JP2003226022A - Inkjet recorder and method of supplying ink - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To simplify a whole structure and to reduce the cost by reducing a number of components. <P>SOLUTION: A main tank 9a and a sub-tank 7a are connected with an ink supply tube 10. A sealed vessel 61 containing the sub-tank 7a and a pump 69 capable of decompressing the inner section of the sealed vessel 61 are provided on a carriage 61. The pump 69 is driven by the reciprocating operation of the carriage, and then ink is supplied to the sub-tank 7a from the main tank 9a by virtue of the decompressing of the inner section of the sealed vessel 61 by the driving of the pump 69. <P>COPYRIGHT: (C)2003,JPO

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 having two main and sub ink tanks (main tank and sub tank) for supplying ink to a recording head, and an ink supply method therefor.

[0002]

2. Description of the Related Art Generally, an ink jet recording apparatus is a recording head mounted on a carriage and moving in the width direction of a recording sheet, and a sheet for relatively moving the recording sheet in a direction orthogonal to the moving direction of the recording head. And a feeding means. In such an ink jet recording apparatus,
Printing on the recording paper is performed by ejecting ink droplets from the recording head based on the print data. A print head capable of ejecting black, yellow, cyan, and magenta inks, for example, is mounted on the carriage, and not only text printing with black ink but also changing the ejection ratio of each ink enables full-color printing. There is.

Conventionally, in this type of ink jet recording apparatus, a main tank as an ink cartridge is arranged on the apparatus main body side (cartridge holder) and a sub tank is arranged on a carriage on which a recording head is mounted. A device is provided. And
Ink is supplied from each main tank to each sub-tank via an ink supply tube, and ink is further supplied from each sub-tank to each recording head.

In such a recording apparatus, in order to improve throughput, ink is sequentially supplied from each main tank to each sub-tank while printing is performed, and ink is supplied from each sub-tank to each recording head. Functions that provide stable supply are required.

As means for satisfying such a function, for example, by depressurizing the inside of the sub-tank with a diaphragm pump, an ink flow is generated from the main tank to the sub-tank, and ink is supplied (supplied) to the sub-tank. ) Is preferably adopted.

[0006]

However, the above-mentioned ink jet recording apparatus requires a dedicated motor for driving the diaphragm type pump to supply the ink from the main tank to the sub tank, so that the number of parts is reduced. There is a problem in that not only is the bulkiness increased and the entire structure is complicated, but also the cost is increased.

The present invention has been made in order to solve such a technical problem, and it is possible to reduce the number of parts, thereby simplifying the entire structure and reducing the cost. An object of the present invention is to provide a recording device and an ink supply method thereof.

[0008]

SUMMARY OF THE INVENTION An ink jet recording apparatus according to the present invention, which has been made to achieve the above-mentioned object, is equipped with a carriage capable of reciprocating between a printing area and a non-printing area. , An ink jet type recording head that ejects ink droplets corresponding to print data, and two main and sub tanks for supplying ink to this recording head, and these two tanks are connected by an ink supply tube, A hermetic container for accommodating a sub-tank is disposed on the carriage, and a pump capable of depressurizing the hermetic container is disposed. Ink is supplied from the main tank to the sub tank by depressurization.

With such a configuration, when the pressure in the closed container is reduced by driving the pump by the carriage operation, the pressure in the sub tank is reduced accordingly, and the ink flow from the main tank to the sub tank is generated. Supply is made. Therefore, since a dedicated motor conventionally required as a drive source for the ink supply pump is not required, the number of parts can be reduced, and the overall structure can be simplified and the cost can be reduced.

Here, it is preferable that the pump is made of a bag-shaped elastic body which communicates with the inside of the closed container, and expands and contracts by pressing / releasing the fixing member by reciprocating movement of the carriage. With such a configuration, when the pump presses the fixing member during the forward movement of the carriage, the inner volume of the pump decreases due to the contraction of the pump. On the other hand, when the pump releases the pressing force on the fixing member when the carriage returns, the internal volume of the pump increases due to the extension of the pump.

Further, it is desirable to have a first one-way valve capable of discharging the inside air of the closed container to the outside. With this configuration, when the inner volume of the pump decreases due to contraction of the pump, the first one-way valve opens, and the inside air of the closed container is discharged to the outside. Further, it is desirable that a plurality of main and sub tanks are arranged. With this configuration, a plurality of types of ink can be independently supplied from the main tank to the sub tank.

Furthermore, it is desirable that an auxiliary tank reaching the recording head is connected to the ink ejection side of the sub tank. With this configuration, the ink from the sub tank can be temporarily stored in the auxiliary tank when the ink is supplied. It is desirable to have a second one-way valve for supplying ink from the sub tank to the auxiliary tank. Here, it is preferable that the second one-way valve is a check valve, a differential pressure valve, or a self-sealing valve. With this configuration, when the second one-way valve opens during ink supply, ink is supplied from the sub tank to the auxiliary tank.

Further, it is desirable to have a third one-way valve for supplying ink from the main tank to the sub tank. With this configuration, when the third one-way valve opens during ink supply, ink is supplied from the main tank to the sub tank. Further, it is desirable that an air release valve that can open to the atmosphere is arranged in the closed container between the ink supply region and the printing region. With this configuration, if the atmosphere release valve is opened before the carriage moves from the print area side to the ink supply area and from the ink supply area to the print area side, the internal pressure of the closed container becomes atmospheric pressure. To be done.

Furthermore, it is desirable that at least a part of the sub-tank be a flexible film that increases or decreases the internal volume of the tank by elastic deformation due to pressure change in the closed container. With this configuration, when the pressure in the closed container changes, the internal volume of the sub tank increases or decreases due to elastic deformation of the sub tank, and the amount of ink in the sub tank can be changed. Here, it is desirable to have a swelling suppressing member for suppressing swelling due to an increase in the internal volume of the sub tank. With such a configuration, the bulging suppressing member suppresses excessive bulging of the sub tank due to an increase in the internal volume of the tank.

It is also possible to employ a structure in which the sub-tank is formed of a rigid member having a flow port communicating with the inside of the closed container. Because it is configured like this,
The inner volume of the sub tank does not change due to the pressure change in the closed container. Further, it is desirable to have a float member that opens and closes the circulation port according to the amount of ink in the sub tank. With this configuration, when the amount of ink in the sub tank increases, the float member rises and closes the flow port. Further, when the amount of ink in the sub tank decreases, the float member descends to open the circulation port.

On the other hand, according to the ink supply method of the ink jet recording apparatus of the present invention, a carriage capable of reciprocating between the printing area and the non-printing area is mounted on the carriage, and ink drops are ejected corresponding to the printing data. An ink jet type recording head for discharging and a main and sub two tanks for supplying ink to the recording head are provided, these tanks are connected by an ink supply tube, and a closed container for accommodating the sub tank is mentioned above. A method for supplying ink to an ink jet recording apparatus, comprising: arranging on a carriage, and arranging a pump capable of depressurizing the inside of the closed container, wherein when supplying ink from the main tank to the sub tank, It is characterized in that the inside of the closed container is depressurized by driving the pump by the moving operation.

According to this method, when the pressure in the closed container is reduced by driving the pump by the carriage operation,
Along with this, the pressure inside the sub tank is reduced, and an ink flow is generated from the main tank to the sub tank to supply ink. Therefore, a dedicated motor that has been conventionally required as a drive source for the ink supply pump is not required, so that the number of parts can be reduced, and an ink supply method that can achieve simplification of the entire structure and cost reduction can be obtained. it can.

Here, it is preferable that the closed container is opened to the atmosphere before ink is supplied from the main tank to the sub tank. According to such a method, the atmosphere opening valve is opened before the ink is supplied from the main tank to the sub tank, and the internal pressure of the closed container is set to the atmospheric pressure.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION An ink jet recording apparatus and an ink supply method for the same according to the present invention will be described below.
A description will be given based on the embodiment shown in the drawings. First, referring to FIG. 1 and FIG.
An explanation will be given using (b). FIG. 1 is a plan view showing the outline of the basic configuration of an inkjet recording apparatus according to an embodiment of the present invention. 2A and 2B are sectional views showing a sub tank of the ink jet recording apparatus according to the embodiment of the present invention. A carriage indicated by reference numeral 1 in the drawing is mounted on a timing belt 3 driven by a carriage motor 2. Then, it is configured to be guided by the guide member 4 to reciprocate in the longitudinal direction of the paper feeding member 5, that is, in the main scanning direction which is the width direction of the recording paper. In addition, on the lower surface of the carriage 1,
Although not shown in FIG. 3, an ink jet recording head 6 (shown in FIG. 2) is mounted facing the paper feeding member 5.

The printing by the recording head 6 on the printing paper (not shown) on the paper feeding member 5 is performed in the main scanning of the carriage 1. The area on the paper feeding member 5 where this printing is performed is " It is called "printing area". On the other hand, an area where printing is not performed is called a "non-printing area".

On the carriage 1, sub tanks 7a to 7d for supplying ink from a main tank (described later) to the recording head 6 are mounted via a hermetically sealed container 61. Four sub tanks 7a to 7d are provided corresponding to the respective inks of black, yellow, magenta and cyan in order to temporarily store the respective inks therein. Each ink is supplied from the main tanks 9a to 9d as ink cartridges loaded in the cartridge holder 8 arranged in the apparatus main body, through the ink supply tube 10 made of a flexible material. There is. Further, it is configured to supply four auxiliary tanks 62a to 62d on the carriage 1 through the ink supply tube 10a.

Further, as shown in FIGS. 2 (a) and 2 (b), the sub-tanks 7a to 7d are partially formed of a flexible film. The internal volume is increased or decreased by the elastic deformation due to the pressure change in the closed container 61, and the ink amount in the sub tanks 7a to 7d is changed. In addition, the sub tanks 7a to 7d
A swelling suppressing member 63 for suppressing swelling due to an increase in the internal volume is disposed in the. As a result, the excessive expansion of the sub tanks 7a to 7d due to the increase in the tank internal volume is suppressed. In the present embodiment, the sub tank 7a
Although the case where a part of 7d is formed by the flexible film has been described, the present invention is not limited to this, and the whole may be formed by the flexible film.

On the other hand, capping means 11 capable of sealing the nozzle forming surface of the recording head 6 is arranged in a non-printing area (home position) on the moving path of the carriage 1. A head cap 11a made of a flexible material such as rubber capable of sealing the nozzle forming surface of the recording head 6 is arranged on the upper surface of the capping means 11. When the carriage 1 moves to the home position, the head cap 11a can seal the nozzle forming surface of the recording head 6.

The head cap 11a functions as a lid for sealing the nozzle forming surface of the recording head 6 during the rest period of the recording apparatus and preventing the nozzle openings from drying. Although not shown in the drawing, one end of a tube of a suction pump (tube pump) is connected to the head cap 11a, and a negative pressure generated by the suction pump is applied to the recording head 6 to cause the recording head 6 to operate. A cleaning operation for sucking and discharging the ink from 6 is executed. And the capping means 1
A wiping member 12 made of an elastic material such as rubber is arranged adjacent to the print area side of No. 1, and the nozzle forming surface of the recording head 6 can be wiped and cleaned as needed.

Since nozzle cleaning is performed in the area on the head cap 11a, the area on the head cap 11a in the moving range of the recording head 6 in the main scanning direction is called a "cleaning area". In the main scanning of the recording head 6 (carriage 1), the main tank 9a to the non-printing area side above the head cap 11a.
Since the ink is supplied from the 9d to the sub tanks 7a to 7d, this area is referred to as an "ink supply area".

Next, the ink supply system of the recording apparatus constructed as described above will be described with reference to FIGS. FIG. 3 is a sectional view schematically showing the configuration of the ink supply system in the recording apparatus of FIG. 4A and 4B are cross-sectional views showing the one-way valve in the ink supply system. In FIG. 3, a closed container denoted by reference numeral 61 is arranged on the carriage 1 (shown in FIG. 1). The closed container 61 is the sub tank 7a to 7d.
Internal space 61a for accommodating (only the sub tank 7a is shown)
It is formed by a rectangular box-shaped rigid member having.
Further, the airtight container 61 is provided with the first circulation port 61b to the third circulation port 61d opening inside and outside the internal space 61a and the tube insertion holes 61e and 61f through which the ink supply tubes 10 and 10a are inserted. There is.

A circulation portion 64, which is open to the atmosphere, is arranged at the outer peripheral edge of the first circulation port 61b. A first one-way valve 65 is arranged in the middle of the circulation portion 64. Then, the inside air of the closed container 61 can be discharged to the outside by driving (forward movement) of a pump (described later).

The one-way valve 65 is formed by a check valve composed of a casing 66 and a valve body 67 as shown in FIGS. 4 (a) and 4 (b). The casing 6
6 has a partition wall 66a which defines the inside thereof into two chambers, and a circulation port 66b which penetrates the partition wall 66a, and is communicated with the circulation portion 64. The valve body 67 has a seat portion 67a which can be seated on the opening peripheral edge (partition wall 66a) of the circulation port 66b, and is biased by a spring 68 in a direction such that the seat portion 67a is always seated on the partition wall 66a. Has been done. The one-way valve 65 is the closed container 6
When the internal pressure of 1 becomes higher than the atmospheric pressure, the seating portion 67a is separated from the partition wall 66a against the elastic force of the spring 68,
It is configured to open the valve from the closed state shown in FIG. 4 (a) to the state shown in FIG. 4 (b). Further, when the internal pressure of the closed container 61 becomes lower than the atmospheric pressure, the seating portion 67a is seated on the partition wall 66a by the elastic force of the spring 68, and as shown in FIG.
It is configured to close the valve from the open state shown in (b) to the state shown in FIG.

The main tanks 9a to 9d to the sub-tank 7 are provided along the outer peripheral edge of the second circulation port 61c.
In order to supply ink to a to 7d, the closed container 61
A pump 69 capable of reducing the pressure inside is attached. A first fixing member 70 having a receiving surface 70a perpendicular to the horizontal axis is provided on the non-printing area side (left side in FIG. 3) of the pump 69. In FIG. 3, the pump 69 and the first fixing member 70 are arranged at positions where the recording head 6 (closed container 61) is moved in the left-right direction parallel to the plane of FIG. However, the pump 69 and the first fixing member 70 move the recording head 6 in a direction perpendicular to the paper surface of FIG. It is arranged at such a position that the pump is driven.

The pump 69 is formed of a bag-shaped elastic body made of, for example, a bellows and communicating with the inside of the closed container 61. Then, the first fixing member 70 (receiving surface 70a) due to the reciprocating movement of the carriage 1 when ink is supplied.
It is configured to expand / contract in the horizontal axis direction by pressing / releasing the pressure to increase / decrease its internal volume. That is,
When the carriage 1 moves forward to the non-printing area side during ink supply, the pump 65 presses the first fixing member 70 and contracts (compresses) in the horizontal axis direction, and the internal volume thereof decreases. on the other hand,
When the carriage 1 returns to the print area side when ink is supplied, the pump 65 releases the pressure on the first fixing member 70 and extends (elastically returns) in the horizontal axis direction, and the internal volume increases.

A cylindrical casing 71 having a bottom and communicating with the inside of the closed container 61 is disposed at the outer peripheral edge of the third circulation port 61d. In this casing 71,
A circulation port 71a that opens to the atmosphere is provided. Further, inside the casing 71, an atmosphere opening valve 72 capable of opening and closing the circulation port 71a is arranged.

The atmosphere opening valve 72 is formed by a check valve composed of a valve body 73 and an operator 74. The valve body 73 has a seating portion 73a that can be seated on the inner peripheral edge (sealing surface) of the circulation port 71a.
It is biased by a spring 75 in such a direction that a is always seated on the sealing surface. The manipulator 74 is inserted through the circulation port 71a and integrally provided on the lower surface of the valve body 73. Then, the atmosphere release valve 72 is
It is configured to open to the atmosphere between the ink supply area and the printing area.

That is, when the operator 74 pushes the cam surface 76a of the second fixing member 76 by the movement of the carriage 1, the reaction force is received from the cam surface 76a. With this,
The valve body 73 resists the elastic force of the spring 75 and the operator 74
Since the seat 73a moves upward together with the flow port 71,
The atmosphere opening valve 72 opens apart from the inner peripheral edge of the opening a, as indicated by the chain double-dashed line in FIG. Thus, when the atmosphere opening valve 72 is opened before the carriage 1 moves from the print area side to the ink supply area and from the ink supply area to the print area side, the internal pressure of the closed container 61 becomes atmospheric pressure. In addition, in FIG. 3, the second fixing member 76 is
It is shown that the recording head 6 (closed container 61) is moved in the left-right direction parallel to the paper surface of FIG. 3 to perform the opening / closing operation of the atmosphere opening valve 72, but this is schematic. Specifically, the second fixing member 76 is located at a position where the recording head 6 is moved in the direction perpendicular to the paper surface of FIG. 3 to open / close the atmosphere opening valve 72. It is arranged.

When the pressing of the operator 74 against the second fixing member 76 is released, the valve body 73 is moved downward (returned) by the elastic force of the spring 75, and the seating portion 73a is moved. It is seated on the inner peripheral edge of the flow opening 71a, and the atmosphere opening valve 72 is closed as shown by the solid line in FIG.

On the other hand, the tube insertion holes 61e, 61f
A second one-way valve 77 and a third one-way valve 78, which are check valves as shown in FIGS. 4A and 4B, are provided in the middle of the ink supply tubes 10 and 10a inserted in Each is arranged. That is, the ink supply tube 1
A second one-way valve 77 is arranged in the middle of 0a, and a third one-way valve 78 is arranged in the middle of the ink supply tube 10. Then, by opening the third one-way valve 78 by depressurizing the inside of the closed container 61, the main tanks 9a ...
The ink from 9d is supplied to the sub tanks 7a to 7d. Further, the sub tank 7 is opened by opening the second one-way valve 77 due to the generation of negative pressure on the recording head 6 side.
Ink from a to 7d can be supplied to the auxiliary tanks 62a to 62d (recording head 6).

Although the second one-way valve 77 is arranged in the middle of the ink supply tube 10a, it may be arranged in the auxiliary tanks 62a to 62d. Further, although the case where the third one-way valve 78 is arranged near the main tanks 9a to 9d has been described, the main tank 9
It may be housed in the a-9d or may be arranged in the vicinity of the sub-tanks 7a-7d.

Next, the ink supply method (ink supply from the main tank to the sub tank) of the ink jet recording apparatus in this embodiment will be described with reference to FIGS.
An explanation will be given using (d). 5A to 5D are views for explaining the ink supply method in the inkjet recording apparatus according to the embodiment of the present invention, and the configuration is schematically shown. The ink supply method is
"Valve opening valve opening operation" and "Pump contraction operation"
And the "pump extension operation" are sequentially performed, and these steps will be sequentially described.

[Opening Operation of Atmosphere Release Valve] First, referring to FIG.
As shown in (a), the cleaning area (right side in FIG. 5) is moved in the ink supply area (left side) toward the first fixing member 70 (direction of arrow a1). In this case, when the carriage 1 moves forward, the operator 74 causes the second fixing member 7 to move.
It rises by riding up 6. That is, when the operating element 74 rides on the cam surface 76 a of the second fixing member 76, the operating element 74 receives an upward reaction force from the second fixing member 76 and accordingly resists the elastic force of the spring 75. The valve body 73 moves up together with the operator 74. Therefore, the seating portion 73a of the valve body 73 separates from the inner opening peripheral edge of the circulation port 71a (the atmosphere opening valve 72 opens), and the third circulation port 61d communicates with the circulation port 71a. As a result, the closed container 61 is opened to the atmosphere through the casing 71, and the internal space 61
The pressure of a is set to atmospheric pressure.

Next, the carriage 1 is further moved in the direction of arrow a1. In this case, when the carriage 1 moves forward,
The operator 74 gets over the second fixing member 76. Therefore, the valve body 73 descends together with the operator 74 due to the elastic force of the spring 75. As a result, the seat portion 7 of the valve body 73
3a is seated on the inner peripheral edge of the flow opening 71a, and the atmosphere opening valve 72 is closed. Further, the carriage 1 is arranged in the ink supply region by the forward movement.

[Pump Contraction Operation] First, as shown in FIG. 5B, the carriage 1 is set in the ink supply region.
The (closed container 61) is moved forward toward the first fixing member 70 (direction of arrow a1). In this case, when the carriage 1 moves forward, the tip portion (end portion on the non-printing area side) of the pump 69 contacts the receiving surface 70a of the first fixing member 70.

Next, as shown in FIG. 5C, the carriage 1 is further moved in the direction of arrow a1. In this case, when the carriage 1 moves forward, the pump 69 contracts (compresses) in the horizontal axis direction. Therefore, the pump 69 (the closed container 6
The internal volume of 1) decreases, and the pressure in the closed container 61 (internal space 61a) increases accordingly. As a result, the first one-way valve 65 is opened, and the inside air of the closed container 61 flows into the circulation portion 6
4 is discharged into the atmosphere.

"Pump Expansion Operation" First, the carriage 1 (closed container 61) is moved back to the print area side (right side in FIG. 5) in the ink supply area. In this case, when the carriage 1 returns, the pump 69 elastically returns and extends in the horizontal axis direction. Therefore, the pump 69 (the closed container 6
The internal volume of 1) increases, and the pressure in the closed container 61 decreases accordingly. As a result, the first one-way valve 65 is closed.

Next, as shown in FIG. 5D, the carriage 1 is further moved back to the print area side (direction of arrow a2). In this case, when the carriage 1 returns, the pump 69
Extends further in the horizontal axis direction. Therefore, the pump 6
The internal volume of 9 (closed container 61) increases, and the pressure in the closed container 61 falls. Along with this, the sub tanks 7a to 7d
Partially elastically deforms and swells into the closed container 61 (internal volume of the sub-tanks 7a to 7d increases), and the sub-tanks 7a to 7d
The pressure inside drops. As a result, the third one-way valve 78
Is opened, and the main tanks 9a to 9d to the sub tank 7a
Ink supply is performed by generating an ink flow in 7d.

In this way, the ink from the main tanks 9a to 9d is transferred to the main tanks 7a to 7d through the steps of "opening operation of atmosphere release valve", "contracting operation of pump" and "expanding operation of pump". Can be supplied. Therefore, in the present embodiment, a dedicated motor conventionally required as a drive source for the ink supply pump is not required, so that the number of parts can be reduced, the overall structure can be simplified, and the cost can be reduced. You can

In this embodiment, the sub tank 7
The ink is supplied from the a to 7d to the auxiliary tanks 62a to 62d by generating a negative pressure on the recording head side during printing and opening the second one-way valve 77. Also,
In the present embodiment, the case has been described in which the second one-way valve 77 is a check valve, but the present invention is not limited to this, and the differential pressure valve 81 as shown in FIG. 6 or FIG. The self-sealing valve 91 as shown in FIG.

The differential pressure valve 81 shown in FIG. 6 has a through hole 81a and is formed of an elastically deformable film piece such as an elastomer. The differential pressure valve 81 is biased in the valve closing direction by a spring 83, and its outer peripheral edge is fixed to a casing 84. Then, when the pressure on the recording head side decreases, the differential pressure valve 81 separates from the valve seat portion 84a (the through hole 81a opens) against the biasing force of the spring 83, so that the sub tanks 7a to 7d (shown in FIG. 1). ) From the auxiliary tanks 62a to 62d through the through holes 81a.
(Shown in FIG. 1). Further, when the ink pressure on the recording head side rises to a predetermined value, the differential pressure valve 81 is seated on the valve seat portion 84a by the urging force of the spring 83, and the flow of ink is cut off.

On the other hand, the self-sealing valve 91 shown in FIG. 7 has a valve body 92 having a substantially T-shaped cross section, and a part of this valve body 92 is inserted into the through hole 93a of the partition wall 93 so as to be inside the casing 94. It is housed freely in and out. The valve body 92 has a through hole 93a.
Seating portion 92 that can be seated on the peripheral edge of the opening (sealing portion 93b)
a, and is constantly urged by a spring 95 in a direction such that the seat portion 92a is seated on the seal portion 93b. Further, film members 96 and 97 for sealing the ink supply chamber 94a and the pressure chamber 94b in the casing 94 are attached to both sides of the valve body 92.

In such a self-sealing valve 91, the repulsive force W1 of the spring 95 and the ink supply chamber 9 in the non-printing state.
The ink pressure P1 in 4a is applied to the valve body 92 to close the valve. Further, in the printing state, the film member 97 is displaced toward the partition wall 93 side as the ink in the pressure chamber 94b is consumed, and the valve body 92 is pressed by this displacement force Wd. Then, when the ink in the pressure chamber 94b is further consumed,
Negative pressure P2 is generated in the pressure chamber 94b. In this case, when the force relationship between the ink pressure P1, the negative pressure P2, the elastic force W1 and the displacement force Wd is P2> W1 + P1 + Wd, the valve body 92 is formed.
The (seating portion 92a) is separated from the seal portion 93b, and the self-sealing valve 91 is opened.

Besides, in the present embodiment, the case where a part of the sub tanks 7a to 7d is formed of a flexible film has been described, but the present invention is not limited to this.
As shown in FIG. 8, the sub tank 101 (only one is shown) may be formed of a rigid member. The sub-tank 101 shown in FIG. 8 is housed in a closed container 61. The sub-tank 101 has a flow port 1 communicating with the inside of the closed container 61.
01a. In the sub tank 101,
The float member 102 is rotatably housed. The float member 102 has a valve body 102a that opens and closes the circulation port 101a according to the amount of ink in the sub tank 101.

When the amount of ink in the sub-tank 101 increases, the valve member 102a closes the flow port 101a due to the rising (clockwise rotation) of the float member 102. Further, when the amount of ink in the sub tank 101 becomes small, the valve member 102 a is moved to the flow port 101 by the descent (counterclockwise rotation) of the float member 102.
It is configured to open a. Main tanks 9a to 9d (illustrated in FIG. 1) for the sub-tank 101
Ink supply from the same as in the above case (when the sub-tank is formed by a flexible film),
This process is performed through the steps of "valve opening operation of atmosphere release valve 72", "contraction operation of pump 69", and "expansion operation of pump 69".

Further, although the case where the sub-tanks 7a to 7d are housed in the single closed container 61 has been described in the present embodiment, the present invention is not limited to this, and a plurality of closed containers (the same number as the sub-tanks). May be prepared, and a corresponding sub tank may be housed in each of these closed containers.

[0052]

As is apparent from the above description, according to the ink jet recording apparatus and the ink supply method for the same according to the present invention, the number of parts can be reduced, the structure can be simplified and the cost can be reduced. Can be planned.

[Brief description of drawings]

FIG. 1 is a plan view showing a basic configuration of an ink jet recording apparatus according to an embodiment of the present invention.

2A and 2B are cross-sectional views showing a sub tank of the ink jet recording apparatus according to the embodiment of the present invention.

3 is a sectional view schematically showing an ink supply system from an ink cartridge to a recording head in the recording apparatus shown in FIG.

4A and 4B are cross-sectional views showing a one-way valve used in the ink supply system shown in FIG.

5A to 5D are schematic diagrams shown for explaining an ink supply method of an ink jet recording apparatus according to an embodiment of the present invention.

FIG. 6 is a cross-sectional view showing another one-way valve (1) used in the ink jet recording apparatus according to the embodiment of the invention.

FIG. 7 is a sectional view showing another one-way valve (2) used in the ink jet recording apparatus according to the embodiment of the invention.

FIG. 8 is a cross-sectional view showing another sub-tank used in the ink jet recording apparatus according to the embodiment of the invention.

[Explanation of symbols]

1 Carriage 2 Carriage Motor 3 Timing Belt 4 Guide Member 5 Paper Feeding Member 6 Recording Heads 7a to 7d Sub Tank 8 Cartridge Holders 9a to 9d Main Tank (Ink Cartridge) 10, 10a Ink Supply Tube 61 Sealed Container 61a Internal Space 61b First Distribution Port 61c Second circulation port 61d Third circulation port 61e, 61f Tube insertion holes 62a to 62d Auxiliary tank 63 Bulging suppression member 64 Circulation part 65 First one-way valve 69 Pump 70 First fixing member 71 Receiving surface 72 Open to the atmosphere Valve 76 Second fixing member 76a Cam surface 77 Second one-way valve 78 Third one-way valve

Claims (15)

[Claims] 1. A carriage capable of reciprocating between a printing area and a non-printing area, an ink jet recording head mounted on the carriage for ejecting ink droplets corresponding to print data, and an ink for the recording head. And two main and sub tanks for supplying the ink, these tanks are connected by an ink supply tube, and a closed container for accommodating the sub tank is placed on the carriage, and the inside of the closed container can be depressurized. An ink jet recording apparatus, wherein a different pump is arranged, the pump is driven by the reciprocating movement of the carriage, and ink is supplied from the main tank to the sub tank by the pressure reduction in the closed container due to the driving. 2. The pump is made of a bag-shaped elastic body that communicates with the inside of the closed container, and expands and contracts by pressing / releasing the pressing of a fixing member by reciprocating movement of the carriage. The described inkjet recording device. 3. The ink jet recording apparatus according to claim 1, further comprising a first one-way valve capable of discharging the inside air of the closed container to the outside. 4. The ink jet recording apparatus according to claim 1, wherein a plurality of main and sub tanks are arranged. 5. The ink jet recording apparatus according to claim 1, wherein an auxiliary tank reaching the recording head is connected to an ink ejection side of the sub tank. 6. The ink jet recording apparatus according to claim 1, further comprising a second one-way valve for supplying ink from the sub tank to the auxiliary tank. . 7. The ink jet recording apparatus according to claim 6, wherein the second one-way valve is any one of a check valve, a differential pressure valve, and a self-sealing valve. 8. The ink jet recording apparatus according to claim 1, further comprising a third one-way valve for supplying ink from the main tank to the sub tank. . 9. The air release valve capable of opening to the atmosphere between the ink supply area and the printing area is arranged in the closed container, according to any one of claims 1 to 8. The described inkjet recording device. 10. A flexible film, wherein at least a part of the sub-tank is a flexible film that increases or decreases the internal volume of the tank by elastic deformation due to a pressure change in the closed container. Inkjet recording apparatus described in any one of 1. 11. The ink jet recording apparatus according to claim 10, further comprising a swelling suppressing member for suppressing swelling due to an increase in the internal volume of the sub tank. 12. The ink jet recording according to claim 1, wherein the sub-tank is formed by a rigid member having a flow port communicating with the inside of the closed container. apparatus. 13. The ink jet recording apparatus according to claim 12, further comprising a float member that opens and closes the circulation port according to the amount of ink in the sub tank. 14. A carriage capable of reciprocating between a printing area and a non-printing area, an ink jet recording head mounted on the carriage and ejecting ink droplets corresponding to print data, and an ink for the recording head. And two main and sub tanks for supplying the ink, these tanks are connected by an ink supply tube, and a closed container for accommodating the sub tank is placed on the carriage, and the inside of the closed container can be depressurized. An ink supply method for an ink jet recording apparatus in which a pump is arranged, wherein when the ink is supplied from the main tank to the sub tank, the pressure inside the closed container is reduced by driving the pump by the movement operation of the carriage. An ink supply method for an inkjet recording apparatus, comprising: 15. The ink supply method for an ink jet recording apparatus according to claim 14, wherein the airtight container is opened to the atmosphere before ink is supplied from the main tank to the sub tank.