JP3958893B2 - Ink jet recording apparatus and recording head cleaning control method in the same - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an ink jet recording apparatus that includes a recording head that moves in the width direction of a recording sheet and prints an image on the recording sheet by ejecting ink droplets toward the recording sheet based on print data. The present invention relates to a control technology for a recording head cleaning process for recovering the printing function of the recording head by sucking ink from the nozzle opening of the recording head.
[0002]
[Prior art]
Inkjet recording apparatuses are used for many printing including color printing in recent years because noise during printing is relatively small and small dots can be formed with high density. Such an ink jet recording apparatus includes an ink jet recording head that receives ink supplied from an ink cartridge, and a paper feeding unit that moves the recording paper relative to the recording head. The recording head is recorded on the carriage. Recording is performed by ejecting ink droplets onto the recording paper while moving in the width direction of the paper.
[0003]
For example, a black recording head that discharges black ink and a color recording head that can discharge yellow, cyan, and magenta inks are mounted on a common carriage. Full color printing is made possible by changing the ink ejection ratio.
[0004]
The recording head described above performs printing by ejecting ink pressurized in the pressure generation chamber as ink droplets from a nozzle onto a recording sheet. For example, an increase in ink viscosity caused by evaporation of a solvent from the nozzle opening, There is a problem in that printing failure occurs due to solidification of dust, adhesion of dust, and mixing of bubbles.
[0005]
For this reason, when the nozzle opening is clogged or when the ink cartridge is replaced, the nozzle forming surface of the recording head is sealed by the capping means, and the ink is discharged from the nozzle opening by the negative pressure from the suction pump. Is provided with a function of eliminating clogging due to ink solidification at the nozzle opening and the like, and a problem of ink ejection failure due to mixing of bubbles into the ink flow path, which is called a cleaning operation.
[0006]
When performing this cleaning operation, for example, it is effective to generate a flow as fast as possible in the ink in the ink flow path from the ink cartridge to the nozzle opening of the recording head. Bubbles present in the flow path can also be discharged. However, in order to increase the ink flow rate during the cleaning operation, it is necessary to increase the capacity of the suction pump in order to obtain a large negative pressure. For this purpose, along with the increase in size of the pump, it is necessary to use a large motor for driving the pump, which inevitably increases the cost and the size of the entire apparatus.
[0007]
Therefore, a valve unit that can be opened and closed is disposed in the ink flow path between the ink cartridge and the recording head, and when the ink suction is started via the capping means in the cleaning operation, the valve unit is brought into a valve closed state. A recording apparatus has been proposed in which the valve unit is opened when the negative pressure in the capping means rises to instantaneously increase the flow rate of ink in the recording head.
[0008]
According to the above-described configuration, it is possible to discharge the solidified or thickened ink in the vicinity of the nozzle of the recording head relatively easily without providing a suction pump in order to obtain a large negative pressure, and to mix in the ink flow path. It is possible to obtain an effect that the generated bubbles can be discharged by the fast flow of ink. Since the suction action from the nozzle is instantaneously performed, as a result, a cleaning effect can be obtained with a relatively small ink discharge amount.
[0009]
[Problems to be solved by the invention]
By the way, in the ink cartridge for supplying ink to the recording head described above, the outer case is generally made of a material such as polypropylene, and a porous body is loaded therein, and the ink is held by the porous body. Yes. The inside of the ink cartridge is deaerated when shipped, and the deaeration makes it possible to ensure replacement filling properties (reliability of operation of the recording apparatus when the ink cartridge is replaced and loaded). .
[0010]
After the ink cartridge thus deaerated is loaded into the recording apparatus, the air gradually flows in through the opening provided on the upper surface of the cartridge as the ink is consumed. The degree decreases.
[0011]
Here, while the degree of deaeration in the ink cartridge is ensured, when the ink is sucked by the capping means, bubbles smaller than the nozzle diameter generated in the cap cause the head flow due to the negative pressure of the ink cartridge. Although flowing back into the channel, this type of bubble disappears because it is smaller than the critical radius.
[0012]
While the degree of deaeration is ensured, the fine bubbles in the ink flow path are also dissolved in the ink, and as a result, there is a low probability of printing failure due to missing dots due to the bubbles. However, when the degree of deaeration of the ink in the cartridge is reduced, the ability to dissolve microbubbles is also reduced, so that problems such as defective printing occur due to the influence of the bubbles.
[0013]
Therefore, by applying a negative pressure over a predetermined time during the cleaning operation of the recording head, the degree of deaeration of the ink in the recording head can be improved. It grows as a unit and is pushed out by the flow of ink.
[0014]
The present invention pays attention to the above-mentioned actual situation, and during the cleaning operation, the valve unit disposed in the ink flow path between the ink cartridge and the nozzle opening of the recording head is opened to instantaneously increase the ink flow velocity. And an ink jet recording apparatus in which bubbles in the ink flow path can be easily discharged by setting a waiting time for promoting the deaeration action in advance, and a recording head cleaning control method in the apparatus Is intended to provide.
[0015]
[Means for Solving the Problems]
A preferred embodiment of an ink jet recording apparatus according to the present invention to achieve the above object includes an ink jet recording head that receives ink supplied from an ink cartridge and ejects ink droplets from nozzle openings. A capping unit that seals the nozzle opening of the recording head and sucks and discharges ink droplets from the nozzle opening by negative pressure; and an ink disposed between the ink cartridge and the nozzle opening of the recording head. An ink jet recording apparatus comprising: a valve unit that opens and closes a flow path; and an ink flow path between the valve unit and a nozzle opening of the recording head, the filter member disposed on the recording head. When the valve unit is closed, the capping means The nozzle opening of the recording head is sealed and negative pressure is applied, and the state in which the negative pressure in the internal space of the capping unit is maximized is maintained for a predetermined time, and the valve unit is controlled to open after the predetermined time has elapsed. The predetermined time is a time required for improving the degree of deaeration of the ink between the valve unit and the nozzle opening of the recording head and collecting bubbles on the upstream side of the filter member. It is characterized by being.
[0016]
In this case, preferably, the valve unit driving means is configured to control the valve unit to open after a predetermined time has elapsed after stopping the driving of the suction pump that sucks the internal space of the capping means to a negative pressure.
[0017]
The recording head cleaning control method according to the present invention includes: an ink jet recording head that receives ink supplied from an ink cartridge and ejects ink droplets from a nozzle opening; and the nozzle opening of the recording head is sealed. A capping unit that sucks and discharges ink droplets from the nozzle opening by negative pressure; a valve unit that is disposed in the recording head and opens and closes an ink flow path between the ink cartridge and the nozzle opening of the recording head; and the valve unit And a recording head cleaning control method in an ink jet recording apparatus having an ink flow path between the nozzle opening of the recording head and a filter member disposed on the recording head, the capping means A key for sealing the nozzle opening of the recording head. A capping step, a valve unit closing step for closing the valve unit, a pump drive start step for driving the suction pump to apply a negative pressure to the internal space of the capping means, and a negative for the internal space of the capping means A negative pressure holding step for holding the time when the pressure is maximized for a time required for the air between the valve unit and the nozzle opening of the recording head to be degassed and the bubbles on the upstream side of the filter member to be accumulated; A valve unit opening step for performing valve opening control of the valve unit after the elapse of time is executed.
[0018]
In this case, the capping step and the valve unit closing step are executed simultaneously in the passage of time or with the front-rear relationship being exchanged.
[0020]
According to the ink jet recording apparatus configured as described above and the recording head cleaning control method in the apparatus, a valve unit is arranged in the ink supply path between the ink cartridge and the nozzle opening, and the valve unit is a capping unit. Thus, the opening and closing thereof is controlled in conjunction with the cleaning operation for sucking ink droplets from the nozzle openings. Then, by opening the valve unit while accumulating the negative pressure, for example, bubbles that have entered the recording head when the ink cartridge is replaced can be efficiently discharged along with the rapid ink flow. It becomes possible.
[0021]
In addition, the valve unit driving means holds the state in which the maximum negative pressure is accumulated for a predetermined time and operates so as to control the valve unit to open after the predetermined time has elapsed. The bubbles generated by the deaeration action grow together with other bubbles existing on the upstream side of the filter member, and can be pushed out at once by the flow of ink. In this case, by applying a sufficient negative pressure in the capping means in advance, it is possible to quickly move the bubbles and discharge them from the nozzle openings, resulting in a rather reduced ink discharge amount. Can do.
[0022]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an ink jet recording apparatus employing a recording head cleaning control method according to the present invention will be described based on an embodiment shown in the drawings. FIG. 1 is a perspective view showing the basic configuration of an ink jet recording apparatus to which the present invention can be applied. In the drawing, reference numeral 1 denotes a carriage. The carriage 1 is guided by a guide member 4 and reciprocated in the axial direction of the platen 5 via a timing belt 3 that reciprocates by driving of a carriage motor 2. Yes.
[0023]
A recording head 7 is mounted on the side of the carriage 1 facing the recording paper 6, and a black ink cartridge 8 and a color ink cartridge 9 for supplying ink to the recording head 7 are detachably loaded on the recording head 7. ing.
[0024]
In the figure, reference numeral 10 denotes a capping unit disposed at a home position outside the non-printing area, and the capping unit 10 has a size capable of sealing each nozzle opening formed on the nozzle formation surface of the recording head 7. Is formed. A suction pump 11 for applying a negative pressure to the internal space of the capping unit 10 is disposed below the capping unit 10.
[0025]
The capping means 10 is configured to be able to move up and down as the carriage 1 moves to the home position, and functions as a lid for preventing the nozzle opening from being dried during the rest period of the recording apparatus. Functions as an ink receiver during a flushing operation in which an ink droplet is ejected by applying a drive signal unrelated to printing, and a negative pressure from the suction pump 11 is applied to the recording head 7 so that the recording head 7 It also has a function as a cleaning means for sucking and discharging ink from each nozzle opening.
[0026]
Further, a wiping member 12 made of an elastic plate such as rubber is disposed adjacent to the capping means 10, and protrudes to the moving path of the recording head 7 as necessary, for example, to suck ink by the capping means 10. It acts to wipe the nozzle forming surface of the subsequent recording head 7.
[0027]
Next, FIGS. 2 and 3 schematically show the capping means 10. FIG. 2 shows the capping means 10 as viewed from above, and FIG. 3 shows the AA line in FIG. 2 as viewed in the direction of the arrow. A state in which the recording head 7 is sealed is shown.
[0028]
2 and 3, the capping means 10 has a rectangular cap case 21 with an open upper surface, and a cap member 22 disposed in the cap case 21 and formed into a cup shape by an elastic member having ink resistance. It is comprised by. The cap member 22 is formed such that the upper edge protrudes slightly from the cap case 21.
[0029]
In addition, an ink absorbing material 23 made of a porous material excellent in ink resistance and ink absorbability is accommodated in the inner bottom portion of the cap member 22. The ink absorbing material 23 is held in the cap member 22 by a plurality of holding bodies 22a that are integrally formed with the cap member 22 so as to protrude in the horizontal direction.
[0030]
Further, an ink suction port 24 and an air release port 25 are disposed so as to penetrate the lower bottom portions of the cap case 21 and the cap member 22. The ink suction port 24 and the air release port 25 are arranged so as to be located at a predetermined interval along the substantially center in the longitudinal direction of the capping unit when the capping unit 10 is viewed from above. The ink suction port 24 is connected to the suction pump 11 via a tube (not shown), and the atmosphere release port 25 is connected to an atmosphere release valve 26 (to be described later) via a tube (not shown).
[0031]
On the other hand, the capping means 10 is constructed so as to be lifted in conjunction with the movement of the carriage toward the home position, thereby sealing the nozzle forming surface 7a of the recording head 7 as shown in FIG. Capped state. The air release valve 26 is also configured to receive a valve closing action in conjunction with the movement of the carriage toward the home position.
[0032]
The recording head 7 is provided with nozzle openings 7b through which black, cyan, magenta, and yellow inks are individually ejected, and the piezoelectric vibrators 7c arranged corresponding to the nozzle openings 7b. Each ink is ejected by the above action.
[0033]
Therefore, by closing the atmosphere release valve 26 connected to the atmosphere release port 25 in the capping means 10 and operating the suction pump 11 connected to the ink suction port 24, negative pressure is applied to the internal space of the cap member 22. Can be applied. As a result, a cleaning operation for sucking and discharging ink from each nozzle opening 7 b in the recording head 7 is executed.
[0034]
Further, by opening the air release valve 26 connected to the air release port 25 and operating the suction pump 11, the ink discharged into the cap member 22 is sucked to the suction pump 11 side, and the sucked ink is sucked. Can be discharged to a waste ink tank 27 to be described later.
[0035]
Next, FIG. 4 shows a configuration of a valve unit arranged between the recording head 7 and the ink cartridge (the black ink cartridge 8 is shown in the figure). FIG. 4A and FIG. 4B are cross-sectional views viewed from directions orthogonal to each other. FIG. 4 shows a state in which the nozzle forming surface of the recording head is sealed by the capping means 10 rising from below.
[0036]
Reference numeral 8 in FIG. 4 indicates an ink cartridge. The ink cartridge 8 is generally provided with a film member (not shown) attached to the ink supply port 8a to prevent volatilization of the ink solvent during storage. Yes.
[0037]
When a new cartridge is to be mounted, the ink supply port 8a of the cartridge 8 faces the hollow ink supply needle 31 established upward from the back surface of the recording head 7 and is pushed in as it is. Thus, the cartridge 8 can be mounted. By this operation, the ink supply needle 31 passes through the film adhered to the ink supply port 8a, and is in close contact with the rubber seal member 8b disposed therein, whereby recording is performed from the cartridge 8. Ink is supplied to the head 7.
[0038]
As shown in FIG. 4, a valve unit 36 that opens and closes an ink supply path 35 between the ink cartridge 8 and the nozzle opening of the recording head 7 is disposed above the recording head 7. The valve unit 36 is configured such that a shaft 37 inserted and arranged so as to cross the ink supply path 35 is rotatable, and is kept secret by a pair of O-rings 36a. Yes. An ink conduction hole 36b is formed in a portion of the shaft 37 crossing the ink supply path 35 in a direction orthogonal to the axial direction of the shaft.
[0039]
Therefore, the gear 38 disposed on the shaft 37 is rotated by an actuator (not shown) so that the conduction hole 36b and the ink supply path 35 are aligned on a straight line, so that the valve unit 36 is opened, and the conduction hole. The valve unit 36 is controlled to be in a closed state by causing the ink supply path 35 and the ink supply path 35 to be in a mismatched state on a straight line.
[0040]
Further, a filter member 7d is disposed in the ink supply path 35 between the valve unit 36 and the nozzle opening in the recording head 7. The filter member 7d is disposed immediately below the valve unit 36 as shown in the figure, and removes foreign matter present in the ink supplied from the ink cartridge 8 and generates foreign matter due to the rotation of the valve unit 36 and the like. In this case, it is possible to prevent these from entering the recording head 7 and to prevent the printing head 7 from causing a printing failure.
[0041]
4 is configured to open and close an ink supply path 35 between, for example, the black ink cartridge 8 and the black ink nozzle opening in the recording head 7. The cyan, magenta, and yellow ink supply paths supplied from the color ink cartridge 9 are similarly arranged. Of course, the valve unit 36 is not limited to a specific one as shown in FIG. 4, and a valve unit having another configuration can be used.
[0042]
Next, FIG. 5 shows a configuration of a control circuit mounted on the recording apparatus having the above-described configuration. Note that the carriage 1, the recording head 7, the ink cartridges 8 and 9, the capping means 10, the suction pump 11, the air release valve 26, and the waste ink tank 27 that have already been described with reference to FIG. Detailed explanation is omitted.
[0043]
In FIG. 5, reference numeral 40 denotes print control means, which generates bitmap data based on print data supplied from the host computer, and generates a drive signal by the head drive means 41 based on this data, so that the recording head 7 from which ink is ejected. The head drive unit 41 is configured to receive a flushing command signal from the flushing control unit 42 in addition to a drive signal based on the print data and output a drive signal for the flushing operation to the recording head 7.
[0044]
Reference numeral 43 denotes a cleaning control means. The pump driving means 44 is operated by a command from the cleaning control means 43 to drive and control the suction pump 11. The cleaning control unit 43 is configured to be supplied with a cleaning command signal from the printing control unit 40, the cleaning sequence control unit 45, and the cleaning command detection unit 46.
[0045]
A command switch 47 is connected to the cleaning command detection means 46. When the user pushes the switch 47, for example, a manual cleaning operation is performed by operating the detection means 46. Has been.
[0046]
The cleaning sequence control means 45 is configured to receive a command signal from a host computer and to send control signals to the cleaning control means 43, the valve unit driving means 48 and the carriage driving means 49.
[0047]
The valve unit driving means 48 operates to send a control signal to an actuator that drives a gear 38 disposed on the shaft 37 shown in FIG. 4 to open and close the valve unit 36, and the carriage driving means 49 The carriage motor 2 shown in FIG. 1 is driven to move the carriage 1 to the home position, for example, and the capping unit 10 controls the recording head 7 to be capped.
[0048]
FIG. 6 is a flowchart showing the cleaning operation of the recording head performed by the configuration of the recording apparatus described above, and the sequence of the cleaning operation will be described below with reference to FIG. For example, when a cleaning command is received on the utility in the host computer, a control signal is sent from the host computer to the cleaning sequence control means 45 as shown in FIG. 5, and the cleaning operation starts.
[0049]
When the cleaning operation starts, the nozzle forming surface of the recording head 22 is wiped by the wiping member 12 as shown in step S11. This is because the sequence control means 45 sends a control signal to the carriage drive means 49, and the wiping member 12 protrudes into the movement path of the recording head 7 in the process of moving the carriage 1 toward the home position side. This is achieved by wiping the nozzle forming surface 7. Thereby, paper dust and the like adhering to the nozzle forming surface of the recording head 7 are removed.
[0050]
Subsequently, as shown in step S12, the carriage 1 still moves to the home position side, and accordingly, as shown in step S13, the 7 nozzle formation surfaces of the recording head are capped by the capping means 10. At the same time, the air release valve 26 communicating with the air release port 25 in the capping means 10 is also closed as shown in step S14.
[0051]
In this state, the valve unit 36 is closed as shown in step S15. This is done by sending a control signal to the valve unit driving means 48 from the sequence control means 45 shown in FIG.
[0052]
Subsequently, the driving of the suction pump 11 is started as shown in step S16. This is done by sending a control signal from the sequence control means 45 shown in FIG. 5 to the cleaning control means 43 and sending a control signal from the cleaning control means 43 to the pump drive means 44.
[0053]
The suction pump 11 is a so-called tube pump that applies a squeezing action to a tube arranged in an arc shape by a roller that moves along an arc-shaped locus. Therefore, the negative pressure in the internal space of the capping means 10 gradually increases due to the presence of the volume of the internal space of the tube and the internal space of the capping means 10.
[0054]
Then, in the state where the negative pressure in the internal space of the capping means 10 is maximized, the suction pump is stopped as shown in step S17, and in this state, the passage of a predetermined time is waited as shown in step S18. Thereby, a negative pressure is applied to the ink supply path 35 from the nozzle opening of the recording head 22 to the valve unit 36 over a predetermined time.
[0055]
After the predetermined time has elapsed, the valve unit 36 is opened as shown in step S19. The sequence control unit 45 manages the predetermined time as described above and sends a control signal to the valve unit driving unit 48 to cause the valve unit 36 to perform a valve opening operation.
[0056]
FIG. 7 shows the state of negative pressure applied to the internal space of the capping means 10 made in steps S16 to S19. That is, as shown in FIG. 7, at the same time as driving of the pump is started, the negative pressure in the internal space of the capping means 10 rises along a locus like a quadratic curve. Then, the suction pump is stopped in a state where the negative pressure is maximized, and the passage of a predetermined time is awaited in this state.
[0057]
During the elapse of the predetermined time, the inside of the ink supply path 35 from the nozzle opening of the recording head 22 to the valve unit 36 is subjected to a negative pressure, so that the ink existing in the ink flow path in the valve unit from the nozzle opening is Due to the negative pressure, the degree of deaeration increases, and the fine bubbles generated thereby are accumulated as bubbles and grow together with other bubbles.
[0058]
After the lapse of the predetermined time, the valve unit 36 is opened as described above, so that an early ink flow is generated in the ink supply path from the ink cartridges 8 and 9 to the recording head 22, and the ink with the thickened ink is used. Bubbles grown in the flow path are discharged to the capping means 10 side together with the ink. Along with this, the negative pressure in the internal space of the capping means 10 is eliminated.
[0059]
In this case, as shown in FIG. 4, in the configuration in which the filter member 7d is disposed in the ink supply path 35 between the valve unit 36 and the nozzle opening, bubbles are accumulated on the upstream side of the filter member 7d. However, as described above, the bubbles generated by the deaeration action by applying the negative pressure for a predetermined time as described above grow integrally with the bubbles existing on the upstream side of the filter member 7d. The action of being pushed out by the flow of this occurs.
[0060]
Therefore, in the recording apparatus in which the filter member 7d is arranged as described above, adopting the sequence as described above can contribute to further improving the bubble discharging effect.
[0061]
In step S20, the capping of the recording head 7 by the capping unit 10 is released. Then, as shown in step S21, the suction pump 11 is temporarily driven and stopped. As a result, the ink discharged into the capping unit 10 passes through the suction pump 11 and is discarded in the waste ink tank 27.
[0062]
In the subsequent step S22, it is determined whether or not the number of ink suctions has been performed a predetermined number of times. If the number of ink suctions has not reached the predetermined number of times, the above-described steps S13 to S21 are repeatedly performed. When it is determined in step S22 that the number of times of ink suction has been executed a predetermined number of times, a wiping operation is executed as shown in step S23, and the ink adhering to the nozzle formation surface of the recording head is wiped by the wiping member 12. The The recording head 7 is sealed by the capping means 10 and is in a state of waiting for the arrival of print data.
[0063]
In the sequence shown in FIG. 6, the valve unit closing step shown in step S15 is executed after the capping step shown in step S13. However, these steps may be performed simultaneously in the passage of time. Or, the context may be interchanged.
[0064]
In the sequence shown in FIG. 6, it is determined in step S22 whether or not the ink suction frequency has been executed a predetermined number of times. However, a sufficient cleaning result can be obtained by one ink suction operation. If so, there is no need to repeat multiple times.
[0065]
【The invention's effect】
As apparent from the above description, according to the ink jet recording apparatus and the recording head cleaning control method of the present invention, a valve unit for opening and closing the ink supply path is disposed between the ink cartridge and the recording head. Since the negative pressure is accumulated by controlling the opening and closing of the valve unit in conjunction with the cleaning operation of the recording head, bubbles that have entered the recording head when the ink cartridge is replaced, for example, It becomes possible to discharge efficiently along with the flow.
[0066]
In addition, the valve unit driving means keeps the state where the maximum negative pressure is accumulated for a predetermined time and operates to control the valve unit to open after the predetermined time has elapsed. The bubbles generated by the deaeration action grow together with other bubbles upstream of the filter member, and the bubbles are pushed out by the flow of ink. Therefore, it is possible to provide a highly reliable ink jet recording apparatus that can effectively suppress the occurrence of printing defects in the recording head.
[Brief description of the drawings]
FIG. 1 is a perspective view showing a basic configuration of an ink jet recording apparatus to which the present invention can be applied.
FIG. 2 is a schematic diagram showing a state in which capping means mounted on the recording apparatus shown in FIG. 1 is viewed from above.
FIG. 3 is a schematic diagram showing a cross-sectional state of the capping means when the line AA in FIG. 2 is viewed in the direction of the arrow.
FIG. 4 is a cross-sectional view illustrating a configuration of a valve unit disposed between a recording head and an ink cartridge.
FIG. 5 is a block diagram showing an example of a control circuit provided in the recording apparatus according to the present invention.
6 is a flowchart showing a head cleaning control sequence performed by the control circuit shown in FIG. 5;
7 is a characteristic diagram showing a negative pressure application state formed in the control sequence shown in FIG. 6; FIG.
[Explanation of symbols]
1 Carriage
2 Carriage motor
3 Timing belt
4 Guide members
5 Platen
6 Recording paper
7 Recording head
7a Nozzle forming surface
7b Nozzle opening
7c Piezoelectric vibrator
7d Filter member
8 Black ink cartridge
9 Color ink cartridge
10 Capping means
11 Suction pump
24 Ink suction port
25 Open door to the atmosphere
31 Ink supply needle
35 Ink supply path
36 Valve unit
40 Print control means
41 Head drive means
42 Flushing control means
43 Cleaning control means
44 Pump drive means
45 Cleaning sequence control means
48 Valve unit drive means
49 Carriage drive means

Claims (4)

An ink jet recording head that receives ink supplied from an ink cartridge and discharges ink droplets from nozzle openings, and a capping unit that seals the nozzle openings of the recording head and sucks and discharges ink droplets from the nozzle openings by negative pressure. A valve unit that is disposed in the recording head and opens and closes an ink channel between the ink cartridge and the nozzle opening of the recording head, and an ink channel between the valve unit and the nozzle opening of the recording head An ink jet recording apparatus equipped with a filter member disposed on the recording head,
In the closed state of the valve unit, the capping means seals the nozzle opening of the recording head and applies a negative pressure, and maintains a state where the negative pressure in the internal space of the capping means is maximized for a predetermined time. And valve unit driving means for controlling the valve unit to open after the predetermined time has elapsed,
Ink-jet recording characterized in that the predetermined time is a time required for improving the degree of deaeration of ink between the valve unit and the nozzle opening of the recording head and collecting bubbles on the upstream side of the filter member. apparatus.   The valve unit driving means is configured to control the valve unit to open after a lapse of a predetermined time after driving of a suction pump that sucks the internal space of the capping means to a negative pressure. Inkjet recording apparatus. An ink jet recording head that receives ink supplied from an ink cartridge and discharges ink droplets from nozzle openings, and a capping unit that seals the nozzle openings of the recording head and sucks and discharges ink droplets from the nozzle openings by negative pressure. A valve unit that is disposed in the recording head and opens and closes an ink channel between the ink cartridge and the nozzle opening of the recording head, and an ink channel between the valve unit and the nozzle opening of the recording head A cleaning control method for a recording head in an ink jet recording apparatus equipped with a filter member disposed on the recording head,
A capping step for sealing the nozzle opening of the recording head by the capping means; a valve unit closing step for closing the valve unit; and a pump for driving the suction pump to apply a negative pressure to the internal space of the capping means. In the driving start step and the state in which the negative pressure in the internal space of the capping unit is maximized, the ink between the valve unit and the nozzle opening of the recording head is degassed, and bubbles on the upstream side of the filter member are collected. A recording head cleaning control method in an ink jet recording apparatus, comprising: a negative pressure holding step for holding a time required to perform the operation; and a valve unit valve opening step for opening the valve unit after the elapse of time. .   4. The method for controlling the cleaning of a recording head in an ink jet recording apparatus according to claim 3, wherein the capping step and the valve unit closing step are executed simultaneously with the passage of time or with the front-rear relationship reversed.

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