Liquid dispensing device

Abstract

To provide a liquid discharge device which can suppress liquid consumption when discharging air bubbles.SOLUTION: A liquid discharge device comprises: a head 12 with a nozzle 13 that discharges a liquid supplied from a plurality of supply sources from the nozzle; a plurality of supply passages 17 connected to the plurality of supply sources and the head; a plurality of storage parts 20 which are positioned in the plurality of respective supply passages, and each have a storage chamber 34 for accumulating the liquid supplied from the plurality of supply sources; a plurality of discharge passages 21 which are connected to the plurality of respective storage parts, and discharge air bubbles from the plurality of respective storage chambers; and a suction part which applies negative pressure to the plurality of discharge passages. Each of the plurality of discharge passages has a resistance part 53 with a pressure loss larger than the corresponding supply passage.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a liquid ejection device. [Background technology]

[0002] Patent Document 1 describes a liquid ejection device that includes a plurality of storage sections for storing liquid, a head for ejecting the liquid stored in each of the storage sections, and a plurality of discharge flow paths extending from the storage sections. Patent Document 1 also describes that the storage sections are sucked through the plurality of discharge flow paths to eject air bubbles from the storage sections. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2010-179661 Summary of the Invention [Problem to be solved by the invention]

[0004] In such a liquid ejection device, there may be a difference in the amount of air bubbles in the multiple storage units. In this case, when the multiple storage units are suctioned, there is a risk that air bubbles will be discharged from one storage unit while liquid will be discharged from the other storage units. Therefore, there is a risk that liquid will be wasted from the storage units. [Means for solving the problem]

[0005] A liquid ejection device that solves the above problem comprises a head having a nozzle, the head ejecting liquid supplied from a plurality of supply sources from the nozzle; a plurality of supply flow paths connected to the plurality of supply sources and the head; a plurality of storage sections located in the plurality of supply flow paths, each having a storage chamber for storing liquid supplied from the plurality of supply sources; a plurality of discharge flow paths connected to the plurality of storage sections, each discharging bubbles from the plurality of storage chambers; and a suction section that applies negative pressure to the plurality of discharge flow paths, wherein the plurality of discharge flow paths each have a resistance section with a greater pressure loss than the corresponding supply flow path. [Brief explanation of the drawings]

[0006] [Figure 1] FIG. 1 is a schematic diagram illustrating an example of a liquid ejection device. [Figure 2] FIG. 2 is a schematic diagram showing a storage section, a discharge flow path, and a merging flow path. DETAILED DESCRIPTION OF THE INVENTION

[0007] An embodiment of a liquid ejection device will be described below with reference to the drawings. The liquid ejection device is, for example, an inkjet printer that prints images such as characters and photographs by ejecting ink, which is an example of a liquid, onto a medium such as paper or fabric.

[0008] <Overall configuration of liquid ejection device> As shown in Fig. 1, the liquid ejection device 11 includes a head 12. The head 12 is configured to eject a liquid. The head 12 has nozzles 13. The nozzles 13 eject the liquid. The head 12 prints an image on the medium 99 by ejecting the liquid from the nozzles 13 onto the medium 99.

[0009] The liquid ejection device 11 includes, for example, a carriage 14. The carriage 14 carries the head 12. The carriage 14 is configured to scan across the medium 99. Therefore, the liquid ejection device 11 of this example is a serial type printer. The liquid ejection device 11 may also be a line type printer that can eject liquid simultaneously across the width of the medium 99.

[0010] The liquid ejection device 11 includes a mounting portion 15. The mounting portion 15 is configured to accommodate a plurality of supply sources 16. For example, four supply sources 16 can be mounted to the mounting portion 15. The supply sources 16 are, for example, ink tanks or ink cartridges. For example, the four supply sources 16 each contain a different liquid. For example, the four supply sources 16 contain cyan ink, magenta ink, yellow ink, and black ink, respectively. Only one supply source 16 is shown in the drawings.

[0011] The liquid ejection device 11 includes a plurality of supply flow paths 17. The liquid ejection device 11 includes, for example, four supply flow paths 17. The plurality of supply flow paths 17 are flow paths for supplying liquid from a plurality of supply sources 16 to the head 12. The head 12 ejects the liquid supplied from the plurality of supply sources 16 from the nozzles 13.

[0012] The plurality of supply flow paths 17 are connected to the plurality of supply sources 16 and the head 12. The plurality of supply flow paths 17 are connected to the plurality of supply sources 16, respectively. The plurality of supply flow paths 17 are connected to the head 12. That is, one supply flow path 17 is connected to one supply source 16 and the head 12. The supply flow paths 17 extend from the mounting portion 15. The supply source 16 is mounted on the mounting portion 15, whereby the supply flow paths 17 are connected to the supply source 16.

[0013] The supply flow path 17 includes, for example, a first supply flow path 18 and a second supply flow path 19. The first supply flow path 18 is connected to the supply source 16. The second supply flow path 19 is connected to the head 12. In the supply flow path 17, the liquid flows in the order of the first supply flow path 18 and the second supply flow path 19. The first supply flow path 18 extends inside and outside the carriage 14. The second supply flow path 19 extends inside the carriage 14.

[0014] The liquid ejection device 11 includes a plurality of storage sections 20. The liquid ejection device 11 includes, for example, four storage sections 20. Only one storage section 20 is shown in the drawings. The plurality of storage sections 20 are located in the plurality of supply flow paths 17, respectively. That is, one storage section 20 is located in one supply flow path 17. The storage section 20 is located, for example, between the first supply flow path 18 and the second supply flow path 19. The storage section 20 is mounted, for example, on the carriage 14. The storage section 20 stores the liquid supplied from the supply source 16. The configuration of the storage section 20 will be described later.

[0015] The liquid ejection device 11 has a plurality of discharge flow paths 21. The liquid ejection device 11 has, for example, four discharge flow paths 21. In the drawings, only one discharge flow path 21 is shown. The plurality of discharge flow paths 21 extend from the plurality of storage units 20, respectively. That is, one discharge flow path 21 extends from one storage unit 20. The plurality of discharge flow paths 21 are mounted on, for example, a carriage 14.

[0016] The discharge flow path 21 is a flow path for discharging air bubbles within the storage portion 20. Air bubbles may be contained in the liquid supplied from the supply source 16 to the storage portion 20. As a result, the air bubbles tend to accumulate in the upper portion of the storage portion 20. The discharge flow path 21 is connected to, for example, the upper portion of the storage portion 20. The configuration of the discharge flow path 21 will be described later.

[0017] The liquid ejection device 11 may include a confluent flow path 22. The confluent flow path 22 is connected to a plurality of discharge flow paths 21. The confluent flow path 22 is connected to a plurality of discharge flow paths 21, thereby causing the plurality of discharge flow paths 21 to merge. The confluent flow path 22 is mounted on, for example, the carriage 14. The configuration of the confluent flow path 22 will be described later.

[0018] The liquid ejection device 11 may include an opening section 23. The opening section 23 is mounted on the carriage 14. The opening section 23 is configured to open the discharge flow path 21. For example, by opening the discharge flow path 21 with the opening section 23, it becomes possible for air bubbles to flow from the discharge flow path 21 to the joining flow path 22. The configuration of the opening section 23 will be described later.

[0019] The liquid ejection device 11 includes a maintenance unit 24. The maintenance unit 24 is a unit for performing maintenance on the liquid ejection device 11. The maintenance unit 24 has a suction unit 25. The suction unit 25 is, for example, a pump. Specifically, the suction unit 25 is a tube pump. The suction unit 25 is connected to, for example, the multiple discharge flow paths 21. In this example, the suction unit 25 is connected to the multiple discharge flow paths 21 by being connected to the confluence flow path 22. The suction unit 25 may also be directly connected to the multiple discharge flow paths 21, for example. In this example, the suction unit 25 is connected to the multiple discharge flow paths 21 by the carriage 14 moving to a predetermined position. The predetermined position will be described later. The suction unit 25 is connected to the multiple discharge flow paths 21 by, for example, the carriage 14 being positioned at a home position. The home position is, for example, a position where the carriage 14 is waiting when the head 12 is not ejecting liquid onto the medium 99. The suction unit 25 may be constantly connected to the multiple discharge flow paths 21. The suction unit 25 applies negative pressure to the multiple discharge flow paths 21 by suction. As a result, suction unit 25 sucks air bubbles accumulated in storage unit 20. As a result, air bubbles are discharged from storage unit 20.

[0020] The maintenance unit 24 may have a connection part 26. The connection part 26 is connected to the suction part 25. The connection part 26 can be connected to, for example, the confluent flow path 22. By connecting the connection part 26 to the confluent flow path 22, the suction part 25 is connected to the plurality of discharge flow paths 21. The suction part 25 applies negative pressure to the plurality of discharge flow paths 21 via the connection part 26, for example. The connection part 26 may be directly connected to the plurality of discharge flow paths 21. The connection part 26 may be constantly connected to the plurality of discharge flow paths 21.

[0021] The connection portion 26 is connected to the junction flow path 22, for example, when the carriage 14 moves to a predetermined position. Specifically, the connection portion 26 is connected to the junction flow path 22 while the carriage 14 is moving to the predetermined position. When the carriage 14 is located at the home position, the connection portion 26 is inserted into the junction flow path 22. At this time, the connection portion 26 is connected to the junction flow path 22. When the carriage 14 moves closer to the connection portion 26 from the home position, the connection portion 26 is further inserted into the junction flow path 22. The predetermined position is a position closer to the connection portion 26 than the home position. The carriage 14 passes through the home position while moving to the predetermined position. Therefore, the connection portion 26 is inserted into the junction flow path 22 while the carriage 14 is moving to the predetermined position.

[0022] The connecting portion 26 is connected to the junction flow path 22 by being inserted into the junction flow path 22. This eliminates the need to route the connecting portion 26 within the liquid ejection device 11 so that it follows the carriage 14, compared to when the connecting portion 26 is always connected to the junction flow path 22. This simplifies the configuration of the liquid ejection device 11.

[0023] The maintenance unit 24 may have a storage section 27. The storage section 27 is connected to the suction section 25. The air bubbles and liquid sucked by the suction section 25 are discharged into the storage section 27. The storage section 27 stores waste liquid generated by maintenance.

[0024] The maintenance unit 24 may have a cap 28. The cap 28 is configured to come into contact with the head 12. The cap 28 covers the nozzles 13 by coming into contact with the head 12. The act of the cap 28 coming into contact with the head 12 so as to cover the nozzles 13 is called capping. Capping forms a space in the cap 28 that communicates with the nozzles 13. Capping prevents the nozzles 13 from drying out.

[0025] The cap 28 is configured to be displaceable between a position in contact with the head 12 and a position in which it is not in contact with the head 12. The cap 28 is configured to be movable, for example, up and down. The cap 28 comes into contact with the head 12 by moving upward while facing the head 12. For example, the cap 28 can come into contact with the head 12 when the carriage 14 is located at the home position.

[0026] The cap 28 may be connected to the suction unit 25. In this case, the suction unit 25 suctions the inside of the discharge flow path 21 and the inside of the cap 28. More specifically, the suction unit 25 suctions the inside of the confluence flow path 22 and the inside of the cap 28.

[0027] The suction unit 25 sucks the inside of the cap 28, thereby sucking the liquid from the cap 28. For example, when the suction unit 25 sucks the inside of the cap 28 while the cap 28 is in a capping state, negative pressure inside the cap 28 acts on the nozzles 13. This causes thickened liquid, solidified liquid, and the like to be discharged from the nozzles 13. In other words, the maintenance unit 24 cleans the head 12. The liquid sucked from the cap 28 is stored in the storage unit 27.

[0028] The maintenance unit 24 may have a switching unit 29. The switching unit 29 is located in the maintenance unit 24 between the suction unit 25 and the connection unit 26, and between the suction unit 25 and the cap 28. That is, the suction unit 25 is connected to the connection unit 26 via the switching unit 29. The suction unit 25 is connected to the cap 28 via the switching unit 29.

[0029] The switching unit 29 is configured to switch the connection destination of the suction unit 25. That is, the switching unit 29 switches the connection destination of the suction unit 25 between the connection unit 26 and the cap 28, for example. The switching unit 29 is, for example, a switching valve. This allows the single suction unit 25 to apply negative pressure to both the discharge flow path 21 and the cap 28. That is, the configuration of the liquid discharge device 11 is simplified. The maintenance unit 24 may have a pump connected to the cap 28 in addition to the suction unit 25 connected to the discharge flow path 21.

[0030] The maintenance unit 24 has, for example, a starting portion 30. The starting portion 30 comes into contact with the opening portion 23. For example, when the carriage 14 is located at a predetermined position, the starting portion 30 comes into contact with the opening portion 23. Specifically, when the carriage 14 moves from the home position to a predetermined position, the starting portion 30 comes into contact with the opening portion 23. The starting portion 30 is, for example, a protrusion.

[0031] The starting unit 30 contacts the opening portion 23, thereby causing the opening portion 23 to open the discharge flow path 21. When the starting unit 30 contacts the opening portion 23, air bubbles can flow from the discharge flow path 21 to the merging flow path 22. In other words, the starting unit 30 initiates the removal of air bubbles from the storage unit 20. In this example, when the carriage 14 is not positioned at a predetermined position, the discharge flow path 21 is closed. This reduces the risk of liquid leaking from the discharge flow path 21 during printing or when waiting to print.

[0032] The liquid ejection device 11 may include a detection unit 31. The detection unit 31 is configured to detect the environmental temperature. The detection unit 31 is, for example, a temperature sensor. The environmental temperature is, for example, the temperature of the space in which the liquid ejection device 11 is installed, the temperature inside the liquid ejection device 11, etc.

[0033] The liquid ejection device 11 includes a control unit 32. The control unit 32 controls the liquid ejection device 11. The control unit 32 controls, for example, the head 12, the carriage 14, the maintenance unit 24, etc. The control unit 32 controls the suction unit 25. The control unit 32 controls the suction flow rate of the suction unit 25, for example, by controlling the rotation speed of the suction unit 25. The suction flow rate is, for example, the volume of fluid sucked per unit time. The larger the suction flow rate, the greater the negative pressure exerted by the suction unit 25.

[0034] The control unit 32 controls the suction flow rate of the suction unit 25 based on, for example, the environmental temperature detected by the detection unit 31. When the environmental temperature changes, the viscosity of the liquid changes. Specifically, the lower the environmental temperature, the greater the viscosity of the liquid. Therefore, the control unit 32 changes the suction flow rate of the suction unit 25 depending on the viscosity of the liquid.

[0035] The control unit 32 may be one or more processors that execute various processes according to a computer program. The control unit 32 may also be one or more dedicated hardware circuits, such as application specific integrated circuits, that execute at least some of the various processes. The control unit 32 may also be a circuit that includes a combination of the above processors and the above hardware circuits. The processor includes a CPU and memory, such as RAM and ROM. The memory stores program code or instructions configured to cause the CPU to execute processes. The memory, i.e., computer-readable medium, includes any readable medium that can be accessed by a general-purpose or special-purpose computer.

[0036] <Detailed configuration of the liquid ejection device> Next, the configurations of the reservoir 20, the discharge channel 21, the junction channel 22, and the open section 23 will be described.

[0037] First, a description will be given of the storage unit 20. Since the multiple storage units 20 each have the same configuration, only one storage unit 20 will be described here. 2, the reservoir 20 has a reservoir chamber 34. The reservoir chamber 34 communicates with the first supply flow path 18. The liquid supplied from the supply source 16 is stored in the reservoir chamber 34.

[0038] The reservoir 20 may include a filter chamber 35. The filter chamber 35 includes, for example, a first filter chamber 36 and a second filter chamber 37. The first filter chamber 36 is located upstream of the second filter chamber 37 in the direction in which the liquid flows from the supply source 16 toward the head 12. Therefore, in the filter chamber 35, the liquid flows from the first filter chamber 36 to the second filter chamber 37.

[0039] The filter chamber 35 is located upstream of the storage chamber 34. Therefore, in the storage section 20, the liquid flows through the filter chamber 35 and then the storage chamber 34. More specifically, the liquid flows through the first filter chamber 36, the second filter chamber 37, and then the storage chamber 34 in that order.

[0040] In this example, the first supply flow path 18 communicates with the first filter chamber 36. The second supply flow path 19 communicates with the storage chamber 34. Therefore, in this example, the storage chamber 34 communicates with the first supply flow path 18 via the filter chamber 35. The storage chamber 34 may also communicate directly with the first supply flow path 18.

[0041] The storage unit 20 has, for example, a storage body 38 and a flexible membrane 39. The storage body 38 is, for example, a resin case. The flexible membrane 39 is, for example, a flexible film. The storage unit 20 is configured to be able to store liquid by attaching the flexible membrane 39 to the storage body 38. The storage body 38 is connected to the first supply flow path 18 and the second supply flow path 19. The storage body 38 defines a storage chamber 34 and a filter chamber 35. The flexible membrane 39 defines the storage chamber 34. Therefore, the volume of the storage chamber 34 changes when the flexible membrane 39 is displaced.

[0042] Reservoir 38 has, for example, partition wall 40. Partition wall 40 is a wall that divides the interior of reservoir 20. Partition wall 40 divides the space within reservoir 20 into reservoir chamber 34 and filter chamber 35. Partition wall 40 has a through-hole 41 that connects reservoir chamber 34 and filter chamber 35.

[0043] The reservoir 38 has, for example, a separation wall 42. The separation wall 42 is a wall that divides the filter chamber 35 into a first filter chamber 36 and a second filter chamber 37. The separation wall 42 has an attachment hole 43 that allows the first filter chamber 36 and the second filter chamber 37 to communicate with each other.

[0044] The reservoir 20 has, for example, a filter 44. The filter 44 is located in the filter chamber 35. The filter 44 is attached to the reservoir body 38. The filter 44 is attached to the separation wall 42. The filter 44 is fitted into, for example, a mounting hole 43. The liquid flows from the first filter chamber 36 to the second filter chamber 37 by passing through the filter 44. As the liquid passes through the filter 44, foreign matter is removed from the liquid.

[0045] The reservoir 20 may have an adjustment valve 45. The adjustment valve 45 opens and closes the supply flow path 17. When the adjustment valve 45 is opened, the liquid flows from the first supply flow path 18 to the second supply flow path 19 through the reservoir 20.

[0046] The adjustment valve 45 is a valve that adjusts the pressure inside the head 12. The adjustment valve 45 adjusts the pressure inside the head 12 by adjusting the pressure in the storage chamber 34. The adjustment valve 45 opens the supply flow path 17 when the pressure inside the head 12 falls below a predetermined pressure. The adjustment valve 45 adjusts the pressure in the storage chamber 34 so that the pressure inside the head 12 becomes a predetermined negative pressure. The adjustment valve 45 has, for example, an adjustment valve body 46 and an adjustment spring 47.

[0047] The adjusting valve body 46 has, for example, a shaft portion 48 and a plate portion 49. The shaft portion 48 is inserted into the through-hole 41. The plate portion 49 is located at one end of the shaft portion 48. The plate portion 49 is located in the second filter chamber 37. The other end of the shaft portion 48 is located in the storage chamber 34. Therefore, the adjusting valve body 46 is located across the storage chamber 34 and the second filter chamber 37. The other end of the shaft portion 48 contacts the flexible membrane 39. A contact plate 50 that contacts the other end of the shaft portion 48 may be attached to the flexible membrane 39.

[0048] The adjustment spring 47 is located in the second filter chamber 37. The adjustment spring 47 contacts, for example, the separation wall 42 and the plate portion 49. The adjustment spring 47 presses the plate portion 49 toward the partition wall 40. The plate portion 49 contacts the partition wall 40, thereby closing the through-hole 41.

[0049] When the pressure in the storage chamber 34 decreases, the flexible membrane 39 is displaced so as to approach the partition wall 40. For example, when the pressure in the storage chamber 34 decreases due to the head 12 discharging liquid, the flexible membrane 39 is displaced so as to reduce the volume of the storage chamber 34. As a result, the flexible membrane 39 presses the adjustment valve body 46 toward the adjustment spring 47.

[0050] When the force with which the flexible membrane 39 presses the regulating valve body 46 exceeds the force with which the regulating spring 47 presses the regulating valve body 46, the plate portion 49 moves away from the partition wall 40. When the plate portion 49 moves away from the partition wall 40, the through-hole 41 opens. This allows liquid to flow from the second filter chamber 37 to the storage chamber 34. When liquid flows into the storage chamber 34, the pressure inside the storage chamber 34 increases. When the pressure inside the storage chamber 34 increases, the flexible membrane 39 is displaced away from the partition wall 40. As a result, the plate portion 49 comes into contact with the partition wall 40. In this way, the regulating valve 45 regulates the pressure in the storage chamber 34 to a predetermined negative pressure.

[0051] Next, a description will be given of the discharge flow path 21. Since the plurality of discharge flow paths 21 each have the same configuration, one discharge flow path 21 will be described here. The discharge flow path 21 has, for example, a first discharge flow path 51 and a second discharge flow path 52. The first discharge flow path 51 and the second discharge flow path 52 are connected to the reservoir 38. The first discharge flow path 51 is a flow path that communicates with the reservoir chamber 34. The first discharge flow path 51 communicates with, for example, an upper portion of the reservoir chamber 34. The second discharge flow path 52 is a flow path that communicates with the filter chamber 35. More specifically, the second discharge flow path 52 communicates with the first filter chamber 36. The second discharge flow path 52 communicates with, for example, an upper portion of the first filter chamber 36.

[0052] The first discharge flow path 51 is a flow path that discharges air bubbles that accumulate in the storage chamber 34. The second discharge flow path 52 is a flow path that discharges air bubbles that accumulate in the filter chamber 35. More specifically, the second discharge flow path 52 is a flow path that discharges air bubbles that accumulate in the first filter chamber 36.

[0053] The first discharge flow path 51 and the second discharge flow path 52 each have a resistance portion 53. That is, one discharge flow path 21 has two resistance portions 53. The resistance portions 53 are portions configured to increase flow path resistance when liquid flows in the first discharge flow path 51 and the second discharge flow path 52. That is, the resistance portions 53 are portions where pressure loss increases when liquid flows.

[0054] Resistance section 53 is a section configured to cause a larger pressure loss in discharge flow path 21 than in supply flow path 17. More specifically, resistance section 53 is a section configured to cause a larger pressure loss in discharge flow path 21 than in first supply flow path 18. As a result, in one storage section 20, the pressure loss is larger when liquid flows through discharge flow path 21 connected to that storage section 20 than when liquid flows through supply flow path 17 connected to that storage section 20. Therefore, in one storage section 20, it is more difficult for liquid to flow through discharge flow path 21 than through supply flow path 17.

[0055] The resistance portion 53 is formed, for example, by a portion of the discharge flow path 21 where the flow path cross-sectional area is small. That is, the resistance portion 53 is formed by narrowing the discharge flow path 21. Therefore, the flow path diameter of the resistance portion 53 is smaller than the flow path diameter of the supply flow path 17. The resistance portion 53 may be formed, for example, by a bent portion of the discharge flow path 21. The resistance portion 53 may be formed, for example, by increasing the flow path length of the discharge flow path 21. The discharge flow path 21 may be configured so that it is more difficult for liquid to flow through it than the supply flow path 17.

[0056] The discharge flow path 21 has a plurality of containers and a plurality of on-off valves. More specifically, one discharge flow path 21 has two containers. One discharge flow path 21 has two on-off valves. The first discharge flow path 51 has a first container 54 and a first on-off valve 55. The second discharge flow path 52 has a second container 56 and a second on-off valve 57. The first container 54 and the second container 56 have the same configuration. The first on-off valve 55 and the second on-off valve 57 have the same configuration.

[0057] The first container 54 is located in the first discharge flow path 51. The first container 54 houses a first on-off valve 55. The first container 54 constitutes an end of the first discharge flow path 51. The first container 54 is connected to the merging flow path 22. The first container 54 has a first opening plate 59 in which a first connection port 58 opens. The first connection port 58 connects the inside of the first container 54 to the inside of the merging flow path 22. In other words, the first connection port 58 connects the inside of the first discharge flow path 51 to the inside of the merging flow path 22.

[0058] The first on-off valve 55 is an on-off valve included in the first discharge flow path 51. The first on-off valve 55 opens and closes the first discharge flow path 51. The first on-off valve 55 normally closes the first discharge flow path 51. Therefore, the first discharge flow path 51 is normally closed to the merging flow path 22. The first on-off valve 55 includes a first on-off valve body 60 and a first on-off spring 61. The first on-off valve body 60 and the first on-off spring 61 are housed in the first housing body 54. The first on-off valve 55 is opened by the opening portion 23.

[0059] The first on-off valve body 60 has, for example, a first shaft portion 62 and a first plate portion 63. The first shaft portion 62 is inserted into the first connection port 58. The first plate portion 63 is located at one end of the first shaft portion 62. The first plate portion 63 is located within the first housing 54. The other end of the first shaft portion 62 is located within the merging flow path 22. Therefore, the first on-off valve body 60 is located across the first housing 54 and the merging flow path 22.

[0060] The first opening / closing spring 61 is located within the first housing 54. The first opening / closing spring 61 contacts the first plate portion 63. The first opening / closing spring 61 presses the first opening / closing valve body 60 toward the junction flow path 22. The first opening / closing spring 61 presses the first plate portion 63 toward the first opening plate 59. The first plate portion 63 contacts the first opening plate 59, thereby blocking the first connection port 58. This closes the first discharge flow path 51.

[0061] The second housing 56 is located in the second discharge flow path 52. The second housing 56 houses a second on-off valve 57. The second housing 56 constitutes an end of the second discharge flow path 52. The second housing 56 is connected to the merging flow path 22. The second housing 56 has a second opening plate 65 in which a second connection port 64 opens. The second connection port 64 connects the inside of the second housing 56 to the inside of the merging flow path 22. In other words, the second connection port 64 connects the inside of the second discharge flow path 52 to the inside of the merging flow path 22.

[0062] The second on-off valve 57 is an on-off valve included in the second discharge flow path 52. The second on-off valve 57 opens and closes the second discharge flow path 52. The second on-off valve 57 normally closes the second discharge flow path 52. Therefore, the second discharge flow path 52 is normally closed to the merging flow path 22. The second on-off valve 57 includes a second on-off valve body 66 and a second on-off spring 67. The second on-off valve body 66 and the second on-off spring 67 are housed in the second housing 56. The second on-off valve 57 is opened by the opening portion 23.

[0063] The second on-off valve body 66 has, for example, a second shaft portion 68 and a second plate portion 69. The second shaft portion 68 is inserted into the second connection port 64. The second plate portion 69 is located at one end of the second shaft portion 68. The second plate portion 69 is located within the second housing 56. The other end of the second shaft portion 68 is located within the merging flow path 22. Therefore, the second on-off valve body 66 is located across the second housing 56 and the merging flow path 22.

[0064] The second opening / closing spring 67 is located in the second housing 56. The second opening / closing spring 67 contacts the second plate portion 69. The second opening / closing spring 67 presses the second opening / closing valve body 66 toward the junction flow path 22. The second opening / closing spring 67 presses the second plate portion 69 toward the second opening plate 65. The second plate portion 69 contacts the second opening plate 65, thereby blocking the second connection port 64. This closes the second discharge flow path 52.

[0065] Next, the confluence flow path 22 will be described. The confluence flow path 22 has a confluence section 71. A plurality of containers are connected to the confluence section 71. A plurality of first containers 54 and a plurality of second containers 56 are connected to the confluence section 71. That is, a plurality of first discharge flow paths 51 and a plurality of second discharge flow paths 52 are connected to the confluence section 71. Bubbles, liquid, etc. flow into the confluence section 71 through the discharge flow paths 21. The confluence section 71 has a confluence 72 and a flexible membrane 73.

[0066] The combined fluid 72 is connected to a plurality of containers. The combined fluid 72 is, for example, a resin case. The flexible membrane 73 is attached to the combined fluid 72. The flexible membrane 73 is, for example, a flexible film. The volume of the confluence section 71 changes as the flexible membrane 73 is displaced.

[0067] The confluence flow path 22 has a plurality of operating plates. The confluence flow path 22 has, for example, two operating plates. Specifically, the confluence flow path 22 has a first operating plate 74 and a second operating plate 75. The first operating plate 74 and the second operating plate 75 are located within the confluence section 71.

[0068] The first operating plate 74 is capable of contacting the plurality of first on-off valve bodies 60. Specifically, the first operating plate 74 is capable of contacting the plurality of first shaft portions 62. In this example, the first operating plate 74 is capable of contacting each of the four first shaft portions 62. The second operating plate 75 is capable of contacting the plurality of second on-off valve bodies 66. Specifically, the second operating plate 75 is capable of contacting the plurality of second shaft portions 68. In this example, the second operating plate 75 is capable of contacting the four second shaft portions 68.

[0069] When the first operating plate 74 approaches the first housing 54, the first on-off valve body 60 is pushed by the first operating plate 74. As the first on-off valve body 60 is pushed by the first operating plate 74, the first plate portion 63 moves away from the first opening plate 59. In this way, the first operating plate 74 simultaneously opens the multiple first discharge flow paths 51.

[0070] When the second operating plate 75 approaches the second housing 56, the second opening / closing valve body 66 is pushed by the second operating plate 75. As the second opening / closing valve body 66 is pushed by the second operating plate 75, the second plate portion 69 moves away from the second opening plate 65. In this way, the second operating plate 75 simultaneously opens the plurality of second discharge flow paths 52.

[0071] The confluent flow path 22 has an insertion portion 76. The connection portion 26 is inserted into the insertion portion 76. By inserting the connection portion 26 into the insertion portion 76, the confluent flow path 22 and the suction portion 25 are connected. In other words, by inserting the connection portion 26 into the insertion portion 76, the plurality of discharge flow paths 21 and the suction portion 25 are connected. The insertion portion 76 has an insert 77, a valve portion 78, and a seal portion 79.

[0072] The insert 77 is connected to the combined fluid 72. The inside of the insert 77 is connected to the inside of the combined fluid 72. The air bubbles and liquid that have flowed into the combined fluid 72 flow into the insert 77. A connection port 80 opens in the insert 77. The connection part 26 is inserted into the connection port 80.

[0073] The valve portion 78 is located in the insert 77. The valve portion 78 opens and closes the confluent flow path 22. The valve portion 78 normally blocks the connection port 80. The confluent flow path 22 is closed by the valve portion 78. The valve portion 78 opens the confluent flow path 22 when the connection portion 26 is inserted into the insert 77. The valve portion 78 moves away from the connection port 80, for example, by being pushed by the connection portion 26 inserted into the insert 77. This opens the confluent flow path 22.

[0074] The seal portion 79 is attached to the insert 77. The seal portion 79 is located at the connection port 80. When the connection portion 26 is inserted into the connection port 80, the seal portion 79 seals the connection portion 26 and the insert 77 together. For example, when the connection portion 26 is inserted into the insert 76, the seal portion 79 comes into close contact with the outer peripheral surface of the connection portion 26. In this way, the seal portion 79 seals the connection portion 26 and the insert 77 together. This reduces the risk of liquid leaking from the connection port 80.

[0075] When the suction unit 25 applies negative pressure to the multiple discharge flow paths 21, the carriage 14 moves to the home position. At this time, as the carriage 14 moves, the connection unit 26 first comes into contact with the seal unit 79. As the carriage 14 moves further, the connection unit 26 comes into contact with the valve unit 78 while still in contact with the seal unit 79. As the carriage 14 moves further, the connection unit 26 is inserted into the insertion unit 76.

[0076] When applying negative pressure to the multiple discharge channels 21, the suction unit 25 is driven, for example, with the seal 79 in close contact with the connection 26 and the valve 78 closing the confluent channel 22. For example, the control unit 32 starts driving the suction unit 25 before the connection 26 is inserted into the insertion section 76. After the negative pressure in the suction unit 25 reaches a predetermined pressure, the carriage 14 moves so that the connection 26 is inserted into the insertion section 76, thereby opening the confluent channel 22. This makes it less likely that air will flow back into the confluent channel 22 than when the suction unit 25 starts driving after the connection 26 is inserted into the insertion section 76. In other words, the risk of air flowing into the confluent channel 22 through the connection port 80 is reduced.

[0077] Next, the open portion 23 will be described. The opening section 23 has a plurality of opening members. The opening section 23 has, for example, a first opening member 81 and a second opening member 82. The first opening member 81 is a member that opens the first discharge flow path 51. The second opening member 82 is a member that opens the second discharge flow path 52.

[0078] The first opening member 81 can move toward and away from the merging flow path 22. When the first opening member 81 approaches the merging flow path 22, it comes into contact with the first operating plate 74 through the flexible membrane 73. When the first opening member 81 approaches the merging flow path 22, it presses the first operating plate 74 toward the first discharge flow path 51. This causes the multiple first discharge flow paths 51 to be opened simultaneously.

[0079] The second opening member 82 can move toward and away from the merging flow path 22. When the second opening member 82 approaches the merging flow path 22, it comes into contact with the second operating plate 75 through the flexible membrane 73. When the second opening member 82 approaches the merging flow path 22, it presses the second operating plate 75 toward the second discharge flow path 52. This causes the multiple second discharge flow paths 52 to be opened simultaneously.

[0080] The opening portion 23 has an interlocking portion 83. When the starting portion 30 comes into contact with the interlocking portion 83, the interlocking portion 83 operates one of the first opening member 81 and the second opening member 82. The interlocking portion 83 is configured to be switchable between the first opening member 81 and the second opening member 82. For example, the control unit 32 switches the interlocking portion 83 between the first opening member 81 and the second opening member 82. When the starting unit 30 comes into contact with the interlocking portion 83 while the interlocking portion 83 is interlocked with the first opening member 81, the interlocking portion 83 is displaced, causing the first opening member 81 to approach the junction flow path 22. When the starting unit 30 comes into contact with the interlocking portion 83 while the interlocking portion 83 is interlocked with the second opening member 82, the interlocking portion 83 is displaced, causing the second opening member 82 to approach the junction flow path 22. When the starting unit 30 comes into contact with the interlocking portion 83, the multiple first discharge flow paths 51 or the multiple second discharge flow paths 52 are opened. In this example, either the first opening member 81 or the second opening member 82 is interlocked with the interlocking portion 83, so that the first discharge flow paths 51 and the second discharge flow paths 52 are not both opened at the same time. Therefore, the first opening / closing valve 55 and the second opening / closing valve 57 are opened and closed individually in association with the movement of the carriage 14. This allows air bubbles to be sucked into the storage chamber 34 and the filter chamber 35 individually.

[0081] <Air bubble suction> Next, the suction of air bubbles will be described. There may be a bias in the amount of bubbles among the multiple storage sections 20. In this case, when suction section 25 applies negative pressure to the multiple storage sections 20, there is a risk that bubbles will be sucked from one storage section 20 while liquid will be sucked from the other storage sections 20. In other words, there is a risk that liquid will be wasted.

[0082] The first discharge flow path 51 and the second discharge flow path 52 each have a resistance portion 53. The resistance portion 53 causes a difference in pressure loss between when a liquid flows through the discharge flow path 21 and when air bubbles flow through the discharge flow path 21. When air bubbles flow through the discharge flow path 21, the pressure loss is smaller than when a liquid flows through the discharge flow path 21. Therefore, the negative pressure from the suction portion 25 acts intensively on the discharge flow path 21 through which the air bubbles flow. This makes it difficult for liquid to flow from the storage portion 20 that does not contain air bubbles. As a result, air bubbles are preferentially sucked from the storage portion 20 containing air bubbles among the multiple storage portions 20.

[0083] To preferentially suck in air bubbles, it is necessary to increase the pressure loss in discharge flow path 21 through which the liquid flows. Therefore, it is preferable that the suction flow rate by suction unit 25 is large. On the other hand, if the suction flow rate by suction unit 25 is too large, the pressure inside storage unit 20 may become smaller than necessary, which may cause air to flow from nozzle 13 into head 12. Therefore, to preferentially suck in air bubbles, it is preferable that the suction flow rate by suction unit 25 is large enough to prevent air from being sucked from nozzle 13.

[0084] Because the storage chamber 34 is connected to the inside of the head 12, when air bubbles are sucked from the storage chamber 34 through the first discharge flow path 51, there is a high risk of air flowing into the head 12 from the nozzle 13. On the other hand, because the filter chamber 35 is not connected to the head 12, there is a low risk of air flowing into the head 12 from the nozzle 13 when air bubbles are sucked from the filter chamber 35 through the second discharge flow path 52. However, there is a risk of the adjustment valve 45 opening unexpectedly, for example, if another component interferes with the adjustment valve 45. Therefore, even when air bubbles are sucked from the filter chamber 35 through the second discharge flow path 52, it is preferable that the suction flow rate by the suction unit 25 is large enough to avoid sucking air through the nozzle 13.

[0085] The viscosity of ink changes depending on the ambient temperature. The lower the ambient temperature, the greater the viscosity of the ink. When the viscosity of the ink increases, it becomes more difficult for the ink to flow through the discharge flow path 21. In other words, when the ambient temperature is low, the difference in pressure loss between the discharge flow path 21 through which air bubbles flow and the discharge flow path 21 through which liquid flows becomes greater. Therefore, when the ambient temperature is low, the pressure inside the storage unit 20 is likely to become lower than necessary. In response to this, the control unit 32 reduces the suction flow rate by the suction unit 25 when the ambient temperature is low compared to when the ambient temperature is high. This reduces the risk of the pressure inside the storage unit 20 becoming lower than necessary.

[0086] For example, when the environmental temperature detected by the detection unit 31 is low, the control unit 32 reduces the suction flow rate of the suction unit 25 compared to when the environmental temperature is high. For example, when the environmental temperature is low, the control unit 32 reduces the rotation speed of the suction unit 25 compared to when the environmental temperature is high.

[0087] <Suction flow rate by suction unit> Next, an example of a method for determining the suction flow rate by the suction unit 25 will be described. When air bubbles have accumulated in only one of the multiple storage sections 20 and the suction section 25 performs suction, the negative pressure from the suction section 25 is concentrated in that storage section 20. Therefore, when air bubbles have accumulated in only one of the multiple storage sections 20, the pressure inside that storage section 20 drops the most. Therefore, here we consider a case where air bubbles have accumulated in only the storage section 20 that stores black ink out of the four storage sections 20. In determining the suction flow rate by the suction section 25, the following variables are defined.

[0088]

number

[0089] When the pressure loss in the supply flow path 17 and the pressure loss in the discharge flow path 21 are expressed as the product of the proportionality coefficient, the ink viscosity, and the suction flow rate, the internal pressure of the four filter chambers 35 can be expressed as follows:

[0090]

number

[0091]

number

[0092]

number

[0093]

number

[0094]

number

[0095]

number

[0096]

number

[0097] Next, the case where the reservoir chamber 34 is suctioned will be considered. The internal pressure of each of the four storage chambers 34 is adjusted by the adjustment valve 45 so as to be equal to the operating pressure of the adjustment valve 45. The operating pressure of the adjustment valve 45 is the pressure in the storage chamber 34 when the adjustment valve 45 opens. Therefore, the internal pressure of each of the four storage chambers 34 can be expressed as follows:

[0098]

number

[0099]

number

[0100]

number

[0101]

number

[0102]

number

[0103]

number

[0104]

number

[0105] <Effects of the liquid ejection device> Next, the effects of the above embodiment will be described. (1) The plurality of discharge flow paths 21 each have a resistance portion 53 that causes a larger pressure loss than the corresponding supply flow paths 17. When there is a bias in the amount of bubbles among the plurality of storage portions 20, for example, bubbles may be sucked from one storage portion 20 while liquid may be sucked from another storage portion 20. In this case, according to the above configuration, the resistance portion 53 makes it difficult for liquid to flow through the discharge flow paths 21, so that bubbles preferentially flow through the discharge flow paths 21 in the plurality of storage portions 20. This reduces the amount of liquid sucked from the storage portions 20. Therefore, consumption of liquid when discharging bubbles is suppressed.

[0106] (2) The carriage 14 moves to a predetermined position, whereby the connection portion 26 is connected to the confluent flow path 22. The suction portion 25 applies a negative pressure to the plurality of discharge flow paths 21 via the connection portion 26.

[0107] According to the above configuration, the configuration is simpler than when the suction unit 25 is constantly connected to the discharge flow path 21. When the suction unit 25 is constantly connected to the discharge flow path 21, it becomes necessary to connect the suction unit 25 and the discharge flow path 21 with a flow path that can follow the movement of the carriage 14, for example.

[0108] (3) The first on-off valve 55 and the second on-off valve 57 are opened and closed individually in conjunction with the movement of the carriage 14. According to the above configuration, when first on-off valve 55 is opened, air bubbles accumulated in storage chamber 34 are discharged through first discharge flow path 51. When second on-off valve 57 is opened, air bubbles accumulated in filter chamber 35 are discharged through second discharge flow path 52. Therefore, air bubbles can be discharged from storage chamber 34 and filter chamber 35 separately.

[0109] (4) The suction unit 25 is driven with the seal 79 in close contact with the connection unit 26 and with the valve 78 closing the confluent flow path 22. After the negative pressure in the suction unit 25 reaches a predetermined pressure, the carriage 14 moves so that the connection unit 26 is inserted into the insertion unit 76, thereby opening the confluent flow path 22. This configuration reduces the risk of air backflowing into the confluent flow path 22 compared to when the suction unit 25 starts to operate after the connection unit 26 is inserted into the insertion unit 76.

[0110] (5) The liquid ejection device 11 includes a cap 28 that contacts the head 12 so as to cover the nozzles 13, and is connected to the suction unit 25. The liquid ejection device 11 includes a switching unit 29 that switches the connection destination of the suction unit 25 between the connection unit 26 and the cap 28.

[0111] According to the above configuration, the connection part 26 and the cap 28 can be sucked by one suction part 25. Therefore, the configuration of the liquid discharger 11 is simpler than when a suction part 25 that sucks the inside of the cap 28 is provided separately from a suction part 25 that sucks the discharge flow path 21.

[0112] (6) When the environmental temperature detected by the detection unit 31 is low, the control unit 32 reduces the suction flow rate of the suction unit 25 compared to when the environmental temperature is high. If the suction flow rate by suction unit 25 is large, there is a risk that air will be drawn into head 12 from nozzle 13 when air bubbles are drawn from storage unit 20. If the suction flow rate by suction unit 25 is small, the pressure loss in discharge flow path 21 through which the liquid flows will be small, and therefore, while air bubbles will be drawn from one storage unit 20, liquid may be drawn from another storage unit 20. Therefore, it is preferable that the suction flow rate by suction unit 25 is large enough to prevent air from being drawn into head 12 from nozzle 13.

[0113] The viscosity of the liquid changes depending on the ambient temperature. When the viscosity of the liquid changes, the pressure loss in the discharge flow path 21 through which the liquid flows changes. For example, when the ambient temperature drops, the viscosity of the liquid increases, and the pressure loss in the discharge flow path 21 through which the liquid flows increases. In this case, the liquid becomes harder to suck in, while the pressure in the reservoir 20 to which the discharge flow path 21 through which the air bubbles flow is connected tends to become lower than necessary. Therefore, when the ambient temperature is low, there is a greater risk of air being drawn into the head 12 from the nozzle 13.

[0114] According to the above configuration, when the ambient temperature is low, the suction flow rate by the suction unit 25 is reduced, thereby reducing the pressure loss in the discharge flow path 21 through which the liquid flows, compared to when the ambient temperature is high. This prevents the pressure in the reservoir 20, to which the discharge flow path 21 through which the bubbles flow is connected, from becoming lower than necessary. This reduces the risk of air being drawn into the head 12 from the nozzle 13.

[0115] (7) The adjusting valve 45 opens the supply passage 17 when the pressure inside the head 12 falls below a predetermined pressure. According to the above configuration, the pressure inside the head 12 is adjusted by the adjusting valve 45. This allows the head 12 to eject liquid appropriately.

[0116] <Example of modification of liquid ejection device> This embodiment can be implemented with the following modifications: This embodiment and the following modifications can be implemented in combination with each other within the scope of technical compatibility.

[0117] The control unit 32 may change the time for which the suction unit 25 applies negative pressure to the plurality of discharge flow paths 21 depending on the length of the left-standing time. For example, the control unit 32 may increase the time for which the suction unit 25 applies negative pressure to the plurality of discharge flow paths 21 as the left-standing time increases. The left-standing time may be, for example, the time that has elapsed since the power of the liquid discharge device 11 was switched off. The left-standing time may be, for example, the time that has elapsed since the previous air bubble suction.

[0118] The liquid ejected by the head 12 is not limited to ink, but may be a liquid in which particles of a functional material are dispersed or mixed in a liquid. For example, the head 12 may eject a liquid containing dispersed or dissolved materials such as electrode materials or pixel materials used in the manufacture of liquid crystal displays, electroluminescent displays, and surface-emitting displays.

[0119] <Technical Concept of the Liquid Ejection Device> The technical concepts and effects that can be understood from the above-described embodiment and modified examples will be described below.

[0120] (A) A liquid ejection device includes a head having a nozzle, the head ejecting liquid supplied from a plurality of supply sources from the nozzle; a plurality of supply flow paths connected to the plurality of supply sources and the head; a plurality of storage sections located in the plurality of supply flow paths, each having a storage chamber for storing liquid supplied from the plurality of supply sources; a plurality of discharge flow paths connected to the plurality of storage sections, each discharging bubbles from the plurality of storage chambers; and a suction section that applies negative pressure to the plurality of discharge flow paths, wherein the plurality of discharge flow paths each have a resistance section with a greater pressure loss than the corresponding supply flow path.

[0121] If there is a difference in the amount of bubbles among the multiple storage units, for example, bubbles may be sucked from one storage unit while liquid is sucked from another storage unit. In this case, with the above configuration, the resistance makes it difficult for liquid to flow through the discharge flow path, so bubbles preferentially flow through the discharge flow path in the multiple storage units. This reduces the amount of liquid sucked from the storage units. Therefore, liquid consumption is suppressed when discharging bubbles.

[0122] (B) The liquid ejection device may include a carriage carrying the head and a plurality of the storage sections, the carriage scanning the medium, a confluence flow path connected to the plurality of discharge flow paths, and a connection section connectable to the confluence flow path, wherein the connection section is connected to the confluence flow path when the carriage moves to a predetermined position, and the suction section applies negative pressure to the plurality of discharge flow paths via the connection section.

[0123] According to the above configuration, the configuration is simpler than when the suction unit is constantly connected to the discharge flow path, which requires, for example, a flow path that can follow the movement of the carriage to connect the suction unit and the discharge flow path.

[0124] (C) In the above liquid ejection device, the discharge flow path has a plurality of on-off valves, the storage section has a filter that collects foreign matter and a filter chamber located upstream of the storage chamber in which the filter is located, the discharge flow path has a first discharge flow path that communicates with the storage chamber and a second discharge flow path that communicates with the filter chamber, the plurality of on-off valves include a first on-off valve in the first discharge flow path and a second on-off valve in the second discharge flow path, and the first on-off valve and the second on-off valve may be opened and closed individually in conjunction with the movement of the carriage.

[0125] According to the above configuration, when the first on-off valve is opened, air bubbles accumulated in the storage chamber are discharged through the first discharge flow path. When the second on-off valve is opened, air bubbles accumulated in the filter chamber are discharged through the second discharge flow path. Therefore, air bubbles can be discharged separately from the storage chamber and the filter chamber.

[0126] (D) In ​​the above liquid ejection device, the confluent flow path may have an insertion portion into which the connecting portion is inserted, the insertion portion having a seal portion that fits tightly around the outer periphery of the connecting portion when the connecting portion is inserted, and a valve portion that opens the confluent flow path when the connecting portion is inserted, the suction portion is driven with the seal portion in tight contact with the connecting portion and the confluent flow path closed by the valve portion, and the carriage may open the confluent flow path by moving so that the connecting portion is inserted into the insertion portion after the negative pressure in the suction portion reaches a predetermined pressure. With the above configuration, the risk of air flowing back into the confluent flow path is reduced compared to when the suction portion starts driving after the connecting portion is inserted into the insertion portion.

[0127] (E) The liquid ejection device may include a cap that contacts the head so as to cover the nozzle, the cap being connected to the suction unit, and a switching unit that switches the connection destination of the suction unit between the connection unit and the cap.

[0128] According to the above configuration, the connection part and the cap can be sucked by a single suction part, which simplifies the configuration of the liquid ejection device compared to a case where a suction part that sucks the inside of the cap is provided separately from a suction part that sucks the discharge flow path.

[0129] (F) The liquid ejection device may include a detection unit that detects the ambient temperature and a control unit that controls the suction unit, and the control unit may reduce the suction flow rate by the suction unit when the ambient temperature detected by the detection unit is low compared to when the ambient temperature is high.

[0130] If the suction flow rate by the suction unit is large, there is a risk that air will be drawn into the head from the nozzle when air bubbles are drawn from the storage unit. If the suction flow rate by the suction unit is small, the pressure loss in the discharge flow path through which the liquid flows will be small, so there is a risk that air bubbles will be drawn from one storage unit while liquid will be drawn from another storage unit. Therefore, it is preferable that the suction flow rate by the suction unit is large enough to prevent air from being drawn into the head from the nozzle.

[0131] The viscosity of the liquid changes depending on the ambient temperature. When the viscosity of the liquid changes, the pressure loss in the discharge flow path through which the liquid flows changes. For example, when the ambient temperature drops, the viscosity of the liquid increases, which increases the pressure loss in the discharge flow path through which the liquid flows. In this case, while it becomes difficult to suck in the liquid, the pressure in the reservoir connected to the discharge flow path through which the air bubbles flow tends to become lower than necessary. Therefore, when the ambient temperature is low, there is a greater risk of air being drawn into the head from the nozzle.

[0132] According to the above configuration, when the ambient temperature is low, the suction flow rate of the suction unit is reduced compared to when the ambient temperature is high, thereby reducing the pressure loss in the discharge flow path through which the liquid flows. This prevents the pressure in the reservoir, to which the discharge flow path through which the bubbles flow, from becoming lower than necessary. This reduces the risk of air being drawn into the head from the nozzle.

[0133] (G) In the liquid ejection device, the reservoir may have an adjustment valve that opens and closes the supply flow path, and the adjustment valve may open the supply flow path when the pressure inside the head falls below a predetermined pressure. According to the above configuration, the pressure inside the head is adjusted by the adjustment valve, allowing the head to eject liquid appropriately. [Explanation of symbols]

[0134] 11...liquid ejection device, 12...head, 13...nozzle, 14...carriage, 15...mounting portion, 16...supply source, 17...supply flow path, 18...first supply flow path, 19...second supply flow path, 20...storage portion, 21...discharge flow path, 22...junction flow path, 23...opening portion, 24...maintenance unit, 25...suction portion, 26...connecting portion, 27...accommodating portion, 28...cap, 29...switching portion, 30...starting portion, 31...detecting portion, 32...control portion, 34...storage chamber, 35...filter chamber, 36...first filter chamber, 37...second filter chamber, 38...storage body, 39...flexible membrane, 40...compartment wall, 41...through hole, 42...separation wall, 43...mounting hole, 44...filter, 45...regulating valve, 46...regulating valve body, 47...regulating spring, 48...shaft portion , 49...plate portion, 50...contact plate, 51...first discharge flow path, 52...second discharge flow path, 53...resistance portion, 54...first container, 55...first on-off valve, 56...second container, 57...second on-off valve, 58...first connection port, 59...first opening plate, 60...first on-off valve body, 61...first on-off spring, 62...first shaft portion, 63...first plate portion, 64...second connection port, 65...second Opening plate, 66...second opening / closing valve body, 67...second opening / closing spring, 68...second shaft portion, 69...second plate portion, 71...confluence portion, 72...confluence fluid, 73...flexible membrane, 74...first operating plate, 75...second operating plate, 76...insertion portion, 77...insertion body, 78...valve portion, 79...seal portion, 80...connection port, 81...first opening member, 82...second opening member, 83...interlocking portion, 99...medium.

Claims

1. a head having nozzles, the head discharging liquids supplied from a plurality of supply sources from the nozzles; a plurality of supply channels connected to the plurality of supply sources and the head; a plurality of reservoirs located in the plurality of supply channels, each reservoir having a reservoir chamber for storing liquid supplied from the plurality of supply sources; a plurality of discharge flow paths connected to the plurality of storage sections, respectively, for discharging bubbles from the plurality of storage chambers; a suction unit that applies negative pressure to the plurality of discharge flow paths; a carriage carrying the head and a plurality of the reservoirs, the carriage scanning the medium; a confluence flow path connected to the plurality of discharge flow paths; a connection portion connectable to the junction flow path, Each of the plurality of discharge flow paths has a resistance portion that causes a larger pressure loss than the corresponding one of the supply flow paths, the connecting portion is connected to the junction channel by the carriage moving to a predetermined position; The liquid ejection device is characterized in that the suction unit applies a negative pressure to the plurality of discharge flow paths via the connection unit.

2. the discharge flow path has a plurality of on-off valves, The storage section is A filter that captures foreign matter; a filter chamber located upstream of the storage chamber, in which the filter is located; The discharge flow path is a first discharge flow path communicating with the storage chamber; a second discharge flow path communicating with the filter chamber; The plurality of on-off valves include a first on-off valve provided in the first discharge flow path; a second on-off valve provided in the second discharge flow path, 2. The liquid ejection device according to claim 1, wherein the first on-off valve and the second on-off valve are opened and closed individually in conjunction with movement of the carriage.

3. the junction flow path has an insertion portion into which the connection portion is inserted, The insertion portion is a seal portion that is fitted tightly to the outer periphery of the connection portion by inserting the connection portion; a valve portion that opens the junction flow path when the connecting portion is inserted into the valve portion, the suction unit is driven in a state where the seal unit is in close contact with the connection unit and the merging flow path is closed by the valve unit, 3. The liquid ejection device according to claim 1, wherein the carriage opens the confluent flow path by moving so that the connection portion is inserted into the insertion portion after the negative pressure in the suction portion reaches a predetermined pressure.

4. a cap that contacts the head so as to cover the nozzle, the cap being connected to the suction unit; 4. The liquid ejection device according to claim 1, further comprising a switching unit that switches the connection destination of the suction unit between the connection unit and the cap.

5. a detection unit that detects an environmental temperature; a control unit that controls the suction unit, The liquid ejection device according to any one of claims 1 to 4, characterized in that the control unit reduces the suction flow rate by the suction unit when the environmental temperature detected by the detection unit is low compared to when the environmental temperature is high.

6. the storage section has an adjustment valve that opens and closes the supply flow path, 6. The liquid ejection device according to claim 1, wherein the adjusting valve opens the supply flow path when the pressure inside the head falls below a predetermined pressure.

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