JP2000301732A - Ink jet recording apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To discharge a gas remaining in an ink tank connected to a recording head by a simple mechanism without increasing the number of pumps or the like. SOLUTION: A recording head 1 which discharges ink from a discharge opening 6 thereby recording to a recording medium, and a sub tank 2 connected to the recording head 1 are mounted to a carriage 3. The sub tank 2 is connected to a main tank 4 via a feed tube 5. A suction cap unit 41 and a tube pump 50 constituting a suction means for sucking ink from the discharge opening 6 of the recording head 1 are set below the recording head 1 and sub tank 2 which are moved to a predetermined position by the carriage 3. The suction means 41 and 50 are constituted to be able to discharge outside the air in the sub tank 2 from an air vent hole 19 set to a lower part of the sub tank 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet recording apparatus, and more particularly, to an ink jet recording apparatus for supplying ink from a main tank holding a large amount of ink to a recording head via a sub tank.

[0002]

2. Description of the Related Art In recent years, ink jet recording apparatuses for recording using ink have become widespread as printers and copiers for personal computers. Since the inkjet recording device is inexpensive and capable of full-color recording,
The demand is growing.

In recent years, ink-jet recording apparatuses have been used even for plotters that record photographic images on large sheets such as A1 and A0 plates.

[0004] Ink jet recording is also being applied to multi-tone image recording for medical use such as X-ray film and CT scan image. In such a medical image recording apparatus, by combining a plurality of types of inks having different densities and recording the ink twice and three times, it is possible to express gradations far greater than the number of types of ink. It is possible.

However, since the plotter and the recording apparatus for medical images use a large amount of ink, if the ink tank is mounted on the carriage together with the recording head, the ink tank must be replaced frequently, which is inconvenient. is there.

Accordingly, an ink supply system such as that shown in FIG. 1 is generally used in an ink jet recording apparatus that consumes a large amount of ink. FIG. 7 is a diagram showing a schematic configuration of an ink supply system in a conventional inkjet recording apparatus.

As shown in FIG. 7, a recording head 301 is mounted on a carriage 302 movable with respect to the apparatus main body. Reference numeral 303 denotes a main tank fixed to the apparatus main body. When the ink becomes low, the ink is supplied to the ink tank 303. The recording head 301 and the main tank 303 are connected by an ink flow path 304 including a tube, a joint, and the like. The carriage 302 reciprocates at the time of printing.
By using a flexible tube (for example, a silicon tube, a polyethylene tube, or the like) for at least a part of 4, the movement of the carriage 302 is not hindered. The main tank 303 is provided with an atmosphere communication hole 305, and the inside of the main tank 303 is communicated with the atmosphere. Therefore, when ink is ejected from the recording head 301, the ink flows from the main tank 303 to the ink flow path 3.
After 04, the recording head 301 is replenished. The pressure in the print head 301 must be maintained in a negative pressure state so that ink does not leak from the ejection port 306. The pressure inside the print head 301 is determined by the ink level H1 of the main tank 303, and H1 is the print head 3
20 to 100 mm higher than the height H0 of the discharge port 306 of No. 01
It is preferable to provide it at a lower position.

When this method is used, ink supply can be realized with a very simple structure. However, since a flexible tube used for the ink flow path 304 is made of rubber or resin, a slight amount of gas is used. It has permeability. Since the inside of the tube has a negative pressure similarly to the inside of the recording head 301, air gradually enters from the atmosphere through the tube wall into the tube, and bubbles are generated. When the air bubbles flow into the recording head 301, normal ink droplets cannot be ejected, and printing defects occur. On the other hand, when H1 is brought close to H0 in order to reduce the generation of air bubbles as much as possible, changes in the temperature, impact, vibration, etc. cause the ejection port 30 of the recording head 301 to change.
6 easily leaks ink. Even if it is possible to prevent the air from gradually entering from the atmosphere through the tube wall, the air dissolved in the ink may grow into bubbles in the tube and the sub tank.
Therefore, even if bubbles are generated, the bubbles are generated by the recording head 301.
An ink supply system as shown in FIG. 8 has been proposed so as not to enter the inside.

FIG. 8 is a diagram showing a schematic configuration of another ink supply system in a conventional ink jet recording apparatus.

In FIG. 8, reference numeral 201 denotes a print head, and reference numeral 202 denotes a sub-tank for storing ink to be supplied to the print head 201. The recording head 201 and the sub tank 202 are mounted on a carriage 203 movable with respect to the apparatus main body. Reference numeral 204 denotes a main tank fixed to the apparatus main body. When the amount of ink is low, the main tank 204 is supplied with ink.
The sub-tank 202 and the main tank 204 are composed of two ink flow paths 205 and 20 formed of a tube, a joint, and the like.
6 are connected. The first ink flow path 205 stores the ink stored in the main tank 204 in the sub tank 2.
02, and the second ink flow path 206 returns the ink stored in the sub tank 202 to the main tank 204. A so-called piston type pump 207 is provided in the middle of the second ink flow path 206. The ink in the sub tank 202 is transferred to the main tank 204 by the pump 207. The main tank 204 is provided with an atmosphere communication hole 208, and the inside of the main tank 204 is communicated with the atmosphere. However, since the sub tank 202 has a closed structure, the inside of the sub tank 202 is communicated with the atmosphere. Not.

Therefore, when the pump 207 is driven,
The ink in the sub tank 202 is supplied to the second ink flow path 206
The ink in the main tank 204 is sucked into the sub tank 202 through the first ink flow path 205 while being sent to the main tank 204 through the main tank 204. In this way, the circulation of ink between the sub tank 202 and the main tank 204 is performed.

The pressure in the sub-tank 202 must be maintained at a negative pressure so that ink does not leak from the ejection openings of the recording head 201. The pressure in the sub tank 202 is determined by the ink level H1 of the main tank 204, and it is preferable that H1 be provided at a position lower by about 20 to 100 mm than the height H0 of the chip surface (ejection port surface) of the recording head 201. Reference numeral 209 denotes the main tank 20
4 shows a liquid level sensor provided in the inside of FIG. When the sensor detects that the ink level has become equal to or lower than the position of the liquid level sensor 209, the user is urged to supply ink by a display LED (not shown) or the like.

According to such a configuration, air bubbles are generated in the first ink flow path 205 in the same manner as in the prior art shown in FIG. The ink is discharged into the main tank 204 through the second ink flow path 206. Therefore, air bubbles generated in the middle do not enter the inside of the recording head 201, and the occurrence of printing failure is prevented.

[0014]

However, in the above-described plotters and medical image recording apparatuses, the types of ink tend to increase in order to realize more complicated gradation expression. For example, in a photographic color plotter, it has been proposed to use inks of six or more colors, such as adding cyan, magenta, and the like with low density in addition to normal cyan, magenta, yellow, and black. Even in a medical image recording apparatus, in order to produce an image that requires 1000 or more gradations, such as an X-ray image, at least a 6
Requires black ink of color. For example, when six types of inks are used, six ink supply systems are required, and 6 × 2 = 12 between the sub tank and the main tank.
Two ink channels are required.

On the other hand, in the above description, the intrusion of air from the outside into the tube has been described. On the contrary, it has also been confirmed that moisture and solvent in the ink evaporate to the outside through the tube wall. Therefore, the greater the number of ink flow paths between the sub tank and the main tank, the greater the amount of water and solvent that evaporate, and the density of the ink changes. For multi-tone images, especially images with 1000 or more tones,
If the density of each ink changes, accurate gradation expression cannot be performed.

If a piston type pump or a gear pump is used, a total of six pumps are required, one for each color.
As for the pump, if a so-called tube pump that sends liquid by handling a tube with a plurality of rollers is used,
It is possible to circulate multiple colors of ink with a single pump, but since the same part of the tube is handled, if used over a long period of time, the dust inside the tube and the oil and fat components contained in the tube material However, such impurities are mixed in the ink and clog the ejection openings of the recording head, resulting in poor printing.

Therefore, the present inventor has proposed in Japanese Patent Application No. 10-128.
No. 959 proposes that a gas accumulated in an ink tank connected to a recording head is exhausted by a suction pump when the carriage is at a home position. According to the present invention, it is possible to provide an ink supply system that prevents bubbles generated in an ink flow path from entering a print head without increasing the number of ink flow paths, and that does not include a pump in the ink flow path. It became possible.

However, in the invention proposed in the above-mentioned application, a suction pump for discharging air from the ink tank connected to the recording head, and a mechanism for contacting or retracting the joint of the suction pump with the ink tank. Is required. Therefore, problems such as an increase in cost due to an increase in the number of parts, an increase in the size of the apparatus, and an increase in power consumption have become apparent. In general, an ink jet apparatus is provided with a recovery unit for forcibly discharging ink from the ink ejection port in order to eliminate clogging of the ink ejection port of the recording head. The ink discharge operation by the recovery means is usually performed using a suction operation by a pump.

In view of the above, it is an object of the present invention to provide an ink jet recording apparatus for exhausting gas accumulated in an ink tank connected to a recording head by a simple mechanism without increasing the number of pumps and the like. This is the purpose of 1.

A second object of the present invention is to provide an ink jet recording apparatus capable of switching between a head recovery operation and an exhaust operation in an ink tank connected to a recording head without providing any other mechanism or means. It is to provide.

[0021]

In order to achieve the above object, an ink jet recording apparatus according to the present invention comprises: a recording head for discharging ink from a discharge port to perform recording on a recording medium; and a second recording head connected to the recording head. 1 ink tank and a second ink tank connected to the first ink tank via a tube.
An ink tank, and suction means for sucking ink from a discharge port of the recording head. The first ink tank has an exhaust hole for exhausting gas in the first ink tank to the outside. An ink jet recording apparatus provided, wherein the gas in the first ink tank is exhausted to the outside from the exhaust hole by the suction means.

In the tube connecting the first ink tank and the second ink tank, air enters from the outside through the wall of the tube, and bubbles are generated. Since the air bubbles also flow into the first ink tank together with the ink, the ink level in the first ink tank gradually decreases. Then, the gas in the first ink tank is exhausted to the outside from the exhaust hole using the suction means, so that the ink of the volume of the exhausted gas is replenished from the second ink tank into the first ink tank. Then, the ink level in the first ink tank returns to the initial level. As described above, according to the present invention, since the gas in the first ink tank is exhausted by using the suction means for sucking the ink from the ejection port of the recording head, a simple operation can be performed without increasing the number of pumps and the like. The mechanism makes it possible to exhaust gas accumulated in the ink tank connected to the recording head.

Further, the exhaust hole may be provided with a valve mechanism which is opened when the suction operation of the gas from the exhaust hole is started by the suction means.

The recording head and the first ink tank are mounted on a carriage that scans in the width direction of the recording medium, and the discharge port and the opening of the exhaust hole are arranged along the scanning direction of the carriage. By controlling the moving distance of the carriage by adjoining each other, the recovery operation of the recording head by the suction means and the exhaust of the ink tank can be performed without any other mechanism or means. It is possible to switch the operation from the exhaust operation through the hole.

[0025]

Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a schematic top view showing an embodiment of the ink jet recording apparatus of the present invention. FIG. 2 is a diagram for explaining an ink supply path and a suction unit for one recording head of the ink jet recording apparatus shown in FIG.

In FIG. 1, a carriage 3 is provided on a guide rail 31 supported by two side plates 30a and 30b spaced from each other so as to be slidable in the direction of arrow A in the figure. The mechanism for moving the carriage 3 may be the same as that used in a general printing apparatus, and thus the description thereof will be omitted. As shown in FIG. 2, the carriage 3 is equipped with a recording head 1 for discharging ink, and a sub-tank 2 as a first ink tank for holding ink to be supplied to the recording head 1. The recording head 1 and the sub-tank 2 are directly connected without a tube, and are mounted on the carriage 3 by six each.

Each recording head 1 has a nozzle having an ejection port 6 for ejecting ink, and a heating element (not shown) for heating the ink in the nozzle to boil the ink inside the nozzle. are doing. When the heating element is driven to cause film boiling of the ink in the nozzle, bubbles are generated in the nozzle, and the ink is discharged from the discharge port 6 by the pressure generated by the growth of the bubble.

The recording medium on which recording is performed by the recording head 1 is transported by the recording medium transport mechanism 60 to a position facing the discharge port 6.

The sub tank 2 is connected to a main tank 4 as a second ink tank by a supply tube 5 having flexibility. The supply tubes 5 are bundled and protected by a cover member 33 having flexibility. Therefore, the carriage 3 reciprocates along the guide rail 31 during the recording operation, but the supply tube 5
Is flexible and does not hinder its movement.

The main tank 4 is fixed to the main body,
The content of the main tank 4 is sufficiently larger than the content of the sub-tank 2. Even if the ink in the sub tank 2 is consumed, the ink is automatically replenished from the main tank 4, so that the size of the sub tank 2 can be reduced.

The ink stored in the main tank 4 is temporarily held in the sub tank 2 and supplied to the recording head 1. The direction perpendicular to the direction of movement of the carriage 3 by the recording medium transport mechanism 60 (the width direction of the recording medium)
The recording head 1 is controlled based on a recording signal sent from a control unit (not shown) of the recording apparatus main body while repeating the conveyance of the recording medium at a predetermined pitch and the reciprocating movement of the carriage 3.
By driving these heating elements, ink is ejected from the recording head 1 and recording is performed on a recording medium. If each of the main tanks 4 contains an ink of a different color, color printing can be performed, and if inks having different densities are stored, gradation printing can be performed. When the remaining amount of ink in the main tank 4 decreases with recording, ink can be supplied to the main tank 4.

Further, the ink jet recording apparatus of this embodiment is provided with a head recovery unit 40 as suction means for maintaining the discharge performance of the recording head 1.
The head recovery unit 40 is installed at a position facing the recording head 1 closest to the recording medium transport mechanism 60, within the moving range of the carriage 3 and outside the reciprocating operation range of the carriage during the recording operation. The head recovery unit 40 prevents a suction cap unit 41 for sucking ink from the ejection ports of the recording head 1, a pump 50 for generating the suction force, and other ejection ports of the recording head 1 from being clogged. Protective cap 45, wiper blade (not shown) for wiping the ink ejection surface of recording head 1
It is composed of The suction cap unit 41 and the protection cap 45 are configured to be retractable by a mechanism (not shown) so as not to hinder the movement of the carriage 3 during non-operation.

Next, the ink supply path from the main tank 4 to the recording head 1 and the head recovery unit 40 will be described with reference to FIG.

The main tank 4 is provided with an atmosphere communication hole 7, and the inside of the main tank 4 is communicated with the atmosphere. Further, the inside of the sub tank 2 is sealed except for a connection portion of the supply tube 5, a connection portion with the recording head 1, and a connection portion with a check valve 9 described later, so that a substantially sealed space is formed. I have. Therefore, when the ink is ejected from the recording head 1, the ink is supplied from the main tank 4 to the sub tank 2 via the supply tube (ink flow path) 5.

The pressure in the recording head 1 is determined by the ink level H1 of the main tank 4 as in the prior art.
The nozzle is maintained at a negative pressure state by being provided at a position lower than the height H0 of the discharge port 6 by about 20 to 100 mm. A liquid level sensor 8 is provided inside the main tank 4. When the liquid level sensor 8 detects that the ink level has fallen below the position of the sensor 8, the recording device displays an unillustrated display LE.
The user is urged to supply ink by D or the like.

Inside the sub-tank 2, two liquid level sensors 12, 13 are provided. Lower liquid level sensor 12
Is provided for detecting that the liquid level of the ink in the sub tank 2 is too low, and the upper liquid level sensor 13 is provided for detecting that the liquid level of the ink is too high. On the other hand, the sub tank 2
A check valve 9 that allows air to flow only in a direction in which air inside is discharged to the outside, a so-called check valve 9, is provided.

The pump for generating the suction force of the suction cap unit 41 in the head recovery unit 40 is a so-called tube pump 50.
Handle the tube 57 connected to the
The suction cap unit 41 is configured to generate a negative pressure.

The tube pump 50 has a roller holder 52 that is rotated about a rotary shaft 53 by a pump driving source (not shown), and is arranged concentrically with the roller holder 52 so that the tube pump 50 can freely rotate about a roller rotary shaft 54. The roller 5 is rotated by a compression spring 56 to squeeze a tube 57 between the roller 51 and six rollers 51 provided to rotate.
And an urging member 55 urged toward 1.

When the roller holder 52 is rotated in the direction indicated by arrow B by a pump driving source (motor), the tube 57 is handled by the revolving motion of the roller 51, and the inside of the tube 57 becomes a negative pressure. Unit 4
From 1, ink or air is sucked.

Next, details of the suction cap unit 41 will be described with reference to FIGS. FIG.
FIG. 4 shows the recording head, sub-tank, and suction cap unit shown in FIG. 2 in a state where the suction cap is in close contact with the discharge port of the recording head. FIG. 4 shows the recording head, sub-tank, and suction cap unit shown in FIG. FIG. 4 is a diagram illustrating a state in which a suction cap is separated from a discharge port of a recording head.

The suction cap unit 41 includes a rubber suction cap 42, a sealing cap 43, and a cap holder 44 for holding the suction cap 42 and the sealing cap 43. The cap holder 44 is connected to a tube pump 50 (see FIG. 2) via a tube 57, and the through hole of the cap holder 44 allows the space in the suction cap 42 to communicate with the inside of the tube 57. Further, an absorber 46 is provided in the suction cap 42 so as to allow gas and liquid to pass therethrough.

Next, the operation of sucking ink from the ejection port 6 of the recording head 1 by the suction cap unit 41 will be described with reference to FIGS.

The suction cap unit 41 can be moved in the direction of arrow C by a mechanism (not shown), and ink is sucked from the ejection port 6 of the recording head 1 at the position shown in FIG. The position shown in FIG. 4 is a retracted position and does not hinder the movement of the carriage 3 (see FIG. 2 and the like). In the state shown in FIG. 3, the suction cap 42 completely covers the discharge port 6, and the entire circumference of the suction cap 42 is pressed against the recording head 1. Therefore, when the pump 50 is operated in this state, the negative pressure in the suction cap 42 gradually increases, ink is sucked from the ejection port 6, and clogging of the ejection port 6 is eliminated and prevented. At this time, since the check valve 9 is closed, the same amount of ink as the ink sucked from the sub tank 2 is replenished from the main tank 4 to the sub tank 2.

Next, details of the check valve 9 will be described with reference to FIG. FIG. 5 is an enlarged view of the check valve shown in FIG.

The check valve 9 is provided so as to close the air vent hole 14 communicating with the exhaust passage 21 of the sub-tank 2 (see FIG. 2). The valve 16 includes a valve holder 17, which moves integrally with the valve 16, a valve 16, and a compression spring 18 for urging the valve holder 17 upward. Housing 1
5 is also provided with an air vent hole 19, and the valve holder 17
Are provided with holes 20a and 20b for communicating the inside of the housing 15 up and down in the figure. In addition,
The exhaust passage 21, the check valve 9, and the air vent hole 19 constitute an exhaust hole for exhausting the air in the sub tank 2 to the outside.

Next, the exhaust operation of the sub tank 2 will be described with reference to FIGS. FIG. 6 is a diagram illustrating the recording head, the sub tank, and the suction cap unit illustrated in FIG. 2 in a state where the suction cap is in close contact with the air vent hole of the check valve.

In the initial state, the sub tank 2 is filled with ink up to the position of the liquid level sensor 13. Each time printing is performed, ink is supplied from the main tank 4 to the sub tank 2 via the supply tube 5. But,
Air gradually enters the supply tube 5 through the flow path wall, and bubbles are generated. The bubbles also flow into the sub-tank 2 together with the ink, so that the ink level in the sub-tank 2 gradually decreases. When detecting that the ink level has dropped to the level sensor 12, the carriage 3
Moves to the home position after a series of printing operations is completed. Immediately thereafter, when the carriage 3 moves toward the center of the apparatus by the distance D and the suction cap unit 41 rises, the suction cap 42 is brought into close contact with the air vent hole 19 of the check valve 6 as shown in FIG. Become.

Next, when the tube pump 50 (see FIG. 2) is operated, the air in the housing 15 of the check valve 9 is sucked little by little, and the inside of the housing 15 becomes a negative pressure. At first, the valve 16 does not open because the pressing force of the compression spring 18 is larger than the negative pressure force in the housing 15. However, when the force due to the negative pressure gradually increases and exceeds the pressing force of the compression spring 18, the valve 16 opens and the sub tank 2
As shown by the arrow in FIG.
1. The air is exhausted from the suction cap 42 into the atmosphere through the holes 20a and 20b of the valve holder 17 and the air vent hole 19. At this time, as shown in FIG. 6, since the ink discharge port 6 of the recording head 1 is closed by the sealing cap 43, as the air in the sub-tank 2 is exhausted, the volume of ink is From the sub-tank 2. When the ink level in the sub-tank 2 reaches the level sensor 13, the tube pump 50 stops, the suction cap unit 41 moves downward by a retracting mechanism (not shown), separates from the recording head 1, and the check valve. 9 is closed again.

As described above, according to the ink jet recording apparatus of the present embodiment, the air in the sub tank 2 is exhausted by using the head recovery unit 40 that sucks the ink from the ejection port 6 of the recording head 1, so that the pump The gas accumulated in the sub-tank 2 connected to the recording head 1 can be exhausted by a simple mechanism without increasing the number.

As shown in FIGS. 2 and 6, the discharge port 6 of the recording head 1 and the air vent hole 19 of the sub tank 2 are provided.
Since the “openings of the exhaust holes” are disposed adjacent to each other along the scanning direction of the carriage 3, the inkjet recording apparatus of the present embodiment controls the movement distance of the carriage 3 to control It is possible to switch between the recovery operation of the recording head 1 by the suction unit and the exhaust operation of the sub-tank 2 without providing the above mechanism or means.

When exhausting all six sub-tanks 2, the sub-tank 2 is first moved to the center of the apparatus by a distance D from the home position to exhaust the sub-tanks 2. , The carriage 3 is moved to the left side of the drawing by a distance corresponding to one sub-tank, and the exhaust of each sub-tank 2 is sequentially performed in the same procedure. Of course, the sequence may be such that only the sub-tank 2 in which the ink level has been detected is exhausted, or even if the level is detected in only one sub-tank 2, the exhaust of all the sub-tanks 2 is performed. May be performed.

Further, in order to shorten the time for exhausting, a plurality of suction cap units 41 may be provided to simultaneously exhaust the plurality of sub-tanks 2.

[0054]

As described above, according to the ink jet recording apparatus of the present invention, the suction means for sucking ink from the discharge port of the recording head allows the first ink tank to be discharged from the exhaust hole provided in the first ink tank. Since the inside gas is exhausted to the outside, the gas accumulated in the ink tank connected to the recording head can be exhausted by a simple mechanism without increasing the number of pumps and the like.

Further, the recording head and the first ink tank are mounted on a carriage that is scanned in the width direction of the recording medium, and the discharge ports and the exhaust holes are arranged adjacent to each other along the scanning direction of the carriage. Accordingly, it is possible to switch between the operation of recovering the recording head by the suction unit and the operation of exhausting from the exhaust hole of the ink tank without providing any other mechanism or means.

[Brief description of the drawings]

FIG. 1 is a schematic top view showing an embodiment of an ink jet recording apparatus of the present invention.

FIG. 2 is a diagram for explaining an ink supply path and a suction unit for one recording head of the inkjet recording apparatus shown in FIG.

FIG. 3 is a view showing the print head, sub-tank, and suction cap unit shown in FIG. 2 in a state where a suction cap is in close contact with an ejection port of the print head.

FIG. 4 is a view showing the recording head, the sub-tank, and the suction cap unit shown in FIG. 2 in a state where the suction cap is separated from an ejection port of the recording head.

FIG. 5 is an enlarged view of the check valve shown in FIG. 2;

FIG. 6 is a diagram illustrating the recording head, the sub tank, and the suction cap unit illustrated in FIG. 2 in a state where the suction cap is in close contact with an air vent hole of a check valve.

FIG. 7 is a diagram illustrating a schematic configuration of an ink supply system in a conventional inkjet recording apparatus.

FIG. 8 is a diagram illustrating a schematic configuration of another ink supply system in a conventional inkjet recording apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Recording head 2 Sub tank 3 Carriage 4 Main tank 5 Supply tube 6 Discharge port 7 Atmospheric communication port 8, 12, 13 Liquid level sensor 9 Check valve 14, 19 Air vent hole 15 Housing 16 Valve 17 Valve holder 18, 56 Compression spring 20a , 20b hole 21 exhaust passage 30a, 30b side plate 31 guide rail 33 cover member 40 head recovery unit 41 suction cap unit 42 suction cap 43 sealing cap 44 cap holder 45 protective cap 46 absorber 50 tube pump 51 roller 52 roller holder 53 rotating shaft 54 roller rotating shaft 55 urging member 57 tube

Claims (3)

[Claims] A recording head configured to discharge ink from a discharge port to perform recording on a recording medium; a first ink tank connected to the recording head; and a first ink tank connected to the first ink tank via a tube. A second ink tank, and suction means for sucking ink from a discharge port of the recording head, wherein the first ink tank is used to exhaust gas in the first ink tank to the outside. An ink jet recording apparatus provided with an exhaust hole, wherein the gas in the first ink tank is exhausted to the outside from the exhaust hole by the suction means. . 2. The ink jet recording apparatus according to claim 1, wherein the exhaust port is provided with a valve mechanism that opens when the suction operation of the gas from the exhaust port is started by the suction unit. 3. The printing head and the first ink tank are mounted on a carriage that scans in the width direction of the printing medium, and the discharge port and the opening of the exhaust hole are arranged along the scanning direction of the carriage. The inkjet recording apparatus according to claim 1, wherein the inkjet recording apparatuses are arranged adjacent to each other.