JP2003001849A - Ink jet recorder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a decrease in printing performance and nozzle clogging by reducing fluctuations in back pressure in a buffer tank 5 during printing operations. SOLUTION: A print head 2 and the buffer tank 5 are mounted on a carriage 4 so as to be movable, and ink is supplied to an ink inflow cylinder 8 of the buffer tank 5 from an ink cartridge 30 in a fixed position via flexible tubes 13 and 31. Ink 24 for a damper is put into a part on the upper side of a dynamic-pressure absorbing tank 20 connected to an opened cylinder 9 communicating with a ceiling wall 7 (a pneumatic part) of the buffer tank 5, and supported appropriately by a meshed filter 22 whose meniscus has resistance to pressure. The fluctuations of the back pressure in the buffer tank 5, which are attendant upon the advance/retreat operations of the ink in the flexible tubes 13 and 31, are absorbed by air bubbles, which pass through the filter 22 so as to be opened to the atmosphere from the ink 24, or the ink 24 which passes through the filter 22 in order to fall into the buffer tank 5.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the structure of an ink jet recording apparatus provided with a print head for supplying ink from an ink tank for printing.

[0002]

2. Description of the Related Art Conventionally, in an ink jet recording apparatus for ejecting and recording an ink on a recording medium based on an input signal, the ink is guided from an ink tank to a plurality of ejection channels of a print head through an ink flow path, It is known that an actuator such as a heating element or a piezoelectric element is selectively driven to eject ink from the tip (nozzle) of an ejection channel. In this type of ink jet recording apparatus, as disclosed in Japanese Patent Application Laid-Open No. 2000-190513, a small serial printer type apparatus has a print head and ink on a carriage that reciprocates with respect to a recording medium. Although there are those equipped with an ink cartridge as a supply source, the moment of inertia at the time of stopping and returning at the moving end of the carriage becomes large in correspondence with the weight of the ink cartridge and the ink liquid inside thereof. However, there is a problem that an extra resistance force is applied to the drive source of the carriage, and when the ink cartridge is downsized, the ink cartridge is frequently replaced due to the consumption of ink, and a large amount of continuous recording can be performed quickly. There was an inconvenience that I could not.

Therefore, as disclosed in JP-A-5-16382, a replaceable ink supply source such as an ink cartridge is arranged on the recording apparatus main body side, and a flexible tube is connected from the ink supply source. A configuration is known in which ink is supplied to a print head on a carriage via the ink.

As disclosed in this publication, the sub-tank which is detachably connected to the print head is mounted on the carriage together with the print head and integrally scans and moves. Instead of completely filling the ink, it is used in the state where a predetermined amount of air is stored. Due to the presence of this air portion, the impact force caused by the movement / stop of the print head is mitigated, and the ink prevents pressure fluctuations in the ejection channel of the print head
It was intended to maintain uniform injection performance.

[0005]

However, when the print head is started and stopped frequently and rapidly in response to the recent demand for higher printing speed, the air reservoir portion of the sub-tank is hermetically sealed. In addition, due to the inertial flow of ink in the flexible tube from the ink supply source to the sub tank of the print head, the pressure fluctuation in the sub tank becomes too large. As a result, when the pressure in the sub-tank is too large on the positive pressure side, the withstand pressure of the meniscus at the nozzle portion is exceeded, ink leaks from the nozzle surface and carelessly stains the recording medium, or the printing performance deteriorates. On the contrary, if the pressure in the sub tank is too large on the negative pressure side, the ink meniscus at the nozzle will be broken, and during printing, the atmosphere will enter from the nozzle into the print head and collect as air bubbles in the ejection channel. However, there has been a problem that the problem of causing ejection failure frequently occurs.

The present invention has been made to solve such a problem, and a dynamic pressure absorption tank is connected to an air portion of a buffer tank connected to a print head that moves and stops integrally with a carriage. A filter is provided to support the ink filled in the dynamic pressure absorption tank, and the meniscus formed in the filter is breached according to the fluctuation of the back pressure in the buffer tank to release air or supply ink. Accordingly, by providing a pressure fluctuation absorbing means configured to maintain the pressure balance, it is possible to provide an ink jet recording apparatus which eliminates ink leakage of the print head, suction of bubbles, etc., and prevents printing defects. Is a technical issue.

[0007]

In order to achieve this technical object, an ink jet recording apparatus according to a first aspect of the present invention is an atmosphere open type ink tank for accumulating ink, a plurality of ejection channels and communicating with them. In the ink jet recording apparatus, a print head having a nozzle for ejecting ink droplets to the atmosphere and an ink supply path for supplying ink from the ink tank to a buffer tank connected to the print head are provided. Arranging a dynamic pressure absorption tank that communicates with the air part in the tank, partition the upper part of the dynamic pressure absorption tank with a filter, and make the buffer tank side of the filter communicate with the air part in the buffer tank, Ink is stored on the side of the filter opposite to the buffer tank, and the ink is Those configured to form a small breakdown voltage meniscus filters than meniscus pressure resistance in the nozzle of the shaped head.

An ink jet recording apparatus according to a second aspect of the present invention is a printer having an ink tank that is open to the atmosphere for storing ink, a plurality of ejection channels, and nozzles that communicate with the ejection channels and eject ink droplets to the atmosphere. Head and
In an ink jet recording apparatus including a buffer tank connected to the print head and an ink supply path for supplying ink from the ink tank, a dynamic pressure absorbing tank communicating with an air portion in the buffer tank, and the dynamic pressure absorbing tank. The upper part of the tank is partitioned by a filter, the buffer tank side of the filter is defined as a space communicating with the air portion of the buffer tank, and ink is stored on the side opposite to the buffer tank of the filter, When the back pressure is high, the air in the buffer tank is allowed to pass through the filter to the ink side in the dynamic pressure absorption tank, and when the back pressure is low, the ink in the dynamic pressure absorption tank passes through the filter. It is configured to allow passage in the buffer tank direction.

According to a third aspect of the present invention, in the ink jet recording apparatus according to the first or second aspect, the height position of the ink tank with respect to the print head is changed from the nozzle of the print head to the ink. The back pressure is set so that a back pressure is applied to the buffer tank so that the drops do not leak.

The invention according to claim 4 is the same as claim 1
The ink jet recording apparatus according to any one of claims 1 to 3, wherein the dynamic pressure absorbing tank is configured such that the ink storage side can be opened to the atmosphere at least during printing operation.

Further, according to a fifth aspect of the invention, in the ink jet recording apparatus according to any one of the first to fourth aspects, ink is replenished from the ink tank to the dynamic pressure absorbing tank by an ink replenishing pump. It is configured to do.

According to a sixth aspect of the invention, in the ink jet recording apparatus according to any one of the first to fifth aspects, the ink tank temporarily stores ink supplied from an ink supply source such as an ink cartridge. It is a sub tank.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic sectional view of an ink jet recording apparatus of the present invention, FIG. 2 is a sectional view of an essential part of a second embodiment, and FIG. 3 is a sectional view of an essential part of a third embodiment. A print head 2 having a plurality of ejection channels (not shown) is arranged on the lower side of the head unit 1, and a manifold chamber 3a communicating with all the ejection channels is provided on the upper side.
A manifold body 3 having the above is arranged, and both are bonded and fixed to form a unit.

The head unit 1 is fixedly mounted on the lower surface side of the carriage 4 with an adhesive agent or the like, and the buffer tank 5 is removably fixed to the upper surface side thereof with mounting screws 6. The other end of a flexible tube 31 made of synthetic resin, one end of which is connected to an ink cartridge 30 serving as an ink tank which is an ink supply source, is connected to a connecting member 14 fixedly provided on the side of the carriage 4, The other end of the flexible tube 13 made of synthetic resin for relay connected to the connection member 14 is connected to the ink inlet 8 of the buffer tank 5. In that case, the ink in the ink cartridge 30 may be replenished and supplied to the buffer tank 5 by driving the pump 33 for supplying ink.
The suction purging device, which will be described later, may be used to supply ink by the siphon principle.

The ink in the ink cartridge 30 may be supplied to a sub tank (not shown), and the sub tank may supply the ink to the buffer tank 5 via a pump. In these cases, the ink cartridge 30 and the sub-tank are provided with an atmosphere opening portion.

In this embodiment, the ink cartridge 30 is arranged outside the carriage at a predetermined position on the main body side of the recording apparatus, and the carriage 4 is mounted via a timing belt, a step motor or the like (not shown). It is configured to be capable of reciprocating in a direction orthogonal to the paper surface of FIG. The carriage 4 reciprocates along the surface of a sheet (not shown) as a recording medium and along a carriage movement direction orthogonal to the sheet feeding direction. One end of the carriage 4 in the movement direction is moved. Is provided with a suction cap 37 for suction purging so as to face the print head 2. The suction cap 37 serves as a nozzle on the front surface (lower surface) of the print head 2 during suction purging and ink cartridge replacement. The drain tank 40 is closely contacted so as to cover the portion, and the drain tank 40 is attached via the suction pipe 38 and the suction pump 39.
Is discharged to.

Next, the print head 2 will be described.
Although it is not shown because it has a known structure as disclosed in Japanese Patent Laid-Open No. 2000-103084 and the like, it has a structure in which two actuator substrates each having a plurality of ejection channels on both sides of the substrate are adhered to each other, and the lower surface thereof is Nozzles communicating with each injection channel are opened in two rows.
On the upper surface of each actuator substrate, a manifold body 3 is provided in which a manifold chamber 3a is arranged so as to communicate with each of the injection channels. The introduction pipes 12 and 12 connected to the upper surfaces of the manifold chambers 3a and 3a (only one of which is shown in FIG. 1) are connected to ink outlets 10 opened in a bottom plate 5a of a buffer tank 5 which will be described later via seal pipes 18 and 18. It is connected. As a configuration for ejecting the ink in each ejection channel, it is preferable that the side wall of the actuator substrate near the ejection channel is made of a piezoelectric material and the ink is ejected by the deformation of the piezoelectric material.

An ink inflow cylinder 8 hangs down from the ceiling wall 7 of the buffer tank 5 and opens near the bottom plate 5a of the buffer tank 5. The upper end of the ink inflow cylinder 8 projects upward from the ceiling wall 7. Further, an opening 9 for connecting a dynamic pressure absorbing tank 20 as a pressure fluctuation absorbing means is formed in a portion of the ceiling wall 7 close to one side,
As can be understood from FIG. 1, the inner surface (ceiling surface) 7a of the ceiling wall 7 is an inclined surface having an appropriate inclination angle θ with respect to the horizontal plane so that it is low on the one hand as a whole and is high on the opening 9 side. Is formed in. This tilt angle θ is approximately 5 degrees as an allowable tilt angle (device allowable tilt angle) when a main body (not shown) of a printer equipped with the ink jet recording apparatus of the present embodiment is placed on a mounting surface such as a table. The added value is about 5 to 15 degrees in the embodiment, and more preferably about 10 degrees.

Each of the pair of ink outlets 10 and 10 projecting downward from the bottom plate 5a of the buffer tank 5 has an upper surface side (inside the buffer tank 5) of 5 μm or more.
A filter 11 having a mesh size of about 10 μm is stretched so that bubbles and foreign matters in the ink can be captured.

The liquid level of the ink in the ink cartridge 30 that is open to the atmosphere is appropriately higher than the height position of the nozzle surface of the print head 2 (the lower surface of the print head) by H2.
(In the embodiment, the water column (head of water) is set to 100 mm) so that the ink pressure on the nozzle surface of the print head 2 is set to a negative pressure (100 mm lower than the water column (head of head)) as compared with the atmosphere.

In the opening cylinder 9 communicating with the upper side near the air portion (ceiling wall 7) in the buffer tank 5, a pressure fluctuation absorbing means is provided via a connecting pipe 21 made of a flexible tube made of synthetic resin or the like. The replaceable is a dynamic pressure absorption tank 20 whose upper part is formed in a funnel shape. The upper portion (large diameter portion) of the dynamic pressure absorption tank 20 has a thickness of 15 μm to 50 μm.
The upper and lower sides are partitioned by a filter 22 having a mesh size of about m, and the damper ink 24 is supported on the filter 22. The destructive pressure of the ink meniscus formed on the filter 22 (hereinafter referred to as the meniscus withstand pressure) P3 is
P1 of the meniscus pressure resistance of the nozzle portion of the print head 2
It is set to be smaller than. A back pressure is applied to the ink in the buffer tank 5 due to the pressure difference P2 between the liquid surface of the ink in the ink cartridge 30 and the nozzle surface, and the back pressure is smaller than the meniscus pressure resistance P1 of the nozzle portion. By setting, in a normal stationary state, the ink meniscus in the nozzle portion is not destroyed, the ink does not carelessly leak from the nozzle surface, and the meniscus of the damper ink 24 in the location of the filter 22 is not destroyed. The damper ink 24 is supported by the filter 22 above the dynamic pressure absorption tank 20 and does not leak downward.

Further, as a first embodiment, as shown in FIG. 1, the dynamic pressure absorption tank 20 is hermetically sealed, and an opening / closing valve 23 which is controlled to be opened / closed by a sensor and an actuator (not shown) is connected to the upper wall. At the time of the suction purging, the sensor detects the movement of the carriage to the suction work position and closes the opening / closing valve 23 so that the damper stored above the dynamic pressure absorbing tank 20 (the filter 22). The ink 24 is suppressed so as not to fall (is not drawn) into the buffer tank 5 via the filter 22. During the printing operation, since the position of the carriage 4 deviates from the suction purge position, the sensor detects this and opens the opening / closing valve 23.

Then, in accordance with the pressure fluctuation in the buffer tank 5, the bubbles and the damper ink 24 are exchanged in the dynamic pressure absorbing tank 20 as described below, whereby the back pressure on the nozzle surface of the print head 2 is changed. Can be held substantially constant.

That is, when the ink in the tubes 13 and 31, which are the ink supply paths, moves forward toward the inlet cylinder 8 of the buffer tank 5 due to the movement of the carriage 4, the pressure in the buffer tank 5 increases. Then, from the meniscus breakdown voltage P3 in the filter 22, the buffer tank 5
When the internal pressure becomes large, the air in the air portion in the buffer tank 5 destroys the ink meniscus in the filter 22 and becomes air bubbles that pass through the damper ink 24 on the upper side of the dynamic pressure absorption tank 20 to the atmosphere. Open to the public.

On the other hand, the tube 1 which is the ink supply path
When the ink in the ink tanks 3 and 31 retreats away from the inlet cylinder 8 of the buffer tank 5,
The pressure inside is reduced. When the pressure becomes smaller than the meniscus withstand voltage of the filter 22, the meniscus of the filter 22 is destroyed, and the damper ink 24 supported by the filter 22 drops little by little into the buffer tank 5, thereby reducing the pressure drop. To compensate.
When the pressure in the buffer tank 5 becomes substantially equal to the meniscus pressure resistance in the filter 22, the damper ink 24
Is stopped from falling into the buffer tank 5.

When the damper ink 24 in the dynamic pressure absorbing tank 20 in the first embodiment shown in FIG. 1 is consumed, the dynamic pressure absorbing action (damper action) is lost, so that the damper ink 24 is full. The new dynamic pressure absorption tank 20 is replaced.

In the second embodiment shown in FIG. 2, the dynamic pressure absorbing tank 20 is supplied from the ink cartridge 30 or the like as the ink tank through the replenishing pipe 26 and the replenishing pump 27.
The damper ink 24 can be replenished (supplemented) to the upper side of the. In this embodiment, the liquid level of the damper ink 24 on the upper side of the dynamic pressure absorbing tank 20 is constantly monitored by a sensor (not shown), and when the liquid level falls below a certain level, the replenishment pump 27 is driven. It is sufficient to replenish the damper ink 24. Since the other constituent elements in the second embodiment are the same as those in the first embodiment, the same components and parts are designated by the same reference numerals, and detailed description thereof will be omitted.

As described above, by moving the carriage 4 (print head 2), the tubes 13 and 31 for supplying ink from the ink tank such as the ink cartridge 30 at the fixed position to the buffer tank 5 that moves. Even if the ink moves forward and backward due to inertial force and the back pressure in the buffer tank 5 fluctuates oscillatingly, the filter 2 in the dynamic pressure absorbing tank 20 communicating with the air portion of the buffer tank 5
Damper ink 24 and filter 2 supported on
By utilizing the meniscus pressure resistance by 2 and 2, the air bubbles in the buffer tank 5 are allowed to escape to the dynamic pressure absorption tank 20, and conversely, the damper ink 24 is replenished to the buffer tank 5 to operate, and As a result of being able to maintain the back pressure substantially constant, even if the back pressure in the buffer tank 5 varies over a wide range from high frequency to low frequency, ink leaks from the print head 2 and air bubbles are sucked from the nozzles. Can be eliminated.

An ink supply path 133 from the ink tank such as the ink cartridge 30 to the buffer tank 5 is provided.
Even if the supply pump 33 is not provided in the first unit, the ink supply due to the ink consumption can be automatically performed by the siphon principle. Further, the print head 2 has, instead of the above-described configuration, a unit for locally boiling and ejecting ink by a known heat generating unit, and an electro-mechanical displacement converting unit such as a piezoelectric element for a plane-sided ejection channel. Those facing each other can be applied. Also in these cases, the ink outlet of the buffer tank is connected to the manifold chamber that distributes the ink to the plurality of ejection channels.

[0030]

As described above, claim 1
The ink jet recording apparatus according to the invention described in 1), a print head having an open-air type ink tank for storing ink, a plurality of ejection channels and nozzles communicating with the ejection channels for ejecting ink droplets to the atmosphere, and the print head. In an ink jet recording apparatus having a buffer tank connected to an ink supply path for supplying ink from the ink tank, a dynamic pressure absorption tank communicating with an air portion in the buffer tank is arranged, and the dynamic pressure absorption tank is provided. The inner upper part is partitioned by a filter, the buffer tank side of the filter is defined as a space communicating with the air part in the buffer tank, and ink is stored on the side opposite to the buffer tank of the filter, and the ink is the filter. At a pressure resistance lower than the meniscus pressure resistance at the nozzle of the print head. Since it is configured to form a filter, the ink in the ink supply path from the ink tank to the buffer tank moves forward and backward due to inertial force along with the movement of the print head and the buffer tank. When the back pressure increases or decreases below a specified value and the balance between the meniscus pressure resistance and the back pressure in the filter supporting the ink in the upper portion of the dynamic pressure absorption tank is broken, the air in the buffer tank is supported by the filter. The back pressure in the buffer tank can be maintained at a substantially constant level by releasing air as bubbles in the damper ink to the atmosphere, or by replenishing the damper ink in the buffer tank, and the ink leaks from the print head. In addition, it is possible to eliminate inconveniences such as nozzle clogging by sucking bubbles from the nozzle. Unlikely to.

An ink jet recording apparatus according to a second aspect of the present invention is a printer having an ink tank that is open to the atmosphere for storing ink, a plurality of ejection channels and nozzles that communicate with the ejection channels and eject ink droplets to the atmosphere. Head and
In an ink jet recording apparatus including a buffer tank connected to the print head and an ink supply path for supplying ink from the ink tank, a dynamic pressure absorbing tank communicating with an air portion in the buffer tank, and the dynamic pressure absorbing tank. The upper part of the tank is partitioned by a filter, the buffer tank side of the filter is defined as a space communicating with the air portion of the buffer tank, and ink is stored on the side opposite to the buffer tank of the filter, When the back pressure is high, the air in the buffer tank is allowed to pass through the filter to the ink side in the dynamic pressure absorption tank, and when the back pressure is low, the ink in the dynamic pressure absorption tank passes through the filter. It is configured to allow passage in the direction of the buffer tank. With this configuration, the print head The back pressure in the buffer tank may increase or decrease below the set value as the ink in the ink supply path from the ink tank to the buffer tank moves forward and backward due to inertial force as the buffer tank moves. If the back pressure in the buffer tank is higher than the set value by partitioning the damper ink in the upper part of the dynamic pressure absorption tank and the air part of the buffer tank with the filter having the above-mentioned configuration arranged in the dynamic pressure absorption tank. The air in the buffer tank is opened to the atmosphere as bubbles on the damper ink side. On the contrary, when the back pressure in the buffer tank is lower than the set value, the damper ink passes through the filter and enters the buffer tank to reduce the volume of the air portion in the buffer tank to reduce the back pressure. Since the back pressure in the buffer tank can be reliably absorbed by increasing the back pressure, the back pressure in the buffer tank can be maintained at a substantially constant level. Even if it fluctuates, there is an effect that ink is not leaked from the print head, and bubbles are not sucked into the ejection channel from the nozzle to cause nozzle clogging.

According to a third aspect of the present invention, in the ink jet recording apparatus according to the first or second aspect, the height position of the ink tank with respect to the print head is changed from the nozzle in the print head to the ink. Since the back pressure is set so that a drop pressure does not leak to the buffer tank, in addition to the effect of the invention according to claim 1 or 2, the location where the ink tank is arranged is as described above. You can easily prevent ink from leaking from the nozzles of the print head just by setting it.

The invention described in claim 4 is the same as claim 1
The ink jet recording apparatus according to any one of claims 1 to 3, wherein the dynamic pressure absorbing tank is configured such that the ink storage side can be opened to the atmosphere at least during printing operation. Fluctuations in the back pressure in the buffer tank due to causes other than consumption can be absorbed by a simple structure of the damper ink and the filter arranged in the dynamic pressure absorbing tank.

Further, the invention according to claim 5 is the ink jet recording apparatus according to any one of claims 1 to 4, wherein ink is replenished from the ink tank to the dynamic pressure absorbing tank by an ink replenishing pump. Since it is configured to do so, there is an effect that the ink in the upper part in the dynamic pressure absorbing tank is not exhausted and the dynamic pressure absorbing action can be ensured.

According to a sixth aspect of the present invention, in the ink jet recording apparatus according to any of the first to fifth aspects, the ink tank temporarily stores ink supplied from an ink supply source such as an ink cartridge. Since it is a sub-tank,
Even when the ink cartridge is replaced, since a predetermined amount of ink is stored in the sub tank, the back pressure applied to the buffer tank can be made substantially constant, and the ink does not accidentally leak from the nozzle of the print head. Produce an effect.

[Brief description of drawings]

FIG. 1 is a diagram of an inkjet recording apparatus according to a first embodiment of the present invention.

FIG. 2 is a diagram of an inkjet recording apparatus according to a second embodiment.

[Explanation of symbols]

2 print head 4 carriage 5 buffer tank 5a bottom plate 7 ceiling wall 8 ink inflow cylinder 9 opening cylinder 13 flexible tube 14 connecting member 20 dynamic pressure absorbing tank 22 as a part of pressure fluctuation absorbing means 22 part of pressure fluctuation absorbing means 23 as opening and closing valve 24 Ink for damper as a part of pressure fluctuation absorbing means 30 Ink cartridge 31 Flexible tube 33 Pump

Claims (6)

[Claims] 1. An ink tank that is open to the atmosphere for storing ink, a print head having a plurality of ejection channels and nozzles that communicate with the ejection channels and discharge ink droplets to the atmosphere, and a buffer tank connected to the print head. In the ink jet recording apparatus provided with an ink supply path for supplying ink from the ink tank, a dynamic pressure absorption tank communicating with the air part in the buffer tank is arranged, and an upper part of the dynamic pressure absorption tank is covered by a filter. The partition, the buffer tank side of the filter is a space communicating with the air portion in the buffer tank, ink is stored on the side of the filter opposite to the buffer tank, and the ink is the print head in the filter. To form a meniscus filter with a pressure resistance smaller than that of the nozzle Ink jet recording apparatus is characterized in that form. 2. An ink tank which is open to the atmosphere for storing ink, a print head having a plurality of ejection channels and nozzles communicating with the ejection channels for ejecting ink droplets to the atmosphere, and a buffer tank connected to the print head. In the ink jet recording apparatus having an ink supply path for supplying ink from the ink tank, a dynamic pressure absorption tank communicating with the air portion in the buffer tank, and an upper part of the dynamic pressure absorption tank is partitioned by a filter, The buffer tank side of the filter is a space communicating with the air portion in the buffer tank, ink is stored on the opposite side of the filter from the buffer tank, and when the back pressure in the buffer tank is high, the buffer is Allow the air in the tank to pass through the filter to the ink side in the dynamic pressure absorption tank, and When is low,
An ink jet recording apparatus, wherein ink in a dynamic pressure absorbing tank is allowed to pass through the filter toward a buffer tank. 3. A height position of the ink tank with respect to the print head is set so that a back pressure that prevents ink droplets from leaking from a nozzle of the print head is applied to the buffer tank. The inkjet recording device according to claim 1 or 2. 4. The ink jet recording apparatus according to claim 1, wherein the dynamic pressure absorbing tank is configured such that an ink storage side thereof can be opened to the atmosphere at least during a printing operation. . 5. The ink jet recording apparatus according to claim 1, wherein the dynamic pressure absorbing tank is configured to be replenished with ink from the ink tank by an ink replenishing pump. 6. The ink jet recording apparatus according to claim 1, wherein the ink tank is a sub tank that temporarily stores ink supplied from an ink supply source such as an ink cartridge.