b at a position facing the discharge surface. The upper surface 54a of the platen 54 supports the paper P from below. A gap suitable for recording is formed between the ejection surface and the upper surface 54a. The roller pairs 53 a and 53 b and the platen 54 are supported by a pair of flanges 56. The pair of flanges 56 extend in the sub scanning direction and are separated from each other in the main scanning direction.

  The control unit 100 reciprocates the carriage 52 in the sub-scanning direction during the intermittent conveyance operation in which the individual conveyance unit 53 intermittently conveys the paper P in the direction D and the conveyance stop period of the paper P during the intermittent conveyance operation. Each of the recording modules 50a to 50d is controlled so as to perform a scanning operation for ejecting ink from the ejection port 51x while being moved.

  Next, the mounting unit 70, the main tank 71, and the sub tanks 61a to 61d will be described in more detail with reference to FIG.

  The main tank 71 mounted on the mounting unit 70 and the four sub tanks 61a to 61d overlap when viewed from the vertical direction.

  The mounting portion 70 has a wall 70a that defines a space in which the main tank 71 is disposed. The vicinity of one end of each of the tubes 81, 91, and 95 protrudes from the bottom surface, the side surface, and the top surface of the wall 70a. The opening at one end (upper end) of the tube 81 corresponds to the main outlet 75, and the opening at one end of the tube 91 corresponds to the main opening 76. The pipe 95 is an atmospheric communication pipe, and a valve 96 is provided in the middle thereof. When the main tank 71 is mounted on the mounting portion 70, the vicinity of one end of each of the pipes 81, 91, 95 passes through the wall that defines the main space 72 in the main tank 71. As a result, the main outlet 75 and the main opening 76 communicate with the main space 72. The main opening 76 is located above the liquid level of the ink stored in the main space 72 and above the main outlet 75. The valve 96 blocks the communication between the main space 72 and the atmosphere when the difference between the pressure of the main space 72 and the pressure of the atmosphere (the external space of the main space 72) is equal to or less than a predetermined value, regardless of the control of the control unit 100. The blocking position to be taken is taken, and when the difference exceeds a predetermined value, the permission position for allowing the communication between the main space 72 and the atmosphere is taken.

  Of the four sub tanks 61a to 61d, the sub tank 61a is located at the uppermost position, the sub tank 61b is located second from the top, the sub tank 61c is third from the top, and the sub tank 61d is located at the bottom. Also, regarding the ink supply direction from the main tank 71 to the sub tanks 61a to 61d, of the four sub tanks 61a to 61d, the sub tank 61a is located on the most upstream side, and the sub tank 61b is located on the second upstream side. The sub tank 61c is located on the third upstream side, and the sub tank 61d is located on the most downstream side. Hereinafter, “upstream side” and “downstream side” in the ink supply direction from the main tank 71 to the sub tanks 61a to 61d are simply referred to as “upstream side” and “downstream side”, respectively.

  The sub tanks 61a to 61d have substantially the same configuration except for the arrangement of the tubes 81 to 84 and 91 and the detection positions of the sensors 6a to 6d.

  At the upper walls that define the sub spaces 62a to 62d in the sub tanks 61a to 61d, air communication ports 63a to 63d for communicating the sub spaces 62a to 62d with the atmosphere are provided.

  The tubes 81 to 84 extend in the vertical direction and define ink flow paths 81x to 84x, respectively. The pipe 81 connects the main tank 71 and the sub tank 61a, the pipe 82 connects the sub tank 61a and the sub tank 61b, the pipe 83 connects the sub tank 61b and the sub tank 61c, and the pipe 84 connects the sub tank. 61c and the sub tank 61d are connected. The openings at the lower ends of the tubes 81 to 84 correspond to the inlets 64a to 64d, and the openings at the upper ends of the tubes 82 to 84 correspond to the outlets 65a to 65c. The inlets 64a to 64d communicate with the subspaces 62a to 62d, respectively, and the outlets 65a to 65c communicate with the subspaces 62a to 62c, respectively.

  The ink flow path 81x extends from the main outlet 75 to the inlet 64a, and is configured such that ink is supplied from the main space 72 to the sub space 62a. The ink flow path 82x extends from the outlet 65a to the inlet 64b, and is configured such that ink is supplied from the sub space 62a to the sub space 62b. The ink flow path 83x extends from the outlet 65b to the inlet 64c, and is configured such that ink is supplied from the sub space 62b to the sub space 62c. The ink flow path 84x extends from the outlet 65c to the inlet 64d, and is configured such that ink is supplied from the sub space 62c to the sub space 62d.

  The ink flow paths 81x to 84x are configured so that the resistance becomes smaller as the flow path is downstream. That is, the resistance of the ink flow path 82x is smaller than the resistance of the ink flow path 81x. The resistance of the ink flow path 83x is smaller than the resistance of the ink flow path 82x. The resistance of the ink flow path 84x is smaller than the resistance of the ink flow path 83x. Such a magnitude relationship of the resistances of the ink flow paths 81x to 84x may be realized by, for example, the inner diameter of the pipe that defines the flow path, the material that constitutes the pipe, and the like. As an example, the diameter of the ink flow path 82x may be larger than the diameter of the ink flow path 81x. The diameter of the ink flow path 83x may be larger than the diameter of the ink flow path 82x. The diameter of the ink flow path 84x may be larger than the diameter of the ink flow path 83x.

  The openings constituting the ends of the ink flow paths 81x to 84x have the following vertical positional relationship. That is, the main outlet 75 is located above the inlets 64a to 64d and the outlets 65a to 65c. The outlet 65a is located above the inlets 64a to 64d and the outlets 65b and 65c. The inlet 64a is located above the inlets 64b to 64d and the outlets 65b and 65c. The outlet 65b is located above the inlets 64b to 64d and the outlet 65c. The inlet 64b is located above the inlets 64c and 64d and the outlet 65c. The outlet 65c is located above the inlets 64c and 64d. The inlet 64c is located above the inlet 64d.

  The pipe 91 branches from the main tank 71 toward the four sub tanks 61a to 61d, and demarcates gas flow paths 91a to 91d corresponding to the sub tanks 61a to 61d, respectively. The gas flow paths 91 a and 91 b extend from different sub-tanks 61 a and 61 b, merge at the merge position C 1, and have a common part from the merge position C 1 to the main opening 76. The gas flow paths 91b and 91c extend from different sub-tanks 61b and 61c, merge at the merge position C2, and have a common portion from the merge position C2 to the main opening 76. The gas flow paths 91c and 91d extend from different sub-tanks 61c and 61d, merge at the merge position C3, and have a common portion from the merge position C3 to the main opening 76. The tube 91 has four other ends with respect to one end of the tube 91 (the portion where the main opening 76 is provided), and the four other ends 66a to 66d communicate with the subspaces 62a to 62d, respectively. .

  The gas flow path 91a extends from the opening 66a to the main opening 76, and when the liquid level of the ink in the sub space 62a is located below the opening 66a, the gas flow path 91a is connected to the main space 72 via the opening 66a and the main opening 76. It is configured to communicate with the atmosphere. The gas flow path 91a allows the main space 72 and the atmosphere to communicate with each other through the gas flow path 91a when the ink level in the sub space 62a reaches the opening 66a and the opening 66a is closed with ink. It is configured to block. The gas flow path 91b extends from the opening 66b to the main opening 76, and when the ink level in the sub space 62b is located below the opening 66b, the gas flow path 91b is connected to the main space 72 via the opening 66b and the main opening 76. It is configured to communicate with the atmosphere. The gas flow path 91b allows the main space 72 and the atmosphere to communicate with each other through the gas flow path 91b when the ink level in the sub space 62b reaches the opening 66b and the opening 66b is closed with ink. It is configured to block. The gas flow path 91c extends from the opening 66c to the main opening 76, and when the liquid level of the ink in the sub space 62c is located below the opening 66c, the gas flow path 91c is connected to the main space 72 via the opening 66c and the main opening 76. It is configured to communicate with the atmosphere. Further, the gas flow path 91c allows the main space 72 and the atmosphere to communicate with each other through the gas flow path 91c when the ink level in the sub space 62c reaches the opening 66c and the opening 66c is closed with ink. It is configured to block. The gas flow passage 91d extends from the opening 66d to the main opening 76, and when the liquid level of the ink in the sub space 62d is located below the opening 66d, the gas flow path 91d is connected to the main space 72 via the opening 66d and the main opening 76. It is configured to communicate with the atmosphere. The gas flow path 91d allows the main space 72 and the atmosphere to communicate with each other through the gas flow path 91d when the ink level in the sub space 62d reaches the opening 66d and the opening 66d is closed with ink. It is configured to block.

  The gas flow paths 91a to 91d are configured to have a smaller resistance as they correspond to the downstream side sub tanks 61a to 61d. That is, the resistance of the gas flow path 91b is smaller than the resistance of the gas flow path 91a. The resistance of the gas flow path 91c is smaller than the resistance of the gas flow path 91b. The resistance of the gas flow path 91d is smaller than the resistance of the gas flow path 91c. Such a magnitude relationship of the resistances of the gas flow paths 91a to 91d may be realized by, for example, the inner diameter of the pipe that defines the flow path, the material constituting the pipe, and the like. As an example, the diameter of the gas channel 91b may be larger than the diameter of the gas channel 91a. The diameter of the gas flow path 91c may be larger than the diameter of the gas flow path 91b. The diameter of the gas flow path 91d may be larger than the diameter of the gas flow path 91c.

  The openings constituting the ends of the gas flow paths 91a to 91d have the following vertical positional relationship. That is, the main opening 76 is located above the openings 66a to 66d. The opening 66a is located above the openings 66b to 66d. The opening 66b is located above the openings 66c and 66d. The opening 66c is located above the opening 66d. As another example of the means for realizing the magnitude relationship of the resistance of the gas flow paths 91a to 91d as described above, the diameter of the opening 66b may be larger than the diameter of the opening 66a. The diameter of the opening 66c may be larger than the diameter of the opening 66b. The diameter of the opening 66d may be larger than the diameter of the opening 66c.

  Furthermore, each opening 66a-66d exists in the position which satisfy | fills the following conditions. The opening 66a is located below the outlet 65a. The opening 66b is located below the outlet 65b. The opening 66c is located below the outlet 65c. The opening 66d is located below the outlets 65a to 65c. Vertical distances Da to Dd from the bottoms of the subspaces 62a to 62d to the openings 66a to 66d have a relationship of Da = Db = Dc <Dd. The vertical distances Da 'to Dc' from the bottoms of the sub spaces 62b to 62d to the outlets 65a to 65c are in the relationship of Da '= Db' = Dc 'and are equal to the distance Dd. That is, the relationship Da = Db = Dc <Dd = Da ′ = Db ′ = Dc ′ is established.

  Gas permeable membranes 66ax to 66dx and 76x are provided in the openings 66a to 66d and 76, respectively. Each of the gas permeable membranes 66ax to 66dx and 76x is configured to block the corresponding openings 66a to 66d and 76, allow gas to pass, and not allow liquid to pass.

  Supply ports 67a to 67d, which are openings at one ends of the pipes 85 to 88, are provided on lower walls that define the sub spaces 62a to 62d in the sub tanks 61a to 61d, respectively. Openings at the other ends of the tubes 85 to 88 are provided in the heads 51a to 51d, respectively. Pumps 59a to 59d are provided in the middle of the pipes 85 to 88, respectively. Via the pipes 85 to 88, the subspaces 62a to 62d communicate with the discharge ports 51x of the corresponding heads 51a to 51d.

  The supply port 67a is located below the outlet 65a. The supply port 67b is located below the outlet 65b. The supply port 67c is located below the outlet 65c. The supply port 67d is located below the opening 66d. The outlets 65a to 65c and the openings 66a to 66d are arranged at positions where the water head difference from the corresponding head is within a predetermined range. The predetermined range is a range in which the ejection performance of the head is properly maintained.

  Sensors 6a to 6d are provided for the sub-tanks 61a to 61d. The sensors 6a to 6d are configured to output signals indicating the liquid level height of the ink in the sub spaces 62a to 62d, respectively. The heights of the detection positions of the sensors 6a to 6d are the same as the heights of the openings 66a to 66d, respectively. The sensors 6a to 6d are turned off when the liquid level of the ink in the sub spaces 62a to 62d is lower than the height of the openings 66a to 66d, and turned on when the height is higher than the height of the openings 66a to 66d. Output a signal.

  Next, with reference to FIGS. 5 and 6, the situation at the time of initial introduction and the situation of ink supply from the main tank 71 to the sub tanks 61a to 61d during use of the printer will be described. The initial introduction refers to ink supply from the main tank 71 to the sub tanks 61a to 61d in an empty state.

  5 and 6, the pipes 85 to 88, the pumps 59a to 59d, and the heads 51a to 51d are not shown. Ink movement is indicated by thick arrows, and gas movement is indicated by white arrows.

  In the present embodiment, when the main tank 71 is mounted on the mounting portion 70 when the sub tanks 61a to 61d are empty, initial introduction is started (see FIG. 5). At the start of the initial introduction, as shown in FIG. 5A, the liquid levels of the ink in the sub spaces 62a to 62d are positioned below the openings 66a to 66d, respectively. That is, the amount of ink in the subspaces 62a to 62d is “0”. At this time, the main space 72 communicates with the atmosphere via the gas flow paths 91 a to 91 d, and gas can be supplied to the main space 72. For this reason, the ink in the main space 72 flows out of the main outlet 75 due to its own weight, and flows into the sub space 62a through the ink flow path 81x.

  When the ink level in the sub space 62a reaches the height of the opening 66a, the opening 66a is closed with ink, and the supply of gas from the sub space 62a to the main space 72 via the gas flow path 91a is stopped. . However, at this time, since the supply of gas to the main space 72 through the gas flow paths 91b to 91d is maintained, the ink in the main space 72 continues to flow out from the main outlet 75 due to its own weight. Then, as shown in FIG. 5B, after the ink level in the sub space 62a reaches the height of the outlet 65a, if the ink further flows into the sub space 62a, the ink in the sub space 62a becomes It flows out from the outlet 65a and flows into the sub space 62b through the ink flow path 82x.

  When the ink level in the sub space 62b reaches the height of the opening 66b, the opening 66b is closed with ink, and the supply of gas from the sub space 62b to the main space 72 via the gas flow path 91b is stopped. . However, at this time, since the supply of gas to the main space 72 via the gas flow paths 91c and 91d is maintained, the ink in the main space 72 continues to flow out from the main outlet 75 due to its own weight. Then, as shown in FIG. 5C, after the ink level in the sub space 62b reaches the height of the outlet 65b, if the ink further flows into the sub space 62b, the ink in the sub space 62b becomes It flows out from the outlet 65b and flows into the sub space 62c through the ink flow path 83x.

  When the liquid level of the ink in the sub space 62c reaches the height of the opening 66c, the opening 66c is closed with ink, and supply of gas from the sub space 62c to the main space 72 via the gas flow path 91c is stopped. . However, at this time, since the supply of gas to the main space 72 through the gas flow path 91d is maintained, the ink in the main space 72 continues to flow out of the main outlet 75 due to its own weight. Then, as shown in FIG. 5D, after the liquid level of the ink in the sub space 62c reaches the height of the outlet 65c, if the ink further flows into the sub space 62c, the ink in the sub space 62c becomes It flows out from the outlet 65c and flows into the sub space 62d through the ink flow path 84x.

  When the liquid level of the ink in the sub space 62d reaches the height of the opening 66d, as shown in FIG. 2, the opening 66d is closed with ink, and the sub space 62d to the main space 72 via the gas flow path 91d is closed. The gas supply is stopped. At this time, supply of gas to the main space 72 via the gas flow paths 91a to 91d is stopped, and communication between the main space 72 and the atmosphere is blocked. Thereby, the ink in the main space 72 does not flow out from the main outlet 75. That is, the ink supply from the main tank 71 to the sub tanks 61a to 61d is stopped. This completes the initial introduction.

  When the initial introduction is completed, the sub tanks 61a to 61d are at the maximum water level as shown in FIG. The maximum water levels of the sub tanks 61a to 61c are the same as the heights of the outlets 65a to 65c, respectively, and the maximum water level of the sub tank 61d is the same as the height of the opening 66d.

  After the initial introduction, when the printer 1 is used and ink in the subspaces 62a to 62d is consumed with recording on the paper P, the liquid level height of the ink in the subspaces 62a to 62d is the opening 66a. May be less than ~ 66d height.

  When the liquid surface height of the ink in the sub space 62a becomes less than the height of the opening 66a, as shown in FIG. 6, the opening 66a is not blocked by the ink, so that the sub liquid passing through the gas flow path 91a is stopped. Gas is supplied from the space 62a to the main space 72. Thereby, the ink in the main space 72 flows out of the main outlet 75 due to its own weight, and flows into the sub space 62a through the ink flow path 81x. When the liquid level of the ink in the sub space 62a reaches the height of the opening 66a, the opening 66a is closed again with ink, so that the gas from the sub space 62a to the main space 72 via the gas flow path 91a is closed. Is stopped. As a result, communication between the main space 72 and the atmosphere is blocked, and ink in the main space 72 does not flow out from the main outlet 75. That is, the ink supply from the main tank 71 to the sub tank 61a is stopped.

  The same applies to the case where the ink level in the subspaces 62b to 62d is less than the height of the openings 66b to 66d, respectively. That is, as the gas is supplied to the main space 72 through the openings 66b to 66d, the ink flows from the main space 72 into the sub spaces 62b to 62d, and then the openings 66b to 66d are closed again with the ink. Thus, the ink supply from the main tank 71 to the sub tanks 61b to 61d is stopped.

  Next, the control contents executed by the control unit 100 will be described with reference to FIG. The control unit 100 repeatedly executes the routine shown in FIG. 7 while the printer 1 is powered on.

  First, the control unit 100 determines whether or not the main tank 71 exists in the mounting unit 70 (S1). The determination of S1 may be performed based on a signal from a sensor that outputs a signal indicating the presence or absence of the main tank 71 in the mounting unit 70, for example. Alternatively, the determination of S1 is performed by any other method (for example, based on electrical continuity caused by the contact between the electrode provided on the wall 70a and the electrode provided on the outer surface of the main tank 71). Good.

  When the main tank 71 does not exist in the mounting unit 70 (S1: NO), the control unit 100 repeats the process of S1. When the main tank 71 exists in the mounting unit 70 (S1: YES), the control unit 100 determines whether initial introduction is performed (S2). For example, the controller 100 determines that the initial introduction is performed (S2: YES) in the first S2 after determining that the main tank 71 exists in S1, and determines that the main tank 71 exists in S1. In S2 after the second time, it is determined that the initial introduction is not performed (S2: NO). Alternatively, the control unit 100 may perform the determination of S2 based on other means (for example, the storage contents of a memory provided in the main tank 71).

  When the initial introduction is performed (S2: YES), has the control unit 100 output an ON signal from the sensor 6d (that is, ink supply from the main tank 71 to the sub tanks 61a to 61d in the initial introduction has been completed)? It is determined whether or not (S3).

  When the ON signal is output from the sensor 6d (S3: YES), the control unit 100 controls the pumps 59a to 59d to perform purging (S4). The purge is an operation of forcibly pumping ink to the four heads 51a to 51d by driving the pumps 59a to 59d and forcibly discharging the ink from all the ejection ports 51x of the four heads 51a to 51d. Say. After S4, the control unit 100 ends the routine.

  When the ON signal is not output from the sensor 6d (S3: NO), the control unit 100 determines whether or not a predetermined time has elapsed after starting the determination of S3 (S5). The predetermined time is determined based on the time required from the start of initial introduction until the sensor 6d is turned on. When the predetermined time has not elapsed (S5: NO), the control unit 100 returns the process to S3. When the predetermined time has elapsed (S5: YES), the control unit 100 performs error notification by the output means (display, speaker, etc.) of the printer 1 (S6). This is because if the initial introduction is not completed even after a predetermined time has elapsed, it is considered that there is a problem with the ink supply system from the main tank 71 to the sub tanks 61a to 61d. After S6, the control unit 100 ends the routine.

  When the initial introduction is not performed (S2: NO), the control unit 100 outputs an OFF signal from any of the sensors 6a to 6d (that is, the ink level in any of the sub spaces 62a to 62d). Is lower than the height of the openings 66a to 66d) (S7).

  When no OFF signal is output from any of the sensors 6a to 6d (S7: NO), that is, when the ink level in the subspaces 62a to 62d is equal to or higher than the heights of the openings 66a to 66d, The control unit 100 ends the routine.

  When an OFF signal is output from any of the sensors 6a to 6d (S7: YES), the control unit 100 determines whether or not a predetermined time has elapsed after starting the determination of S7 (S8). When the predetermined time has not elapsed (S8: NO), the control unit 100 returns the process to S7. When the predetermined time has elapsed (S8: YES), the control unit 100 performs error notification by the output means (display, speaker, etc.) of the printer 1 (S6). This is because if the ink supply to the sub spaces 62a to 62d is not completed even after the predetermined time has elapsed, it is considered that there is a problem with the ink supply system from the main tank 71 to the sub tanks 61a to 61d. After S6, the control unit 100 ends the routine.

  The correspondence between the constituent elements of this embodiment and the constituent elements defined in the present invention is as follows. That is, the head 51a corresponds to the first head of the present invention, the head 51d corresponds to the second head of the present invention, and the heads 51b and 51c correspond to the third head of the present invention. The sub tank 61a corresponds to the upstream sub tank of the present invention, the sub tank 61d corresponds to the downstream sub tank of the present invention, and the sub tanks 61b and 61c correspond to the intermediate sub tank of the present invention. The sub space 62a corresponds to the upstream sub space of the present invention, the sub space 62d corresponds to the downstream sub space of the present invention, and the sub spaces 62b and 62c correspond to the intermediate sub space of the present invention. The atmospheric communication port 63a corresponds to the upstream atmospheric communication port of the present invention, the atmospheric communication ports 63b and 63c correspond to the intermediate atmospheric communication port of the present invention, and the atmospheric communication port 63d corresponds to the downstream atmospheric communication port of the present invention. The ink flow path 81x corresponds to the first liquid flow path of the present invention, and the ink flow paths 82x to 84x correspond to the second liquid flow path of the present invention. The inlet 64a corresponds to the upstream inlet of the present invention, the inlet 64d corresponds to the downstream inlet of the present invention, and the inlets 64b and 64c correspond to the intermediate inlet of the present invention. The outlet 65a corresponds to the upstream outlet of the present invention, and the outlets 65b and 65c correspond to the intermediate outlet of the present invention. The gas flow path 91d corresponds to the first gas flow path of the present invention, the gas flow path 91a corresponds to the second gas flow path of the present invention, and the gas flow paths 91b and 91c correspond to the third gas flow path of the present invention. Equivalent to. The opening 66a corresponds to the upstream opening of the present invention, the opening 66d corresponds to the downstream opening of the present invention, and the openings 66b and 66c correspond to the intermediate opening of the present invention. The gas permeable film 76x corresponds to the main gas permeable film of the present invention, the gas permeable film 66dx corresponds to the first gas permeable film of the present invention, the gas permeable film 66ax corresponds to the second gas permeable film of the present invention, The gas permeable membranes 66bx and 66cx correspond to the third gas permeable membrane of the present invention. The supply port 67a corresponds to the upstream supply port of the present invention, and the supply port 67d corresponds to the downstream supply port of the present invention. The sensor 6a corresponds to the upstream sensor of the present invention, and the sensor 6d corresponds to the downstream sensor of the present invention. The pumps 59a to 59d correspond to the forced discharge part of the present invention.

  As described above, according to the present embodiment, when the ink level in the sub space 62d is located below the opening 66d, the main space 72 communicates with the atmosphere via the gas flow path 91d. In addition, gas is supplied to the main space 72. For this reason, the ink stored in the main space 72 flows out from the main outlet 75 by its own weight. The ink flowing out from the main outlet 75 flows into the sub space 62a through the ink flow path 81x. Thereafter, the ink level in the sub space 62a reaches the height of the outlet 65a. Thereafter, when ink further flows into the sub space 62a, the ink in the sub space 62a flows out from the outlet 65a and flows into the sub space 62d via the ink flow paths 82x to 84x. When the ink level in the sub space 62d reaches the height of the opening 66d, the opening 66d is closed with ink. When the opening 66d is closed with ink, the communication between the main space 72 and the atmosphere via the gas flow path 91d is blocked. As a result, no gas is supplied to the main space 72 via the gas flow path 91d, and the ink in the main space 72 does not flow out from the main outlet 75. That is, the ink supply from the main tank 71 to the sub tanks 61a to 61d is stopped. Thus, according to the present embodiment, ink is supplied from the main tank 71 to the sub tanks 61a to 61d without driving the drive source. That is, according to the present embodiment, a drive source for supplying ink from the main tank 71 to the sub tanks 61a to 61d is unnecessary, and the printer 1 can be downsized.

  According to this embodiment, in addition to the effect that a drive source is unnecessary, control for supplying ink from the main tank 71 to the sub tanks 61a to 61d is also unnecessary.

  The printer 1 includes a gas channel 91a in addition to the gas channel 91d. According to this configuration, when the amount of ink in the sub space 62a decreases due to an ink discharge operation or the like, ink can be replenished to the sub space 62a. Specifically, when the ink level in the sub space 62a is positioned below the opening 66a, the main space 72 communicates with the atmosphere via the gas flow path 91a, and gas is supplied to the main space 72. . Accordingly, ink is supplied from the main space 72 to the sub space 62a via the ink flow path 81x.

  The gas flow paths 91a and 91d have a common part. According to this configuration, the printer 1 can be further reduced in size by sharing the gas flow paths 91a and 91d.

  Gas permeable membranes 66ax and 66dx are provided in the openings 66a and 66d, respectively. In the absence of the gas permeable membranes 66ax and 66dx, when the printer 1 is inclined, the ink can enter the gas flow paths 91a and 91d. Further, when the gas permeable membranes 66ax and 66dx have a common portion, the ink supplied into the sub space 62a can enter the gas channel 91a and further the gas channel 91d from the opening 66a. In this case, both the gas supply to the main space 72 via the gas flow path 91d and the gas supply to the main space 72 via the gas flow path 91a are shut off, causing a problem in the ink supply from the main tank 71. obtain. On the other hand, according to the above configuration, by providing the gas permeable films 66ax and 66dx, it is possible to prevent the ink from entering the gas flow paths 91a and 91d and to prevent the occurrence of ink supply problems.

  The resistance of the gas channel 91d is smaller than the resistance of the gas channel 91a. When the resistances of the gas flow paths 91a and 91d are the same, the loss of ink supply to the sub tank 61d is large, and the ink supply speed to the sub tank 61d can be reduced. On the other hand, according to the above configuration, it is possible to suppress a decrease in the ink supply speed to the sub tank 61d.

  The printer 1 includes heads 51b and 51c and sub tanks 61b and 61c. The second liquid flow channel (the flow channel configured to supply ink from the sub space 62a to the sub space 62d) has an upstream flow channel and a downstream flow channel (if the inlet 64b is assumed to be an intermediate inlet), the ink flow The path 82x corresponds to the upstream flow path, the ink flow paths 83x and 84x correspond to the downstream flow path, and the ink flow paths 82x and 83x correspond to the upstream flow path when the inlet 64c is assumed to be an intermediate inlet. The flow path 84x corresponds to a downstream flow path). According to this configuration, even when three or more heads are provided, ink supply from the main tank 71 to the sub tanks 61a to 61d can be realized without driving the drive source.

  The resistance of the downstream flow path is smaller than the resistance of the upstream flow path. Specifically, when the inlet 64b is assumed to be an intermediate inlet, the resistance of the downstream flow paths (ink flow paths 83x and 84x) is smaller than the resistance of the upstream flow path (ink flow paths 82x). Assuming that the inlet 64c is an intermediate inlet, the resistance of the downstream flow path (ink flow path 84x) is smaller than the resistance of the upstream flow paths (ink flow paths 82x and 83x). According to this configuration, since the downstream ink flow path has a smaller resistance, the ink supply speed to the sub tanks 61a to 61d can be reduced by suppressing a decrease in the ink supply speed to the sub tanks on the downstream side. Can be aligned.

  The printer 1 has gas flow paths 91b and 91c in addition to the gas flow paths 91a and 91d. According to this configuration, when the amount of ink in the subspaces 62b and 62c decreases due to an ink ejection operation or the like, ink can be supplied to the subspaces 62b and 62c. Specifically, when the liquid level of the ink in the sub space 62b is located below the opening 66b, the main space 72 communicates with the atmosphere via the gas flow path 91b, and gas is supplied to the main space 72. . Accordingly, ink is supplied from the main space 72 to the sub space 62b through the ink flow path 82x. Similarly, when the ink level in the sub space 62c is positioned below the opening 66c, the main space 72 communicates with the atmosphere via the gas flow path 91c, and gas is supplied to the main space 72. Accordingly, ink is supplied from the main space 72 to the sub space 62c via the ink flow paths 82x and 83x.

  The gas flow paths 91a to 91d have a common part. According to this configuration, the printer 1 can be further reduced in size by sharing the gas flow paths 91a to 91d.

  Gas permeable membranes 66ax to 66dx are provided in the openings 66a to 66d, respectively. In the absence of the gas permeable membranes 66ax to 66dx, the ink can enter the gas flow paths 91a to 91d when the printer 1 is tilted. Further, when the gas flow paths 91a to 91d have a common portion, the ink supplied into the sub space 62a enters the gas flow path 91a and further the gas flow path 91d from the opening 66a, or the sub spaces 62b and 62c. The ink supplied inside may enter the gas flow paths 91b and 91c and further the gas flow path 91d from the openings 66b and 66c. In this case, all of the gas supply to the main space 72 via the gas flow paths 91 a to 91 d is blocked, and a problem may occur in the ink supply from the main tank 71. On the other hand, according to the above configuration, by providing the gas permeable films 66ax to 66dx, it is possible to prevent the ink from entering the gas flow paths 91a to 91d and to prevent the occurrence of ink supply problems.

  The resistance of the gas flow paths 91b and 91c is smaller than the resistance of the gas flow path 91a, and the resistance of the gas flow path 91d is smaller than the resistance of the gas flow paths 91b and 91c. According to the said structure, since it comprised so that resistance might become small as the gas flow path corresponding to a downstream subtank, the fall of the ink supply speed to a downstream subtank was suppressed, and subtank 61a-61d. The ink supply speed can be made uniform.

  The vertical distance Dd from the bottom of the sub space 62d to the opening 66d is larger than the vertical distance Da from the bottom of the sub space 62a to the opening 66a. The maximum water level of the sub tank 61d is the same as the height of the opening 66d. According to the above configuration, a larger amount of ink can be stored in the sub space 62d than when the distance Dd is equal to or less than the distance Da. That is, the volume of the sub space 62d can be used efficiently.

  The vertical distance Dd from the bottom of the sub space 62d to the opening 66d is equal to the vertical distance Da 'from the bottom of the sub space 62a to the outlet 65a. The maximum water level of the sub tank 61d is the same as the height of the opening 66d, and the maximum water level of the sub tank 61a is the same as the height of the outlet 65a. According to the above configuration, the height of the maximum water level with respect to the bottoms of the sub spaces 62a and 62d is equal in each of the sub tanks 61a and 61d. Therefore, the vertical position of the head 51a with respect to the sub tank 61a and the head 51d with respect to the sub tank 61d. Can be set to the same vertical position. That is, according to the above configuration, it is easy to set the positional relationship between the sub-tanks 61a and 61d and the corresponding heads 51a and 51d.

  When the control unit 100 determines that the ink level in the sub space 62d has reached a predetermined water level based on the signal output from the sensor 6d (S3: YES), the control unit 100 performs a purge (S4). . According to this configuration, at the time of initial introduction, it is possible to shorten the time from when the ink supply from the main tank 71 to the sub tanks 61a to 61d is completed until the purge is performed, and to reduce time loss.

  In addition to the sensor 6d, a sensor 6a is provided. According to the said structure, since the structure of the subtank 61a and the subtank 61d is shared, manufacture is easy. Further, when the time during which the liquid level of the ink in the sub space 62a and / or the sub space 62d does not reach the predetermined water level exceeds the predetermined time based on the signal output from the sensor 6a and / or the sensor 6d In addition, by limiting the ink ejection operation from the head corresponding to the sub-tank or performing error notification, it is possible to avoid problems such as idling (S3: NO → S5: YES → S6). Process, and S7: YES → S8: YES → See the process of S6). Further, it is possible to estimate the empty of the main tank 71 based on the signal output from the sensor a and / or the sensor 6d without providing a sensor that outputs a signal indicating the ink level in the main tank 71. Can do. Therefore, it is not necessary to provide the main tank 71 or the mounting portion 70 with a sensor that outputs a signal indicating the level of the ink level in the main tank 71, and the configuration of the main tank 71 or the mounting portion 70 can be simplified. It is.

  The mounting portion 70 is provided with a valve 96. When the valve 96 is not provided, if the atmospheric pressure decreases and the pressure difference between the main space 72 and the atmosphere increases, there may be a problem that the amount of ink supplied from the main space 72 becomes excessive. On the other hand, according to the above configuration, when the pressure difference exceeds a predetermined value, the valve 96 is switched from the blocking position to the permission position, and the communication is permitted from the state where the communication between the main space 72 and the atmosphere is blocked. Switch to state. Thereby, since the pressure in the main space 72 can be released to the atmosphere, the pressure difference between the main space 72 and the atmosphere is reduced, and the above problem can be reduced.

  The resistance of the ink flow paths 82x to 84x is smaller than the resistance of the ink flow path 81x. When the resistance of the ink flow path 81x and the resistance of the ink flow paths 82x to 84x are the same, the loss of ink supply to the sub tank 61d is large, and the ink supply speed to the sub tank 61d can be reduced. On the other hand, according to the above configuration, it is possible to suppress a decrease in the ink supply speed to the sub tank 61d.

  A gas permeable film 76 x is provided in the main opening 76. According to this configuration, it is possible to prevent ink from entering the main space 72 via the main opening 76.

  The supply port 67a is located below the outlet 65a, and the supply port 67d is located below the opening 66d. According to this configuration, even when the sub tank 61a or the sub tank 61d reaches the minimum water level, the water head difference between the sub tank 61a or the sub tank 61d and the heads 51a and 51d corresponding to the sub tank is maintained within a predetermined range. Ink leakage from the heads 51a and 51d can be prevented.

  Next, an inkjet printer according to a second embodiment of the present invention will be described with reference to FIG.

  The printer according to the second embodiment has the same configuration as that of the printer 1 according to the first embodiment, except for the configuration of the mounting portion and the sub tank. In FIG. 8, the same components as those in the first embodiment are denoted by the same reference numerals.

  In 2nd Embodiment, the main tank 71 with which the mounting part 70 was mounted | worn, and the four subtanks 61a-61d are in the position which overlaps regarding the perpendicular direction, and are arrange | positioned along with the horizontal direction. The sub tanks 61a to 61d are not separated from each other but are formed integrally. Each of the tubes 81 to 84 extends in the horizontal direction instead of the vertical direction. The pipes 81 to 84 are at positions different from each other in the vertical direction, and the pipes 81 to 84 are located downward as they are downstream. With respect to the vertical direction, the main outlet 75 and the inlet 64a are at the same position, the outlet 65a and the inlet 64b are at the same position, the outlet 65b and the inlet 64c are at the same position, and the outlet 65c and the inlet 64d are at the same position. It is in. The pipe 91 extends from the main tank 71 toward only the sub tank 61d without branching toward the four sub tanks 61a to 61d. That is, in the present embodiment, the gas flow paths 91a to 91c are omitted.

  Also in the second embodiment, the same effects as in the first embodiment can be obtained with the same configuration as in the first embodiment.

  Subsequently, an inkjet printer 301 according to a third embodiment of the present invention will be described with reference to FIGS. 9 and 10.

  The printer 301 according to the third embodiment has the same configuration as the printer 1 according to the first embodiment, except for the number of recording modules, the configuration of paths, and the number of sub tanks. In FIG.9 and FIG.10, the same code | symbol is attached | subjected to the same component as 1st Embodiment.

  The printer 301 includes two recording modules 50a and 50d. Accordingly, in the present embodiment, two sub tanks 61a and 61d are provided in the housing 1a instead of the four sub tanks 61a to 61d. That is, in this embodiment, the two recording modules 50b and 50c located in the center in the vertical direction among the four recording modules 50a to 50d of the first embodiment are omitted, and the four sub tanks 61a to 61a of the first embodiment are omitted. Two sub tanks 61b and 61c (intermediate sub tanks) located in the center in the vertical direction of 61d are omitted. The upstream transport unit 21 forms two paths R1x and R4x through which the paper P is transported from the storage unit 3 toward the module paths Ra and Rd of the recording modules 50a and 50d. The downstream transport unit 31 forms two paths R1y and R4y through which the paper P is transported from the downstream end of each of the intra-module paths Ra and Rd toward the receiving unit 4. Further, with the omission of the sub tanks 61b and 61c, the pipes 82 and 83 are omitted, and a pipe 384 is provided instead of the pipe 84. The tube 384 defines an ink flow path 384x corresponding to the second liquid flow path. The pipe 91 branches from the main tank 71 toward the two sub tanks 61a and 61d. That is, in this embodiment, the gas flow paths 91b and 91c (third gas flow path) are omitted. The gas flow paths 91a and 91d extend from the sub tanks 61a and 61d, merge at the merge position C1, and have a common portion from the merge position C1 to the main opening 76.

  Also in the third embodiment, the same effects as in the first embodiment can be obtained with the same configuration as in the first embodiment.

  Subsequently, an inkjet printer according to a fourth embodiment of the present invention will be described with reference to FIG.

  The printer according to the fourth embodiment has the same configuration as that of the printer 301 according to the third embodiment except for the configuration of the mounting portion and the sub tank. In FIG. 11, the same code | symbol is attached | subjected to the same component as 3rd Embodiment.

  In 4th Embodiment, the main tank 71 with which the mounting part 70 was mounted | worn, and the two sub tanks 61a and 61d are in the position which overlaps regarding the perpendicular direction, and are arrange | positioned along with the horizontal direction. The sub tanks 61a and 61d are not separated from each other but are formed integrally. Each tube 81, 384 extends in the horizontal direction, not in the vertical direction. The tubes 81 and 384 are at the same position with respect to the vertical direction. With respect to the vertical direction, the main outlet 75, the inlet 64a, the outlet 65a, and the inlet 64d are at the same position. The pipe 91 extends from the main tank 71 toward only the sub tank 61d without branching toward the two sub tanks 61a and 61d. That is, in this embodiment, the gas flow path 91a is omitted.

  Also in the fourth embodiment, the same effects as in the third embodiment can be obtained with the same configuration as in the third embodiment.

  Next, an inkjet printer according to a fifth embodiment of the invention will be described with reference to FIG.

  The printer according to the fifth embodiment has the same configuration as that of the printer according to the fourth embodiment except for the configuration of the mounting portion and the sub tank. In FIG. 12, the same code | symbol is attached | subjected to the same component as 4th Embodiment.

  In the fifth embodiment, the main tank 71 and the two sub tanks 61a and 61d mounted on the mounting unit 70 are in positions that partially overlap in the vertical direction and are arranged side by side in the horizontal direction. The pipes 81 and 384 are located at different positions with respect to the vertical direction, and the pipe 384 is located below the pipe 81. With respect to the vertical direction, the main outlet 75 and the inlet 64a are at the same position, and the outlet 65a and the inlet 64d are at the same position.

  Also in the fifth embodiment, the same effects as in the fourth embodiment can be obtained with the same configuration as in the fourth embodiment.

  Subsequently, an inkjet printer according to a sixth embodiment of the present invention will be described with reference to FIG.

  In the printer according to the sixth embodiment, the main tank 71 is not detachable from the mounting portion 70 (that is, not the cartridge type), and is installed in the housing 1a in the same manner as the sub tanks 61a to 61d. Except for this point, the printer has the same configuration as that of the printer according to the first embodiment. In FIG. 13, the same components as those in the first embodiment are denoted by the same reference numerals.

  In the first embodiment, when the main tank 71 is mounted on the mounting portion 70 when the sub tanks 61a to 61d are empty, the initial introduction is started. On the other hand, in the sixth embodiment, when the sub tanks 61a to 61d are in an empty state, the initial introduction is started when the empty main tank 71 is replenished with ink. The main tank 71 is replenished with ink by a user injecting ink from an ink replenishing hole provided in the main tank 71, and under the control of the control unit 100 from an ink cartridge detachably attached to the housing 1a. It may be realized by supplying ink to the tank 71.

  Also in the sixth embodiment, the same effects as in the first embodiment can be obtained with the same configuration as in the first embodiment.

  The preferred embodiments of the present invention have been described above. However, the present invention is not limited to the above-described embodiments, and various modifications can be made as long as they are described in the claims.

The liquid ejection device according to the first aspect of the present invention may be in a state where the main tank is not attached to the attachment portion. In addition, the liquid ejection device according to the first and second aspects of the present invention may be in a state where no liquid exists in the main space and / or the subspace.
The liquid is not limited to ink, and may be any liquid such as a treatment liquid that aggregates or deposits components in the ink.
The present invention is not limited to the serial method and can be applied to a line method.
The present invention is not limited to a printer but can be applied to a facsimile, a copier, and the like.
-The number of heads is arbitrary as long as it is plural.
-The number of sub-tanks is arbitrary as long as it is plural.
The plurality of sub tanks are not limited to being separated from each other, and may be integrally formed.
The plurality of sub-tanks are not limited to being arranged at positions completely overlapping when viewed from the vertical direction, but are partially overlapped when viewed from the vertical direction, positions adjacent to each other, positions separated from each other, Etc. may be arranged.
The vertical positional relationship between the main tank and the plurality of sub-tanks is arbitrary as long as each opening is in a positional relationship in which a supply form based on the weight of the liquid is realized. For example, the main tank and any or all of the plurality of sub tanks may overlap in the vertical direction, or the plurality of sub tanks may overlap in the vertical direction.
The main opening is preferably arranged at a position where the volume of the main space below the main opening is 70% or more of the total volume of the main space, but is not limited thereto.
The main outlet may be provided at an arbitrary position below the main opening, but from the viewpoint of using up the liquid stored in the main space, the main tank in the mounting portion is arranged in the first to fifth embodiments. It is preferable to be provided on the bottom surface of the wall that defines the space, and in the sixth embodiment, it is preferably provided on the bottom surface of the main tank.
The main outlet, the upstream inlet, and the upstream outlet may be located at the same height.
-The upstream inlet may be located at the same height as the main outlet.
-The downstream inlet may be located at the same height as the upstream outlet.
The intermediate inlet may be located at the same height as the upstream outlet.
-The upstream outlet may be located at the same height as the main outlet.
The intermediate outlet may be located at the same height as the upstream outlet.
The upstream opening may be located at the same height as the upstream outlet.
The intermediate opening may be located at the same height as the intermediate outlet.
-You may change suitably the magnitude relationship of distance Da-Dd and Da'-Dc '.
The upstream supply port and the downstream supply port are preferably arranged at a position where the volume of the corresponding subspace below the supply port is 30% or less of the total volume of the subspace, but is not limited thereto. .
-The magnitude relation of the resistance of each liquid flow path and the magnitude relation of the resistance of each gas flow path are both arbitrary.
-The 1st-3rd gas flow path may have a common part, and does not need to have a common part.
-Gas flow paths other than the first gas flow path may be omitted. Even in this case, the initial introduction can be realized without driving the drive source.
-Each gas permeable membrane may be omitted.
The vicinity of one end of the pipes 81, 91, and 95 may be fixed at a protruding position protruding from the wall 70a, or may be fixed at a retracted position retracted in the wall 70a. In the case where the vicinity of one end of the pipes 81, 91, 95 is fixed at the retracted position, the connecting portion connected to the pipes 81, 91, 95 in the main tank 71 may protrude from the outer wall of the main tank 71. Good. Alternatively, the vicinity of one end of the pipes 81, 91, and 95 is configured to be able to take the protruding position and the retracted position retracted in the wall 70a, and the control unit After 100 is detected, it may be moved from the retracted position to the protruding position under the control of the control unit 100. The vicinity of one end of each of the tubes 81, 91, and 95 may be attached to any one of the bottom surface, the side surface, and the top surface of the wall 70a.
-A control part does not need to perform the process of forced discharge based on the signal output from the downstream sensor.
In the above-described embodiment, the downstream sensor is configured to detect that the liquid level has reached the maximum water level (the height of the downstream opening), but is not limited thereto. It may be configured to detect that the height has reached a water level below the downstream opening. In this case, the control unit may perform forced discharge immediately after the detection or when a predetermined time has elapsed after the detection (when it is estimated that the liquid level has reached the maximum water level). . That is, the predetermined water level is not limited to the maximum water level, and may be a water level below the maximum water level.
In the above-described embodiment, the upstream sensor is configured to detect that the liquid level has reached the height of the upstream opening. However, the upstream sensor is not limited thereto. It may be configured to detect that the water level below the opening has been reached.
-An upstream sensor and a downstream sensor may be omitted.
-You may abbreviate | omit the valve provided in the mounting part or the main tank. As the valve 96 is omitted, the tube 95 may be omitted.

1: 301 inkjet printer (liquid ejection device)
6a Upstream sensor 6d Downstream sensor 51a First head 51b, 51c Third head 51d Second head 51x Discharge port 59a-59d Pump (forced discharge part)
61a Upstream sub tank 61b, 61c Intermediate sub tank 61d Downstream sub tank 62a Upstream sub space 62b, 62c Intermediate sub space 62d Downstream sub space 63a Upstream atmospheric communication port 63b, 63c Intermediate atmospheric communication port 63d Downstream atmospheric communication port 64a Upstream inlet 64b, 64c Intermediate inlet 64d Downstream inlet 65a Upstream outlet 65b, 65c Intermediate outlet 66a Upstream opening 66b, 66c Intermediate opening 66d Downstream opening 66ax Second gas permeable membrane 66bx, 66cx Third gas permeable membrane 66dx First gas permeable membrane 67a Upstream supply port 67d Downstream supply port 70 Mounting portion 71 Main tank 72 Main space 75 Main outlet 76 Main opening 76x Gas permeable membrane (main gas permeable membrane)
81x ink channel (first liquid channel)
82x to 84x; 384x ink flow path (second liquid flow path)
91a 2nd gas flow path 91b, 91c 3rd gas flow path 91d 1st gas flow path 96 Valve | bulb 100 Control part

Claims (21)

A first head having a plurality of first discharge ports for discharging liquid;
A second head having a plurality of second ejection ports for ejecting liquid;
A mounting portion to which a main tank having a main space for storing liquid is mounted, the main opening communicating with the main space when the main tank is mounted, and a position below the main opening And a mounting portion having a main outlet communicating with the main space when the main tank is mounted;
An upstream subspace for storing liquid, and an upstream atmospheric communication port for communicating the upstream subspace with the atmosphere, and the liquid stored in the upstream subspace is supplied to the first head An upstream sub-tank configured as
The main outlet extends to an upstream inlet that is at the same height as the main outlet or below the main outlet and communicates with the upstream subspace, and liquid is supplied from the main space to the upstream subspace. A first liquid flow path configured to:
A downstream subspace for storing liquid, and a downstream air communication port for communicating the downstream subspace with the atmosphere, and the liquid stored in the downstream subspace is supplied to the second head A downstream secondary tank, configured as follows:
From the upstream outlet located at the same height as the main outlet or below the main outlet and communicating with the upstream auxiliary space, located at the same height as the upstream outlet or below the upstream outlet and located at the downstream auxiliary A second liquid flow path extending to a downstream inlet communicating with the space and configured to supply liquid from the upstream subspace to the downstream subspace;
When the liquid level of the liquid in the downstream subspace extends below the downstream opening and extends from the downstream opening communicating with the downstream subspace to the main opening and below the downstream opening. A first gas flow path configured to communicate the main space with the atmosphere via the downstream opening and the main opening;
A liquid ejecting apparatus comprising: A first head having a plurality of first discharge ports for discharging liquid;
A second head having a plurality of second ejection ports for ejecting liquid;
A main tank having a main space for storing liquid;
An upstream subspace for storing liquid, and an upstream atmospheric communication port for communicating the upstream subspace with the atmosphere, and the liquid stored in the upstream subspace is supplied to the first head An upstream sub-tank configured as
Extending from the main outlet communicating with the main space to an upstream inlet located at the same height as the main outlet or below the main outlet and communicating with the upstream subspace, from the main space to the upstream subspace A first liquid channel configured to be supplied with a liquid;
A downstream subspace for storing liquid, and a downstream air communication port for communicating the downstream subspace with the atmosphere, and the liquid stored in the downstream subspace is supplied to the second head A downstream secondary tank, configured as follows:
From the upstream outlet located at the same height as the main outlet or below the main outlet and communicating with the upstream auxiliary space, located at the same height as the upstream outlet or below the upstream outlet and located at the downstream auxiliary A second liquid flow path extending to a downstream inlet communicating with the space and configured to supply liquid from the upstream subspace to the downstream subspace;
Extending from a downstream opening located below the upstream outlet and communicating with the downstream subspace to a main opening located above the main outlet and communicating with the main space, A first gas flow path configured to communicate the main space with the atmosphere through the downstream opening and the main opening when the liquid level is positioned below the downstream opening;
A liquid ejecting apparatus comprising:   An upstream opening located at the same height as the upstream outlet or below the upstream outlet and communicating with the upstream subspace extends to the main opening, and the liquid level of the liquid in the upstream subspace is the upstream The apparatus further comprises a second gas flow path configured to communicate the main space with the atmosphere via the upstream opening and the main opening when positioned below the opening. Item 3. The liquid ejection device according to Item 1 or 2.   The liquid ejection apparatus according to claim 3, wherein the first gas flow path and the second gas flow path have a common portion. A first gas permeable membrane provided in the downstream opening, wherein the first gas permeable membrane is configured to close the downstream opening and allow gas to pass therethrough and liquid not to pass through;
A second gas permeable membrane provided in the upstream opening, wherein the second gas permeable membrane is configured to close the upstream opening and allow gas to pass therethrough and liquid not to pass through;
The liquid ejection apparatus according to claim 3 or 4, further comprising:   The first gas channel and the second gas channel are configured such that the resistance of the first gas channel is smaller than the resistance of the second gas channel. The liquid ejection apparatus according to any one of 3 to 5. A third head having a plurality of third discharge ports for discharging liquid;
An intermediate subspace for storing the liquid supplied from the main space; and an intermediate atmospheric communication port for communicating the intermediate subspace with the atmosphere, and the liquid stored in the intermediate subspace is An intermediate sub tank configured to be supplied to the third head;
Further comprising
The second liquid flow path extends from the upstream outlet to an intermediate inlet located at the same height as the upstream outlet or below the upstream outlet and communicating with the intermediate subspace, from the upstream subspace. An upstream flow path configured to supply liquid to the intermediate subspace, and an intermediate outlet located at the same height as the upstream outlet or below the upstream outlet and communicating with the intermediate subspace, A downstream flow path that extends to the downstream inlet and is configured to supply liquid from the intermediate subspace to the downstream subspace. The liquid ejection device according to item.   The liquid ejection apparatus according to claim 7, wherein the first liquid channel is configured such that a resistance of the downstream channel is smaller than a resistance of the upstream channel.   The intermediate opening located at the same height as the intermediate outlet or below the intermediate outlet and communicating with the intermediate subspace extends to the main opening, and the liquid level of the liquid in the intermediate subspace is the intermediate The apparatus further comprises a third gas flow path configured to communicate the main space with the atmosphere via the intermediate opening and the main opening when positioned below the opening. Item 9. The liquid ejection device according to Item 7 or 8.   The liquid ejection apparatus according to claim 9, wherein the first gas channel, the second gas channel, and the third gas channel have a common portion. A first gas permeable membrane provided in the downstream opening, wherein the first gas permeable membrane is configured to close the downstream opening and allow gas to pass therethrough and liquid not to pass through;
A second gas permeable membrane provided in the upstream opening, wherein the second gas permeable membrane is configured to close the upstream opening and allow gas to pass therethrough and liquid not to pass through;
A third gas permeable membrane provided in the intermediate opening, wherein the third gas permeable membrane is configured to close the intermediate opening and allow gas to pass therethrough and liquid not to pass through;
The liquid discharging apparatus according to claim 9 or 10, further comprising:   The first gas channel, the second gas channel, and the third gas channel have a resistance of the third gas channel smaller than a resistance of the second gas channel, and the first gas 12. The liquid ejection device according to claim 9, wherein a flow path resistance is configured to be smaller than a resistance of the third gas flow path.   The vertical distance from the bottom of the downstream subspace to the downstream opening is greater than the vertical distance from the bottom of the upstream subspace to the upstream opening. The liquid ejection device according to claim 1.   The vertical distance from the bottom of the downstream subspace to the downstream opening is equal to the vertical distance from the bottom of the upstream subspace to the upstream outlet. The liquid ejection device according to one item. A downstream sensor configured to output a signal indicating a liquid level of the liquid in the downstream subspace; and
A forced discharge unit configured to forcibly discharge liquid from the plurality of first discharge ports and the plurality of second discharge ports;
Based on the signal output from the downstream sensor, when it is determined that the liquid level of the liquid in the downstream subspace has reached a predetermined water level, the forced discharge unit is controlled to control the plurality of first A controller for forcibly discharging liquid from the discharge port and the plurality of second discharge ports;
The liquid discharge apparatus according to claim 1, further comprising: A downstream sensor configured to output a signal indicating a liquid level of the liquid in the downstream subspace; and
An upstream sensor configured to output a signal indicating a liquid level of the liquid in the upstream subspace;
The liquid ejecting apparatus according to claim 1, further comprising:   A valve provided in the mounting portion or the main tank, wherein a blocking position for blocking communication between the main space and the atmosphere when a difference between the pressure in the main space and the pressure in the atmosphere is equal to or less than a predetermined value. The valve according to any one of claims 1 to 16, further comprising a valve configured to take a permission position for allowing the communication when the difference exceeds the predetermined value. Liquid discharge device.   The first liquid channel and the second liquid channel are configured such that the resistance of the second liquid channel is smaller than the resistance of the first liquid channel. The liquid ejection apparatus according to any one of 1 to 17.   A main gas permeable membrane provided in the main opening, further comprising a main gas permeable membrane configured to close the main opening, allow gas to permeate, and not allow liquid to permeate. The liquid ejection apparatus according to claim 1. The upstream sub tank has an upstream supply port for communicating the upstream sub space with the plurality of first discharge ports,
The liquid discharge according to any one of claims 1 to 19, wherein the downstream sub tank has a downstream supply port for communicating the downstream sub space with the plurality of second discharge ports. apparatus. The upstream supply port is located below the upstream outlet,
21. The liquid ejection apparatus according to claim 20, wherein the downstream supply port is located below the downstream opening.

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