JP2008087217A - Inkjet recorder - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain an inkjet recorder which can reduce an ink quantity ejected together with bubbles. <P>SOLUTION: The inkjet recorder includes a recording head which ejects the ink from a manifold out of nozzle holes, and a feeding passage which supplies the ink from an ink tank to the manifold. A bubble detecting sensor is arranged upstream from an inlet of the manifold, which detects the bubbles that invade into the manifold. An ink consumption quantity C by a recording head after the bubble detecting sensor detects the bubbles is detected. When the ink consumption quantity C exceeds a volume m from a detection position by the bubble detecting sensor to the inlet of the manifold (S200: YES), small purging of ejecting out of the nozzle hole the ink according to an ink volume from the manifold to the nozzle hole is executed (S215). <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an ink jet recording apparatus that performs recording by discharging ink droplets.

  2. Description of the Related Art Conventionally, an ink jet recording apparatus has been known as a recording apparatus having a relatively simple configuration and easy high speed recording and high quality recording. In an ink jet recording apparatus, ink is supplied from an ink cartridge to a recording head via a supply channel such as a tube, and a piezoelectric element or the like is driven based on image data. The ink dot pattern is recorded on the recording medium.

Further, there may be a case where ejection failure occurs due to bubbles in the supply flow path. As disclosed in Patent Document 1 and Patent Document 2, bubble detection means for detecting bubbles in the supply flow path is provided, and the bubble detection means is a bubble. When this is detected, a purge operation or a flushing operation is performed to discharge bubbles together with the ink.
Japanese Patent Laid-Open No. 3-183562 Japanese Patent Laid-Open No. 9-240019

  However, in such a conventional apparatus, the ink is discharged until the bubbles are not detected by the bubble detection means, so that there is a problem that the amount of ink to be discharged is increased.

  The subject of this invention is providing the inkjet recording device which can reduce the amount of ink discharged | emitted with a bubble.

  In order to achieve this problem, the present invention has taken the following measures in order to solve the problem. That is, a manifold that supplies ink to at least one nozzle is provided, a recording head that discharges ink from the manifold from the nozzle hole of the nozzle, and a supply channel that supplies ink from an ink tank to the manifold. In the ink jet recording apparatus that performs recording by attaching ink ejected by the recording head to a recording medium, the bubble detection is provided upstream of the inlet of the manifold and detects bubbles entering the manifold Means, ink consumption detecting means for detecting ink consumption by the recording head after the bubble detecting means detects the bubbles, and the ink consumption detected by the ink consumption detecting means is the bubble. The volume from the detection position by the detection means to the inlet of the manifold was exceeded. To come, the inkjet recording apparatus is that which is characterized in that and a recovery means for discharging ink in accordance with the ink capacity from the manifold to the nozzle hole from the nozzle hole.

  Further, the ink consumption amount detecting means may calculate and detect the ink amount ejected from the nozzle hole by driving the recording head. Further, the supply flow path is formed by a tube, and the tube is connected to a joint on the recording head side, and the bubble detecting means is provided on the recording head between the inlet of the manifold and the joint. It is also possible to have a configuration. The recording head may include the manifold for each ink color and the nozzle hole, and the bubble detecting means may be provided for each ink color.

  Further, when the bubble detecting means continuously detects the bubbles, the ink corresponding to the ink volume in the supply channel is discharged from the nozzle hole regardless of the discharge of the ink by the recovery means. It may be provided with a large discharge recovery means.

  The ink jet recording apparatus of the present invention detects bubbles entering the manifold, detects the ink consumption of the recording head after detecting the bubbles, and the ink consumption is from the detection position of the bubble detection means to the inlet of the manifold. Since the ink corresponding to the ink capacity from the manifold to the nozzle holes is discharged when the volume of the ink is exceeded, the amount of ink discharged together with the bubbles can be reduced. Further, it is possible to effectively discharge the bubbles without providing a sub tank for storing bubbles between the manifold and the ink tank.

  When the ink consumption amount detecting means calculates the ink amount according to the drive of the recording head and detects the ink consumption amount, the ink consumption amount can be easily detected without adding hardware components. If the bubble detecting means is provided between the inlet of the manifold and the joint of the tube, it can be provided on the recording head not far from the inlet of the manifold. Further, when the recording head includes a manifold and nozzle holes for each ink color, the amount of ink discharged together with the bubbles can be reduced even by the color recording head by providing the bubble detection means for each ink color.

  When the bubble detecting means detects the bubbles continuously, it is possible to prevent the ink from being frequently discharged together with the bubbles by discharging the ink corresponding to the ink volume in the supply channel.

The best mode for carrying out the present invention will be described below in detail with reference to the drawings.
FIG. 1 is a schematic configuration diagram of an ink jet recording apparatus as an embodiment of the present invention, and FIG.

  As shown in FIGS. 1 and 2, the recording head 1 includes a nozzle plate 2 disposed in parallel with a recording medium such as recording paper (not shown). A nozzle hole 4 is formed in the nozzle plate 2 so as to open downward toward the recording medium, and a descender 6 is provided in communication with the nozzle hole 4. An ink chamber 8 is provided in communication with the descender 6, and the volume of the ink chamber 8 is changed in accordance with the driving of the piezoelectric element 10.

  By applying a voltage to the piezoelectric element 10, the piezoelectric element 10 is driven to increase the volume of the ink chamber 8, and the ink is sucked into the ink chamber 8 through the throttle channel 14. When application of voltage to the piezoelectric element 10 is stopped at a predetermined timing, the ink chamber 8 returns to its original volume and is ejected as an ink droplet from the nozzle hole 4.

  This is repeated, and the piezoelectric element 10 is driven based on the image data. The ink in the ink chamber 8 is ejected as ink droplets from the nozzle holes 4 to the recording medium, thereby recording the ink dot pattern. The recording head 1 is not limited to the one using the piezoelectric element 10 but may be configured to eject ink droplets using a heating element.

  The ink chamber 8 communicates with the manifold 16 via the throttle channel 14, and the manifold 16 is connected to the ink tank 20 via the tube 18. The throttle channel 14 is connected to the bottom surface of the ink chamber 8 so as to open in the vertical direction, and the manifold 16 is disposed below the throttle channel 14. The nozzle hole 4, descender 6, ink chamber 8, piezoelectric element 10, and throttle channel 14 constitute one nozzle.

  The recording head 1 is mounted on a carriage (not shown), and the carriage is reciprocated to perform recording including an ink dot pattern on a recording medium. The ink tank 20 is disposed, for example, on the fixed side outside the carriage, and ink is supplied to the recording head 1 via a flexible tube 18.

  As shown in FIG. 2, the manifold 16 and the supply flow path 28 are connected via a joint 22, and a tube 18 is inserted into the joint 22 provided in the recording head 1. A supply hole 24 that communicates with the tube 18 is formed in the joint 22, and a supply hole 26 that communicates with the supply hole 24 and is connected to the inlet 16 a of the manifold 16 is formed in the recording head 1. The tube 18 and the manifold 16 are communicated with each other through both supply holes 24 and 26. A supply flow path 28 is formed by the tube 18 and the supply holes 24 and 26.

  A bubble detection sensor 30 is disposed in the joint 22, and the bubble detection sensor 30 detects the bubble a passing through the supply hole 24. For example, the bubble a is detected by measuring a change in electrical resistance between a pair of electrodes provided across the supply hole 24 or by detecting a change in capacitance between the pair of electrodes. What is necessary is just to perform by what detects light emission from a light emitting element with a light receiving element, and detects the bubble a from the difference of light transmission or light reflection.

  The bubble detection sensor 30 is preferably provided at the inlet 16a of the manifold 16, but the recording head 1 is small and there is no space for providing the bubble detection sensor 30 at the inlet 16a. Therefore, the supply channel 28 is provided upstream of the inlet 16 a of the manifold 16. At this time, if the bubble detection sensor 30 is provided so as to detect the bubble a passing through the tube 18, the amount of ink between the detection position of the bubble detection sensor 30 and the inlet 16a of the manifold 16 increases, which is not preferable. Moreover, the bubble a may enter from the connection portion between the tube 18 and the joint 22, and if the bubble detection sensor 30 is provided in the tube 18, the bubble a cannot be detected.

  The position where the bubble detection sensor 30 is provided may be provided on the joint 22 where the bubble detection sensor 30 is easily provided on the upstream side of the inlet 16a of the manifold 16. Even in this case, the position where the bubble detection sensor 30 is provided is preferably as close to the inlet 16a of the manifold 16 as possible.

  On the other hand, a purge mechanism 32 is provided opposite to the nozzle hole 4 at the purge position of the carriage outside the recording position for recording on the recording medium. The purge mechanism 32 is configured to raise and lower the cap 34, cover the nozzle hole 4 with the cap 34, drive the pump 36, and suck ink from the nozzle hole 4. The purge mechanism 32 is not limited to the one that is sucked by the pump 36, and may be configured to push out ink by supplying pressurized air to the ink tank 20.

  The piezoelectric element 10, the bubble detection sensor 30, and the purge mechanism 32 are connected to a control circuit 38. The control circuit 38 controls the ink jet recording apparatus in accordance with a control program related to the operation content of the ink jet recording apparatus. Etc.

  Next, the discharge control process performed by the control circuit 38 described above will be described with reference to the flowchart shown in FIG. FIG. 3 is a flowchart showing an example of the discharge control process performed in the control circuit of this embodiment.

This discharge control process is repeatedly executed at regular intervals during printing or standby in which the carriage is reciprocated and recording is performed on the recording medium. As shown in FIG. (Step 100. Hereinafter referred to as S100. The same shall apply hereinafter). Whether or not a bubble is detected is determined by whether or not a bubble is detected by the bubble detection sensor 30. If no bubble is detected (S100: NO), this control process is terminated once and executed at regular intervals. repeat.

  While the recording head 1 is reciprocated, ink is supplied from the ink tank 20 to the ink chamber 8 via the supply flow path 28, the manifold 16, and the throttle flow path 14, and the piezoelectric element 10 is driven according to the image data. Thus, ink droplets are ejected from the nozzle holes 4, and the ink droplets are attached to the recording medium, thereby recording on the recording medium.

  As the ink is consumed, air enters from the tube 18, the connection portion between the tube 18 and the joint 22, or the air dissolved in the ink grows to generate bubbles a in the tube 18. When the bubble a moves to the recording head 1 side in the tube 18 as the ink is consumed, and the bubble detection sensor 30 detects the bubble a (s100: YES), 1 is added to the bubble counter n (S105). Since the bubble counter n is reset to 0 in an initialization process (not shown) when the power is turned on, the bubble counter n becomes 1 when the first bubble a is detected.

  Then, it is determined whether or not the bubble counter n is 1 (S110). When the first bubble a is detected, the bubble counter n is determined to be 1 (S110: YES), and the first ink consumption C1 after the first bubble a is detected is determined. Calculation is started (S115).

  The calculation of the first ink consumption amount C1 is executed by interruption at regular intervals in a different routine from this control processing by the ink consumption amount calculation processing. FIG. 4 is a flowchart showing an example of ink consumption calculation processing performed in the control circuit of the present embodiment.

  As shown in FIG. 4, the ink consumption calculation process is started after the bubble a is detected. In the ink consumption calculation process, the recording head 1 discharges from the nozzle hole 4 when recording on the recording medium. The number of ink droplets is counted from the number of times the piezoelectric element 10 is driven after the bubble a is detected (S300).

  The recording head 1 can change the size of ink droplets that can be ejected by one driving by switching the driving force of the piezoelectric element 10 to two or three stages. For example, in the case of switching to two stages, there are a large discharge amount and a small discharge amount in one ink discharge amount, and the difference in driving force of the piezoelectric element 10 is also distinguished to count the number of times the piezoelectric element 10 is driven.

  Ink consumption is calculated by multiplying the large discharge amount per time by the large discharge amount count and multiplying the small discharge amount count by the small discharge amount per time and adding them. C is calculated (S310). After the calculation, the process returns to the original process.

  After the calculation of the first ink consumption C1 is started, the processing from S100 onward is repeated, and when the bubble a is not detected (S100: NO), this control processing is terminated once and the execution is repeated at regular intervals.

  If the bubble detection sensor 30 detects the second bubble a while repeatedly executing this control process, 1 is added to the bubble counter n (S105). For the second bubble a, the bubble counter n is 2, and it is determined that the bubble counter n is not 1 (S110: NO), and then it is determined whether the bubble counter n is 3 (S120). . Since the bubble counter n is 2, it is determined that the bubble counter n is not 3 (S120: NO), and the calculation of the second ink consumption C2 is started (S125).

The calculation of the second ink consumption amount C2 is executed by interruption every predetermined time in a different routine different from this control processing by the ink consumption amount calculation processing shown in FIG. 4 as described above. The calculation of the second ink consumption C2 is performed by a routine different from the ink consumption calculation process for calculating the first ink consumption C1.

  Also in the second ink consumption calculation process, when recording on the recording medium by the recording head 1, the number of times the piezoelectric element 10 is driven is counted (S300), and the second ink consumption C2 is determined according to the amount of ink to be ejected. Calculate (S310).

  After the calculation of the second ink consumption amount C2 is started, the processing from S100 onward is repeated, and when the bubble a is not detected (S100: NO), this control processing is terminated once and the execution is repeated at regular intervals.

FIG. 5 is a flowchart showing an example of the recovery process performed in the control process of the present embodiment. This recovery process is repeatedly executed at regular intervals together with the above-described discharge control process.
As shown in FIG. 5, first, it is determined whether or not the first ink consumption C1 exceeds the volume m (S200). The first ink consumption amount C1 is calculated by executing the ink consumption amount calculation process started by the process of S115 described above, and is the ink consumption amount after the first bubble a is detected. Even after the bubble a is detected, ink droplets are ejected from the recording head 1, recording is performed on the recording medium, and ink is consumed. Therefore, ink is supplied from the ink tank 20 to the manifold 16 via the supply flow path 28, and the bubble a advances along the supply flow path 28 toward the inlet 16 a of the manifold 16.

  The volume m is the volume of the supply flow path 28 from the detection position by the bubble detection sensor 30 to the inlet 16a of the manifold 16, and is a value calculated and set in advance. When the volume m of ink is consumed, the bubble a at the detection position of the bubble detection sensor 30 reaches the inlet 16a of the manifold 16. If the bubbles a pass through the inlet 16a and enter the manifold 16, it causes discharge failure.

  FIG. 2 shows a state in which a certain set of nozzle holes 4, ink chambers 8, throttle channels 14, and piezoelectric elements 10 are provided in one manifold 16. A number of nozzle holes 4, ink chambers 8, throttle channels 14, and piezoelectric elements 10 are provided.

  When the position of the throttle channel 14 communicating with the manifold 16 is different, and the bubble a enters the manifold 16 through the inlet 16a, the bubble a enters one of the throttle channels 14, and either There is a high risk of causing a discharge failure in the nozzle hole 4.

  When the first ink consumption C1 does not exceed the volume m (S200: NO), the process returns to the original process, and when it is determined that the first ink consumption C1 exceeds the volume m (S200: YES), one pass It is determined whether or not the recording is finished (S205). When the recording head 1 performs recording on the recording medium by reciprocation and stops recording in the middle of one pass, it is difficult to resume recording from the middle of one pass. Therefore, the recording is continued until the one-pass recording is finished (S205: NO), and after the one-pass recording is finished (S205: YES), the recording by the recording head 1 is stopped (S210).

  Recording is stopped, the recording head 1 is moved to the purge position, and a small purge is executed (S215). In the small purge, the purge mechanism 32 is controlled so that the nozzle hole 4 is covered by the cap 34, and the ink is sucked and discharged from the recording head 1 by the pump 36 (S215).

The amount of ink discharged by the small purge depends on the total volume of the manifold 16 and the plurality of nozzle holes 4, the ink chamber 8, and the throttle channel 14 communicating with the same manifold 16. A little larger amount. When the ink corresponding to the total volume is discharged, the bubbles a reaching the inlet 16a of the manifold 16 can be discharged together with the ink. In this embodiment, the amount of ink discharged by this small purge is a small amount of about 0.03 cc.

  After the bubbles a are discharged by performing a small purge, a maintenance operation is performed by flushing or wiping (S220). Flushing is an operation of driving the piezoelectric element 10 and discharging a small amount of ink from the nozzle hole 4 into the cap 34 to recover a meniscus (not shown). Wiping is an operation of wiping the nozzle plate 2 with a wiper (not shown) to remove paper dust and the like.

  After the maintenance operation, 1 is subtracted from the bubble counter n (S225), the first ink consumption C1 is cleared to 0 (S230), a transition process described later is performed (S235), and the recording by the recording head 1 is performed. Recording on the medium is resumed (S240). Thereafter, the process returns to the original process.

  In this manner, the bubble a entering the manifold 16 is detected (S100), the first ink consumption C1 of the recording head 1 after the bubble a is detected is detected, and the first ink consumption C1 is detected as a bubble. When the volume m from the detection position of the sensor 30 to the inlet 16a of the manifold 16 is exceeded, ink corresponding to the ink capacity from the manifold 16 to the nozzle hole 4 is discharged, so the amount of ink discharged together with the bubbles a can be reduced. . Ink from the detection position of the bubble detection sensor 30 to the inlet 16a of the manifold 16 can be effectively used for recording.

In addition, the bubbles a can be effectively discharged without providing a sub-tank or the like for accumulating the bubbles a between the manifold 16 and the ink tank 20.
Ink consumption detection processing calculates the ink amount according to the driving of the recording head 1 and detects the first ink consumption C1, so that the ink consumption can be easily detected without adding hardware parts. Further, since the bubble detection sensor 30 is provided between the inlet 16a of the manifold 16 and the joint 22 of the tube 18, it can be provided on the recording head 1 not far from the inlet 16a of the manifold 16, and the ink consumption can be detected. The error can be reduced.

  Even in the case where the recording head 1 includes the manifold 16 and the nozzle hole 4 for each ink color, similarly, the bubble detection sensor 30 is provided for each ink color, and each ink consumption is detected. By performing a small purge when m is exceeded, the color recording head can also reduce the amount of ink discharged together with the bubbles a.

  In the present embodiment, the calculation process of the first ink consumption amount C1 and the calculation process of the second ink consumption amount C2 are performed separately. In the recovery process of the second bubble a according to the calculation process of the second ink consumption C2, it is determined whether or not the volume m has been exceeded (S200) as described above, and when the volume m has been exceeded (S200) (S200: YES) Waiting for the end of one-pass recording (S205), the recording is stopped (S210).

  Then, a small purge corresponding to the second bubble a is executed, and the ink corresponding to the total volume of the manifold 16 and the plurality of nozzle holes 4 communicating with the same manifold 16, the ink chamber 8, and the throttle channel 14. (S215), and the air bubbles a reaching the inlet 16a of the manifold 16 are discharged together with the ink.

Subsequently, after performing the maintenance operation (S220), 1 is subtracted from the bubble counter n (S225), the second ink consumption C2 is cleared to 0 (S230), and the transition process is executed (S235). . Then, recording on the recording medium by the recording head 1 is resumed (S240).
) And return to the original process.

  As described above, when the first bubble a is detected, the first ink consumption C1 after the detection is calculated, and when the first ink consumption C1 exceeds the volume m, a small purge is executed, and the manifold The bubbles a in 16 are discharged together with the ink.

  In addition, if the second bubble a is detected after the first bubble a is detected and before the small purge corresponding to the first bubble a is executed, the second ink consumption after the detection is detected. C2 is calculated. As the recording proceeds, ink is consumed, and during this time, the first ink consumption C1 and the second ink consumption C2 are calculated. Since the first ink consumption C1 exceeds the volume m first, a small purge corresponding to the first bubble a is executed.

  After the small purge is executed, the second bubble a is replaced with the first bubble a from that time. Accordingly, the calculation of the second ink consumption C2 is transferred as the calculation of the first ink consumption C1 by the shift process of S235, and the small purge with the first bubble a is performed on the first ink consumption C1. After adding the ink volume, the calculation is continued as the calculation of the first ink consumption C1.

  Then, it is determined whether or not the first ink consumption amount C1 obtained by adding the small purge ink volume in the first bubble a exceeds the volume m (S200). When the volume m is exceeded (S200: YES), a small purge corresponding to the second bubble a is executed (S215). When the volume m is exceeded as a result of adding the ink volume by the small purge of the first bubble a (S200: YES), a small purge corresponding to the second bubble a is immediately executed (S215).

  For example, when one recording process job is completed while the calculation process of the first ink consumption C1 is being executed, the first ink consumption C1 at that time is stored, and the next recording is started. If so, the calculation is continued again.

  On the other hand, before executing the small purge corresponding to the first bubble a, the second bubble a is detected, and further, three before the small purge corresponding to the first bubble a is performed. When the bubble a of the eye is detected, as shown in FIG. 3, it is determined that the bubble counter n is 3 through the processing of S100 to S120 (S120: YES). That is, there are three bubbles a in the supply flow path 28 between the detection position of the bubble detection sensor 30 and the inlet 16 a of the manifold 16. In the present embodiment, at this time, it is determined that many bubbles a continuously pass, and it is determined that the purge operation is frequently executed in the small purge by the recovery process described above.

  Therefore, it is determined whether or not the 1-pass recording has been completed (S130), and after waiting for the 1-pass recording to be completed (S130: YES), the recording by the recording head 1 is stopped (S135). Then, the purge mechanism 32 is controlled to execute a large purge (S140).

  In the large purge, similarly to the process of S215, the nozzle hole 4 is covered by the cap 34, and the ink is sucked and discharged from the recording head 1 by the pump 36. The amount of ink discharged by the large purge is the supply flow path 28 from the detection position of the bubble detection sensor 30 to the inlet 16a of the manifold 16, the manifold 16, a plurality of nozzle holes 4 communicating with the same manifold 16, the ink chamber 8, It depends on the total volume of the throttle channel 14 and is almost the same as or slightly larger than the total volume. When the ink corresponding to the total volume is discharged, the bubbles a on the downstream side from the detection position of the bubble detection sensor 30 can be discharged together with the ink. In this embodiment, the amount of ink discharged by this large purge is about 0.9 cc.

After the bubble a is discharged by executing a large purge, a maintenance operation is performed by flushing or wiping (S145). Thereafter, since all the bubbles a downstream from the detection position of the bubble detection sensor 30 have been discharged, the bubble counter n is cleared to 0 (S150), and both the first ink consumption C1 and the second ink consumption C2 are set to 0. After clearing (S155), recording on the recording medium by the recording head 1 is resumed (S160).

  In the present embodiment, large purge is executed when three bubbles a pass continuously. However, the present invention is not limited to this, and when four or more bubbles a pass continuously. In addition, a large purge may be executed. At that time, the ink consumption for each bubble a may be calculated, such as the calculation of the third ink consumption C3.

  In this embodiment, the ink consumption is calculated by counting the number of times the piezoelectric element 10 is driven. However, the present invention is not limited to this, and the ink consumption is detected by detecting the ink flow rate using a flow rate detection sensor or the like. Alternatively, the ink level of the ink tank 20 may be detected, and the ink consumption may be detected from the decrease in the ink level.

In the present embodiment, the execution of the processes of S200 to S215 serves as a recovery unit, and the execution of the processes of S120 and S130 to S145 serves as a large discharge recovery unit.
The present invention is not limited to such embodiments as described above, and can be implemented in various modes without departing from the gist of the present invention.

1 is a schematic configuration diagram of an ink jet recording apparatus as an embodiment of the present invention. FIG. 2 is an enlarged cross-sectional view illustrating a schematic configuration of a recording head of the present embodiment. It is a flowchart which shows an example of the discharge | emission control process performed in the control circuit of this embodiment. 5 is a flowchart illustrating an example of ink consumption calculation processing performed in the control circuit of the present embodiment. It is a flowchart which shows an example of the recovery process performed in the control process of this embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Recording head 2 ... Nozzle plate 4 ... Nozzle hole 8 ... Ink chamber 10 ... Piezoelectric element 14 ... Restriction flow path 16 ... Manifold 16a ... Inlet 18 ... Tube 20 ... Ink tank 22 ... Joint 24, 26 ... Supply hole 28 ... Supply Flow path 30 ... Bubble detection sensor 32 ... Purge mechanism 34 ... Cap 36 ... Pump 38 ... Control circuit a ... Bubble

Claims (5)

A recording head for supplying ink to at least one nozzle, and discharging ink from the manifold from the nozzle hole of the nozzle;
A supply flow path for supplying ink from the ink tank to the manifold,
In an inkjet recording apparatus that performs recording by attaching the ink ejected by the recording head to a recording medium,
The bubble detecting means provided on the upstream side of the inlet of the manifold and detecting bubbles entering the manifold;
Ink consumption detection means for detecting ink consumption by the recording head after the bubble detection means detects the bubbles;
When the ink consumption detected by the ink consumption detection means exceeds the volume from the detection position by the bubble detection means to the inlet of the manifold, the ink according to the ink capacity from the manifold to the nozzle hole Recovery means for discharging the nozzle hole from the nozzle hole;
An ink jet recording apparatus comprising:   The inkjet recording apparatus according to claim 1, wherein the ink consumption amount detection unit calculates and detects the amount of ink ejected from the nozzle hole by driving the recording head.   The supply flow path is formed by a tube, and the tube is connected to a joint on the recording head side, and the bubble detecting means is provided on the recording head between the inlet of the manifold and the joint. The ink jet recording apparatus according to claim 1, wherein the ink jet recording apparatus is an ink jet recording apparatus.   4. The recording head according to any one of claims 1 to 3, wherein the recording head includes the manifold and the nozzle hole for each ink color, and the bubble detection unit is provided for each ink color. The ink jet recording apparatus described.   Further, when the bubble detecting means continuously detects the bubbles, the ink corresponding to the ink volume in the supply channel is discharged from the nozzle hole regardless of the discharge of the ink by the recovery means. The ink jet recording apparatus according to claim 1, further comprising a large discharge recovery means.

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