Variable pressure unit and liquid ejecting apparatus

Abstract

The invention relates to a pressure variable unit and a liquid ejecting apparatus. The pressure variable unit changes the pressure of a plurality of connection objects, and is provided with: a motor; the pump is connected with the motor and is driven by the power of the motor; a switching unit (94) for switching the connection between the plurality of connection objects and the pump by means of the power of the motor; and a transmission part located between the motor and the switching part, the transmission part being configured so as not to transmit power from the motor to the switching part when the motor rotates in the forward direction, but to transmit power from the motor to the switching part when the motor rotates in the reverse direction.

Description

Technical Field

[0001] The present invention relates to a pressure variable unit and a liquid ejection device. Background Art

[0002] Patent Document 1 describes a liquid ejection device including a pressure variable unit that changes the pressure of a plurality of connection objects. The pressure variable unit includes a pump that changes the pressure of a plurality of connection objects and a switching unit that switches the connection between the plurality of connection objects and the pump. By connecting an arbitrary connection object to the pump through the switching unit, the pressure of the connection object is changed by the pump.

[0003] Patent Document 1: Japanese Unexamined Patent Application Publication No. 2023-59392

[0004] Such a pressure variable unit separately includes a motor for driving the pump and a motor for driving the switching unit. In this case, the pressure variable unit and the liquid ejection device may become large-sized. Summary of the Invention

[0005] A pressure variable unit that solves the above technical problem changes the pressure of a plurality of connection objects and includes: a motor; a pump connected to the motor and driven by the power of the motor; a switching unit that switches the connection between the plurality of connection objects and the pump using the power of the motor; and a transmission unit located between the motor and the switching unit. The transmission unit is configured to not transmit power from the motor to the switching unit when the motor rotates forward, and to transmit power from the motor to the switching unit when the motor rotates backward.

[0006] A liquid ejection device that solves the above technical problem includes: a liquid ejection unit that ejects liquid; and a liquid supply unit that supplies liquid to the liquid ejection unit. The liquid supply unit includes: a supply flow path through which liquid flows toward the liquid ejection unit; and the above pressure variable unit. At least one of the liquid supply unit and the liquid ejection unit has a housing portion that houses liquid. The housing portion has a film member that divides the inside of the housing portion into an air chamber and a liquid chamber. The plurality of connection objects include the housing portion, and the pressure variable unit changes the pressure of the air chamber. Brief Description of the Drawings

[0007] Figure 1 is a perspective view showing an example of a liquid ejection device.

[0008] Figure 2 is a front view schematically showing the internal configuration of the liquid ejection device.

[0009] Figure 3 is a cross-sectional view showing an example of the housing portion.

[0010] Figure 4 is a perspective view showing the internal structure of the liquid ejecting device.

[0011] Figure 5 is a perspective view observed from an angle different from that of Figure 4 and

[0012] Figure 6 is a perspective view observed from an angle different from that of Figure 4 and Figure 5 and

[0013] Figure 7 is a perspective view observed from an angle different from that of Figure 4 and Figure 5 and Figure 6 and

[0014] Figure 8 is a perspective view of the frame and the first pump unit.

[0015] Figure 9 is a perspective view with the first pump unit removed from the state shown in Figure 8 and

[0016] Figure 10 is a perspective view of the liquid ejecting unit.

[0017] Figure 11 is a cross-sectional view of the flow portion.

[0018] Figure 12 is a perspective view of the flow path pump.

[0019] Figure 13 is a cross-sectional view schematically showing the flow path pump.

[0020] Figure 14 is a perspective view of the first pump unit.

[0021] Figure 15 is a perspective view of the state where the mounting member is mounted on the frame.

[0022] Figure 16 is a front view of the state where the first pump unit is mounted on the frame.

[0023] Figure 17 is a front view of the state where the insertion portion is removed from the frame.

[0024] Figure 18 is a perspective view observed from an angle different from that of Figure 14 and

[0025] Figure 19 is a perspective view showing the internal structure of the first pump unit.

[0026] Figure 20It is a top view of the flow path component.

[0027] Figure 21 It is a view of the transmission gear and the coupling gear observed axially.

[0028] Figure 22 It is a perspective view showing the one-way clutch.

[0029] Figure 23 It is a perspective view showing the second pump unit.

[0030] Figure 24 It is a block diagram of the liquid ejection unit and the liquid supply unit.

[0031] Figure 25 It is a perspective view of the supply flow path and the air flow path.

[0032] Figure 26 It is a front view of the supply flow path and the air flow path.

[0033] Figure 27 It is a cross-sectional view of the supply flow path and the air flow path.

[0034] Figure 28 It is a perspective view of the bundled body.

[0035] Figure 29 It is a schematic diagram of the state where the liquid ejection unit is in the standby position.

[0036] Figure 30 It is a schematic diagram of the state where the liquid ejection unit is between the standby position and the return position.

[0037] Figure 31 It is a schematic diagram of the state where the liquid ejection unit is in the return position.

[0038] Figure 32 It is a table showing the operation of the pressure variable unit.

[0039] Figure 33 It is a perspective view showing a modified example of the flow path component.

[0040] Figure 34 It is a schematic diagram showing an example of the liquid ejection device.

[0041] Figure 35 It is a cross-sectional view showing an example of the accommodation part.

[0042] Figure 36 It is a cross-sectional view showing an example of the flow part.

[0043] Figure 37 It is a graph showing the change in the applied voltage.

[0044] Figure 38It is a graph showing the pressure change of the pressurized air chamber.

[0045] Figure 39 It is a graph showing the pressure change of the pressurized liquid chamber.

[0046] Explanation of reference numerals

[0047] 11: Liquid ejection device, 12: Housing, 13: Discharge port, 14: Reading unit, 15: Operation unit, 16: Discharge tray, 17: Medium accommodation part, 18: Assembly part, 19: Assembly body, 20: Liquid container, 21: Medium support part, 22: Liquid ejection unit, 23: Ejection part, 24: Nozzle surface, 25: Nozzle, 26: Moving body, 27: Flow part, 28: Accommodation part, 29: Membrane component, 30: Liquid supply unit, 31: Moving shaft, 32: Frame, 33: Support plate, 34: Support part, 35: First support piece, 36: Second support piece, 37: Installation part, 38: First installation piece, 39: Second installation piece, 40: Fixing hole, 41: Fixing component, 42: Control part, 51: Adjusting valve, 52: Opening and closing valve, 53: Pressurizing part, 54: Ejection joint, 55: Flow component, 56: Flow blocking membrane, 57: Valve part, 58: Action part, 59: Rod, 60: Shaft part, 61: First part, 62: Second part, 63: Pressurizing membrane, 64: Pressurizing component, 71: Flow path pump, 72: Pump component, 73: Pump inlet pipe, 74: Pump outlet pipe, 75: Pump air pipe, 76: Diaphragm, 77: Pressing component, 81: Pressure variable unit, 82: First pump unit, 83: Second pump unit, 84: Installation component, 85: Installation plate, 86: Contact part, 87: First contact piece, 88: Second contact piece, 89: Insertion part, 90: Insertion groove, 91: Base component, 92: First motor, 93: First pump, 94: Switching part, 95: Flow path component, 96: Flow path substrate, 97: Cover component, 98: Pump port, 99: Open port, 100: Pressurizing port, 101: Flow blocking port, 102: Pump pipe, 103: Flow path pump pipe, 104: Open pipe, 105: Pressurizing pipe, 106: Flow blocking pipe, 107: Selection valve, 108: Valve seat, 109: Pump valve, 110: Open valve, 111: Pressurizing valve, 112: Flow blocking valve, 113: Pump valve rod, 114: Open valve rod, 115: Pressurizing valve rod, 116: Flow blocking valve rod, 117: Cam unit, 118: Pump cam, 119: Open cam, 120: Pressurizing cam, 121: Flow blocking cam, 122: Cam shaft, 123: First transmission part, 124: Output pinion, 125: Output belt, 126: Output gear, 127: Transmission gear, 128: Connecting gear, 129: Relay gear, 130: Cam gear, 131: Transmission shaft, 132: Transmission support part, 133: Connecting support part, 134: One-way clutch, 135: Detection part, 136: Photoelectric sensor unit, 137: Light interrupter, 138: Shielding plate, 139: Rotary encoder, 140: Encoder, 141: Scale, 142: Second motor, 143: Second pump, 144: Atmospheric opening part, 145: Atmospheric opening base, 146: Atmospheric opening valve, 147: Atmospheric opening rod, 148: Second transmission part, 149: Driving pinion150: drive belt, 151: drive gear, 152: connecting gear, 153: connecting shaft, 154: friction clutch, 155: atmosphere-open cam, 161: supply flow path, 162: air flow path, 163: first fixed part, 164: first movable part, 165: second fixed part, 166: second movable part, 167: guide member, 168: relay joint, 169: first flexible member, 170: second flexible member, 171: first extension part, 172: first bending part, 173: second extension part, 174: second bending part, 175: bundled body, 176: holding part, 177: supporting part, 178: arm, 179: pulley, 180: flange, 181: inclined surface, 186: switching body, 187: switching base material, 188: rotating body, A1: moving area, C1: liquid chamber, C2: air chamber, C3: flow-blocking space, C4: pressurizing space, C5: flow-blocking liquid chamber, C6: flow-blocking air chamber, C7: pressurizing liquid chamber, C8: pressurizing air chamber, C11: pump space, C12: pump liquid chamber, C13: pump air chamber, D1: scanning direction, H1: inlet, H2: outlet, H3: air port, H4: flow-blocking inlet, H5: flow-blocking outlet, H6: flow-blocking air port, H7: pressurizing inlet, H8: pressurizing outlet, H9: pressurizing air port, H11: pump inlet, H12: pump outlet, H13: pump air port, L1: center line, M1: medium, P1: pump passage, P2: open passage, P3: pressurizing passage, P4: flow-blocking passage, P5: conducting passage, 211: liquid ejection device, 212: liquid ejection unit, 213: liquid container, 214: ejection part, 215: nozzle surface, 216: nozzle, 217: accommodating part, 218: film member, 221: flow part, 222: regulating valve, 223: on-off valve, 224: pressurizing part, 225: flow member, 226: flow-blocking film, 227: valve part, 228: operating part, 229: rod, 230: shaft part, 231: first part, 232: second part, 233: pressurizing film, 234: pressurizing member, 236: moving body, 241: liquid supply unit, 242: supply flow path, 243: supply valve, 244: flow path pump, 245: diaphragm, 246: pressing member, 247: pressure variable unit, 248: vacuum pump, 249: motor, 250: air flow path, 251: first air valve, 252: second air valve, 253: third air valve, 254: atmosphere-open valve, 256: power supply circuit, 257: control part, C21: liquid chamber, C211: flow path liquid chamber, C212: flow path air chamber, C22: air chamber, C23: flow-blocking space, C24: pressurizing space, C25: flow-blocking liquid chamber, C26: flow-blocking air chamber, C27: pressurizing liquid chamber, C28: pressurizing air chamber, H21: inlet, H22: outlet, H23: air port, H24: flow-blocking inlet,H25: Flow blocking outlet, H26: Flow blocking air port, H27: Pressurized inlet, H28: Pressurized outlet, H29: Pressurized air port, M21: Medium. Detailed implementation

[0048] 1. Embodiment 1

[0049] Hereinafter, an embodiment of a liquid ejection device will be described with reference to the drawings. The liquid ejection device is, for example, an inkjet printer that prints images such as characters and photos by ejecting ink, which is an example of a liquid, onto a medium such as paper or cloth.

[0050] Liquid ejection device

[0051] As Figure 1 shown, the liquid ejection device 11 includes a housing 12. The discharge port 13 is open in the housing 12. The printed medium M1 is discharged from the discharge port 13.

[0052] The liquid ejection device 11 may also include a reading unit 14. The reading unit 14 is configured to read an image recorded on a document. The reading unit 14 is a scanner. The reading unit 14, for example, automatically feeds the placed document and sequentially reads the image. The reading unit 14 is mounted on the housing 12. The reading unit 14 is, for example, mounted on the upper part of the housing 12. In one example, the reading unit 14 is installed so as to be openable and closable with respect to the housing 12. When the reading unit 14 is opened with respect to the housing 12, the inside of the housing 12 is exposed. The user can approach the inside of the housing 12 from the upper part of the housing 12 by opening the reading unit 14.

[0053] The liquid ejection device 11 includes an operation unit 15. The operation unit 15 is an interface for the user to operate the liquid ejection device 11. The operation unit 15 is, for example, a touch panel. The operation unit 15 may also include buttons, levers, switches, etc. The operation unit 15 is, for example, located on the front surface of the housing 12.

[0054] The liquid ejection device 11 may also include a discharge tray 16. The discharge tray 16 receives the printed medium M1. The discharge tray 16 receives the medium M1 discharged from the discharge port 13. The discharge tray 16 extends from the discharge port 13. In one example, the discharge tray 16 extends from the inside of the housing 12 toward the front of the liquid ejection device 11 through the discharge port 13.

[0055] The liquid ejection device 11 includes a medium storage unit 17. The medium storage unit 17 is configured to store the medium M1. The medium storage unit 17 stores the medium M1 before printing. The medium storage unit 17 is a cassette. The medium storage unit 17 is, for example, configured to be insertable and removable with respect to the housing 12.

[0056] The liquid ejection device 11 includes a fitting portion 18. The fitting portion 18 is configured to fit one or more fitting bodies 19 thereto. In one example, four fitting bodies 19 are fitted to the fitting portion 18. The fitting body 19 is a cartridge. The fitting body 19 is configured to be insertable and removable relative to the fitting portion 18, for example.

[0057] As Figure 2 shown, the fitting body 19 is configured to be able to fit a liquid container 20. The liquid container 20 is a container that holds a liquid. The liquid container 20 is, for example, an ink bag. The liquid container 20 is fitted to the fitting portion 18 via the fitting body 19. In one example, four liquid containers 20 are fitted to the fitting portion 18. The four liquid containers 20 may each hold a different liquid. For example, the four liquid containers 20 may each hold cyan ink, magenta ink, yellow ink, and black ink, respectively. By fitting the liquid container 20 to the fitting portion 18, liquid is supplied from the liquid container 20 to the liquid ejection device 11.

[0058] The liquid ejection device 11 includes a medium support portion 21. The medium support portion 21 supports the medium M1 conveyed from the medium storage portion 17. The medium support portion 21 supports the medium M1 onto which liquid is being ejected. The medium support portion 21 supports the medium M1 during printing.

[0059] The liquid ejection device 11 includes a liquid ejection unit 22. The liquid ejection unit 22 is configured to eject liquid onto the medium M1. The liquid ejection unit 22 ejects liquid onto the medium M1 supported by the medium support portion 21. The liquid ejection unit 22 is configured to be supplied with liquid from the liquid container 20.

[0060] The liquid ejection unit 22 has an ejection portion 23. The ejection portion 23 has a nozzle surface 24. The nozzle surface 24 is a surface opposed to the medium M1. One or more nozzles 25 are open on the nozzle surface 24. The ejection portion 23 ejects liquid from the nozzles 25.

[0061] The liquid ejection unit 22 is configured to move in the scanning direction D1. Specifically, the liquid ejection unit 22 is configured to move in the scanning direction D1 and the opposite direction thereof. The liquid ejection unit 22 reciprocates on the medium M1. Thereby, the liquid ejection unit 22 can eject liquid over the entire width of the medium M1. In one example, the liquid ejection unit 22 is a serial head. The liquid ejection unit 22 may also be a line head capable of ejecting liquid over the entire width of the medium M1 at once.

[0062] The liquid ejection unit 22 may also have a moving body 26. The moving body 26 mounts the ejection portion 23. The moving body 26 moves in the scanning direction D1 within the housing 12. Specifically, the moving body 26 moves in the scanning direction D1 and the opposite direction thereof. The moving body 26 moves within the moving region A1. The moving region A1 is a region including the region on the medium support portion 21.

[0063] The moving body 26 moves between a standby position and a turning-back position within the moving area A1. The standby position is the position where the moving body 26 stands by. For example, when the liquid ejection unit 22 does not eject liquid onto the medium M1, the moving body 26 is located at the standby position. The turning-back position is the position where the moving body 26 turns back the movement from the scanning direction D1 to the opposite direction. The standby position and the turning-back position are positions at the ends of the moving area A1. As an example, in Figure 2 , the moving body 26 is located at the turning-back position.

[0064] The liquid ejection unit 22 has a flow portion 27. The liquid supplied to the ejection portion 23 flows in the flow portion 27. The flow portion 27 is connected to the ejection portion 23. The flow portion 27 is located between the liquid container 20 and the ejection portion 23. In one example, the flow portion 27 is mounted on the moving body 26. The flow portion 27 will be described later.

[0065] The liquid ejection device 11 includes one or more accommodating portions 28. In one example, the liquid ejection device 11 includes a plurality of accommodating portions 28. The accommodating portion 28 is configured to accommodate liquid. The accommodating portion 28 is connected to the ejection portion 23. The accommodating portion 28 may be directly connected to the ejection portion 23 or indirectly connected to the ejection portion 23 via other components. The liquid accommodated in the accommodating portion 28 is supplied to the ejection portion 23. The accommodating portion 28 is located between the liquid container 20 and the ejection portion 23. The accommodating portion 28 accommodates liquid between the liquid container 20 and the ejection portion 23. The accommodating portion 28 is, for example, an on-off valve 52, a pressurizing portion 53, a flow path pump 71, and the like. The on-off valve 52, the pressurizing portion 53, and the flow path pump 71 will be described later.

[0066] Based on Figure 3 , a common configuration of the accommodating portion 28 will be described. The accommodating portion 28 has a film member 29. The film member 29 is a flexible member. The film member 29 can be deformed. The film member 29 divides the inside of the accommodating portion 28 into a liquid chamber C1 and an air chamber C2. The liquid chamber C1 is a space for accommodating liquid. The liquid chamber C1 communicates with the ejection portion 23. The air chamber C2 is a space for accommodating air. The air chamber C2 communicates with a pressure variable unit 81 described later. The film member 29 separates the liquid chamber C1 and the air chamber C2. The film member 29 constitutes the wall surfaces of the liquid chamber C1 and the air chamber C2. The film member 29 deforms according to the pressure in the liquid chamber C1 and the pressure in the air chamber C2. When the film member 29 deforms, the volumes of the liquid chamber C1 and the air chamber C2 change.

[0067] A plurality of openings are formed in the accommodating portion 28. Liquid and air are supplied to the accommodating portion 28 or discharged from the accommodating portion 28 through the plurality of openings. In one example, an inlet port H1, an outlet port H2, and an air port H3 are open to the accommodating portion 28. The inlet port H1 communicates with the liquid chamber C1. Liquid flows into the liquid chamber C1 through the inlet port H1. The outlet port H2 communicates with the liquid chamber C1. Liquid flows out of the liquid chamber C1 through the outlet port H2. The air port H3 communicates with the air chamber C2. Air is supplied to the air chamber C2 or discharged from the air chamber C2 through the air port H3. That is, the air chamber C2 is pressurized or depressurized through the air port H3. When the air chamber C2 is pressurized, the membrane member 29 deforms in a manner that increases the volume of the air chamber C2. In other words, the membrane member 29 deforms in a manner that decreases the volume of the liquid chamber C1. As a result, liquid flows out of the liquid chamber C1 through the outlet port H2. When the air chamber C2 is depressurized, the membrane member 29 deforms in a manner that decreases the volume of the air chamber C2. In other words, the membrane member 29 deforms in a manner that increases the volume of the liquid chamber C1. As a result, liquid flows into the liquid chamber C1 through the inlet port H1.

[0068] As Figure 4 , Figure 5 , Figure 6 and Figure 7 shown, the liquid ejection device 11 includes a liquid supply unit 30. The liquid supply unit 30 is configured to supply liquid to the liquid ejection unit 22. The liquid supply unit 30 supplies liquid to the ejection portion 23. The liquid supply unit 30 supplies liquid from the liquid container 20 to the ejection portion 23. The liquid supply unit 30 is connected to the liquid ejection unit 22. The liquid supply unit 30 is connected to the fitting portion 18. The liquid supply unit 30 is connected to the liquid container 20 via the fitting portion 18. The liquid supply unit 30 will be described later.

[0069] At least one of the liquid ejection unit 22 and the liquid supply unit 30 has an accommodating portion 28. The liquid ejection unit 22 may have an accommodating portion 28, and the liquid supply unit 30 may also have an accommodating portion 28. It is possible that only the liquid ejection unit 22 has an accommodating portion 28, or only the liquid supply unit 30 has an accommodating portion 28, or both the liquid ejection unit 22 and the liquid supply unit 30 have an accommodating portion 28. In one example, both the liquid ejection unit 22 and the liquid supply unit 30 have an accommodating portion 28.

[0070] The liquid ejection unit 22 and the liquid supply unit 30 each have one or more accommodating portions 28. The liquid ejection unit 22 and the liquid supply unit 30 may each have one accommodating portion 28, or may each have a plurality of accommodating portions 28. It is also possible that one of the liquid ejection unit 22 and the liquid supply unit 30 has one accommodating portion 28 and the other has a plurality of accommodating portions 28.

[0071] The accommodating portion 28 is provided in the liquid ejection unit 22 or the liquid supply unit 30. A plurality of accommodating portions 28 are respectively provided in the liquid ejection unit 22 or the liquid supply unit 30. The plurality of accommodating portions 28 may also include one or more accommodating portions 28 provided in the liquid ejection unit 22 and one or more accommodating portions 28 provided in the liquid supply unit 30.

[0072] The liquid ejection device 11 may also include a moving shaft 31. The moving shaft 31 is a shaft that supports the moving body 26. The moving shaft 31 extends in the scanning direction D1. The moving shaft 31 guides the moving body 26. The moving body 26 moves along the moving shaft 31.

[0073] The liquid ejection device 11 includes a frame 32. The frame 32 supports the liquid supply unit 30. Specifically, the frame 32 supports the pressure variable unit 81. More specifically, the frame 32 supports a pump unit described later. In one example, the frame 32 supports a first pump unit 82 described later.

[0074] As Figure 8 and Figure 9 shown, the frame 32 has a support plate 33. The support plate 33 faces the first pump unit 82. The support plate 33 extends in a direction perpendicular to the scanning direction D1.

[0075] The frame 32 has one or more support portions 34. In one example, the frame 32 has two support portions 34. The support portion 34 is a portion that supports the first pump unit 82. The support portion 34 extends from the support plate 33.

[0076] The support portion 34 has a first support piece 35 and a second support piece 36. The first support piece 35 extends from the support plate 33. The first support piece 35 extends perpendicularly from the support plate 33. The first support piece 35 extends in a manner approaching the first pump unit 82. The second support piece 36 extends from the first support piece 35. The second support piece 36 extends from the front end of the first support piece 35. The second support piece 36 extends perpendicularly from the first support piece 35. The second support piece 36 extends upward.

[0077] The frame 32 has a mounting portion 37. The mounting portion 37 is a portion for mounting the first pump unit 82. The mounting portion 37 has a first mounting piece 38 and a second mounting piece 39. In one example, the mounting portion 37 has one first mounting piece 38 and two second mounting pieces 39. The mounting portion 37 is located at a position higher than the support portion 34.

[0078] The first mounting piece 38 extends from the support plate 33. The first mounting piece 38 extends vertically from the support plate 33. The first mounting piece 38 extends in a manner close to the first pump unit 82. The second mounting piece 39 extends from the first mounting piece 38. The second mounting piece 39 extends from the front end of the first mounting piece 38. The second mounting piece 39 extends vertically from the first mounting piece 38. The second mounting piece 39 extends upward.

[0079] The fixing hole 40 opens in the mounting portion 37. The fixing hole 40 is a hole that penetrates the mounting portion 37 vertically. The fixing hole 40 opens in the first mounting piece 38. In one example, the fixing hole 40 is located between the two second mounting pieces 39. The fixing member 41 described later is inserted into the fixing hole 40. Thus, the first pump unit 82 is fixed to the mounting portion 37.

[0080] The liquid ejecting device 11 includes a fixing member 41. The fixing member 41 is a member that fixes the liquid supply unit 30 to the frame 32. Specifically, the fixing member 41 fixes the pressure variable unit 81 to the frame 32. More specifically, the fixing member 41 fixes the pump unit to the frame 32. In one example, the fixing member 41 fixes the first pump unit 82 to the frame 32. The fixing member 41 is, for example, a screw.

[0081] The fixing member 41 is configured to be detachable from above with respect to the pressure variable unit 81 and the frame 32. In one example, the fixing member 41 is inserted into the fixing hole 40 from above. Therefore, the user can detach and attach the fixing member 41 from above. For example, when the reading unit 14 is opened with respect to the housing 12, the fixing member 41 is exposed. Therefore, the user can remove the first pump unit 82 from above.

[0082] As Figure 2 shown, the liquid ejecting device 11 includes a control unit 42. The control unit 42 controls the liquid supply unit 30. In addition to the liquid supply unit 30, the control unit 42 may also control the liquid ejecting unit 22. The control unit 42 may also comprehensively control the liquid ejecting device 11.

[0083] The control unit 42 may also be composed of one or more processors that execute various processes according to a computer program. The control unit 42 may also be composed of one or more dedicated hardware circuits such as an ASIC that executes at least a part of the various processes. The control unit 42 may also be composed of a circuit including a combination of a processor and a hardware circuit. The processor includes a CPU and memories such as a RAM and a ROM. The memory stores program codes or instructions configured to cause the CPU to execute processes. The memory, that is, the computer-readable medium includes all readable media accessible by a general or dedicated computer.

[0084] Flow portion

[0085] Next, the flow portion 27 will be described.

[0086] The flow unit 27 may also have an adjustment valve 51. The adjustment valve 51 is configured to open and close. The adjustment valve 51 is normally closed. When the adjustment valve 51 is opened, liquid can be supplied to the ejection unit 23. By opening the adjustment valve 51, the liquid flows into the flow unit 27.

[0087] The adjustment valve 51 is configured to adjust the pressure in the ejection unit 23. In one example, the adjustment valve 51 is configured to adjust the pressure in the flow unit 27. The adjustment valve 51 opens and closes based on the pressure in the flow unit 27, thereby adjusting the pressure in the flow unit 27. The adjustment valve 51 adjusts the pressure in the ejection unit 23 by adjusting the pressure in the flow unit 27.

[0088] The adjustment valve 51 is configured to open and close using the differential pressure between the pressure in the ejection unit 23 and the atmospheric pressure. In one example, the adjustment valve 51 opens and closes using the differential pressure between the pressure in the flow unit 27 and the atmospheric pressure. Specifically, the adjustment valve 51 opens when the pressure downstream of itself is below a specified pressure. That is, the adjustment valve 51 opens when the pressure in the flow unit 27 is below a specified pressure. The adjustment valve 51 closes when the pressure in the flow unit 27 is greater than the specified pressure.

[0089] The adjustment valve 51 maintains the pressure in the flow unit 27 at a specified pressure by opening and closing. The adjustment valve 51 maintains the pressure in the ejection unit 23 at a specified pressure by maintaining the pressure in the flow unit 27 at a specified pressure. The operating pressure at which the adjustment valve 51 opens is a specified negative pressure. Therefore, the adjustment valve 51 maintains the pressure in the ejection unit 23 at a specified negative pressure. By maintaining the pressure in the ejection unit 23 at a specified negative pressure, a meniscus is formed at the nozzle 25. By forming a meniscus at the nozzle 25, the ejection unit 23 can eject the liquid well. In the liquid ejection device 11, it is not limited to the adjustment valve 51, and for example, the pressure in the ejection unit 23 can also be maintained at a negative pressure using a head difference.

[0090] The flow unit 27 has one or more accommodating parts 28. The flow unit 27 has, for example, an opening / closing valve 52 and a pressurizing part 53. The opening / closing valve 52 and the pressurizing part 53 are each an example of the accommodating part 28. The opening / closing valve 52 and the pressurizing part 53 are located at a position more downstream than the adjustment valve 51. In the flow unit 27, the liquid is sequentially supplied to the ejection unit 23 through the adjustment valve 51, the opening / closing valve 52, and the pressurizing part 53.

[0091] The on-off valve 52 is connected to the regulating valve 51. The on-off valve 52 is connected to the pressurizing unit 53. The on-off valve 52 is connected to the ejection unit 23 via the pressurizing unit 53. The on-off valve 52 is configured to open and close. Different from the regulating valve 51, the on-off valve 52 is configured to open and close arbitrarily. The on-off valve 52 opens and closes under the control of the control unit 42. The on-off valve 52 opens and closes by changing the pressure in the air chamber C2 of the on-off valve 52. When cleaning the ejection unit 23, the on-off valve 52 closes. Specifically, when the pressurizing unit 53 cleans the ejection unit 23, the on-off valve 52 closes. The on-off valve 52 is normally open.

[0092] The pressurizing unit 53 is connected to the ejection unit 23. The pressurizing unit 53 is configured to pressurize the inside of the ejection unit 23. By changing the pressure in the air chamber C2 of the pressurizing unit 53, the pressurizing unit 53 pressurizes the inside of the ejection unit 23. The pressurizing unit 53 cleans the ejection unit 23 by pressurizing the inside of the ejection unit 23. Specifically, the pressurizing unit 53 causes the liquid to be discharged from the nozzle 25 by pressurizing the inside of the ejection unit 23. Thereby, the thickened liquid, foreign matter, etc. are discharged from the inside of the ejection unit 23. By pressurizing the inside of the ejection unit 23 by the pressurizing unit 53 in a state where the on-off valve 52 is closed, the possibility of the liquid flowing back from the pressurizing unit 53 is reduced. By closing the on-off valve 52, that is, by blocking the flow, the pressurizing unit 53 can effectively pressurize the inside of the ejection unit 23.

[0093] As Figure 10 shown, the flow unit 27 has an ejection joint 54. The ejection joint 54 is connected to the regulating valve 51. In one example, the ejection joint 54 is connected to the regulating valve 51 via a tube. The ejection joint 54 is connected to the liquid supply unit 30. Specifically, the ejection joint 54 is connected to a supply flow path 161 and an air flow path 162 described later. Liquid is supplied to the flow unit 27 through the ejection joint 54 and the regulating valve 51. Air is supplied to the flow unit 27 through the ejection joint 54.

[0094] The flow unit 27 has a flow member 55. The flow member 55 is a member that defines a space for accommodating liquid. The flow member 55 also defines a space for accommodating air. The flow member 55 constitutes the on-off valve 52 and the pressurizing unit 53. The flow member 55 is connected to the regulating valve 51. The flow member 55 is connected to the ejection joint 54. Liquid is supplied to the flow member 55 through the regulating valve 51 and the ejection joint 54. Air is supplied to the flow member 55 through the ejection joint 54. In addition to the on-off valve 52 and the pressurizing unit 53, the flow member 55 may also constitute the regulating valve 51. The flow member 55 may further constitute the ejection joint 54. That is, the regulating valve 51, the on-off valve 52, the pressurizing unit 53, and the ejection joint 54 may be integrally constituted by the flow member 55.

[0095] As Figure 11As shown, the flow component 55 defines a flow-blocking space C3. The flow-blocking space C3 is a space within the on-off valve 52. A flow-blocking flow inlet H4 and a flow-blocking flow outlet H5 are open in the flow component 55. The flow-blocking flow inlet H4 is an example of the flow inlet H1. The flow-blocking flow inlet H4 communicates with the regulating valve 51. The flow-blocking flow outlet H5 is an example of the flow outlet H2. The flow-blocking flow outlet H5 communicates with the pressurizing section 53. A flow-blocking air port H6 is open in the flow component 55. The flow-blocking air port H6 is an example of the air port H3. The flow-blocking air port H6 communicates with the ejection joint 54.

[0096] The flow component 55 defines a pressurizing space C4. The pressurizing space C4 is a space within the pressurizing section 53. A pressurizing flow inlet H7 and a pressurizing flow outlet H8 are open in the flow component 55. The pressurizing flow inlet H7 is an example of the flow inlet H1. The pressurizing flow inlet H7 communicates with the on-off valve 52. The pressurizing flow inlet H7 is an opening shared with the flow-blocking flow outlet H5. The pressurizing flow outlet H8 is an example of the flow outlet H2. The pressurizing flow outlet H8 communicates with the ejection section 23. A pressurizing air port H9 is open in the flow component 55. The pressurizing air port H9 is an example of the air port H3. The pressurizing air port H9 communicates with the ejection joint 54.

[0097] The flow section 27 has a flow-blocking membrane 56. The flow-blocking membrane 56 is mounted on the flow component 55. The flow-blocking membrane 56 is an example of the membrane component 29. The flow-blocking membrane 56 constitutes the on-off valve 52. The flow-blocking membrane 56 divides the flow-blocking space C3 into a flow-blocking liquid chamber C5 and a flow-blocking air chamber C6. The flow-blocking liquid chamber C5 is an example of the liquid chamber C1. The flow-blocking liquid chamber C5 communicates with the flow-blocking flow inlet H4 and the flow-blocking flow outlet H5. The flow-blocking air chamber C6 is an example of the air chamber C2. The flow-blocking air chamber C6 communicates with the flow-blocking air port H6.

[0098] The flow-blocking membrane 56 has a valve portion 57. The valve portion 57 is a portion that blocks the flow-blocking flow inlet H4 or the flow-blocking flow outlet H5. In one example, the valve portion 57 blocks the flow-blocking flow outlet H5. The valve portion 57 blocks the flow-blocking flow outlet H5 by being pressed by a rod 59 described later.

[0099] The flow-blocking membrane 56 has an operating portion 58. The operating portion 58 is a portion that causes the rod 59 to operate. The operating portion 58 is configured to be more deformable than the valve portion 57. In one example, the operating portion 58 is configured to have a smaller elasticity than the valve portion 57. For example, the thickness of the operating portion 58 may also be smaller than the thickness of the valve portion 57. The area of the operating portion 58 facing the flow-blocking air chamber C6 may also be larger than the area of the valve portion 57 facing the flow-blocking air chamber C6.

[0100] When the flow-blocking air chamber C6 is depressurized, the valve portion 57 and the operating portion 58 deform in such a way as to reduce the volume of the flow-blocking air chamber C6. At this time, the operating portion 58 is more deformable than the valve portion 57.

[0101] The flow section 27 has a rod 59. The rod 59 forms the on-off valve 52. The rod 59 is installed on the flow component 55. The rod 59 is located in the flow-blocking space C3. Specifically, the rod 59 is located in the flow-blocking air chamber C6. The rod 59 has, for example, a shaft portion 60. The shaft portion 60 is installed on the flow component 55. The rod 59 is displaced about the shaft portion 60. The rod 59 is displaced in the flow-blocking air chamber C6.

[0102] The rod 59 has a first portion 61 and a second portion 62. The first portion 61 is the portion including one end of the rod 59. The first portion 61 is located at a position in contact with the valve portion 57. The second portion 62 is the portion including the other end of the rod 59. The second portion 62 is located at a position in contact with the actuating portion 58.

[0103] When the flow-blocking air chamber C6 is depressurized, the valve portion 57 deforms in a manner of pushing up the first portion 61. When the flow-blocking air chamber C6 is depressurized, the actuating portion 58 deforms in a manner of pushing up the second portion 62. Since the actuating portion 58 is more easily deformed than the valve portion 57, the force with which the actuating portion 58 pushes up the rod 59 is greater than the force with which the valve portion 57 pushes up the rod 59. Therefore, the rod 59 is displaced in a manner of pressing down the valve portion 57 with the first portion 61. That is, the rod 59 presses the valve portion 57 against the flow-blocking outlet H5. Thereby, the flow-blocking outlet H5 is blocked.

[0104] The flow section 27 has a pressure membrane 63. The pressure membrane 63 is installed on the flow component 55. The pressure membrane 63 is an example of the membrane component 29. The pressure membrane 63 forms the pressurizing section 53. The pressure membrane 63 divides the pressurizing space C4 into a pressurizing liquid chamber C7 and a pressurizing air chamber C8. The pressurizing liquid chamber C7 is an example of the liquid chamber C1. The pressurizing liquid chamber C7 communicates with the pressurizing inlet H7 and the pressurizing outlet H8. The pressurizing air chamber C8 is an example of the air chamber C2. The pressurizing air chamber C8 communicates with the pressurizing air port H9.

[0105] The flow section 27 may also have a pressurizing component 64. The pressurizing component 64 is configured to press the pressure membrane 63. Specifically, the pressurizing component 64 presses the pressure membrane 63 in a manner of reducing the volume of the pressurizing liquid chamber C7. The pressurizing component 64 is located in the pressurizing air chamber C8. The pressurizing component 64 is installed on the flow component 55 and the pressure membrane 63.

[0106] When the pressurized air chamber C8 is depressurized, the pressurizing membrane 63 is displaced in such a way as to reduce the volume of the pressurized air chamber C8. At this time, the pressurizing membrane 63 is displaced in such a way as to increase the volume of the pressurized liquid chamber C7. As a result, liquid flows into the pressurized liquid chamber C7. Specifically, the liquid flows into the pressurized liquid chamber C7 from the ejection section 23, the regulating valve 51, the on-off valve 52, and the like. When the pressurized air chamber C8 is pressurized or opened to the atmosphere, the pressurizing membrane 63 is deformed in such a way as to reduce the volume of the pressurized liquid chamber C7. At this time, the liquid in the pressurized liquid chamber C7 is pressurized. As a result, the liquid is discharged from the nozzle 25.

[0107] Liquid supply unit

[0108] Next, the liquid supply unit 30 will be described.

[0109] As Figure 4 , Figure 5 , Figure 6 and Figure 7 shown, the liquid supply unit 30 is connected to the fitting portion 18. The liquid supply unit 30 is connected to the liquid ejection unit 22.

[0110] The liquid supply unit 30 has a housing portion 28. Specifically, the liquid supply unit 30 has a flow path pump 71. The flow path pump 71 is an example of the housing portion 28. The flow path pump 71 is a so-called diaphragm pump.

[0111] The liquid supply unit 30 has one or more flow path pumps 71. In one example, the liquid supply unit 30 has four flow path pumps 71. The flow path pumps 71 are connected to the fitting portion 18. The flow path pumps 71 are located behind the fitting portion 18. The four flow path pumps 71 are respectively located behind the four liquid containers 20. The flow path pumps 71 are connected to the liquid containers 20 through the fitting portion 18. The four flow path pumps 71 are respectively connected to the four liquid containers 20. The flow path pumps 71 supply liquid from the liquid containers 20 toward the ejection section 23.

[0112] As Figure 12 and Figure 13 shown, the flow path pump 71 has a pump component 72. The pump component 72 defines a pump space C11. The pump component 72 has a pump inlet pipe 73, a pump outlet pipe 74, and a pump air pipe 75. The pump inlet pipe 73 is inserted into the liquid container 20 assembled to the fitting portion 18. The pump inlet pipe 73 is a so-called supply needle. The pump inlet port H11 is opened in the pump inlet pipe 73. The pump inlet port H11 is an example of the inlet port H1. The pump outlet pipe 74 is connected to the supply flow path 161. The pump outlet port H12 is opened in the pump outlet pipe 74. The pump outlet port H12 is an example of the outlet port H2. The pump air pipe 75 is connected to the air flow path 162. The pump air port H13 is opened in the pump air pipe 75. The pump air port H13 is an example of the air port H3.

[0113] AsFigure 13 As shown, the flow path pump 71 has a diaphragm 76 as an example of the membrane component 29. The diaphragm 76 divides the inside of the flow path pump 71 into a pump liquid chamber C12 and a pump air chamber C13. Specifically, the diaphragm 76 divides the pump space C11 into a pump liquid chamber C12 and a pump air chamber C13. The pump liquid chamber C12 is an example of the liquid chamber C1. The pump air chamber C13 is an example of the air chamber C2. The pump liquid chamber C12 communicates with the pump inlet H11 and the pump outlet H12. The pump liquid chamber C12 communicates with the ejection unit 23 via the pump outlet H12. The pump air chamber C13 communicates with the pump air port H13. The pump air chamber C13 communicates with the pressure variable unit 81 via the pump air port H13.

[0114] The flow path pump 71 has a pressing member 77. The pressing member 77 is configured to press the diaphragm 76. Specifically, the pressing member 77 presses the diaphragm 76 in such a way that the volume of the pump liquid chamber C12 becomes smaller. That is, the pressing member 77 presses the diaphragm 76 in such a way as to pressurize the pump liquid chamber C12. The pressing member 77 is located in the pump air chamber C13.

[0115] When the pump air chamber C13 is decompressed, the diaphragm 76 deforms in such a way that the volume of the pump liquid chamber C12 becomes larger. As a result, the liquid flows from the liquid container 20 into the pump liquid chamber C12. When the pump air chamber C13 is pressurized or opened to the atmosphere, the diaphragm 76 deforms in such a way that the volume of the pump liquid chamber C12 becomes smaller. As a result, the liquid flows out from the pump liquid chamber C12 toward the flow unit 27.

[0116] As Figure 4 , Figure 5 , Figure 6 and Figure 7 shown, the liquid supply unit 30 has a pressure variable unit 81. The pressure variable unit 81 is connected to a plurality of connection objects. The plurality of connection objects includes one or more accommodation parts 28. That is, the pressure variable unit 81 is connected to one or more accommodation parts 28. In one example, the plurality of connection objects includes a plurality of accommodation parts 28. The pressure variable unit 81 is connected to a plurality of accommodation parts 28. Specifically, the pressure variable unit 81 is connected to the on-off valve 52, the pressurizing unit 53, and the flow path pump 71. The plurality of connection objects may also include components other than the accommodation part 28. That is, the pressure variable unit 81 may also be connected to components other than the accommodation part 28.

[0117] The pressure variable unit 81 is configured to change the pressure of the plurality of connection objects. Specifically, the pressure variable unit 81 changes the pressure of one or more of the plurality of connection objects. The pressure variable unit 81 changes the pressure of any of the plurality of connection objects. For example, the pressure variable unit 81 changes the pressure of the accommodation part 28 among the plurality of connection objects. The pressure variable unit 81 changes the pressure of the on-off valve 52, the pressurizing unit 53, the flow path pump 71, etc.

[0118] The pressure variable unit 81 changes the pressure in the air chamber C2. In one example, the pressure variable unit 81 reduces the pressure in the air chamber C2. The pressure variable unit 81 may also increase the pressure in the air chamber C2.

[0119] The pressure variable unit 81 selectively changes the pressure in a plurality of accommodation portions 28. For example, the pressure variable unit 81 changes the pressure in any of the accommodation portions 28 of the on-off valve 52, the pressurizing portion 53, and the flow path pump 71. The pressure variable unit 81 selectively changes the pressure in a plurality of air chambers C2. That is, the pressure variable unit 81 selectively changes the pressure in the choke air chamber C6, the pressurizing air chamber C8, and the pump air chamber C13.

[0120] The pressure variable unit 81 has one or more pump units. In one example, the pressure variable unit 81 has a first pump unit 82 and a second pump unit 83. The first pump unit 82 and the second pump unit 83 are each connected to a plurality of connection targets. The connection targets of the first pump unit 82 and the connection targets of the second pump unit 83 are common. That is, the first pump unit 82 and the second pump unit 83 are connected to the on-off valve 52, the pressurizing portion 53, and the flow path pump 71. The first pump unit 82 and the second pump unit 83 change the pressure of the connection targets by sucking air from the connection targets or discharging air to the connection targets. If the pressure variable unit 81 has a plurality of pump units, it is easy to change the pressure of the connection targets.

[0121] The first pump unit 82 is mounted on the frame 32. The first pump unit 82 is fixed to the frame 32. The second pump unit 83 is mounted on the assembly portion 18. The second pump unit 83 is fixed to the assembly portion 18. The second pump unit 83 is located behind the assembly portion 18. The first pump unit 82 is located at a position higher than the second pump unit 83.

[0122] As Figure 14 and Figure 15 shown, the first pump unit 82 has a mounting member 84. The mounting member 84 is a member mounted on the frame 32. The mounting member 84 is fixed to the frame 32.

[0123] The mounting member 84 has a mounting plate 85. The mounting plate 85 faces the support plate 33. The mounting plate 85 extends along the support plate 33. The mounting plate 85 extends in a direction perpendicular to the scanning direction D1.

[0124] The mounting member 84 has one or more contact portions 86. In one example, the mounting member 84 has two contact portions 86. The contact portions 86 extend from the mounting plate 85. The contact portions 86 are portions that contact the support portions 34.

[0125] The contact portion 86 has a first contact piece 87 and a second contact piece 88. The first contact piece 87 extends from the mounting plate 85. The first contact piece 87 extends toward the support plate 33. The first contact piece 87 extends perpendicularly to the mounting plate 85. The second contact piece 88 extends from the first contact piece 87. The second contact piece 88 extends from the front end of the first contact piece 87. The second contact piece 88 extends perpendicularly from the first contact piece 87. The two second contact pieces 88 extend in a separated manner from each other.

[0126] The contact portion 86 is mounted on the support portion 34. Specifically, the contact portion 86 is mounted on the support portion 34 by hooking the second contact piece 88 on the support portion 34. For example, the support portion 34 is inserted into the contact portion 86 from below, so that the contact portion 86 is hooked on the support portion 34. At this time, the second contact piece 88 is located between the support plate 33 and the second support piece 36. Thus, the first pump unit 82 is supported by the frame 32.

[0127] The mounting member 84 has an insertion portion 89. The insertion portion 89 extends from the mounting plate 85. The insertion portion 89 extends toward the support plate 33. The insertion portion 89 extends perpendicularly to the mounting plate 85. The insertion portion 89 is a portion into which the fixing member 41 is inserted. The insertion portion 89 is, for example, located at a position above the contact portion 86.

[0128] One or more insertion grooves 90 are formed in the insertion portion 89. In one example, two insertion grooves 90 are formed in the insertion portion 89. The mounting portion 37 is inserted into the insertion groove 90. Specifically, the second mounting piece 39 is inserted into the insertion groove 90. The second mounting piece 39 is inserted into the insertion groove 90 from below. The insertion portion 89 is mounted on the mounting portion 37 by inserting the mounting portion 37 into the insertion groove 90.

[0129] By mounting the contact portion 86 and the insertion portion 89 on the frame 32, the posture of the first pump unit 82 is stabilized. Since the first pump unit 82 is supported at two points, namely the contact portion 86 and the insertion portion 89, the sway of the first pump unit 82 can be reduced.

[0130] As Figure 16 and Figure 17 shown, by lifting the first pump unit 82 upward, the contact portion 86 is removed from the support portion 34. By lifting the first pump unit 82 upward, the insertion portion 89 is removed from the mounting portion 37. Thus, the first pump unit 82 is removed from the frame 32. When the first pump unit 82 is mounted on the frame 32, the support portion 34 is inserted into the contact portion 86, and the mounting portion 37 is inserted into the insertion portion 89. In this way, the first pump unit 82 is configured to be easily disassembled and assembled from above. Thus, the maintainability of the pressure variable unit 81 is improved.

[0131] As Figure 18 shown, the first pump unit 82 has a base member 91. Various components of the first pump unit 82 are mounted on the base member 91. The mounting member 84 is mounted on the base member 91.

[0132] As Figure 18 and Figure 19 shown, the first pump unit 82 has a motor. Specifically, the first pump unit 82 has a first motor 92. The first motor 92 is configured to rotate forward and backward. In one example, the first motor 92 is configured to be able to extract power from a double shaft.

[0133] The first pump unit 82 has a pump. Specifically, the first pump unit 82 has a first pump 93. The first pump 93 changes the pressure in the accommodating portion 28. In one example, the first pump 93 is a vacuum pump. The first pump 93 may also be a pressure pump.

[0134] The first pump 93 is connected to the first motor 92. The first pump 93 is driven by the power of the first motor 92. The first pump 93 is driven together with the driving of the first motor 92. In one example, whether the first motor 92 rotates forward or reverses, the first pump 93 is driven to generate a negative pressure.

[0135] The first pump 93 is connected to a plurality of connection objects of the pressure variable unit 81. In one example, the first pump 93 is connected to a plurality of accommodating portions 28. Specifically, the first pump 93 is connected to the on-off valve 52, the pressurizing portion 53, and the flow path pump 71.

[0136] The first pump unit 82 has a switching portion 94. The switching portion 94 is configured to switch the connection between the first pump 93 and a plurality of connection objects of the first pump unit 82. The switching portion 94 switches this connection so as to change the pressure of any one of the plurality of connection objects. It can also be said that the switching portion 94 switches the path connecting the connection object and the first pump 93. In one example, the switching portion 94 switches the connection between the plurality of accommodating portions 28 and the first pump 93.

[0137] The switching portion 94 is connected to the first motor 92. The switching portion 94 uses the power of the first motor 92 to switch the connection between the first pump 93 and a plurality of connection objects of the first pump unit 82. That is, the switching portion 94 uses the power of the first motor 92 to switch the path connecting the accommodating portion 28 and the first pump 93. The switching portion 94 causes the negative pressure generated by the first pump 93 to act on any one of the accommodating portions 28.

[0138] The switching portion 94 has a flow path member 95. The flow path member 95 is connected to the first pump 93. Air flows in the flow path member 95. The negative pressure generated by the first pump 93 acts on the accommodating portion 28 through the flow path member 95.

[0139] The flow path component 95 has a flow path substrate 96 and a cover component 97. The flow path substrate 96 is bonded to the cover component 97. For example, the flow path substrate 96 and the cover component 97 are laser cladded. The flow path substrate 96 and the cover component 97 can be hot-fused or bonded with an adhesive.

[0140] As Figure 20 As shown, a plurality of switching channels are defined in the flow path component 95. In one example, a pump channel P1, an open channel P2, a pressurizing channel P3, a blocking channel P4, and a conducting channel P5 are defined in the flow path component 95. The pump channel P1 is a flow path communicating with the first pump 93. The pump channel P1 is a flow path communicating with the flow path pump 71. The open channel P2 is a flow path communicating with the atmosphere. The pressurizing channel P3 is a flow path communicating with the pressurizing unit 53. The blocking channel P4 is a flow path communicating with the on-off valve 52. The conducting channel P5 is a flow path communicating with each of the pump channel P1, the open channel P2, the pressurizing channel P3, and the blocking channel P4.

[0141] A plurality of switching ports are opened in the flow path component 95. The switching port is an opening that allows the switching channels to communicate with each other. In one example, a pump port 98, an open port 99, a pressurizing port 100, and a blocking port 101 are opened in the flow path substrate 96. The pump port 98 allows the pump channel P1 to communicate with the conducting channel P5. The open port 99 allows the open channel P2 to communicate with the conducting channel P5. The pressurizing port 100 allows the pressurizing channel P3 to communicate with the conducting channel P5. The blocking port 101 allows the blocking channel P4 to communicate with the conducting channel P5.

[0142] The first pump 93 is opened to the atmosphere through the pump port 98 and the open port 99. The first pump 93 communicates with the pressurizing unit 53 through the pump port 98 and the pressurizing port 100. The first pump 93 communicates with the on-off valve 52 through the pump port 98 and the blocking port 101.

[0143] The flow path component 95 has a plurality of conducting tubes. The conducting tube is a tube through which air enters and exits the flow path component 95. In one example, the flow path component 95 has a pump tube 102, a flow path pump tube 103, an open tube 104, a pressurizing tube 105, and a blocking tube 106. The pump tube 102 communicates with the pump channel P1. The pump tube 102 is connected to the first pump 93. The pump tube 102 is connected to the first pump 93 via a tube, for example. The flow path pump tube 103 communicates with the pump channel P1. The flow path pump tube 103 is connected to the flow path pump 71 via a tube, for example. The open tube 104 communicates with the open channel P2. The open tube 104 is opened to the atmosphere. The pressurizing tube 105 communicates with the pressurizing channel P3. The pressurizing tube 105 is connected to the pressurizing unit 53 via a tube, for example. The blocking tube 106 communicates with the blocking channel P4. The blocking tube 106 is connected to the on-off valve 52 via a tube, for example.

[0144] As Figure 19As shown, the switching unit 94 has a selection valve 107. The selection valve 107 is configured to open and close a plurality of switching channels. The selection valve 107 opens any one of the plurality of switching channels. In one example, the selection valve 107 opens any one of the pump channel P1, the open channel P2, the pressurization channel P3, and the choke channel P4. Thereby, the selection valve 107 communicates the first pump 93 with any one of the accommodating portions 28.

[0145] The selection valve 107 has a valve seat 108. The valve seat 108 is mounted on the flow path member 95. Specifically, the valve seat 108 is mounted on the flow path substrate 96.

[0146] The selection valve 107 has a plurality of valves. In one example, the selection valve 107 has a pump valve 109, an open valve 110, a pressurization valve 111, and a choke valve 112. The plurality of valves are mounted on the valve seat 108. The pump valve 109, the open valve 110, the pressurization valve 111, and the choke valve 112 are mounted on the valve seat 108.

[0147] The plurality of valves are respectively located between a plurality of connection objects and the first pump 93. Specifically, the plurality of valves are located on the path connecting the connection objects and the first pump 93. The plurality of valves open and close this path. In one example, the plurality of valves open and close the switching ports.

[0148] As Figure 20 shown, the pump valve 109 is located at a position blocking the pump port 98. The pump valve 109 opens and closes the pump port 98. The open valve 110 is located at a position blocking the open port 99. The open valve 110 opens and closes the open port 99. The pressurization valve 111 is located at a position blocking the pressurization port 100. The pressurization valve 111 opens and closes the pressurization port 100. The choke valve 112 is located at a position blocking the choke port 101. The choke valve 112 opens and closes the choke port 101.

[0149] As Figure 19 shown, the selection valve 107 has a plurality of valve stems. In one example, the selection valve 107 has a pump valve stem 113, an open valve stem 114, a pressurization valve stem 115, and a choke valve stem 116. The valve stem is a rod that opens the valve. The valve stem is connected to the valve. The valve stem is mounted on the valve seat 108.

[0150] The pump valve stem 113 is connected to the pump valve 109. The pump valve stem 113 lifts the pump valve 109. Thereby, the pump valve 109 opens. That is, the pump port 98 is opened.

[0151] The open valve stem 114 is connected to the open valve 110. The open valve stem 114 lifts the open valve 110. Thereby, the open valve 110 opens. That is, the open port 99 is opened.

[0152] The pressurization valve stem 115 is connected to the pressurization valve 111. The pressurization valve stem 115 lifts the pressurization valve 111. Thereby, the pressurization valve 111 opens. That is, the pressurization port 100 is opened.

[0153] The choke valve stem 116 is connected to the choke valve 112. The choke valve stem 116 lifts the choke valve 112. Thereby, the choke valve 112 opens. That is, the choke port 101 is opened.

[0154] The switching unit 94 has a cam unit 117. The cam unit 117 is a unit that actuates the valve stem. The cam unit 117 arbitrarily actuates the pump valve stem 113, the open valve stem 114, the pressure valve stem 115, and the choke valve stem 116. That is, the cam unit 117 arbitrarily opens the pump valve 109, the open valve 110, the pressure valve 111, and the choke valve 112.

[0155] The cam unit 117 has a plurality of cams. In one example, the cam unit 117 has a pump cam 118, an open cam 119, a pressure cam 120, and a choke cam 121. The plurality of cams respectively open and close the plurality of valves. The pump cam 118 opens and closes the pump valve 109. The open cam 119 opens and closes the open valve 110. The pressure cam 120 opens and closes the pressure valve 111. The choke cam 121 opens and closes the choke valve 122.

[0156] The cam contacts the valve stem. The cam presses down on the valve stem by rotating. Thereby, the valve is opened. When the cam does not press down on the valve stem, the valve stem does not lift the valve. When the valve stem does not lift the valve, the valve blocks the switching port due to the action of its own weight, spring, etc.

[0157] The pump cam 118 contacts the pump valve stem 113. The pump cam 118 presses down on the pump valve stem 113 by rotating. Thereby, the pump valve 109 opens the pump port 98.

[0158] The open cam 119 contacts the open valve stem 114. The open cam 119 presses down on the open valve stem 114 by rotating. Thereby, the open valve 110 opens the open port 99.

[0159] The pressure cam 120 contacts the pressure valve stem 115. The pressure cam 120 presses down on the pressure valve stem 115 by rotating. Thereby, the pressure valve 111 opens the pressure port 100.

[0160] The choke cam 121 contacts the choke valve stem 116. The choke cam 121 presses down on the choke valve stem 116 by rotating. Thereby, the choke valve 112 opens the choke port 101.

[0161] The cam unit 117 has a camshaft 122. The camshaft 122 is the rotation axis of the cams. Specifically, the camshaft 122 is the rotation axis of the pump cam 118, the opening cam 119, the pressurizing cam 120, and the flow blocking cam 121. As the camshaft 122 rotates, the pump cam 118, the opening cam 119, the pressurizing cam 120, and the flow blocking cam 121 rotate. Therefore, the rotation angle of the camshaft 122 corresponds to the opening and closing of the pump valve 109, the opening and closing of the opening valve 110, the opening and closing of the pressurizing valve 111, and the opening and closing of the flow blocking valve 112.

[0162] The first pump unit 82 has a transmission part. Specifically, the first pump unit 82 has a first transmission part 123. The first transmission part 123 is located between the first motor 92 and the switching part 94. Specifically, the first transmission part 123 is located between the first motor 92 and the switching part 94 in the path of transmitting the power of the first motor 92.

[0163] The first transmission part 123 is configured to transmit the power of the first motor 92 to the switching part 94. Specifically, the first transmission part 123 transmits the power of the first motor 92 to the camshaft 122. The first transmission part 123 rotates the camshaft 122 by using the power of the first motor 92. Thereby, the plurality of cams rotate.

[0164] The first transmission part 123 is configured to transmit the power of the first motor 92 to the switching part 94 when the first motor 92 rotates in the reverse direction. That is, when the first motor 92 rotates in the reverse direction, the first transmission part 123 rotates the camshaft 122 by using the power of the first motor 92.

[0165] The first transmission part 123 is configured not to transmit the power of the first motor 92 to the switching part 94 when the first motor 92 rotates in the forward direction. That is, when the first motor 92 rotates in the forward direction, the first transmission part 123 does not rotate the camshaft 122.

[0166] The first transmission part 123 rotates the camshaft 122 only in one direction. Through the first transmission part 123, the cams rotate when the first motor 92 rotates in the reverse direction, and the cams do not rotate when the first motor 92 rotates in the forward direction. Thus, in the first pump unit 82, the first pump 93 can be driven by the first motor 92, and the switching part 94 can be driven.

[0167] The first transmission part 123 has an output pinion 124. The output pinion 124 is mounted on the first motor 92. Specifically, the output pinion 124 is mounted on the shaft of the first motor 92.

[0168] The first transmission unit 123 has an output belt 125. The output belt 125 is wound around the output pinion 124. The output belt 125 rotates together with the output pinion 124. The output belt 125 transmits the torque of the output pinion 124.

[0169] The first transmission unit 123 has a plurality of gears. In one example, the first transmission unit 123 has an output gear 126, a transmission gear 127, a connecting gear 128, a relay gear 129, and a cam gear 130.

[0170] The output gear 126 is connected to the output pinion 124. Specifically, the output belt 125 is wound around the output gear 126. The output gear 126 is connected to the output pinion 124 via the output belt 125. The output gear 126 rotates together with the output pinion 124. The output gear 126 may also be located at a position where it directly meshes with the output pinion 124.

[0171] The transmission gear 127 is connected to the output gear 126. The transmission gear 127 rotates together with the output gear 126. The transmission gear 127 is supported by a transmission shaft 131 described later.

[0172] The connecting gear 128 is connected to the transmission gear 127. The connecting gear 128 is supported by the transmission shaft 131. That is, the connecting gear 128 and the transmission gear 127 are located on the same axis. The connecting gear 128 rotates together with the transmission shaft 131.

[0173] The relay gear 129 is connected to the connecting gear 128. The relay gear 129 meshes with the connecting gear 128. The relay gear 129 rotates together with the connecting gear 128.

[0174] The cam gear 130 is connected to the relay gear 129. The cam gear 130 meshes with the relay gear 129. The cam gear 130 rotates together with the relay gear 129.

[0175] The first transmission unit 123 has a transmission shaft 131. The transmission shaft 131 transmits the torque of the transmission gear 127 to the connecting gear 128. The transmission shaft 131 rotates as the transmission gear 127 rotates. Specifically, when the first motor 92 rotates in the reverse direction, the transmission shaft 131 rotates together with the transmission gear 127. When the first motor 92 rotates in the forward direction, the transmission shaft 131 does not rotate.

[0176] As Figure 21 and Figure 22As shown, the transmission shaft 131 has a transmission support portion 132 and a connection support portion 133. The transmission support portion 132 is the portion that supports the transmission gear 127. The transmission support portion 132 is inserted into the transmission gear 127. The connection support portion 133 is the portion that supports the connection gear 128. The connection support portion 133 is inserted into the connection gear 128. In one example, the connection support portion 133 has a smaller diameter than the transmission support portion 132.

[0177] When viewed axially of the transmission shaft 131, the connection support portion 133 has a D-shaped configuration. The shaft hole of the connection gear 128 has a corresponding shape. Thus, the connection gear 128 rotates integrally with the transmission shaft 131.

[0178] As Figure 22 shown, the first transmission portion 123 has a one-way clutch 134. The one-way clutch 134 is configured to transmit power when the first motor 92 rotates in the reverse direction. For example, the one-way clutch 134 is mounted on the transmission gear 127. The one-way clutch 134 and the transmission gear 127 are supported together on the transmission shaft 131. When the first motor 92 rotates in the reverse direction, the one-way clutch 134 transmits power from the transmission gear 127 to the transmission shaft 131. For example, when the first motor 92 rotates in the reverse direction, the one-way clutch 134 rotates together with the transmission gear 127. The transmission shaft 131 rotates as the one-way clutch 134 rotates.

[0179] When the first motor 92 rotates in the forward direction, the one-way clutch 134 does not transmit power from the transmission gear 127 to the transmission shaft 131. For example, when the first motor 92 rotates in the forward direction, the one-way clutch 134 does not rotate relative to the transmission gear 127. That is, the one-way clutch 134 remains stationary when the first motor 92 rotates in the forward direction. Therefore, when the first motor 92 rotates in the forward direction, power is not transmitted to the switching portion 94.

[0180] When the transmission gear 127 rotates in the direction corresponding to the reverse rotation of the first motor 92, the one-way clutch 134 rotates together with the transmission gear 127. The one-way clutch 134 is not limited to being mounted on the transmission gear 127 and may be mounted on other gears.

[0181] As Figure 19 shown, the first pump unit 82 has a detection portion 135. The detection portion 135 is configured to detect the rotation angle of the first motor 92. In one example, the detection portion 135 detects the rotation angle of the camshaft 122. The detection portion 135 detects the rotation angle of the first motor 92 based on the rotation angle of the camshaft 122. Through the detection portion 135, the phase of the cam is controlled with high precision.

[0182] The detection unit 135 has a photoelectric sensor unit 136. The photoelectric sensor unit 136 detects the rotation angle of the first motor 92. In one example, the photoelectric sensor unit 136 detects the rotation angle of the camshaft 122. Specifically, the photoelectric sensor unit 136 detects the reference angle of the camshaft 122.

[0183] The photoelectric sensor unit 136 has a light interrupter 137 and a shielding plate 138. The light interrupter 137 is installed on the valve seat 108. The light interrupter 137 detects the shielding plate 138. The shielding plate 138 is installed on the camshaft 122. The shielding plate 138 rotates together with the camshaft 122. The shielding plate 138 passes through the light interrupter 137 during rotation. At this time, the shielding plate 138 is detected by the light interrupter 137. By detecting the shielding plate 138 by the light interrupter 137, the rotation angle of the camshaft 122 is detected. Specifically, the reference angle of the camshaft 122 is detected.

[0184] The detection unit 135 has a rotary encoder 139. The rotary encoder 139 detects the rotation angle of the first motor 92. In one example, the rotary encoder 139 detects the rotation angle of the camshaft 122. Specifically, the rotary encoder 139 detects the rotation amount of the camshaft 122.

[0185] The rotary encoder 139 has an encoder 140 and a scale 141. The encoder 140 is installed on the valve seat 108. The encoder 140 reads the scale 141. The scale 141 is installed on the camshaft 122. The scale 141 rotates together with the camshaft 122. At this time, the scale 141 is read by the encoder 140. Thus, the rotary encoder 139 detects the rotation amount of the camshaft 122.

[0186] The detection unit 135 detects the rotation amount of the camshaft 122 starting from the reference angle. Thus, the detection unit 135 detects the rotation angle of the camshaft 122. Through the detection unit 135, when the first motor 92 rotates in the reverse direction, the rotation angle of the first motor 92 is controlled with high precision. In one example, when the camshaft 122 is at the reference angle, the pump cam 118 closes the pump valve 109, the opening cam 119 opens the opening valve 110, the pressurizing cam 120 opens the pressurizing valve 111, and the flow blocking cam 121 opens the flow blocking valve 112. When the camshaft 122 starts to rotate from the reference angle, the phases of the multiple cams change respectively.

[0187] The detection unit 135 may also be composed only of the photoelectric sensor unit 136. In this case, it is preferable that a plurality of slits corresponding to the rotation angle of the camshaft 122 are formed in the shielding plate 138. Thus, the light interrupter 137 can detect the rotation angle corresponding to the slit.

[0188] The first pump unit 82 is controlled by the control unit 42. Specifically, the first motor 92 is controlled by the control unit 42. When the first motor 92 rotates in the reverse direction, the control unit 42 performs PID control based on the detection result of the detection unit 135. Thereby, the phase of the cam is controlled with high precision. When the first motor 92 rotates in the forward direction, the control unit 42 performs open control. When the first motor 92 rotates in the forward direction, the camshaft 122 does not rotate. Therefore, the detection unit 135 cannot detect the rotation angle. In addition, when the first motor 92 rotates in the forward direction, only the first pump 93 is driven. Therefore, when the first motor 92 rotates in the forward direction, it is not necessary to finely control the rotation angle of the first motor 92.

[0189] As Figure 23 shown, the second pump unit 83 has a motor. Specifically, the second pump unit 83 has a second motor 142. The second motor 142 is configured to rotate forward and backward. In one example, the second motor 142 is configured to be able to extract power from a double shaft in the same manner as the first motor 92.

[0190] The second pump unit 83 has a pump. Specifically, the second pump unit 83 has a second pump 143. The second pump 143 changes the pressure in the accommodation part 28. In one example, the second pump 143 is a vacuum pump. The second pump 143 may also be a pressure pump.

[0191] The second pump 143 is connected to the second motor 142. The second pump 143 is driven by the power of the second motor 142. The second pump 143 is driven in conjunction with the driving of the second motor 142. In one example, whether the second motor 142 rotates forward or backward, the second pump 143 is driven to generate a negative pressure.

[0192] The second pump 143 is configured to change the pressure of at least one of the plurality of connection objects of the pressure variable unit 81. The second pump 143 is connected to at least one of the plurality of connection objects of the pressure variable unit 81. That is, the second pump 143 is connected to at least one of the plurality of connection objects of the first pump 93. In one example, the second pump 143 is connected to all of the plurality of connection objects of the first pump 93. The second pump 143 is connected to the plurality of accommodation parts 28. The second pump 143 is connected to the on-off valve 52, the pressurizing part 53, and the flow path pump 71. Therefore, the pressure variable unit 81 can change the pressure in the accommodation part 28 through the cooperation of the first pump 93 and the second pump 143.

[0193] The second pump unit 83 has an atmosphere opening portion 144. The atmosphere opening portion 144 is connected to a plurality of connection objects of the pressure variable unit 81. The atmosphere opening portion 144 is configured to open the plurality of connection objects to the atmosphere. That is, the atmosphere opening portion 144 opens the accommodation portion 28 to the atmosphere. Specifically, the atmosphere opening portion 144 opens the air chamber C2 to the atmosphere. In one example, the atmosphere opening portion 144 opens the choke air chamber C6, the pressurized air chamber C8, the pump air chamber C13, etc. to the atmosphere.

[0194] The atmosphere opening portion 144 has an atmosphere opening base 145, an atmosphere opening valve 146, and an atmosphere opening rod 147. The atmosphere opening base 145 is configured such that the inside of the atmosphere opening base 145 communicates with the atmosphere. The atmosphere opening valve 146 is installed on the atmosphere opening base 145. The atmosphere opening valve 146 opens and closes the atmosphere opening base 145. When the atmosphere opening valve 146 is opened, the atmosphere opening base 145 is opened to the atmosphere. The atmosphere opening rod 147 is installed on the atmosphere opening base 145. The atmosphere opening rod 147 is connected to the atmosphere opening valve 146. The atmosphere opening rod 147 lifts the atmosphere opening valve 146. Thereby, the atmosphere opening valve 146 is opened.

[0195] The atmosphere opening portion 144 is configured to close when the second motor 142 rotates forward. The atmosphere opening portion 144 is configured to open when the second motor 142 rotates in reverse. Specifically, the atmosphere opening portion 144 is closed when the second motor 142 rotates forward by the power transmitted from the second motor 142, and is opened when the second motor 142 rotates in reverse.

[0196] The second pump unit 83 has a transmission portion. Specifically, the second pump unit 83 has a second transmission portion 148. The second transmission portion 148 is located between the second motor 142 and the atmosphere opening portion 144. Specifically, the second transmission portion 148 is located between the second motor 142 and the atmosphere opening portion 144 in the path of transmitting the power of the second motor 142.

[0197] The second transmission portion 148 is configured to transmit the power of the second motor 142 to the atmosphere opening portion 144. Specifically, the second transmission portion 148 transmits the power of the second motor 142 to the atmosphere opening rod 147. The second transmission portion 148 uses the power of the second motor 142 to actuate the atmosphere opening rod 147. Thereby, the atmosphere opening valve 146 opens and closes.

[0198] The second transmission unit 148 is configured to correspond the rotation direction of the second motor 142 to the opening and closing of the atmosphere open valve 146. When the second motor 142 rotates forward, the second transmission unit 148 closes the atmosphere open valve 146. When the second motor 142 rotates in the reverse direction, the second transmission unit 148 opens the atmosphere open valve 146. In this way, in the second pump unit 83, the second pump 143 can be driven by the second motor 142, and the atmosphere open part 144 can be driven.

[0199] The second transmission unit 148 has a drive pinion 149. The drive pinion 149 is mounted on the second motor 142. Specifically, the drive pinion 149 is mounted on the shaft of the second motor 142.

[0200] The second transmission unit 148 has a drive belt 150. The drive belt 150 is wound around the drive pinion 149. The drive belt 150 rotates together with the drive pinion 149. The drive belt 150 transmits the power of the drive pinion 149.

[0201] The second transmission unit 148 has a plurality of gears. In one example, the second transmission unit 148 has a drive gear 151 and a connecting gear 152.

[0202] The drive gear 151 is connected to the drive pinion 149. Specifically, the drive belt 150 is wound around the drive gear 151. The drive gear 151 is connected to the drive pinion 149 via the drive belt 150. The drive gear 151 rotates together with the drive pinion 149. The drive gear 151 may also be located at a position directly meshing with the drive pinion 149.

[0203] The connecting gear 152 is connected to the drive gear 151. The connecting gear 152 rotates together with the drive gear 151. The connecting gear 152 is supported by a connecting shaft 153 described later.

[0204] The second transmission unit 148 has a connecting shaft 153. The connecting shaft 153 rotates together with the connecting gear 152.

[0205] The second transmission unit 148 has a friction clutch 154. The friction clutch 154 is supported by the connecting shaft 153. The friction clutch 154 is configured to slide relative to the connecting shaft 153 when a torque equal to or greater than a specified value acts thereon.

[0206] The second transmission unit 148 has an atmosphere open cam 155. The atmosphere open cam 155 is mounted on the friction clutch 154. The atmosphere open cam 155 rotates together with the friction clutch 154.

[0207] The atmosphere open cam 155 contacts the atmosphere open lever 147. The atmosphere open cam 155 presses down the atmosphere open lever 147. Thereby, the atmosphere open valve 146 is opened.

[0208] When the second motor 142 rotates forward, the atmosphere opening cam 155 actuates the atmosphere opening lever 147 to close the atmosphere opening portion 144. That is, when the second motor 142 rotates forward, the atmosphere opening cam 155 does not press down the atmosphere opening lever 147. When the atmosphere opening cam 155 does not press down the atmosphere opening lever 147, the atmosphere opening valve 146 blocks the atmosphere opening base 145 due to its own weight, the spring, and other effects. When the second motor 142 rotates in the reverse direction, the atmosphere opening cam 155 actuates the atmosphere opening lever 147 to open the atmosphere opening portion 144. That is, when the second motor 142 rotates in the reverse direction, the atmosphere opening cam 155 presses down the atmosphere opening lever 147.

[0209] The phase of the atmosphere opening cam 155 is restricted within a specified range by the friction clutch 154. Therefore, when the second motor 142 rotates forward, the phase of the atmosphere opening cam 155 is maintained in a state where it does not press down the atmosphere opening lever 147. When the second motor 142 rotates in the reverse direction, the phase of the atmosphere opening cam 155 is maintained in a state where it presses down the atmosphere opening lever 147. For example, the phase of the atmosphere opening cam 155 is restricted by contacting a restricting member (not shown). At this time, the friction clutch 154 slides relative to the connecting shaft 153.

[0210] As Figure 24 shown, the first pump unit 82 and the second pump unit 83 are connected to each other. The second pump unit 83 is connected between the first pump unit 82 and the flow path pump 71. Specifically, the second pump 143 is connected between the first pump 93 and the flow path pump 71. That is, the second pump 143 is connected to the flow path pump pipe 103. The second pump 143 is connected to the pump air pipe 75. The first pump 93 and the second pump 143 are always in communication with the flow path pump 71. By opening the selection valve 107, the first pump 93 and the second pump 143 are in communication with the flow portion 27. The specific operation of the pressure variable unit 81 will be described later.

[0211] As Figure 4 、 Figure 5 、 Figure 6 And Figure 7As shown, the liquid supply unit 30 has a supply flow path 161. The supply flow path 161 is a flow path through which liquid flows. Specifically, the supply flow path 161 is a flow path through which liquid flows toward the liquid ejection unit 22. Liquid is supplied to the ejection portion 23 through the supply flow path 161. The supply flow path 161 is connected to the liquid container 20 and the liquid ejection unit 22. Specifically, the supply flow path 161 is connected to the liquid container 20 and the flow portion 27. In one example, the supply flow path 161 is connected to the fitting portion 18 and the ejection joint 54. The supply flow path 161 is connected to the accommodation portion 28 such as the on-off valve 52 and the pressurizing portion 53 through the ejection joint 54. The supply flow path 161 communicates with the liquid chamber C1.

[0212] The liquid supply unit 30 has an air flow path 162. The air flow path 162 is a flow path through which air flows. The air flow path 162 is connected to the pressure variable unit 81. Specifically, the air flow path 162 is connected to the pump unit. More specifically, the air flow path 162 is connected to the pump. In one example, the air flow path 162 is connected to the first pump 93 and the second pump 143.

[0213] The air flow path 162 is connected to a plurality of connection objects of the pressure variable unit 81. The pressure variable unit 81 is connected to the plurality of connection objects through the air flow path 162. The air flow path 162 is connected to the accommodation portion 28. In one example, the air flow path 162 is connected to a plurality of accommodation portions 28. The air flow path 162 is connected to the on-off valve 52, the pressurizing portion 53, and the flow path pump 71. The negative pressure generated by the pump unit acts on the on-off valve 52, the pressurizing portion 53, and the flow path pump 71 through the air flow path 162. The air flow path 162 communicates with the air chamber C2.

[0214] The supply flow path 161 and the air flow path 162 each have a fixed portion and a movable portion. The supply flow path 161 has a first fixed portion 163 and a first movable portion 164. The air flow path 162 has a second fixed portion 165 and a second movable portion 166. The fixed portion is the portion fixed to the housing 12. The movable portion is the portion that deforms as the liquid ejection unit 22 moves in the scanning direction D1.

[0215] The first fixed portion 163 is connected to the fitting portion 18 and a relay joint 168 described later. Since the positional relationship between the fitting portion 18 and the relay joint 168 does not change, the first fixed portion 163 does not deform.

[0216] The first movable portion 164 is connected to the relay joint 168 and the liquid ejection unit 22. Specifically, the first movable portion 164 is connected to the relay joint 168 and the flow portion 27. The first movable portion 164 is connected to the relay joint 168 and the ejection joint 54. As the liquid ejection unit 22 moves, the positional relationship between the relay joint 168 and the ejection joint 54 changes. Therefore, the first movable portion 164 deforms.

[0217] The second fixed part 165 is connected to the flow path pump 71 and the pump unit. Specifically, the second fixed part 165 is connected to the flow path pump 71, the first pump unit 82, and the second pump unit 83. The second fixed part 165 extends from the flow path pump 71 toward the first pump unit 82. The second fixed part 165 is connected to the second pump unit 83 midway through its extension from the flow path pump 71 toward the first pump unit 82. Since the positional relationship among the flow path pump 71, the first pump unit 82, and the second pump unit 83 remains unchanged, the second fixed part 165 does not deform.

[0218] The second movable part 166 is connected to the relay joint 168 and the liquid ejection unit 22. Specifically, the second movable part 166 is connected to the relay joint 168 and the flow part 27. The second movable part 166 is connected to the relay joint 168 and the ejection joint 54. Similarly to the first movable part 164, the second movable part 166 deforms by moving through the liquid ejection unit 22.

[0219] The liquid supply unit 30 has a guide member 167. The guide member 167 is configured to guide the supply flow path 161 and the air flow path 162. The guide member 167 is fixed to the housing 12. The guide member 167 guides the fixed part. The guide member 167 guides the first fixed part 163 from the flow path pump 71 to the relay joint 168. The guide member 167 guides the second fixed part 165 from the flow path pump 71 to the first pump unit 82. The guide member 167 guides the second fixed part 165 from the second pump unit 83 to the first pump unit 82.

[0220] The liquid supply unit 30 has a relay joint 168. The relay joint 168 is configured to relay the supply flow path 161 and the air flow path 162. The relay joint 168 is located midway through the supply flow path 161. The relay joint 168 is located midway through the air flow path 162. The relay joint 168 is mounted on the frame 32, for example.

[0221] The relay joint 168 is connected to the first pump unit 82. Specifically, the relay joint 168 is connected to the pressure pipe 105 and the choke pipe 106. The relay joint 168 is connected to the pressure pipe 105 and the choke pipe 106 via a pipe, for example.

[0222] As Figure 25 and Figure 26As shown, the liquid supply unit 30 has a plurality of flexible members. Specifically, the supply flow path 161 and the air flow path 162 each have a flexible member. Specifically, the supply flow path 161 has a first flexible member 169. The air flow path 162 has a second flexible member 170. A flexible member is a member having flexibility. A flexible member is a tube. The first flexible member 169 is a liquid tube. In one example, the first flexible member 169 is a multi-connected tube. The second flexible member 170 is an air tube.

[0223] The flexible members constitute the movable parts. The first flexible member 169 constitutes the first movable part 164. The second flexible member 170 constitutes the second movable part 166. Therefore, the first flexible member 169 and the second flexible member 170 are deformed as the liquid ejection unit 22 moves. The fixed part can be constituted by a flexible member in the same manner as the movable part, or can be constituted by a rigid member having rigidity. The rigid member is, for example, a pipe. In one example, the first fixed part 163 and the second fixed part 165 are each constituted by a flexible member.

[0224] The first flexible member 169 and the second flexible member 170 extend in a side-by-side manner. The first flexible member 169 and the second flexible member 170 extend from the relay joint 168 toward the liquid ejection unit 22. The first flexible member 169 and the second flexible member 170 extend while bending. By arranging the first flexible member 169 and the second flexible member 170 side by side, an increase in the arrangement space of the first flexible member 169 and the second flexible member 170 is suppressed.

[0225] The first flexible member 169 and the second flexible member 170 each have an extended portion and a bent portion. The first flexible member 169 has a first extended portion 171 and a first bent portion 172. The second flexible member 170 has a second extended portion 173 and a second bent portion 174. The extended portion is a portion extending in the scanning direction D1. Specifically, the extended portion is a portion extending linearly from the relay joint 168. The bent portion is a portion bent in an arc shape from the extended portion toward the liquid ejection unit 22. As the liquid ejection unit 22 moves, the lengths of the extended portion and the bent portion change. In one example, the farther the liquid ejection unit 22 moves in the scanning direction D1, the shorter the extended portion becomes, and the longer the bent portion becomes.

[0226] The elasticity of the first flexible member 169 is greater than that of the second flexible member 170. This is because higher barrier properties are required for the first flexible member 169 than for the second flexible member 170. In the first flexible member 169, a tube with a thick wall is used to suppress air from entering the liquid. Therefore, the first flexible member 169 is sometimes more difficult to deform than the second flexible member 170.

[0227] The first flexible member 169 extends while being aligned with a curvature smaller than that of the second flexible member 170. That is, the first flexible member 169 bends in such a way as to pass through a position more outside than the second flexible member 170. As a result, the curvature of the first flexible member 169 is smaller than the curvature of the second flexible member 170. By reducing the curvature of the first flexible member 169, the reaction force acting on the liquid ejection unit 22 is reduced.

[0228] As Figure 26 shown, the upstream ends of the first flexible member 169 and the second flexible member 170 are located on one side with respect to the center of the movement area A1. Specifically, the upstream ends of the first flexible member 169 and the second flexible member 170 are located at a position more on one side than the center line L1 in the scanning direction D1. The center line L1 is a virtual line that bisects the movement area A1 in the scanning direction D1. That is, the upstream ends of the first flexible member 169 and the second flexible member 170 are centrally located in the scanning direction D1. This is because the relay joint 168 is located at a position more on one side than the center line L1. Since the upstream ends of the first flexible member 169 and the second flexible member 170 are centrally located, it is easy to remove the first flexible member 169 and the second flexible member 170.

[0229] By arranging the upstream ends of the first flexible member 169 and the second flexible member 170 in a concentrated manner, the possibility that the length of the first flexible member 169 deviates significantly from the length of the second flexible member 170 is reduced. By making the length of the first flexible member 169 close to the length of the second flexible member 170, it is easy to align the first flexible member 169 with the second flexible member 170. As a result, the space occupied by the first flexible member 169 and the second flexible member 170 can be reduced.

[0230] In the first flexible member 169 and the second flexible member 170, since they are deformed as the liquid ejection unit 22 moves, there is a possibility of rubbing against other components. In this case, the first flexible member 169 and the second flexible member 170 may be worn.

[0231] As Figure 25 and Figure 26As shown, the liquid supply unit 30 has one or more bundling bodies 175. In one example, the liquid supply unit 30 has two bundling bodies 175. The bundling body 175 is a component that bundles the supply flow path 161 and the air flow path 162. The bundling body 175 bundles the first movable part 164 and the second movable part 166. The bundling body 175 bundles the first flexible member 169 and the second flexible member 170. The bundling body 175 bundles the first flexible member 169 and the second flexible member 170 in such a way that they do not contact each other. Thereby, the possibility of the first flexible member 169 and the second flexible member 170 rubbing against each other is reduced.

[0232] As Figure 27 and Figure 28 shown, the bundling body 175 has a holding portion 176. The holding portion 176 holds the first flexible member 169. The holding portion 176 holds the first flexible member 169 by clamping the first flexible member 169. Therefore, even if the first flexible member 169 is deformed, the holding portion 176 and the first flexible member 169 do not rub against each other. Therefore, the possibility of wear of the first flexible member 169 is reduced. The holding portion 176 is, for example, a clamp.

[0233] The bundling body 175 has a support portion 177. The support portion 177 extends from the holding portion 176. The support portion 177 extends in a manner approaching the liquid ejection unit 22 from the holding portion 176. Figure 27 and Figure 28 shown, the support portion 177 extends downward.

[0234] The support portion 177 supports the second flexible member 170. The support portion 177 supports the second flexible member 170 in such a way as to space apart the first flexible member 169 and the second flexible member 170. The support portion 177 supports the second flexible member 170 in such a way that the second flexible member 170 follows the first flexible member 169. The support portion 177 supports the second flexible member 170, for example, in such a way that the second flexible member 170 is suspended from the first flexible member 169.

[0235] The support portion 177 has an arm 178. The arm 178 extends from the holding portion 176. The arm 178 extends in a manner approaching the liquid ejection unit 22 from the holding portion 176.

[0236] The support portion 177 has a pulley 179. The pulley 179 is mounted on the arm 178. The pulley 179 can rotate relative to the arm 178. The pulley 179 contacts the second flexible member 170. The pulley 179 supports the second flexible member 170.

[0237] The pulley 179 has flanges 180 at both axial ends thereof. Through the flanges 180, the pulley 179 is configured such that the diameters at both axial ends are larger than the diameter at the center. Thereby, the possibility of the second flexible member 170 coming off from the pulley 179 is reduced. The possibility of the second flexible member 170 coming into contact with the arm 178 is reduced. Thereby, the possibility of wear of the second flexible member 170 is reduced.

[0238] The flange 180 may also have an inclined surface 181. The inclined surface 181 is inclined such that the diameter of the flange 180 becomes smaller toward the center in the axial direction. Thereby, the second flexible member 170 easily converges to the center of the pulley 179.

[0239] As Figure 29 , Figure 30 and Figure 31 shown, the bundling body 175 may hold the first extension portion 171 or the first bent portion 172 with respect to the first flexible member 169. The bundling body 175 holds the first extension portion 171 or holds the first bent portion 172 according to the position of the liquid ejection unit 22. In one example, when the liquid ejection unit 22 is in the standby position, the two bundling bodies 175 hold the first extension portion 171. When the liquid ejection unit 22 is in the return position, the two bundling bodies 175 hold the first bent portion 172. When the liquid ejection unit 22 is between the standby position and the return position, one of the two bundling bodies 175 holds the first extension portion 171 and the other holds the first bent portion 172.

[0240] The bundling body 175 may support the second extension portion 173 or the second bent portion 174 with respect to the second flexible member 170. The bundling body 175 supports the second extension portion 173 or supports the second bent portion 174 according to the position of the liquid ejection unit 22. In one example, when the liquid ejection unit 22 is in the standby position, the two bundling bodies 175 support the second extension portion 173. When the liquid ejection unit 22 is in the return position, the two bundling bodies 175 hold the second bent portion 174. When the liquid ejection unit 22 is between the standby position and the return position, one of the two bundling bodies 175 holds the second extension portion 173 and the other holds the second bent portion 174.

[0241] In the bundling body 175 where the holding portion 176 holds the first extension portion 171, the support portion 177 supports the second flexible member 170 at a position closer to the liquid ejection unit 22 than the holding portion 176. This is because the support portion 177 extends in a manner approaching the liquid ejection unit 22 from the holding portion 176. For example, the support portion 177 supports the second flexible member 170 at a position lower than the holding portion 176. In one example, when the liquid ejection unit 22 is in the standby position, the two bundling bodies 175 are located such that the holding portion 176 holds the first extension portion 171 and the support portion 177 supports the second flexible member 170 at a position lower than the holding portion 176. When the liquid ejection unit 22 is between the standby position and the return position, one bundling body 175 is located such that the holding portion 176 holds the first extension portion 171 and the support portion 177 supports the second flexible member 170 at a position lower than the holding portion 176.

[0242] When the second flexible member 170 deforms as the liquid ejection unit 22 moves, the positional relationship between the pulley 179 and the second flexible member 170 changes. At this time, the pulley 179 rotates due to friction with the second flexible member 170. Therefore, the possibility of the pulley 179 rubbing against the second flexible member 170 is reduced. Therefore, the possibility of wear of the second flexible member 170 is reduced.

[0243] Operation of the pressure variable unit

[0244] Next, the operation of the pressure variable unit 81 will be described. The pressure variable unit 81 is controlled by the control unit 42.

[0245] As Figure 32 shown, when performing pressurized cleaning, the control unit 42 causes the pressure variable unit 81 to operate from step S1 to step S12. Steps S1 to S12 respectively show the states of the pressure variable unit 81. The control unit 42 rotates the camshaft 122 one full turn from step S1 to step S12. In one example, the state of the selection valve 107 changes every time the camshaft 122 rotates 45°.

[0246] Step S1 shows the standby state of the pressure variable unit 81. When pressure cleaning is not being performed, the pressure variable unit 81 stands by in the state of step S1. In step S1, the rotation angle of the camshaft 122 is 0°. In step S1, the camshaft 122 stands by at the reference angle. In step S1, the first motor 92 and the second motor 142 stop. In step S1, the open valve 110, the choke valve 112, and the pressure valve 111 are open. Therefore, in step S1, the choke air chamber C6 and the pressure air chamber C8 are open to the atmosphere. In step S1, the pump valve 109 is closed. Therefore, in step S1, the first pump 93 and the second pump 143 are disconnected from the flow unit 27. In step S1, the atmosphere opening portion 144 is open.

[0247] When starting pressure cleaning, the control unit 42 rotates the first motor 92 in the reverse direction. At this time, the control unit 42 rotates the camshaft 122 by 45°. As a result, the state of the pressure variable unit 81 transfers from step S1 to step S2.

[0248] In step S2, the rotation angle of the camshaft 122 is 45°. In step S2, the open valve 110 and the choke valve 112 are closed. In step S2, the pressure valve 111 and the pump valve 109 are open. Therefore, in step S2, the pressure unit 53 communicates with the first pump 93 and the second pump 143.

[0249] Next, the control unit 42 stops the first motor 92. The control unit 42 rotates the second motor 142 in the forward direction. As a result, the state of the pressure variable unit 81 transfers from step S2 to step S3.

[0250] In step S3, by rotating the second motor 142 in the forward direction, the atmosphere opening portion 144 is closed. In step S3, the pressure air chamber C8 is made negative pressure by the second pump 143. As a result, the liquid flows into the pressure liquid chamber C7.

[0251] Next, the control unit 42 rotates the first motor 92 in the reverse direction. At this time, the control unit 42 rotates the camshaft 122 by 45°. The control unit 42 stops the second motor 142. As a result, the state of the pressure variable unit 81 transfers from step S3 to step S4.

[0252] In step S4, the rotation angle of the camshaft 122 is 90°. In step S4, the open valve 110, the choke valve 112, and the pressure valve 111 are closed. By closing the pressure valve 111, the pressure air chamber C8 is maintained at negative pressure.

[0253] Next, the control unit 42 rotates the first motor 92 in the reverse direction. At this time, the control unit 42 rotates the camshaft 122 by 45°. As a result, the state of the pressure variable unit 81 transfers from step S4 to step S5.

[0254] In step S5, the rotation angle of the camshaft 122 is 135°. In step S5, the open valve 110 and the pressure valve 111 are closed. In step S5, the choke valve 112 and the pump valve 109 are open. Therefore, the first pump 93 and the second pump 143 communicate with the on-off valve 52. Therefore, the choke air chamber C6 is made negative pressure by the first pump 93.

[0255] Next, the control unit 42 stops the first motor 92. The control unit 42 rotates the second motor 142 forward. As a result, the state of the pressure variable unit 81 transfers from step S5 to step S6.

[0256] In step S6, the choke air chamber C6 is made negative pressure by the second pump 143. By decompressing the choke air chamber C6 from step S5 to step S6, the on-off valve 52 is closed.

[0257] Next, the control unit 42 rotates the first motor 92 in the reverse direction. At this time, the control unit 42 rotates the camshaft 122 by 45°. The control unit 42 stops the second motor 142. As a result, the state of the pressure variable unit 81 transfers from step S6 to step S7.

[0258] In step S7, the rotation angle of the camshaft 122 is 180°. In step S7, the open valve 110, the choke valve 112, and the pressure valve 111 are closed. By closing the choke valve 112, the choke air chamber C6 is maintained at negative pressure. Therefore, the on-off valve 52 remains closed.

[0259] Next, the control unit 42 rotates the first motor 92 in the reverse direction. At this time, the control unit 42 rotates the camshaft 122 by 45°. As a result, the state of the pressure variable unit 81 transfers from step S7 to step S8.

[0260] In step S8, the rotation angle of the camshaft 122 is 225°. In step S8, the open valve 110 and the pressure valve 111 are open. Therefore, the pressurized air chamber C8 is opened to the atmosphere. As a result, the liquid is extruded from the pressurized liquid chamber C7 toward the ejection unit 23. That is, the liquid is forcibly discharged from the nozzle 25.

[0261] Next, the control unit 42 stops the first motor 92. The control unit 42 rotates the second motor 142 in the reverse direction. As a result, the state of the pressure variable unit 81 transfers from step S8 to step S9.

[0262] In step S9, the atmosphere opening part 144 is opened by rotating the second motor 142 in the reverse direction. Therefore, in step S9, the pressurized air chamber C8 is opened to the atmosphere through the open pipe 104 and the atmosphere opening part 144.

[0263] Next, the control unit 42 rotates the first motor 92 in the reverse direction. At this time, the control unit 42 rotates the camshaft 122 by 45°. The control unit 42 stops the second motor 142. As a result, the state of the pressure variable unit 81 transfers from step S9 to step S10.

[0264] In step S10, the rotation angle of the camshaft 122 is 270°. In step S10, the open valve 110 and the pump valve 109 open. In step S10, the choke valve 112 and the pressure valve 111 close. By closing the pressure valve 111, the first pump 93 and the second pump 143 are disconnected from the pressurizing unit 53.

[0265] Next, the control unit 42 rotates the first motor 92 in the reverse direction. At this time, the control unit 42 rotates the camshaft 122 by 45°. Thereby, the state of the pressure variable unit 81 transfers from step S10 to step S11.

[0266] In step S11, the rotation angle of the camshaft 122 is 315°. In step S11, the open valve 110 and the choke valve 112 open. In step S11, the pressure valve 111 and the pump valve 109 close. By opening the choke valve 112, the choke air chamber C6 is opened to the atmosphere. Thereby, the on-off valve 52 opens.

[0267] Next, the control unit 42 rotates the first motor 92 in the reverse direction. At this time, the control unit 42 rotates the camshaft 122 by 45°. Thereby, the state of the pressure variable unit 81 transfers from step S11 to step S12.

[0268] In step S12, the rotation angle of the camshaft 122 is 360°, that is, 0°. Therefore, in step S12, the camshaft 122 rotates one full turn. In step S12, the open valve 110, the choke valve 112, and the pressure valve 111 open. In step S12, the pump valve 109 closes.

[0269] Finally, the control unit 42 stops the first motor 92. Thereby, the state of the pressure variable unit 81 transfers from step S12 to step S1. The control unit 42 ends the pressurized cleaning by stopping the first motor 92.

[0270] In the case of performing the liquid supply operation, the control unit 42 drives the flow path pump 71. The liquid supply operation is an operation of supplying liquid from the liquid container 20 to the liquid ejection unit 22. In the liquid supply operation, the control unit 42 does not operate the switching unit 94. For example, in the case of performing the liquid supply operation, the control unit 42 rotates the first motor 92 forward or stops the first motor 92. The control unit 42 alternately repeats the forward rotation and the stop of the first motor 92. The control unit 42 rotates the second motor 142 forward or rotates the second motor 142 in the reverse direction. When the control unit 42 rotates the first motor 92 forward, the control unit 42 rotates the second motor 142 forward. When the control unit 42 stops the first motor 92, the control unit 42 rotates the second motor 142 in the reverse direction. As a result, the pump air chamber C13 is depressurized or opened to the atmospheric pressure.

[0271] Functions and effects of the embodiment

[0272] Next, the functions and effects of the above embodiment will be described.

[0273] (1) The first transmission unit 123 is configured not to transmit power from the first motor 92 to the switching unit 94 when the first motor 92 rotates forward, and to transmit power from the first motor 92 to the switching unit 94 when the first motor 92 rotates in the reverse direction. According to the above configuration, the driving of the first pump 93 and the driving of the switching unit 94 are performed by one first motor 92. As a result, the possibility that the pressure variable unit 81 becomes large-sized is reduced.

[0274] (2) The switching unit 94 has a plurality of valves respectively located between a plurality of connection objects and the first pump 93. The switching unit 94 has a pump valve 109, an open valve 110, a pressure valve 111, and a choke valve 112. The switching unit 94 has a plurality of cams that respectively open and close the plurality of valves. The switching unit 94 has a pump cam 118, an open cam 119, a pressure cam 120, and a choke cam 121. According to the above configuration, the connection between a plurality of connection objects and the first pump 93 can be switched with a relatively simple configuration.

[0275] (3) The first transmission unit 123 has a one-way clutch 134. According to the above configuration, it is possible to configure relatively simply so that power is not transmitted from the first motor 92 to the switching unit 94 when the first motor 92 rotates forward, and power is transmitted from the first motor 92 to the switching unit 94 when the first motor 92 rotates in the reverse direction.

[0276] (4) The pressure variable unit 81 includes a second motor 142, a second pump 143, an atmosphere opening portion 144, and a second transmission portion 148. The second pump 143 is driven by the power of the second motor 142. The atmosphere opening portion 144 is connected to a plurality of connection objects and opens the plurality of connection objects to the atmosphere. The second transmission portion 148 is located between the second motor 142 and the atmosphere opening portion 144 and transmits the power of the second motor 142 to the atmosphere opening portion 144. The atmosphere opening portion 144 is configured to close when the second motor 142 rotates forward and open when the second motor 142 rotates in reverse. According to the above configuration, the driving of the second pump 143 and the opening and closing of the atmosphere opening portion 144 are performed by one second motor 142. It is possible not only to change the pressure of the connection object by the first pump 93 and the second pump 143, but also to restore the pressure of the connection object to atmospheric pressure by the atmosphere opening portion 144. In this way, the pressure of the connection object can be changed more freely.

[0277] (5) When the control unit 42 rotates the first motor 92 forward, the control unit 42 performs opening control on the first motor 92. When the control unit 42 rotates the first motor 92 in reverse, the control unit 42 performs PID control on the first motor 92 based on the detection result of the detection unit 135. According to the above configuration, by performing PID control on the first motor 92, it is possible to switch the connection between the plurality of connection objects and the first pump 93 with high precision.

[0278] (6) At least one of the liquid supply unit 30 and the liquid ejection unit 22 has a housing portion 28 that houses liquid. The housing portion 28 has a film member 29 that divides the inside of the housing portion 28 into an air chamber C2 and a liquid chamber C1. The plurality of connection objects include the housing portion 28. The pressure variable unit 81 changes the pressure of the air chamber C2. According to the above configuration, by changing the pressure of the air chamber C2 by the pressure variable unit 81, the pressure of the liquid chamber C1 changes. For example, when the liquid chamber C1 is pressurized, the liquid is discharged from the liquid chamber C1. When the liquid chamber C1 is depressurized, the liquid flows into the liquid chamber C1. In this way, the pressure variable unit 81 can control the flow of the liquid by changing the pressure of the air chamber C2.

[0279] (7) The plurality of housing portions 28 are respectively provided in the liquid supply unit 30 or the liquid ejection unit 22. The pressure variable unit 81 selectively changes the pressure of the plurality of air chambers C2. According to the above configuration, the pressure variable unit 81 can finely control the flow of the liquid.

[0280] (8) The fixing member 41 is detachably attached to and detached from the pressure variable unit 81 and the frame 32 from above. According to the above configuration, by approaching the fixing member 41 from above, it is easy to detach and attach the pressure variable unit 81 with respect to the frame 32.

[0281] The upstream ends of the first flexible member 169 and the second flexible member 170 are located on one side with respect to the center of the movement area A1 of the liquid ejection unit 22. According to the above configuration, the upstream ends of the first flexible member 169 and the second flexible member 170 are concentratedly arranged. The first flexible member 169 and the second flexible member 170 extend toward the flow portion 27. Therefore, the possibility that the length of the first flexible member 169 deviates significantly from the length of the second flexible member 170 is reduced. By making the length of the first flexible member 169 close to the length of the second flexible member 170, it is easy to align the first flexible member 169 and the second flexible member 170. Thereby, the space occupied by the first flexible member 169 and the second flexible member 170 can be reduced.

[0282] (10)The bundling body 175 has a holding portion 176 that holds the first flexible member 169 and a supporting portion 177 that supports the second flexible member 170. The supporting portion 177 has a pulley 179 that contacts the second flexible member 170. According to the above configuration, the possibility that the second flexible member 170 is damaged due to friction with the first flexible member 169 and the bundling body 175 is reduced.

[0283] (11)The pulley 179 has flanges 180 at both axial ends. According to the above configuration, the possibility that the second flexible member 170 contacts parts other than the pulley 179 is reduced by the flanges 180.

[0284] (12)The first flexible member 169 is a liquid pipe that supplies liquid to the liquid ejection unit 22. According to the above configuration, the bundling body 175 can hold the liquid pipe.

[0285] (13)The second flexible member 170 is an air pipe that supplies air to the liquid ejection unit 22. According to the above configuration, the possibility of wear of the air pipe is reduced.

[0286] (14)The liquid pipe has a first extension portion 171 and a first bending portion 172. The first extension portion 171 extends in the scanning direction D1, and the first bending portion 172 is bent into an arc shape from the first extension portion 171 toward the liquid ejection unit 22. The holding portion 176 holds the first extension portion 171. The supporting portion 177 supports the air pipe at a position closer to the liquid ejection unit 22 than the holding portion 176. According to the above configuration, by the supporting portion 177 supporting the air pipe at a position closer to the liquid ejection unit 22 than the holding portion 176, the curvature of the air pipe is made greater than the curvature of the liquid pipe. Compared with the liquid pipe, the air pipe can select a material with better bendability from the perspective of its barrier property. Therefore, it is okay even if the curvature of the air pipe is greater than the curvature of the liquid pipe. By the supporting portion 177 supporting the air pipe at a position closer to the liquid ejection unit 22 than the holding portion 176, the space occupied by the air pipe and the liquid pipe can be reduced.

[0287] 2. Embodiment 2

[0288] As Figure 34 shown, the liquid ejection device 211 includes a liquid ejection unit 212. The liquid ejection unit 212 is configured to eject liquid. The liquid ejection unit 212 prints an image on the medium M21 by ejecting liquid onto the medium M21.

[0289] Liquid is supplied from the liquid container 213 to the liquid ejection unit 212. The liquid container 213 stores liquid. The liquid container 213 is, for example, an ink cartridge, an ink tank, etc. The liquid container 213 is attached to the liquid ejection device 211. The liquid ejection device 211 is configured to be able to attach the liquid container 213.

[0290] The liquid ejection unit 212 has an ejection portion 214. The ejection portion 214 has a nozzle surface 215. The nozzle surface 215 is a surface facing the medium M21. One or more nozzles 216 are open on the nozzle surface 215. The ejection portion 214 ejects liquid from the nozzles 216.

[0291] The liquid ejection device 211 includes one or more storage portions 217 connected to the ejection portion 214. In one example, the liquid ejection device 211 includes a plurality of storage portions 217. The storage portion 217 is configured to store liquid. The storage portion 217 is located between the liquid container 213 and the ejection portion 214. The storage portion 217 stores liquid between the liquid container 213 and the ejection portion 214. The storage portion 217 is, for example, an on-off valve 223, a pressurizing portion 224, a flow path pump 244. The on-off valve 223, the pressurizing portion 224, and the flow path pump 244 will be described later.

[0292] Based on Figure 35 , a common configuration of the storage portion 217 will be described. As Figure 35 shown, the storage portion 217 has a film member 218. The film member 218 is a flexible member. The film member 218 can be deformed. The film member 218 divides the inside of the storage portion 217 into a liquid chamber C21 and an air chamber C22. The liquid chamber C21 is a space for storing liquid. The air chamber C22 is a space for storing air. The film member 218 separates the liquid chamber C21 and the air chamber C22. The film member 218 forms the wall surface of the liquid chamber C21 and the wall surface of the air chamber C22. The film member 218 deforms according to the pressure in the liquid chamber C21 and the pressure in the air chamber C22. When the film member 218 deforms, the volume of the liquid chamber C21 and the volume of the air chamber C22 change.

[0293] A plurality of openings are formed in the accommodating portion 217. Liquid and air are supplied into the accommodating portion 217 through the plurality of openings, or liquid and air are discharged from the accommodating portion 217. In one example, the inflow port H21, the outflow port H22, and the air port H23 open in the accommodating portion 217. The inflow port H21 communicates with the liquid chamber C21. Liquid flows into the liquid chamber C21 through the inflow port H21. The outflow port H22 communicates with the liquid chamber C21. Liquid flows out of the liquid chamber C21 through the outflow port H22. The air port H23 communicates with the air chamber C22. Air is supplied into the air chamber C22 through the air port H23, or air is discharged from the air chamber C22. That is, the air chamber C22 is pressurized or depressurized through the air port H23. When the air chamber C22 is pressurized, the membrane member 218 deforms in such a manner as to reduce the volume of the liquid chamber C21. Thereby, liquid flows out of the liquid chamber C21 through the outflow port H22. When the air chamber C22 is depressurized, the membrane member 218 deforms in such a manner as to increase the volume of the liquid chamber C21. Thereby, liquid flows into the liquid chamber C21 through the inflow port H21.

[0294] As Figure 34 shown, the liquid ejection unit 212 has a flow portion 221. The flow portion 221 allows the liquid supplied to the ejection portion 214 to flow. The flow portion 221 is connected to the ejection portion 214. The flow portion 221 is located between the liquid container 213 and the ejection portion 214.

[0295] The flow portion 221 may also have an adjustment valve 222. The adjustment valve 222 is configured to open and close. The adjustment valve 222 is normally closed. By opening the adjustment valve 222, liquid flows into the flow portion 221.

[0296] The adjustment valve 222 is configured to adjust the pressure in the ejection portion 214. In one example, the adjustment valve 222 is configured to adjust the pressure in the flow portion 221. The adjustment valve 222 opens and closes based on the pressure in the flow portion 221, thereby adjusting the pressure in the flow portion 221. The adjustment valve 222 adjusts the pressure in the ejection portion 214 by adjusting the pressure in the flow portion 221.

[0297] The adjustment valve 222 is configured to open and close using the differential pressure between the pressure in the ejection portion 214 and the atmospheric pressure. In one example, the adjustment valve 222 opens and closes using the differential pressure between the pressure in the flow portion 221 and the atmospheric pressure. Specifically, the adjustment valve 222 opens when the pressure downstream of itself is equal to or lower than a specified pressure. That is, the adjustment valve 222 opens when the pressure in the flow portion 221 is equal to or lower than a specified pressure. The adjustment valve 222 closes when the pressure in the flow portion 221 is greater than the specified pressure.

[0298] The regulating valve 222 maintains a prescribed pressure in the flow portion 221 by opening and closing. The regulating valve 222 maintains a prescribed pressure in the ejection portion 214 by maintaining a prescribed pressure in the flow portion 221. The operating pressure at which the regulating valve 222 opens is a prescribed negative pressure. Therefore, the regulating valve 222 maintains a prescribed negative pressure in the ejection portion 214. By maintaining a prescribed negative pressure in the ejection portion 214, a meniscus is formed at the nozzle 216. By forming a meniscus at the nozzle 216, the ejection portion 214 can eject the liquid well.

[0299] The operating pressure of the regulating valve 222 is greater than the meniscus withstand pressure. Therefore, the ejection portion 214 is maintained at a negative pressure that can maintain the meniscus by the regulating valve 222. When the negative pressure in the ejection portion 214 exceeds the meniscus withstand pressure, that is, when the pressure in the ejection portion 214 is lower than the meniscus withstand pressure, the meniscus may be damaged. When the meniscus is damaged, air may flow into the ejection portion 214 through the nozzle 216.

[0300] The flow portion 221 has one or more accommodating portions 217. The flow portion 221 has, for example, an opening / closing valve 223 and a pressurizing portion 224. The opening / closing valve 223 and the pressurizing portion 224 are an example of the accommodating portion 217. The opening / closing valve 223 and the pressurizing portion 224 are located downstream of the regulating valve 222. In the flow portion 221, the liquid is supplied to the ejection portion 214 through the regulating valve 222, the opening / closing valve 223, and the pressurizing portion 224 in sequence.

[0301] The opening / closing valve 223 is connected to the regulating valve 222. The opening / closing valve 223 is connected to the pressurizing portion 224. The opening / closing valve 223 is connected to the ejection portion 214 through the pressurizing portion 224. The opening / closing valve 223 is configured to open and close. Different from the regulating valve 222, the opening / closing valve 223 is configured to open and close arbitrarily. The opening / closing valve 223 is closed by changing the pressure in the air chamber C22. When cleaning the ejection portion 214, the opening / closing valve 223 is closed. Specifically, the opening / closing valve 223 is closed when the pressurizing portion 224 cleans the ejection portion 214. The opening / closing valve 223 is usually open.

[0302] The pressurizing section 224 is connected to the on-off valve 223. The pressurizing section 224 is connected to the ejection section 214. The pressurizing section 224 is configured to pressurize the inside of the ejection section 214. The pressurizing section 224 pressurizes the inside of the ejection section 214 by changing the pressure in the air chamber C22 of the pressurizing section 224. The pressurizing section 224 cleans the ejection section 214 by pressurizing the inside of the ejection section 214. Specifically, the pressurizing section 224 causes the liquid to be discharged from the nozzle 216 by pressurizing the inside of the ejection section 214. Thereby, the thickened liquid, foreign matter, etc. are discharged from the inside of the ejection section 214. By closing the on-off valve 223 when the pressurizing section 224 pressurizes the inside of the ejection section 214, the possibility of the liquid flowing back from the pressurizing section 224 is reduced. By closing the on-off valve 223, that is, by blocking the flow, the pressurizing section 224 can effectively pressurize the inside of the ejection section 214.

[0303] As Figure 36 shown, the flow section 221 has a flow component 225. The flow component 225 also delimits a space for accommodating the liquid. The flow component 225 is a component that delimits a space for accommodating air. In one example, the flow component 225 constitutes the on-off valve 223 and the pressurizing section 224. The flow component 225 can also constitute the regulating valve 222.

[0304] The flow component 225 delimits a flow-blocking space C23. The flow-blocking space C23 is the space inside the on-off valve 223. A flow-blocking flow inlet H24 and a flow-blocking flow outlet H25 are open in the flow component 225. The flow-blocking flow inlet H24 is an example of the flow inlet H21. The flow-blocking flow outlet H25 is an example of the flow outlet H22. A flow-blocking air port H26 is open in the flow component 225. The flow-blocking air port H26 is an example of the air port H23.

[0305] The flow component 225 delimits a pressurizing space C24. The pressurizing space C24 is the space inside the pressurizing section 224. A pressurizing flow inlet H27 and a pressurizing flow outlet H28 are open in the flow component 225. The pressurizing flow inlet H27 is an example of the flow inlet H21. The pressurizing flow outlet H28 is an example of the flow outlet H22. A pressurizing air port H29 is open in the flow component 225. The pressurizing air port H29 is an example of the air port H23.

[0306] The flow section 221 has a flow-blocking membrane 226. The flow-blocking membrane 226 is mounted on the flow component 225. The flow-blocking membrane 226 is an example of the membrane component 218. The flow-blocking membrane 226 constitutes the on-off valve 223. The flow-blocking membrane 226 divides the flow-blocking space C23 into a flow-blocking liquid chamber C25 and a flow-blocking air chamber C26. The flow-blocking liquid chamber C25 is an example of the liquid chamber C21. The flow-blocking liquid chamber C25 communicates with the flow-blocking flow inlet H24 and the flow-blocking flow outlet H25. The flow-blocking air chamber C26 is an example of the air chamber C22. The flow-blocking air chamber C26 communicates with the flow-blocking air port H26.

[0307] The flow blocking film 226 has a valve portion 227 and an actuating portion 228. The valve portion 227 is the portion that blocks the flow blocking inlet H24 or the flow blocking outlet H25. In one example, the valve portion 227 blocks the flow blocking outlet H25. The valve portion 227 blocks the flow blocking outlet H25 by being pressed by a rod 229 described later. The actuating portion 228 is the portion that actuates the rod 229.

[0308] The actuating portion 228 is configured to be more deformable than the valve portion 227. In one example, the actuating portion 228 is configured to have a smaller elasticity than the valve portion 227. For example, the thickness of the actuating portion 228 may also be smaller than the thickness of the valve portion 227. The area of the actuating portion 228 facing the flow blocking air chamber C26 may also be larger than the area of the valve portion 227 facing the flow blocking air chamber C26.

[0309] When the flow blocking air chamber C26 is decompressed, the valve portion 227 and the actuating portion 228 deform in such a way as to reduce the volume of the flow blocking air chamber C26. At this time, the actuating portion 228 is more deformable than the valve portion 227.

[0310] The flow portion 221 has a rod 229. The rod 229 constitutes an opening / closing valve 223. The rod 229 is mounted on the flow member 225. The rod 229 is located in the flow blocking space C23. Specifically, the rod 229 is located in the flow blocking air chamber C26. The rod 229 has, for example, a shaft portion 230. The shaft portion 230 is mounted on the flow member 225. The rod 229 is displaced about the shaft portion 230. The rod 229 is displaced in the flow blocking air chamber C26.

[0311] The rod 229 has a first portion 231 and a second portion 232. The first portion 231 is the portion including one end of the rod 229. The first portion 231 is located at a position in contact with the valve portion 227. The second portion 232 is the portion including the other end of the rod 229. The second portion 232 is located at a position in contact with the actuating portion 228.

[0312] When the flow blocking air chamber C26 is decompressed, the valve portion 227 deforms in such a way as to push up the first portion 231. The actuating portion 228 deforms in such a way as to push up the second portion 232. Since the actuating portion 228 is more deformable than the valve portion 227, the force with which the actuating portion 228 pushes up the rod 229 is greater than the force with which the valve portion 227 pushes up the rod 229. Therefore, the rod 229 is displaced in such a way that the first portion 231 presses down on the valve portion 227. That is, the rod 229 presses the valve portion 227 against the flow blocking outlet H25. Thereby, the flow blocking outlet H25 is blocked.

[0313] The flow unit 221 has a pressurizing membrane 233. The pressurizing membrane 233 is installed on the flow component 225. The pressurizing membrane 233 is an example of the membrane component 218. The pressurizing membrane 233 constitutes the pressurizing section 224. The pressurizing membrane 233 divides the pressurizing space C24 into a pressurized liquid chamber C27 and a pressurized air chamber C28. The pressurized liquid chamber C27 is an example of the liquid chamber C21. The pressurized liquid chamber C27 communicates with a pressurized liquid inlet H27 and a pressurized liquid outlet H28. The pressurized air chamber C28 is an example of the air chamber C22. The pressurized air chamber C28 communicates with a pressurized air port H29.

[0314] The flow unit 221 may also have a pressurizing member 234. The pressurizing member 234 is configured to press the pressurizing membrane 233. Specifically, the pressurizing member 234 presses the pressurizing membrane 233 in such a way as to reduce the volume of the pressurized liquid chamber C27. The pressurizing member 234 is located in the pressurized air chamber C28. The pressurizing member 234 is installed on the flow component 225 and the pressurizing membrane 233.

[0315] When the pressurized air chamber C28 is depressurized, the pressurizing membrane 233 is displaced in such a way as to reduce the volume of the pressurized air chamber C28. At this time, the pressurizing membrane 233 is displaced in such a way as to increase the volume of the pressurized liquid chamber C27. As a result, the liquid flows into the pressurized liquid chamber C27. Specifically, the liquid flows into the pressurized liquid chamber C27 from the ejection section 214, the adjustment valve 222, the on-off valve 223, etc. When the pressurized air chamber C28 is pressurized or opened to the atmosphere, the pressurizing membrane 233 is deformed in such a way as to reduce the volume of the pressurized liquid chamber C27. At this time, the liquid in the pressurized liquid chamber C27 is pressurized. As a result, the liquid is discharged from the nozzle 216.

[0316] As Figure 34 shown, the liquid ejection unit 212 may also have a moving body 236. The moving body 236 carries the ejection section 214. The moving body 236 carries the flow unit 221. The moving body 236 is capable of moving. The moving body 236 moves in the scanning direction with respect to the medium M21. The liquid ejection unit 212 is a serial head capable of ejecting liquid over the entire width of the medium M21. The liquid ejection unit 212 may also be a line head capable of ejecting liquid over the entire width of the medium M21 all at once.

[0317] The liquid ejection device 211 includes a liquid supply unit 241. The liquid supply unit 241 is connected to the liquid container 213 and the liquid ejection unit 212. The liquid supply unit 241 is configured to supply liquid to the liquid ejection unit 212.

[0318] The liquid supply unit 241 has a supply flow path 242. The supply flow path 242 is a flow path through which liquid flows. Specifically, the supply flow path 242 is a flow path through which the liquid supplied to the ejection unit 214 flows. Liquid is supplied to the liquid ejection unit 212 through the supply flow path 242. The supply flow path 242 is connected to the liquid container 213 and the liquid ejection unit 212. In one example, the supply flow path 242 is connected to the liquid container 213 and the flow unit 221.

[0319] The liquid supply unit 241 may also have a supply valve 243. In one example, the liquid supply unit 241 has a supply valve 243. The supply valve 243 is located in the supply flow path 242. Specifically, the supply valve 243 is located between the liquid container 213 and a flow path pump 244 described later. The supply valve 243 is a valve that controls the flow of liquid in the supply flow path 242. The supply valve 243 is, for example, a one-way valve. The supply valve 243 allows liquid to flow in the supply flow path 242 from the liquid container 213 toward the liquid ejection unit 212. The supply valve 243 restricts the flow of liquid in the supply flow path 242 from the liquid ejection unit 212 toward the liquid container 213. The supply valve 243 may also be an electromagnetic valve that can be arbitrarily opened and closed.

[0320] The liquid supply unit 241 has a flow path pump 244. The flow path pump 244 is an example of the accommodating unit 217. The flow path pump 244 is a so-called diaphragm pump. The flow path pump 244 is located in the supply flow path 242. The flow path pump 244 is located between the liquid container 213 and the liquid ejection unit 212. Specifically, the flow path pump 244 is located between the supply valve 243 and the liquid ejection unit 212. The flow path pump 244 is configured to supply liquid from the liquid container 213 toward the liquid ejection unit 212. The flow path pump 244 supplies liquid from the liquid container 213 toward the liquid ejection unit 212 by changing the air chamber C22 of the flow path pump 244.

[0321] The flow path pump 244 has a diaphragm 245 as an example of a membrane component. The diaphragm 245 divides the inside of the flow path pump 244 into a flow path liquid chamber C211 and a flow path air chamber C212. The flow path liquid chamber C211 is an example of the liquid chamber C1. The flow path air chamber C212 is an example of the air chamber C22.

[0322] The flow path pump 244 has a pressing member 246. The pressing member 246 is configured to press the diaphragm 245. Specifically, the pressing member 246 presses the diaphragm 245 in such a manner that the volume of the flow path liquid chamber C211 becomes smaller. That is, the pressing member 246 presses the diaphragm 245 in a manner that pressurizes the flow path liquid chamber C211. The pressing member 246 is located in the flow path air chamber C212.

[0323] When the flow path air chamber C212 is decompressed, the diaphragm 245 deforms in a manner that increases the volume of the flow path liquid chamber C211. As a result, the liquid flows from the liquid container 213 into the flow path liquid chamber C211. When the flow path air chamber C212 is pressurized or opened to the atmosphere, the pressing member 246 causes the diaphragm 245 to deform in a manner that decreases the volume of the flow path liquid chamber C211. As a result, the liquid flows out from the flow path liquid chamber C211 toward the flow portion 221.

[0324] The liquid supply unit 241 includes a pressure variable unit 247. The pressure variable unit 247 is connected to the accommodating portion 217. In one example, the pressure variable unit 247 is connected to the on-off valve 223, the pressurizing unit 224, and the flow path pump 244 respectively.

[0325] The pressure variable unit 247 is configured to change the pressure in the accommodating portion 217. In one example, the pressure variable unit 247 is configured to change the pressure in any one of the plurality of accommodating portions 217. The pressure variable unit 247 changes the pressure in the air chamber C22. In one example, the pressure variable unit 247 decompresses the air chamber C22.

[0326] The pressure variable unit 247 includes a decompression pump 248. The decompression pump 248 is a pump that generates a negative pressure. The decompression pump 248 is connected to the accommodating portion 217. The decompression pump 248 decompresses the air chamber C22.

[0327] The pressure variable unit 247 includes a motor 249. The motor 249 is connected to the decompression pump 248. The motor 249 drives the decompression pump 248. That is, the decompression pump 248 is driven by the power of the motor 249. The motor 249 operates by PWM control, for example.

[0328] The liquid supply unit 241 includes an air flow path 250. The air flow path 250 is connected to the pressure variable unit 247 and the accommodating portion 217. In one example, the air flow path 250 is connected to the decompression pump 248 and the on-off valve 223. The air flow path 250 is connected to the decompression pump 248 and the pressurizing unit 224. The air flow path 250 is connected to the decompression pump 248 and the flow path pump 244. The decompression pump 248 decompresses the air chamber C22 through the air flow path 250.

[0329] The liquid supply unit 241 has one or more air valves. In one example, the liquid supply unit 241 has a first air valve 251, a second air valve 252, and a third air valve 253. The air valves are located in the air flow path 250. The air valves are configured to open and close. The air valves are, for example, electromagnetic valves. The first air valve 251 is located between the decompression pump 248 and the on-off valve 223. When the first air valve 251 is opened, the on-off valve 223 can be decompressed by the decompression pump 248. The second air valve 252 is located between the decompression pump 248 and the pressurizing unit 224. When the second air valve 252 is opened, the pressurizing unit 224 can be decompressed by the decompression pump 248. The third air valve 253 is located between the decompression pump 248 and the flow path pump 244. When the third air valve 253 is opened, the flow path pump 244 can be decompressed by the decompression pump 248.

[0330] The liquid supply unit 241 has an atmosphere open valve 254. The atmosphere open valve 254 is connected to the air flow path 250. The atmosphere open valve 254 is configured to open and close. The atmosphere open valve 254 is, for example, an electromagnetic valve. When the atmosphere open valve 254 is opened, the air flow path 250 is opened to the atmosphere. The accommodation part 217 is opened to the atmosphere through the air flow path 250. Specifically, when the atmosphere open valve 254 and the first air valve 251 are opened, the on-off valve 223 is opened to the atmosphere. When the atmosphere open valve 254 and the second air valve 252 are opened, the pressurizing unit 224 is opened to the atmosphere. When the atmosphere open valve 254 and the third air valve 253 are opened, the flow path pump 244 is opened to the atmosphere.

[0331] The liquid ejection device 211 includes a power supply circuit 256. The power supply circuit 256 is connected to the liquid supply unit 241. The power supply circuit 256 is connected to the pressure variable unit 247. The power supply circuit 256 is connected to the motor 249. The power supply circuit 256 applies a voltage to the motor 249. The power supply circuit 256 applies an arbitrary voltage to the motor 249. By applying a voltage to the motor 249 through the power supply circuit 256, the motor 249 starts.

[0332] The liquid ejection device 211 includes a control unit 257. The control unit 257 controls the liquid supply unit 241. The control unit 257 controls the pressure variable unit 247. The control unit 257 controls the power supply circuit 256. The control unit 257 controls the voltage applied to the motor 249 by controlling the power supply circuit 256. The control unit 257 controls the applied voltage by PWM control. The control unit 257 controls the decompression pump 248 by controlling the applied voltage. Thus, the control unit 257 controls the negative pressure generated by the decompression pump 248.

[0333] The control unit 257 controls the air valve. The control unit 257 controls the operation of the accommodation unit 217 by controlling the air valve. The control unit 257 controls the atmosphere opening valve 254. The control unit 257 controls the operation of the accommodation unit 217 by controlling the atmosphere opening valve 254. The control unit 257 decompresses an arbitrary accommodation unit 217 or opens it to the atmosphere by controlling the air valve and the atmosphere opening valve 254. Thus, the control unit 257 controls the flow of the liquid.

[0334] The control unit 257 performs cleaning by controlling the operation of the on-off valve 223 and the pressurizing unit 224. In one example, first, the control unit 257 opens the second air valve 252. Next, the control unit 257 starts the motor 249. As a result, the pressurized air chamber C28 is decompressed by the decompression pump 248. As a result, the liquid flows into the pressurized liquid chamber C27. Next, the control unit 257 closes the second air valve 252. As a result, the pressurized air chamber C28 is maintained at a negative pressure. Next, the control unit 257 opens the first air valve 251. As a result, the choke air chamber C26 is decompressed by the decompression pump 248. As a result, the on-off valve 223 closes. Next, the control unit 257 opens the second air valve 252 and the atmosphere opening valve 254. As a result, the pressurized air chamber C28 is opened to the atmosphere. As a result, the liquid is discharged from the nozzle 216.

[0335] The control unit 257 supplies liquid to the liquid ejection unit 212 by controlling the flow path pump 244. In one example, first, the control unit 257 opens the third air valve 253. Next, the control unit 257 starts the motor 249. As a result, the flow path air chamber C212 is decompressed by the decompression pump 248. As a result, the liquid flows from the liquid container 213 into the flow path liquid chamber C211. Next, the control unit 257 opens the atmosphere opening valve 254. As a result, the flow path air chamber C212 is opened to the atmosphere. As a result, the diaphragm 245 pressurizes the liquid in the flow path liquid chamber C211. Therefore, the liquid flows out from the flow path liquid chamber C211 toward the liquid ejection unit 212.

[0336] The control unit 257 is not limited to controlling the liquid supply unit 241, and can also control the liquid ejection unit 212. The control unit 257 can also comprehensively control the liquid ejection device 211. The control unit 257 can also be composed of one or more processors that execute various processes according to a computer program. The control unit 257 can also be composed of one or more dedicated hardware circuits such as an ASIC that executes at least a part of the various processes. The control unit 257 can also be composed of a circuit including a combination of a processor and a hardware circuit. The processor includes a CPU and memories such as a RAM and a ROM. The memory stores program codes or instructions configured to cause the CPU to execute processes. The memory, that is, the computer-readable medium includes all readable media accessible by a general-purpose or dedicated computer.

[0337] Control of applied voltage

[0338] Next, the control of the applied voltage by the control unit 257 will be described. When the flow is blocked by the on-off valve 223, the control unit 257 drives the motor 249 at the target voltage. When the ejection unit 214 is cleaned by the pressurizing unit 224, the control unit 257 drives the motor 249 at the target voltage. When a liquid is supplied to the ejection unit 214 by the flow path pump 244, the control unit 257 drives the motor 249 at the target voltage. By driving the motor 249 at the target voltage, the accommodation unit 217 can be sufficiently depressurized.

[0339] When the accommodation unit 217 is depressurized, the negative pressure in the accommodation unit 217 sometimes acts on the ejection unit 214. Therefore, when the accommodation unit 217 is rapidly depressurized, the liquid meniscus of the nozzle 216 may be damaged. In one example, when the pressurizing unit 224 is depressurized, the negative pressure in the pressurizing unit 224 acts on the ejection unit 214 until the adjustment valve 222 is opened. When the pressurizing unit 224 is rapidly depressurized, the liquid meniscus of the nozzle 216 may be damaged. Therefore, the control unit 257 controls the applied voltage to the motor 249 to depressurize the accommodation unit 217 in a manner that does not damage the liquid meniscus.

[0340] As Figure 37 shown, the control unit 257 gradually increases the applied voltage until the applied voltage to the motor 249 reaches the target voltage. Specifically, the control unit 257 increases the applied voltage over a specified time to reach the target voltage. As a result, the decompression pump 248 gradually depressurizes the pressurizing unit 224. Therefore, the possibility of damaging the liquid meniscus is reduced. The control unit 257 performs PWM control on the applied voltage to the motor 249, for example. The control unit 257 controls the applied voltage to the motor 249 by controlling the duty ratio through the power supply circuit 256.

[0341] As Figure 38 shown, the control unit 257 gradually increases the applied voltage to gradually depressurize the pressurized air chamber C28. Figure 38 The solid line curve in Figure 38 shows the pressure change of the pressurized air chamber C28 when the applied voltage is gradually increased.

[0342] As Figure 39 shown, the control unit 257 gradually increases the applied voltage to depressurize the pressurized liquid chamber C27 in a manner that the pressure in the pressurized liquid chamber C27 does not exceed the liquid meniscus pressure resistance. The liquid meniscus pressure resistance is, for example, -2.0 kPa. The operating pressure of the adjustment valve 222 is, for example, -1.0 kPa. In Figure 39In the shown graph, the pressure in the pressurizing liquid chamber C27 changes in a manner that it rises after being lower than -1.0 kPa. This is because liquid flows into the pressurizing liquid chamber C27 by opening the regulating valve 222.

[0343] The control unit 257 gradually increases the applied voltage until it reaches the target voltage to prevent the pressure in the ejection part 214 from being lower than the meniscus pressure resistance when the air chamber C22 is depressurized by the vacuum pump 248. In one example, the control unit 257 gradually increases the applied voltage to prevent the pressure in the ejection part 214 from being lower than -2.0 kPa when the pressurized air chamber C28 is depressurized by the vacuum pump 248. The pressure in the ejection part 214 is usually maintained at the operating pressure of the regulating valve 222. Therefore, the pressure in the ejection part 214 is usually -1.0 kPa. That is, the control unit 257 gradually increases the applied voltage to prevent the negative pressure acting on the ejection part 214 by the vacuum pump 248 from exceeding -1.0 kPa. The control unit 257 gradually increases the applied voltage to prevent the sum of the negative pressure acting on the ejection part 214 by the vacuum pump 248 and the operating pressure from exceeding the meniscus pressure resistance.

[0344] As Figure 37 shown, the control unit 257 controls such that the applied voltage gradually increases starting from a voltage lower than the starting voltage of the motor 249. Specifically, the control unit 257 controls such that the applied voltage gradually increases starting from a voltage lower than the starting voltage range. That is, the control unit 257 makes the starting voltage applied to the motor 249 lower than the starting voltage. The starting voltage is the voltage at which the motor 249 starts to rotate. The starting voltage range is the voltage range indicating the starting voltage. In the motor 249, there is a deviation in the starting voltage. The starting voltage is the applied voltage at the time point when the application starts. By increasing the applied voltage starting from a voltage lower than the starting voltage, the possibility that the motor 249 starts to rotate violently just after the application starts is reduced. That is, the possibility that the pressurizing part 224 is rapidly depressurized by the motor 249 with a small starting voltage is reduced.

[0345] The control unit 257 makes the applied voltage rise at a constant slope during the period from the start of applying voltage to the motor 249 until a specified time has elapsed. The specified time is the time until the applied voltage becomes greater than the starting voltage. Specifically, the specified time is the time required until the negative pressure generated by the vacuum pump 248 acts on the accommodating part 217. By elapsing the specified time, the motor 249 starts regardless of the deviation of the starting voltage. Just after the motor 249 starts, sometimes the negative pressure generated by the vacuum pump 248 does not act on the pressurized air chamber C28. Therefore, the specified time needs to be longer than the time until the applied voltage reaches the starting voltage. By elapsing the specified time while maintaining a constant slope of the applied voltage, the vacuum pump 248 can gently depressurize the pressurized air chamber C28.

[0346] The control unit 257 increases the slope of the applied voltage after a predetermined time has elapsed. As a result, the time required for the applied voltage to reach the target voltage is shortened.

[0347] After the control unit 257 increases the slope of the applied voltage, it maintains the applied voltage at a relay voltage lower than the target voltage for a certain period of time. If the applied voltage rises sharply to the target voltage after increasing the slope of the applied voltage, the negative pressure in the ejection unit 214 may exceed the meniscus withstand voltage. By having the applied voltage standby at the relay voltage, the possibility of the pressurizing unit 224 being rapidly depressurized is reduced.

[0348] After the control unit 257 maintains the applied voltage at the relay voltage for a certain period of time, it causes the applied voltage to rise at a constant slope. For example, the control unit 257 causes the applied voltage to rise from the relay voltage toward the target voltage at the slope after a predetermined time has elapsed. As a result, the time required for the applied voltage to reach the target voltage is shortened. The applied voltage changes stepwise through the relay voltage. The control unit 257 may also cause the applied voltage to change via multiple relay voltages.

[0349] Functions and effects of the embodiment

[0350] Next, the functions and effects of the above embodiment will be described.

[0351] (15) The control unit 257 gradually raises the applied voltage until the applied voltage to the motor 249 reaches the target voltage. According to the above configuration, since the air chamber C22 is gradually depressurized, the possibility of liquid flowing rapidly from the ejection unit 214 to the liquid chamber C21 is reduced. Therefore, the possibility of air flowing into the ejection unit 214 from the nozzle 216 is reduced.

[0352] (16) The control unit 257 starts raising the applied voltage from a voltage lower than the starting voltage of the motor 249. Generally, there are deviations in the starting voltage of the motor 249. According to the above configuration, the possibility of the motor 249 starting immediately after the applied voltage is first applied to the motor 249 is reduced. Therefore, even when there are deviations in the starting voltage of the motor 249, the possibility of the air chamber C22 being rapidly depressurized is reduced.

[0353] (17) The control unit 257 raises the applied voltage at a constant slope during the period from when the applied voltage is first applied to the motor 249 until a predetermined time has elapsed. According to the above configuration, even when there are deviations in the starting voltage of the motor 249, the possibility of the air chamber C22 being rapidly depressurized is reduced.

[0354] (18) The control unit 257 increases the slope of the applied voltage after a specified time. According to the above configuration, compared with the case where the slope of the applied voltage remains constant, the time until the applied voltage reaches the target voltage is shortened.

[0355] (19) After the control unit 257 increases the slope of the applied voltage, it maintains the applied voltage at a relay voltage smaller than the target voltage for a certain period of time. When the slope of the applied voltage increases, the air chamber C22 may be rapidly depressurized. In this case, air may flow into the ejection unit 214 from the nozzle 216. Regarding this point, according to the above configuration, since the applied voltage is maintained at the relay voltage for a certain period of time, the possibility of the air chamber C22 being rapidly depressurized is reduced.

[0356] (20) The flow unit 221 has a housing unit 217. According to the above configuration, the flow of the liquid supplied to the ejection unit 214 can be controlled by the housing unit 217.

[0357] (21) The operating pressure of the adjustment valve 222 is greater than the meniscus pressure resistance. According to the above configuration, the adjustment valve 222 opens before the pressure in the liquid chamber C1 is lower than the meniscus pressure resistance. Therefore, the possibility of air flowing into the ejection unit 214 from the nozzle 216 is reduced.

[0358] Variation

[0359] The embodiment can be changed and implemented as follows. The above embodiment and the following variations can be implemented in combination with each other within a technically non - contradictory range.

[0360] The bundling body 175 is not limited to being applied to the liquid ejection unit 22, and can also be applied to flexible members connected to other units. That is, in order to gather a plurality of flexible members connected to the unit moving in the scanning direction D1, the bundling body 175 can also be used. The bundling body 175 can also be used, for example, to gather signal lines, flexible flat cables, etc. connected to the unit.

[0361] As Figure 33 shown, the switching unit 94 may also have a switching body 186. In this variation, the switching unit 94 has a switching body 186 instead of the flow path member 95. The switching body 186 is located between a plurality of connection objects of the pressure variable unit 81 and the first pump 93. The switching body 186 is configured to switch the connection between the plurality of connection objects and the first pump 93 by rotating. Similar to the flow path member 95, pump channels P1, open channels P2, pressurization channels P3, choke channels P4, and conduction channels P5 are defined in the switching body 186.

[0362] The switching body 186 has a switching base material 187 and a rotating body 188. The switching base material 187 has a plurality of switching tubes in the same manner as the flow path base material 96. The switching base material 187 has a pump tube 102, a flow path pump tube 103, an open tube 104, a pressure tube 105, and a blocking tube 106. The rotating body 188 is in close contact with the switching base material 187. The rotating body 188 rotates while being in close contact with the switching base material 187. When the rotating body 188 rotates, the switching pump tube 102, the flow path pump tube 103, the open tube 104, the pressure tube 105, and the blocking tube 106 are brought into conduction. For example, when the rotating body 188 rotates, the state where the pump tube 102 is in conduction with the pressure tube 105 is switched to the state where the pump tube 102 is in conduction with the blocking tube 106. According to such a switching body 186, the connection between a plurality of connection objects and the first pump 93 can be switched with a relatively simple configuration.

[0363] The liquid ejected from the ejection unit 23 is not limited to ink. For example, it may also be a liquid body in which particles of a functional material are dispersed or mixed in a liquid, or the like. For example, the ejection unit 23 may also eject a liquid body containing materials such as electrode materials or pixel materials used in the manufacture of liquid crystal displays, electroluminescent displays, and surface-emitting displays in a dispersed or dissolved form.

[0364] In the liquid ejection device 211, at least a part of the adjustment valve 222, the on-off valve 223, and the pressurizing unit 224 may be provided in the supply flow path 242. That is, one of the adjustment valve 222, the on-off valve 223, and the pressurizing unit 224 may be provided in the supply flow path 242, two of the adjustment valve 222, the on-off valve 223, and the pressurizing unit 224 may be provided in the supply flow path 242, or all of the adjustment valve 222, the on-off valve 223, and the pressurizing unit 224 may be provided in the supply flow path 242.

[0365] In the liquid ejection device 211, it is not limited to the adjustment valve 222. For example, the inside of the ejection unit 214 may be maintained at a negative pressure by a head difference. In this case, the flow unit 221 does not have the adjustment valve 222. In this modification example, the pressure in the flow path pump 244 acts on the inside of the ejection unit 214. Therefore, the control unit 257 may also gradually increase the applied voltage when driving the flow path pump 244. According to this modification example, the possibility of air flowing into the ejection unit 214 from the nozzle 216 is reduced. In addition, the liquid inside the ejection unit 214 can be returned to the supply flow path 242. Thereby, the liquid can be stirred.

[0366] The liquid ejected from the ejection unit 214 is not limited to ink. For example, it may also be a liquid body in which particles of a functional material are dispersed or mixed in a liquid, or the like. For example, the ejection unit 214 may also eject a liquid body containing materials such as electrode materials or pixel materials used in the manufacture of liquid crystal displays, electroluminescent displays, and surface-emitting displays in a dispersed or dissolved form.

[0367] Technical idea

[0368] Hereinafter, the technical ideas and their effects that can be grasped from the above-described embodiments and modified examples will be described.

[0369] (1) A pressure variable unit that changes the pressure of a plurality of connection targets, and includes: an electric motor; a pump connected to the electric motor and driven by the power of the electric motor; a switching unit that uses the power of the electric motor to switch the connection between the plurality of connection targets and the pump; and a transmission unit located between the electric motor and the switching unit. The transmission unit is configured to not transmit power from the electric motor to the switching unit when the electric motor rotates forward, and to transmit power from the electric motor to the switching unit when the electric motor rotates backward. According to the above configuration, the driving of the pump and the driving of the switching unit are performed by one electric motor. Thereby, the possibility of the pressure variable unit becoming large-sized is reduced.

[0370] (2) In the above pressure variable unit, it may also be that the switching unit includes: a plurality of valves respectively located between the plurality of connection targets and the pump; and a plurality of cams respectively opening and closing the plurality of valves. According to the above configuration, the connection between the plurality of connection targets and the pump can be switched with a relatively simple configuration.

[0371] (3) In the above pressure variable unit, it may also be that the switching unit includes a switching body located between the plurality of connection targets and the pump, and the connection between the plurality of connection targets and the pump is switched by rotation. According to the above configuration, the connection between the plurality of connection targets and the pump can be switched with a relatively simple configuration.

[0372] (4) In the above pressure variable unit, it may also be that the transmission unit includes a one-way clutch. According to the above configuration, power can be prevented from being transmitted from the electric motor to the switching unit when the electric motor rotates forward and power can be transmitted from the electric motor to the switching unit when the electric motor rotates backward with a relatively simple configuration.

[0373] (5) In the above-described pressure variable unit, it is also possible that the motor is a first motor, the pump is a first pump, the transmission unit is a first transmission unit, and the pressure variable unit includes: a second motor; a second pump connected to the second motor and driven by the power of the second motor; an atmosphere opening unit connected to a plurality of the connection targets and opening the plurality of connection targets to the atmosphere; and a second transmission unit located between the second motor and the atmosphere opening unit and transmitting the power of the second motor to the atmosphere opening unit. The second pump is configured to change the pressure of at least one of the plurality of connection targets, and the atmosphere opening unit is configured to close when the second motor rotates forward and open when the second motor rotates backward. According to the above configuration, the driving of the second pump and the opening and closing of the atmosphere opening unit are performed by one second motor. It is possible not only to change the pressure of the connection target by the first pump and the second pump, but also to restore the pressure of the connection target to atmospheric pressure by the atmosphere opening unit. In this way, it is possible to change the pressure of the connection target more freely.

[0374] (6) It is also possible that the above-described pressure variable unit includes: a detection unit that detects the rotation angle of the motor; and a control unit that controls the motor. The control unit performs opening control on the motor when rotating the motor forward and performs PID control on the motor based on the detection result of the detection unit when rotating the motor backward. According to the above configuration, by performing PID control on the motor, it is possible to switch the connection between a plurality of connection targets and the pump with high precision.

[0375] (7) A liquid ejection device includes: a liquid ejection unit that ejects liquid; and a liquid supply unit that supplies liquid to the liquid ejection unit. The liquid supply unit has: a supply flow path through which liquid flows toward the liquid ejection unit; and the above-described pressure variable unit. At least one of the liquid supply unit and the liquid ejection unit has a housing unit that houses liquid. The housing unit has a film member that divides the inside of the housing unit into an air chamber and a liquid chamber. The plurality of connection targets include the housing unit, and the pressure variable unit changes the pressure of the air chamber. According to the above configuration, by changing the pressure of the air chamber by the pressure variable unit, the pressure of the liquid chamber changes. For example, when the liquid chamber is pressurized, liquid is discharged from the liquid chamber. When the liquid chamber is depressurized, liquid flows into the liquid chamber. In this way, the pressure variable unit can control the flow of liquid by changing the pressure of the air chamber.

[0376] (8) In the above-described liquid ejection device, the housing portion may be one of a plurality of housing portions. Each of the plurality of housing portions has the air chamber. The plurality of housing portions are respectively provided in the liquid supply unit or the liquid ejection unit. The plurality of connection objects include the plurality of housing portions. The pressure variable unit selectively changes the pressures of the plurality of air chambers. According to the above configuration, the pressure variable unit can finely control the flow of the liquid.

[0377] (9) Alternatively, the above-described liquid ejection device may include: a frame that supports the pressure variable unit; and a fixing member that fixes the pressure variable unit to the frame. The fixing member is detachably attached to the pressure variable unit and the frame from above. According to the above configuration, by approaching the fixing member from above, the pressure variable unit can be easily detached from and attached to the frame.

[0378] (10) In the above-described liquid ejection device, the liquid supply unit may have an air flow path connected to the housing portion and the pump. The liquid ejection unit may include: an ejection portion that ejects the liquid; a moving body that mounts the ejection portion and is movable in the scanning direction; and a flow portion that is mounted on the moving body and is connected to the supply flow path and the ejection portion. The flow portion has the housing portion. The supply flow path has a first flexible member that deforms as the liquid ejection unit moves in the scanning direction. The air flow path has a second flexible member that deforms as the liquid ejection unit moves in the scanning direction. The upstream ends of the first flexible member and the second flexible member are located on one side with respect to the center of the moving region of the liquid ejection unit. According to the above configuration, the upstream ends of the first flexible member and the second flexible member are centrally arranged. The first flexible member and the second flexible member extend toward the flow portion. Therefore, the possibility that the lengths of the first flexible member and the second flexible member deviate significantly is reduced. By making the lengths of the first flexible member and the second flexible member close to each other, it is easy to align the first flexible member and the second flexible member. Thereby, the space occupied by the first flexible member and the second flexible member can be reduced.

[0379] (11) Alternatively, the above-described liquid ejection device may include a bundling body that bundles the first flexible member and the second flexible member. The bundling body has a holding portion that holds the first flexible member and a supporting portion that supports the second flexible member. The supporting portion has a pulley that contacts the second flexible member. According to the above configuration, the possibility that the second flexible member is damaged due to friction with the first flexible member and the bundling body is reduced.

[0380] (12)A bundling body bundles a plurality of flexible members connected to a unit that moves in the scanning direction. The plurality of flexible members include a first flexible member and a second flexible member. The bundling body includes: a holding portion that holds the first flexible member; and a supporting portion that movably supports the second flexible member. The supporting portion has a pulley that contacts the second flexible member. According to the above configuration, the second flexible member is supported by contacting the pulley. By rotating the pulley, the possibility of wear of the second flexible member is reduced. Since the first flexible member is held by the holding portion, there is no need to worry about wear of the first flexible member due to contact with the holding portion. Therefore, wear of the flexible members is reduced.

[0381] (13)In the above bundling body, it may be that the pulley has flanges at both axial ends. According to the above configuration, the possibility of the second flexible member contacting parts other than the pulley is reduced by the flanges.

[0382] (14)A liquid supply unit supplies liquid to a liquid ejection unit that ejects liquid, and includes: the above bundling body; and a plurality of the flexible members. The unit is the liquid ejection unit, and the first flexible member is a liquid pipe that supplies liquid to the liquid ejection unit. According to the above configuration, the bundling body can hold the liquid pipe.

[0383] (15)In the above liquid supply unit, it may be that the second flexible member is an air pipe that supplies air to the liquid ejection unit. According to the above configuration, the possibility of wear of the air pipe is reduced.

[0384] (16)A liquid supply unit supplies liquid to a liquid ejection unit that ejects liquid, and includes: the above bundling body; and a plurality of the flexible members. The unit is the liquid ejection unit, the first flexible member is a liquid pipe that supplies liquid to the liquid ejection unit, and the second flexible member is an air pipe that supplies air to the liquid ejection unit. According to the above configuration, the bundling body can hold the liquid pipe and can reduce the possibility of wear of the air pipe.

[0385] (17) In the above-described liquid supply unit, the liquid pipe may have: an extending portion that extends in the scanning direction; and a bending portion that bends into an arc shape from the extending portion toward the liquid ejection unit. The holding portion holds the extending portion, and the supporting portion supports the air pipe at a position closer to the liquid ejection unit than the holding portion. According to the above configuration, by supporting the air pipe at a position closer to the liquid ejection unit than the holding portion by the supporting portion, the curvature of the air pipe is made greater than the curvature of the liquid pipe. Compared with the liquid pipe, the air pipe can select a material with better bendability from the perspective of its barrier property. Therefore, even if the curvature of the air pipe is greater than the curvature of the liquid pipe, it does not matter. By supporting the air pipe at a position closer to the liquid ejection unit than the holding portion by the supporting portion, the space occupied by the air pipe and the liquid pipe can be reduced.

[0386] (18) The liquid ejection device includes the above-described liquid supply unit and the liquid ejection unit. According to the above configuration, wear of the flexible members can be reduced in the liquid ejection device.

[0387] (19) In the above-described liquid ejection device, the liquid ejection unit may have: an ejection portion that ejects liquid; a moving body that mounts the ejection portion and is movable in the scanning direction; and a flow portion that is mounted on the moving body and is connected to the first flexible member. The flow portion has a housing portion that houses liquid. The housing portion has a film member that divides the inside of the housing portion into a liquid chamber and an air chamber. The liquid supply unit has a pressure variable unit. The first flexible member communicates with the liquid chamber, and the second flexible member communicates with the air chamber. The pressure variable unit changes the pressure in the air chamber. According to the above configuration, when the pressure in the air chamber changes, the pressure in the liquid chamber changes. For example, when the liquid chamber is pressurized, liquid is discharged from the liquid chamber. When the liquid chamber is depressurized, liquid flows into the liquid chamber. Thus, by changing the pressure in the air chamber by the pressure variable unit, the flow of the liquid can be controlled.

[0388] (20) In the above-described liquid ejection device, the upstream ends of the first flexible member and the second flexible member may be located on one side with respect to the center of the moving region of the liquid ejection unit. According to the above configuration, the upstream ends of the first flexible member and the second flexible member are concentratedly arranged. The first flexible member and the second flexible member extend toward the flow portion. Therefore, the possibility that the length of the first flexible member deviates significantly from the length of the second flexible member is reduced. By making the length of the first flexible member close to the length of the second flexible member, it is easy to align the first flexible member and the second flexible member. Thereby, the space occupied by the first flexible member and the second flexible member can be reduced.

[0389] (21) A liquid ejection device includes: an ejection unit that ejects liquid from a nozzle; a housing unit connected to the ejection unit; a pressure variable unit connected to the housing unit; and a control unit that controls the pressure variable unit. The housing unit has a membrane component that divides the interior of the housing unit into an air chamber and a liquid chamber. The liquid chamber communicates with the ejection unit, and the air chamber communicates with the pressure variable unit. The pressure variable unit includes: a vacuum pump that decompresses the air chamber; and a motor that drives the vacuum pump. The control unit gradually increases the applied voltage of the motor until the applied voltage reaches a target voltage. According to the above configuration, since the air chamber is gradually decompressed, the possibility of liquid flowing rapidly from the ejection unit to the liquid chamber is reduced. Therefore, the possibility of air flowing into the ejection unit from the nozzle is reduced.

[0390] (22) In the above liquid ejection device, it may also be that the control unit starts increasing the applied voltage from a voltage smaller than the starting voltage of the motor. Generally, there is a deviation in the starting voltage of the motor. According to the above configuration, the possibility of the motor starting immediately after the applied voltage is first applied to the motor is reduced. Therefore, even when there is a deviation in the starting voltage of the motor, the possibility of the air chamber being rapidly decompressed is reduced.

[0391] (23) In the above liquid ejection device, it may also be that the control unit increases the applied voltage at a constant slope during a period from when the voltage is first applied to the motor until a specified time has elapsed. According to the above configuration, even when there is a deviation in the starting voltage of the motor, the possibility of the air chamber being rapidly decompressed is reduced.

[0392] (24) In the above liquid ejection device, it may also be that the control unit increases the slope of the applied voltage after the specified time has elapsed. According to the above configuration, compared with the case where the slope of the applied voltage remains constant, the time until the applied voltage reaches the target voltage is shortened.

[0393] (25) In the above liquid ejection device, it may also be that the control unit maintains the applied voltage at a relay voltage smaller than the target voltage for a certain period of time after increasing the slope of the applied voltage. When the slope of the applied voltage increases, the air chamber may be rapidly decompressed. In this case, air may flow into the ejection unit from the nozzle. Regarding this point, according to the above configuration, since the applied voltage is maintained at the relay voltage for a certain period of time, the possibility of the air chamber being rapidly decompressed is reduced.

[0394] (26) Alternatively, the above-described liquid ejection device may include: a moving body that mounts the ejection unit and is capable of moving; a supply flow path through which the liquid supplied to the ejection unit flows; and a flow unit that is mounted on the moving body and is connected to the supply flow path and the ejection unit, the flow unit having the accommodation unit. With the above configuration, the flow of the liquid supplied to the ejection unit can be controlled by the accommodation unit.

[0395] (27) Alternatively, the above-described liquid ejection device may include: a moving body that mounts the ejection unit and is capable of moving; a supply flow path through which the liquid supplied to the ejection unit flows; and a flow unit that is mounted on the moving body and is connected to the supply flow path and the ejection unit, the accommodation unit being located in the supply flow path. With the above configuration, the liquid in the ejection unit can be returned to the supply flow path.

[0396] (28) The above-described liquid ejection device may also be such that the flow unit has an adjustment valve located at a position upstream of the accommodation unit, the adjustment valve being configured to open when the pressure in the liquid chamber is equal to or lower than a specified pressure, the specified pressure being greater than the pressure resistance of the meniscus formed at the nozzle. With the above configuration, the adjustment valve opens before the pressure in the liquid chamber becomes lower than the pressure resistance of the meniscus. Therefore, the possibility of air flowing from the nozzle into the ejection unit is reduced.

[0397] (29) A control method for a liquid ejection device, the liquid ejection device including: an ejection unit that ejects liquid from a nozzle; a supply flow path through which the liquid supplied to the ejection unit flows; a flow unit that is connected to the supply flow path and the ejection unit and controls the flow of the liquid supplied to the ejection unit; a pressure variable unit that is connected to the flow unit; and a control unit that controls the pressure variable unit, the flow unit having: a membrane member that divides the flow space in the flow unit into an air chamber and a liquid chamber; and an adjustment valve located at a position upstream of the liquid chamber, the liquid chamber communicating with the ejection unit, the air chamber communicating with the pressure variable unit, the pressure variable unit including: a decompression pump that decompresses the air chamber; and a motor that drives the decompression pump, the adjustment valve being configured to open when the pressure in the liquid chamber is equal to or lower than a specified pressure, the control method for the liquid ejection device including: gradually increasing the applied voltage applied to the motor until the applied voltage reaches a target voltage. With the above method, the same effect as the above-described liquid ejection device can be obtained.

[0398] (30) The control method for the above-described liquid ejection device may also include: starting to increase the applied voltage from a voltage smaller than the starting voltage of the motor. With the above method, the same effect as the above-described liquid ejection device can be obtained.

Claims

1. A variable pressure unit, characterized in that: Change the pressure of multiple connected objects and have: Motor; A pump connected to the motor and driven by the power of the motor; a switching unit, using the power of the motor to switch the connection between the plurality of connection objects and the pump; as well as a transmission part, located between the motor and the switching part, The transmission unit is configured so that power is not transmitted from the motor to the switching unit when the motor rotates forward, and so that power is transmitted from the motor to the switching unit when the motor rotates reversely.

2. The variable pressure unit according to claim 1, characterized in that: The switching unit has: a plurality of valves, respectively located between the plurality of connection objects and the pump; and The plurality of cams respectively open and close the plurality of valves.

3. The variable pressure unit according to claim 1, characterized in that: The switching unit includes a switching body that is located between the plurality of connection objects and the pump and switches the connection between the plurality of connection objects and the pump by rotating.

4. The variable pressure unit according to claim 1, characterized in that: The transmission unit includes a one-way clutch.

5. The variable pressure unit according to claim 1, characterized in that: The motor is a first motor, The pump is a first pump, The transmission part is a first transmission part, The variable pressure unit comprises: Second motor; a second pump connected to the second motor and driven by the power of the second motor; An atmosphere opening portion connected to the plurality of connection objects to open the plurality of connection objects to the atmosphere; as well as a second transmission part, located between the second motor and the atmosphere open part, for transmitting power of the second motor to the atmosphere open part; The second pump is configured to change the pressure of at least one of the plurality of connection objects. The atmosphere opening portion is configured to be closed when the second motor rotates in the forward direction, and to be opened when the second motor rotates in the reverse direction.

6. The variable pressure unit according to any one of claims 1 to 5, characterized in that: The variable pressure unit comprises: a detection unit, detecting a rotation angle of the motor; and a control unit, controlling the motor, The control unit performs open control on the motor when rotating the motor in the forward direction, and performs PID control on the motor based on a detection result of the detection unit when rotating the motor in the reverse direction.

7. A liquid ejection device, characterized in that: have: a liquid ejecting unit that ejects liquid; and a liquid supply unit for supplying liquid to the liquid ejection unit; The liquid supply unit comprises: a supply flow path for liquid to flow toward the liquid ejection unit; as well as The pressure variable unit according to claim 1, At least one of the liquid supply unit and the liquid ejection unit has a container for containing liquid. The container has a membrane member that divides the interior of the container into an air chamber and a liquid chamber. A plurality of the connection objects include the receiving portion, The pressure variable unit changes the pressure of the air chamber.

8. The liquid ejection device according to claim 7, characterized in that: The receiving portion is one of a plurality of receiving portions, The plurality of accommodating parts respectively have the air chamber. The plurality of receiving portions are respectively arranged in the liquid supply unit or the liquid ejection unit. The plurality of connection objects include a plurality of the receiving portions, The pressure variable unit selectively changes the pressures of the plurality of air chambers.

9. The liquid ejection device according to claim 7, characterized in that: The liquid ejection device comprises: a frame supporting the variable pressure unit; and a fixing member, fixing the variable pressure unit to the frame, The fixing member is attached to and detached from the variable pressure unit and the frame from above.

10. The liquid ejection device according to claim 9, characterized in that: The liquid supply unit has an air flow path connected to the container and the pump. The liquid ejection unit comprises: a spraying portion for spraying the liquid; a movable body that carries the ejection unit and is movable in a scanning direction; and a flow unit mounted on the moving body and connected to the supply flow path and the ejection unit, The flow portion has the receiving portion, The supply flow path includes a first flexible member that is deformed as the liquid ejection unit moves in the scanning direction. The air flow path has a second flexible member that is deformed as the liquid ejection unit moves in the scanning direction. An upstream end of the first flexible member and an upstream end of the second flexible member are located on one side with respect to a center of a movement area of ​​the liquid ejection unit.

11. The liquid ejection device according to claim 10, characterized in that: The liquid ejection device includes a bundled body that bundles the first flexible member and the second flexible member. The bundling body includes a holding portion for holding the first flexible member and a supporting portion for supporting the second flexible member. The support portion has a pulley that contacts the second flexible member.

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