JP2016022696A - Liquid jet device and maintenance method of the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid jet device which efficiently solves clogging of nozzles of a liquid jet part, and to provide a maintenance method of the liquid jet device.SOLUTION: A printer includes: liquid jet heads 24A, 24B which jet an ink from openings of nozzles 46 to sheets; a steam jet device 74 including a steam generating part 76, which heats a liquid for steam generation and generates steam, and a steam jet part 82 capable of jetting the steam generated by the steam generating part 76. The stream jet device 74 jets the steam to the liquid jet heads 24A, 24B which are in an atmosphere having a temperature lower than a boiling point of the liquid for the steam generation and include the nozzles 46.SELECTED DRAWING: Figure 5

Description

  The present invention relates to a liquid ejecting apparatus such as an ink jet printer and a maintenance method for the liquid ejecting apparatus.

  Conventionally, as a kind of liquid ejecting apparatus, an ink jet printer that performs printing by ejecting ink from a nozzle of a recording head onto a medium such as paper has been known. In such a printer, when the nozzle of the inkjet head is clogged, so-called cleaning is performed in which the thickened ink or bubbles in the nozzle that cause clogging are sucked and removed.

  However, when ink that is particularly easy to solidify is used in the printer as described above, clogging of the nozzles may not be resolved even if the above-described cleaning is performed. Therefore, conventionally, an ink ejection device (liquid ejection device) provided with a cleaning device that dissolves and removes the solidified ink in the cleaning agent by ejecting the cleaning agent to the nozzle formation region of the inkjet head (liquid ejection unit). Has been proposed (see, for example, Patent Document 1).

JP 2002-178529 A

  By the way, in the cleaning device of the ink discharge apparatus as in Patent Document 1, the ink solidified in the cleaning agent is dissolved and removed by discharging the cleaning agent to the nozzle formation region of the inkjet head. That is, the cleaning agent is ejected in the form of a mist and applied to the nozzle and the periphery of the nozzle, and the cleaning agent is soaked and dissolved in the solidified ink. For this reason, it takes time for the cleaning agent to reach the solidified ink in the nozzle, and there is a problem that it is difficult to effectively eliminate clogging of the nozzle.

  The present invention has been made paying attention to such problems existing in the prior art. An object of the present invention is to provide a liquid ejecting apparatus and a maintenance method for the liquid ejecting apparatus that can efficiently eliminate clogging of nozzles of the liquid ejecting section.

Hereinafter, means for solving the above-described problems and the effects thereof will be described.
A liquid ejecting apparatus that solves the above problems includes a liquid ejecting unit that can eject a first liquid from a nozzle opening to a medium, a steam generating unit that generates steam by heating the second liquid, and the steam generating unit. A vapor injection device having a vapor injection unit capable of injecting the generated vapor, wherein the vapor injection device includes the nozzle in the atmosphere lower than the boiling point of the second liquid. On the other hand, the steam is injected.

  According to this configuration, the high-temperature vapor containing the second liquid droplets ejected from the vapor ejection unit enters the nozzle through the nozzle opening and permeates the clogged portion. It becomes possible to efficiently eliminate clogging.

  The liquid ejecting apparatus includes a cap capable of partitioning and forming a closed space including the nozzle opening of the liquid ejecting section in contact with the liquid ejecting section, and the vapor ejecting apparatus is partitioned by the cap It is preferable that the steam is injected into the closed space through an injection port provided in the cap.

  According to this configuration, since steam is injected from the injection port into the closed space in the cap, the nozzle is exposed to the steam in a state where the pressure in the closed space is high. Therefore, since it becomes easy for steam to enter the nozzle, clogging of the nozzle can be effectively eliminated.

  In the liquid ejecting apparatus, the cap is provided with an openable / closable exhaust port, and the ejector port provided in the cap is disposed in the closed space defined by the cap in a state where the exhaust port is closed. It is preferable to inject the steam through the valve and open the exhaust port when the pressure in the closed space exceeds a pressure setting value.

  According to this configuration, the steam is injected into the closed space by setting the pressure setting value so that the pressure of the closed space when the steam is injected into the closed space does not exceed the pressure value at which the first liquid in the nozzle solidifies. It is possible to suppress the first liquid in the nozzle from solidifying due to the pressure increase in the closed space.

  In the liquid ejecting apparatus, the cap is provided with an openable / closable exhaust port, and the ejector port provided in the cap is disposed in the closed space defined by the cap in a state where the exhaust port is closed. It is preferable that the steam is injected through the opening and the exhaust port is opened when the temperature of the closed space exceeds a temperature setting value.

  According to this configuration, the steam is injected into the closed space by setting the temperature setting value so that the temperature of the closed space when the steam is injected into the closed space does not exceed the temperature value at which the first liquid in the nozzle solidifies. It is possible to prevent the first liquid in the nozzle from solidifying due to the temperature rise in the closed space.

In the liquid ejecting apparatus, it is preferable that the second liquid is a liquid obtained by adding a preservative to pure water.
According to this configuration, it is possible to prevent the second liquid from being spoiled.

  A maintenance method for a liquid ejecting apparatus that solves the above problems includes a liquid ejecting unit that can eject a first liquid from a nozzle opening to a medium, a steam generating unit that heats a second liquid to generate steam, and the steam A liquid ejecting apparatus comprising: a vapor ejecting apparatus having a steam ejecting section capable of ejecting the steam generated by the generating section, wherein the steam is ejected to the liquid ejecting section including the nozzle After that, the first liquid is discharged from the opening of the nozzle.

  According to this configuration, unnecessary solidified first liquid or second liquid remaining in the nozzle that has been clogged by the vapor jet is discharged from the nozzle opening together with the first liquid in the liquid jet section. Therefore, the first liquid in the nozzle can be brought into a state where normal ejection can be performed.

  In the maintenance method for the liquid ejecting apparatus, the liquid ejecting apparatus includes a cap capable of partitioning and forming a closed space including the nozzle opening of the liquid ejecting section in contact with the liquid ejecting section. The steam is injected into the closed space through an injection port provided in the cap, and the pressure of the closed space is at least due to the injection of the steam while maintaining the state where the cap is in contact with the liquid injection unit. Preferably, the first liquid is discharged from the opening of the nozzle in a state where the pressure is higher than the atmospheric pressure, and the cap is separated from the liquid ejecting unit in a state where the pressure in the closed space is at least higher than the atmospheric pressure.

  According to this configuration, when the cap is separated from the liquid ejecting unit, it is possible to prevent air from being drawn into the nozzle from the nozzle opening. Therefore, the first liquid is poorly ejected due to the air being drawn into the nozzle. Can be suppressed.

  In the maintenance method of the liquid ejecting apparatus, it is preferable that the first liquid is discharged from the nozzle opening by pressurizing the first liquid in the liquid ejecting unit.

  According to this configuration, air is suppressed from being drawn into the nozzle from the nozzle opening after the first liquid is discharged from the nozzle opening, so that the first liquid caused by the air being drawn into the nozzle can be prevented. It is possible to suppress the occurrence of injection failure.

1 is a schematic side view of a printer according to an embodiment. FIG. 3 is a schematic cross-sectional view of a liquid ejecting head. FIG. 3 is a schematic plan view showing a printing unit and maintenance units arranged in a non-printing area. FIG. 2 is a schematic plan view showing a detailed configuration of a printing unit and maintenance units arranged in a non-printing area. The cross-sectional schematic diagram which shows the connection structure of the cap for steam injection, and a steam injection apparatus. FIG. 3 is a block diagram illustrating an electrical configuration of the printer.

Hereinafter, as an example of a liquid ejecting apparatus, an embodiment of an ink jet printer that ejects ink and prints an image including characters and figures will be described with reference to the drawings.
As shown in FIG. 1, the printer 11 includes a transport unit 13 that transports a sheet ST as an example of a medium supported by the support base 12 in the transport direction Y along the surface of the support base 12, and the transported sheet ST. In addition, a printing unit 20 that performs printing by ejecting ink as an example of the first liquid, and a heating unit 17 and a blowing unit 18 for drying the ink that has landed on the sheet ST are provided.

  The support 12, the transport unit 13, the heat generating unit 17, the air blowing unit 18, and the printing unit 20 are assembled in a printer main body 11 a that includes a housing, a frame, and the like. The support 12 is provided in the printer 11 so as to extend in the width direction of the sheet ST (a direction orthogonal to the paper surface in FIG. 1).

  The conveyance unit 13 includes a conveyance roller pair 14a and a conveyance roller pair 14b that are respectively arranged on the upstream side and the downstream side of the support base 12 in the conveyance direction Y and are driven by a conveyance motor 49 (see FIG. 6). Further, the transport unit 13 includes a guide plate 15a and a guide plate 15b that are arranged on the upstream side and the downstream side of the transport roller pair 14a and the transport roller pair 14b in the transport direction Y and guide the sheet ST while supporting it. .

  Then, the conveyance unit 13 conveys the sheet ST along the surface of the support base 12 and the surfaces of the guide plates 15a and 15b by the conveyance roller pair 14a and 14b rotating while sandwiching the sheet ST. In the present embodiment, the sheet ST is continuously conveyed by being fed out from the roll sheet RS wound around the supply reel 16a in a roll shape. Then, the sheet ST that is fed out from the roll sheet RS and continuously conveyed is printed on the roll by the take-up reel 16b again after the printing unit 20 has the ink attached thereto to print an image.

  The printing unit 20 is guided by guide shafts 21 and 22 extending along a scanning direction X that is a width direction of the sheet ST orthogonal to the transport direction Y of the sheet ST, and the carriage motor 48 (see FIG. 6). A carriage 23 that can reciprocate in the scanning direction X by power is provided. The carriage 23 includes two liquid ejecting heads 24A and 24B as an example of a liquid ejecting section that ejects ink, a storage section 30 that stores ink to be supplied to the liquid ejecting heads 24A and 24B, and a flow path to the storage section 30. A connection tube 27 that supplies ink via an adapter 28 is attached. The reservoir 30 is held by a reservoir holder 25 attached to the carriage 23.

  As shown in FIGS. 1 and 2, the storage unit 30 includes a differential pressure valve 31 provided in the middle of the first ink supply path 32 for supplying internal ink to the liquid ejecting heads 24 </ b> A and 24 </ b> B. . The differential pressure valve 31 is opened when the pressure of the ink on the downstream side becomes a predetermined negative pressure with respect to the atmospheric pressure as the ink is ejected (consumed) by the liquid ejecting heads 24A and 24B located on the downstream side thereof. When ink is supplied from the reservoir 30 to the liquid ejecting heads 24A and 24B by opening the valve and the negative pressure on the downstream side is eliminated, the valve is closed.

  As shown in FIG. 2, the liquid ejecting heads 24 </ b> A and 24 </ b> B include a cylindrical main body case 33. A second ink supply path 34 that penetrates the main body case 33 in the vertical direction Z is formed at a position near the one end portion in the scanning direction X in the main body case 33, and a fixed plate 35 is located at a position near the other end portion in the scanning direction X. Is erected. The downstream end of the first ink supply path 32 is connected to the upstream end of the second ink supply path 34.

  An elastic rectangular thin plate-shaped diaphragm 36 is fixed to the lower surface of the main body case 33 so as to cover the lower end opening of the main body case 33 and the lower end opening of the second ink supply path 34. In the main body case 33, one side surface at the upper end of the piezoelectric element 37 is fixed to the fixed plate 35, and the lower surface of the piezoelectric element 37 is fixed to the upper surface of the vibration plate 36.

  On the lower side of the piezoelectric element 37, a plurality of notch grooves (not shown) extending across the entire width in the scanning direction X of the piezoelectric element 37 are provided at intervals in the transport direction Y. The depth of each notch groove (not shown) is set to about half the height of the piezoelectric element 37 in the vertical direction Z. A portion sandwiched between the notch grooves (not shown) in the piezoelectric element 37 is a piezoelectric element portion 37a. Grooves 38 are formed in a lattice shape on the upper surface of the vibration plate 36 so as to surround each piezoelectric element portion 37 a, and an eye portion of the lattice-shaped groove 38 in the vibration plate 36 is an island portion 39.

  A flow path forming plate 40 having a rectangular frame shape is fixed in close contact with the lower surface of the vibration plate 36, and a rectangular plate shaped nozzle plate 41 is fixed in close contact with the lower surface of the flow path forming plate 40. An ink storage chamber 42 is formed near the one end in the scanning direction X between the vibration plate 36 and the nozzle plate 41. The ink storage chamber 42 communicates with the second ink supply path 34 through a communication hole 43 formed in the vibration plate 36. The ink storage chamber 42 temporarily stores ink supplied from the storage unit 30 via the second ink supply path 34.

  At a position near the other end in the scanning direction X between the vibration plate 36 and the nozzle plate 41, a pressure chamber 44 corresponding to each piezoelectric element portion 37a in the vertical direction Z is formed. Between the ink storage chamber 42 and the pressure chambers 44 between the vibration plate 36 and the nozzle plate 41, communication paths 45 that connect the ink storage chambers 42 and the pressure chambers 44 are respectively formed.

  Therefore, the ink temporarily stored in the ink storage chamber 42 is supplied to each pressure chamber 44 via each communication path 45. Nozzles 46 are respectively provided at positions corresponding to the pressure chambers 44 in the nozzle plate 41, and the lower surface of the nozzle plate 41 is a nozzle forming surface 24a in which the nozzles 46 are opened. Each nozzle 46 communicates with each pressure chamber 44.

  One end of a strip-like flexible circuit board 47 is connected to the side surface of the upper end of the piezoelectric element 37 opposite to the fixed plate 35 side, and the other end of the flexible circuit board 47 is connected to a controller 94 (see FIG. 6). The piezoelectric elements 37 are individually expanded and contracted along the vertical direction Z by the drive signals generated by the control unit 94 (see FIG. 6) being input via the flexible circuit board 47. Drive) is possible.

  Then, the island portions 39 of the diaphragm 36 vibrate based on the expansion and contraction movement of the piezoelectric element portions 37a, whereby the pressure in each pressure chamber 44 is changed, and each pressure chamber is changed by the pressure change in each pressure chamber 44. The ink in the nozzle 44 is ejected from the opening of each nozzle 46. The piezoelectric element 37 is in a state where each piezoelectric element portion 37a is displaced (contracted) in a direction in which a voltage is applied to the piezoelectric element 37 and the diaphragm 36 is elastically deformed to increase the volume of each pressure chamber 44. The pressure chambers 44 can be pressurized by stopping the application of voltage to the piezoelectric element 37 and bringing the diaphragm 36 into a state before elastic deformation.

  As shown in FIGS. 1 and 2, the liquid ejecting heads 24 </ b> A and 24 </ b> B are attached to the lower end portion of the carriage 23 with the nozzle forming surface 24 a facing the support base 12 at a predetermined interval in the vertical direction Z. . On the other hand, the storage unit 30 is attached to the upper side that is opposite to the liquid jet heads 24 </ b> A and 24 </ b> B in the vertical direction Z with respect to the carriage 23. In addition, the downstream end of the connection tube 27 is connected to the flow path adapter 28 at a position above the reservoir 30.

  The upstream end portion of the connection tube 27 is connected to the downstream end portions of the plurality of ink supply tubes 26 that can be deformed following the reciprocating carriage 23 and the connection portion 26 a attached to a part of the carriage 23. It is connected. In this embodiment, ink from an ink tank (not shown) containing ink passes through the ink supply tube 26, the connection tube 27, and the flow path adapter 28 by driving the pressure pump 96 (see FIG. 6). It is supplied to the storage unit 30.

  In the printing unit 20, ink is ejected from the openings of the plurality of nozzles 46 of the liquid ejecting heads 24 </ b> A and 24 </ b> B to the sheet ST on the support base 12 in the process in which the carriage 23 moves (reciprocates) in the scanning direction X. The heat generating portion 17 for heating and drying the ink that has landed on the sheet ST is disposed at an upper position in the printer 11 with a predetermined length interval from the support base 12 in the vertical direction Z. The printing unit 20 can reciprocate between the heat generating unit 17 and the support base 12 along the scanning direction X.

  The heat generating portion 17 includes a heat generating member 17a such as an infrared heater and a reflecting plate 17b extending along the same scanning direction X as the extending direction of the support base 12, and is in an area indicated by a one-dot chain line arrow in FIG. The ink adhering to the sheet ST is heated by radiated heat such as infrared rays (for example, radiant heat). In addition, the air blowing unit 18 that dries the ink attached to the sheet ST by the air blowing is disposed at an upper position that is spaced from the support base 12 so that the printing unit 20 can reciprocate in the printer 11.

  A heat shield member 29 that blocks heat transfer from the heat generating portion 17 is provided at a position between the storage portion 30 and the heat generating portion 17 in the carriage 23. The heat shielding member 29 is made of a metal material having good thermal conductivity such as stainless steel or aluminum, and covers at least the upper surface portion of the storage portion 30 facing the heat generating portion 17.

  In the printer 11, the storage unit 30 is provided for each ink type. The printer 11 according to the present embodiment includes a storage unit 30 that stores colored ink, and can perform color printing and monochrome printing. For example, the ink colors of the colored ink are cyan, magenta, yellow, black, and white. Each colored ink contains a preservative.

  The white ink is used for, for example, base printing (solid printing (filled printing)) before color printing when the sheet ST is a transparent or translucent film or a dark medium. The Of course, the color ink to be used can be arbitrarily selected, and may be, for example, three colors of cyan, magenta, and yellow. In addition to the above three colors, at least one color among light cyan, light magenta, light yellow, orange, green, gray, and the like can be further added to the colored ink.

  As shown in FIG. 3, ink droplets ejected from the openings of the nozzles 46 (see FIG. 2) of the liquid ejecting heads 24 </ b> A and 24 </ b> B are landed on the maximum width sheet ST conveyed on the support base 12. The area of the maximum width in the possible scanning direction X is a print area PA. That is, the ink droplets ejected from the openings of the nozzles 46 (see FIG. 2) of the liquid ejecting heads 24A and 24B to the sheet ST land in the printing area PA.

  In a non-printing area NA that is an area where the liquid ejecting heads 24A and 24B movable in the scanning direction X do not face the sheet ST being conveyed, a wiper unit 50, a flushing unit 51, a cap unit 52, and a vapor ejecting apparatus 74 is provided. When the printing unit 20 has a borderless printing function, the printing area PA is slightly wider in the scanning direction X than the range of the maximum width sheet ST to be conveyed.

  The wiper unit 50 has a wiper 50a for wiping the nozzle forming surface 24a (see FIG. 1). The wiper 50 a of this embodiment is movable and performs a wiping operation with the power of the wiping motor 53. The flushing unit 51 includes a liquid receiving portion 51a that receives ink droplets ejected from the openings of the nozzles 46 (see FIG. 2) of the liquid ejecting heads 24A and 24B.

  The liquid receiving portion 51a of the present embodiment is constituted by a belt, and moves the belt by the power of the flushing motor 54 at a predetermined time when it can be considered that the amount of ink stain on the belt due to flushing exceeds a specified amount. Note that flushing is an operation for forcibly ejecting (discharging) ink droplets from all the nozzles 46 irrespective of printing for the purpose of preventing and eliminating clogging of the nozzles 46 (see FIG. 2).

  The cap unit 52 has two cap portions 52a that can contact the nozzle forming surfaces 24a (see FIG. 1) of the two liquid jet heads 24A and 24B so as to surround the openings of the nozzles 46. The two cap portions 52a are configured to be movable between a contact position that contacts the nozzle forming surface 24a and a retracted position away from the nozzle forming surface 24a by the power of the capping motor 55. The positions at which the liquid ejecting heads 24A and 24B are capped by the corresponding cap portions 52a are the home positions HP of the liquid ejecting heads 24A and 24B (or the carriage 23).

  As shown in FIG. 4, the two liquid jet heads 24A and 24B attached to the lower end portion of the carriage 23 are arranged so as to be separated by a predetermined distance in the scanning direction X and shifted by a predetermined distance in the transport direction Y. ing. On the nozzle formation surface 24a of the liquid ejecting heads 24A and 24B, a total of eight nozzle rows 24b in which two rows located close to each other are arranged at regular intervals in the scanning direction X are formed.

  The eight nozzle rows 24b formed on the nozzle forming surface 24a are each composed of a large number (for example, 180) of nozzles 46 formed at a constant nozzle pitch in the transport direction Y. The two liquid ejecting heads 24A and 24B have the same nozzle pitch between the nozzles 46 at the ends of the two liquid ejecting heads 24A and 24B when the plurality of nozzles 46 constituting the nozzle row 24b are projected in the scanning direction X. The positional relationship in the transporting direction Y is possible.

  The wiper unit 50 includes a movable housing 59 that can reciprocate on a pair of rails 58 extending in the transport direction Y by the power of the wiping motor 53. In the housing 59, a feeding shaft 60 and a winding shaft 61 that are positioned at a predetermined distance in the wiping direction (same as the transport direction Y) are rotatably supported. A feeding roll 63 around which an unused cloth sheet 62 is wound is mounted on the feeding shaft 60, and a winding roll 64 on which a used cloth sheet 62 is wound is mounted on the winding shaft 61.

  The cloth sheet 62 hung between the feeding roll 63 and the take-up roll 64 is wound around the upper surface of the pressing roller 65 in a state of partially protruding upward from an opening (not shown) at the center of the upper surface of the housing 59, A semi-cylindrical (convex) wiper 50 a is formed at a portion wound around the pressing roller 65. The wiper 50a is biased upward.

  The casing 59 is a wiping direction through a cassette that houses the feeding roll 63 and the take-up roll 64, and a power transmission mechanism (for example, a rack and pinion mechanism) that is guided by the rail 58 and that is not illustrated by the power of the wiping motor 53. It is comprised from the holder which can reciprocately move (same in the conveyance direction Y). The housing 59 is driven in the transport direction Y between the retracted position shown in FIG. 4 and the wiping position at which the wiper 50a finishes wiping the nozzle forming surface 24a when the wiping motor 53 is driven forward and backward. Move back and forth.

  At this time, when the forward movement of the housing 59 is finished, the power transmission mechanism is switched to a state in which the wiping motor 53 and the winding shaft 61 are connected so as to be able to transmit power, and the power when the wiping motor 53 is driven in reverse rotation is switched. A backward movement operation of the housing 59 and a predetermined amount of winding operation of the cloth sheet 62 around the winding roll 64 are performed. The two liquid ejecting heads 24A and 24B are sequentially moved with respect to the wiping area WA, and the wiping of each of the two liquid ejecting heads 24A and 24B by the reciprocating movement of the housing 59 with respect to the nozzle forming surface 24a is performed in the wiping area WA. Each moved one is done individually.

  The flushing unit 51 includes a driving roller 66 and a driven roller 67 that are parallel to each other in the transport direction Y, and an endless belt 68 that is wound between the driving roller 66 and the driven roller 67. The belt 68 has a width equal to or greater than eight (2 × 4) nozzle rows 24b in the scanning direction X, and receives the ink ejected from the nozzles 46 of the liquid ejecting heads 24A and 24B. The liquid receiving portion 51a is configured. In this case, the outer peripheral surface of the belt 68 is a liquid receiving surface 69 that receives ink.

  The flushing unit 51 has a moisturizing liquid supply unit (not shown) capable of supplying a moisturizing liquid to the liquid receiving surface 69 below the belt 68 and a liquid that scrapes off waste ink and the like adhering to the liquid receiving surface 69 in a moisturizing state. The waste ink received by the liquid receiving surface 69 is removed from the belt 68 by the liquid scraping portion. Therefore, the receiving range of the liquid receiving surface 69 facing the nozzle forming surface 24a is updated by the circular movement of the belt 68.

  The cap unit 52 has two cap portions 52a that can be in contact with the nozzle forming surfaces 24a of the two liquid ejecting heads 24A and 24B to form a sealed space. As described above, each cap portion 52a moves between a contact position where it can contact the nozzle forming surface 24a and a retracted position away from the nozzle forming surface 24a by the power of the capping motor 55. Each cap 52a includes one suction cap 70, one vapor jet cap 75 as an example of a cap, and four moisturizing caps 71.

  Each of the moisturizing caps 71 is in contact with the nozzle forming surface 24a to form a closed space that surrounds the two nozzle rows 24b, and moisturizes the closed space. Specifically, the ink in the nozzle 46 that opens into the moisturizing cap 71 due to evaporation of water in the dispersion medium or solvent (for example, water) included in the waste ink remaining in the moisturizing cap 71 or the moisturizing liquid. Is moisturized.

  The suction cap 70 is connected to a suction pump 73 via a tube 72. Then, by driving the suction pump 73 in a state where the suction cap 70 is in contact with the nozzle forming surface 24a to form a sealed space, the ink 46 can be increased in viscosity from the nozzle 46 due to the negative pressure acting in the suction cap 70. So-called suction cleaning is performed in which bubbles or the like are sucked and discharged together with ink.

  Such suction cleaning is performed on the liquid jet heads 24A and 24B by two nozzle rows 24b. After the completion of the suction cleaning, wiping for removing ink adhering to the nozzle forming surface 24a and flushing for adjusting the ink meniscus in the nozzle 46 are sequentially performed.

  As shown in FIG. 4, the moving area in which the liquid ejecting heads 24A and 24B can move in the scanning direction X includes a printing area PA in which ink can be landed from the nozzles 46 of the liquid ejecting heads 24A and 24B when the sheet ST is printed, Other non-printing areas NA are included. The non-printing area NA includes a wiping area WA in which the wiper unit 50 is provided, a receiving area FA in which the flushing unit 51 is provided, and a maintenance area MA in which the cap unit 52 is provided.

  That is, in the non-printing area NA, the wiping area WA, the receiving area FA, and the maintenance area MA are arranged in the order of the wiping area WA, the receiving area FA, and the maintenance area MA from the printing area PA side in the scanning direction X. Yes. Further, in a region corresponding to the print region PA in the scanning direction X, a heating region HA provided with a heat generating portion 17 for fixing the ink landed on the sheet ST by heating is disposed.

  As shown in FIGS. 3 and 5, the steam injection device 74 is disposed adjacent to the cap unit 52 in the scanning direction X in the non-printing area NA. That is, in the scanning direction X, the vapor injection device 74 is disposed so as to face the flushing unit 51 with the cap unit 52 interposed therebetween.

  As shown in FIG. 5, the vapor ejecting device 74 is a vapor generating liquid that is a liquid (second liquid) obtained by adding a preservative to the same pure water as the main solvent of the ink to be used (pure water in this embodiment). The steam generation part 76 which heats and produces | generates a vapor | steam is provided. The steam generation unit 76 includes a case 77 having a substantially rectangular parallelepiped shape made of a metal material having good thermal conductivity such as stainless steel. Note that the preservative contained in the liquid for generating steam (second liquid) is preferably the same as the preservative contained in the ink, for example, an aromatic halogen compound (eg, Preventol CMK), methylene dithiocyanate. Nert, halogen-containing nitrogen-sulfur compound, 1,2-benzisothiazolin-3-one (for example, PROXEL GXL) and the like.

  A vapor generation liquid is accommodated inside the case 77. The preservative contained in the vapor generating liquid is preferably the same as the preservative contained in the ink. A heater 78 that heats the case 77 and a thermostat 80 that suppresses an excessive increase in the temperature of the case 77 are attached to the lower surface of the case 77. The thermistor 79 for detecting the temperature of the heater 78 is attached to the heater 78.

  An air release pipe 81 that opens the inside of the case 77 to the atmosphere is provided on one end side of the upper surface of the case 77, and a cylindrical steam injection unit 82 that can inject steam generated in the case 77 to the outside on the other end side. Is provided. The atmosphere release pipe 81 is provided with a safety valve 83 that is normally closed. When the pressure in the case 77 rises excessively, the safety valve 83 is opened and the case 77 is opened to the atmosphere.

  The vapor jet cap 75 has a bottomed rectangular box shape with the upper end opened, and the openings (nozzle rows 24b) of the plurality of nozzles 46 are brought into contact with the nozzle formation surface 24a of the liquid jet heads 24A and 24B. A closed space HK is formed. That is, when the vapor jet cap 75 abuts on the nozzle formation surface 24a of the liquid jet heads 24A and 24B, the vapor formation cap 75 defines a closed space HK with the nozzle formation surface 24a.

  In the steam injection cap 75, a temperature sensor 84 for detecting the temperature of the closed space HK and a pressure sensor 85 for detecting the pressure of the closed space HK are provided. An injection port 86 is formed on one end side of the bottom wall of the steam injection cap 75 so as to penetrate therethrough, and an exhaust port 87 is formed on the other end side thereof. The exhaust port 87 is provided with a first electromagnetic valve 88 for opening and closing the exhaust port 87.

  On the bottom surface of the steam injection cap 75, a cylindrical injection convex portion 89 communicating with the injection port 86 and a cylindrical exhaust convex portion 90 communicating with the exhaust port 87 are projected. One end of the exhaust tube 91 is connected to the exhaust projection 90, and the other end of the exhaust tube 91 is open. One end side of the steam supply tube 92 is connected to the ejection convex portion 89, and the other end side of the steam supply tube 92 is connected to the steam ejection portion 82. Therefore, the ejection projection 89 and the steam ejection part 82 communicate with each other via the steam supply tube 92. A second electromagnetic valve 93 that opens and closes the steam supply tube 92 is provided in the middle of the steam supply tube 92.

Next, the electrical configuration of the printer 11 will be described.
As shown in FIG. 6, the printer 11 includes a control unit 94 that controls the printer 11 in an integrated manner. The control unit 94 is electrically connected to the linear encoder 95. The linear encoder 95 has a tape-shaped code plate provided on the back side of the carriage 23 so as to extend along the guide shaft 22, and a fixed pitch that is fixed to the carriage 23 (see FIG. 1) and perforated in the code plate. And a sensor for detecting light transmitted through the slit.

  The control unit 94 inputs a number of pulses proportional to the amount of movement of the printing unit 20 (see FIG. 1) from the linear encoder 95, and the printing unit 20 sets the number of pulses input to the home position HP (see FIG. 3). The position of the printing unit 20 in the scanning direction X is grasped by adding the value when moving away from the position and subtracting the value when approaching the home position HP.

  The controller 94 is electrically connected to the piezoelectric element 37 via the driving circuit 100 and controls the driving of the piezoelectric element 37. The control unit 94 grasps clogging of each nozzle 46 based on the period of residual vibration of each island portion 39 of the diaphragm 36 by driving the piezoelectric element 37 (each piezoelectric element portion 37a).

  The control unit 94 is electrically connected to the carriage motor 48, the transport motor 49, the wiping motor 53, the flushing motor 54, and the capping motor 55 via the motor drive circuits 101 to 105, respectively. The control unit 94 controls driving of the motors 48, 49, 53, 54, and 55, respectively.

  The controller 94 is electrically connected to the suction pump 73 and the pressurization pump 96 via the pump drive circuits 106 and 107, respectively. And the control part 94 drive-controls the pumps 73 and 96, respectively. The controller 94 is electrically connected to the first electromagnetic valve 88 and the second electromagnetic valve 93 via valve drive circuits 108 and 109, respectively. And the control part 94 drive-controls the solenoid valves 88 and 93, respectively.

  The controller 94 is electrically connected to the heater 78 via the heater drive circuit 110 and the thermostat 80. The control unit 94 performs energization control of the heater 78 based on a signal transmitted from the thermistor 79. The thermostat 80 cuts off the energization to the heater 78 when the temperature of the case 77 exceeds a predetermined value, and allows the energization to the heater 78 when the temperature of the case 77 becomes the predetermined value or less. The temperature of the case 77 is prevented from rising excessively.

  The control unit 94 is electrically connected to the temperature sensor 84 and the pressure sensor 85, respectively. The controller 94 stores a temperature set value and a pressure set value. And the control part 94 drive-controls the 1st solenoid valve 88 based on the signal, temperature setting value, and pressure setting value which are each transmitted from the temperature sensor 84 and the pressure sensor 85. FIG. That is, the controller 94 satisfies at least one of the condition that the temperature detected by the temperature sensor 84 exceeds the temperature set value and the condition that the pressure detected by the pressure sensor 85 exceeds the pressure set value. If this happens, the first electromagnetic valve 88 is opened.

  On the other hand, the control unit 94 satisfies both the condition that the temperature detected by the temperature sensor 84 is equal to or lower than the temperature set value and the condition that the pressure detected by the pressure sensor 85 is equal to or lower than the pressure set value. If it is, the first electromagnetic valve 88 is closed. The temperature set value and the pressure set value are preferably set to values slightly lower than the upper limit values at which the ink in the nozzles 46 does not solidify (does not adversely affect the ink in the nozzles 46).

Next, the operation of the printer 11 will be described.
When print data is input from an external device to the control unit 94, the control unit 94 drives the carriage motor 48 based on the print data, and the liquid ejecting heads 24A and 24B move while the printing unit 20 moves in the scanning direction X. Ink droplets are ejected from the nozzles 46 toward the surface of the sheet ST. Then, the ejected ink droplets land on the surface of the sheet ST, so that an image or the like is printed on the surface of the sheet ST.

  By the way, during the printing of the sheet ST, for the purpose of preventing thickening of ink in the nozzles 46 that do not eject ink droplets among all the nozzles 46, every predetermined time (for example, within a range of 10 to 30 seconds). ), The printing unit 20 moves to the receiving area FA, and performs flushing for ejecting and discharging ink droplets from all the nozzles 46.

  When a predetermined cleaning condition is satisfied, the control unit 94 controls the carriage motor 48 to move the printing unit 20 to the home position HP and perform suction cleaning. In the suction cleaning, the suction pump 73 is driven to apply a negative pressure to the suction cap 70 in a state where the suction cap 70 is brought into contact with the nozzle forming surface 24a so as to surround the nozzle row 24b to form a sealed space. Thus, a predetermined amount of ink is sucked from each nozzle 46 to remove thickened ink, bubbles, and the like. After the suction cleaning is completed, the control unit 94 moves the printing unit 20 to the wiping area WA, wipes the nozzle forming surface 24a with the wiper 50a, and then moves the printing unit 20 to the receiving area FA to the liquid receiving unit 51a. Flush toward.

  Thereafter, the control unit 94 detects clogging of each nozzle 46 based on the period of residual vibration of each island portion 39 of the diaphragm 36 by driving the piezoelectric element 37 (each piezoelectric element portion 37a). Here, the clogging of each nozzle 46 is detected after completion of the suction cleaning, in particular, resin ink containing a synthetic resin that is cured by heating or UV ink that is cured by UV (ultraviolet) irradiation. This is because, when used, the nozzle 46 may not be clogged even if suction cleaning is performed. Here, the clogging is not only the state in which the ink in the nozzle 46 is solidified and clogged, but also the ink in the nozzle 46, the pressure chamber 44, and the communication passage 45 is thickened to increase the viscosity of the nozzle 46. Including the state where ink cannot be ejected (ejected) normally.

  If the clogging of all the nozzles 46 is not detected and the print job is waiting, the control unit 94 moves the printing unit 20 to the printing area PA and prints the sheet ST. On the other hand, when the clogged nozzle 46 is detected among all the nozzles 46, the control unit 94 moves the printing unit 20 to the non-printing area NA on the home position HP side in the scanning direction X, and clogs. The nozzle 46 is clogged by injecting the steam from the steam injection device 74 to the nozzle 46.

  When the clogging of the clogged nozzle 46 is eliminated by the vapor injection device 74, first, the nozzle row 24b including the clogged nozzle 46 and the vapor injection cap 75 are in the vertical direction Z. The printing unit 20 is moved so as to face each other. Subsequently, the cap portion 52a is raised so as to contact the nozzle forming surface 24a in a state of surrounding the nozzle row 24b including the nozzle 46 in which the vapor injection cap 75 is clogged. At this time, the liquid jet heads 24A and 24B including the nozzle 46 are in an atmosphere having a temperature lower than the boiling point (about 100 ° C.) of the vapor generation liquid.

  As shown in FIG. 5, when the heater 78 is energized, the case 77 is heated by the heat of the heater 78 and the vapor generating liquid in the case 77 is heated. When the steam generating liquid boils in the case 77 and generates steam, the generated steam flows from the steam injection portion 82 into the steam supply tube 92 outside the case 77. The pressure in the case 77 at this time is about 300 kPa in this embodiment.

  The heating temperature of the steam generating liquid is higher than the boiling point of the main solvent (pure water in this embodiment) of the steam generating liquid, and other components (preservatives in this embodiment) contained in the steam generating liquid. It is preferably lower than the boiling point. By setting the heating temperature in this way, components other than the main solvent are not included in the generated vapor, so that when the vapor generating liquid is mixed with the ink in the nozzle 46, the vapor generating liquid is transferred to the ink. It is possible to suppress adverse effects.

  When the second solenoid valve 93 is opened while the first solenoid valve 88 is closed, the steam that has flowed from the steam injection section 82 into the steam supply tube 92 flows through the injection projection 89. The fuel is ejected from the ejection port 86 into the closed space HK (in the vapor ejection cap 75), and is then ejected to the liquid ejection heads 24A and 24B including the nozzle 46. In this embodiment, the steam is injected into the closed space HK at this time for about 5 seconds.

  Then, the closed space HK is filled with steam, the pressure of the closed space HK increases, and the nozzle 46 is exposed to the steam in a state where the pressure of the closed space HK is high. The pressure of the closed space HK at this time is preferably 20 to 70 kPa in consideration of the influence on the ink in the nozzle 46. Furthermore, at this time, if the temperature of the closed space HK abnormally increases and exceeds the temperature set value, or if the pressure of the closed space HK abnormally increases and exceeds the pressure set value, the first electromagnetic valve 88 is The valve is opened and the temperature or pressure of the closed space HK is lowered.

  And since the high-temperature vapor | steam with which the closed space HK was filled contains the droplet of the liquid for vapor | steam generation | occurrence | production, it solidified which entered the nozzle 46 from the opening of the nozzle 46, and is the cause of clogging in the nozzle 46 The ink penetrates into the ink or between the solidified ink and the nozzle 46. As a result, the adhesive force of the solidified ink in the nozzle 46 is rapidly reduced, the solidified ink is quickly removed, and the clogging of the nozzle 46 is effectively eliminated.

  Subsequently, the cap portion 52a is lowered to separate the vapor jet cap 75 from the nozzle forming surface 24a. Subsequently, the printing unit 20 is moved so that the nozzle row 24 b including the nozzle 46 to which the steam is applied and the suction cap 70 face each other in the vertical direction Z. Subsequently, the cap portion 52a is raised so that the suction cap 70 is in contact with the nozzle forming surface 24a in a state of surrounding the nozzle row 24b including the nozzle 46 to which steam is applied.

  Subsequently, the suction pump 73 is driven to apply a negative pressure in the suction cap 70, whereby a predetermined amount of ink is sucked from each nozzle 46 and remains in each nozzle 46. The ink is discharged into the suction cap 70 together with the ink to perform suction cleaning. After the suction cleaning is completed, the control unit 94 moves the printing unit 20 to the wiping area WA, wipes the nozzle forming surface 24a with the wiper 50a, and then moves the printing unit 20 to the receiving area FA to the liquid receiving unit 51a. Flush toward.

As described above, according to the embodiment described in detail, the following effects can be obtained.
(1) The vapor of the vapor generating liquid is ejected to the liquid ejecting heads 24A and 24B including the nozzle 46 in the atmosphere lower than the boiling point of the vapor generating liquid. That is, by injecting the steam generated by the steam injection device 74 from the injection port 86 into the closed space HK partitioned by the steam injection cap 75, the liquid jet head is applied to the steam in a state where the pressure of the closed space HK is high. The nozzles 24A and 24B are exposed. For this reason, a high-temperature vapor containing droplets of the liquid for vapor generation ejected from the ejection port 86 into the closed space HK enters the nozzle 46 from the opening of the nozzle 46 and is clogged (in the solidified ink or the It penetrates between the solidified ink and the nozzle 46. Therefore, the adhesion of the solidified ink to the nozzle 46 is reduced and the solidified ink can be easily removed, so that the clogging of the nozzle 46 can be effectively eliminated.

  (2) The steam injection cap 75 is provided with an openable / closable exhaust port 87, and the steam generation liquid is supplied from the spray port 86 to the closed space HK in a state where the first electromagnetic valve 88 is closed and the exhaust port 87 is closed. When the pressure of the closed space HK exceeds the pressure set value, the first electromagnetic valve 88 is opened and the exhaust port 87 is opened. For this reason, the steam is injected into the closed space HK by setting the pressure setting value so that the pressure of the closed space HK when the steam is injected into the closed space HK does not exceed the pressure value at which the ink in the nozzle 46 is solidified. It is possible to suppress the ink in the nozzle 46 from being hardened due to the pressure increase in the closed space HK.

  (3) The steam injection cap 75 is provided with an openable / closable exhaust port 87. The first electromagnetic valve 88 is closed and the exhaust port 87 is closed. When the temperature of the closed space HK exceeds the temperature set value, the first electromagnetic valve 88 is opened and the exhaust port 87 is opened. For this reason, by setting the temperature setting value so that the temperature of the closed space HK when the steam is injected into the closed space HK does not exceed the temperature value at which the ink in the nozzle 46 is solidified, the steam is injected into the closed space HK. It is possible to suppress the ink in the nozzle 46 from solidifying due to the temperature rise of the closed space HK.

(4) Since the steam generating liquid is a liquid obtained by adding a preservative to pure water, the steam generating liquid can be prevented from being spoiled by the preservative.
(5) After the vapor of the vapor generating liquid is ejected to the liquid ejecting heads 24 </ b> A and 24 </ b> B including the nozzle 46, suction cleaning is performed in which ink is sucked and discharged from the opening of the nozzle 46. For this reason, unnecessary solidified ink or vapor generation liquid remaining in the nozzles 46 that have been clogged by the vapor ejection are discharged from the openings of the nozzles 46 together with the ink in the liquid ejection heads 24A and 24B. The Therefore, the ink in the nozzle 46 can be in a state where it can be ejected normally.

(Example of change)
In addition, you may change the said embodiment as follows.
The suction cap 70 may be omitted, and the vapor jet cap 75 may be used also as the suction cap 70. In this case, the suction pump 73 is provided at the end of the exhaust tube 91 opposite to the exhaust convex portion 90 side, and the end of the steam supply tube 92 on the injection convex portion 89 side and the second electromagnetic valve 93. In addition, an atmosphere release valve capable of opening the inside of the steam supply tube 92 to the atmosphere is provided. When suction cleaning is performed to suck and discharge ink from the opening of the nozzle 46, the suction pump 73 is opened with the first electromagnetic valve 88 opened and the atmosphere release valve and the second electromagnetic valve 93 closed. By this, the closed space HK is sucked. On the other hand, when the steam is injected into the nozzle 46, the steam from the steam injection device 74 is supplied to the steam supply tube with the first solenoid valve 88 and the atmosphere release valve closed and the second solenoid valve 93 opened. Injected from the injection port 86 to the closed space HK via the injection projections 92 and the injection projections 89.

  In the case where the vapor ejection cap 75 can be used also as the suction cap 70 as described above, after the vapor is ejected to the closed space HK, the liquid ejection head 24A, You may make it perform what is called pressurization cleaning which discharges the ink in 24B from the opening of the nozzle 46. FIG. That is, pressurization is performed in a state in which the pressure of the closed space HK is at least higher than the atmospheric pressure by the jet of steam while maintaining the state where the vapor jet cap 75 is in contact with the nozzle formation surface 24a of the liquid jet heads 24A and 24B. Ink is discharged from the opening of the nozzle 46 by driving the pump 96 to pressurize the ink in the liquid jet heads 24A and 24B. In this case, the differential pressure valve 31 is forcibly opened. After the pressure cleaning is completed, the vapor jet cap 75 is separated from the nozzle forming surface 24a of the liquid jet heads 24A and 24B in a state where the pressure in the closed space HK is at least higher than the atmospheric pressure. In this way, after performing the pressure cleaning, when the vapor jet cap 75 is separated from the nozzle formation surface 24a of the liquid jet heads 24A and 24B, air (atmosphere) flows from the opening of the nozzle 46 into the nozzle 46. Pulling in can be suppressed. Therefore, it is possible to suppress the occurrence of defective ejection of ink from the opening of the nozzle 46 due to the drawing of air into the nozzle 46.

  The moisturizing cap 71 may be omitted, and the vapor jet cap 75 may be used as the moisturizing cap 71. In this way, by covering each nozzle 46 with the vapor ejection cap 75, the ink in each nozzle 46 can be moisturized by the moisture remaining after the vapor is ejected into the vapor ejection cap 75. Further, for the purpose of keeping the ink in each nozzle 46 moist, steam may be supplied to a closed space HK formed by covering each nozzle 46 with a vapor jet cap 75.

  When the vapor from the vapor ejecting device 74 is ejected to the liquid ejecting heads 24A and 24B including the nozzle 46, the ink in the pressure chamber 44 communicating with the nozzle 46 is pressurized with the differential pressure valve 31 opened. You may make it pressurize with the pump 96. FIG. In this way, it is possible to suppress the vapor containing the droplets of the vapor generating liquid from entering the interior of the liquid jet heads 24 </ b> A and 24 </ b> B from the pressure chamber 44.

  The vapor generating liquid that is the second liquid may be composed of pure water only (pure water that does not contain preservatives). In this way, it is not necessary to set the heating temperature of the vapor generating liquid lower than the boiling point of the preservative. Further, when the vapor generating liquid is mixed with the ink in the nozzle 46, it is possible to suppress the vapor generating liquid from adversely affecting the ink.

  As a second liquid (vapor generating liquid) that is the same liquid as the main solvent of the ink used, the liquid is recovered by maintenance of the liquid jet heads 24A and 24B using the wiper unit 50, the flushing unit 51, the cap unit 52, and the like. Ink (waste ink) may be used. In this way, the amount of waste ink can be reduced. Further, even when the ink contains a preservative and the heating temperature of the vapor generating liquid is set higher than the boiling point of the preservative, the preservative contained in the second liquid (waste ink) is contained in the ink. Since it is the same as the preservative contained, it is possible to suppress the adverse effect on the ink caused by the vapor mixing with the ink in the nozzle 46.

  In the case of injecting steam to the clogged nozzle 46, the clogged nozzle 46 and the corresponding piezoelectric element portion 37a may be driven in the same manner as during ink ejection or flushing during printing. . Even if it does in this way, it can suppress that a vapor | steam approachs into the nozzle 46 which is clogged.

  When the steam is injected to the clogged nozzle 46, the nozzles 46 other than the clogged nozzle 46 and the nozzles 46 other than the clogged nozzle 46 are driven by driving the corresponding piezoelectric element portion 37a. The corresponding pressure chambers 44 may be pressurized respectively. If it does in this way, it can control that a vapor enters into nozzle 46 other than nozzle 46 which is clogged.

The steam injection device 74 may be arranged in the non-printing area NA on the side opposite to the home position HP side in the scanning direction X.
When the control unit 94 detects the nozzle 46 that does not clear the clogging even if the suction cleaning is performed a predetermined number of times based on the clogging detection history, the nozzle 46 that temporarily does not clear the clogging is not used. Alternatively, so-called complementary printing, in which printing is performed by ejecting ink with another normal nozzle 46, may be performed. In this case, the clogging may be eliminated with the steam from the steam injection device 74 in the nozzle 46 where the clogging is not eliminated even if the suction cleaning is performed a predetermined number of times after the complementary printing.

  The nozzle row 24b (nozzle 46) that ejects ink of a color (kind) that is used infrequently is used without regular maintenance (suction cleaning, flushing, wiping, etc.). You may make it eliminate clogging with the steam from the steam injection apparatus 74. FIG. In this way, the amount of ink used for suction cleaning and flushing of ink (type) of color that is very infrequent is reduced, so that the ink can be saved.

  The vapor generation unit 76 of the vapor ejection device 74 may function as a tank that collects waste ink generated by suction cleaning or the like. In this way, if the waste ink is water-based ink, it is possible to generate water vapor to be ejected to the nozzle 46 by heating the waste ink, so that the waste ink can be reused. In this case, the heating temperature of the waste ink is preferably higher than the boiling point of water and lower than the boiling point of the preservative contained in the waste ink. If it does in this way, it can control that antiseptic | preservative is contained in water vapor | steam.

  The inside of the printer main body 11a may be humidified with steam from the steam ejecting device 74. In this way, it is possible to suppress the generation of static electricity due to drying inside the printer main body 11a.

  When using ink containing synthetic resin that begins to harden at a relatively low temperature, when steam is jetted onto the liquid jet heads 24A and 24B including the nozzle 46, the pressure in the closed space HK is not increased too much. The opening / closing control of the first electromagnetic valve 88 and the second electromagnetic valve 93 may be performed to adjust the amount of steam discharged from the closed space HK and the amount of steam supplied to the closed space HK. In general, the temperature increases as the pressure in the closed space HK increases.

The vapor may be directly ejected from the vapor ejection unit 82 of the vapor ejection device 74 to the liquid ejection heads 24A and 24B including the nozzle 46.
In the state where the first electromagnetic valve 88 is closed and the exhaust port 87 is closed, the vapor of the vapor generating liquid is injected from the injection port 86 into the closed space HK, and the first electromagnetic valve is used regardless of the pressure value in the closed space HK. The valve closing state of 88 may be maintained.

  In the state where the first electromagnetic valve 88 is closed and the exhaust port 87 is closed, the vapor of the vapor generating liquid is injected from the injection port 86 into the closed space HK, and the first electromagnetic valve is used regardless of the temperature value of the closed space HK. The valve closing state of 88 may be maintained.

The first electromagnetic valve 88 and the second electromagnetic valve 93 may be open / close valves that are mechanically opened and closed using the driving force of various motors.
In the above embodiment, the liquid ejecting apparatus may be a liquid ejecting apparatus that ejects or discharges liquid other than ink. Note that the state of the liquid ejected as a minute amount of liquid droplets from the liquid ejecting apparatus includes a granular shape, a tear shape, and a thread-like shape. The liquid here may be any material that can be ejected from the liquid ejecting apparatus. For example, it may be in a state in which the substance is in a liquid phase, such as a liquid with high or low viscosity, sol, gel water, other inorganic solvents, organic solvents, solutions, liquid resins, liquid metals (metal melts ). Further, not only a liquid as one state of a substance but also a substance in which particles of a functional material made of a solid such as a pigment or a metal particle are dissolved, dispersed or mixed in a solvent is included. Typical examples of the liquid include ink and liquid crystal as described in the above embodiment. Here, the ink includes general water-based inks and oil-based inks, and various liquid compositions such as gel inks and hot melt inks. As a specific example of the liquid ejecting apparatus, for example, a liquid containing a material such as an electrode material or a color material used for manufacturing a liquid crystal display, an EL (electroluminescence) display, a surface emitting display, or a color filter in a dispersed or dissolved form. There is a liquid ejecting apparatus for ejecting the liquid. Further, it may be a liquid ejecting apparatus that ejects a bio-organic matter used for biochip manufacturing, a liquid ejecting apparatus that ejects liquid as a sample that is used as a precision pipette, a printing apparatus, a micro dispenser, or the like. In addition, transparent resin liquids such as UV curable resin to form liquid injection devices that pinpoint lubricant oil onto precision machines such as watches and cameras, and micro hemispherical lenses (optical lenses) used in optical communication elements. May be a liquid ejecting apparatus that ejects the liquid onto the substrate. Further, it may be a liquid ejecting apparatus that ejects an etching solution such as acid or alkali in order to etch a substrate or the like.

  DESCRIPTION OF SYMBOLS 11 ... Printer as an example of liquid ejecting apparatus, 24A, 24B ... Liquid ejecting head as an example of liquid ejecting section, 46 ... Nozzle, 74 ... Steam ejecting apparatus, 75 ... Steam ejecting cap as an example of cap, 76 ... Steam generation part, 82 ... Steam injection part, 86 ... Injection port, 87 ... Exhaust port, HK ... Closed space, ST ... Sheet as an example of medium.

Claims (8)

A liquid ejecting section capable of ejecting the first liquid from the nozzle opening to the medium;
A steam injection device having a steam generation unit that generates steam by heating the second liquid and a steam injection unit capable of injecting the steam generated by the steam generation unit;
The vapor ejecting apparatus ejects the vapor to the liquid ejecting unit including the nozzle in an atmosphere lower than the boiling point of the second liquid. A cap capable of defining a closed space in contact with the liquid ejecting unit and including an opening of the nozzle of the liquid ejecting unit;
2. The liquid ejecting apparatus according to claim 1, wherein the vapor ejecting apparatus ejects the steam into the closed space defined by the cap through an ejection port provided in the cap. The cap is provided with an openable and closable exhaust port,
The steam is injected through the injection port provided in the cap into the closed space defined by the cap in a state where the exhaust port is closed, and the pressure in the closed space exceeds a pressure setting value. The liquid ejecting apparatus according to claim 2, wherein the exhaust port is opened in some cases. The cap is provided with an openable and closable exhaust port,
The steam is injected through the injection port provided in the cap into the closed space defined by the cap in a state where the exhaust port is closed, and the temperature of the closed space exceeds a temperature setting value. The liquid ejecting apparatus according to claim 2, wherein the exhaust port is opened in some cases.   The liquid ejecting apparatus according to any one of claims 1 to 4, wherein the second liquid is a liquid obtained by adding a preservative to pure water. A liquid ejecting section capable of ejecting the first liquid from the nozzle opening to the medium;
A maintenance method for a liquid ejecting apparatus comprising: a steam generating section that heats a second liquid to generate steam; and a steam ejecting apparatus that includes a steam ejecting section capable of ejecting the steam generated by the steam generating section. And
A maintenance method for a liquid ejecting apparatus, comprising: ejecting the vapor to the liquid ejecting unit including the nozzle and then discharging the first liquid from an opening of the nozzle. The liquid ejecting apparatus includes a cap that can form a closed space in contact with the liquid ejecting unit and including an opening of the nozzle of the liquid ejecting unit,
Injecting the steam into the closed space defined by the cap through an injection port provided in the cap;
The first liquid is discharged from the opening of the nozzle in a state where the pressure of the closed space is at least higher than the atmospheric pressure by the vapor injection while maintaining the state where the cap is in contact with the liquid injection unit,
The maintenance method for a liquid ejecting apparatus according to claim 6, wherein the cap is separated from the liquid ejecting unit in a state where the pressure in the closed space is at least higher than atmospheric pressure.   8. The maintenance method for a liquid ejecting apparatus according to claim 7, wherein the discharge of the first liquid from the opening of the nozzle is performed by pressurizing the first liquid in the liquid ejecting unit.