JP2001212972A - Ink-jet type recording apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve a throughput in an ink-jet type recording apparatus in which ink is supplemented under reduced pressure. SOLUTION: In this ink-jet type recording apparatus, ink is supplemented through an ink-supplementing tube 8 from a main tank 21 constituting an ink cartridge to a sub tank 7 loaded on a carriage, and ink drops are discharged by a recording head 6 based on printing data to execute printing. A decompression chamber 22 and an ink storage chamber 23 are formed to the sub tank 7. The ink is supplemented from the main tank by pressure reduction of the decompression chamber. The ink is supplied to the ink storage chamber 23 via a one-way valve 35 from the decompression chamber 22. In this constitution, the ink can be supplemented from the main tank to the decompression chamber while the printing operation by a recording head is continued in receipt of the ink supply from the ink storage chamber.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sub-tank for supplying ink to a recording head mounted on a carriage on which a recording head is mounted. The sub-tank is supplied from a main tank via an ink supply tube to the sub-tank. The present invention relates to an ink jet recording apparatus configured to supply ink.

[0002]

2. Description of the Related Art Ink jet recording apparatuses have been used in many printings including color printing in recent years, since noise during printing is relatively small and small dots can be formed at a high density. Such an ink jet recording apparatus is generally provided with an ink jet recording head mounted on a carriage and moving in the width direction of the recording paper, and paper feeding means for moving the recording paper in a direction perpendicular to the moving direction of the recording head. Then, printing is performed on the recording paper by ejecting ink droplets from the recording head based on the print data.

[0003] On the carriage, for example, black,
Equipped with a recording head capable of discharging yellow, cyan, and magenta inks, full-color printing is enabled by changing the discharge ratio of each ink as well as text printing using black ink.

On the other hand, in this type of recording apparatus provided for office use or business use, it is necessary to provide a large-capacity ink cartridge in order to cope with a relatively large amount of printing. 2. Description of the Related Art There has been provided a recording apparatus of a type in which a main tank as a cartridge is loaded into a mounting apparatus (cartridge holder) arranged, for example, on a side of an apparatus main body.

A sub-tank is arranged on a carriage on which the recording head is mounted. Ink is supplied from each of the main tanks to each of the sub-tanks via an ink supply tube. It is configured to supply ink thereto.

[0006]

By the way, recently, it is possible to perform printing on a larger sheet of paper.
There is a demand for a large-sized printing apparatus having a long scanning distance of the carriage. In such a printing apparatus, in order to improve the throughput, the number of nozzles in the printing head is increased more and more. Furthermore, in order to improve throughput, it is possible to replenish ink from the main tank to each sub-tank mounted on the carriage sequentially while performing printing, and to stabilize ink from each sub-tank to the print head. There is a demand for a recording device that supplies the data.

In such a recording apparatus, it is necessary to connect an ink supply tube corresponding to each ink from the main tank to the sub-tank, and since the scanning distance of the carriage is large, the tube is inevitably routed. The distance increases. Moreover, as described above, since the number of nozzles in the recording head is increased, the ink consumption is large, the dynamic pressure of the ink increases in each ink supply tube connected from the main tank to the sub tank, and the There is a technical problem that the ink supply amount is insufficient.

As one means for solving such a problem, for example, the pressure in the sub-tank is reduced to a negative pressure, an ink flow is generated from the main tank to the sub-tank by the negative pressure, and the sub-tank is necessary and sufficient. A configuration for replenishing a suitable ink is conceivable.

Although many patent applications have been filed for replenishing the ink in the sub-tank by reducing the pressure, in any case where the sub-tank is replenished with ink, a negative pressure is applied to the sub-tank. Because it is necessary to reduce the pressure in this depressurized state,
It becomes difficult to supply ink to the recording head.

For this reason, in a state where ink is supplied to the sub-tank, the printing operation must be temporarily stopped, which causes a problem that the throughput is reduced.

SUMMARY OF THE INVENTION The present invention has been made to solve such a technical problem, and an object of the present invention is to use a recording head even in a case where the sub-tank is supplied with reduced pressure as described above. An object of the present invention is to provide an ink jet recording apparatus capable of continuously executing a printing operation.

[0012]

In order to achieve the above-mentioned object, an ink jet recording apparatus according to the present invention comprises a recording head mounted on a carriage and reciprocated in the width direction of recording paper; An ink jet recording apparatus, comprising: a sub-tank mounted on a carriage together with a head, receiving ink supply from a main tank via an ink supply path, and supplying ink to the recording head. Is formed, the ink is supplied from the main tank to the decompression chamber by the decompression of the decompression chamber, and the ink supplied to the decompression chamber is supplied to the ink storage chamber formed in the sub tank via a one-way valve. The ink is supplied from the ink storage chamber to the recording head.

In this case, a flexible ink supply tube is preferably used as an ink supply path from the main tank to the sub tank.

In the decompression chamber formed in the sub-tank, there is disposed a decompression state or a decompression control means for stopping the decompression state in accordance with the storage amount of ink supplied from the main tank. In this case, the ink is introduced from the main tank into the decompression chamber.

In this case, preferably, the decompression control means disposed in the decompression chamber of the sub-tank includes a float member which floats by the ink stored in the decompression chamber, and an air valve which is opened / closed according to the floating position of the float member. The air valve is connected to a negative pressure generating means.

A plurality of sub-tanks for individually handling each ink are mounted on the carriage, and each air valve provided in a decompression chamber of each sub-tank is connected to one negative pressure generating means. It is desirable to have been.

Further, preferably, the air valve is:
A valve member made of a soft material having a valve opening communicating with the negative pressure generating means, and a seal member disposed on the float member and closing the valve opening of the valve member with movement of the float member. You.

On the other hand, it is preferable that the lower bottom of the ink storage chamber is formed at a position lower in the direction of gravity than the lower bottom of the decompression chamber in the sub tank. Preferably, the one-way valve for supplying the ink supplied to the decompression chamber to the ink storage chamber is arranged at a lower bottom portion of the decompression chamber or in the vicinity thereof. In addition, preferably, an ink supply port for supplying ink to the recording head is formed at a lower bottom portion of the ink storage chamber in the sub tank or in the vicinity thereof.

The pressure reducing chamber is provided with a pressure reducing opening communicating with a pressure reducing valve. In this case, in a preferred embodiment, the pressure reducing release valve is disposed on a carriage. Further, a configuration in which the decompression release valve is arranged on the recording apparatus main body side via a flexible decompression release tube can also be suitably adopted.

According to the ink jet recording apparatus constructed as described above, when the ink in the decompression chamber constituting the sub-tank becomes equal to or less than a predetermined value, the position of the float member in the sub-tank constituting the decompression control means is lowered. Then, the air valve communicating with the pressure reducing pump as the negative pressure generating means is opened. As a result, the decompression chamber is brought into a decompressed state by the action of the decompression pump. Therefore, the ink is supplied to the decompression chamber more quickly than the main tank by the action of the negative pressure.

When ink is replenished to a predetermined liquid level in the decompression chamber of each sub-tank, the air valve disposed on each of the sub-tanks is closed by floating of the float member, and the decompression state is released. Thus, the supply of the ink in each of the decompression chambers is stopped in an appropriate filling state.

In this case, as described above, the pressure reduction control means is configured to communicate with one negative pressure generation means via each air valve provided in the pressure reduction chamber for storing each ink, Therefore, ink can be filled while applying a common negative pressure to the decompression chamber of each sub tank. Then, the air valves are sequentially closed according to the amount of ink stored in the decompression chamber in each sub-tank, and the supply of ink to each of the sub-tanks is completed.

On the other hand, the ink supplied to the decompression chamber of each sub-tank is supplied to the ink storage chamber formed in the sub-tank via a one-way valve according to the gravity of the ink, and the ink in the decompression chamber is supplied to the ink storage chamber. Is replenished to be almost the same as the storage line. Then, the ink stored in the ink storage chamber is supplied to the recording head, and ink droplets are ejected according to the print data applied to the recording head, and printing on the recording paper is performed.

When the amount of ink in the decompression chamber becomes equal to or less than a predetermined value due to the execution of printing or the like, the above-described decompression replenishment is performed again. In this case, since the ink storage chamber is separated from the decompression chamber by the one-way valve, the ink supply from the ink storage chamber to the recording head is continued even during the ink supply operation from each main tank. can do.

[0025]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an ink jet recording apparatus according to the present invention will be described based on an embodiment shown in the drawings. FIG. 1 is a top view showing an example of an ink jet recording apparatus to which the present invention can be applied. In FIG. 1, reference numeral 1 denotes a carriage. The carriage 1 is guided by a guide member 4 via a timing belt 3 driven by a carriage motor 2 so as to be reciprocated along the longitudinal direction of the paper feed member 5. It is configured. An ink jet recording head 6 is mounted on a surface of the carriage 1 facing the recording paper.

A sub-tank 7 for supplying ink to the recording head 6 is provided above the carriage 1.
Is installed. In this embodiment, four sub-tanks 7 are provided corresponding to the respective inks in order to temporarily store the respective inks therein. Each of the sub-tanks 7 is provided with four ink supply tubes 8, 8,... Constituting an ink supply path from a main tank as an ink cartridge, which will be described later, disposed on the main body side of the apparatus.
It is configured to supply yellow, magenta, and cyan inks.

On the other hand, from each of the sub-tanks 7, one common pressure-reducing tube 9 connected to a pressure-reducing pump as negative pressure generating means to be described later for bringing the inside of each sub-tank 7 into a reduced pressure state is led out. Further, the recording head 6
A capping device 10 that can seal the nozzle forming surface of the recording head 6 is disposed in a non-printing area on the moving path of the recording head 6. On the upper surface of the capping device 10, when the carriage 1 moves to the non-printing area, that is, the right end in the drawing, the carriage 1 moves upward following the movement of the carriage 1 to seal the nozzle forming surface of the recording head 6. A cap member 10a for stopping is provided.

The capping device 10 functions as a lid that seals the nozzle forming surface of the recording head 6 to prevent drying of the nozzle openings during the idle period of the recording device. It functions as an ink receiver at the time of a flushing operation in which no drive signal is applied and ink droplets are ejected idly, and further performs a cleaning operation of suctioning and discharging ink from the recording head by applying a negative pressure by a suction pump to be described later to the recording head. It also has a function to execute.

Although not shown in FIG. 1, one end of a tube of a suction pump (tube pump) is connected to the cap member 10a, and the other end of the tube via the suction pump is described later. It is connected to a waste liquid tank 11 containing a waste liquid absorbing material to be discharged, whereby the waste liquid discharged by the above-described cleaning and flushing operation is sent to the tank 11.

FIG. 2 schematically shows the structure of one ink supply system provided in the recording apparatus shown in FIG. 1. In FIG. 2, the same parts as those in FIG. 1 are denoted by the same reference numerals. Reference numeral 21 in FIG. 2 indicates a main tank as an ink cartridge.
1 is loaded in a cartridge holder (not shown) arranged on the main body side of the apparatus.

The main tank 21 includes, for example, a closed ink bag (ink pack) formed of a flexible material in which ink is sealed inside, and an external box formed of, for example, a synthetic resin and formed into a box shape. And a case.

The ink is supplied from the ink pack in the main tank 21 to the sub-tank 7 loaded on the carriage 1 via the ink supply tube 8 as an ink supply path.
In FIG. 2, the main tank 21, the ink supply tube 8 and the sub-tank 7 are each represented one by one, but in the present embodiment, black, yellow, cyan and magenta inks are respectively used. There are four sets of configurations to handle.

FIGS. 3 to 5 show the detailed structure of the sub-tank 7 in a sectional view. FIG. 3 shows a state in which the amount of stored ink in the sub-tank 7 is reduced. 5 shows a state in which the ink is replenished, and FIG. 5 shows a state in which the pressure reducing release valve is opened immediately after the ink is replenished to the sub tank 7 as described later.

The sub-tank 7 includes a decompression chamber 22 and an ink storage chamber 23. The ink supplied from the main tank 21 via the ink supply tube 8 is supplied to the decompression chamber 22 in the vicinity of the lower bottom portion 22a of the decompression chamber 22 via an ink supply tube 24 formed vertically inside the decompression chamber 22. It is configured so that ink can be supplied to the inside.

The decompression chamber 22 is provided inside the decompression chamber 22.
The float member 25 which floats by the ink stored in 2 is arrange | positioned. The float member 25 is configured to be movable up and down in the direction of gravity with a support shaft 26 disposed in the decompression chamber 22 in a horizontal direction as a rotation center.

A seal member 27 is attached to the upper part of the float member 25.
Is a valve member 2 formed of a soft member such as rubber, which floats with the ink replenished into the decompression chamber 22 and forms an air valve disposed above the decompression chamber 22.
8.

As shown in FIG. 3, the valve member 28 is formed with a valve opening 28a penetrating the central portion thereof. Therefore, the floating of the float member 25 causes the seal member 27 to close the valve opening 28a. By doing so, the air valve is closed, whereby the suction port 29 leading to a pressure reducing pump as a negative pressure generating means to be described later is closed. That is, the float member 2
5, and an air valve comprising a seal member 27 and a valve member 28 constitute a pressure reduction control means.

On the other hand, one end of the decompression tube 9 is connected to the suction port 29 as shown in FIGS. 1 and 2, and the other end is connected to a decompression pump 31 arranged on the main body side of the recording apparatus. ing. Although not shown in the drawing, the end of the suction port 29 in each sub tank 7 is communicated transversely, and this communication portion is connected to the decompression tube 9, and is connected via one decompression tube 9. Connected to one pressure reducing pump 31.

With this configuration, each sub tank 7
One decompression pump 31 for each decompression chamber 22 in
Negative pressure is applied to each sub-tank 7 as described later.
, So that ink can be supplied from the main tank.

The decompression chamber 2 in the sub-tank 7
2, a decompression release port 32 is formed, and this decompression release port 32 is connected to a decompression release valve 34 mounted on the carriage 1 via a decompression release tube 33 as shown in FIG. I have.

On the other hand, a one-way valve 35 is provided between the decompression chamber 22 and the ink storage chamber 23 so that ink can flow only from the decompression chamber 22 to the ink storage chamber 23 side. This one-way valve 35 is desirably arranged at or near the lower bottom of the decompression chamber. In the embodiment shown in the drawing, the one-way valve 35 is located at the center of the decompression chamber 22 and the ink storage chamber 23. It is arranged at the lower end of the partition wall 7a.

The decompression chamber 22 in the sub-tank
Lower bottom portion 23 of ink storage chamber 23 than lower bottom portion 22a.
It is desirable that a be formed at a lower position in the direction of gravity.

With such a configuration, the ink storage chamber 2
When the ink stored in 3 is consumed by the printing operation of the recording head 6 or the like, most of the ink stored in the decompression chamber 22 is supplied to the ink storage chamber 23 side via the one-way valve 35 by its own weight. be able to.

In the ink storage chamber 23, the recording head 6 is provided.
Is formed with an ink supply port 23b for supplying ink to the printer. In this case, the ink supply port 23b is desirably formed at the lower bottom of the ink storage chamber or in the vicinity thereof,
In this embodiment, the ink supply port 23b is formed at the lower end of the side wall of the ink storage chamber 23.
The tube 37 connected to the ink supply port 23b
Is configured to supply ink to the recording head 6 via the.

With this configuration, until the liquid level of the ink stored in the ink storage chamber 23 reaches the vicinity of the lower bottom thereof,
The supply of ink to the sub tank can be stopped,
It is possible to substantially widen the operation interval of the reduced pressure supply described later.

An air opening 36 is formed in the upper part of the ink storage chamber 23.
When the ink is supplied from the decompression chamber 22 to the ink storage chamber 23 via the one-way valve 35, or when the ink in the ink storage chamber 23 is consumed by the recording head 6, the ink is supplied to the ink storage chamber 23. The air acts to introduce and discharge air.

As shown in FIG. 2, the discharge side of the suction pump 38 connected to the capping device 10 for sealing the nozzle forming surface of the recording head 6 is connected to the waste liquid tank 11. The waste liquid discharged by the above-described head cleaning operation or the like is configured to be held in a state of being absorbed by the waste liquid absorbing material 11a stored in the waste liquid tank 11.

In the above configuration, as shown in FIG. 3, when the amount of ink stored in the sub-tank 7 is reduced and ink is supplied to the sub-tank 7, the pressure reducing release valve 34 is closed. This drives the pressure reducing pump 31. Thereby, the negative pressure from the pressure reducing pump 31 is applied to the pressure reducing chamber 22 in the sub tank 7. In this case, the one-way valve 35 is closed, so that the decompression chamber 22 in each sub tank 7 is in a negative pressure state, and ink is supplied from the main tank 21 to the decompression chamber 22.

As the ink is supplied from the main tank 21, the float member 25 in the decompression chamber 22
Floats around the support shaft 26 as a rotation center, as shown in FIGS. Then, as shown in FIG. 4, when the ink amount in the decompression chamber 22 is almost full,
The float member 25 is in the most floating state, and the seal member 27 attached to the float member 25 closes the valve opening 28a of the valve member 28. As a result, the seal member 27 is closed while being attracted to the valve member 28 by receiving the negative pressure from the pressure reducing pump 31.

Therefore, the decompression chamber 22 is provided with the decompression pump 31
, The application of the negative pressure is released, and the supply of ink is stopped in the state shown in FIG. And the pressure reducing pump 31
When the pressure reduction chambers in all the sub-tanks 7 are almost completely filled with ink, the driving of the pressure reduction chambers is stopped and the pressure reduction release valve 34 is opened.

The operation of stopping the operation of the pressure reducing pump 31 and the operation of opening the pressure reducing opening valve 34 may be performed after a lapse of a predetermined time from the start of the operation of the pressure reducing pump 31. Further, when the load of the pressure reducing pump 31 increases, it is estimated that the ink is almost completely replenished in all the sub tanks in this state, and the pressure reducing pump 31
May be performed, and the pressure reducing release valve 34 may be opened.

By the above operation, as shown in FIG. 4, ink is supplied to the decompression chamber 22 of each sub tank 7 almost completely. By opening the decompression release valve 34, the ink in the decompression chamber 22 is supplied to the ink storage chamber 23 formed in the sub tank 7 via the one-way valve 35 based on the head difference of the ink. As shown in FIG. 5, ink is supplied to the ink storage chamber 23 so that the ink storage line in the pressure reduction chamber 22 becomes substantially the same as the ink storage line.

At this time, the float member 25 is slightly rotated in the direction of gravity as shown in FIG. 5 as the ink storage line in the decompression chamber 22 is lowered, and the valve is formed by the seal member 27 attached to the float member 25. Opening 28a
Is released.

Then, the ink stored in the ink storage chamber 23 is supplied to the recording head 6, and ink droplets are ejected based on the print data applied to the recording head, and printing on the recording paper is executed. When this printing is executed, the ink in the ink storage chamber 23 is consumed and the ink level is lowered, and the ink in the decompression chamber is sequentially supplied to the ink storage chamber 23 through the one-way valve 35.

Then, in a state where the ink storage amount in any one of the sub-tanks 7 becomes equal to or less than a predetermined value, the pressure-reducing release valve 34 is closed again, and the pressure-reducing pump 31 is driven to execute the above-mentioned pressure-reducing replenishment. During the execution of the decompression replenishment, the ink storage chamber 23 in the sub tank 7 is isolated from the negative pressure by the operation of the one-way valve 35, so that the printing is continued by the ink stored in the ink storage chamber 23. Can be done.

In the embodiment shown in FIG. 2, as described above, the pressure-reducing valve 34 is mounted on the carriage. In this case, the pressure reducing release valve 34
In order to perform the valve opening and valve closing operations described above, for example, an actuator such as an electromagnetic plunger is required, and the problem that the inertia of the carriage 1 is increased remains.

Therefore, a lever or the like protruding as necessary is arranged on the movement path of the carriage 1, and by moving the carriage 1 in one direction, the lever is engaged with the lever or the like to close the pressure reducing release valve 34 and By moving the carriage 1 in the other direction, the pressure reducing release valve 34 is engaged with the lever and the like.
It is also possible to adopt a mechanism that opens the valve.

FIG. 6 shows a structure in which an actuator such as an electromagnetic plunger or an opening / closing mechanism of a pressure reducing valve provided with a lever or the like can be controlled without mounting on a carriage in order to control the opening and closing of the pressure reducing valve 34. It is shown. In FIG. 6, parts corresponding to the parts already described are denoted by the same reference numerals, and therefore, detailed description thereof will be omitted.

That is, in the configuration shown in FIG. 6, the pressure reducing release valve 34 is disposed on the recording apparatus main body side, and the pressure reducing release port 32 in the sub tank on the carriage and the pressure reducing release valve 34 disposed on the recording apparatus main body side. Are connected by a decompression opening tube 33.

According to this configuration, the end of the decompression opening port 32 in each sub-tank is communicated transversely, and this communication part is connected via the decompression release tube 33 to one decompression release valve arranged on the recording apparatus main body side. 34 can be connected. Therefore, by adding one tube substantially between the recording apparatus main body side and the carriage side, an ink jet recording apparatus that performs the same function as the function shown in FIG. 2 can be configured.

As described at the beginning, the present invention can be suitably used particularly for a large-sized recording apparatus having a long scanning distance of a carriage. However, the present invention is applicable to other than such a specific recording apparatus. However, unique effects that do not lower the throughput can be obtained.

[0062]

As is apparent from the above description, according to the ink jet recording apparatus of the present invention, a sub-tank is provided with a decompression chamber and an ink storage chamber, and ink is supplied from the main tank by decompression of the decompression chamber. And the ink is supplied from the ink storage chamber to the ink storage chamber via the one-way valve. The ink can be supplied from the main tank to the decompression chamber while continuing. Therefore, in this type of ink jet recording apparatus that performs replenishment under reduced pressure, it is possible to greatly improve the throughput.

[Brief description of the drawings]

FIG. 1 is a top view showing an example of an ink jet recording apparatus to which the present invention can be applied.

FIG. 2 is a schematic diagram illustrating a configuration of an ink supply system provided in the recording apparatus illustrated in FIG. 1;

FIG. 3 is a cross-sectional view showing a state where stored ink is reduced in a sub-tank constituting the ink supply system shown in FIG. 2;

FIG. 4 is a sectional view showing a state in which the stored ink is full in the sub tank.

FIG. 5 is a cross-sectional view showing a state in which the pressure reducing release valve is opened in a state where the stored ink is full in the sub tank.

FIG. 6 is a schematic diagram showing another configuration of the ink supply system.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 carriage 6 recording head 7 sub tank 8 ink supply tube (ink supply path) 9 decompression tube 10 capping device 11 waste liquid tank 21 main tank (ink cartridge) 22 decompression chamber 22a decompression chamber lower bottom 23 ink storage chamber 23a ink storage chamber lower bottom 23b Ink supply port 24 Ink supply pipe 25 Float member 27 Seal member (air valve) 28 Valve member (air valve) 28a Valve opening 29 Suction port 32 Decompression opening port 33 Decompression opening tube 34 Decompression opening valve 35 One-way valve 36 Open to atmosphere Mouth 38 suction pump

Claims (12)

[Claims] A recording head mounted on a carriage and reciprocated in the width direction of the recording paper; and a recording head mounted on the carriage together with the recording head to receive ink supply from a main tank via an ink supply path. An ink jet recording apparatus comprising: a sub-tank for supplying ink to a recording head, wherein the sub-tank has a decompression chamber formed therein, and ink is supplied from the main tank to the decompression chamber by decompression of the decompression chamber. In addition, the ink supplied to the decompression chamber is supplied to an ink storage chamber formed in the sub tank via a one-way valve, and the ink is supplied from the ink storage chamber to the recording head. Inkjet recording device. 2. The ink jet recording apparatus according to claim 1, wherein the ink supply path from the main tank to the sub tank is constituted by a flexible ink supply tube. 3. A decompression chamber formed in the sub-tank is provided with decompression control means for stopping a decompression state or a decompression state in accordance with a storage amount of ink supplied from a main tank. 3. The ink jet recording apparatus according to claim 1, wherein the ink is introduced from the main tank into the decompression chamber when the ink jet recording is performed. 4. A decompression control means disposed in a decompression chamber of the sub-tank includes a float member floating by ink stored in the decompression chamber, and an air valve which is opened and closed according to a floating position of the float member. 4. An ink jet recording apparatus according to claim 3, wherein said air valve is connected to a negative pressure generating means. 5. A sub-tank for individually handling each ink is mounted on the carriage, and each air valve provided in a decompression chamber of each sub-tank is connected to one negative pressure generating means. The ink jet recording apparatus according to claim 4, wherein the apparatus is configured. 6. A valve member made of a soft material having a valve opening communicating with the negative pressure generating means, and a valve of the valve member disposed on the float member as the float member moves. 6. The ink jet recording apparatus according to claim 4, comprising a seal member for closing the opening. 7. The ink jet recording apparatus according to claim 1, wherein a lower bottom portion of the ink storage chamber is formed at a position lower in a gravity direction than a lower bottom portion of the decompression chamber in the sub tank. . 8. The one-way valve according to claim 1, wherein the one-way valve for supplying the ink supplied to the decompression chamber to the ink storage chamber is arranged at a lower bottom portion of the decompression chamber or in the vicinity thereof. The ink-jet recording apparatus as described in the above. 9. An ink jet type ink supply system according to claim 1, wherein an ink supply port for supplying ink to said recording head is formed at a lower bottom portion of an ink storage chamber of said subtank or in the vicinity thereof. Recording device. 10. The ink jet recording apparatus according to claim 1, wherein a reduced pressure opening is formed in the reduced pressure chamber to communicate with a reduced pressure opening valve. 11. The ink jet recording apparatus according to claim 10, wherein said pressure reducing release valve is arranged on a carriage. 12. The ink jet recording apparatus according to claim 10, wherein the pressure reducing valve is disposed on the recording apparatus main body side via a flexible pressure reducing tube.