JPH05201028A - Maintenance device for ink jet head - Google Patents

Abstract

PURPOSE:To ensure jet stability of an ink jet head by a method wherein a water-repellent thin layer on the end surface of a head body is not unnecessarily damaged and unnecessary ink inside and outside a nozzle is surely removed, consuming a minimum amount of ink required, and clogging of nozzle can be obviated and further clogging of nozzle can be surely removed. CONSTITUTION:There is provided a maintenance device for an ink jet head wherein a number of nozzles 2 are arranged in a head body 1 and one end of the body 1 is formed into a flat plane, said device comprising a negative pressure generating means 3 for generating negative pressure lower than the atmospheric pressure, a local drawing means 4 connected to the means 3 so as to communicate therewith, wherein a drawing opening 5 facing one or more units of nozzles 2 has a size corresponding to the region occupied by them, and a drawing opening moving means 6 for moving the port 5 of the means 4 in the direction of arrangement of the nozzles 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet head maintenance device, and more particularly to an ink jet head in which a large number of nozzles are formed in an array in the head body and the end portion of the head body is formed flat. The present invention relates to a maintenance device that removes unnecessary ink inside / outside of nozzles for preventing nozzle clogging, recovering nozzle clogging, and stabilizing jetting.

[0002]

2. Description of the Related Art As a conventional multi-nozzle type ink jet head, for example, as shown in FIG.
It is already provided that a large number of nozzles 201 are formed in the head main body 200 in an array at a predetermined pitch and the ends of the head main body 200 are formed in a flat shape. Conventionally, as a maintenance device for this type of inkjet head, a so-called vacuum suction method (Japanese Patent Laid-Open Nos. 62-113556 and 63-63) is used.
No. 295265) or a so-called wiping method (see Japanese Patent Laid-Open No. 62-251146). Here, in the vacuum suction type maintenance device, as shown in FIG. 15, the entire end surface exposed by each nozzle 201 surface of the head main body 200 is covered with a cap 202,
The inside of the cap 202 is set to a negative pressure state to suck and remove the unnecessary ink inside and outside the nozzle. On the other hand, the wiping-type maintenance device uses the wiper member to attach unnecessary ink to the end surface of each nozzle surface of the head body exposed. Is to be wiped off.

[0003]

However, in the above-mentioned vacuum suction type maintenance device,
As shown in FIG. 15, each nozzle 20 of the head main body 200
When the entire end surface exposed on one surface is covered with the cap 202 and the inside of the cap is in a negative pressure state, negative pressure acts on all the nozzles 201 at the same time, and a large amount of ink 203 is discharged from the nozzles 201 that are not clogged. There is a concern that not only the ink will be washed away and the running cost will be high, but also a large amount of the ink 203 will flow out and sufficient pressure will not be applied to the nozzle 201 that is clogged with dust 204, and recovery of the clogging will be incomplete.

Further, in the wiping type maintenance device, since the ink adhered to the end surface of the head main body is wiped off by the wiper member, the end surface of the head main body is normally provided with a nozzle for stabilizing the printing operation. Although the liquid-repellent treatment thin layer is applied, there is a concern that the liquid-repellent treatment thin layer may be easily worn by the wiper member or may be peeled off, and dust on the wiper member itself may push dust into the nozzle. A technical problem arises.

The present invention has been made in order to solve the above technical problems, and does not unnecessarily damage the liquid treating thin layer or the like on the end surface of the head body, and consumes a minimum amount of ink. Of the inkjet head that reliably removes unnecessary ink inside and outside the nozzle to prevent the nozzle from clogging and to reliably recover the clogging of the nozzle to ensure the ejection stability of the inkjet head. A maintenance device is provided.

[0006]

That is, the present invention is
As shown in FIG. 1A, a maintenance device for an ink jet head in which a large number of nozzles 2 are formed in an array in the head body 1 and the end portion of the head body 1 is formed in a flat shape, and is a negative pressure lower than atmospheric pressure. Negative pressure generating means 3 for generating pressure,
A local suction means 4 which is connected to the negative pressure generating means 3 and has a suction opening 5 having a size facing one or several units of the nozzle 2 region, and the suction opening 5 of the local suction means 4. And a suction opening moving means 6 for relatively moving the nozzles in the arrangement direction of the nozzles 2.

In such a technical means, if the local suction means 4 has a suction opening 5 having a size facing one or several units of the nozzle 2 region, the suction opening 5 will be the same. The shape may be circular, elliptical or polygonal. Regarding the size of the suction opening 5, experimentally, the opening dimension R of the suction opening 5 in the nozzle 2 array direction is at least r <R with respect to the opening dimension r of the nozzle 2.
It may be set to <40r, but in order to ensure the recovery performance of the clogging of the nozzle 2, it is preferable to provide the suction opening 5 having a size facing one nozzle 2 region.

Further, in the case of the type in which the local suction means 4 slides along the end surface including the nozzle 2 surface of the head body 1, the liquid repellent treatment for stabilizing the printing operation of the nozzle 2 on the end surface of the head body 1 From the viewpoint of effectively avoiding the situation where the thin layer is unnecessarily worn or peeled off, at least the contact portion of the local suction means 4 with the head body 1 may be formed of a material having a small frictional resistance. In order to more surely avoid abrasion of the liquid-repellent thin layer on the end surface of the head body 1, as shown in FIG. 1B, at least the local suction means 4 and the nozzle 2 surface of the end surface of the head body 1 are provided. It is preferable to provide the gap holding means 7 for holding the neighboring portions in a non-contact state.

Further, the suction opening moving means 6 is preferably operated automatically in consideration of operability,
The present invention is not limited to this, and manual operation may be used. Further, as the suction opening moving means 6, if the suction opening 5 of the local suction means 4 can relatively move with respect to the head body 1, the head body 1 is fixedly arranged at a predetermined position. The suction means 4 may be moved, or the local suction means 4 may be fixedly arranged at a predetermined position to move the head body 1, or the local suction means 4 and the head body 1 may be moved. Are fixedly arranged at predetermined positions respectively, and the suction opening 5 of the local suction means 4 is provided.
It is possible to appropriately change the design such that a plurality of branches are formed in advance and the suction openings 5 are sequentially switched and selected to substantially move the suction openings 5.

The negative pressure acting on the local suction means 4 may be such that ink clogging the nozzles 2 facing the suction openings 5 can be removed (exceeding ₂₀ cmH ₂ O). Further, the negative pressure acting on the local suction means 4 is basically the uniform pressure generated by the negative pressure generation means 3, but in order to more reliably avoid the clogging of the nozzle 2, the negative pressure shown in FIG. As indicated by phantom lines in a) and (b), the negative pressure generated by the negative pressure generating means 3 is appropriately changed by the pressure changing means 8 so that the pumping action is added to the suction operation of the local suction means 4. Is preferred.

Further, from the viewpoint of further reducing the ink consumption, the clogging state of each nozzle 2 is detected in advance, and the suction operation of the local suction means 4 is performed only for the nozzle 2 in the clogging state. You may make it perform intensively. In this case, as a means for detecting the clogging state of each nozzle 2, for example, a pressure sensor or a flow rate sensor is provided in the piping system between the negative pressure generating means 3 and the local suction means 4, and the local suction means is used. 4 performs a suction operation with a weak suction force (to the extent that ink is not sucked), generates clogging data according to the change information of the pressure sensor, the flow rate sensor, etc. at that time, and locally based on this clogging data. The suction operation of the suction means 4 may be controlled.

[0012]

According to the above-mentioned technical means, when the negative pressure generating means 3 generates a negative pressure lower than the atmospheric pressure, the suction opening 5 portion of the local suction means 4 becomes a negative pressure state of a desired level or higher. .. Then, when the suction openings 5 are relatively moved by the suction opening moving means 6 along the nozzle arrangement direction of the head body 1, the suction openings 5 of the local suction means 4 become one or several nozzles 2 area. Since the negative pressure acting on the ink inside and outside the nozzles 2 is kept at a desired level or higher, unnecessary matters (high-viscosity ink, dust, air bubbles) inside and outside each nozzle 2 are maintained. Others) are removed by suction through the local suction means 4. At this time, in the gap holding means 7, the local suction means 4 is used for the nozzles 2 on the end surface of the head body 1.
It prevents the contact with the vicinity of the surface and suppresses the abrasion of the liquid-repellent thin layer for stabilizing the printing operation of the end surface of the head body 1. Further, when the pressure changing means 8 changes the pressure acting on the inside and outside of the nozzle 2, unnecessary substances (high-viscosity ink, dust, air bubbles, etc.) are more reliably removed with a smaller pressure.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail based on the embodiments shown in the accompanying drawings. Example 1 FIGS. 2 to 4 show Example 1 of an inkjet head maintenance device to which the present invention is applied. In the figure, the inkjet head 10 comprises a head body 11 and a heat sink 12. The head body 11 is connected to an ink tank (not shown). Inside the head body 11, 192 nozzles 13 are linearly arranged at a density of 300 per inch, and each nozzle 13 part Is provided with a heating element (not shown) that is turned on and off according to image information, and the end surface of the head body 11 exposed from the nozzle 13 is formed into a flat surface.
3 is coated with a liquid-repellent thin layer 14 for stabilizing the printing operation. On the other hand, the heat sink 12
Is a heat radiating plate that radiates the heat generated in the head body 11, and is assembled so that the end surface of the head body 11 exposed from the nozzle 13 is flush with one end surface of the heat sink 12.

Further, the maintenance device according to this embodiment has a vacuum nozzle 20. The vacuum nozzle 20 is arranged so as to face the inkjet head 10, and is arranged through the hole 23 a of the positioning guide 23. In this embodiment, the positioning guide 23 has a stepped recess 24 that holds the end portion of the ink jet head 10 on the ink ejection side.
In the inside, an appropriate number of guide rolls 25 that roll on contact with the end face of the ink jet head 10 on the ink ejection side and both side faces thereof.
When the vacuum nozzle 20 is moved and scanned along the arrangement direction of the nozzles 13 of the head main body 11, the positioning guide 23 causes the inkjet head 10 to move.
While holding the end portion of the ink discharge side of the head, it is constrained to move along the arrangement direction of the nozzles 13 so that the tip opening of the vacuum nozzle 20, that is, the suction opening 21 is arranged to face the nozzle 13 of the head body 11. It has become.

Further, the suction opening 21 according to this embodiment has an elliptical shape with a length of 0.2 mm in the arrangement direction of the nozzles 13 and a length of 1.0 mm in the direction perpendicular thereto, and projects into the recess 24 of the positioning guide 23. A nozzle guard 22 for protecting the surface of the nozzle 13 is provided around the tip of the vacuum nozzle 20. When the vacuum nozzle 20 is pressed against the inkjet head 10 by a pressure mechanism (not shown), a positioning guide 23 The end surface of the head body 11 and the nozzle guard 22 for protecting the nozzle surface are arranged in pressure contact with each other at a preferable pressure.

The material forming the vacuum nozzle 20 and the positioning guide 23 is not particularly limited, but it has water resistance and ink resistance, is easy to process, and slides smoothly on the ink jet head 10. Therefore, a material having a small friction coefficient is suitable, and for example, a fluorine-based resin such as Teflon, PES (polyethersulfone), an epoxy resin, or the like is used.

Further, the vacuum nozzle 20 is connected to a vacuum pump 27 through an ink trap section 26 having an atmospheric pressure of about 80 to 200 cmH ₂ O, and a suction opening 2 by negative pressure.
The ink 16 is drawn out from the nozzle 13 that faces the nozzle 1.

Next, the operation of the maintenance device according to this embodiment will be described. First, the inkjet head 10 is moved to the vicinity of the vacuum acting portion (maintenance stage), and the vacuum nozzle 20 is moved to the inkjet head 10.
Is pressed by. At this time, the vacuum nozzle 20 is located at the longitudinal end portion of the inkjet head 10, and the vacuum nozzle 20 is the nozzle 1 of the head body 11.
I'm not facing 3.

Next, the vacuum pump 27 is operated, and the suction operation is started from the vacuum nozzle 20 communicating with this vacuum pump 27. Thereafter, a moving scanning device (not shown) moves the vacuum nozzle 20 to 10 mm in the nozzle 13 array direction.
/ Sec. The suction opening 21 and the inkjet head 10 are moved relative to each other in the direction of the arrow at a speed of. By this movement, each nozzle 13 of the head main body 11 is sequentially sent to the suction opening 21 which is a negative pressure acting region of the vacuum nozzle 20. In particular, in this embodiment, the suction opening 21 of the vacuum nozzle 20 has a negative pressure acting on only one nozzle 13 which is directly opposed to the suction opening 21.
Only the ink 16 inside and outside is sucked, and the head body 1
Dust etc. on one end face is also sucked. After that, the sucked dust and ink are separated from the air flow by the ink trap portion 26 and collected in a waste liquid tank (not shown). After all the nozzles 13 have been subjected to the negative pressure action of the vacuum nozzles 20, the vacuum pump 27 and the moving scanning device of the vacuum nozzles 20 are stopped.

Next, FIG. 5 shows a specific example of the moving scanning device of the maintenance device according to this embodiment. In FIG.
The maintenance device according to this embodiment constitutes a maintenance station M together with a cap device 30 for preventing clogging due to drying of the nozzles 13 of the inkjet head 10. The maintenance device and the cap device 30 are the scanning carriage of the inkjet head 10. The carriages 31 are arranged in parallel along the moving direction of the scanning carriage (not shown), and are installed on the carriage 31 which can move back and forth in the horizontal front-rear direction orthogonal to the moving direction of the scanning carriage. When the printing operation for a predetermined time is completed,
It is designed to perform function recovery operations. In this embodiment, the positioning guide 23 is guided by a guide shaft 35 and a ball screw 36 so as to move up and down in the figure by the rotation of a motor 37. The vacuum nozzle 20 moves and scans following the movement of the positioning guide 23.

More specifically, in the function recovery operation, first, the ink jet head 10 is moved to a position directly facing the vacuum nozzle 20, and then the entire maintenance M is advanced to the ink jet head 10 side. The positioning guide 23 of 20 and the inkjet head 10 are butted. Next, the vacuum nozzle 20 is suctioned by the vacuum pump 27.
Are sequentially moved to face the nozzle 13 surface of the head body 11, and the maintenance operation described above is executed.

Example 2 FIGS. 6 to 7 show Example 2 of an inkjet head maintenance device to which the present invention is applied. The basic configuration of the maintenance device according to this embodiment is substantially the same as that of the first embodiment, but unlike the first embodiment, the vacuum nozzle 2 described above is used.
The front end portion of 0 is arranged flush with the bottom surface of the stepped recess 24 of the positioning guide 23, and the step portion 41 of the stepped recess 24 is disposed.
Of the vacuum head 20 contacts with the end surface of the ink jet head 10 on the ink ejection side, and the suction opening 21 of the vacuum nozzle 20 and the nozzle 13 of the head body 11 correspond to the height of the step 41.
A gap δ is secured between the surface and the surface.
Further, in this embodiment, the suction opening 21 has a rectangular shape having a length of 0.2 mm in the arrangement direction of the nozzles 13 and 1.0 mm in the direction orthogonal thereto, while the nozzles 13 of the positioning guide 23. The length dimension m along the arrangement direction is set to such an extent that several nozzle 13 regions are covered, as shown in FIG.
The bottom surface 42 of the recess 24 of 3 is 2 m around the suction opening 21.
It is flat about m and further has a circular arc portion 43 at its peripheral portion for reducing the resistance of the air flow. Further, in this embodiment, without using the guide roll 25 as in the first embodiment, the horizontal surface of the step portion 41 and the inner side surface of the embraced projecting piece 44 are located on both sides of the ink ejection side end surface of the inkjet head 10 and both sides thereof. The positioning guide 23 is slidably contacted with the surface, and is constrained to move along the nozzle 13 array direction of the inkjet head 10. In this case, the stepped portion 41 and the hugging protruding piece 44 are made of a material such as fluorine resin or epoxy resin having a low frictional resistance, and each corner portion is formed as an arc-shaped portion.

Next, the operation of the maintenance device according to this embodiment will be described. Basically, similar to the first embodiment, the vacuum nozzle 20 sucks the unnecessary ink 16 and the like inside and outside each nozzle 13 of the head body 11, but the difference in the suction area and the contact between the vacuum nozzle 20 and the head body 11 The following unique effects are achieved depending on the presence or absence of.
That is, when a negative pressure acts on the suction opening 21 of the vacuum nozzle 20, the nozzle 13 that faces the suction opening 21 directly.
A negative pressure acts on a and the nozzles 13b and 13c around it. Then, around the suction opening 21, the air flow 51 becomes parallel to the end surface of the head main body 11, and ink drops, outflowing ink, dust, etc. adhering to the end surface of the head main body 11 are sucked into the suction opening 2.
Suctioned to be swept up to 1. Then, as the vacuum nozzle 20 moves, the end surface of the head body 11 facing the suction opening 21 is wetted by the ink droplets drawn out from the nozzle 13, so that it is difficult to remove only by the air flow 51. The ink droplets are also united with the ink droplets on the end surface of the head body 11 and sucked. Similarly, dust and foreign matter 52 attached to the end surface of the head body 11 are also removed.
The sucked dust and ink are separated from the air flow by the ink trap section 26 and collected in a waste liquid tank (not shown).

Further, in this embodiment, since the vacuum nozzle 20 is not in contact with the area near the surface of the nozzle 13 of the head body 11, the thin liquid-repelling layer 14 on the end surface of the head body 11 may be worn unnecessarily. There is no such thing.

Incidentally, also in this embodiment, the maintenance station M as shown in FIG. 8 can be constructed. In the figure, the same components as those in the first embodiment are designated by the same reference numerals as those in the first embodiment, and the detailed description thereof is omitted here.

Third Embodiment FIGS. 9 to 11 show a third embodiment of an inkjet head maintenance device to which the present invention is applied. In this embodiment, a nozzle surface protection sheet (for example, made of PET [polyethylene terephthalate]) 60 having a thickness of 50 μm is arranged on the end surface of the head body 11, and the nozzle surface protection sheet 6 is provided.
The suction operation is performed by the vacuum nozzle 20 via 0. The nozzle surface protection sheet 60 has a length of 18.0 in the nozzle 13 array direction of the inkjet head 10.
mm, 1.0 mm wide slit 6 in the direction orthogonal to this
1 and the head body 1 is located in the slit 61 area.
Each nozzle 13 of No. 1 is arranged. Further, in this embodiment, the positioning guide 23 of the vacuum nozzle 20 has basically the same configuration as that of the first embodiment, but unlike the first embodiment, the nozzle surface protection sheet 60 is fixed in the positioning guide 23. When the vacuum nozzle 20 is not pressed, the nozzle surface protection sheet 60 is fixed by the tension of the head main body 11 of the inkjet head 10.
The nozzle surface is arranged with a constant gap. The slits 61 of the nozzle surface protection sheet 60 are provided on the positioning guide 23 according to this embodiment.
Slits 62 are formed along the longitudinal direction of the vacuum nozzle 20 so that the vacuum nozzle 20 independently forms the slit 6 of the positioning guide 23.
It is possible to move along 2 as well. Further, the vacuum nozzle 20 is arranged under pressure on the nozzle surface protection sheet 60 by a pressure mechanism (not shown) so as to extend across the width direction of the slit 61 of the nozzle surface protection sheet 60, as shown in FIG. , The nozzle surface protection sheet 60 near the vacuum nozzle 20 is the head body 11 nozzle 13
In this state, the vacuum nozzle 20 independently operates the nozzle 13 of the head body 11.
It is designed to move in the array direction.

Therefore, according to the maintenance apparatus of this embodiment, the nozzle surface protection sheet 60 is disposed on the end face of the ink jet head 10 on the ink ejection side, and the vacuum nozzle 20 is moved in the nozzle 13 array direction. The same maintenance operation as that of the first embodiment can be executed. At this time, since the nozzle surface protection sheet 60 does not slide on the end surface of the head body 11, friction does not work in the lateral direction around the nozzle 13 surface of the head body 11, and the end surface of the head body 11 does not move. It does not deteriorate the liquid repellent thin layer 14 and the like. Further, ink, dust, and the like attached to the entire end surface of the head body 11 are also pushed in the moving direction of the vacuum nozzle 20, held by the slit 61 of the nozzle surface protection sheet 60, and finally collected by the vacuum nozzle 20. In this state, the suction opening 21 of the vacuum nozzle 20 has the slit 6 of the nozzle surface protection sheet 60.
1, the air entrainment from the surroundings is significantly reduced due to the partitioning effect of the slit 61, as compared with the type of the second embodiment, so that the nozzles 13 of the head main body 11 are affected. The pressure drop is effectively suppressed.

Example 4 The basic structure of this example is substantially the same as that of Example 3, but
Unlike the third embodiment, as shown in FIG. 12, the solenoid valve 71 is adapted to give a certain fluctuation to the negative pressure introduced to the vacuum nozzle 20. Particularly, in this embodiment, the pressure sensor 72 is provided in the piping system between the vacuum nozzle 20 and the vacuum pump 27. First, when the user selects the cleaning mode selection switch 73, the control circuit 74 causes the vacuum pump 27 to operate. The output and the opening degree of the solenoid valve 71 are controlled to execute the clogging check operation. Pressure sensor 72 at this time
The clogging data generation circuit 75 generates the clogging data by detecting the pressure change. At this time, the control circuit 74 appropriately controls the suction operation of the vacuum nozzle 20 based on the clogging data. For example, when there is no clogging, but the image quality is not good, the vacuum pump 27 is set to a low output, the vacuum nozzle 20 is moved and scanned with the solenoid valve 71 open, and it is determined that clogging has occurred. In this case, for example, the vacuum pump 27 is set to a high output, the vacuum nozzle 20 is moved and scanned while the electromagnetic valve 71 is opened and closed (or the flow path diameter is changed), or
By turning on the vacuum pump 27 and opening and closing the solenoid valve 71 several times only in the vicinity of the specific nozzle 13 basin where the clogging occurs, it is possible to intensively supply the negative pressure to only the selective nozzle 13. Is. This reduces ink consumption,
With low power, it becomes possible to ensure the recovery operation of the function depending on the clogging status of the ink.

Modified Example In each of the embodiments, the vacuum nozzle 20 itself is basically moved, but the invention is not limited to this. For example, a plurality of vacuum nozzles are provided on the entire surface, and the flow with the vacuum pump is performed. By switching the path, the relative movement may be performed in a pseudo manner with respect to each nozzle 13 surface of the head body 11. Regarding the fluctuation of the negative pressure, by dividing the slit 61 of the nozzle surface protection sheet 60 without providing the solenoid valve 71 or the like, the intersection with the vacuum nozzle 20 (the cross-sectional area through which the negative pressure passes) is vacuumed. It may be configured to change with the movement of the nozzle 60. Furthermore,
As shown in FIG. 13, in the type having the head scanning mechanism of the rotary drum 80 type that holds the recording paper 81, the scanning direction of the inkjet head 10 and the arrangement direction of the nozzles 13 match, so the vacuum nozzle 20 is scanned. The same maintenance operation can be performed by moving the inkjet head 10 relative to the vacuum nozzle 20 without separately providing a mechanism for performing the same. It should be noted that FIG. 14 shows a printer having a plurality of heads 10a, 10b, 10c for multi-color recording.
By arranging c side by side along the scanning direction, it is possible to employ a maintenance device having the same configuration as in FIG.

[0030]

As described above, according to claims 1 to 3.
According to the invention described in any one of the above, since the nozzle body of the head main body is locally sucked and removed of ink or the like without wiping the end surface of the head main body by wiping, the head main body. There is no concern that the end surface of the nozzle will be unnecessarily worn, and a negative pressure drop due to ink suction from the peripheral nozzles can be avoided. Therefore, the unnecessary ink inside and outside the nozzle can be reliably removed with unnecessary minimum ink consumption without unnecessarily damaging the liquid treatment thin layer on the end surface of the head body, thereby preventing the nozzle clogging. It is possible to prevent clogging of the nozzle, to ensure the ejection stability of the inkjet head, and to reduce the capacity of the negative pressure generating means due to the small suction opening of the local suction means. Therefore, the inkjet recording apparatus can be downsized.

In particular, according to the second aspect of the invention, since the area near the nozzle surface of the head body and the local suction means are held in non-contact with each other, the liquid-repelling thin layer on the end surface of the head body is damaged. Not only can the situation be prevented more reliably and the life of the head can be extended, but even if it is used in a printer for multicolor recording, the ink adhering to the local suction means may mix with the ink on the head side. There is no.

Further, according to the third aspect of the present invention, since the negative pressure of the local suction means is changed, it is possible to surely recover the strong clogging with a low output, and also the ink clogging. If the negative pressure fluctuation is controlled according to the clogging state, the ink consumption amount can be suppressed to a necessary minimum.

[Brief description of drawings]

1A and 1B are explanatory views showing different configurations of a maintenance device for an inkjet head according to the present invention.

FIG. 2 is a perspective view showing an outline of a maintenance device according to the first embodiment.

FIG. 3 is a sectional view taken along line III-III in FIG.

FIG. 4 is an explanatory diagram showing the relationship between the nozzles of the head body and the vacuum nozzles of the first embodiment.

FIG. 5 is an explanatory diagram showing an example of a moving / scanning device of the inkjet head maintenance device according to the first embodiment.

FIG. 6 is a sectional view of the maintenance device according to the second embodiment, similar to FIG.

FIG. 7 is an explanatory diagram showing the relationship between the nozzles of the head body and the vacuum nozzles of the second embodiment.

FIG. 8 is an explanatory diagram illustrating an example of a moving scanning device of an inkjet head maintenance device according to a second embodiment.

FIG. 9 is a perspective view showing the outline of a maintenance device according to a third embodiment.

FIG. 10 is an explanatory diagram showing the relationship between the nozzles of the head body and vacuum nozzles of the third embodiment.

FIG. 11 is an explanatory diagram showing the relationship between the vacuum nozzle and the nozzle surface protection sheet of the third embodiment.

FIG. 12 is an explanatory diagram showing a configuration of an inkjet head maintenance device according to a fourth embodiment.

FIG. 13 is an explanatory diagram showing an example of a maintenance device of a rotary drum type head scanning mechanism type.

FIG. 14 is an explanatory diagram showing an example of a maintenance device of a rotary drum type head scanning mechanism type for multicolor recording.

FIG. 15 is an explanatory diagram showing an example of a conventional inkjet head maintenance device.

[Explanation of symbols]

1 ... Head body, 2 ... Nozzle, 3 ... Negative pressure generating means, 4 ...
Local suction means, 5 ... Suction opening, 6 ... Suction opening moving means, 7 ... Gap holding means, 8 ... Pressure fluctuation means

Claims (3)

[Claims] 1. A maintenance device for an ink jet head, wherein a plurality of nozzles (2) are formed in an array in a head body (1), and an end portion of the head body (1) is formed flat, and the maintenance device is lower than atmospheric pressure. Negative pressure generating means (3) for generating negative pressure and a size connected to the negative pressure generating means (3) so that the suction opening (5) faces the nozzle (2) region of one or several units. Local suction means (4) formed on
An ink jet head comprising a suction opening moving means (6) for relatively moving the suction opening (5) of the local suction means (4) in the direction of arrangement of the nozzles (2). Maintenance device. 2. A maintenance device for an ink jet head in which a large number of nozzles (2) are formed in an array in the head body (1) and the end portion of the head body (1) is formed flat, and the maintenance device is lower than atmospheric pressure. Negative pressure generating means (3) for generating negative pressure and a size connected to the negative pressure generating means (3) so that the suction opening (5) faces the nozzle (2) region of one or several units. Local suction means (4) formed on
Suction opening moving means (6) for relatively moving the suction opening (5) of the local suction means (4) toward the arrangement direction of the nozzles (2), and at least the local suction means (4) and the head. A maintenance device for an inkjet head, comprising: a gap holding means (7) for holding a space between the vicinity of the nozzle (2) surface of the main body (1) in a non-contact state. 3. The maintenance device for an ink jet head according to claim 1, further comprising a pressure fluctuation means (8) for changing the pressure generated by the negative pressure generation means (3).