Liquid discharge apparatus and control method of liquid discharge apparatus

Abstract

The present application provides a kind of liquid ejection device and the control method of liquid ejection device.Liquid ejection device has: first storage part (33), it stores liquid;Second storage part (35) is communicated with first storage part via communication passage (34), and is supplied with liquid from first storage part;Supply flow channel (37) supplies liquid from second storage part to liquid ejection head (23);Recycle flow channel (39) recycles liquid from liquid ejection head into first storage part;Pressurizing portion (47) pressurizes in second storage part;Control unit, supply flow channel, liquid ejection head and recycle flow channel constitute the circulation path (11a) that can supply liquid circulation, and control unit can execute the discharge cycle of the circulation of liquid in circulation path while discharging liquid from nozzle (22) and the non-discharge cycle of the circulation of liquid in circulation path without discharging liquid from nozzle.

Description

Technical Field

[0001] This invention relates to a liquid ejection device such as a printer, and a control method for the liquid ejection device. Background Technology

[0002] As exemplified by Patent Document 1, there exists a recording apparatus, as an example of a liquid ejection device, that performs printing by ejecting ink, as an example of a liquid, from a nozzle formed on a recording head, which is an example of a liquid ejection head. The recording apparatus described in Patent Document 1 includes a circulating outgoing channel for supplying ink from an ink tank, as an example of a second storage unit, to a nozzle, and a circulating return channel for recovering ink from the nozzle to a sub-tank, as an example of a first storage unit. The recording apparatus described in Patent Document 1 includes a valve capable of opening and closing the circulating return channel and an air pump, as an example of a pressurizing unit. By pressurizing the ink tank with the air pump while the valve is open, ink is sent to the circulating outgoing channel. A portion of the ink sent to the circulating outgoing channel is discharged from the nozzle. The remaining ink is recovered into the sub-tank through the circulating return channel. This performs ink circulation from the ink tank to the sub-tank.

[0003] Multiple methods can be considered to implement the liquid circulation process between the first storage section, the liquid nozzle, and the second storage section. In such a case, if the second storage section is pressurized by the pressurizing section with the valve open, there is a possibility that the time required for the pressure in the second storage section to rise to the pressure required for the liquid to flow from the second storage section to the liquid nozzle may become longer.

[0004] Patent Document 1: Japanese Patent Application Publication No. 2005-349843 Summary of the Invention

[0005] A liquid ejection device for solving the above-mentioned problems includes: a liquid ejection head capable of ejecting liquid from a nozzle; a first storage unit for storing the liquid; a second storage unit connected to the first storage unit via a communication channel and supplied with the liquid from the first storage unit; a supply channel for supplying the liquid from the second storage unit to the liquid ejection head; a recovery channel for recovering the liquid from the liquid ejection head back to the first storage unit; a first valve disposed in the communication channel and capable of opening and closing the communication channel; a second valve disposed in the supply channel and capable of opening and closing the supply channel; a pressurization unit for pressurizing the second storage unit; and a control unit, wherein the first storage unit, the supply channel, the liquid ejection head, the recovery channel, the second storage unit, and the communication channel constitute a circulation system capable of circulating the liquid. The control unit is capable of performing a discharge cycle and a non-discharge cycle. The discharge cycle involves closing the communication channel by the first valve and closing the supply channel by the second valve, and opening the supply channel by the second valve after pressurizing the second storage unit to a first pressure using the pressurizing unit. This allows the liquid to circulate within the circulation path while being discharged from the nozzle. The non-discharge cycle involves closing the communication channel by the first valve and closing the supply channel by the second valve, and opening the supply channel by the second valve after pressurizing the second storage unit to a second pressure lower than the first pressure using the pressurizing unit. This allows the liquid to circulate within the circulation path without being discharged from the nozzle.

[0006] A control method for a liquid ejection device that solves the above-mentioned problems includes: a liquid ejection head capable of ejecting liquid from a nozzle; a first storage unit for storing the liquid; a second storage unit connected to the first storage unit via a communication channel and supplied with the liquid from the first storage unit; a supply channel for supplying the liquid from the second storage unit to the liquid ejection head; a recovery channel for recovering the liquid from the liquid ejection head back to the first storage unit; a first valve disposed in the communication channel and capable of opening and closing the communication channel; a second valve disposed in the supply channel and capable of opening and closing the supply channel; and a pressurization unit for pressurizing the second storage unit. The first storage unit, the supply channel, the liquid ejection head, the recovery channel, the second storage unit, and the communication channel constitute a circulation system capable of circulating the liquid. In the control method of the liquid ejection device, when implementing a discharge cycle in which the liquid is discharged from the nozzle and circulated within the circulation path, the communication channel is closed by the first valve and the supply channel is closed by the second valve. After pressurizing the second storage unit to a first pressure greater than the meniscus breaking pressure of the nozzle using the pressurizing unit, the supply channel is opened by the second valve. In the case of a non-discharge cycle in which the liquid is circulated within the circulation path without being discharged from the nozzle, the communication channel is closed by the first valve and the supply channel is closed by the second valve. After pressurizing the second storage unit to a second pressure less than the meniscus breaking pressure using the pressurizing unit, the supply channel is opened by the second valve. Attached Figure Description

[0007] Figure 1 A perspective view of one embodiment of the liquid ejection device.

[0008] Figure 2 This is a schematic diagram of a liquid ejection device.

[0009] Figure 3 This is a cross-sectional view showing a portion of a planar flow channel.

[0010] Figure 4 A three-dimensional diagram showing the supply department and the recycling department.

[0011] Figure 5 A three-dimensional diagram showing the supply department and the recycling department.

[0012] Figure 6 An exploded perspective view showing the supply department and the recycling department.

[0013] Figure 7 An exploded perspective view showing the supply department and the recycling department.

[0014] Figure 8 This is a flowchart illustrating the process of excluding loop routines.

[0015] Figure 9 This is a flowchart illustrating the micro-pressurization discharge routine.

[0016] Figure 10 This is a flowchart illustrating a non-exhaustion cycle routine.

[0017] Figure 11 This is a flowchart illustrating a filling loop routine. Detailed Implementation

[0018] Hereinafter, with reference to the accompanying drawings, one embodiment of the liquid ejection device and the control method of the liquid ejection device will be described. The liquid ejection device is an inkjet printer that performs printing by ejecting ink, an example of a liquid, onto a medium such as paper, cloth, vinyl resin, plastic parts, or metal parts.

[0019] In the accompanying drawings, the liquid ejection device is depicted as a device placed on a horizontal plane, with the Z-axis representing the direction of gravity and the X and Y axes representing the directions along the horizontal plane. The X, Y, and Z axes are orthogonal to each other.

[0020] Liquid ejection device

[0021] like Figure 1 As shown, the liquid ejection device 11 may include: a media receiving unit 13 for receiving the media 12; a stacker 14 for accepting the printed media 12; and an operation unit 15, such as a touch panel, for operating the liquid ejection device 11. The liquid ejection device 11 may also include an image reading unit 16 for reading images of the original document and an automatic feeding unit 17 for feeding the original document to the image reading unit 16.

[0022] like Figure 1 as well as Figure 2 As shown, the liquid dispensing device 11 includes a liquid dispensing head 23, a first storage section 33, a connecting channel 34, a second storage section 35, a supply channel 37, a recovery channel 39, a first valve 36, a second valve 38, a pressurizing section 47, and a control section 19. The first storage section 33, the supply channel 37, the liquid dispensing head 23, the recovery channel 39, the second storage section 35, and the connecting channel 34 constitute a circulation path 11a capable of supplying liquid circulation. The liquid dispensing device 11 may include a temperature detection section 80. The liquid dispensing device 11 may include a third valve 40. The liquid dispensing device 11 may include a planar flow channel 75. The liquid dispensing device 11 may include a supply section 81 and a recovery section 82. The liquid dispensing device 11 may include a maintenance component 91.

[0023] like Figure 2 As shown, the liquid ejection device 11 may include a supply mechanism 25, a drive mechanism 26, and a switching mechanism 48. The supply mechanism 25 supplies liquid stored in the liquid collection section 24 to the liquid ejection head 23. The supply mechanism 25 includes a first storage section 33, a connecting channel 34, a second storage section 35, a supply flow channel 37, a recovery flow channel 39, a first valve 36, a second valve 38, and a pressurization section 47. The drive mechanism 26 drives the supply mechanism 25.

[0024] The liquid ejection device 11 may also have multiple supply mechanisms 25. The multiple supply mechanisms 25 can supply different types of liquids to the liquid ejection head 23 respectively. For example, the liquid ejection device 11 can eject inks of multiple colors supplied by the multiple supply mechanisms 25 to perform color printing. A single drive mechanism 26 can centrally drive the multiple supply mechanisms 25. The liquid ejection device 11 may also have multiple drive mechanisms 26 that individually drive the multiple supply mechanisms 25.

[0025] The supply mechanism 25 may include a mounting section 28 for detachably mounting and dismounting the liquid collection section 24. The liquid collection section 24 may include: a collection chamber 29 for collecting liquid; a discharge section 30 for discharging the liquid collected in the collection chamber 29; and a collection section side valve 31 disposed on the discharge section 30. In this embodiment, the collection chamber 29 is a sealed space not connected to the atmosphere. The liquid collection section 24, installed before the mounting section 28, can collect a larger amount of liquid than the supply mechanism 25 can hold.

[0026] The drive mechanism 26 may include a switching mechanism 48 connected to the pressurization unit 47 and a pressure sensor 49 for detecting pressure. The drive mechanism 26 may include: an atmospheric opening channel 50 connected to the first storage unit 33; a pressurization flow channel 51 connected to the second storage unit 35; and a connecting flow channel 52 connecting the atmospheric opening channel 50 and the pressurization flow channel 51 to the pressurization unit 47.

[0027] The drive mechanism 26 may have a first supply membrane 64. The first supply membrane 64 is a membrane through which gas can easily pass but which is difficult for liquid to pass. The first supply membrane 64 is located in the atmospheric open channel 50. The first supply membrane 64 can reduce the possibility of liquid flowing in the atmospheric open channel 50. The first supply membrane 64 can reduce the possibility of liquid flowing from the first storage section 33 to the drive mechanism 26.

[0028] The drive mechanism 26 may have a second supply membrane 69. The second supply membrane 69 is a membrane through which gas can easily pass but which is difficult for liquid to pass. The second supply membrane 69 is located in the pressurized flow channel 51. The second supply membrane 69 can reduce the possibility of liquid flowing in the pressurized flow channel 51. The second supply membrane 69 can reduce the possibility of liquid flowing from the second storage section 35 to the drive mechanism 26.

[0029] The drive mechanism 26 may include: an air chamber 53 separated from the liquid chamber 41 by a flexible member 42; a spring 54 disposed within the air chamber 53; and an air passage 55 connected to the air chamber 53. The spring 54 reduces pressure fluctuations in the liquid within the recovery passage 39 and the liquid nozzle 23 by pressing the flexible member 42. A portion of the liquid chamber 41 is formed by the flexible member 42, and its volume changes by deforming the flexible member 42.

[0030] The switching mechanism 48 includes a thin tube 72 disposed on the connecting flow channel 52 and a first selection valve 73a to an eleventh selection valve 73k capable of opening and closing the flow channel. The thin tube 72 is so thin that the flow of liquid is greatly restricted relative to the flow of air, and it is a curved tube.

[0031] The first selector valve 73a opens the air passage 55 to the atmosphere. The second selector valve 73b opens the air passage 55 to the pressure sensor 49. The third selector valve 73c opens the air passage 55 and connects the pressurization unit 47 to the air chamber 53.

[0032] The fourth selector valve 73d opens the connecting channel 52 between the pressurizing section 47 and the eighth selector valve 73h to the atmosphere. The fifth selector valve 73e opens the connecting channel 52 to the pressure sensor 49. The sixth selector valve 73f and the seventh selector valve 73g open the connecting channel 52 to the atmosphere. The eighth selector valve 73h opens the connecting channel 52. The ninth selector valve 73i opens the capillary section 72 to the atmosphere. The tenth selector valve 73j opens the atmospheric access channel 50 and connects the first storage section 33 to the connecting channel 52. The eleventh selector valve 73k opens the pressurizing channel 51 and connects the second storage section 35 to the connecting channel 52.

[0033] When the pressure inside the air chamber 53 is changed, the switching mechanism 48 opens the second selector valve 73b to the fourth selector valve 73d and closes the other selector valves. In this state, if the pressurizing unit 47 is driven in the forward direction, the air inside the air chamber 53 is discharged through the air passage 55 and the connecting passage 52, thereby reducing the pressure inside the air chamber 53. In this state, if the pressurizing unit 47 is driven in the reverse direction, air is sent into the air chamber 53 through the connecting passage 52 and the air passage 55, thereby increasing the pressure inside the air chamber 53. At this time, the pressure sensor 49 can detect the pressure in the air passage 55 and the air chamber 53. The control unit 19 can control the drive of the pressurizing unit 47 based on the detection result of the pressure sensor 49.

[0034] With the first storage chamber 33 open to the atmosphere, the switching mechanism 48 opens the sixth selection valve 73f and the tenth selection valve 73j. The first storage chamber 62 is connected to the atmosphere via the atmosphere opening passage 50 and the connecting flow channel 52.

[0035] With the second storage chamber 35 open to the atmosphere, the switching mechanism 48 opens the seventh selection valve 73g and the eleventh selection valve 73k. The second storage chamber 68 is connected to the atmosphere via the pressurized flow channel 51 and the connecting flow channel 52.

[0036] When the second storage compartment 35 is pressurized, the switching mechanism 48 opens the first selection valve 73a, the fifth selection valve 73e, the eighth selection valve 73h, and the eleventh selection valve 73k, and closes the other selection valves. In this state, if the pressurizing unit 47 is driven in the forward direction, air flows into the second storage chamber 68 through the air flow channel 55, the connecting flow channel 52, and the pressurizing flow channel 51, thereby increasing the pressure in the second storage chamber 68. At this time, the pressure sensor 49 can detect the pressure in the connecting flow channel 52, the pressurizing flow channel 51, and the second storage chamber 68. The control unit 19 can control the drive of the pressurizing unit 47 based on the detection result of the pressure sensor 49.

[0037] In this embodiment, the pressurizing mechanism 57 is configured to include a pressurizing section 47, an air chamber 53, and an airflow channel 55 communicating with the pressurizing section 47 and the air chamber 53. The micro-pressurizing section 58 is configured to add a liquid chamber 41 to the pressurizing mechanism 57. The micro-pressurizing section 58 has a liquid chamber 41 and a pressurizing mechanism 57 capable of pressurizing the flexible member 42 from the outside of the liquid chamber 41. The micro-pressurizing section 58 pressurizes the liquid in the recovery flow channel 39.

[0038] Liquid nozzle

[0039] The liquid ejector head 23 is capable of ejecting liquid from the nozzle 22. The nozzle 22 is disposed on the nozzle surface 21. The liquid ejector head 23 can be configured such that the nozzle surface 21 is tilted relative to the horizontal. The liquid ejector head 23 can perform printing by ejecting liquid onto the medium 12 in an tilted position. In this embodiment, the liquid ejector head 23 is arranged in a row that spans the width direction of the medium 12. The liquid ejector head 23 can also be configured in a serial manner to perform printing while moving in the width direction of the medium 12.

[0040] The liquid nozzle 23 may have a first connecting portion 44 and a second connecting portion 45. In an inclined position, the first connecting portion 44 may be positioned higher than the second connecting portion 45.

[0041] Maintenance components

[0042] Maintenance component 91 performs various maintenance procedures on liquid nozzle 23. Maintenance component 91 performs wiping, rinsing, and vacuuming as maintenance. Wiping is performed by displacing maintenance component 91 along nozzle face 21. During wiping, maintenance component 91 wipes away liquid adhering to nozzle face 21. Rinsing is performed by spraying liquid from nozzle 22 onto maintenance component 91 while nozzle face 21 is removed from maintenance component 91. Vacuuming drains liquid retained in maintenance component 91 due to rinsing into a discharge tank (not shown).

[0043] Supply channel and recovery channel

[0044] The supply channel 37 supplies liquid from the second storage section 35 to the liquid nozzle 23. The supply channel 37 can be connected to the second connection section 45 of the liquid nozzle 23. It can be configured such that the upstream end of the supply channel 37 is connected to the second storage section 35, and the downstream end of the supply channel 37 is connected to the second connection section 45.

[0045] The recovery channel 39 recovers liquid from the liquid nozzle 23 into the first storage section 33. The recovery channel 39 can be connected to the first connection section 44 of the liquid nozzle 23. It can be configured such that the upstream end of the recovery channel 39 is connected to the first connection section 44 and the downstream end of the recovery channel 39 is connected to the first storage section 33.

[0046] First Storage Section

[0047] The first storage section 33 stores liquid. An upstream end of a communication channel 34 may be connected to the first storage section 33. Liquid is supplied from the liquid receiving section 24 into the first storage section 33. The first storage section 33 may have an inlet section 60 capable of introducing liquid collected in the liquid receiving section 24 mounted on the mounting section 28. The first storage section 33 may include: a device-side valve 61 disposed on the inlet section 60; a first storage chamber 62 for storing liquid; and a liquid volume sensor 63 for detecting the amount of liquid stored in the first storage chamber 62.

[0048] The device-side valve 61 is mounted on the mounting portion 28 via the liquid collection portion 24, thereby opening together with the collection portion-side valve 31. During the mounting of the liquid collection portion 24 onto the mounting portion 28, the device-side valve 61 and the collection portion-side valve 31 remain open. By configuring the device-side valve 61 to open before the collection portion-side valve 31 when the liquid collection portion 24 is mounted on the mounting portion 28, the possibility of liquid leakage from the liquid collection portion 24 can be reduced.

[0049] The inlet section 60 is provided to penetrate the top 65a of the first storage chamber 62. The lower end of the inlet section 60 is located within the first storage chamber 62 and is positioned below the top 65a. The upper end of the inlet section 60 is located outside the first storage chamber 62 and is positioned above the top 65a. The inlet section 60 is mounted on the mounting section 28 via the liquid receiving section 24 and is connected to the outlet section 30 provided by the liquid receiving section 24.

[0050] The lower end of the inlet 60 is located below the nozzle surface 21. Therefore, the first liquid level 66 of the liquid stored in the first storage section 33 varies below the nozzle surface 21. Specifically, the liquid in the liquid collection section 24 is supplied to the first storage section 33 via the outlet 30 and the inlet 60 due to the head difference. In the liquid collection section 24, air is introduced from the first storage section 33 via the inlet 60 and the outlet 30 in the amount of liquid supplied to the first storage section 33. The first liquid level 66 rises with the amount of liquid supplied. When the first liquid level 66 reaches the lower end of the inlet 60, the inflow of air from the first storage section 33 to the liquid collection section 24 is restricted. Since the collection chamber 29 is sealed, the pressure inside the collection chamber 29 decreases with the amount of liquid supplied when the airflow is restricted. When the negative pressure in the storage chamber 29 is greater than the head pressure of the liquid in the storage chamber 29, the supply of liquid from the liquid storage section 24 to the first storage section 33 is restricted.

[0051] The first liquid level 66 drops as liquid is supplied from the first storage section 33 to the second storage section 35. When the first liquid level 66 drops and air flows into the receiving chamber 29 via the inlet section 60 and the outlet section 30, the negative pressure within the receiving chamber 29 decreases. When the negative pressure within the receiving chamber 29 becomes less than the head pressure of the liquid within the receiving chamber 29, liquid is supplied from the liquid receiving section 24 to the first storage section 33. Therefore, while liquid is contained in the liquid receiving section 24, the first liquid level 66 is maintained at a position near the lower end of the inlet section 60, i.e., a standard position. When the liquid contained in the liquid receiving section 24 disappears, the first liquid level 66 is located below the standard position.

[0052] The liquid level sensor 63 can detect when the first liquid level 66 is at the standard position, when the first liquid level 66 is at a position lower than the standard position, and when the first liquid level 66 is at a full position higher than the standard position. When the first liquid level 66 is at the full position, the first storage section 33 stores the maximum amount of liquid.

[0053] An inlet 33a is formed on the first storage section 33, through which liquid from the recovery channel 39 flows in. The inlet 33a is located below the center of the first storage section 33. The inlet 33a can be a through hole that penetrates the first bottom 65b, which serves as the bottom of the first storage chamber 62. The inlet 33a can be located at the center of the first bottom 65b. The first storage chamber 62 and the recovery channel 39 are connected via the inlet 33a.

[0054] The standard position of the first liquid level 66 is located above the position of the inlet 33a in the first storage chamber 62. Therefore, when the first liquid level 66 is in the standard position, the liquid in the first storage section 33 can be supplied to the liquid nozzle 23 via the recovery channel 39.

[0055] Second Storage Section

[0056] The second storage unit 35 is connected to the first storage unit 33 via a connecting channel 34. The downstream end of the connecting channel 34 can be connected to the second storage unit 35. The second storage unit 35 is supplied with liquid from the first storage unit 33.

[0057] The second storage section 35 can be supplied with liquid from the first storage section 33 via the connecting channel 34 using the head difference. When the pressure in the first storage chamber 62 and the second storage chamber 68 is set to atmospheric pressure, the second liquid level 70 in the second storage section 35 becomes the same height as the first liquid level 66. In other words, the second liquid level 70 is maintained at approximately the same height as the lower end of the inlet section 60, i.e., a standard position, and varies within a range below the nozzle surface 21. The liquid in the liquid nozzle 23 is maintained at a negative pressure due to the head difference between the liquid in the first storage section 33 and the liquid in the second storage section 35. When the liquid in the liquid nozzle 23 is consumed, the liquid stored in the second storage section 35 is supplied to the liquid nozzle 23.

[0058] A supply port 35a for supplying liquid into the supply channel 37 may be formed on the second storage section 35. The supply port 35a may be located below the center of the second storage section 35. The supply port 35a may be a through hole that penetrates the second bottom 68b, which serves as the bottom of the second storage chamber 68. The supply port 35a may be located at the center of the second bottom 68b. The second storage chamber 68 and the supply channel 37 are connected via the supply port 35a. A filter 35b may be provided in the second storage section 35. The filter 35b is located in the second storage chamber 68. The filter 35b covers the supply port 35a.

[0059] First valve

[0060] A first valve 36 is disposed in the communication channel 34. The first valve 36 is capable of opening and closing the communication channel 34. The first valve 36 is a one-way valve. The first valve 36 allows the flow of liquid from the first reservoir 33 to the second reservoir 35. The first valve 36 restricts the flow of liquid from the second reservoir 35 to the first reservoir 33. The first valve 36 closes the communication channel 34 when the pressure in the second reservoir 35 is greater than the pressure in the first reservoir 33.

[0061] Second valve and third valve

[0062] A second valve 38 is disposed in the supply channel 37. The second valve 38 can open and close the supply channel 37. A third valve 40 is disposed in the recovery channel 39. A micro-pressurization unit 58 is disposed in the recovery channel 39 between the third valve 40 and the liquid nozzle 23. A liquid chamber 41 is located in the recovery channel 39 between the third valve 40 and the liquid nozzle 23. The third valve 40 can open and close the recovery channel 39. The opening and closing of the second valve 38 and the third valve 40 are controlled by the control unit 19.

[0063] The second valve 38 and the third valve 40 can be closed when the power to the liquid ejection device 11 is turned off. By closing the supply channel 37 and the recovery channel 39, the possibility of liquid leakage from the liquid ejection head 23 can be reduced even if, for example, vibration or impact is applied to the liquid ejection device 11.

[0064] The second valve 38 and the third valve 40 are opened when printing is performed by the liquid ejection device 11. Thus, during printing, liquid is supplied from the second storage section 35 to the supply channel 37. Liquid is supplied from the first storage section 33 to the recovery channel 39. Liquid is supplied from the supply channel 37 and the recovery channel 39 to the liquid ejection head 23.

[0065] planar flow channel

[0066] The planar flow channel 75 is located below the first storage section 33 and the second storage section 35. The planar flow channel 75 includes a portion of the supply flow channel 37 and a portion of the recovery flow channel 39. In addition, the planar flow channel 75 may include at least one of the air flow channel 55, the second valve 38, and the third valve 40.

[0067] like Figure 3 As shown, the planar flow channel 75 has a first flow channel 76, a second flow channel 77, and a third flow channel 78. The first flow channel 76 and the second flow channel 77 extend orthogonally to the third flow channel 78. The second flow channel 77 is located above the first flow channel 76. The third flow channel 78 connects the downstream end of the first flow channel 76 and the upstream end of the second flow channel 77. The third flow channel 78 extends upward from the downstream end of the first flow channel 76 to the upstream end of the second flow channel 77.

[0068] The planar flow channel 75 has a blocking portion 79. The blocking portion 79 blocks the first corner portion 79a formed by the downstream end of the third flow channel 78 and the upstream end of the second flow channel 77. The blocking portion 79 may also be a triangular cross-section that blocks the first corner portion 79a. The blocking portion 79 is separate from the components constituting the planar flow channel 75. Alternatively, the blocking portion 79 may be integrally formed with the components constituting the planar flow channel 75.

[0069] The liquid flowing in the planar flow channel 75 is as follows: Figure 3 As indicated by the arrows, the liquid flows from the first flow channel 76 through the third flow channel 78 into the second flow channel 77. When the liquid flows from the first flow channel 76 into the third flow channel 78, the direction of liquid flow changes to upward. When the liquid flows from the third flow channel 78 into the second flow channel 77, the liquid flows along the surface of the blocking portion 79. Compared to the case where the first corner 79a is not blocked using the blocking portion 79, it is less likely for liquid flow to stagnate at the upstream end of the second flow channel 77. Therefore, the retention of air bubbles in the liquid at the upstream end of the second flow channel 77 can be suppressed.

[0070] The second corner 79b in the planar flow channel 75, opposite to the first corner 79a where the blocking portion 79 is located, can be chamfered. This allows the blocking portion 79 to be formed at the first corner 79a while suppressing the narrowing of the flow channels in the third flow channel 78 and the second flow channel 77. The blocking portion 79 can also block the third corner 79c formed by the downstream end of the first flow channel 76 and the upstream end of the third flow channel 78. The fourth corner 79d in the planar flow channel 75, opposite to the third corner 79c where the blocking portion 79 is located, can also be chamfered. This allows the blocking portion 79 to be formed at the third corner 79c while suppressing the narrowing of the flow channels in the first flow channel 76 and the third flow channel 78.

[0071] Pressurization section

[0072] like Figure 2 As shown, the pressurizing unit 47 pressurizes the second storage unit 35. Along with the pressurization of the second storage unit 35 by the pressurizing unit 47, the first valve 36 closes the communication channel 34. The pressurizing unit 47 is, for example, a pipe pump, which delivers air by rotating a roller while flattening the pipe. Regarding the pipe (not shown) of the pressurizing unit 47, an air flow channel 55 is connected to one end, and a connecting flow channel 52 is connected to the other end. The pressurizing unit 47, when driven in the forward direction, delivers air drawn in from the air flow channel 55 to the connecting flow channel 52. The pressurizing unit 47, when driven in the reverse direction, delivers air drawn in from the connecting flow channel 52 to the air flow channel 55.

[0073] Temperature detection department

[0074] The temperature detection unit 80 detects the temperature of the environment in which the liquid ejection device 11 is used, i.e., the ambient temperature. The temperature detection unit 80 uses the temperature at the location where it is installed as the ambient temperature. The ambient temperature detected by the temperature detection unit 80 can be in Celsius. The control unit 19 can perform various controls based on the ambient temperature detected by the temperature detection unit 80. The temperature detection unit 80 can also detect the temperature of the printing medium 12. The temperature detection unit 80 can also be located near the liquid ejection head 23.

[0075] Supply Department and Recycling Department

[0076] like Figure 4 As shown, the supply unit 81 and the recovery unit 82 may each have a pipe 83. The supply unit 81 and the recovery unit 82 may each have multiple pipes 83. The multiple pipes 83 in the supply unit 81 are used to supply inks of different colors. The multiple pipes 83 in the recovery unit 82 are used to supply inks of different colors. The supply unit 81 and the recovery unit 82 may each have four pipes 83.

[0077] The multiple pipes 83 of the supply section 81 each form part of a different supply channel 37. Each pipe 83 of the supply section 81 includes an end of the supply channel 37. Similarly, the multiple pipes 83 of the recovery section 82 each form part of a different recovery channel 39. Each pipe 83 of the recovery section 82 includes an end of the recovery channel 39. In both the supply section 81 and the recovery section 82, the end of each pipe 83 is connected to a liquid ejector head 23.

[0078] The supply section 81 and the recovery section 82 may each include a connector section 84, an arm section 86, and a clamping section 87. The connector section 84 is externally molded onto multiple tubes 83 in both the supply section 81 and the recovery section 82. Multiple tube insertion holes 84a are formed on the connector section 84. In this embodiment, four tube insertion holes 84a are formed on the connector section 84. The four tube insertion holes 84a are arranged adjacent to each other in one direction. In the flow direction of the liquid flowing from the tubes 83 to the liquid nozzle 23, the downstream ends of the multiple tubes 83 can be inserted into different tube insertion holes 84a.

[0079] like Figure 5 As shown, a first screw insertion hole 84b is formed on the connector portion 84. In this embodiment, two first screw insertion holes 84b are formed on the connector portion 84. The two first screw insertion holes 84b are located on the connector portion 84 with a gap of four tube insertion holes 84a. Screw members 85 are respectively inserted into the two first screw insertion holes 84b. By connecting the screw members 85 inserted into the first screw insertion holes 84b with the screw insertion holes (not shown) of the liquid nozzle 23, the tube 83 and the connector portion 84 are connected to the liquid nozzle 23.

[0080] The arm portion 86 is integrated with the connector portion 84. The arm portion 86 extends from one end and the other end of the connector portion 84. The supply portion 81 and the recovery portion 82 may each have multiple clamping portions 87. The multiple clamping portions 87 are installed at different locations on the tube 83. Each of the multiple clamping portions 87 has a first clamping portion 88 and a second clamping portion 89. The multiple clamping portions 87 clamp the multiple tubes 83 from both sides through the first clamping portion 88 and the second clamping portion 89.

[0081] like Figure 6 as well as Figure 7 As shown, the supply section 81 and the recovery section 82 may include a protective section 90. The protective section 90 may be a strip-shaped membrane. The protective section 90 may be a polyester film. The protective section 90 is provided to cover a plurality of tubes 83 from one side. Insertion holes 90a are formed at the ends of the protective section 90. A plurality of insertion holes 90a may be provided at equal intervals along the short side of the protective section 90.

[0082] The first clamping part 88 includes a first body 88a. A plurality of first recesses 88b are formed on the side surface of the first body 88a. In the first clamping part 88 that overlaps with the plurality of tubes 83 from above, the plurality of first recesses 88b are located on the lower surface of the first body 88a.

[0083] Multiple first recesses 88b open toward the second clamping portion 89. In this embodiment, four first recesses 88b are formed on the first body 88a. The four first recesses 88b are adjacent to each other. Tubes 83 are respectively embedded in the four first recesses 88b. Thus, the first clamping portions 88 partially overlap with the multiple tubes 83.

[0084] The first clamping part 88 has a plurality of protrusions 88g protruding from the first body 88a toward the second clamping part 89. The plurality of protrusions 88g are respectively inserted into the insertion holes 90a of the protective part 90, thereby fixing the protective part 90 onto the first clamping part 88. The end of the protective part 90 is located between the first clamping part 88 and the plurality of tubes 83.

[0085] The first clamping part 88 has two first protrusions 88c. The first protrusions 88c extend from both ends of the first body 88a toward the second clamping part 89. Engaging holes 88d are formed on the first protrusions 88c. The first protrusions 88c are arranged to clamp four tubes 83 from both sides. Alternatively, the connection portion of the arm 86 to the connector 84 can be used as the base end, and the top end portion 86a of the arm 86 can be located between the tubes 83 and the first protrusions 88c.

[0086] The first clamping part 88 has two second protrusions 88e. The second protrusions 88e extend from both ends of the first body 88a. A second screw insertion hole 88f is formed on the second protrusion 88e. A screw component 85 can be inserted into the second screw insertion hole 88f. When it is necessary to fix the first clamping part 88 to other components, the screw component 85 is inserted into the second screw insertion hole 88f, and the screw component 85 inserted into the second screw insertion hole 88f engages with a screw insertion hole (not shown) of other components.

[0087] The second clamping part 89 includes a second body 89a. A plurality of second recesses 89b are formed on the side of the second body 89a. In the second clamping part 89 that overlaps with the plurality of tubes 83 from below, the plurality of second recesses 89b are located on the upper surface of the second body 89a.

[0088] Multiple second recesses 89b open toward the first clamping portion 88. In this embodiment, four second recesses 89b are formed on the second body 89a. The four second recesses 89b are adjacent to each other. Tubes 83 are respectively embedded in the four second recesses 89b. Thus, the second clamping portions 89 partially overlap with the multiple tubes 83.

[0089] The second clamping part 89 has an engaging end 89d. The engaging end 89d is located at both ends of the second body 89a. The second clamping part 89 is located between the first protrusions 88c located at both ends of the first body 88a. The engaging end 89d is inserted into the engaging hole 88d located in the first protrusion 88c, thereby engaging the engaging end 89d with the first protrusion 88c. The first clamping part 88 and the second clamping part 89 are integrated. The four tubes 83 and the top end 86a of the arm 86 can be clamped from both sides by the integrated first clamping part 88 and the second clamping part 89.

[0090] Control Department

[0091] like Figure 1 As shown, the control unit 19 controls various actions performed by the liquid ejection device 11. The control unit 19 can be configured as a circuit, which includes α: one or more processors that execute various processes according to a computer program; β: one or more dedicated hardware circuits that execute at least a portion of the various processes; or γ: a combination thereof. The hardware circuit is, for example, an integrated circuit for a specific purpose. The processor includes a CPU, RAM, and ROM, etc., which store program code or instructions configured to cause the CPU to perform processes. Memory, or computer-readable medium, includes so-called readable media that can be accessed by a general-purpose or special-purpose computer.

[0092] If the liquid level sensor 63 detects that the first liquid level 66 is located below the standard position, the control unit 19 can determine that the liquid collection unit 24 is empty and instruct the user to replace the liquid collection unit 24.

[0093] Control unit 19 is capable of performing discharge and non-discharge cycles. Control unit 19 is capable of performing filling cycles. Control unit 19 is capable of performing micro-pressurized discharge. Control unit 19 is capable of changing the opening and closing of the recovery flow channel 39 controlled by the third valve 40.

[0094] Next, refer to Figures 8 to 11 The flowchart shown illustrates the control method for the liquid ejection device 11. Here, the sequence of steps in each control method can be arbitrarily changed without departing from the purpose of each control method.

[0095] Exhaust circulation

[0096] Reference Figure 8 The discharge cycle routine will be explained. The discharge cycle can be performed at a time when the liquid collection section 24 is initially installed in the mounting section 28. When the discharge cycle is performed at a time when the liquid collection section 24 is initially installed in the mounting section 28, the discharge cycle can also be performed after the filling cycle has been performed. The discharge cycle can also be performed during standby periods such as printing. The discharge cycle can also be performed periodically. The discharge cycle can also be performed on the remaining supply channels 37 and recovery channels 39 after a portion of the multiple supply channels 37 and a portion of the multiple recovery channels 39 have been processed.

[0097] like Figure 8 As shown, in step S101, control unit 19 opens the third valve 40. In step S102, control unit 19 closes the second valve 38. In step S103, control unit 19 pressurizes the second storage unit 35 to a first pressure P1. Control unit 19 pressurizes the second storage unit 35 to the first pressure P1 by driving pressurizing unit 47. The first pressure P1 is a pressure greater than the meniscus breaking pressure of nozzle 22.

[0098] In step S104, the control unit 19 determines whether a first pressurization time T1 has elapsed since the second storage unit 35 was pressurized in step S103. The first pressurization time T1 is the time required for the second storage unit 35 to be pressurized to a first pressure P1.

[0099] Before the first pressurization time T1 has elapsed, step S104 is NOT. The control unit 19 remains in standby mode until the first pressurization time T1 has elapsed. When the first pressurization time T1 has elapsed, step S104 becomes ON. The control unit 19 proceeds to step S105. In step S105, the control unit 19 opens the second valve 38. In step S106, the control unit 19 pressurizes the second storage unit 35 to the first pressure P1. In step S107, the control unit 19 determines whether a first predetermined time Tp1 has elapsed since the second valve 38 was opened in step S105. The first predetermined time Tp1 is the time required for the second storage unit 35 to be pressurized to the first pressure P1 while the second valve 38 is open.

[0100] The first pressurization time T1 and the first predetermined time Tp1 can be preset or changed each time a discharge cycle is performed. It can be configured such that the control unit 19 sets the first pressurization time T1 and the first predetermined time Tp1 to be longer when the ambient temperature is a first temperature compared to when the ambient temperature is a second temperature higher than the first temperature. Alternatively, it can be configured such that the control unit 19 sets the first pressurization time T1 and the first predetermined time Tp1 to be longer as the ambient temperature decreases. The control unit 19 can also use different first pressurization times T1 and first predetermined times Tp1 in each of a plurality of preset temperature ranges. In such cases, even if the ambient temperatures are different, if they are within the same temperature range, the same value is used as the first pressurization time T1. Similarly, even if the ambient temperatures are different, if they are within the same temperature range, the same value is used as the first predetermined time Tp1. If the ambient temperatures are different and within different temperature ranges, different values ​​are used as the first pressurization time T1. If the ambient temperatures are different and fall within different temperature ranges, then different values ​​are used as the first predetermined time Tp1.

[0101] Furthermore, the aforementioned first pressurization time T1 is set such that, from the time the second storage unit 35 is pressurized until the first pressurization time T1 has elapsed, the amount of liquid supplied from the second storage unit 35 to the supply channel 37 is within a specified range. The aforementioned first predetermined time Tp1 is set such that, from the time the second storage unit 35 is pressurized until the first predetermined time Tp1 has elapsed, the amount of liquid supplied from the second storage unit 35 to the supply channel 37 is within a specified range. The specified range of liquid volume refers to a range where the amount of liquid required for the discharge cycle can be supplied to the supply channel 37, and the amount of liquid stored in the second storage unit 35 is not less than a specified amount.

[0102] Before the first predetermined time Tp1 has elapsed, step S107 is "No". Control unit 19 remains in standby mode until the first predetermined time Tp1 has elapsed. When the first predetermined time Tp1 has elapsed, step S107 becomes "Yes". Control unit 19 proceeds to step S108. In step S108, control unit 19 stops pressurizing the second storage unit 35. In step S109, control unit 19 opens the second storage unit 35 to the atmosphere. In step S110, control unit 19 closes the second valve 38. In step S111, control unit 19 closes the third valve 40. In step S112, control unit 19 determines whether a liquid level recovery time has elapsed since the second valve 38 was closed in step S110. The liquid level recovery time is the time required for the second liquid level 70 in the second storage unit 35 to reach the standard position.

[0103] Before the liquid level recovery time has elapsed, step S112 is "No". The control unit 19 remains in standby mode until the liquid level recovery time has elapsed. When the liquid level recovery time has elapsed, step S112 becomes "Yes". The control unit 19 then proceeds to step S113. In step S113, the control unit 19 determines whether the processing steps S101 to S112 have been executed for the nth time in this discharge cycle routine.

[0104] In this discharge cycle routine, when the liquid collection unit 24 is initially installed on the mounting unit 28, the control unit 19 performs a determination using the first predetermined number n1 as the nth time in step S113. When the ambient temperature is below the predetermined temperature, the first predetermined number n1 can be less than when the ambient temperature is above the predetermined temperature. The first predetermined number n1 can be two times when the ambient temperature is below the predetermined temperature. The first predetermined number n1 can be three times when the ambient temperature is above the predetermined temperature.

[0105] In the case where the current discharge cycle is executed during standby when printing or other processes are not in progress, in step S113, the control unit 19 uses the second predetermined number n2 as the nth time for judgment. The second predetermined number n2 can be less than the first predetermined number n1. If the first predetermined number n1 is two or three times, the second predetermined number n2 can be one time.

[0106] Before the processing of steps S101 to S112 is executed for the nth time in this discharge cycle routine, step S113 is NOT. Control unit 19 executes the processing of steps S101 to S113 again. In this discharge cycle routine, when the processing of steps S101 to S113 is executed for the nth time, step S113 becomes Yes. Control unit 19 causes the processing to proceed to step S114. In step S114, control unit 19 performs wiping by maintenance member 91. In step S115, control unit 19 executes the micro-pressure discharge routine, and then ends the discharge cycle routine. In addition, at least two of steps S108, S109, S110, and S111 can be executed simultaneously.

[0107] like Figure 2 As shown, during the discharge cycle, with the recovery channel 39 open, the control unit 19 pressurizes the second storage unit 35 and opens the second valve 38. Therefore, liquid flows from the second storage unit 35 into the supply channel 37. The liquid is supplied to the liquid nozzle 23 through the supply channel 37. A portion of the liquid supplied to the liquid nozzle 23 is discharged from the nozzle 22. Liquid is recovered from the liquid nozzle 23 into the recovery channel 39. The liquid returns to the first storage unit 33 through the recovery channel 39.

[0108] During the discharge cycle, air bubbles trapped in the liquid nozzle 23, supply channel 37, and recovery channel 39 flow together with the liquid into the first storage section 33. This reduces the number of air bubbles trapped in the liquid nozzle 23, supply channel 37, and recovery channel 39.

[0109] Micro-pressure discharge

[0110] Reference Figure 9 The procedure for micro-pressure discharge is explained. Micro-pressure discharge can also be performed when micro-pressure discharge is specified.

[0111] like Figure 9 As shown, in step S201, control unit 19 opens the second valve 38. In step S202, control unit 19 opens the third valve 40. In step S203, control unit 19 depressurizes the air chamber 53. In step S204, control unit 19 determines whether a depressurization time has elapsed since the air chamber 53 was depressurized. The depressurization time is the time required for the flexible member 42 to deform and for the volume of the liquid chamber 41 to reach its maximum.

[0112] Before the decompression time has elapsed, step S204 is "No". Control unit 19 remains in standby mode until the decompression time has elapsed. When the decompression time has elapsed, step S204 becomes "Yes". Control unit 19 proceeds to step S205. In step S205, control unit 19 closes the second valve 38. In step S206, control unit 19 closes the third valve 40. In step S207, control unit 19 opens the air chamber 53 to atmospheric pressure. In step S208, control unit 19 performs wiping by maintenance component 91. In step S209, control unit 19 performs flushing by maintenance component 91. In step S210, control unit 19 performs air suction by maintenance component 91, and then ends the micro-pressurization discharge routine.

[0113] Here, steps S201 and S202 can be performed simultaneously with step S203, or after step S203. Furthermore, steps S205 and S206 can be performed during the implementation of step S203, at the same time as the end of step S203, or after the end of step S203.

[0114] like Figure 2As shown, during micro-pressurized discharge, the control unit 19 opens the supply channel 37 and the recovery channel 39 by opening the second valve 38 and the third valve 40. The control unit 19 increases the volume of the liquid chamber 41 by depressurizing the air chamber 53, thereby deforming the flexible member 42. Liquid flows into the liquid chamber 41 from the first storage unit 33 via the recovery channel 39, and liquid also flows into the liquid chamber 41 from the second storage unit 35 via the supply channel 37 and the recovery channel 39.

[0115] When the volume of the liquid chamber 41 reaches its maximum, the control unit 19 closes the supply channel 37 by closing the second valve 38. The control unit 19 also closes the recovery channel 39 by closing the third valve 40. Since the deformation of the flexible component 42, achieved through the decompression of the air chamber 53, is relieved, the volume of the liquid chamber 41 decreases. As a result, the liquid ejection device 11 discharges liquid from the nozzle 22 via the pressurization mechanism 57. The pressurization mechanism 57 pressurizes the liquid chamber 41 with pressure that disrupts the meniscus formed in the nozzle 22. The amount of liquid discharged from the liquid ejection head 23 through micro-pressurization is less than the amount of liquid discharged from the liquid ejection head 23 through discharge circulation.

[0116] Non-exhaustion circulation

[0117] Reference Figure 10 The non-exhaust cycle routine will be explained. The non-exhaust cycle can be executed after the fill cycle and the exhaust cycle have been executed, and in standby mode when printing or other processes are not being performed. The non-exhaust cycle can also be executed periodically.

[0118] like Figure 10 As shown, in step S301, control unit 19 opens the third valve 40. In step S302, control unit 19 closes the second valve 38. In step S303, control unit 19 pressurizes the second storage unit 35 to a second pressure P2. Control unit 19 pressurizes the second storage unit 35 to the second pressure P2 by driving pressurizing unit 47. The second pressure P2 is less than the meniscus breaking pressure of nozzle 22. The second pressure P2 is less than the first pressure P1 used in the discharge cycle.

[0119] In step S304, the control unit 19 determines whether a second pressurization time T2 has elapsed since the second storage unit 35 was pressurized in step S303. The second pressurization time T2 is the time required for the second storage unit 35 to be pressurized to the second pressure P2.

[0120] Before the second pressurization time T2 has elapsed, step S304 is "No". Control unit 19 remains in standby mode until the second pressurization time T2 has elapsed. When the second pressurization time T2 has elapsed, step S304 becomes "Yes". Control unit 19 proceeds to step S305. In step S305, control unit 19 opens the second valve 38. In step S306, control unit 19 pressurizes the second storage unit 35 to the second pressure P2. In step S307, control unit 19 determines whether a second predetermined time Tp2 has elapsed since the second valve 38 was opened in step S305. The second predetermined time Tp2 is the time required for the second storage unit 35 to be pressurized to the second pressure P2 while the second valve 38 is open.

[0121] The second pressurization time T2 and the second predetermined time Tp2 can be preset or changed each time a non-discharge cycle is performed. The second pressurization time T2 can be shorter than the first pressurization time T1 used in the discharge cycle. The second predetermined time Tp2 can be longer than the first predetermined time Tp1 used in the discharge cycle.

[0122] When the ambient temperature is a first temperature, the control unit 19 can set the second pressurization time T2 and the second predetermined time Tp2 to be longer compared to when the ambient temperature is a second temperature higher than the first temperature. Alternatively, the control unit 19 can set the second pressurization time T2 and the second predetermined time Tp2 to be longer as the ambient temperature decreases. The control unit 19 can also use the number of seconds obtained by multiplying the ambient temperature by 0.5 and then adding 37.5 as the second pressurization time T2 and the second predetermined time Tp2. The control unit 19 can also use different second pressurization times T2 and second predetermined times Tp2 for each of a plurality of preset temperature ranges. In such cases, even if the ambient temperatures are different, if they are within the same temperature range, the same value is used for the second pressurization time T2. Similarly, even if the ambient temperatures are different, if they are within the same temperature range, the same value is used for the second predetermined time Tp2. If the ambient temperatures are different and within different temperature ranges, different values ​​are used for the second pressurization time T2. If the ambient temperatures are different and fall within different temperature ranges, then different values ​​are used as the second predetermined time Tp2.

[0123] Furthermore, the aforementioned second pressurization time T2 is set such that, from the time the second storage unit 35 is pressurized until the second pressurization time T2 has elapsed, the amount of liquid supplied from the second storage unit 35 to the supply channel 37 is within a specified range. The aforementioned second predetermined time Tp2 is set such that, from the time the second storage unit 35 is pressurized until the second predetermined time Tp2 has elapsed, the amount of liquid supplied from the second storage unit 35 to the supply channel 37 is within a specified range. The specified range of liquid volume refers to a range where the amount of liquid not required for the discharge cycle can be supplied to the supply channel 37, and the amount of liquid stored in the second storage unit 35 is not less than a specified amount.

[0124] Before the second predetermined time Tp2 has elapsed, step S307 is "No". Control unit 19 remains in standby mode until the second predetermined time Tp2 has elapsed. When the second predetermined time Tp2 has elapsed, step S307 becomes "Yes". Control unit 19 proceeds to step S308. In step S308, control unit 19 stops pressurizing the second storage unit 35. In step S309, control unit 19 opens the second storage unit 35 to atmospheric pressure. In step S310, control unit 19 closes the second valve 38. In step S311, control unit 19 closes the third valve 40. In step S312, control unit 19 performs wiping by maintenance component 91. In step S313, control unit 19 executes a micro-pressurization discharge routine, and then ends the non-discharge cycle routine. Furthermore, at least two of steps S308, S309, S310, and S311 can be performed simultaneously.

[0125] like Figure 2 As shown, in the non-discharge cycle, with the recovery channel 39 open, the control unit 19 pressurizes the second storage unit 35 and opens the second valve 38. Therefore, liquid flows from the second storage unit 35 into the supply channel 37. The liquid is supplied to the liquid nozzle 23 through the supply channel 37. Liquid ejection from the nozzle 22 can be suppressed. Liquid is recovered from the liquid nozzle 23 into the recovery channel 39. The liquid returns to the first storage unit 33 through the recovery channel 39.

[0126] In the non-discharge cycle, liquid flows from the second storage section 35 into the supply channel 37, thereby agitating the liquid stored in the second storage section 35. In the non-discharge cycle, liquid flows from the recovery channel 39 into the first storage section 33, thereby agitating the liquid stored in the first storage section 33.

[0127] Filling loop

[0128] Reference Figure 11The filling cycle routine will be described. The filling cycle can be performed after the liquid receiving section 24 is initially installed in the mounting section 28 and the first liquid level 66 in the first storage section 33 and the second liquid level 70 in the second storage section 35 are in the standard position.

[0129] like Figure 11 As shown, in step S401, control unit 19 opens the third valve 40. In step S402, control unit 19 closes the second valve 38. In step S403, control unit 19 pressurizes the second storage unit 35 to a third pressure P3. Control unit 19 pressurizes the second storage unit 35 to the third pressure P3 by driving pressurizing unit 47. The third pressure P3 is a pressure less than the first pressure P1 used in the discharge cycle and greater than the second pressure P2 used in the non-discharge cycle.

[0130] In step S404, the control unit 19 determines whether a third pressurization time T3 has elapsed since the second storage unit 35 was pressurized in step S403. The third pressurization time T3 is the time required for the second storage unit 35 to be pressurized to the third pressure P3.

[0131] Before the third pressurization time T3 has elapsed, step S404 is "No". Control unit 19 remains in standby mode until the third pressurization time T3 has elapsed. When the third pressurization time T3 has elapsed, step S404 becomes "Yes". Control unit 19 proceeds to step S405. In step S405, control unit 19 opens the second valve 38. In step S406, control unit 19 pressurizes the second storage unit 35 to the third pressure P3. In step S407, control unit 19 determines whether a third predetermined time Tp3, which is a predetermined time, has elapsed since the second valve 38 was opened in step S405. The third predetermined time Tp3 is the time required for the second storage unit 35 to be pressurized to the third pressure P3 while the second valve 38 is open.

[0132] The third pressurization time T3 and the third predetermined time Tp3 can be preset or variable. The third pressurization time T3 can be shorter than the first pressurization time T1 used in the discharge cycle. The third pressurization time T3 can be the same as or a different time than the second pressurization time T2 used in the non-discharge cycle. The third predetermined time Tp3 can be longer than the first predetermined time Tp1 used in the discharge cycle. The third predetermined time Tp3 can be the same as or a different time than the second predetermined time Tp2 used in the non-discharge cycle.

[0133] When the ambient temperature is a first temperature, the control unit 19 can set the third pressurization time T3 and the third predetermined time Tp3 to be longer compared to when the ambient temperature is a second temperature higher than the first temperature. Alternatively, the control unit 19 can set the third pressurization time T3 and the third predetermined time Tp3 to be longer as the ambient temperature decreases. The control unit 19 can also use different third pressurization times T3 and third predetermined times Tp3 for each of a plurality of preset temperature ranges. In such cases, even if the ambient temperatures are different, if they are within the same temperature range, the same value is used for the third pressurization time T3. Even if the ambient temperatures are different, if they are within the same temperature range, the same value is used for the third predetermined time Tp3. If the ambient temperatures are different and within different temperature ranges, different values ​​are used for the third pressurization time T3. If the ambient temperatures are different and within different temperature ranges, different values ​​are used for the third predetermined time Tp3.

[0134] Furthermore, the aforementioned third pressurization time T3 is set such that, from the time the second storage unit 35 is pressurized until the third pressurization time T3 has elapsed, the amount of liquid supplied from the second storage unit 35 to the supply channel 37 is within a specified range. The aforementioned third predetermined time Tp3 is set such that, from the time the second storage unit 35 is pressurized until the third predetermined time Tp3 has elapsed, the amount of liquid supplied from the second storage unit 35 to the supply channel 37 is within a specified range. The specified range of liquid volume refers to a range where the amount of liquid required for filling the cycle can be supplied to the supply channel 37, and the amount of liquid stored in the second storage unit 35 is not less than a specified amount.

[0135] Before the third predetermined time Tp3 has elapsed, step S407 is "No". Control unit 19 remains in standby mode until the third predetermined time Tp3 has elapsed. When the third predetermined time Tp3 has elapsed, step S407 becomes "Yes". Control unit 19 proceeds to step S408. In step S408, control unit 19 stops pressurizing the second storage unit 35. In step S409, control unit 19 opens the second storage unit 35 to the atmosphere. In step S410, control unit 19 closes the second valve 38. In step S411, control unit 19 closes the third valve 40. In step S412, control unit 19 determines whether a liquid level recovery time has elapsed since the second valve 38 was closed in step S410. The liquid level recovery time is the time required for the second liquid level 70 in the second storage unit 35 to return to the standard position.

[0136] Before the liquid level recovery time has elapsed, step S412 is "No". Control unit 19 remains in standby mode until the liquid level recovery time has elapsed. When the liquid level recovery time has elapsed, step S412 becomes "Yes". Control unit 19 proceeds to step S413. In step S413, control unit 19 determines whether the processing of steps S401 to S412 has been executed for the Nth time in this filling cycle routine. Control unit 19 uses a preset third predetermined number n3 as the Nth time for this determination. The third predetermined number n3 can be two.

[0137] Before the number of times steps S401 to S412 are executed in this cycle routine becomes N, step S413 is NOT. Control unit 19 executes steps S401 to S413 again. When the number of times steps S401 to S413 are executed in this filling cycle routine becomes N, step S413 becomes Yes. Control unit 19 causes the process to proceed to step S414. In step S414, control unit 19 performs wiping by maintenance member 91. In step S415, control unit 19 executes the micro-pressure discharge routine, and then ends the filling cycle routine. In addition, at least two of steps S408, S409, S410, and S411 can be executed simultaneously.

[0138] like Figure 2 As shown, during the filling cycle, with the recovery channel 39 open, the control unit 19 pressurizes the second storage unit 35 and opens the second valve 38. Therefore, liquid flows from the second storage unit 35 into the supply channel 37. The liquid is supplied to the liquid nozzle 23 through the supply channel 37. A portion of the liquid supplied to the liquid nozzle 23 is discharged from the nozzle 22. Liquid is recovered from the liquid nozzle 23 into the recovery channel 39. The liquid returns to the first storage unit 33 through the recovery channel 39.

[0139] During the filling cycle, liquid flows into the supply channel 37, the liquid nozzle 23, and the recovery channel 39. Thus, while liquid is discharged from the nozzle 22, liquid is filled into the circulation path 11a.

[0140] The role of the implementation method

[0141] The function of this embodiment will be explained.

[0142] During the discharge cycle, the control unit 19 closes the communication channel 34 via the first valve 36 and the supply channel 37 via the second valve 38. The control unit 19 pressurizes the second storage section 35 to a first pressure P1 via the pressurizing unit 47. After closing the communication channel 34 and the supply channel 37, and after pressurizing the second storage section 35 to the first pressure P1, the control unit 19 opens the supply channel 37 via the second valve 38. Thus, the control unit 19 can perform a discharge cycle that circulates liquid within the circulation path 11a while discharging liquid from the nozzle 22.

[0143] In the non-discharge cycle, the control unit 19 closes the communication channel 34 via the first valve 36 and the supply channel 37 via the second valve 38. The control unit 19 pressurizes the second storage section 35 to a second pressure P2, which is lower than the first pressure P1, via the pressurization unit 47. After closing the communication channel 34 and the supply channel 37, and after pressurizing the second storage section 35 to the second pressure P2, the control unit 19 opens the supply channel 37 via the second valve 38. Thus, the control unit 19 can execute a non-discharge cycle in which liquid circulates within the circulation path 11a without discharging liquid from the nozzle 22.

[0144] During the filling cycle, the control unit 19 closes the communication channel 34 via the first valve 36 and the supply channel 37 via the second valve 38. The control unit 19 pressurizes the second storage section 35 to a pressure less than the first pressure P1 and greater than the second pressure P2, i.e., a third pressure P3, via the pressurizing unit 47. The control unit 19 closes the communication channel 34 and the supply channel 37, and after pressurizing the second storage section 35 to the third pressure P3, it opens the supply channel 37 via the second valve 38. Thus, the control unit 19 can perform a filling cycle in which liquid is filled within the circulation path 11a while liquid is being discharged from the nozzle 22.

[0145] During the discharge cycle, non-discharge cycle, and filling cycle, as the second storage section 35 is pressurized by the pressurization section 47, the pressure in the second storage section 35 becomes greater than the pressure in the first storage section 33. As a result, the first valve 36 closes the communication channel 34.

[0146] In the discharge cycle, non-discharge cycle, and filling cycle, the control unit 19 closes the supply channel 37 via the second valve 38. The control unit 19 closes both the connecting channel 34 and the supply channel 37, and after pressurizing the second storage section 35, opens the supply channel 37 via the second valve 38. The control unit 19 pressurizes the second storage section 35 while the second valve 38 is closed. Therefore, compared to pressurizing the second storage section 35 while the second valve 38 is open, the second storage section 35 can be pressurized more quickly.

[0147] In the discharge cycle, non-discharge cycle, and filling cycle, after the control unit 19 opens the supply channel 37 via the second valve 38, it pressurizes the second storage compartment 35 via the pressurization unit 47. This reduces the pressure drop in the second storage compartment 35 caused by the opening of the supply channel 37 via the second valve 38. In other words, after opening the supply channel 37 via the second valve 38, the control unit 19 pressurizes the second storage compartment 35 via the pressurization unit 47 to minimize the pressure drop in the second storage compartment 35 caused by the opening of the supply channel 37 via the second valve 38.

[0148] During the discharge cycle, non-discharge cycle, and filling cycle, the control unit 19, with the recovery channel 39 open, pressurizes the second storage section 35 and opens the second valve 38. Therefore, the liquid flowing in the recovery channel 39 flows into the first storage section 33 via the inlet 33a. The liquid stored in the first storage section 33 is agitated by the inflow of liquid from the inlet 33a.

[0149] In the discharge cycle, non-discharge cycle, and filling cycle, the control unit 19 closes the supply channel 37 after a predetermined time has elapsed since the supply channel 37 has been opened via the second valve 38. The lower the ambient temperature, the higher the viscosity of the liquid. Therefore, there is a possibility that the flow rate of the liquid flowing in the supply channel 37, which accompanies the opening of the supply channel 37 via the second valve 38, may vary depending on the ambient temperature. When the ambient temperature detected by the temperature detection unit 80 is a first temperature, the control unit 19 sets the predetermined time to be longer than when the ambient temperature is a second temperature higher than the first temperature. Therefore, it is possible to suppress the situation where the flow rate of the liquid flowing in the circulation path 11a increases or decreases with changes in ambient temperature.

[0150] Effects of the implementation method

[0151] The effects of this implementation method will be explained.

[0152] (1) The control unit 19 is capable of performing discharge cycles and non-discharge cycles. Multiple processes, such as discharge cycles and non-discharge cycles, can be implemented using a shared circulation path 11a. Therefore, compared to implementing multiple processes using different paths, the complexity of the liquid flow path can be suppressed. Furthermore, in both discharge and non-discharge cycles, the communication channel 34 (operated by the first valve 36) and the supply channel 37 (operated by the second valve 38) are closed before the supply channel 37 (operated by the second valve 38) is opened, and pressurization is performed in the second storage section 35 by the pressurization unit 47. Therefore, compared to the case where pressurization in the second storage section 35 is performed after the supply channel 37 (operated by the second valve 38) is opened, the liquid can circulate in the circulation path 11a earlier in both discharge and non-discharge cycles. Therefore, the time required for multiple processes, such as discharge cycles and non-discharge cycles, can be shortened.

[0153] (2) The control unit 19 is capable of performing a filling cycle. It can implement a shared circulation path 11a for the discharge cycle, the non-discharge cycle, and the filling cycle, which are treated differently from them. Therefore, it is possible to further suppress the complexity of the liquid flow path. Furthermore, in the filling cycle, the communication channel 34 (operated by the first valve 36) and the supply channel 37 (operated by the second valve 38) are closed before the supply channel 37 is opened by the second valve 38, and pressurization is performed in the second storage section 35 by the pressurization unit 47. Therefore, compared to the case where pressurization in the second storage section 35 is performed after the supply channel 37 is opened by the second valve 38, the liquid can be circulated in the circulation path 11a earlier in the filling cycle. Therefore, the time required for the filling cycle can be shortened.

[0154] (3) After the control unit 19 opens the supply channel 37 via the second valve 38, it pressurizes the second storage compartment 35 via the pressurizing unit 47 to reduce the pressure drop in the second storage compartment 35 caused by the opening of the supply channel 37 via the second valve 38. Therefore, compared to the case where the pressurizing of the second storage compartment 35 is not performed by the pressurizing unit 47 after the opening of the supply channel 37 via the second valve 38, the pressure drop in the second storage compartment 35 caused by the opening of the supply channel 37 via the second valve 38 can be reduced. Therefore, the pressure in the second storage compartment 35 required for the circulation of liquid in the circulation path 11a and the discharge of liquid from the nozzle 22 can be maintained.

[0155] (4) The first valve 36 is a one-way valve, and the communication channel 34 is closed when the second storage section 35 is pressurized by the pressurizing section 47. Therefore, a drive mechanism for driving the first valve 36 is no longer needed. Therefore, it is possible to suppress the increase in the number of components mounted on the liquid ejection device 11.

[0156] (5) The lower the ambient temperature, the higher the viscosity of the liquid. Therefore, there is a possibility that the flow rate of the liquid flowing in the supply channel 37, which is opened by the second valve 38, may vary depending on the ambient temperature. After a predetermined time has elapsed since the supply channel 37 has been opened by the second valve 38, the control unit 19 closes the supply channel 37. When the ambient temperature detected by the temperature detection unit 80 is a first temperature, the control unit 19 sets the predetermined time to be longer than when the ambient temperature is a second temperature higher than the first temperature. Therefore, it is possible to suppress the situation where the flow rate of the liquid flowing in the circulation path 11a increases or decreases with changes in ambient temperature.

[0157] (6) An inlet 33a is formed on the first storage section 33, which allows liquid from the recovery channel 39 to flow in. The inlet 33a is located below the center of the first storage section 33. Therefore, liquid flowing in the recovery channel 39 flows into the first storage section 33 via the inlet 33a. Since the inlet 33a is located below the center of the first storage section 33, the liquid stored in the first storage section 33 is agitated by the liquid flowing in from the inlet 33a. Therefore, sedimentation in the first storage section 33 can be restored.

[0158] (7) The control unit 19 can change the opening and closing of the recovery channel 39 controlled by the third valve 40. Therefore, it is possible to switch whether the liquid can flow from the recovery channel 39 to the first storage unit 33.

[0159] Change Example

[0160] This embodiment can be implemented by modifications as follows. This embodiment and the following modifications can be combined with each other to implement them within the scope of technical inconsistency.

[0161] The location of the supply port 35a in the second storage section 35 is not limited to the second bottom 68b. For example, the supply port 35a may also be formed on the side wall connecting the top of the second storage section 35 and the second bottom 68b. The location of the supply port 35a in the second storage section 35 is not limited to a position lower than the center of the second storage section 35. For example, the supply port 35a may also be formed at the top of the second storage section 35.

[0162] The location of the inlet 33a in the first storage section 33 is not limited to the first bottom 65b. For example, the inlet 33a may also be formed on the side wall connecting the top 65a and the first bottom 65b of the first storage section 33. The location of the inlet 33a in the first storage section 33 is not limited to a position lower than the center of the first storage section 33. For example, the inlet 33a may also be formed at the top 65a.

[0163] Micro-pressurized discharge can also be achieved by pressurizing the liquid in the liquid chamber 41 using the spring 54 to press the flexible member 42. In this case, when the control unit 19 increases the volume of the liquid chamber 41 by depressurizing the air chamber 53, the air chamber 53 is opened to atmospheric pressure. When the air chamber 53 becomes atmospheric pressure, the spring 54 presses the liquid in the liquid chamber 41, causing the liquid to be discharged from the liquid nozzle 23.

[0164] • The wiping process can be omitted in at least a portion of the discharge cycle, non-discharge cycle, and filling cycle of the control unit 19. The micro-pressure discharge process can also be omitted in at least a portion of the discharge cycle, non-discharge cycle, and filling cycle of the control unit 19.

[0165] • Control unit 19 may also omit at least one of steps S112 and S113 in the discharge cycle.

[0166] • Control unit 19 may also omit at least one of steps S412 and S413 in the filling cycle.

[0167] • The control unit 19 may also use a preset value for at least one of the first pressurization time T1 in the discharge cycle, the second pressurization time T2 in the non-discharge cycle, and the third pressurization time T3 in the filling cycle.

[0168] • The control unit 19 may also use a preset value for at least one of the first predetermined time Tp1 in the discharge cycle, the second predetermined time Tp2 in the non-discharge cycle, and the third predetermined time Tp3 in the filling cycle. The temperature detection unit 80 may also be omitted from the liquid ejection device 11.

[0169] • The third valve 40 can also be omitted from the liquid ejection device 11. In the discharge cycle, non-discharge cycle, and filling cycle, the control unit 19 can also omit the processing related to the third valve 40. The recovery channel 39 can also remain open at all times.

[0170] • Control unit 19 may omit steps S106 and S107 in the discharge cycle. Control unit 19 may also omit steps S306 and S307 in the non-discharge cycle. Control unit 19 may also omit steps S406 and S407 in the filling cycle.

[0171] • Control unit 19 can also be in Figure 11 Based on the routine of the filling cycle shown, a filling cycle is also implemented that uses a different path than the cycle path 11a to fill the liquid into the supply channel 37.

[0172] • The first valve 36 may also be a control valve that can be controlled to open and close by the control unit 19. The control unit 19 may also close the communication channel 34 by closing the first valve 36 before pressurizing the second storage unit 35.

[0173] The liquid nozzle 23 may also have multiple pressure chambers individually connected to multiple nozzles 22, a common liquid chamber connected to the multiple pressure chambers, and a filter chamber housing a filter. A first connection 44 and a second connection 45 are connected to at least one of the pressure chamber, the common liquid chamber, and the filter chamber. For example, when the first connection 44 and the second connection 45 are connected to the filter chamber, the liquid dispensing device 11 can recover the air bubbles captured by the filter along with the liquid into the first storage section 33 by implementing a discharge cycle.

[0174] The control unit 19 can also depressurize the first storage unit 33 when the liquid flows from the recovery channel 39 into the first storage unit 33. For example, the atmospheric opening channel 50 can also be connected to the air channel 55. Alternatively, the second storage unit 35 can be pressurized by driving the pressurization unit 47 to rotate forward, and the first storage unit 33 can be depressurized via the air channel 55 and the atmospheric opening channel 50.

[0175] • The first storage section 33 and the second storage section 35 can also be constructed as a single unit.

[0176] • The flexible component 42 may also be formed of a rubber membrane, an elastomer membrane, a thin film, etc.

[0177] • The liquid chamber 41 can also be provided in the supply channel 37. The pressurizing mechanism 57 can also pressurize the liquid chamber 41 provided in the supply channel 37.

[0178] • The pressurization section 47 can also use a diaphragm pump, piston pump, or gear pump, etc.

[0179] The inlet section 60 and the outlet section 30 may also have multiple flow channels. For example, one flow channel may allow liquid to flow from the liquid receiving section 24 into the first storage section 33, and another flow channel may allow air to flow from the first storage section 33 into the liquid receiving section 24.

[0180] • The liquid ejector head 23 can also eject liquid in a horizontal position with the nozzle face 21 horizontal to perform printing on the medium 12. The liquid ejector head 23 can also be configured to change the position to a horizontal position or an inclined position.

[0181] • The liquid ejection device 11 may also have an atmospheric opening channel that allows the second storage section 35 to be atmospherically opened, separate from the pressurized flow channel 51.

[0182] The liquid ejection device 11 can also be a liquid ejection device that sprays or ejects liquids other than ink. The state of the liquid ejected from the liquid ejection device as tiny droplets includes granular, teardrop-shaped, and linear tailing states. The liquid referred to here is any material capable of being ejected by the liquid ejection device. For example, the liquid can be any material in a liquid phase state, including liquids with high or low viscosity, sols, gel water, other inorganic solvents, organic solvents, solutions, liquid resins, liquid metals, and molten metals. The liquid is defined not only as a liquid as a substance but also as a substance formed by dissolving, dispersing, or mixing particles of functional materials composed of solids such as pigments and metal particles in a solvent. Representative examples of liquids include inks or liquid crystals as described in the above embodiments. Here, inks include various liquid compositions such as general water-based inks, oil-based inks, gel inks, and hot-melt inks. Specific examples of liquid ejection devices include those that eject liquids containing electrode materials, color materials, and other materials used in the manufacture of liquid crystal displays, electroluminescent displays, surface-emitting displays, and color filters in a dispersed or dissolved manner. Liquid ejection devices can also be devices that eject biological organic matter used in biochip manufacturing, devices used as precision pipettes to eject liquids as samples, dyeing and printing devices, micro-dispensers, etc. Liquid ejection devices can also be devices that use needles to eject lubricating oil into precision machinery such as watches and cameras, or devices that eject transparent resin liquids such as UV-curable resins onto substrates to form micro-hemispherical lenses and optical lenses used in optical communication components. Liquid ejection devices can also be devices that eject acidic or alkaline etching solutions to etch substrates.

[0183] Postscript

[0184] The following text describes the technical concepts and effects that can be grasped from the above-described embodiments and variations.

[0185] (A) A liquid ejection device comprises: a liquid ejection head capable of ejecting liquid from a nozzle; a first storage section for storing the liquid; a second storage section connected to the first storage section via a communication channel and supplied with the liquid from the first storage section; a supply channel for supplying the liquid from the second storage section to the liquid ejection head; a recovery channel for recovering the liquid from the liquid ejection head back to the first storage section; a first valve disposed in the communication channel and capable of opening and closing the communication channel; a second valve disposed in the supply channel and capable of opening and closing the supply channel; a pressurization section for pressurizing the second storage section; and a control section, wherein the first storage section, the supply channel, the liquid ejection head, the recovery channel, the second storage section, and the communication channel constitute a system capable of circulating the liquid. The control unit executes a discharge cycle and a non-discharge cycle. The discharge cycle involves closing the communication channel by the first valve and closing the supply channel by the second valve, and opening the supply channel by the second valve after pressurizing the second storage unit to a first pressure using the pressurizing unit. This allows the liquid to circulate within the circulation path while being discharged from the nozzle. The non-discharge cycle involves closing the communication channel by the first valve and closing the supply channel by the second valve, and opening the supply channel by the second valve after pressurizing the second storage unit to a second pressure lower than the first pressure using the pressurizing unit. This allows the liquid to circulate within the circulation path without being discharged from the nozzle.

[0186] According to this structure, multiple processes, such as discharge cycles and non-discharge cycles, can be implemented using a shared circulation path. Therefore, compared to implementing multiple processes using different paths, the complexity of the liquid flow path can be reduced. Furthermore, according to this structure, in both discharge and non-discharge cycles, the connection channel closed by the first valve and the supply channel closed by the second valve are implemented before the supply channel is opened by the second valve, and pressurization is performed in the second storage section by the pressurization unit. Therefore, compared to the case where pressurization in the second storage section is performed after the supply channel is opened by the second valve, the liquid can circulate in the circulation path earlier in both discharge and non-discharge cycles. Therefore, the time required for multiple processes, such as discharge and non-discharge cycles, can be shortened.

[0187] (B) In the liquid dispensing device, the control unit is capable of performing a filling cycle, which involves closing the communication channel by the first valve and closing the supply channel by the second valve, and opening the supply channel by the second valve after pressurizing the second storage unit to a pressure less than the first pressure and greater than the second pressure, i.e., a third pressure, using the pressurizing unit, thereby dispensing the liquid from the nozzle while filling the circulation path with the liquid.

[0188] According to this structure, a shared circulation path can be used for the discharge cycle, the non-discharge cycle, and the filling cycle, which are treated differently from them. Therefore, the complexity of the liquid flow path can be further suppressed. Furthermore, according to this structure, in the filling cycle, the connection channel closed by the first valve and the supply channel closed by the second valve are performed before the supply channel is opened by the second valve, and pressurization is performed in the second storage section by the pressurization unit. Therefore, compared to the case where pressurization in the second storage section is performed after the supply channel is opened by the second valve, the liquid can circulate in the circulation path earlier in the filling cycle. Therefore, the time required for the filling cycle can be shortened.

[0189] (C) In the liquid ejection device, after the control unit opens the supply channel by the second valve, the pressurization unit pressurizes the second storage unit to reduce the pressure drop in the second storage unit caused by the opening of the supply channel by the second valve.

[0190] According to this structure, compared to the case where pressurization of the second storage compartment is not performed by the pressurizing unit after the supply channel is opened by the second valve, the pressure drop in the second storage compartment caused by the opening of the supply channel by the second valve can be reduced. Therefore, the pressure in the second storage compartment required to maintain the circulation of liquid in the circulation path and the discharge of liquid from the nozzle can be maintained.

[0191] (D) In ​​the liquid ejection device, the first valve is a one-way valve, and the communication channel is closed in conjunction with the pressurization of the second storage unit by the pressurization unit.

[0192] According to this structure, a drive mechanism for actuating the first valve is no longer required. Therefore, it is possible to suppress the increase in the number of components mounted on the liquid ejection device.

[0193] (E) The liquid ejection device also includes a temperature detection unit that detects the temperature of the environment in which the liquid ejection device is used, i.e., the ambient temperature. After a predetermined time has elapsed since the supply channel has been opened using the second valve, the control unit closes the supply channel. When the ambient temperature detected by the temperature detection unit is a first temperature, the predetermined time is set to be longer than when the ambient temperature is a second temperature higher than the first temperature.

[0194] The lower the ambient temperature, the higher the viscosity of the liquid. Therefore, there is a possibility that the flow rate of the liquid flowing in the supply channel, which accompanies the opening of the supply channel by the second valve, will vary depending on the ambient temperature. According to this structure, when the ambient temperature is a first temperature, the predetermined time is set to be longer compared to when the ambient temperature is a second temperature higher than the first temperature. Therefore, it is possible to suppress the possibility that the flow rate of the liquid flowing in the circulation path will increase or decrease with changes in ambient temperature.

[0195] (F) In the liquid ejection device, an inlet is formed on the first storage section, the inlet being for the liquid in the recovery channel to flow into, and the inlet being located below the center of the first storage section.

[0196] According to this structure, the liquid flowing in the recovery channel flows into the first storage section through the inlet. Since the inlet is located below the center of the first storage section, the liquid stored in the first storage section is agitated by the liquid flowing in from the inlet. Therefore, sedimentation in the first storage section can be restored.

[0197] (G) The liquid ejection device also includes a third valve, which is disposed in the recovery channel and is capable of opening and closing the recovery channel. The control unit is capable of changing the closing and opening of the recovery channel by the third valve.

[0198] According to this structure, it is possible to switch whether the liquid flowing from the recovery channel to the first storage section can be switched.

[0199] (H) In a control method for a liquid ejection device, the liquid ejection device comprises: a liquid ejection head capable of ejecting liquid from a nozzle; a first storage unit for storing the liquid; a second storage unit connected to the first storage unit via a communication channel and supplied with the liquid from the first storage unit; a supply channel for supplying the liquid from the second storage unit to the liquid ejection head; a recovery channel for recovering the liquid from the liquid ejection head back to the first storage unit; a first valve disposed in the communication channel and capable of opening and closing the communication channel; a second valve disposed in the supply channel and capable of opening and closing the supply channel; and a pressurization unit for pressurizing the second storage unit, wherein the first storage unit, the supply channel, the liquid ejection head, the recovery channel, the second storage unit, and the communication channel constitute a circulation system capable of circulating the liquid. In the control method of the liquid ejection device, when implementing a discharge cycle in which the liquid is discharged from the nozzle and circulated within the circulation path, the communication channel is closed by the first valve and the supply channel is closed by the second valve. After pressurizing the second storage unit to a first pressure greater than the meniscus breaking pressure of the nozzle using the pressurizing unit, the supply channel is opened by the second valve. In the case of a non-discharge cycle in which the liquid is circulated within the circulation path without being discharged from the nozzle, the communication channel is closed by the first valve and the supply channel is closed by the second valve. After pressurizing the second storage unit to a second pressure less than the meniscus breaking pressure using the pressurizing unit, the supply channel is opened by the second valve.

[0200] According to this method, multiple processes, such as discharge cycles and non-discharge cycles, can be implemented using a shared circulation path. Therefore, compared to implementing multiple processes using different paths, the complexity of the liquid flow path can be suppressed. Furthermore, according to this method, in both discharge and non-discharge cycles, the connection channel closed by the first valve and the supply channel closed by the second valve are implemented before the supply channel is opened by the second valve, and pressurization is performed in the second storage section by the pressurization unit. Therefore, compared to the case where pressurization in the second storage section is performed after the supply channel is opened by the second valve, the liquid can circulate in the circulation path earlier in both discharge and non-discharge cycles. Therefore, the time required for multiple processes, such as discharge and non-discharge cycles, can be shortened.

[0201] (I) In the control method of the liquid ejection device, the liquid ejection device further includes a temperature detection unit, which detects the temperature of the environment in which the liquid ejection device is used, i.e., the ambient temperature. After a predetermined time has elapsed since the supply channel has been opened using the second valve, the supply channel is closed. When the ambient temperature detected by the temperature detection unit is a first temperature, the predetermined time is set to be longer than when the ambient temperature is a second temperature higher than the first temperature.

[0202] The lower the ambient temperature, the higher the viscosity of the liquid. Therefore, there is a possibility that the flow rate of the liquid flowing in the supply channel, accompanying the opening of the supply channel by the second valve, may vary depending on the ambient temperature. According to this method, when the ambient temperature is a first temperature, the predetermined time is set to be longer compared to when the ambient temperature is a second temperature higher than the first temperature. Therefore, it is possible to suppress the possibility that the flow rate of the liquid flowing in the circulation path may increase or decrease with changes in ambient temperature.

[0203] Symbol Explanation

[0204] P1…First pressure; P2…Second pressure; P3…Third pressure; 11…Liquid ejection device; 11a…Circulation path; 19…Control unit; 22…Nozzle; 23…Liquid ejection head; 33…First storage unit; 33a…Inlet; 34…Connecting channel; 35…Second storage unit; 36…First valve; 37…Supply channel; 38…Second valve; 39…Recovery channel; 40…Third valve; 47…Pressure unit; 80…Temperature detection unit.

Claims

1. A liquid ejection device, characterized in that, have: A liquid ejector head that can eject liquid from a nozzle; A first storage unit stores the liquid; The second storage unit is connected to the first storage unit via a communication channel, and the liquid is supplied from the first storage unit; A supply channel that supplies the liquid from the second storage section to the liquid nozzle; A recovery channel that recovers the liquid from the liquid nozzle back to the first storage section; A first valve is disposed in the communication channel and is capable of opening and closing the communication channel; A second valve is disposed in the supply channel and is capable of opening and closing the supply channel; A pressurizing section that pressurizes the second storage section; Control Department The first storage unit, the supply channel, the liquid nozzle, the recovery channel, the second storage unit, and the connecting channel constitute a circulation path capable of circulating the liquid. The control unit is capable of executing discharge cycles and non-discharge cycles. The discharge circulation is achieved by closing the communication channel via the first valve and the supply channel via the second valve, and by opening the supply channel via the second valve after pressurizing the second storage unit to a first pressure using the pressurizing unit. This allows the liquid to circulate within the circulation path while being discharged from the nozzle. The non-discharge circulation is achieved by closing the communication channel by the first valve and the supply channel by the second valve, and by opening the supply channel by the second valve after pressurizing the second storage section to a second pressure less than the first pressure using the pressurizing section. This allows the liquid to circulate within the circulation path without being discharged from the nozzle.

2. The liquid ejection device as described in claim 1, characterized in that, The control unit is capable of performing a filling cycle, which involves closing the communication channel by the first valve and closing the supply channel by the second valve, and after pressurizing the second storage unit to a pressure less than the first pressure and greater than the second pressure (i.e., a third pressure) using the pressurizing unit, opening the supply channel using the second valve, thereby filling the liquid in the circulation path while discharging the liquid from the nozzle.

3. The liquid ejection device as described in claim 1, characterized in that, After the control unit opens the supply channel via the second valve, it pressurizes the second storage unit via the pressurization unit to reduce the pressure drop in the second storage unit caused by the opening of the supply channel via the second valve.

4. The liquid ejection device as described in claim 1, characterized in that, The first valve is a one-way valve, and the communication channel is closed in conjunction with the pressurization of the second storage unit by the pressurizing unit.

5. The liquid ejection device as described in claim 1, characterized in that, It also includes a temperature detection unit that detects the temperature of the environment in which the liquid spraying device is used, i.e., the ambient temperature. After a predetermined time has elapsed since the supply channel has been opened using the second valve, the control unit closes the supply channel. When the ambient temperature detected by the temperature detection unit is a first temperature, the predetermined time is set to be longer than when the ambient temperature is a second temperature higher than the first temperature.

6. The liquid ejection device as claimed in claim 1, characterized in that, An inlet is formed on the first storage section, the inlet allowing the liquid in the recovery channel to flow in. The inlet is located below the center of the first storage section.

7. The liquid ejection device as claimed in claim 1, characterized in that, It also includes a third valve, which is disposed in the recovery flow channel and is capable of opening and closing the recovery flow channel. The control unit can change the closing and opening of the recovery channel by the third valve.

8. A control method for a liquid ejection device, characterized in that, The liquid ejection device includes: A liquid ejector head that can eject liquid from a nozzle; A first storage unit stores the liquid; The second storage unit is connected to the first storage unit via a communication channel, and the liquid is supplied from the first storage unit; A supply channel that supplies the liquid from the second storage section to the liquid nozzle; A recovery channel that recovers the liquid from the liquid nozzle back to the first storage section; A first valve is disposed in the communication channel and is capable of opening and closing the communication channel; A second valve is disposed in the supply channel and is capable of opening and closing the supply channel; The pressurization unit pressurizes the second storage section. The first storage unit, the supply channel, the liquid nozzle, the recovery channel, the second storage unit, and the connecting channel constitute a circulation path capable of circulating the liquid. In the control method of the liquid ejection device, In the case of performing a discharge cycle where the liquid is discharged from the nozzle while circulating within the circulation path, the communication channel is closed by the first valve and the supply channel is closed by the second valve. After pressurizing the second storage section to a first pressure greater than the meniscus breaking pressure of the nozzle using the pressurizing section, the supply channel is opened using the second valve. In the case of implementing a non-discharge cycle in which the liquid is circulated within the circulation path without being discharged from the nozzle, the communication channel is closed by the first valve and the supply channel is closed by the second valve. After the second storage section is pressurized to a second pressure less than the meniscus breaking pressure by the pressurizing section, the supply channel is opened by the second valve.

9. The control method for the liquid ejection device as described in claim 8, characterized in that, The liquid ejection device also includes a temperature detection unit, which detects the temperature of the environment in which the liquid ejection device is used, i.e., the ambient temperature. After a predetermined time has elapsed since the supply channel has been opened using the second valve, the supply channel is closed. When the ambient temperature detected by the temperature detection unit is a first temperature, the predetermined time is set to be longer than when the ambient temperature is a second temperature higher than the first temperature.

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