JPH03227657A - Ink jet recording apparatus - Google Patents

Abstract

PURPOSE:To maintain the normal discharge of ink at all times thereby to assure recording of a high quality image by providing a cleaning means, at the side confronting to a recording head, for removing the substance adhered to the surface of a discharge port of the recording head and, using both driving of the recording head without discharge of ink and driving of an ultrasonic wave generating means so that the surface of the discharge port of the recording head is positively cleaned. CONSTITUTION:The ink is moved in a direction of an arrow P from a pump 5, and pushed out from each discharge port 37 of a recording head 1. While there is gathered a pack of ink 42 between the surface 9 of the discharge port of the recording head 1 and an ink collecting wall 40 of a cleaning means 39, the recording head 1 is driven without discharging ink. As a consequence of the blind discharging of the recording head 1, the ultrasonic pressure generated at an electro-thermal converting body 35 in each liquid passage 36 dissolves and removes an adhering substance 28 on the surface 9 through the pack of ink 42. The adhering substance 28 is washed away together with the collected ink 42. When driving of the recording head without discharge of ink is completed, the pack of ink 42 between the ink collecting wall 40 and discharge port surface 9 is collected down in a vertical direction in an ink absorbing body 41.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an inkjet recording apparatus, and particularly to an inkjet recording apparatus equipped with means for stably ejecting droplets from the ejection openings of a recording head.

[Prior Art] Recording devices such as printers, copiers, and facsimiles record images consisting of dot patterns on recording materials such as paper and thin brass plates based on transferred image information. It is configured.

The recording device may be an inkjet type,
It can be divided into wire dot type, thermal type, laser beam type, etc. Among them, inkjet type (inkjet recording device f) ejects droplets (small droplets of recording liquid or ink) from the ejection opening of the recording head, It is configured to attach this to a recording material and perform recording.

In this inkjet recording device, if ink liquid or foreign matter such as fixed ink or paper powder adheres to the ejection orifice surface of the recording head, ink ejection failure may occur due to unstable droplet ejection or clogging of the ejection orifices. Therefore, in order to eliminate the cause of this ejection failure and maintain normal and stable printing, ink ejection recovery means and ejection port surface cleaning means are provided.

FIG. 3 is a schematic diagram showing a schematic configuration of an inkjet recording apparatus suitable for applying the present invention.

First, with reference to FIG. 3, the ejection recovery means and ejection port surface cleaning means of a conventional inkjet recording apparatus will be described.

In FIG. 3, a capping means that can be joined to the discharge port surface 9 of the recording head l! 0, and during non-recording, the capping means 10 seals the ejection port surface 9 from the surrounding atmosphere, and brings the sealed space into a state of saturated vapor pressure of ink vapor. ) is intended to prevent the ink liquid from drying out and increasing its viscosity.

However, with these measures, in low-temperature environments or when recording is stopped for a long period of time, even if the above-mentioned capping is performed, it is not possible to completely prevent ink drying or increase in ink viscosity. Therefore, it has been difficult to completely eliminate ink ejection failure during recording.

In order to eliminate such inconvenience, as a means for preventing ejection failure of the recording head 1, the recording head 1 and the ink tank 4 are connected to each other.
Ink supply paths 6a and 6b capable of circulating ink are provided between the ink supply path 6a and an ink tank 5 as a pressurizing means, and the pump 5 is driven by a signal from the control section 8. A recovery means of circulating the ink 7 has been proposed.

In the illustrated example, each ink supply path 6a, 6b is connected at a midpoint with a connector 14a, 14b, and a filter 20a, 20b is provided inside each connector 14a, 14b.

In this way, by driving the pump 5, the ink from the ink tank 4 is pumped and circulated through the inside of the recording head l, and returned to the ink tank 4 again, and a part of the ink is discharged from all the ejection ports. A recovery device is configured.

Further, the illustrated inkjet recording apparatus is provided with an attached ink cleaning means for removing ink adhered to the ejection port surface 9 caused by ink ejected from the ejection port of the recording head l.

In the illustrated example, Lt, in response to a signal from the control unit 8, the conveying unit 25 of the capping unit IO is moved to a position where the ink absorber 21 provided in the capping unit IO comes into contact with the ejection opening surface 9 of the recording drum l. After one movement, the air pump 24
The compressed air from the capping means IO is supplied to the air blowing means 23, and the air blowing blows out the compressed air from the holes 22 toward the recording layer l, thereby removing the adhered ink on the ejection surface 9 of the recording head l. It is designed to blow off.

Note that the ink that has been blown off is removed by the capping means 10.
The ink absorber 21 provided inside the ink absorber 21 absorbs the ink.

Further, a configuration may be adopted in which the cleaning liquid is sprayed onto the discharge port surface 9 of the recording head 1.

By adopting such a configuration, ink ejection failure due to ink, paper dust, etc. adhering to the ejection port surface 9 of the recording head l is eliminated, and stable recording can be performed.

Here, the filters 20a and 20b provided in the middle of the ink supply paths 6a and 6b are used to prevent foreign matter from the ink cartridge 3, ink tank 4, pump 5, etc. from entering the liquid path of the recording head l during pressurized circulation of ink. This is to prevent the liquid from entering the interior and clogging the discharge port.

Therefore, usually the filters 20a, 20b are
A mesh S'(S>S') smaller than the cross-sectional area S of the ejection opening or liquid path of the recording head l is selected.

(Problem to be Solved by the Invention) However, even with the above-mentioned inkjet recording device, it is not possible to completely solve the adverse effects when the ejection port surface 9 of the recording head l is contaminated by ink adhesion. There wasn't.

4 and 5 are a side view and a front view, respectively, schematically showing the state when ink liquid, paper powder, dust, or other deposits adhere to the ejection port surface 9 of the recording head l. .

That is, even in the above conventional inkjet recording apparatus, as shown in FIGS. 4 and 5, minute ink mist 27 is generated when droplets 26 are ejected from each ejection port 37 of the recording head l. Or foreign matter such as paper powder may be present on the discharge port surface 9.
As a result, the ejection characteristics such as the amount of droplets ejected from each ejection port 37 of the recording head l, the ejection direction, and the ejection speed may change, and the There was a problem that the image quality deteriorated, such as the diameter of the recorded dots on the material being disturbed and uneven recording of 4 degrees.

The present invention has been made in view of such technical problems, and by reliably cleaning the ejection orifice surface of the recording head, normal ink ejection can be maintained at all times.
An object of the present invention is to provide an inkjet recording device that can record stable high-quality images.

[Means for solving problems]

The present invention provides cleaning means for removing deposits on the ejection port surface of the print head, separately from the conventional camping means, on the side facing the print head, and the ejection port surface of the print head is cleaned by the cleaning means. With the faces facing each other, ink is discharged from the ejection ports to form an ink pool, or cleaning liquid is supplied to form a cleaning liquid pool, and if necessary, the recording head is driven for idle ejection or the ultrasonic generating means is activated. The above objective is achieved by combining operations such as driving.

The invention of claim I provides an inkjet recording comprising: a recording head that performs recording by ejecting and flying ink droplets from an ejection port; an ink tank; and an ink supply path that supplies ink from the ink tank to the recording head. In the device,
An ink moving means for moving the ink in the ink supply path, and a cleaning means for cleaning the ejection orifice surface of the recording gutter, which is provided on the opposite side of the recording gutter, and cleaning the ejection orifice surface during non-printing. By idling the recording head while facing the cleaning means and moving the ink in the ink supply path by the ink moving means, the ejection orifice surface of the recording head can be reliably cleaned. It would be an advantage to provide an inkjet recording device that can be cleaned, can always maintain normal ink ejection, and can record stable high-quality images.

According to a second aspect of the invention, in addition to the configuration of claim 1, the ink in the ink supply path is moved after starting the idle ejection drive of the recording head, so that the ejection openings of the recording head are moved. An object of the present invention is to provide an inkjet recording device whose surface can be more reliably cleaned.

The invention according to claim 3 provides an inkjet recording apparatus that performs recording by ejecting and flying ink droplets from an ejection port of a recording head and making the droplets adhere to a recording material, in which the ejection port surface of the recording gutter and By arranging a cleaning means for cleaning the ejection port surface on the opposing side and providing an ultrasonic generation means in the cleaning means, the ejection port surface of the recording head can be reliably cleaned. An object of the present invention is to provide an inkjet recording apparatus that can always maintain normal ink ejection and record stable high-quality images.

In addition to the configuration of claim 3, the invention according to claim 4 provides, in addition to the configuration of claim 3, when the ejection port surface faces the cleaning means during non-recording,
By driving the ultrasonic wave generating means while communicating between the ejection orifice surface and the cleaning means by the ink ejected from the ejection orifice of the recording gutter, the ejection orifice surface of the recording head can be uniformly cleaned. 11. To provide an inkjet recording device that can be reliably cleaned.

In addition to the structure of claim 4, the invention of claim 5 provides, in addition to the recording head, at least an ink tank, an ink supply path for supplying ink from the ink tank to the recording head, and an ink supply path within the ink supply path. and an ink moving means for moving ink, and configured to drive the ink moving means when the ink discharged from the ejection ports of the recording head communicates between the ejection port surface and the cleaning means. This provides an inkjet recording apparatus that can more reliably clean the ejection port surface of the recording head.

In addition to the configuration of claim 4, the invention according to claim 6 provides a method of dryly ejecting a nozzle to the recording when the ink discharged from the ejection opening of the recording head communicates between the ejection opening surface and the cleaning means. By adopting a driving configuration, an inkjet recording apparatus is provided that can reliably clean the ejection orifice surface of the recording head.

The invention according to claim 7 provides an inkjet recording apparatus that performs recording by ejecting and flying ink droplets from the ejection openings of a recording head and making the droplets adhere to a recording material, in which an inkjet recording apparatus that performs recording by ejecting and flying ink droplets from the ejection openings of the recording head is provided. For example, by arranging a cleaning means for cleaning the ejection port surface, and providing the cleaning means with a cleaning liquid supply means for supplying a cleaning liquid to the ejection port surface and an ultrasonic wave generation means, recording can be performed. An object of the present invention is to provide an inkjet recording device that can reliably clean the ejection port surface of a head, maintain normal ink ejection at all times, and record stable high-quality images.

According to an eighth aspect of the invention, in addition to the configuration of claim 7, when the ejection port surface is faced to the cleaning means during non-recording,
By driving the ultrasonic wave generating means while communicating between the ejection opening surface and the cleaning means using the cleaning liquid supplied from the cleaning means, the ejection opening surface of the recording head can be cleaned more reliably. An object of the present invention is to provide an inkjet recording device that can be washed.

In addition to the structure of claim 8, the invention according to claim 9 provides, in addition to the recording head, at least an ink tank, an ink supply path for supplying ink from the ink tank to the recording head, and an ink supply path in the ink supply path. An ink moving means for moving ink is provided, and the ink moving means is driven when the cleaning liquid supplied from the cleaning means communicates between the ejection port surface and the cleaning means, An object of the present invention is to provide an inkjet recording apparatus that can more reliably clean the ejection port surface of a recording head.

In addition to the structure of claim 8, the invention of claim IO is a structure in which the recording head is driven to perform idle ejection so that the cleaning liquid supplied from the cleaning means communicates between the ejection port surface and the cleaning means. This provides an inkjet recording apparatus that can more reliably clean the ejection port surface of the recording head.

〔Example〕

Hereinafter, the present invention will be specifically explained with reference to the drawings.

In addition, in each drawing used for the following description, all the same or corresponding parts are indicated by the same code|symbol.

FIG. 1 is a perspective view showing the main parts of an inkjet recording apparatus according to the present invention.

In FIG. 1, numeral 12 is a platen roller driven by a motor (not shown) to convey a recording material such as paper or a thin plastic plate to form a recording surface.

Recording material in the form of continuous sheets or cut sheets (
(not shown) is given a conveyance force by a pinch roller (not shown) pressed against the platen roller 12, and the recording head l
and the platen roller 12.

The recording head (inkjet head) 1 is mounted on a carriage 2 that is driven reciprocally in the S direction in the figure along two guide rails 13a and 13b, and the ejection of the recording head 1 is caused by the reciprocating process. An image is recorded on the recording material by driving the energy generating body.

The carriage 2 is connected to a belt 19 stretched between a pulley 18a fixed to a shaft 17 of a motor 16 and an idle pulley 18b, and is moved along the platen roller 12 by driving the motor 16. Driven back and forth.

The illustrated recording head L is for color recording consisting of a plurality of recording units, for example, yellow (Y),
Magenta (M), Cyan (C), and Black (B)
It is composed of four recording units corresponding to four colors of ink.

Each recording unit for recording Y, M, C, and B has ink supply tubes 6aY, 6CM, 6aC, and 6aB.
are connected to the respective ink tanks 4Y, 4M, 4C and 4B, and each ink supply pipe 6aY, 6
There is a gear pump 5Y in the middle of CM, 6aC and 6aB.
5M, 5C and 5B are provided.

Therefore, each gear pump 5Y, 5M, 5C and 5B
By driving each ink tank 4Y, 4M, 4
Ink of each color within C and 4B is supplied to each recording unit.

In addition, each recording unit and each ink tank 4Y, 4M, 4
C and 4B are also connected by a return pipe that does not have a gear pump (for simplicity, only the return pipe 6bY that supplies yellow ink is shown).

Reference numeral 10 denotes a camping means disposed at the home position HP of the recording head l so as to be movable in the direction of the arrow r so as to face the ejection port surface 9 of the recording head l so as to press against and away from it.

Further, the ejection orifice surface 9 of the recording head l is cleaned at another position within the movement range of the recording head l, in the illustrated example, at an end position on the left side of the home position HP and adjacent to the capping means IO. A cleaning means 39 is provided for cleaning.

FIG. 2 is a partially cutaway perspective view showing the main structure of a recording head l suitable for use in an inkjet recording apparatus according to the present invention.

In FIG. 2, FIG. 4, and FIG.
29, a top plate 32, etc.

The electrothermal converter 35 and the electrode 34 are formed, for example, by a method of forming a film on the substrate 30 through a semiconductor manufacturing process such as etching, vapor deposition, or sputtering.

Recording ink 7 is supplied from the ink tank 4 (FIGS. 1 and 3) into the common liquid chamber 31 of the recording pad 1 through the ink supply pipe 6a.

33 in FIG. 2 indicates a supply port to which the ink supply pipe 6a is connected.

The ink 7 supplied into the common liquid chamber 31 is supplied into each liquid path 36 by capillary force, and is maintained in a stable state by forming a meniscus at the ejection opening 37 at the tip thereof.

By energizing the electrothermal converter 35, the liquid on the surface of the electrothermal converter is heated and a bubbling phenomenon occurs, and droplets are ejected from the ejection port 37 due to the energy of the foaming.

With the above configuration, 12-8 dots or 25
A multi-type 6-dot inkjet recording head can be obtained.

FIG. 6 is a schematic vertical sectional view showing a first embodiment of the cleaning means 39 (FIG. 1) of the inkjet recording apparatus according to the present invention together with the recording head l, and shows the ejection opening surface 9 of the recording head l. It shows the state when facing the person.

In FIG. 6, the cleaning means 39 has a structure in which an ink reservoir peripheral wall 40 and an ink absorber 41 disposed below the case 46 are housed in a case 46 that is open on the recording head l side.

This cleaning means 39 is disposed on the side facing the ejection port surface 9 of the recording head l, and when facing each other, a predetermined interval (for example, 0 A gap of .5+s) is formed.

The ink reservoir peripheral wall 40 can be made of, for example, plastic such as polyethylene or polypropylene, or metal such as stainless steel.

Further, the ink absorber 41 is made of an ink absorbing material such as a porous material.

In this embodiment, the cleaning means 39 and the ink moving means constituted by the ink pump 5 provided in the ink supply paths 6a and 6b (in the illustrated example, the ink supply path 6a side) cooperate with each other. At the time of recording, with the ejection opening surface 9 facing the cleaning means 39, the Rad I is driven to eject idly to the recording, and the ink in the ink supply paths 6a and 6b is moved by the ink moving means 5. It is configured to allow

That is, according to this embodiment, the pump 5 moves the ink in the ink supply paths 6a and 6b in the direction of the arrow P, and pushes out the ink from each ejection port 37 of the print head 1. While forming an ink reservoir 42 between the surface 9 and the ink reservoir peripheral wall 40 of the cleaning means 39,
The recording head I is controlled to be driven for idle ejection.

When the recording head l is driven to eject ink while pushing out ink from the ejection ports 37, bubbles 38 (Fig. 4) are formed and defoamed in the electrothermal converter 35 (Fig. 2) of each liquid path 36. The generated ultrasonic pressure dissolves and removes the deposits 28 that have adhered to and adhered to the ejection port surface 9 through the ink reservoir 42, and the deposits 28 are washed away vertically downward along with the ink reservoir 42. can.

After completing the idle ejection drive of the recording head l, the ink pool 42 between the ink pool peripheral wall 40 and the ejection port surface 9 is collected by the ink absorber 4 provided vertically below the ink pool IJ 40. Ru.

FIG. 7 is a graph showing the state of variation in recording density in the formation area of the ejection port 37 (recording width of the recording head 1). - The dashed line B represents the state when the discharge port surface 9 is contaminated.
Dashed lines C indicate the state after the discharge port surface 9 has been cleaned.

By cleaning the discharge port surface 9 with the cleaning means 39 explained in FIG. 6, the discharge port surface 9 is cleaned as shown in the graph of FIG.
The uneven recording density that occurs when the ejection port surface 9 is contaminated can be restored to the same state as before the ejection port surface 9 was contaminated.

Here, experimental results of the cleaning means 39 according to the present invention will be explained.

FIG. 8 is a timing chart of the pump drive time and the idle ejection drive time of the recording head.

The recording head 1 used had the structure shown in FIG. 2, had an ejection port density of 400 dpi, and had 256 ejection ports.

A water-based ink was used as the ink.

The distance between the ejection port surface 9 and the ink reservoir peripheral wall 40 is approximately 0.5-
It was set to

The amount of ink pushed out from each discharge port 37 by the pump 5 is 0.1=1. The drive time of the pump 5 is set to approximately 1 second at Occ/sec, and the idle discharge drive is as follows:
The maximum driving frequency f of the recording head 1 for all ejection ports of the recording head 1 is 2.

5kHz, voltage pulse width L applied during normal recording operation
The test was carried out at o*=l O, gec, and for an idle ejection drive time t, -about 5 seconds.

As a result, the recording density unevenness, which was about 0.2 degrees in density difference before cleaning the ejection port surface 9, could be restored to about 0.05 after cleaning.

FIG. 9 is a flowchart showing an example of the control operation of the embodiment described above.

In FIG. 9, when the power of the recording apparatus is turned on, the discharge port surface 9 of the recording drum L is capped by the capping means 10 (FIG. 1) in step S1, and step S2
At this time, it is determined whether or not to clean the ejection port surface 9 of the recording head l based on a signal from the control section 8 (FIG. 3).

When cleaning is performed, the capping of the recording head 1 is released in step S3, and the recording head is moved to the cleaning position in step S4, so that the ejection port surface 9 is aligned with the ink reservoir peripheral wall 40.
Stop at a position facing the

Next, in step S5, the pump 5 is driven to start extruding ink from each discharge port 37, and at the same time,
Dry ejection driving of the recording head l is started.

The discharge port surface 9 and the ink reservoir peripheral wall 40 of the cleaning means 39
An ink reservoir 42 is formed between the ink reservoir 42 and the idle ejection drive is performed for a predetermined period of time (several seconds) with the ink reservoir 42 formed, and then the drive of the pump 5 is ended in step S6, and then, in step S6, the drive of the pump 5 is terminated. In S7, the idle ejection drive of the recording head 1 is ended.

Next, in step S8, the recording head l is moved to the capping position (usually the home position HP), and in step S9
Then cap the rad l again for recording and enter the standby state.

On the other hand, if it is determined in step S2 that the cleaning operation of the recording head l is not performed, the process immediately enters a standby state.

In step S10, according to a signal from the control unit 8,
Determine whether to start recording.

When recording is to be performed, the process proceeds to step Sll, where the ink pump 5 (FIGS. 1 and 3) is driven to pressurize the ink in the ink supply tube 6a, and then, in step S12, the air pump 24 (see FIGS. The air blowing device 23 (see FIG. 3) blows air onto the ejection port surface 9 to clean the ink remaining on the ejection port surface 9.

Next, after canceling the capping in step S13,
Recording begins at step 514.

In step S15, it is determined whether recording has ended.

When the recording is completed, in step 316, the rad l is capped again for recording, and the apparatus enters a standby state.

Here, the signal instructing whether or not to perform the cleaning operation in step S2 is sent to the console 11 (
3) and issue a command to the control unit 8 to generate the signal.

Further, it is also possible to provide a counter that counts and stores the number of recording operations of the recording head L, and determine whether or not a cleaning operation is necessary based on this count value.
It is also possible to automatically control the cleaning operation so that the cleaning operation is carried out once every time.2 Figure 1θ shows a second embodiment of the cleaning means 39 (Figure 1) of the inkjet recording apparatus according to the present invention, together with the recording head l. 2 is a schematic vertical cross-sectional view showing the state when the discharge port face 9 of the recording head 1 is just faced.

FIG. 11 is a timing chart of the cleaning operation of the cleaning means 39 in FIG. 10.

In this embodiment, during the cleaning operation, the recording head l is moved to the cleaning position and the ejection port surface 9 and the ink reservoir peripheral wall 40 are
With the two facing each other, the ink pump 5 is controlled to first start the idle ejection drive of the rad l to the recording, and after a time ΔL (seconds) has elapsed, the ink pump 5 is driven.

In other words, the ejection port surface 9 faces the ink reservoir peripheral wall 40! By performing the idle ejection drive of the recording head l before the ink pump 5 pushes out the ink, the ink reservoir ejected from each ejection port 37 is deposited on the ink reservoir surrounding wall 40, as shown in FIG. The ink reservoir 42A is formed in advance by the ink reservoir 26.

After forming the ink reservoir 42A on the ink reservoir surrounding wall 40 in this way, the ink pump 5 is driven to push out ink from each ejection port 37. 42 can be formed more easily.

The other configuration of this embodiment is substantially the same as that of the first embodiment shown in FIG.

Here, experimental results regarding the time ΔL (seconds) between the start of the idle ejection operation of the recording head 1 and the start of driving the ink pump 5 will be described.

The second one has a discharge port density of 400 dpi and a number of discharge ports of 256.
Using a recording head l having the structure shown in the figure and water-based ink,
The gap between the discharge port surface 9 and the ink reservoir peripheral wall 40 is set to approximately 0.5 mm, and the amount of ink pushed out from each discharge port 37 by the pump 5 is set to approximately 0.5 mm. 2 CC/sec, and the maximum driving frequency f of the recording head l for all ejection ports of the recording head l,
, , = 2.5kl (z), and the idle ejection operation was performed with a voltage pulse width toe = l Oμsec applied during normal recording operation.

In that case, it was confirmed that the ink pool 42 between the ink pool peripheral wall 40 and the ejection port surface 9 is more likely to be formed when Δt=1 to 2 seconds than when Δ1=0 seconds. .

FIG. 12 is a timing chart showing a third embodiment of the cleaning operation of the recording head l of the ink shared recording apparatus according to the present invention.

In this embodiment, during the cleaning operation of the recording head 1, control is performed such that the idle ejection operation by the recording head 1 and the operation of pushing out ink from each ejection port 37 by driving the pump are repeated a plurality of times.

That is, as shown in FIG. 12, in one cleaning operation of the recording head l, each ejection port 37 is
Each ejection port 3 by idle ejection operation and ink pump drive
By repeating the ink extrusion operation from step 7 a plurality of times, it is possible to more reliably remove the deposits 28 firmly attached to the ejection port surface 9.

The other configurations of this embodiment are substantially the same as those of the previous embodiment.

Further, in this embodiment, the idle ejection driving time L□, L Hl"'-'- of the recording head l and the driving time [6, trz. =
Although it is set so that LM Lp+=Lez=tr, in order to improve the effect of removing deposits on the discharge port surface 9, the setting value of each numerical value can be rewritten from the console 11 (Fig. 3), etc., for example. With this configuration, the effects of this embodiment can be further improved.

In the first to third embodiments of the present invention described above, the ink reservoir surrounding wall 40 of the cleaning means 39 has been described as being made of a material such as plastic or metal that hardly absorbs ink. Any material can be used as long as it can form the ink reservoir peripheral wall 40 to a certain extent, and for example, even a porous plastic having a slow ink absorption rate can be used as the ink reservoir peripheral wall 40.

Furthermore, in each of the above embodiments, the ink supply path 6a,
Although the case where the pump 5 is provided in the ink supply paths 6a and 6b as means for moving the ink in the ink supply paths 6b has been described,
For example, a suction type ink moving means is used that sucks out ink from each ejection port 37 by creating a negative pressure in the atmosphere on the ejection port surface 9 of the lower recording head 1 with a pump or the like.
The effects of the present invention can also be fully achieved with such a suction type ink moving means.

FIG. 13 is a schematic vertical cross-sectional view showing a fourth embodiment of the cleaning means 39 (FIG. 1) of the ink side recording apparatus according to the present invention together with the recording head l, and shows the ejection orifice surface of the recording head l. It shows the state when facing 9.

In FIG. 13, the cleaning means 39 has an ink reservoir surrounding wall 40, an ink absorber 41 disposed below the ink reservoir surrounding wall 40, and an ink reservoir surrounding wall 40 that comes into contact with the ink reservoir surrounding wall 40, in a case 46 with the recording head l side open. The ultrasonic generating means 43 is housed therein.

For example, a piezoelectric element can be used as the ultrasonic wave generating means 43, and in the illustrated example, this piezoelectric element 43
is joined to the back surface of the ink reservoir peripheral wall 40.

This cleaning means 39 is disposed at a position facing the ejection port surface 9 of the recording head lO, and there is a predetermined interval (for example, 0.5 square meters) between the ink reservoir peripheral wall 40 and the ejection port surface 9. A gap is formed.

The ink reservoir peripheral wall 40 can be made of, for example, plastic such as polyethylene or polypropylene, or metal such as stainless steel.

Further, the ink absorber 41 is made of an ink absorbing material such as a porous material.

When cleaning the recording head l, first move the recording head l to a cleaning position where it faces the cleaning means 39, so that the ejection port surface 9 and the ink reservoir peripheral wall 40 face each other with a gap between them so that they do not come into contact with each other. .

Therefore, by moving the ink in the ink supply paths 6a and 6b in the direction of arrow P by the pump 5 and pushing out the ink from each discharge port 37, the discharge port surface 9 and the ink reservoir peripheral wall 4 are moved.
After that, an ink reservoir 42 communicating with the ultrasonic wave generating means 43 is formed in accordance with a command from the control section 8 via the electric wire A44.

That is, in this embodiment, the pressure waves generated from the ultrasonic generating means 43 are applied to the ejection port surface 9 via the ink reservoir peripheral wall 40 and the ink reservoir 42, thereby causing the ink to adhere to and adhere to the ejection port surface 9. The attached matter 28 is dissolved and removed using the ultrasonic cleaning effect, and the attached matter 28 is removed from the ink reservoir 4.
The ink cartridge 2 is flushed vertically downward and collected in an ink absorber 41 provided vertically below the ink reservoir peripheral wall 40.

By cleaning the ejection port surface 9 with the cleaning means 39 shown in FIG. can be restored to the same state as before it was contaminated.

Here, experimental results of the cleaning means 39 according to the present invention will be explained.

FIG. 14 shows the driving time of the pump 5 and the ultrasonic wave generating means 43.
3 is a timing chart showing the drive time of FIG.

The recording head I used had the structure shown in FIG. 2, had an ejection port density of 400 dpi, and had 256 ejection ports.

A water-based ink was used as the ink.

The distance between the ejection port surface 9 and the ink reservoir peripheral wall 40 formed of a stainless steel plate having a thickness of l- was set to about 0.5 mm.

The extrusion of ink from each ejection port 37 by the pump 5 is set at an ink extrusion amount of 0.1 to 1, Qcc/sec, and the drive time of the pump 5 is set to approximately 1 second, so that the extrusion of ink from the ejection port surface 9 is The sonic cleaning operation was performed by setting the driving conditions of the piezoelectric element as the ultrasonic wave generating means 43 to a frequency of 400 kHz and a driving time of about 3 seconds.

As a result, the recording density unevenness, which was about 0.2 degrees in density difference before cleaning the ejection port surface 9, could be restored to about 0.05 after cleaning.

FIG. 15 is a flowchart showing an example of the control operation of this embodiment.

In FIG. 15, when the power of the recording apparatus is turned on, the ejection port surface 9 of the recording drum L is capped by the gapping means 10 (FIG. 1) in step St, and step S
At step 2, it is determined based on the signal from the door section 8 (FIG. 3) whether or not the discharge port surface 9 of the recording drum 1 is to be cleaned.

When cleaning is performed, the capping of the recording head l is released in step S3, and the recording head is moved to the cleaning position in step S4, so that the ejection port surface 9 is aligned with the ink reservoir peripheral wall 40.
Stop at a position facing the

Next, in step S5, the pump 5 is driven to push out ink from each discharge port 37, and the ultrasonic generating means 43 is driven to perform ultrasonic cleaning of the discharge port surface 9 through the ink reservoir 42.

After performing ultrasonic cleaning for a predetermined time, the driving of the ink pump 5 is terminated in step S6, the driving of the ultrasonic generating means 43 is terminated in step S7, and then, in step S8, the recording head l is moved to the capping position (normally , home position H
P), and in step S9, the recording head 1 is capped again and enters a standby state.

On the other hand, if it is determined in step S2 that the cleaning operation of the recording pad 1 is not performed, the process immediately enters a standby state.

In the step SIO, it is determined based on a signal from the control unit 8 whether or not to start recording.

When recording is to be performed, the process proceeds to step Sll, where the ink pump 5 (FIGS. 1 and 3) is driven to pressurize the ink in the ink supply tube 6a, and then, in step S12, the air pump 24 (see FIGS. The air blowing device 23 (see FIG. 3) blows air onto the ejection port surface 9 to clean the ink remaining on the ejection port surface 9.

Next, after canceling the capping in step S13,
Recording is started in step S14.

In step S15, it is determined whether recording has ended or not.

When recording is completed, the recording head 1 is camped again in step S16 and enters a standby state.

Here, the signal instructing whether or not to perform the cleaning operation in step S2 is sent to the console 11 (
3) and issue a command to the control unit 8 to generate the signal.

Further, it is also possible to provide a counter that counts and stores the number of recording operations of the recording head l, and determine whether or not a cleaning operation is necessary based on this count value.
It is also possible to perform automatic control so that the cleaning operation is performed once every time.

FIG. 16 is a schematic vertical sectional view showing a fifth embodiment of the cleaning means 39 (FIG. 1) of the inkjet recording apparatus according to the present invention, together with the recording head 7, and the ejection opening of the recording head 1. This shows the state when facing surface 9.

FIG. 17 is a timing chart of the cleaning operation of the cleaning means 39 in FIG. 16.

In this embodiment, during the cleaning operation, the recording pad 1 is moved to the cleaning position, and the ejection port surface 9 and the ink reservoir peripheral wall 40 are moved to the cleaning position.
With the two faces facing each other, first, an idle ejection operation of the rad l to the recording is started, then after a time ΔL+ seconds has elapsed, the ink pump 5 is driven, and after 612 seconds have elapsed, the ultrasonic wave generating means 43 is driven. Do you want to control it? n will be done.

That is, at the position where the ejection port surface 9 faces the ink reservoir peripheral wall 4o, the rad 1 is driven to eject idly to the recording prior to the ink pump 5 pushing out the ink.
As shown in FIG. 16, control is performed so that an ink reservoir 42A is formed in advance on the ink reservoir peripheral wall 40 by the ink droplets 26 ejected from each ejection port 37.

For ink reservoir like this! After forming the ink reservoir 42A in the ink reservoir 140, the ink pump 5 is driven to push out ink from each discharge port 37, thereby making it easier to form the ink reservoir 42 that communicates the ink reservoir peripheral wall 40 with the discharge port surface 9. be able to.

The other configuration of this embodiment is substantially the same as that of the fourth embodiment shown in FIG. 13.

Here, the time 61. between the start of the above-mentioned idle ejection operation of the recording head l and the start of driving of the ink pump 5 and the ultrasonic wave generating means 43. Experimental results regarding seconds and 612 seconds will be explained.

The second one has a discharge port density of 400 dpi and a number of discharge ports of 256.
Using a recording head l having the structure shown in the figure and water-based ink,
The gap between the ejection port surface 9 and the ink reservoir peripheral wall 40 is set to about 0.5 mm, and the position at which ink is pushed out from each ejection port 37 by the pump 5 is set to about 0.5 mm. Set it to 2cc/sec and record the rad l.
The maximum driving frequency f of the recording head l for all ejection ports of
An idle ejection operation was performed at a frequency of 2.5 kHz and a voltage pulse width L oe of 104 sec, which is applied during a normal recording operation.

Further, a stainless steel plate having a thickness of 1 cm was used as the ink reservoir surrounding wall 40, and a piezoelectric element as the ultrasonic wave generating means 43 was driven at a frequency of 400 kHz.

As a result, the time Δt1 is better when ΔL+=about 1 to 2 seconds than when Δtl=0 seconds.
As L, ΔL! Δh=approximately 0.
5-1. It was confirmed that the ink pool 42 between the ink pool peripheral wall 40 and the ejection port surface 9 was more likely to be formed in the case of 5 seconds.

In each of the above embodiments, the ink reservoir peripheral wall 40 of the cleaning means 39 is made of plastic or metal.
In the above description, it is assumed that the material is a material that hardly absorbs the ink, but in reality, any material that can form the ink reservoir 42 to a certain extent may be used. It can be used as the peripheral wall 40.

FIG. 18 is a schematic vertical sectional view showing a sixth embodiment of the cleaning means 39 (FIG. 1) of the inkjet recording apparatus according to the present invention together with the recording head 1, in which the ejection port surface 9 of the recording head 1 and It shows the state when they met face to face.

In FIG. 18, the cleaning means 39 of this embodiment has a structure in which an ultrasonic wave generating means 43 made of an endless belt-shaped piezoelectric sheet and a belt cleaning member 47 are housed in a case 46 that is open on the recording head l side. It has become.

The endless belt-shaped piezoelectric sheet 43 is a member that forms an ink reservoir 42 facing the ejection port surface 9 of the recording head 1, and is made of, for example, a film sheet of PVdF or the like.

Further, an electrode 48 for applying a high frequency voltage is provided in contact with the belt-shaped piezoelectric sheet 43.

The belt-shaped piezoelectric sheet 43 is held between a roller 45a and a roller 45b in a state facing the discharge port surface 9,
If necessary, the rollers 45a, 45 may be moved by a motor (not shown) or the like.
It is supported so that it can be moved between the rollers 45a and 45b by rotating b.

When cleaning the ejection port surface 9 of the recording head 1, the ultrasonic wave generating means 43 is activated by driving the recording head l for idle ejection.
An ink reservoir 42 is formed between the belt-shaped piezoelectric sheet and the ejection port surface 9 of the recording head l, and then,
According to a command from the control unit 8, the electrode 4 is
By applying a high frequency voltage to 8 and mechanically vibrating the piezoelectric sheet 43 at high frequency, the discharge port surface 9 is ultrasonically cleaned.

After completing the cleaning operation of the recording head 1 in this way,
The piezoelectric sheet heald 43 is rotated by rotating the rollers 45a and 45b in the direction of the arrow by a motor (not shown) or the like.
is conveyed in the direction of the arrow, and the ink remaining on the piezoelectric sheet 43 is cleaned by the belt cleaning member 47.

By configuring the surface of the piezoelectric sheet 43 as a member forming the ink reservoir 42 to be cleaned at the end of the cleaning operation, when the next cleaning operation is performed, the surface of the piezoelectric sheet 43 that has been used in the previous cleaning operation is cleaned. The ink reservoir 42 can be formed without any deposits remaining, and the cleaning effect of the ejection port surface 9 can be further improved.

Note that in each of the above embodiments, the ink supply path 6a,
Although the case where the pump 5 is provided in the ink supply paths 6a and 6b as means for moving the ink in the ink supply paths 6b has been described,
For example, it is also possible to use a diversion type ink moving means that sucks out ink from each ejection port 37 by creating a negative pressure in the atmosphere on the ejection port surface 9 of the recording head l using a pump or the like. The effects of the present invention can also be fully achieved by a suction type ink moving means.

FIG. 19 is a schematic vertical sectional view showing a seventh embodiment of the cleaning means 39 (FIG. 1) of the inkjet recording apparatus according to the present invention together with the recording head l, in which the ejection opening surface 9 of the recording head l is shown. This shows the situation when facing the person.

In FIG. 19, the cleaning means 39 is placed in a case 46 that is open on the recording head l side, and includes a cleaning liquid reservoir peripheral wall 40, a waste liquid collection member 41 disposed below the peripheral wall 40, and abutting against the cleaning liquid reservoir wall 40. The ultrasonic wave generating means 43 is housed therein.

For example, a piezoelectric element can be used as the ultrasonic wave generating means 43, and in the illustrated example, this piezoelectric element 43
is joined to the back surface of the cleaning liquid reservoir peripheral wall 40.

This cleaning means 39 is disposed on the side of the recording head opposite to the discharge port surface 9, and a predetermined interval (for example, 0.5 square meters) is provided between the cleaning liquid reservoir peripheral wall 40 and the discharge port surface 9. A gap is formed.

The cleaning liquid reservoir peripheral wall 40 can be made of, for example, plastic such as polyethylene or polypropylene, or metal such as a stainless steel plate.

Further, the waste liquid collection member 41 is made of a porous material such as porous plastic.

When cleaning the recording head l, first, the recording head l is moved to a cleaning position facing the cleaning means 39, and the ejection port surface 9 and the cleaning liquid reservoir peripheral wall 40 are brought into a state where they face each other with a gap between them so that they do not come into contact with each other. .

Therefore, the cleaning liquid pump 51 is driven, and the cleaning liquid tank 5
The cleaning liquid in 2 is passed through the cleaning liquid supply path 53 to the discharge port 54.
The discharge port surface 9 of the drum 1 and the cleaning means 3
A cleaning liquid reservoir 4 communicates with the cleaning liquid reservoir peripheral wall 40 of 9.
2 is formed, and then, according to a command from the control unit 8, i
The ultrasonic generating means 43 is controlled to be driven via the power source 4.

That is, in this embodiment, by applying pressure waves generated from the ultrasonic generating means 43 to the discharge port surface 9 via the cleaning liquid reservoir peripheral wall 40 and the cleaning fluid reservoir 42, the pressure waves are applied to the discharge port surface 9 to avoid adhesion and adhesion to the discharge port surface 9. The deposits 28 that have been removed are dissolved and removed using the ultrasonic cleaning effect, and the deposits are removed from the cleaning solution reservoir 4 for 2 days.
The waste liquid is flushed vertically downward and collected in a waste liquid recovery member 41 provided vertically below the cleaning liquid reservoir peripheral wall 40.

By cleaning the ejection port surface 9 with the cleaning means 39 shown in FIG. 19, as shown in the graph of FIG. can be restored to the same state as before it was contaminated.

Here, experimental results of the cleaning means 39 according to the present invention will be explained.

FIG. 20 is a timing chart showing the driving time of the cleaning liquid pump 51 and the driving time of the ultrasonic wave generator 43.

As a recording head! A device having the structure shown in FIG. 2, with a discharge port density of 400 dpi, and a number of discharge ports of 256 was used.

A water-based ink was used as the cleaning liquid.

The distance between the discharge port surface 9 and the cleaning liquid reservoir peripheral wall 40 formed of a stainless steel plate with a thickness of l is approximately 0. It was set to 5tm.

The cleaning liquid is supplied by the cleaning liquid pump 51 at a flow rate of 0.
1=1. Occ/sec, the drive time 1C of the cleaning liquid pump 51 is set to about 1 second, and the ultrasonic cleaning operation of the discharge port surface 9 is performed by setting the drive condition of the piezoelectric element as the ultrasonic generating means 43 to a frequency of 400 kHz. In addition, the driving time 5 was set to approximately 3 seconds.

As a result, the recording density unevenness, which was about 0.2 degrees in density difference before cleaning the ejection port surface 9, could be restored to about 0.05 after cleaning.

FIG. 21 is a flowchart showing an example of the control operation of this embodiment.

In FIG. 21, when the power of the printing apparatus is turned on, the ejection port surface 9 of the printing head is capped by the camping means 10 (FIG. 1) in step S1, and step S1
At step 2, it is determined based on a signal from the control section 8 (FIG. 3) whether or not the ejection port surface 9 of the recording head l is to be cleaned.

If cleaning is to be performed, the capping of the recording head l- is released in step S3, and the recording head is moved to the cleaning position in step S4, so that the ejection port surface 9 is aligned with the cleaning liquid reservoir peripheral wall 4.
Stop at a position facing 0.

Next, in step S5, the cleaning liquid pump 51 is driven to push out the cleaning liquid from the discharge port 54, and the cleaning liquid is pushed out from the discharge port surface 9.
A cleaning liquid is filled between the cleaning liquid reservoir peripheral wall 40 and the cleaning liquid reservoir peripheral wall 40.

When the cleaning liquid is filled and the discharge port surface 9 and the cleaning liquid reservoir peripheral wall 40 are communicated through the cleaning liquid reservoir 42, in step S6, the cleaning liquid reservoir 42 is opened by driving the ultrasonic wave generating means 43.
Ultrasonic cleaning of the discharge port surface 9 is carried out through the discharge port surface 9.

After performing ultrasonic cleaning for a predetermined time, the driving of the cleaning liquid pump 51 is ended in step S7, the driving of the ultrasonic generating means 43 is ended in step S8, and then, in step S
Capping the recording head l at 9! (usually the home position HP), and in step SIO caps the rad l again for recording and enters a standby state.

On the other hand, if it is determined in step S2 that the cleaning operation of the recording head l is not performed, the process immediately enters a standby state.

In step Sll, it is determined based on a signal from the control section 8 whether or not to start recording.

When recording is to be performed, the process proceeds to step S12, where the ink pump 5 (FIGS. 1 and 3) is driven to pressurize the ink in the ink supply tube 6a, and then, in step S13, the air pump 24 (see FIGS. The air blowing device 23 (see FIG. 3) blows air onto the ejection port surface 9 to clean the ink remaining on the ejection port surface 9.

Next, after canceling the capping in step S14,
Recording is started in step S15.

In step 516, it is determined whether recording has ended.

When recording is completed, the recording head 1 is capped again in step S17 and enters a standby state.

Here, the signal instructing whether or not to perform the cleaning operation in step S2 is sent to the console 11 (
3) and issue a command to the control unit 8 to generate the signal.

Further, it is also possible to provide a counter that counts and stores the number of recording operations of the recording head l, and determine whether or not a cleaning operation is necessary based on this count value.
Is it automatic so that the cleaning operation is performed once every time? You can also do il.

FIG. 22 is a schematic longitudinal cross-sectional view showing an eighth embodiment of the cleaning means 39 (FIG. 1) of the ink side recording apparatus according to the present invention together with the recording head 1, and shows the ejection opening of the recording head L. This shows the state when facing surface 9.

FIG. 23 is a timing chart of the cleaning operation of the cleaning means 39 in FIG. 22.

In this embodiment, the recording head l is moved to the cleaning position so that the ejection port surface 9 and the cleaning liquid reservoir peripheral wall 40 face each other, and an ultrasonic cleaning operation similar to the cleaning operation in the embodiment shown in FIGS. 19 and 20 is performed. The ink pump 5 is configured to be driven when performing this.

The other parts of this embodiment have substantially the same structure as the case of FIG. 19, and corresponding parts are indicated by the same reference numerals, and their explanation will be omitted.

According to this embodiment, during ultrasonic cleaning of the ejection port surface 9 with cleaning liquid, the ink pump 5 is driven, and the ink supply path 6a,
By circulating the ink in the liquid path 6b under pressure in the direction of the arrow P and controlling the ink to be discharged from all the ejection ports 37 of the recording head l, the cleaning liquid infiltrates into the liquid path 36 and cleans the inside of the liquid path 36. It is possible to prevent problems such as changing the physical properties of the ink or foreign matter mixed in the cleaning liquid entering the liquid path 36, resulting in non-ejection of ink or deterioration of ejection characteristics.

That is, as shown in FIG. 23, the cleaning liquid pump 51
By continuing the operation of the ink pump 5 even after the operation of
It is controlled so that it does not mix into 6.

Here, the experimental results of the cleaning means 39 according to the embodiment shown in FIGS. 22 and 23 will be explained.

The recording pad 1 having the structure shown in FIG. 2 with a discharge port density of 400 dpj and a number of discharge ports of 256 is used, water-based ink is used as the recording ink, and the discharge port surface 9 and cleaning liquid reservoir peripheral wall 4-0 are connected to each other. The gap is set to about 0.5-, and a cleaning solution consisting of an aqueous solution of a neutral detergent is used as the cleaning solution.
Further, as the cleaning liquid pump 51 and the ink pump 5, those having a flow rate of about 1 cc/sec were used.

Therefore, the driving time t of the cleaning liquid pump 51 was set to about 1 second, the driving time 1 of the ultrasonic wave generator 43 was set to about 3 seconds, and the driving time tr of the ink pump 5 was set to about 3 seconds. It was also confirmed that the cleaning effect on the ejection port surface 9 of the recording head 1 was sufficient.

FIG. 24 is a schematic longitudinal cross-sectional view showing a ninth embodiment of the cleaning means 39 (FIG. 1) of the ink side recording apparatus according to the present invention together with the recording head 1, in which the cleaning means 39 (FIG. 1) is just discharged onto the recording head. The state when facing the exit surface 9 is shown.

FIG. 25 is a timing chart of the cleaning operation of the cleaning means 39 in FIG. 24.

In this embodiment, during the cleaning operation, the recording head river is moved to the cleaning position, and the discharge port surface 9 and the cleaning liquid reservoir river 940 are moved to the cleaning position.
- First, the recording head l starts an idle ejection operation, and then after a time Δ(1 second has elapsed), the cleaning liquid pump 51 is turned on, and after a time Δ[1 second has elapsed, an ultrasonic wave The generating means 43 are controlled to be driven respectively.

That is, at the position where the discharge port surface 9 faces the cleaning liquid reservoir circumferential wall 40, the rad 1 is idle-discharged to the recording area before the cleaning liquid pump 51 pushes out the cleaning liquid, so that the discharge is performed as shown in FIG. , the cleaning liquid reservoir peripheral wall 40 is controlled so that an ink reservoir 42A is formed in advance by the ink droplets 26 discharged from each discharge port 37.

After forming the ink pool 42A by the ejected ink droplets on the cleaning liquid reservoir peripheral wall 40 in this way, the ink pump 5
By driving the ink to push out the ink from each ejection port 37, the cleaning liquid reservoir 42 that communicates the cleaning liquid reservoir peripheral wall 40 and the ejection port surface 9 can be more easily formed.

The other configuration of this embodiment is substantially the same as that of the eighth embodiment shown in FIG. 22.

Here, the time 611 seconds and Δt! between the start of the idle discharge operation of the recording drum 1 described above and the start of driving the cleaning liquid pump 51 and the ultrasonic wave generating means 43, and Δt! Experimental results regarding seconds will be explained.

A recording head L having the structure shown in FIG. 2 with an ejection port density of 400 dpi and a number of ejection ports of 256 is used, water-based ink is used as the recording ink, and the gap between the ejection port surface 9 and the cleaning liquid reservoir peripheral wall 40 is Approximately 0. 5-, a cleaning liquid consisting of an aqueous solution of a neutral detergent is used, and the cleaning liquid pump 51 has a flow rate of about lee/second, and the cleaning liquid reservoir peripheral wall 40 is made of a stainless steel plate with a thickness of 1. used.

The conditions for the idle ejection operation of the recording head l are as follows: the maximum driving frequency of the recording head l is f, m = 2.5 h for all the ejection ports of the recording head l, and the voltage is applied during normal recording operation. Voltage pulse width [. , -10#sec was used for idle ejection.

Further, the piezoelectric element as the ultrasonic wave generating means 43 was driven at a frequency of 400kllz.

As a result, the time Δt1 is better when Δ[1=approximately 1 to 2 seconds than when ΔLr=0 seconds.
As Lg, Δ(2=approximately 0
．． 5-1. It was confirmed that the cleaning liquid pool 42 between the cleaning liquid pool peripheral wall 40 and the discharge port surface 9 was more likely to be formed in the case of 5 seconds.

In each of the above-mentioned embodiments, the cleaning liquid reservoir q! Although the description has been made assuming that the material 40 is made of a material such as plastic or metal that hardly absorbs cleaning liquid or ink, in reality, it may be made of any material that can form the cleaning liquid reservoir 42 to some extent, such as a type that absorbs cleaning liquid or ink at a slow rate. Porous plastic or the like can also be used as the cleaning liquid reservoir peripheral wall 40.

Further, in each of the above embodiments, the ink supply path 6a,
Although the case where the pump 5 is provided in the ink supply paths 6a and 6b as means for moving the ink in the ink supply paths 6b has been described,
For example, it is also possible to use a suction type ink moving means that sucks out ink from each ejection port 37 by creating a negative pressure in the atmosphere on the ejection port surface 9 under the recording spatula with a pump or the like. The effects of the present invention can also be sufficiently achieved by a suction type ink moving means.

[Effects of the Invention] As is clear from the above description, according to the present invention, a cleaning means for removing deposits on the ejection port surface of the print head is provided on the side facing the print head, and the ejection port surface of the print head is With the outlet surface facing the cleaning means, ink is discharged from the ejection port to form an ink pool, or cleaning liquid is supplied to form a cleaning liquid pool, and if necessary, the recording head is discharged dry. Since the configuration uses both drive and ultrasonic generator drive, the ejection orifice surface of the recording head can be reliably cleaned, and normal ink ejection is always maintained to produce stable, high-quality images. An inkjet recording device capable of recording is provided.

That is, according to the invention of claim 1, there is provided a recording head that performs one recording by ejecting and flying an ink liquid l from an ejection port;
An inkjet recording apparatus comprising an ink tank and an ink supply path that supplies ink from the ink tank to the recording head, an ink moving means for moving ink in the ink supply path, and an opposite side of the recording head. cleaning means for cleaning the ejection orifice surface of the recording head, and during non-printing, the recording head is driven for idle ejection with the ejection orifice surface facing the cleaning means, and the ink is Since the ink in the ink supply path is moved by the moving means, the ejection orifice surface of the print head can be reliably cleaned using pressure waves when the print head is driven, and normal ink ejection is always maintained. Provided is an inkjet recording device that can maintain high quality images and record stable high-quality images.

According to the invention of claim 2, in addition to the configuration of claim 1, the ink in the ink supply path is moved after starting the idle ejection drive of the recording head.
In addition to the above effects, an inkjet recording apparatus is provided that can more reliably clean the ejection port surface of the recording head.

According to the third aspect of the present invention, in the inkjet recording apparatus that performs recording by ejecting and flying ink droplets from the ejection opening of the recording head and making the twenty droplets adhere to the recording material, the ejection opening of the recording head A cleaning means for cleaning the ejection port surface is disposed on the side facing the surface, and an ultrasonic generating means is provided in the cleaning means, so that pressure waves from the ultrasonic generating means are used to clean the recording head. Provided is an inkjet recording device that can reliably clean the ejection port surface, maintain normal ink ejection at all times, and record stable high-quality images.

According to the invention of claim 4, in addition to the configuration of claim 3, the ejection is performed by the ink ejected from the ejection ports of the recording head with the ejection port surface facing the cleaning means during non-printing. Since the configuration is such that the ultrasonic generation means is driven while communicating between the outlet surface and the cleaning means, in addition to the above effects, the pressure waves from the ultrasonic generation means are transmitted to the ejection port surface via the ink reservoir. An inkjell recording apparatus is provided that can more reliably clean the ejection orifice surface of the recording head by applying the same amount of water.

According to the invention of claim 5, in addition to the configuration of claim 4, in addition to the recording head, at least an ink tank, an ink supply path for supplying ink from the ink tank to the recording head, and the ink supply path an ink moving means for moving the ink in the recording head, and a configuration for driving the ink moving means when the ink discharged from the ejection opening of the recording head communicates between the ejection opening surface and the cleaning means. Therefore, in addition to the above-mentioned effects, an inkjet recording apparatus is provided in which the ejection orifice surface of the recording head can be more reliably cleaned by applying pressure waves from the ultrasonic generating means to the ejection orifice surface via the ink reservoir. is provided.

According to the invention of claim 6, in addition to the configuration of claim 4, when the ink discharged from the ejection ports of the print head communicates between the ejection port surface and the cleaning means, the print head is emptied. Since the ejection is driven, in addition to the above effects, an ink pool can be formed more easily, and by applying pressure waves from the ultrasonic generating means to the ejection port surface via the ink pool, An inkjet recording apparatus is provided that can more reliably clean the ejection port surface of a recording head.

According to the seventh aspect of the present invention, in the inkjet recording apparatus that performs recording by ejecting and flying ink droplets from the ejection opening of the recording head and making the droplets adhere to the recording material, the ejection opening of the recording head A cleaning means for cleaning the discharge port surface is disposed on the side facing the discharge port surface, and the cleaning means is provided with a cleaning liquid supply means for supplying cleaning liquid to the discharge port surface and an ultrasonic generation means. By ultrasonic cleaning the ejection port surface of the recording head, the ejection port surface of the recording head can be reliably cleaned, and normal in- and reverse ejection can be maintained at all times, resulting in stable high quality. An inkjet recording device capable of recording images is provided.

According to the invention of claim 8, in addition to the configuration of claim 7, when the recording is not performed, the ejection port surface faces the cleaning means, and the cleaning liquid supplied from the cleaning means causes the ejection to be performed. Since the configuration is such that the ultrasonic generation means is driven while communicating between the outlet surface and the cleaning means, in addition to the above effects, the pressure waves from the ultrasonic generation means are transmitted to the discharge outlet surface through the cleaning liquid reservoir. An inkjet recording apparatus is provided in which the ejection port surface of the recording head can be more reliably cleaned by applying the same.

According to the invention of claim 9, in addition to the configuration of claim 8, in addition to the recording head, at least an ink tank, an ink supply path for supplying ink from the ink tank to the recording head, and the ink supply path and an ink moving means for moving the ink in the cleaning means, and the ink moving means is driven when the cleaning liquid supplied from the cleaning means communicates between the ejection port surface and the cleaning means. , it is possible to reliably prevent the cleaning liquid from mixing with the recording ink in the liquid path, and to apply pressure waves from the ultrasonic generation means to the ejection orifice surface through the cleaning liquid reservoir, thereby cleaning the ejection orifice surface of the recording head. -I! An inkjet recording device that can be conveniently cleaned is provided.

According to the invention of claim 10, in addition to the configuration of claim 8,
When the cleaning liquid supplied from the cleaning unit communicates between the ejection port surface and the cleaning unit, the recording head is driven to perform idle discharge, so that a cleaning liquid pool can be formed more easily. Furthermore, by applying pressure waves from the ultrasonic generating means to the ejection orifice surface via the cleaning liquid reservoir, an inkjet recording apparatus is provided that can more reliably clean the ejection orifice surface of the recording head.

[Brief explanation of drawings]

FIG. 1 is a perspective view schematically showing the main structure of an inkjet recording apparatus according to the present invention, FIG. 2 is a partially cutaway perspective view showing the main structure of the recording head in FIG. 1, and FIG. FIG. 4 is a schematic diagram showing the configuration of main parts of an inkjet recording apparatus suitable for carrying out the invention; FIG. 5 is a partial front view schematically showing the state of the ejection port surface of the recording head shown in FIG. 4, and FIG. 6 is a longitudinal sectional view schematically showing the first embodiment of the cleaning means for the inkjet recording apparatus according to the present invention. ,
FIG. 7 is a graph showing the unevenness of recording density in the recording width direction of the recording head depending on the presence or absence of cleaning operation, FIG. 8 is a timing chart of the cleaning operation of the cleaning means in FIG. 6, and FIG. 9 is the graph shown in FIG. 10 is a longitudinal sectional view schematically showing a second embodiment of the cleaning means of the inkjet recording apparatus according to the present invention, and FIG. 11 is a 1θ diagram of A timing chart of the cleaning operation of the cleaning means, FIG. 12 is a timing chart of the cleaning operation of the third embodiment of the cleaning means of the inkjet recording apparatus according to the present invention, and FIG. 13 is a timing chart of the cleaning operation of the fourth embodiment of the cleaning means of the inkjet recording apparatus according to the present invention. FIG. 4 is a timing chart of the cleaning operation of the cleaning means shown in FIG. 13; FIG. 15 is a flowchart showing the operation of the inkjet recording apparatus equipped with the cleaning means shown in FIG. 13; FIG. , FIG. 16 is a longitudinal cross-sectional view schematically showing a fifth embodiment of the cleaning means of an inkjet recording apparatus according to the present invention, FIG. 17 is a timing chart of the cleaning operation of the cleaning means of FIG. 16, and FIG. A vertical cross-sectional view schematically showing a sixth embodiment of the cleaning means for an inkjet recording apparatus according to the invention, i
19 is a longitudinal sectional view schematically showing a seventh embodiment of the cleaning means of an inkjet recording apparatus according to the present invention, FIG. 20 is a timing chart of the cleaning operation of the cleaning means of FIG. 19, and FIG. 21 is a diagram of the cleaning means of FIG. FIG. 22 is a longitudinal cross-sectional view schematically showing an eighth embodiment of the cleaning means of the inkjet recording apparatus according to the present invention, and FIG. A timing chart of the cleaning operation of the cleaning means, FIG. 24 is a vertical sectional view schematically showing a ninth embodiment of the cleaning means of the inkjet recording apparatus according to the present invention, and FIG. 25 is a timing chart of the cleaning operation of the cleaning means of FIG. 24. This is a timing chart. The symbols representing the main components in each drawing are listed below. l - recording head, 2 carriage, 4 ink tanks, = 5 - ink pump, 6 -, a, 6b ink supply path, 7 ink, 8 - control section, 9 ejection port surface,
10 Camping means, ll console, +
6--carriage motor, 26--ink droplet, 28
Deposit, 35 --- Electrothermal converter, 36- Liquid path,
37- Discharge port, 38 Air bubbles, 39 Cleaning means, 4
0--Ink reservoir surrounding wall, 42.42A-Ink reservoir, 43 Sardine sound wave generating means, 51-Washing liquid pump, 52-Washing liquid tank, 53-Washing liquid supply path, 5
4 Outlet.

Claims (10)

[Claims] (1) An inkjet recording apparatus comprising a recording head that performs recording by ejecting and flying ink droplets from an ejection port, an ink tank, and an ink supply path that supplies ink from the ink tank to the recording head. An ink moving means for moving the ink in the ink supply path, and a cleaning means for cleaning the ejection port surface of the print head, which is provided on the opposite side of the print head, and the cleaning device cleans the ejection port surface during non-printing. An inkjet recording apparatus, characterized in that the recording head is driven for idle ejection while facing the ink supply path, and the ink in the ink supply path is moved by the ink moving means. (2) The inkjet recording apparatus according to claim 1, wherein the ink within the ink supply path is moved after the idle ejection drive of the recording head is started. (3) In an inkjet recording apparatus that performs recording by ejecting and flying ink droplets from an ejection port of a print head and making the droplets adhere to a recording material, on the side facing the ejection port surface of the print head, An inkjet recording apparatus characterized in that a cleaning means for cleaning the ejection port surface is provided, and the cleaning means is provided with an ultrasonic generation means. (4) During non-printing, with the ejection orifice surface facing the cleaning means, the ejection orifice surface and the cleaning means are communicated with each other by ink discharged from the ejection orifices of the recording head; 4. The inkjet recording apparatus according to claim 3, further comprising driving an ultrasonic generating means. (5) In addition to the recording head, at least an ink tank,
It includes an ink supply path that supplies ink from the ink tank to the recording head, and an ink moving means that moves the ink in the ink supply path, and the ink discharged from the discharge port of the recording head is provided with an ink supply path that supplies ink to the recording head. 5. The ink jet recording apparatus according to claim 4, wherein the ink moving means is driven when communicating with the cleaning means. (6) The inkjet according to claim 4, characterized in that when the ink discharged from the ejection ports of the print head communicates between the ejection port surface and the cleaning means, the print head is driven for idle ejection. Recording device. (7) In an inkjet recording apparatus that performs recording by ejecting and flying ink droplets from an ejection port of a print head and making the droplets adhere to a recording material, on the side facing the ejection port surface of the print head, An inkjet recording apparatus characterized in that a cleaning means for cleaning the ejection orifice surface is disposed, and the cleaning means is provided with a cleaning liquid supply means for supplying a cleaning liquid to the ejection orifice surface and an ultrasonic generation means. (8) During non-recording, with the ejection port surface facing the cleaning means, the ultrasonic waves are 8. The inkjet recording apparatus according to claim 7, wherein the generating means is driven. (9) In addition to the recording head, at least an ink tank,
An ink supply path that supplies ink from the ink tank to the recording head, and an ink moving device that moves the ink in the ink supply path, and the cleaning liquid supplied from the cleaning device cleans the ejection port surface and the cleaning device. 9. The ink jet recording apparatus according to claim 8, wherein the ink moving means is driven when the ink moving means is communicated with the ink jet recording means. (10) The inkjet recording apparatus according to claim 8, wherein the recording head is driven to perform idle discharge when the cleaning liquid supplied from the cleaning unit communicates between the discharge port surface and the cleaning unit. .