JPH07205453A - Ink jet recorder and delivery recovery method - Google Patents

Abstract

PURPOSE:To keep an ink delivery performance of a recording head and extend the life thereof at a low cost without using a rubbing slide member for rubbing a delivery port surface and inducing the increase of a consumption amount of ink and the reduction of a throughput. CONSTITUTION:A delivery recovery operation comprises an ink removing process for removing ink in delivery ports 52 of a recording head 5, a heating process for heating the delivery ports 52 and thereabouts to a first set temperature, and an ink charging process for recharging ink in the delivery ports at the first set temperature, and a cooling process for cooling the delivery ports 52 and thereabouts to a second set temperature.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet recording apparatus for recording by ejecting ink from a recording means to a recording material, and an ejection recovery method for maintaining the ink ejection performance of the recording means.

[0002]

2. Description of the Related Art A recording device having functions such as a printer, a copying machine and a facsimile, or a recording device used as an output device of a multifunction machine or a workstation including a computer, a word processor, etc., is a sheet or a plastic thin plate based on image information. An image (including characters and symbols) is recorded on a recording material (recording medium) such as (OHP). The recording device can be classified into an ink jet type, a wire dot type, a heat sensitive type, a thermal transfer type, a laser beam type and the like depending on the recording system of the recording means used.

In a serial type recording apparatus which employs a recording system in which a main scanning is performed in a direction intersecting a conveying direction (sub-scanning direction) of a recording material, the recording material is set at a predetermined recording position and then the recording material is set. An image (including characters, symbols, etc.) is recorded by a recording unit (recording head) mounted on a carriage that moves (main scanning) along, and after one line of recording is completed, a predetermined amount of paper is fed (sub-scan). An image is recorded in a desired range of the recording material by repeating the operation of performing (scanning) and then recording (main scanning) the image of the next row. On the other hand, in a line type recording apparatus that records a recording material only in the sub-scanning direction in which the recording material is fed in the transport direction, the recording material is set at a predetermined recording position, and one line of recording is continuously performed at one time. A predetermined amount of paper feed (pitch feed) is performed, and an image is recorded on the entire recording material.

Among them, the ink jet type (ink jet recording apparatus) is a means for recording by ejecting ink from a recording means (recording head) onto a recording material, and it is easy to make the recording means compact and high definition. Images can be recorded at high speed, plain paper can be recorded without requiring special processing, running costs are low, and the non-impact method reduces noise and uses multicolor inks. Therefore, it has an advantage that it is easy to record a color image. Above all, a line type recording apparatus using a line type recording means in which a large number of ejection ports are arranged in the paper width direction can further speed up recording.

In particular, an ink jet type recording means (recording head) for ejecting ink by utilizing heat energy,
Through the semiconductor manufacturing process such as etching, vapor deposition, and sputtering, the electrothermal converter formed on the substrate, the electrode,
By forming the liquid passage wall, the top plate, and the like, it is possible to easily manufacture a liquid discharge device having a high-density liquid passage arrangement (ejection port arrangement), and to further reduce the size. Further, by utilizing the advantages of IC technology and micro processing technology, it is easy to make the recording means long and planar (two-dimensional), and it is also easy to make the recording means full-multi and high-density mounting. is there.

In the above ink jet recording apparatus,
Non-ejection or ejection of ink due to mixing of air into the recording unit (recording head), adhesion of paper powder, dust, thickened ink, etc., to the vicinity of the ejection port of the recording unit, or accumulation of ink near the ejection port. Discharge defects such as direction deviation may occur. Therefore, it is necessary to remove the foreign matter that causes the ejection failure, and to prevent such foreign matter from adhering or remove the adhering foreign matter to maintain the ink ejection performance of the inkjet recording unit. Means and methods are commonly referred to as ejection recovery means or methods.

Further, in the ink jet recording apparatus, for example, US Patent No. 4045082 and US Patent No. 4045082 are used to prevent ink thickening due to evaporation of the ink solvent or clogging of the discharge port due to dust adhesion or bubble generation. No. 4,069,31, a structure in which the ejection port surface of the recording head is covered with a cap and is shielded from the outside air to keep the ejection port in a good ink ejection state,
Alternatively, there is a configuration in which a discharge recovery device that discharges ink from a discharge port by a pump or the like is provided. Such capping operation (capping) and ejection recovery operation are usually performed when the carriage is at the home position.

In addition, foreign matter such as ink liquid, dust, dust, and paper dust may adhere to the vicinity of the ejection port of the recording head due to the recording operation, and a cleaning means for removing the foreign matter is provided. There is. As the cleaning means, there is used a cleaning means for wiping and cleaning the foreign matter by rubbing a blade formed of a rubber-like elastic body such as a plate-shaped urethane rubber against the ejection port surface. That is, as a cleaning means for removing ink and dust in the vicinity of the ejection port, first, US Pat.
As disclosed in No. 12435, U.S. Pat. No. 4,364065, or Japanese Patent Laid-Open No. 58-94472, there is a structure (hereinafter referred to as a first example) in which a discharge blade surface is wiped with a flexible blade such as rubber. Further, as this cleaning means, for example, other than this, for example, US Pat.
As described in No. 245, there is also a configuration in which a brush and an ink absorber are slid around the ejection port (hereinafter referred to as a prior art example 2).

[0009]

In the above-described prior art 1 and prior art 2, in some cases, ink droplets adhering to the periphery of the ejection port, or dew condensation around the ejection port caused by a rise in humidity in the device, etc. , It is possible to remove droplets having a relatively low viscosity. However, if you try to restart the recording after it has been paused or stopped for a long time,
The ejection recovery operation eliminates the occurrence of non-ejection, but the deviation in the ink flying direction is not eliminated, and the image may be disturbed because the ink droplet cannot be attached to the accurate position on the surface of the recording material.

The deviation in the ink flying direction is caused by the recording head 1 as shown in the side view (a) and the front view (b) of FIG.
No. 5 shows a very thin fixed state of the coating ID with low ink repellency formed in the vicinity of the ejection port, and in the case of using the prior example 1, the side view (a) and the front view (b) of FIG. As shown in the experiment by the inventors, it is apparent that the ink droplet ejection direction is bent by the ink thickening substance Id adhering to the downstream end of the ejection port in the wiping direction (rubbing direction). became. Therefore, the inventors have already proposed a method of satisfactorily removing the above-mentioned adhered film and adhered matter by pressingly sliding the ejection outlet surface with a sliding member other than the blade at a predetermined timing.

As described above, the method of removing the adhered coating film or the adhered matter that causes the ejection failure by sliding the ejection opening surface under pressure contact with the sliding member other than the blade at a predetermined timing is the ejection of the recording head. It is possible to realize a long life while maintaining the characteristics, and it is an important technology especially in the permanent type recording head.

However, in the conventional ink jet recording apparatus having such a rubbing member, ink or dust accumulated on the rubbing member is re-adhered to the recording head during the rubbing operation, resulting in non-ejection or twisting. One recording head of different colors is used, such as a color inkjet recording apparatus that uses a plurality of recording heads that raise or eject different colors of ink.
In the case of rubbing with one rubbing member, problems such as mixing of different color inks (color mixing) may occur, so it is necessary to perform recovery operation such as suction recovery operation again after rubbing operation. However, there is an inconvenience that the ink consumption increases and the throughput decreases. That is, in the prior art, an inkjet recording apparatus and an ejection recovery method that can meet the demand for achieving a long life while maintaining the ejection characteristics of the recording head at low cost without increasing the ink consumption amount and decreasing the throughput. Did not exist.

The present invention has been made in view of the above-mentioned prior art, and an object of the present invention is to use a rubbing member at a low cost, without increasing an ink consumption amount and reducing a throughput. It is an object of the present invention to provide an inkjet recording apparatus and an ejection recovery method capable of extending the life of the recording unit while maintaining the ink ejection performance of the recording unit.

[0014]

According to a first aspect of the present invention, in an ink jet recording apparatus for recording by ejecting ink from a recording means onto a recording material, an ink removing means for removing ink in an ejection port of the recording means, An ink removing step of removing ink in the ejection port of the recording unit, comprising a heating unit for heating the vicinity of the ejection port and a cooling unit for cooling the vicinity of the ejection port;
A heating step of heating the vicinity of the ejection port to a first set temperature, an ink filling step of refilling the inside of the ejection port with ink under the first set temperature, and a second set temperature near the ejection port. The above-described object is achieved by adopting a configuration for performing the discharge recovery operation including a cooling step of cooling.

According to a second aspect of the present invention, in addition to the structure of the first aspect, there is provided a wiping member for wiping and cleaning the ejection port surface, and the ejection recovery operation is performed under the first set temperature. The above object can be achieved more efficiently by including a wiping step of wiping the discharge port surface once or more with a member.

According to a fifth aspect of the invention, in an ejection recovery method for maintaining the ink ejection performance of the recording means, an ink removing step of removing ink in the ejection openings of the recording means and heating the vicinity of the ejection openings to a first set temperature. The heating step, the ink filling step of refilling the ink into the ejection port under the first set temperature, and the cooling step of cooling the vicinity of the ejection port to the second set temperature. Thus, the above object is achieved.

According to a sixth aspect of the present invention, in addition to the configuration of the fifth aspect, it includes a wiping step of wiping the ejection opening face of the recording unit with the wiping member at least once under the first set temperature. By doing so, the above object can be achieved more efficiently.

[0018]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic plan view showing a main part of an ink jet recording apparatus suitable for applying the present invention. In FIG. 1, a guide shaft 3 is installed in front of a recording material 2 such as paper or a plastic thin plate backed up by a platen 1, and a recording head (recording means) is attached to a carriage 4 which moves along the guide shaft 3. 5 is installed.

Various types of recording heads can be used as the recording head 5, for example, a recording unit which is composed only of an ink tank and a separate recording unit, and a replaceable cartridge type which is integrated with the ink tank. Further, it may be a line type having a length that covers the entire area or a part of the recording material 2 in the width direction. Further, the inkjet recording apparatus of FIG. 1 is for monochromatic recording using one recording head 5, but this is an inkjet recording apparatus using a plurality of recording heads such as for color recording and gradation recording. May be

The recording head 5 is an ink jet recording means for ejecting ink by utilizing heat energy, and is provided with an electrothermal converter for generating heat energy. The recording head 5 performs recording by ejecting ink from an ejection port by utilizing a pressure change caused by growth and contraction of bubbles due to film boiling caused by thermal energy applied by the electrothermal converter. Is.

FIG. 2 is a partial perspective view schematically showing the structure of the ink ejection portion of the recording means (recording head) 5.
In FIG. 2, the ejection port surface 5 that faces the recording material 2 with a predetermined gap (for example, about 0.5 to 2.0 mm).
1, a plurality of discharge ports 52 are formed at a predetermined pitch,
An electrothermal converter (a heating resistor or the like) 55 for generating energy for ejecting ink is disposed along the wall surface of each liquid passage 54 that connects the common liquid chamber 53 and each ejection port 52.

In this example, the recording head 5 is mounted on the carriage 4 in such a positional relationship that the ejection ports 52 are arranged in a direction intersecting the scanning direction of the carriage 4. In this manner, the corresponding electrothermal converter 55 is driven (energized) based on the image signal or the ejection signal to cause the ink in the liquid path 54 to film-boil, and the pressure generated at that time causes the ink to be ejected from the ejection port 52. The recording head 5 is configured. Further, in the vicinity of the ejection port 52 of the recording head 5, an electrothermal converter (so-called sub-heater) 56 for keeping the recording head 5 warm is provided in addition to the electrothermal converter 55 for ejecting ink. ing.

In FIG. 1, at the home position HP of the carriage 4, an ejection recovery device 6 (pump suction type in the illustrated example) of the recording head 5 is arranged. FIG. 3 is a schematic perspective view of the discharge recovery device 6. In FIG. 1 and FIG. 3, the ejection recovery device 6 is arranged so as to be able to move forward and backward with respect to the recording head 5, and is provided with a capping means 7 and a suction pump 9. The capping means 7
Is provided with a cap 17 that is in close contact with the ejection port surface 51 of the recording head 5 at the forward position and seals the ejection port 52. The suction pump 9 is for sucking ink from the ejection port 52 of the recording head 5 through the capping means 7. The operation of the discharge recovery device 6 is performed automatically, but can also be performed by a switch operation of the user.

1 and 3, the discharge recovery device 6
An elastic blade 10 for wiping the vicinity of the ejection port of the recording head 5 (usually the ejection port surface) is provided on the side of
Is installed. Further, in the illustrated inkjet recording apparatus, a rubbing member 11 is provided on the side of the capping means 7 so as to move forward and backward integrally with the capping means. The rubbing member 11 is a member that rubs the vicinity of the ejection port 52 (ejection port surface 51) of the recording head 5 and presses and slides on the ejection port surface 51 with a contact area larger than that of the elastic blade 10. Is configured. However, by applying the present invention, the rubbing member 11 can be deleted.

FIG. 4A is a partially enlarged perspective view showing a wiping (cleaning) operation by the elastic blade 10, and FIG. 4B is a state in which the rubbing member 11 is brought into pressure contact sliding (cleaning). It is a partial expansion perspective view shown for reference. In this type of inkjet recording apparatus, by controlling the movement of the carriage 4, when the recording head 5 comes off the home position HP in FIG. ) 11 is moved forward to bring the rubbing member 11 into pressure contact with the discharge port surface 51 as shown in FIG. 4B, and the carriage 4 is further moved to the right in FIG. The rubbing member 11 can rub (rub) the ejection port surface 51. That is, the rubbing operation by the rubbing member 11 can be performed by using the capping operation and the carriage operation.

The rubbing member 11 is for rubbing the adhered film-thickened ink thickened material without damaging the ejection port surface 51 of the recording head 5, and is, for example, a porous body, a fibrous structure, or the like. It is made of non-woven fabric. Further, in general, the rubbing operation of the rubbing member (rubbing member) 11 is performed every predetermined operation of the recording apparatus. The predetermined operation of the recording device is performed at a timing before the ejection failure is actualized or at a timing at which the peeling strength of the ink film Id (FIG. 9) that causes the ejection failure can be prevented in advance. Is selected. Further, the rubbing operation of the rubbing member 11 is performed at a timing at which the ink ejection can be stabilized without the user's awareness, that is, when the ink tank is replaced, a set time managed by a timer, and when the power is turned on. And so on.

Next, with reference to the ink jet recording apparatus described above, the recording means (recording head) 5 according to the present invention.
The principle of the discharge recovery operation will be described. The present invention relates to an inkjet recording apparatus that executes an ejection recovery operation described in detail below and a method of executing the ejection recovery operation. The inventors of the present invention have made the foreign matter in the vicinity of the ejection port 52 that causes the deviation in the ink flying direction as described above, that is,
As a result of diligent examination of a method of removing a film having a low ink repellency in an extremely thin fixed state formed in the vicinity of the ejection port 52 or a thickened material of the ink, the result is not due to mechanical rubbing force as in the prior art. It was found that the adhered matter can be removed by heating the vicinity of the ejection port 52 in the absence of ink and refilling the ink in the heated state. The mechanism for removing the deposit is considered as follows.

That is, the adherent is mainly an ink composition and originally soluble in the ink, but since it grows by repeating heating and drying and deposition when ejecting the recording ink, it is bonded by a chemical reaction at the adherent interface, High-density deposition occurs on the top. Therefore, only by immersing the deposit in the ink, the dissolution rate is very small and it is not a practical removal method.

Further, when the ink is heated in the state where the ink is present in the ejection port 52, it is difficult to break the bond at the adhesion interface and heat the adhered material to a temperature at which a practical dissolution rate is obtained. Therefore, in the ejection recovery method of the present invention, after the ink in the ejection port 52 of the recording head 5 is removed, the ejection port 5 is removed.
2 near the first set temperature, then the first
The ink is refilled in the ejection port 52 under the set temperature of
After that, a step of cooling the vicinity of the discharge port 52 to the second set temperature is adopted.

That is, as in the present invention, the discharge port 52 once
If you heat after removing more ink, you can easily heat the deposit to a higher temperature in a short time,
When the ink is refilled in this state, the deposit can be easily dissolved in the ink separated from the interface and can be easily removed together with the ink.

The present invention has been completed by experimentally confirming and analyzing such an event. Further, the present invention is effective as a general deposit removing means regardless of the mechanism described above. Furthermore, the present invention is effective not only in monochromatic recording but also in multicolor recording such as color recording or monocolor recording.

FIG. 5 is a flow chart showing a first embodiment of the discharge recovery operation to which the present invention is applied. In FIG.
When a command for a discharge recovery operation is sent to the apparatus body manually or automatically, recording is interrupted, the carriage 4 is returned to the home position HP, and stopped there (step S
1). Next, the recording heater 55 is driven with a pulse width and high frequency shorter than usual so that ink is not ejected (step S2), and the vicinity of the heater 55 (the vicinity of the ejection port 52) is heated. In this short pulse high frequency driving, since ink is not ejected, heating is effectively performed, the ink in the vicinity of the heater 55 reaches a high temperature in a short time, and air bubbles in the ink grow, so that the ink inside the ejection port 52 is ejected. The ink projects from the ejection port 52. The driving time of the recording heater 55 is managed by the time T1 (step S3).

When the drive time T1 has elapsed, the ejection port surface 51 is wiped by the elastic blade 10 (step S4). That is, when the wiping operation is performed in the above state, the ink is removed from the ejection port 52, the ejection port 52 communicates with the atmosphere, and the residual ink is removed from the recording head 5 by the negative pressure of the ink supply system. By this step, the ink is not supplied again to the ejection port 52, and the ink removal is completed. In the above steps, the time from the short pulse high frequency driving to the start of ink ejection becomes longer as the number of bubbles in the ink is smaller. Therefore, the driving time T1 is set to match the ink ejection time in the bubble-free state. Is set.

After wiping the ejection port surface 51 with the elastic blade 10, the short pulse high frequency driving of the recording heater 55 is stopped (step S5), and the driving of the sub heater 56 (FIG. 2) is started (step S5). S6). Unlike the discharge heater 55, the sub-heater 56 can be used for a long period of time without considering the life of the surface, so that the vicinity of the discharge port 52 can be heated to a temperature at which deposits can be removed. The driving time of the sub heater 56 in this case is managed by the time T2 (step S7).

Ink is filled in the recording head 5 by performing suction recovery while being sufficiently heated by driving the sub heater 56 for time T2 or more (step S
8). Then, as described above, the deposits in the vicinity of the ejection port 52 are removed, and the image defect such as the deviation of the ink ejection is eliminated. During this step, the time T2 from the driving start of the sub-heater 56 to the suction recovery start varies depending on the ink composition used and the material of the ejection port surface 51, and is experimentally obtained.
After the suction recovery, the sub heater 56 is stopped (step S
9) Then, the standby operation for cooling the recording head 5 is started (step S10), and after waiting for a predetermined time T3 (step S11), the standby operation is released (step S).
12) The state becomes READY.

According to the discharge recovery operation (discharge recovery method) according to the sequence shown in FIG. 5, the sliding member 1 is
Inkjet that can achieve a long life of the recording head 5 while maintaining the ink ejection performance of the recording head 5 at a low cost without increasing the ink consumption amount and decreasing the throughput without using 1. A recording device and a discharge recovery method are provided.

FIG. 6 is a flow chart showing a second embodiment of the discharge recovery operation to which the present invention is applied. In FIG.
When a command for a discharge recovery operation is sent to the apparatus body manually or automatically, recording is interrupted, the carriage 4 is returned to the home position HP, and stopped there (step S
31). Next, the cap 17 is brought into close contact with the ejection port surface 51 of the recording head 5 to seal the ejection port 52 (step S3).
2) After that, the cap 17 is further pressed toward the ejection port surface 51 (step S33). By this operation, the ink in the ejection port 52 (in the liquid path 54) is pushed back by the air in the cap 17, and the ink removal from the ejection port 52 is completed.

In this state, the driving of the sub-heater 56 is started (step S34), and the vicinity of the discharge port 52 is heated to the temperature D1 at which the deposit can be removed (step S35). This time,
The heating by the sub-heater 56 is continued until the value detected by the recording head temperature detector provided in the vicinity of the ejection port 52 reaches the temperature D1 required for removing adhered substances, which is experimentally determined. In the fully heated state, the inside of the cap 17 is opened to the atmosphere to fill the ink in the ejection port 52 (step S36). Then, as described above, the deposits in the vicinity of the ejection port 52 are removed, and the image defect such as the deviation of the ink ejection is eliminated. After opening the cap 17 to the atmosphere, the sub-heater 56 is stopped (step S3
7) The standby operation for cooling the recording head 5 is started (step S38). By this standby operation, the recording head 5
When the temperature detection value of is less than or equal to D2 (step S39),
The standby operation is canceled (step S40). After the standby operation is released, the state becomes READY.

According to the discharge recovery operation (discharge recovery method) according to the sequence described above with reference to FIG. 6, the rubbing member 11 is not used as in the case of the first embodiment described above.
At a low cost, the ink ejection performance of the recording head 5 can be maintained, the life of the recording head 5 can be extended, and the ambient conditions such as environmental temperature can be increased without increasing the ink consumption amount and the throughput. There is provided an inkjet recording apparatus and an ejection recovery method capable of performing a recovery operation of a recording head 5 in a stable and reliable manner in a short time without being affected by the above.

FIG. 7 is a flow chart showing the third embodiment of the discharge recovery operation to which the present invention is applied. In FIG.
When a command for a discharge recovery operation is sent to the apparatus body manually or automatically, recording is interrupted, the carriage 4 is returned to the home position HP, and stopped there (step S
51). Hereinafter, as in the case of the above-described first embodiment, the recording heater 55 is driven for a predetermined time with a pulse width and a high frequency shorter than usual so that ink is not ejected (step S5).
2, S53), the vicinity of the heater 55 (the vicinity of the ejection port 52) is heated, and the ejection port surface 51 is wiped with the ink protruding from the ejection port 52 (step S54). Complete the removal of.

After the ejection port surface 51 is wiped by the elastic blade 10, the short pulse high frequency driving of the recording heater 55 is stopped (step S), and the driving of the sub heater 56 is started (step S56). By controlling the driving time of the sub-heater 56 to T2 or more, the vicinity of the discharge port 52 is heated to a temperature at which the deposit can be removed (step S57). In this sufficiently heated state, the ejection port surface 51 is wiped again by the elastic blade 10 (step S58), and then suction recovery is performed to fill the recording head 5 with ink (step S59). ).
By performing the wiping in the heating state as described above, the exfoliation of the adhering substances on the ejection port surface 51 is promoted, and the effective adhering substances can be removed. After the suction recovery, the sub-heater 56 is stopped (step S60), a standby operation for cooling the recording head 5 is started (step S61), and after waiting for a predetermined time T3 (step S62), the standby operation is released (step S63). ), The state becomes READY.

According to the discharge recovery operation (discharge recovery method) according to the sequence described above with reference to FIG. 7, the rubbing member 11 is not used as in the case of the first embodiment.
At a low cost, the ink ejection performance of the recording head 5 can be maintained and the life of the recording head 5 can be extended without increasing the ink consumption amount and the throughput, and in addition, wiping (wiping) in a heated state can be achieved. ) An ink jet recording apparatus and an ejection recovery method capable of setting a required heating temperature low by improving the effect, capable of performing an effective ejection recovery operation of a recording head at a higher speed with a lower cost configuration are provided. It

That is, according to each of the above embodiments, means for removing the ink inside the ink discharge port of the recording head,
A step of removing ink inside the ink ejection port of the recording head 5 in an inkjet recording apparatus having means for heating the vicinity of the ejection port and means for cooling the vicinity of the ejection port;
Heating the vicinity of the discharge port to a first set temperature;
Since the ejection recovery operation is performed including the step of refilling the ejection port with ink under the preset temperature and the step of cooling the vicinity of the ejection port to the second preset temperature, the rubbing member 11 should be used. Inkjet recording apparatus and recording head capable of extending the life of the recording head 5 while maintaining the ink ejection performance of the recording head 5 at low cost and without increasing ink consumption and lowering throughput. A discharge recovery method is provided.

In each of the above-described embodiments, as a method of removing ink from the ejection port 52, a method of using short pulse driving of the recording heater 55 and wiping together (first and third embodiments), Although the method of pressing the cap 17 (second embodiment) has been described, the invention is not limited to this.
Other methods such as a method of discharging while stopping the ink supply or a method of driving the discharging heater at a high frequency with a discharging pulse width may be used. Further, in each of the above-described embodiments, the sub-heater 56 is used in consideration of the life of the heater surface as a means for heating the vicinity of the discharge port 52 to a temperature at which the adhered matter can be removed. When it is not necessary to consider the surface life of the recording heater 55, such as when it is disposable, the recording (discharging) heater may be used for heating. In that case, the cost can be further reduced by omitting the sub-heater.

Further, the heating means does not necessarily have to be built in the recording head 5, and a heating means such as a heating plate arranged outside may be used. In that case, the cost of the recording head itself can be reduced. Further, in each of the above-described embodiments, the natural cooling by the standby operation is used as the cooling means of the recording head 5. However, the preliminary discharge with a low duty during the standby operation or the carriage 4 without recording is performed.
The cooling effect may be enhanced by a method such as a blank scan, or a forced cooling means such as a fan may be provided. By doing so, it is possible to shorten the standby operation time and further improve the throughput. Further, when the ejection recovery method of the present invention is applied to a color recording apparatus, if an independent recovery time is set for each recording head and an independent recovery operation can be performed,
Unnecessary ink consumption can be eliminated.

In each of the above-described embodiments, the serial recording method in which the recording means (recording head) is moved in the main scanning direction has been described as an example. However, the present invention is not limited to the full width or one width of the recording material. Even in the case of a line recording method for recording only by sub-scanning using a line recording means having a length that covers a portion,
The same can be applied and the same effect can be achieved. Further, the present invention provides a single-color recording device for recording with one recording device, a color recording device using a plurality of recording devices for recording with different colors, or a plurality of recording devices for recording with the same color but different densities. Gradation recording device used,
Furthermore, in the case of a recording device that combines these,
The same can be applied and the same effect can be achieved.

Further, according to the present invention, when a replaceable head cartridge in which a recording head and an ink tank are integrated is used, or when the recording head and the ink tank are provided separately and the space between them is connected by a tube for ink supply or the like. The same can be applied to any arrangement of the recording head and the ink tank, and similar effects can be obtained.

The present invention can be applied to an ink jet recording apparatus that uses a recording means (recording head) using an electromechanical transducer such as a piezo element, but among them, thermal energy is used. Then, an excellent effect is brought about in an ink jet recording apparatus which uses a recording means of a method of ejecting ink. This is because such a system can achieve high density recording and high definition recording.

Regarding the typical structure and principle thereof, see, for example, US Pat. Nos. 4,723,129 and 4740.
This is preferably done using the basic principles disclosed in 796. This method can be applied to both the so-called on-demand type and the continuous type, but particularly in the case of the on-demand type, a liquid (ink) is used.
By applying at least one drive signal to the electrothermal converter arranged corresponding to the sheet or liquid path in which is stored, which corresponds to the recorded information and causes a rapid temperature rise exceeding nucleate boiling. , Generates heat energy in the electrothermal converter to cause film boiling on the heat acting surface of the recording means (recording head), and as a result, bubbles can be formed in the liquid (ink) in a one-to-one correspondence with this drive signal. So effective.

Due to the growth and contraction of the bubbles, the liquid (ink) is ejected through the ejection opening to form at least one droplet. It is more preferable to make the driving signal into a pulse shape because bubbles can be grown and contracted immediately and appropriately, and thus a liquid (ink) with excellent responsiveness can be ejected. As this pulse-shaped drive signal, US Pat.
Those described in US Pat. Nos. 4,633,359 and 4,345,262 are suitable. Incidentally, US Pat. No. 43131 of the invention relating to the rate of temperature rise of the heat acting surface.
If the conditions described in the specification of No. 24 are adopted, more excellent recording can be performed.

As the constitution of the recording head, in addition to the combination constitution of the ejection port, the liquid passage, and the electrothermal converter (the linear liquid passage or the right-angled liquid passage) as disclosed in the above-mentioned specifications, US Pat. No. 4,558,333, US Pat. No. 4,558,333, which discloses a configuration in which a heat acting portion is arranged in a bending region.
A configuration using the specification of No. 459600 is also included in the present invention. In addition, Japanese Laid-Open Patent Publication No. 123670/1984 discloses a configuration in which a common slit is used as a discharge portion of the electrothermal converter for a plurality of electrothermal converters, and an opening for absorbing a pressure wave of thermal energy. The present invention is also effective as a structure based on Japanese Patent Laid-Open No. 138461/1984, which discloses a structure in which the discharge section is associated with the discharge section. That is, according to the present invention, recording can be reliably and efficiently performed regardless of the form of the recording head.

Further, as described above, the present invention can be effectively applied to a full line type recording head having a length corresponding to the maximum width of a recording material (recording medium) which can be recorded by the recording apparatus. . As such a recording head,
Either a structure that satisfies the length by combining a plurality of recording heads or a structure as one recording head integrally formed may be used. In addition, even with the serial type as in the above example, the recording head fixed to the device main body,
Alternatively, a replaceable chip-type recording head that can be electrically connected to the device body and supply ink from the device body when mounted on the device body, or an ink tank is integrally provided on the recording head itself. The present invention is also effective when the cartridge type recording head described above is used.

Further, it is preferable to add recovery means or preliminary auxiliary means to the recording head provided as a constitution of the recording apparatus in the present invention because the effect of the present invention can be further stabilized. Specifically, in addition to the above-mentioned capping means, cleaning means, and suction recovery means for the recording head, a pressure-type recovery means, an electrothermal converter, or a heating other than this. It is also effective to perform stable recording by performing a preliminary heating means using an element or a combination thereof and a preliminary ejection mode for performing ejection different from recording.

As described above, regarding the type and number of recording heads to be mounted, for example, only one is provided corresponding to a single color ink, or a plurality of recording heads having different recording colors and densities are provided. A plurality of inks may be provided corresponding to the ink. That is, for example, the recording mode of the recording apparatus is not limited to the recording mode of only the mainstream color such as black, but may be either the recording head is integrally configured or a combination of a plurality of recording heads may be used. The present invention is extremely effective for an apparatus provided with at least one of color colors or full colors by color mixing.

In addition, in the above-described embodiments of the present invention, the ink is described as a liquid, but it is an ink that solidifies at room temperature or lower and that softens or liquefies at room temperature, or an ink jet. In the method, the temperature of the ink itself is generally adjusted within a range of 30 ° C. or higher and 70 ° C. or lower to control the temperature of the ink so that the viscosity of the ink is within a stable ejection range. It may be in a liquid form. in addition,
Whether the temperature rise due to thermal energy is positively used as the energy for changing the state of the ink from the solid state to the liquid state, or the ink that solidifies when left standing for the purpose of preventing evaporation of the ink is used. In any case, the ink is liquefied by applying the thermal energy according to the recording signal and the liquid ink is ejected,
The present invention is also applicable to the case of using an ink that has a property of being liquefied only by thermal energy, such as one that has already started to solidify when it reaches the recording medium.

The ink in such a case is disclosed in JP-A-54-54.
As described in JP-A-56847 or JP-A-60-71260, a form in which the electrothermal converter is opposed to a liquid sheet or a solid material held in the recesses or through holes of the porous sheet. May be In the present invention, the most effective one for each of the above-mentioned inks is to execute the above-mentioned film boiling method.

In addition, as the form of the ink jet recording apparatus according to the present invention, besides the one used as an image output terminal of an information processing apparatus such as a computer, a copying apparatus combined with a reader or the like, and a facsimile apparatus having a transmitting / receiving function. And the like may be used.

[0058]

As is clear from the above description, according to the first aspect of the invention, in the ink jet recording apparatus for recording by ejecting ink from the recording means to the recording material, the ink in the ejection port of the recording means is An ink removing step of removing ink, a heating means for heating the vicinity of the ejection port, and a cooling means for cooling the vicinity of the ejection port; A heating step of heating the ink to the preset temperature, an ink filling step of refilling the ink into the discharge orifice under the first preset temperature, and a cooling step of cooling the vicinity of the discharge orifice to the second preset temperature. Since it is configured to perform the ejection recovery operation including, it is possible to maintain the ink ejection performance of the recording unit without using a rubbing member, at low cost, and without causing an increase in ink consumption and a decrease in throughput. The ink jet recording apparatus is provided which can be highly life of the recording means.

According to the invention of claim 2, in addition to the structure of claim 1, there is provided a wiping member for wiping and cleaning the discharge port surface, and the discharge recovery operation is performed under the first set temperature. Since the configuration includes a wiping step of wiping the discharge port surface once or more with the wiping member, an inkjet recording apparatus capable of achieving the above effect more efficiently is provided.

According to the fifth aspect of the invention, in the ejection recovery method for maintaining the ink ejection performance of the recording means, the ink removing step of removing the ink in the ejection openings of the recording means and the first set temperature near the ejection openings. Heating step of heating to the first, and the first
Since the configuration includes an ink filling step of refilling the ink in the ejection port under the set temperature and a cooling step of cooling the vicinity of the ejection port to the second set temperature, the rubbing member should be used. There is provided a discharge recovery method that can achieve long life of the recording unit while maintaining the ink discharge performance of the recording unit at low cost and without increasing the ink consumption amount and decreasing the throughput.

According to a sixth aspect of the invention, in addition to the configuration of the fifth aspect, a configuration including a wiping step of wiping the ejection opening surface of the recording means with the wiping member at least once under the first set temperature. Therefore, the ejection recovery method capable of achieving the above effect more efficiently is provided.

[Brief description of drawings]

FIG. 1 is a schematic partial plan view illustrating the configuration of a main part of an inkjet recording apparatus suitable for applying the present invention.

FIG. 2 is a partial perspective view schematically showing the structure of an ink ejection portion of the recording means in FIG.

FIG. 3 is an enlarged perspective view of the discharge recovery device in FIG.

FIG. 4 is a schematic partial perspective view showing a wiping operation of the elastic blade and a rubbing operation of a rubbing member in FIGS. 1 and 3.

FIG. 5 is a flowchart showing a sequence of a first embodiment of a discharge recovery operation according to the present invention.

FIG. 6 is a flowchart showing a sequence of a second embodiment of the discharge recovery operation according to the present invention.

FIG. 7 is a flowchart showing a sequence of a third embodiment of the discharge recovery operation according to the present invention.

8A and 8B are diagrams showing a film having low ink repellency formed in the vicinity of an ejection port of a recording unit, in which FIG. 8A is a side view and FIG. 8B is a front view.

9A and 9B are diagrams showing an ink thickened substance attached to a downstream end of a discharge port of a recording unit in a wiping direction, wherein FIG. 9A is a vertical sectional view and FIG. 9B is a front view.

[Explanation of symbols]

 1 platen 2 recording material 3 guide shaft 4 carriage 5 recording means (recording head) 6 ejection recovery device 7 capping means 9 suction pump 10 elastic blade (wiping member) 11 rubbing member (rubbing member) 51 ejection port surface 52 ejection port 53 common liquid chamber 54 liquid path 55 electrothermal converter (for recording) 56 electrothermal converter (sub-heater)

Continuation of front page (51) Int.Cl. ⁶ Identification code Office reference number FI technical display location B41J 2/185 B41J 3/04 102 R

Claims (6)

[Claims] 1. In an inkjet recording apparatus for recording by ejecting ink from a recording means to a recording material, an ink removing means for removing ink in an ejection port of the recording means,
An ink removing step of removing ink in the ejection port of the recording unit, including a heating unit for heating the vicinity of the ejection port and a cooling unit for cooling the vicinity of the ejection port, and heating for heating the vicinity of the ejection port to a first set temperature. Performing a discharge recovery operation including a process, an ink filling process of refilling the discharge port with ink under the first set temperature, and a cooling process of cooling the vicinity of the discharge port to a second set temperature. An inkjet recording device characterized by the above. 2. A wiping member for wiping and cleaning the ejection opening surface, wherein the ejection recovery operation includes a wiping step of wiping the ejection opening surface with the wiping member at least once under the first set temperature. The ink jet recording apparatus according to claim 1, wherein 3. The inkjet recording apparatus according to claim 1, wherein the recording unit is an inkjet recording unit including an electrothermal converter that generates thermal energy used to eject ink. 4. The ink jet recording apparatus according to claim 3, wherein the recording unit ejects the ink from the ejection port by utilizing film boiling generated in the ink by the thermal energy generated by the electrothermal converter. . 5. In an ejection recovery method for maintaining the ink ejection performance of a recording means, an ink removing step of removing ink in the ejection opening of the recording means, and a heating step of heating the vicinity of the ejection opening to a first set temperature. An ejection recovery method comprising: an ink filling step of refilling the ejection port with ink under the first set temperature; and a cooling step of cooling the vicinity of the ejection port to a second set temperature. 6. The ejection recovery method according to claim 5, further comprising a wiping step of wiping the ejection opening surface of the recording unit at least once with the wiping member under the first set temperature.