JP5902658B2 - Inkjet recording apparatus and inkjet recording method - Google Patents

Description

  The present invention relates to an ink jet recording apparatus that records an image using an ink tank that stores ink in a sealed space so as to apply a negative pressure, and a recording head that can eject ink supplied from the ink tank, and The present invention relates to an ink jet recording method.

  In an inkjet recording apparatus, negative pressure-applied ink is supplied from an ink tank to a recording head, and the recording head uses an ejection energy generating element such as an electrothermal conversion element (heater) or a piezo element from an ejection port. Ink is ejected. Since such a recording apparatus is also used in a small place such as a cash register counter or shelf in a store or on an office desk, it is required to reduce its size.

  In order to reduce the size of the recording apparatus, it is ideal to directly connect the recording head and the ink tank. In order to accommodate a large amount of ink while reducing the size of the ink tank and the recording apparatus, it is advantageous to use a sealed ink tank as the ink tank. As described in Patent Document 1, this sealed ink tank is provided with a flexible bag containing ink, and the bag is energized by a spring or the like in the direction of increasing the internal volume. Some inks supply negative pressure to the ink supplied to the recording head.

  In a sealed ink tank, a flexible bag that contains ink forms a sealed space that communicates only with the recording head. So, for example, when the ink tank runs out of ink and the flexible bag is crushed, and the ink is still left in the recording head, the recording head discharges the ink remaining in the inside, The negative pressure in the recording head will increase. As a result, the ink cannot be discharged satisfactorily, which may cause image recording failure.

JP 2007-313711 A

  An object of the present invention is to provide an ink jet recording apparatus and an ink jet recording method capable of stably ejecting ink in a sealed ink tank and a recording head.

Ink jet recording apparatus of the present invention, capable of ejecting ink from an ink tank containing ink in a sealed space so as to impart a negative pressure in the ink chamber provided inside Ru is supplied into the ink chamber of the recording head and the recording measurement head, and a gas reservoir for the communication with the ink chamber and the pressure allows ejection through the ink chamber and the communicating passage opening and closing means for opening and closing the communication passage, the ink amount in the ink tank measuring means for, and having a control means for communicating the ink chamber with the gas reservoir by the opening and closing means based on the ink amount in the ink tank to be measured by said measuring means.

According to the present invention, the ink in the sealed ink tank and the recording head can be stably ejected.

1 is a schematic front view of an ink jet recording apparatus according to an embodiment of the present invention. FIG. 2 is a block diagram of a control system of the ink jet recording apparatus of FIG. 1. FIG. 2 is a schematic configuration diagram of an ink supply system in the ink jet recording apparatus of FIG. 1. FIG. 4 is an enlarged sectional view of an ink tank and a recording head in FIG. 3. FIG. 4 is an enlarged view of an ink holding member in FIG. 3. FIG. 4 is a flowchart for explaining negative pressure relaxation processing by the ink supply system of FIG. 3. FIG. It is explanatory drawing of operation | movement of the ink supply system in the negative pressure relaxation process of FIG. FIG. 6 is an explanatory diagram of a relationship between ink consumption and negative pressure in a recording head. It is a schematic block diagram of the principal part in other embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. The recording apparatus of this embodiment is an application example as a full-line type inkjet recording apparatus.

  FIG. 1 is an explanatory diagram of a conceptual configuration example of a full-line type ink jet recording apparatus (hereinafter also referred to as “printer”) 110.

  The printer 110 is connected to a host device 120 such as a personal computer, and image information and the like are sent from the host device 120 to the printer 110. In the printer 110, four recording heads 22 (22K, 22C, 22M, 22Y) capable of ejecting ink are arranged so as to be aligned in the conveyance direction (arrow A direction) of the roll paper P as a recording medium. The recording heads 22K, 22C, 22M, and 22Y are recording heads for ejecting black, cyan, magenta, and yellow ink, respectively. Each recording head 22 is configured to eject corresponding ink from a plurality of ejection ports using ejection energy generating elements such as electrothermal conversion elements (heaters) and piezo elements. In the case of using an electrothermal conversion element, the ink can be foamed by the heat generation, and the ink can be ejected from the ejection port using the foaming energy. These discharge ports are arranged in a direction intersecting (in the present example, orthogonal) with the conveyance direction of the arrow A. These recording heads 22 are so-called long line heads, and the recording heads 22K, 22C, 22M and 22Y are arranged side by side in the direction of the arrow A in the conveying direction. The lengths of these recording heads 22 are slightly longer than the maximum width of recording media that can be recorded by the printer 110 (the length in the direction perpendicular to the paper surface of FIG. 1). The recording heads 22 are positioned at predetermined recording positions during the image recording operation.

  A recovery unit 400 is incorporated in the printer 110 for the recovery operation of the recording head 22K (operation for maintaining a good ink discharge state). The recovery unit 400 includes a capping mechanism 50 for removing ink from the ejection port formation surfaces (ejection port formation surfaces) of the respective recording heads 22K, 22C, 22M, and 22Y. The capping mechanism 50 is provided independently for each recording head 22K, 22C, 22M, 22Y. The capping mechanism 50 includes a wiper for wiping the discharge port forming surface, a wiper holding member for holding the wiper, an ink removing member for removing ink adhering to the wiper, and a cap closely contacting the discharge port surface. Is provided.

  The roll paper P is supplied from the supply unit 25 and is conveyed in the direction of arrow A by the conveyance mechanism 26 incorporated in the printer 110. The transport mechanism 26 includes a transport belt 26a for placing and transporting the roll paper P, a transport motor 26b for rotating the transport belt 26a, and a roller 26c for applying tension to the transport belt 26a. The conveyance mechanism 26 may be configured to convey the roll paper P using a conveyance roller, or may constitute a unitized conveyance unit.

  When an image is recorded on the roll paper P, after the recording start position on the roll paper P being conveyed reaches below the recording head 22K, a plurality of discharges in the recording head 22K is performed based on the recording data (image information). Black ink is selectively ejected from the outlet. Similarly, each color ink is ejected in the order of the recording head 22C, the recording head 22M, and the recording head 22Y to record a color image on the roll paper P. The printer 110 includes an ink tank 28 (28K, 28C, 28M, 28Y) that supplies ink to each recording head 22 (22K, 22C, 22M, 22Y). Further, the printer 110 is provided with various pumps for performing ink supply operation and recovery operation to the respective recording heads 22K, 22C, 22M, and 22Y.

  FIG. 2 is a block configuration diagram of the control system of the printer 110.

  Information such as recording data and commands transmitted from the host PC 120 is received by the CPU 100 via the interface controller 102. The CPU 100 is an arithmetic processing unit that performs overall control of the printer 110 such as reception of recording data of the printer 110, recording operation, handling of the roll paper P, and the like. After analyzing the received command, the CPU 100 renders image data of each color component of the recording data by developing a bitmap on the image memory 106.

  When recording an image, first, the capping motor 122 and the head lifting / lowering motor 118 are driven and controlled via the output port 114 and the motor drive unit 116, and the respective recording heads 22 are separated from the corresponding capping mechanism 50 for recording. Move to position. The capping motor 122 is a motor for moving the capping mechanism 50 in the directions of arrows B1 and B2 in FIG. 1, and the head elevating motor 118 is for elevating the recording head 22 in the directions of arrows C1 and C2 in FIG. Motor. Thereafter, a drive motor (not shown) for feeding the roll paper P, a transport motor 26b for transporting the roll paper P at a constant speed, and the like are driven and controlled via the output port 114 and the motor drive unit 116. The roll paper P is conveyed in the direction of arrow A. The timing (recording timing) at which ink starts to be ejected onto the roll paper P conveyed at a constant speed is determined based on the detection timing of the leading edge of the roll paper P by a leading edge detection sensor (not shown). . In synchronism with the conveyance of the roll paper P, the CPU 100 sequentially reads out the recording data corresponding to each ink color from the image memory 106, and the corresponding recording heads 22 </ b> K and 22 </ b> C via the recording head control circuit 112. , 22M, 22Y. The valve 17, the valve 20, and the valve 33 are connected to the CPU 100, and the CPU 100 performs an opening / closing operation. The ink detection sensor 24 is connected to the CPU 100, and based on the output from the ink detection sensor 24, the CPU 100 determines whether or not there is a predetermined amount of ink in a liquid chamber to be described later.

  The CPU 100 executes various processes including a negative pressure relaxation process (see FIG. 6), which will be described later, based on a processing program stored in the program ROM 104. The program ROM 104 stores processing programs and tables corresponding to the control flow. The work RAM 108 is used as a working memory. The CPU 100 drives and controls the pump motor 124 via the output port 114 and the motor driving unit 116 during the cleaning operation and the recovery operation of the respective recording heads 22 so as to pressurize and suck ink.

  FIG. 3 is an explanatory diagram of an ink supply system between the ink tank 28 and the recording head 22, and FIG. 4 is an enlarged sectional view of the ink tank 28 and the recording head 22.

  The ink tank 28 is a sealed ink tank that forms a substantially sealed space in which the liquid chamber 6 inside communicates with the outside only through the joint portion 5, and the liquid chamber 6 that forms the sealed space has at least one. The part is formed of a flexible member. The liquid chamber 6 is provided with a spring 7A that urges the liquid chamber 6 in an expanding direction. A predetermined negative pressure is generated in the liquid chamber 6 by the spring 7A. Therefore, the ink tank 28 stores the ink in the sealed space so as to apply a negative pressure. The spring 7A of this example urges the liquid chamber 6 from the inside toward the outside via the pressure plate 7B so as to expand the internal space of the liquid chamber 6. A negative pressure generating portion is formed by the spring 7A and the pressure plate 7B. A non-woven filter 8 is attached to the joint portion 5.

  The filter 13 and the ink holding member 14 are attached to the joint portion 31 of the recording head 22. The filter 13 is formed of a SUS mesh. The mesh has a structure in which metal fibers are woven, and the average width of the eyes (ink conduction part) of the filter 13 is about 10 μm. The filter 13 has such fine eyes to prevent foreign dust from entering the recording head 22. As shown in FIG. 5, the ink holding member 14 has a plurality of cylindrical flow paths 14A formed therein, and the inner diameter of the flow paths 14A is about 1.0 mm. When the filter 8 on the ink tank 28 is pressed against the filter 13 on the recording head 22 side, the recording head 22 and the ink tank 28 are connected, and the liquid chamber (ink chamber) 6 of the ink tank 28 is the recording head. The 22 liquid chambers (ink chambers) 10 communicate with each other.

  The recording head 22 includes a discharge energy generating element (not shown) for discharging the ink in the liquid chamber 10 from the discharge port 9. As the discharge energy generating element, an electrothermal conversion element (heater), a piezoelectric element, or the like can be used. When the electrothermal converter is used, the ink can be foamed by the generated heat, and the ink can be ejected from the ejection port 9 using the foaming energy. Within the liquid chamber 10, there are a space where the ink layer 11 is formed and a space where the air layer 12 is formed, which is located between the ink layer 11 and the ink tank 28.

  The ink introduced from the ink tank 28 into the recording head 22 is held in the flow path 14A of the ink holding member 14, and forms a meniscus of ink at the lower end of the flow path 14A. When ink is ejected from the ejection port 9 of the recording head 22 and the ink in the liquid chamber 10 is consumed, the pressure in the liquid chamber 10 decreases due to the decrease in the ink layer 11 and the increase in the air layer 12. When the inside of the liquid chamber 10 falls below a predetermined pressure, the ink meniscus formed at the lower end of the flow path 14 </ b> A is broken and ink is supplied from the ink tank 28 into the recording head 22. When the inside of the liquid chamber 10 returns to the original predetermined pressure by such supply of ink, the supply of ink from the ink tank 28 into the recording head 22 stops, and an ink meniscus is formed again at the lower end of the flow path 14A. . In this way, ink is supplied from the ink tank 28 into the recording head 22 through the flow path 14A of the holding member 14 so as to eliminate the pressure drop in the liquid chamber 10 due to ink consumption. The flow path 14 </ b> A allows ink supply from the ink tank 28 to the recording head 22 due to a differential pressure between the recording chamber 22 and the liquid chamber 10 in the sealed space of the ink tank 28.

  An ink detection sensor 24 for detecting the height of the ink layer 11 is provided in the liquid chamber 10. The ink detection sensor 24 is provided with two metal electrode plates 24A and 24B in parallel. When the liquid surface of the ink layer 11 is at a position higher than the height of the lower ends of the electrode plates 24A and 24B, the electrode plates 24A and 24B are electrically connected to each other, and the liquid surface of the ink layer 11 is the electrode plates 24A and 24B. When positioned below the lower end of the electrode plate 24A, the electrode plates 24A and 24B are electrically insulated. Based on the electrical change between the electrode plates 24A and 24B, the CPU 100 determines whether the liquid level of the ink layer 11 is equal to or lower than a predetermined height (the lower end positions of the electrode plates 24A and 24B). Whether or not can be detected.

  In addition to the joint portion 31, the recording head 22 is formed with a communication path 15 for communicating with the outside, and a filter 27 is provided at an opening of the communication path 15. The communication path 15 communicates with a buffer chamber (gas storage unit) 16 via a first valve 17 that can be opened and closed. The buffer chamber 16 has a space of about 30 ml and communicates with the pump 18. The pump 18 of this example is a tube pump that can rotate forward and backward. A flow path 19 communicating with the atmosphere is connected to the buffer chamber 16, and the flow path 19 is provided with a second valve 20 that can be opened and closed. A waste ink tank 32 is connected to the pump 18.

  A cap 34 is connected to the buffer chamber 16 via a third valve 33 that can be opened and closed. The cap 34 can be in close contact with the formation surface (ejection port formation surface) of the ejection port 9 in the recording head 22. In a state where the cap 34 is in close contact with the discharge port forming surface and the discharge port 9 is capped, the inside of the cap 34 is sucked by the pump 18 to suck and discharge ink from the discharge port 9 into the cap 34 (suction recovery operation). ). In addition, a preliminary ejection operation for ejecting ink that does not contribute to image recording into the cap 34 from the ejection port 9, and pressurizing the ink in the recording head 22, forcing it into the cap 34 from the ejection port 9. A pressure recovery operation for discharging ink can also be performed. In the pressure recovery operation, the pressurizing force generated by the pump 18 can be applied to the recording head 22 through the buffer chamber 16 and the first valve 17. The ink received in the cap 34 by such a recovery process can be discharged to the waste ink tank 32 through the buffer chamber 16 by the suction force generated by the pump 18.

  Each color ink tank 28 is provided with a storage element 41 (storage unit) capable of storing various information for each color. When the ink tank 28 is attached to the main body of the recording apparatus (apparatus main body) so that the ink tank 28 is connected to the recording head 22, the storage information of the storage element 41 of the ink tank 28 is read from the apparatus main body side. Read by the unit 40. The CPU 100 can perform control based on the read information, and can also store information in the storage element 41 of the ink tank 28.

  When an image with a large amount of ink used is recorded after the ink in the ink tank 28 is exhausted, the ink in the recording head 22 is consumed without being supplied from the ink tank 28 to the recording head 22. It will be. Therefore, the negative pressure in the liquid chamber 10 of the recording head 22 may increase to a level where ink ejection failure occurs. When recording an image with a large amount of ink used, there are cases where the image size for one page on the roll paper P is large, and the recording density of the image for one page is high. The same applies to the case where a sheet of one page is used as the recording medium.

  In the case of this example, by performing the negative pressure relaxation process, the increase in the negative pressure in the liquid chamber 10 of the recording head 22 is suppressed even in the recording operation after the ink in the ink tank 28 runs out. It is possible to maintain a good discharge state and to record a high-quality image.

  FIG. 6 is a flowchart for explaining the negative pressure relaxation process, and FIG. 7 is an explanatory view of the adjustment state of the negative pressure in the recording head 22 in the negative pressure relaxation process.

  The recording apparatus counts the number of ink ejections from the recording head 22 during the recording operation based on the recording data, thereby sequentially measuring and accumulating the ink consumption after starting to use the ink tank 28. Furthermore, by adding the ink consumption by the recovery operation (including suction recovery operation, preliminary ejection operation, and pressure recovery operation) to the ink consumption by such a recording operation, more accurate ink consumption can be obtained. Consumption can be measured. The ink consumption calculated in this way is stored in a storage element provided in the ink tank 28. Therefore, the storage element stores the cumulative consumption amount D of ink in the ink tank 28 provided with the storage element. When the cumulative consumption amount D of ink stored in the storage element becomes equal to or greater than a predetermined amount, it is determined that there is no ink in the ink tank 28, and the process proceeds to the negative pressure relaxation mode in FIG.

  When the mode shifts to the negative pressure relaxation mode, first, the ink consumption D1 necessary for recording the next one page image (unit recording image) on the roll paper P is predicted based on the recording data (step S1). . Specifically, the number of ink ejections for recording an image for the next page is counted based on the recording data, and based on the count value and the ink amount per ejection of ink. The consumption D1 is predicted. Next, it is determined whether the total consumption amount (D + D1) of the consumption amount D1 and the cumulative consumption amount D described above is equal to or greater than a predetermined amount DA (step S2). The predetermined amount DA is an amount by which the negative pressure in the liquid chamber 10 of the recording head 22 does not increase until the satisfactory ink ejection state cannot be maintained even if the total consumption amount (D + D1) reaches that level. It is. However, when the total consumption (D + D1) exceeds the predetermined amount DA to some extent, the negative pressure in the liquid chamber 10 may increase to such an extent that a good ink ejection state cannot be maintained. By associating the number of ink ejections with the amount of ink consumption, the total consumption amount (by determining whether the number of ink ejections after the transition to the negative pressure relaxation mode has reached the specified number of times) It can also be determined whether D + D1) is greater than or equal to a predetermined amount DA.

  When the total consumption (D + D1) is less than the predetermined amount DA, an image for the next page is recorded (step S3). On the other hand, when the total consumption (D + D1) is equal to or greater than the predetermined amount DA, a series of processes for communicating the liquid chamber 10 of the recording head 22 with the buffer chamber 16 is performed (steps S11, S12, S13, S14). That is, first, as shown in FIG. 7A, the second valve 20 is opened while the first and third valves 17 and 33 are closed, and the pressure in the buffer chamber 16 is set to atmospheric pressure (step S11). Then, after closing the second valve 20 as shown in FIG. 7B (step S12), the pump 18 is rotated in the direction of discharging the air in the buffer chamber 16 as shown in FIG. 7C. (Step S13), the inside of the buffer chamber 16 is set to a negative pressure. Thereafter, the negative pressure in the buffer chamber 16 is made equal to the negative pressure in the liquid chamber 10 of the recording head 22, and then the first valve 17 is opened as shown in FIG. 7D (step S14). Then, after the buffer chamber 16 and the liquid chamber 10 of the recording head 22 are communicated in this way, an image for the next one page is recorded (step S3). The internal pressure of the buffer chamber 16 is equivalent to the negative pressure in the liquid chamber 10 of the recording head 22 based on, for example, the rotation amount of a tube pump as the pump 18 or a detection signal of a sensor that detects the pressure in the buffer chamber 16. Can be adjusted. By adjusting the pressure in the buffer chamber 16 in this way, the pressure fluctuation in the liquid chamber 10 when the buffer chamber 16 and the liquid chamber 10 of the recording head 22 communicate with each other can be reduced.

  As described above, the air chamber 12 in the liquid chamber 10 of the recording head 22 is formed to cover the region including the inside of the buffer chamber 16 by communicating the buffer chamber 16 with the liquid chamber 10 of the recording head 22. The That is, the volume of the space where the air in the liquid chamber 10 of the recording head 22 is present is substantially enlarged. Therefore, in the recording operation (step S4) after the ink in the ink tank 28 is exhausted, the ink in the liquid chamber 10 is suppressed by the substantially expanded air in the liquid chamber 10 and the ink is suppressed. It is possible to maintain a good discharge state.

  FIG. 8 is an explanatory diagram of the relationship between the ink consumption associated with the recording operation after the total consumption (D + D1) is equal to or greater than the predetermined amount DA and the negative pressure in the liquid chamber 10 of the recording head 22. is there. As in this example, by substantially expanding the space in the liquid chamber 10, the increase in the negative pressure in the liquid chamber 10 can be suppressed to a small value as shown by the curve E. When the inside of the liquid chamber 10 of the recording head 22 is not communicated with the buffer chamber 16, that is, when the space in the liquid chamber 10 is not substantially expanded, the negative pressure in the liquid chamber 10 as shown by the curve F. Rose.

  After the recording operation (step S3), it is determined whether or not the ink detection sensor 24 is conductive, that is, whether or not the ink amount in the recording head 22 exceeds a predetermined amount (step S4). If the ink detection sensor 24 detects ink, it is determined whether or not recording of all images has been completed (step S5). If the image recording is not completed, the consumption amount (D + D1) is updated as the cumulative consumption amount D (step S6), and then the processing described above is repeated by returning to the previous step S1. If the image recording is completed, the negative pressure relaxation process in FIG. 6 is terminated.

  In step S4, if the ink detection sensor 24 does not detect ink, that is, if the amount of ink in the recording head 22 is less than or equal to a predetermined amount, the pressure in the liquid chamber 10 of the recording head 22 is reduced by a suction operation (step S4). S7). As a result, the ink in the ink tank 28 is sucked into the liquid chamber (ink chamber) of the recording head 22 as much as possible. Specifically, the first valve 17 is opened, and the pump 18 is rotated in a direction to reduce the pressure in the liquid chamber 10 of the recording head 22. Thereafter, it is determined again whether or not the ink detection sensor 24 detects ink (step S8). If ink is detected, the process proceeds to step S6, and if it is not detected, the user is informed of the ink tank 28. Exchange is urged (step S10).

  As described above, when the ink in the sealed ink tank runs out, the space in the liquid chamber of the recording head is substantially enlarged, and the amount of air in the space is substantially increased. Accordingly, it is possible to suppress an increase in the negative pressure in the liquid chamber of the recording head during the subsequent recording and maintain a good ink ejection state. As a result, the ink in the ink tank and the recording head can be used to the maximum without causing image recording failure. Further, as described above, the relatively small space in the liquid chamber of the pre-recording head before being substantially enlarged reacts appropriately with the pressure drop in the liquid chamber and records from the ink tank through the ink holding member. Ink can be reliably supplied into the head. In this way, during normal times when ink is present in the ink tank, a relatively small space in the recording head reacts appropriately to the pressure drop in order to reliably supply ink. On the other hand, when the ink in the ink tank runs out, the space in the print head that is practically enlarged alleviates the increase in negative pressure in the print head.

(Other embodiments)
As shown in FIG. 9, a plurality of recording heads may be commonly connected to one buffer chamber. The other parts are the same as those in the above-described embodiment, and thus the description thereof is omitted. In this example, four recording heads 22 (22Y, 22M, 22C, 22K) are connected to one buffer chamber 16 through corresponding first valves 17 (17Y, 17M, 17C, 17K). Has been. When the ink in the ink tank 28Y runs out, the CPU 100 opens the first valve 17Y so that the liquid chamber of the recording head 22Y and the buffer chamber 16 are substantially expanded so as to substantially expand the liquid chamber of the recording head 22Y. Communicate. The same applies to the other recording heads 22M, 22C, and 22K.

10 Liquid chamber (ink chamber)
16 Buffer chamber (gas storage part)
17 1st valve (opening and closing means)
22 Recording Head 28 Ink Tank 110 Printer (Inkjet Recording Device)

Claims (10)

Ink and recording head capable of ejecting from the ink tank Ru is supplied into the ink chamber for storing ink in a sealed space so as to impart a negative pressure in the ink chamber provided inside of the recording head,
A gas reservoir to the pressure allows ejection of communicating with the ink chamber through the ink chamber and the communicating path,
Opening and closing means for opening and closing the communication path;
Measuring means for measuring the amount of ink in the ink tank;
Control means for communicating the gas reservoir and the ink chamber by the opening and closing means based on the ink amount in the ink tank measured by the measuring means;
An ink jet recording apparatus comprising: It said control means is an ink jet recording apparatus according to claim 1, characterized in that opening the communication path on the basis of the ink amount and the ink amount required for the next recording of the ink tank. 3. The ink jet recording apparatus according to claim 2, wherein the ink amount necessary for the next recording is set based on an image for one page recorded on a recording medium.   The inkjet recording apparatus according to claim 1, further comprising a pressure adjusting unit configured to adjust an internal pressure of the gas storage unit. A detecting means for detecting the amount of ink in the ink chamber,
Decompression means for decompressing the ink chamber so that ink is sucked from the ink tank into the ink chamber of the recording head when the amount of ink detected by the detection means is equal to or less than a predetermined amount;
The inkjet recording apparatus according to any one of claims 1 to 3 , further comprising: It said pressure reducing means is an ink jet recording apparatus according to claim 5, characterized in that depressurizing the ink chamber through the gas retention portion.   A flow path is provided between the ink tank and the recording head to allow ink to be supplied from the sealed space to the ink chamber due to a differential pressure between the sealed space and the ink chamber. An ink jet recording apparatus according to any one of claims 1 to 6. 8. The ink jet recording apparatus according to claim 1 , wherein ink chambers of a plurality of the recording heads communicate with one gas storage unit via the individual communication paths. 9. . Ink contained in the closed space of the ink tank so as to impart a negative pressure in the ink chamber provided inside of the recording head to supply the ink within a recording head, the recording head ejects ink in the ink chamber An ink jet recording method for recording an image by
In the gas storage section, when the image is recorded after the ink amount in the ink tank becomes equal to or less than a predetermined amount , the ink chamber communicates with the ink chamber so that the ink chamber has a pressure capable of discharging ink. the ink jet recording method which comprises causing the communication. When communicating the gas reservoir to the ink chamber, the ink jet recording method according to claim 9, wherein the pressure of the gas reservoir to the pressure and substantially the same the ink chamber.

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