JP5255718B2 - Inkjet head maintenance method, mechanism and apparatus - Google Patents

Description

  The present invention is for filling an ink jet head with ink when the ink cartridge is mounted / replaced, and for removing dust, dry ink, bubbles, and the like (hereinafter sometimes referred to as “maintenance”) of the ink ink jet head when printing is defective. The present invention relates to a method, a mechanism, and an apparatus.

  In general, an inkjet recording apparatus is provided with a maintenance mechanism in order to maintain ink ejection performance. As a conventional maintenance mechanism, after covering the nozzle surface of the inkjet head with a cap, the negative pressure suction pump is operated to operate the negative pressure suction pump to collect the waste ink from the inkjet head side. What to do is known.

  For example, in Patent Document 1, a cap that covers a nozzle surface of an inkjet head, a negative pressure suction pump that is connected to an ink discharge port of the cap via a connection tube, and a negative pressure suction pump that is connected to the negative pressure suction pump. A configuration including a waste ink tank that collects sucked waste ink is disclosed.

  In addition, the ink jet printer disclosed in Patent Document 2 has a print head having a plurality of nozzles, an opening common to the plurality of nozzles of the print head, and a plurality of suction ports, and the opening closely contacts the surface of the nozzle. A cap that forms a sealed space, at least one suction pump that sucks ink from the plurality of nozzles through the plurality of suction ports of the cap, and an ink flow path that connects the suction port and the suction pump of the cap, Ink is ejected from the nozzles of the print head to perform dot printing on the medium, and when the power is turned on or when necessary, the opening of the cap is brought into close contact with the nozzle and sucked by a suction pump.

Further, in Patent Document 3, a plurality of suction ports are provided in the suction cap, and the opening and closing operation of each valve of the communication path of each suction port is controlled, so that ink is appropriately filled in all channels at the time of initial ink introduction. It is disclosed that air bubbles can be efficiently removed from the channel near the end of the head where air bubbles tend to accumulate during regular purging.
JP 7-81089 A JP-A-7-304191 Japanese Patent No. 3800855 Japanese Patent No. 3597346

For inks that contain solids such as pigments, the viscosity is high and the fluidity of the ink itself is poor, so it is necessary to consume a large amount of expensive ink for the problem that maintenance takes considerable time and maintenance. There is a problem .

  SUMMARY OF THE INVENTION An object of the present invention is to solve the above technical problems, and to provide a maintenance method, mechanism, and apparatus for an ink jet head that can recover the ink ejection performance and can be satisfactorily applied without causing nozzle omission.

According to a first aspect of the present invention, there is provided a maintenance method for covering a nozzle of an ink jet head with a cap and generating a negative pressure to suck a liquid, a waste liquid tank communicating with the cap and the negative pressure generating means, and a low viscosity communicating with the ink jet head. a liquid reservoir, an ink reservoir communicating with the ink jet head is provided with a liquid switching means for alternatively communicated to the inkjet head and the low viscosity fluid reservoir or the ink reservoir, an ink reservoir and the ink jet head The first step of filling the ink until it reaches the liquid switching mechanism, the low-viscosity liquid reservoir and the inkjet head are communicated , a negative pressure is generated in the cap, and the inkjet head is filled with the low-viscosity liquid . second step, by communicating the ink reservoir and the ink-jet head inkjet f It is a maintenance method for an inkjet head characterized by having a third step of filling the ink into de.
A second invention is characterized in that, in the first invention, the first step is performed when ink is initially filled in a communication member that communicates the ink storage portion and the liquid switching mechanism .
According to a third aspect of the present invention, in the first or second aspect of the present invention, the liquid is supplied into the cap while the nozzle is covered with the cap from the end of the suction of the liquid until the coating process is started, and is exposed at the tip of the nozzle. The ink is prevented from drying .

According to a fourth aspect of the present invention, there is provided a maintenance method for covering a nozzle of an ink jet head with a cap and generating a negative pressure to suck a liquid, a waste liquid tank communicating with the cap and the negative pressure generating device, and a low viscosity communicating with the ink jet head. A liquid storage unit, an ink storage unit communicating with the inkjet head, and a liquid switching mechanism that selectively communicates the inkjet head with the low viscosity liquid storage unit or the ink storage unit are provided. Ink jet head maintenance method in which a negative pressure is generated in the cap to fill the inkjet head with a low-viscosity liquid, and the ink reservoir and the inkjet head are then communicated to fill the inkjet head with ink. To recover the liquid supplied in the cap. A re-supply tank (18) and a pressure supply pump (17) for re-supplying the liquid in the re-supply tank to the cap, and a nozzle between the end of liquid suction and the start of the coating process An ink jet head maintenance method, wherein the ink in the resupply tank is accumulated in the cap while the ink is covered with the cap to prevent the ink exposed at the tip of the nozzle from drying .
A fifth invention is characterized in that, in any one of the first to fourth inventions, the liquid switching mechanism is disposed in the vicinity of the inkjet head .
A sixth invention is characterized in that, in any one of the first to fifth inventions, the low-viscosity liquid is an ink solvent .

A seventh aspect of the present invention is a maintenance mechanism for covering a nozzle of an inkjet head with a cap and generating a negative pressure to suck a liquid, and a cap that contacts the inkjet head to cover the nozzle and generates a negative pressure on the cap A negative pressure generating device, a cap and a waste liquid tank communicating with the negative pressure generating device, a cap opening / closing mechanism for contacting or non-contacting the cap with the inkjet head, a low-viscosity liquid reservoir communicating with the inkjet head, and an inkjet An ink reservoir that communicates with the head, a liquid switching mechanism that selectively communicates the inkjet head with the low-viscosity liquid reservoir or the ink reservoir, and a controller that controls these operations. The ink storage unit and the inkjet head to communicate with each other until reaching the liquid switching mechanism. A first step of filling, a second step of communicating the low-viscosity liquid reservoir and the inkjet head, and generating a negative pressure in the cap to fill the inkjet head with the low-viscosity liquid; an ink reservoir and the inkjet head; A maintenance mechanism for an inkjet head, wherein a third process of filling the inkjet head with ink in communication is performed.
An eighth invention is characterized in that, in the seventh invention, the control unit implements the first step when the ink is initially filled in the communication member that communicates the ink storage unit and the liquid switching mechanism. To do.

A ninth aspect of the present invention is a maintenance mechanism for covering a nozzle of an ink jet head with a cap and generating a negative pressure to suck a liquid, the cap contacting the ink jet head and covering the nozzle, and generating a negative pressure on the cap. A negative pressure generating device , a cap and a waste liquid tank communicating with the negative pressure generating device , a cap opening / closing mechanism for contacting or non-contacting the cap with the inkjet head, a low-viscosity liquid reservoir communicating with the inkjet head, and an inkjet An ink reservoir that communicates with the head, a liquid switching mechanism that selectively communicates the inkjet head with the low-viscosity liquid reservoir or the ink reservoir, a liquid feed mechanism for supplying liquid into the cap, and and a control unit for controlling the operation, the liquid feed mechanism recovers the supplied liquid in the cap A supply tank (18), and a pressure supply pump for re-supplying the liquid to the cap in the resupply tank (17), wherein the control unit is communicated with the low-viscous liquid reservoir and the ink jet head, a negative by generating a pressure in the cap to fill the low-viscous liquid to the ink jet head, followed by filling the ink jet head communicates with an ink reservoir and the ink jet head, and a coating step after completion aspiration of liquid A maintenance mechanism for an ink jet head that prevents drying of ink exposed at the tip of a nozzle by storing liquid in a resupply tank in the cap while the nozzle is covered with a cap until the start. .
A tenth invention is characterized in that, in any of the seventh to ninth inventions, the liquid switching mechanism is disposed in the vicinity of the ink jet head .
An eleventh invention is characterized in that, in any of the seventh to tenth inventions, the low-viscosity liquid is an ink solvent .

A twelfth aspect of the invention is an apparatus having an ink jet head maintenance mechanism according to any of the seventh to eleventh aspects of the invention.

According to the present invention, ink can be filled without mixing bubbles.
In addition, it is possible to reduce the amount of ink consumed for maintenance, and to reduce the time required for maintenance.

The maintenance mechanism of the present invention can be used for various ink jet recordings. Hereinafter, the best mode for carrying out the present invention will be described using an ink jet printer as an example.
The maintenance mechanism of the present invention is for filling the ink-jet head 1 with ink when the ink cartridge is mounted / replaced, and for removing dust, dry ink, bubbles, etc. from the ink-jet head 1 when printing is defective. The inkjet head 1 includes one or a plurality of nozzles configured by extending cylinders, holes formed in a plane, or the like.
The maintenance mechanism of the present invention includes a liquid switching unit 4 and a second tank for storing a low-viscosity liquid 32, and the liquid switching unit 4 switches between the ink 31 and the low-viscosity liquid 32 to fill the liquid accompanying maintenance. be able to. For this reason, before the ink 31 is filled in the ink-jet head 1, the ink 31 can be filled after the filling with the low-viscosity liquid 32 having a high fluidity and the removal of bubbles. Not only can the ink consumption be reduced, but also the ink filling time can be shortened.
The liquid switching means 4 is preferably provided in the vicinity of the inkjet head 1. This is because the consumption of the ink 31 can be further suppressed by adopting a configuration in which both liquids enter until the entrance of the liquid switching means 4.
As the low-viscosity liquid 32, a liquid having a low viscosity and high fluidity can be used. However, a liquid that functions as a cleaning liquid is preferable. Examples are solvents that dissolve liquids and inks.

In general, inks used in inkjet printers can be classified as dye-based or pigment-based. A dye is a colorant that is dispersed or solvated as a molecule in a carrier medium. The carrier medium is liquid or solid at room temperature. A commonly used carrier medium is water or a mixture of water and an organic cosolvent. In general, water is used as a main component, and a coloring agent and a wetting agent such as glycerin are contained for the purpose of preventing clogging. When water is used as the carrier medium, such inks also generally have the disadvantage of poor water fastness.
A pigment is a colorant that is insoluble in the carrier medium, but is dispersed or suspended in the form of small particles and is often stabilized by the use of a dispersant so that it does not agglomerate and precipitate. Many such compounds are known. For example, a pigment ink used as a colorant by finely pulverizing a pigment such as an organic pigment or carbon black using a surfactant or a dispersant and dispersing it in a medium such as water. and so on.
The maintenance mechanism of the present invention can be applied regardless of the dye system or the pigment system. The mainstream ink viscosity is as low as several tens of cps, but it can be applied to medium viscosity of several hundred cps or higher as long as it can be ejected by flight.
The present invention can also be applied to functional inks used for wiring pattern printing on printed boards, application of lubricants to minute parts, outdoor light-resistant display material printing, UV curable ink printing, and the like.

  In addition, the maintenance mechanism of the present invention includes a negative pressure adjusting means 5 comprising an electropneumatic regulator 51 that can be adjusted to a flow rate according to an external signal waveform pattern, and an ejector 52 that can adjust the negative pressure according to the value of the flow rate. Prepare. In the conventional maintenance mechanism, since the negative pressure in the cap 2 is suddenly returned to the atmospheric pressure, the flow of the ink 31 discharged from the nozzle 6 also stops suddenly, and the meniscus (liquid bridge) at the tip of the nozzle 6 is stopped. At this time, bubbles were generated (remixed) in the flow path, but in the present invention, the negative pressure in the cap 2 can be returned to the atmospheric pressure with a desired waveform signal. It is possible to prevent re-mixing of bubbles without applying vibration to the meniscus at the tip.

By the way, when the ink 31 is filled with a negative pressure, the adhesion between the head surface of the inkjet head 1 and the cap 2 is important. The contact member 21 of the cap 2 can be made of an elastic body having a high hardness, so that the adhesiveness can be improved. There is a problem that occurs. On the other hand, if the hardness of the abutting member 21 of the cap 2 is softened, the abutting member 21 is deformed by a negative pressure and a gap is generated.
Therefore, in the present invention, by adopting a structure that can follow the inclination of the head surface, it is possible to ensure the adhesion and sealing performance of the cap 2. That is, the abutting member 21 that abuts the head surface is made of a hardened elastic body to improve adhesion, and is supported by the supporting member 23 that supports the abutting member 21 (and the frame 22) with a soft elastic body. Thus, the degree of freedom to follow the inclination of the head surface is provided, and the sealing performance can be maintained.

  Hereinafter, the details of the present invention will be described with reference to examples, but the present invention is not limited to these examples.

FIG. 1 is a configuration diagram of a maintenance mechanism of the ink jet coating apparatus according to the present embodiment.
The inkjet head 1 has a plurality of nozzles 6 and performs printing or the like by ejecting ink 31 stored in a first tank 11 communicated by a communication member 9. Maintenance of the inkjet head 1 is performed by covering the nozzle 6 with the cap 2, generating a negative pressure in the cap 2, and discharging the sucked ink or the like to a waste liquid tank 14 communicated with the cap 2 by the communication member 9. The contact between the cap 2 and the inkjet head 1 is automatically performed by the cap opening / closing means 3. The cap opening / closing means 3 may be a device that relatively moves the inkjet head 1 or a device that relatively moves the cap 2. In some industrial fields, the cap 2 may be manually opened and closed.

  The maintenance mechanism of the present embodiment has the above-described publicly-known configuration, the second tank 12 communicated with the inkjet head 1 by the communication member 9, and the communication between the inkjet head 1 and the first tank 11 or the second tank 12. And a liquid switching means 4 for selectively switching between them. The second tank 12 stores a low-viscosity liquid 32 that flows first when maintenance starts. In this embodiment, a solvent (cleaning liquid) that dissolves the ink 31 is used for the low viscosity liquid 32. Thereby, even when the ink 31 is consolidated in the flow path, it can be dissolved.

In addition, as shown in FIG. 2, the cap 2 of this embodiment is configured to have a degree of freedom that can follow the inclination of the head surface.
The abutting member 21 that abuts the head surface is made of rubber having a Shore A hardness of 40 to 80 degrees (preferably 50 to 70 degrees) (JIS K 6253 standard), which is a hard elastic body, and is bonded to the upper surface of the frame 22 It is attached by screwing.
The frame 22 is supported by a support member 23 formed of a soft elastic member (for example, rubber or spring) fixed by bonding or screwing. The support member 23 should have a penetration of 40 to 80 (preferably 50 to 70 degrees) so that it can follow an attachment error (three-dimensional inclination) of the nozzle surface of the inkjet head 1. The support member 23 is fixed to the plate-like attachment member 24. A joint 26 that can connect at least one suction through hole 25 and the communication member 9 is disposed on the bottom surface of the frame 22.
According to the cap 2 of the present embodiment configured as described above, complete adhesion and sealing performance can be ensured without being affected by the inclination of the nozzle surface.

The negative pressure generating means 5 of the present embodiment includes a signal generating means 15, a pressure supply pump 16, a regulator 51, and an ejector 52, and communicates with the cap 2 through the waste liquid tank 14. A silencer 53 that absorbs air sound may be added to the negative pressure generating means 5.
The signal generator 15 can set and register signal waveforms of time and voltage of a plurality of patterns, and can select and output only one pattern from the plurality of registered patterns. The regulator 51 can supply pressure according to the voltage of the signal waveform of the signal generating means 15. The signal generating means 15 may be composed of, for example, a pulse generator or a PC.
The ejector 52 can generate a negative pressure according to the pressure supplied from the regulator 51. The regulator 51 and the ejector 52 can be configured by commercially available pneumatic equipment.
Even if the negative pressure generated by the ejector 52 is not controlled by the regulator 51, the negative pressure is controlled by adjusting the throttle amount of the throttle valve provided on the disposal side of the ejector 52 while maintaining a constant pressure from the regulator 51. May be.

The negative pressure generating means 5 of this embodiment is characterized in that the negative pressure generated in the cap 2 is gradually returned to atmospheric pressure. That is, in this embodiment, it is possible to prevent the re-mixing of bubbles by causing the negative pressure change in the cap 2 to occur gently by the signal generating means 15 that generates a preset signal waveform.
As long as the negative pressure in the cap 2 changes gently, the signal waveform to be set may be linear or curvilinear, or may be a signal waveform that changes finely in steps. An example of the curved waveform is a Sin waveform as shown in FIG. As shown in FIG. 3A, when the signal waveform output from the signal generating means 15 is a Sin waveform, the pressure supplied from the regulator 51 changes as shown in FIG. The pressure becomes as shown in FIG. 3C, and vibration can be prevented from being applied to the meniscus at the tip of the nozzle 6 of the inkjet head 1.

Details of the maintenance procedure in this embodiment will be described with reference to FIG. In the following, a filling flow at the time of ink cartridge installation / replacement (initial time or ink replenishment) is described.
<< First Phase >>
First, the ink 31 is filled into the communication member 9. The first valve 41 of the liquid switching means 4 is opened and the second valve 42 is closed (STEP 1), and the negative pressure generating means 5 is activated based on a preset time to make the inside of the cap 2 have a negative pressure. The ink 31 is guided to the connecting member 9 (STEP 2). By generating the negative pressure for a preset time, the ink 31 is filled up to the first valve 41 of the communication member 9 (STEP 3). Here, the preset time is the time until the ink 31 reaches the first valve 41 of the communication member 9 from the first tank 11. After the elapse of a preset time, the generation of the negative pressure is stopped, whereby the inside of the cap 2 returns to the atmospheric pressure, and the suction is stopped (STEP 4). It should be noted that the stop of the generation of the negative pressure in the first phase does not need to cause the negative pressure to change gradually.
<< Second Phase >>
Next, the low viscosity liquid 32 is filled into the nozzle 6. The first valve 41 of the liquid switching means 4 is closed and the second valve 42 is opened (STEP 5), and the negative pressure generating means 5 is activated based on a preset time to make the inside of the cap 2 have a negative pressure. The low viscosity liquid 32 is filled (STEP 6). By generating the negative pressure for a preset time, the low-viscosity liquid 32 is filled in the communication member 9 and then filled in the inkjet head 1 (STEP 7). Here, the preset time is a time during which the low viscosity liquid 32 is reliably discharged from the tip of the nozzle 6. After the elapse of a preset time, the generation of the negative pressure is stopped, whereby the inside of the cap 2 returns to the atmospheric pressure, and the suction is stopped (STEP 8). Note that the stop of the generation of the negative pressure in the second phase does not need to cause the negative pressure to change gradually.
《Third phase》
Finally, the ink 31 is filled into the nozzle 6. The first valve 41 of the liquid switching means 4 is opened and the second valve 42 is closed (STEP 9), and the negative pressure generating means 5 is activated based on a preset time and signal waveform to move inside the cap 2. The ink 31 filled up to the first valve 41 as a negative pressure is guided to the inkjet head 1 (STEP 10). By generating the negative pressure for a preset time, the ink 31 is filled in the inkjet head 1 (STEP 11). Here, the preset time is a time during which the ink 31 is reliably discharged from the tip of the nozzle 6. After the elapse of a preset time, the generation of the negative pressure is gently stopped based on a preset signal waveform, whereby the inside of the cap 2 is gradually returned to the atmospheric pressure, and the suction is stopped (STEP 12). Here, the above-described Sin waveform is disclosed as a preset signal waveform, but is not limited thereto.

By going through the above procedure, bubbles between the first tank 11 and the first valve 41 are driven in the first phase, and bubbles between the second tank and the nozzle 6 are driven by the low viscosity liquid 32 in the second phase. Is discharged, the ink is filled in the third phase, and the negative pressure is released based on a preset signal waveform, whereby the ink jet head 1 can be filled with the ink 31 without leaving bubbles.
Note that the maintenance in the case other than when the ink cartridge is mounted / replaced does not require the first phase, so only the second and third phases need be performed. When the ink cartridge is mounted / replaced, if the ink does not reach the liquid switching means 4, bubbles are filled in the ink-jet head 1, so the first phase is necessary.

FIG. 5 is a configuration diagram of the maintenance mechanism of the present embodiment, and FIG. 6 is a schematic perspective view of a desktop inkjet coating apparatus equipped with the maintenance mechanism of the present embodiment.
In the apparatus of the present embodiment, as shown in FIG. 6, three inkjet heads 1 arranged in the Y direction are arranged in the Z direction moving means 64. The work table 61 is movable in the Y direction, and the Z direction moving means 64 is movable in the X direction by an X direction moving means 63 provided on the beam 62. The three caps 2 are arranged at intervals facing the inkjet head 1. In FIG. 6, reference numeral 11 is a first tank in which ink 31 is stored, reference numeral 12 is a second tank in which low-viscosity liquid 32 is stored, and reference numeral 13 is a third tank in which dissolved solution 33 is stored. The tank. In FIG. 6, the waste liquid tank 14, the resupply tank 18, the electric system wiring, and the liquid feeding system piping are omitted.

The main difference in configuration between the maintenance mechanism of the present embodiment and the first embodiment is that it has a third tank 13 and a resupply tank 18.
A solution 33 is stored in the third tank 13 of the maintenance mechanism of the present embodiment. The solution 33 is an inexpensive material that easily absorbs air, and ammonia water is used in this embodiment.

The resupply tank 18 is for resupplying the low viscosity liquid 32 to the cap 2. The significance of resupplying the low viscosity liquid 32 to the cap 2 is to prevent the evaporation of the ink 31 exposed at the tip of the nozzle 6. The ink 31 evaporates after the maintenance process is completed and before the coating process is started. When the ink 31 evaporates, the ink 31 increases in viscosity, and the accuracy of the ejection amount and the landing position decreases. As the viscosity increases, the ink 31 does not fly. For this reason, in order to prevent evaporation of the ink 31, it is preferable to keep the cap 2 in contact with the inkjet head 1. However, this alone may not sufficiently prevent the evaporation of the ink 31. Therefore, by setting the low-viscosity liquid 32 in the concave portion of the cap 2 facing the nozzle 6, it is possible to prevent the ink 31 from being evaporated more effectively. The low-viscosity liquid 32 is supplied by applying a positive pressure to the resupply tank 18 by the pressure supply pump 17.
In the present embodiment, the low-viscosity liquid 32 is supplied to prevent evaporation, but the same effect can be obtained as long as the liquid is mainly composed of water and does not remain in the cap 2.

The maintenance procedure in the present embodiment is performed by first filling the ink-jet head 1 with the solution 33, then filling the low-viscosity liquid 32, and finally filling the ink 31.
The liquid sucked by the negative pressure is separated into the waste liquid tank 14 and the resupply tank 18. That is, the ink 31 and the solution 33 are discharged to the waste liquid tank 14, and the low viscosity liquid 32 is discharged to the resupply tank 18.
The desktop ink jet coating apparatus having the maintenance mechanism of the present embodiment configured as described above, in addition to the effects of the first embodiment, evaporates the ink 31 from the end of the maintenance process to the start of the coating process. It has the effect of reliably preventing it.

The present invention is not limited to an ink jet printer, and can be applied to various ink jet recordings such as a precision spray / injection device (including a coating device), a precision coating device, and the like. Ink-jet patterning, for example, printing on organic EL display panels and large color panels, and application to a coating device, a drawing device, and a printing device for industrial marking, etc. are also possible.
The ink jet recording method can be applied regardless of a mechanical conversion method such as a piezo method and a bubble generation method such as a resistance heating jet method.
It can also be used in the lens coloring process in the lens manufacturing industry, and in posters and building material decoration in the large printing industry.

1 is a configuration diagram of a maintenance mechanism according to Embodiment 1. FIG. It is a block diagram of the cap shown transparently. 3 is a signal waveform output from the devices according to the first embodiment. 2 is a filling flow of Example 1. 6 is a configuration diagram of a maintenance mechanism according to Embodiment 2. FIG. 6 is a schematic perspective view of a desktop ink jet coating apparatus equipped with a maintenance mechanism according to Embodiment 2. FIG.

DESCRIPTION OF SYMBOLS 1 Inkjet head 2 Cap 3 Cap opening / closing means 4 Liquid switching means 5 Negative pressure generating means 6 Nozzle 9 Communication member 11 First tank 12 Second tank 14 Waste liquid tank 15 Signal generating means 16 (for negative pressure) Pressure supply pump 17 ( Pressure supply pump 18 for positive pressure Resupply tank 21 Contact member 22 Frame 23 Support column 24 Mounting member 25 Through hole 26 Joint 31 Ink 32 Low viscosity liquid 33 Dissolved liquid 34 Waste liquid 41 First valve 42 Second valve 43 Second 3 valve 44 4th valve 45 5th valve 51 regulator 52 ejector 53 silencer 61 work table 62 beam 63 X direction moving means 64 Z direction moving means 67 power switch 68 communication connector

Claims (12)

In the maintenance method of covering the nozzle of the inkjet head with a cap and generating a negative pressure to suck the liquid,
Select a waste liquid tank that communicates with the cap and the negative pressure generator, a low-viscosity liquid reservoir that communicates with the inkjet head, an ink reservoir that communicates with the inkjet head, and an inkjet head and low-viscosity liquid reservoir or ink reservoir. A liquid switching mechanism for communicating with each other;
A first step of filling the ink until the ink reservoir and the inkjet head are communicated to reach the liquid switching mechanism ;
A second step of communicating the low-viscosity liquid reservoir and the inkjet head and generating a negative pressure in the cap to fill the inkjet head with the low-viscosity liquid;
A third step wherein the be s link maintenance method of the jet head to have a filling ink to an ink jet head communicates with an ink reservoir and the ink jet head. The first maintenance method for an inkjet head according to claim 1, characterized in that a step at the time of initial filling of the ink communicating member for communicating the liquid changing mechanism ink reservoir. The liquid is supplied into the cap in a state where the nozzle is covered with the cap from the end of the suction of the liquid to the start of the coating process, and drying of the ink exposed at the tip of the nozzle is prevented. Maintenance method of 1 or 2 inkjet head. In the maintenance method of covering the nozzle of the inkjet head with a cap and generating a negative pressure to suck the liquid,
Select a waste liquid tank that communicates with the cap and the negative pressure generator, a low-viscosity liquid reservoir that communicates with the inkjet head, an ink reservoir that communicates with the inkjet head, and an inkjet head and low-viscosity liquid reservoir or ink reservoir. A liquid switching mechanism for communicating with each other;
The low-viscosity liquid reservoir and the inkjet head communicate with each other, a negative pressure is generated in the cap to fill the inkjet head with the low-viscosity liquid, and the ink reservoir and the inkjet head communicate with each other to fill the inkjet head with ink. A maintenance method for an inkjet head,
A resupply tank (18) for recovering the liquid supplied in the cap, and a pressure supply pump (17) for resupplying the liquid in the resupply tank to the cap;
From the end of liquid suction to the start of the coating process , the liquid in the resupply tank is stored in the cap while the nozzle is covered with the cap, thereby preventing drying of the ink exposed at the nozzle tip. maintenance method of Louis ink jet head to the. The liquid switching mechanism, according to claim 1 to any of the maintenance method of the inkjet head 4, characterized in that arranged in the vicinity of the inkjet head. The low viscosity liquid, according to claim 1 to any of the maintenance method of an ink jet head 5, characterized in that the solvent of the ink. A maintenance mechanism that covers a nozzle of an inkjet head with a cap and generates a negative pressure to suck a liquid,
A cap that contacts the inkjet head and covers the nozzle, a negative pressure generating device that generates negative pressure in the cap, a waste liquid tank that communicates with the cap and the negative pressure generating device, and a cap that contacts or non-contacts the inkjet head A cap switching mechanism, a low-viscosity liquid reservoir that communicates with the inkjet head, an ink reservoir that communicates with the inkjet head, and a liquid switching mechanism that selectively communicates the inkjet head with the low-viscosity liquid reservoir or the ink reservoir. And a control unit for controlling these operations,
The control unit causes the ink storage unit and the inkjet head to communicate with each other and fills the ink until reaching the liquid switching mechanism . The low-viscosity liquid storage unit communicates with the inkjet head, and the negative pressure is applied to the cap. a second step of filling the low viscosity liquid is generated in the ink jet head, by communicating the ink reservoir and the ink jet head, wherein the to Louis ink to implement the third step of filling the ink jet head Jet head maintenance mechanism. 8. The maintenance mechanism for an ink jet head according to claim 7 , wherein the control unit performs the first step when initially filling ink into a communication member that communicates the ink storage unit and the liquid switching mechanism. A maintenance mechanism that covers a nozzle of an inkjet head with a cap and generates a negative pressure to suck a liquid,
A cap that contacts the inkjet head and covers the nozzle, a negative pressure generating device that generates negative pressure in the cap, a waste liquid tank that communicates with the cap and the negative pressure generating device, and a cap that contacts or non-contacts the inkjet head A cap switching mechanism, a low-viscosity liquid reservoir that communicates with the inkjet head, an ink reservoir that communicates with the inkjet head, and a liquid switching mechanism that selectively communicates the inkjet head with the low-viscosity liquid reservoir or the ink reservoir. And a liquid feeding mechanism for supplying liquid into the cap, and a control unit for controlling these operations,
The liquid feeding mechanism includes a resupply tank (18) for recovering the liquid supplied in the cap, and a pressure supply pump (17) for resupplying the liquid in the resupply tank to the cap.
The control unit causes the low-viscosity liquid storage unit and the inkjet head to communicate with each other, generates a negative pressure in the cap to fill the inkjet head with the low-viscosity liquid, and then causes the ink storage unit and the inkjet head to communicate with each other to perform inkjet. Fill the head with ink, and after the suction of the liquid until the coating process starts , the liquid in the re-supply tank is exposed to the nozzle tip while the nozzle is covered with the cap. features and to Louis inkjet head maintenance mechanism to prevent drying of the ink. The liquid switching mechanism, one of the ink-jet head maintenance mechanism of claims 7, characterized in that it is disposed near the ink jet head 9. The low viscosity liquid is characterized in that the solvent of the ink claims 7 to 10 either ink jet head maintenance mechanism of. Device having a maintenance mechanism of any of the ink jet head of claims 7 to 11.