JP2003159809A - Method of filling ink and inkjet recorder - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of filling ink and an inkjet recorder capable of improving a deaeration degree of ink at the time when the ink in a main ink tank is initially filled in a sub-ink tank. <P>SOLUTION: A negative pressure is applied to a recording head by closing an opening/closing means provided to a fluid passage between the main tank and the sub-tank to crush the sub-tank by an atmospheric pressure and the air in the sub-tank is discharged so that the ink is allowed to enter the sub-tank from the main tank by opening the opening/closing means. The ink and the air in the sub-tank is discharged therefrom similarly to the above, and then the ink is allowed to flow into the sub-tank so that the sub-tank is filled with the ink. As a result, the air in the fluid passage from the opening/closing means to the main tank is discharged to the outside by the second operation for the negative pressure so that it is possible to remove the air in the fluid passage from the recording head to the main tank and to improve the deaeration degree of the ink filled in the sub-tank. <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 a method for filling ink in a sub ink tank for temporarily storing ink supplied from a main ink tank in which ink is stored, and an ink jet recording apparatus.

[0002]

2. Description of the Related Art Generally, one type of ink jet recording apparatus is used.
The ink jet printer, which is the third type, prints by reciprocating a recording head that pressurizes ink supplied from an ink tank and ejects ink droplets in the width direction of the paper. Inkjet printers capable of printing a large amount by such a method are large-capacity main ink tanks for each color (hereinafter referred to as main tanks).
And a small-capacity sub-ink tank for each color (hereinafter referred to as a sub-tank), which is connected to each main tank through a pipe and is formed in a bag-like shape having air-tightness with a flexible material having a flexible volume Is equipped with.

The method of initially filling the ink into the sub-tank of the ink jet printer having the above-mentioned structure is as follows.
The electromagnetic valve disposed between the sub tank and the main tank is closed, the recording head is capped and sucked, and the air in the sub tank is discharged. Next, the electromagnetic valve is opened to supply the ink in the main tank to the sub tank for filling.

[0004]

In the ink filling method described above, the air in the flow path from the recording head to the electromagnetic valve via the sub-tank can be discharged by a suction operation, but from the electromagnetic valve to the main tank. The air in the flow path between and remains in the sub tank together with the ink from the main tank and cannot be discharged.
Since the recording head pressurizes the ink and ejects ink droplets, if the ink contains bubbles,
There is a risk that the pressure of the ink will drop and the ejection performance of the ink drops will also drop.

The present invention has been made in view of the above problems, and an object thereof is to improve the degree of deaeration of ink when the ink is initially filled from the main ink tank to the sub ink tank. It is an object of the present invention to provide an ink filling method and an ink jet recording apparatus capable of achieving the above.

[0006]

In order to achieve the above object, in the ink filling method according to the first aspect of the present invention, a main ink tank, which is connected to a pipe and stores ink, and the pipe is opened and closed. By a method of opening and closing means, a sub ink tank that temporarily stores the ink, and a recording head that ejects ink droplets, and by initially filling the sub ink tank with the ink from the main ink tank. Then, the opening / closing means is closed to apply a negative pressure to the recording head, the sub ink tank is crushed by the atmospheric pressure to discharge the air in the sub ink tank, and the opening / closing means is opened to open the opening / closing means. The ink is caused to flow from the main ink tank to the sub ink tank, the opening / closing means is closed to apply a negative pressure to the recording head, and the sub ink tank is enlarged. It is characterized in that the ink and air in the sub ink tank are crushed by pressure to be discharged, and the opening / closing means is opened to allow the ink to flow from the main ink tank to the sub ink tank for filling. . As a result, the air in the flow path between the print head and the sub ink tank to the opening / closing means is discharged by the first negative pressure action, and the air from the opening / closing means to the main ink tank is discharged by the next negative pressure action. Since the air in the flow path can be discharged, the air in the flow path from the print head to the main ink tank can be eliminated, and the degree of deaeration of the ink filled in the sub ink tank is improved. Can be made.

According to a second aspect of the present invention, in the ink filling method according to the first aspect, after the step according to the first aspect is completed, the opening / closing means is closed and a predetermined amount of ink in the sub ink tank is closed. The ink is sucked and discharged, and the opening / closing means is opened to allow the ink to flow from the main ink tank to the sub ink tank for filling. As a result, the ink flowing into the sub ink tank in the crushed state may flow in at a high speed and may foam to deteriorate the degree of degassing.However, a predetermined amount of the ink in this state is discharged. Then, by inflowing new ink, the degree of deaeration of the ink filled in the sub ink tank can be further improved.

According to a third aspect of the invention, there is provided the ink filling method according to the first or second aspect, wherein
After the step described in (4) is completed, the opening / closing means is closed to suck the ink in the sub ink tank to flow into the flow path between the sub ink tank and the print head and the print head to fill the ink. It is characterized by that. Further, in the invention according to claim 4, a main ink tank connected to a pipe and storing the ink, an opening / closing means for opening and closing the pipe, and a sub ink tank for temporarily storing the ink, A method for initially filling the sub ink tank with the ink from the main ink tank, the method comprising: a recording head for ejecting ink droplets; closing the opening / closing means to apply a negative pressure to the recording head. , The sub ink tank is crushed at atmospheric pressure to discharge the air in the sub ink tank, the opening / closing means is opened to allow the ink to flow from the main ink tank to the sub ink tank, The opening / closing means is closed to suck the ink in the sub ink tank to flow into the flow path between the sub ink tank and the recording head and the recording head. It is characterized by filling Te. As a result, in particular, the air in the recording head can be completely discharged, so that the ejection characteristics of the ink droplets can be maintained in a high performance state.

According to a fifth aspect of the present invention, in the ink filling method according to any one of the first to third aspects, the opening / closing means is closed to apply a negative pressure to the recording head, and the sub ink tank is operated. Is squeezed by the atmospheric pressure to discharge the ink and air in the sub ink tank, open the opening / closing means, and flow the ink from the main ink tank to the sub ink tank to fill the ink. Is performed multiple times. As a result, the air in the flow path from the print head to the main ink tank can be completely eliminated, and the degree of deaeration of the ink filled in the sub ink tank can be further improved.

According to a sixth aspect of the present invention, in the ink filling method according to any one of the first to fifth aspects, the main ink tank is arranged below the sub ink tank. It is characterized by being pressurized. According to a seventh aspect of the invention, in the ink filling method according to any one of the first to fifth aspects, the main ink tank is arranged above the sub ink tank. . As a result, not only is the method of supplying pressure to the sub ink tank by pressurizing the main ink tank, but also the method of supplying ink with a water head difference between the main ink tank and the sub ink tank. However, it is possible to improve the degassing degree of the ink filled in the sub ink tank by eliminating the air in the flow path from the recording head to the main ink tank.

According to an eighth aspect of the present invention, in the ink filling method according to any one of the first to seventh aspects, the sub ink tank is made of a flexible material, and the flexible materials are It is characterized in that an adhesion preventing member for preventing the adhesion is provided. Thus, the adhesion preventing member can prevent the flexible materials forming the sub ink tank from adhering to each other, so that all areas in the sub ink tank have the same negative pressure, and The remaining air can be eliminated.

The invention according to claim 9 is characterized by an ink jet recording apparatus using the ink filling method according to any one of claims 1 to 8. As a result, it is possible to provide an ink jet recording apparatus that achieves each of the above actions.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a perspective view showing a structural example of an ink jet printer according to an embodiment of an ink jet recording apparatus of the present invention. In this inkjet printer 1, a window 3 having a width through which a sheet can pass is formed by a frame 2. A carriage 4, which is reciprocally movable in the main scanning direction, is mounted above the window 3, a recording head 5 for ejecting ink droplets is provided, and a paper is supported below the window 3. A paper guide member 6 is provided. Further, on the right side of the frame 2 in the figure, an operation panel 7 for operating the built-in control unit is arranged, and on the left side of the frame 2 in the figure, an openable cover 8 is covered. Detachable main tank 10
A main tank storage section 9 for storing B, 10Y, 10C, and 10M (see FIG. 2) is provided.

FIG. 2 is a diagram showing details of the recording section of the ink jet printer 1 shown in FIG. The carriage 4 includes a carriage drive motor 32 via a timing belt 31.
Is configured to be reciprocally driven. On the carriage 4, a recording head 5a that ejects black ink droplets supplied from the ink supply system 40 and a recording head 5b that ejects yellow, cyan, and magenta ink droplets, respectively.
Is installed.

The ink supply system 40 includes main tanks 10B, 10Y, 10 which store inks of respective colors.
C, 10M and main tanks 10B, 10Y, 10C,
Sub tanks 20B, 20Y, 20C, and 20M that temporarily store the inks of the respective colors from 10M, and main tanks 10B, 10Y, and 10 that are disposed in the main tank storage section 9.
Pressure chambers 41B, 41Y, 41C for accommodating C, 10M,
41M is provided. And each pressurizing chamber 41B, 4
1Y, 41C, 41M are pressure detectors 51B, 51Y,
51C, 51M and solenoid valves 52B, 5 for releasing pressure
It is connected to the discharge port 53a of the pressurizing pump 53 via 2Y, 52C and 52M.

Further, the main tanks 10B, 10Y, 1
0C, 10M and sub tanks 20B, 20Y, 20C, 2
Ink transport tubes 42B, 42Y, 42C connecting 0M,
42M and ink transport tubes 42B, 42Y, 42C, 42
Electromagnetic valves 43B, 43Y, 43 connected in the middle of M
C, 43M and sub tanks 20B, 20Y, 20C, 2
Ink supply tubes 44B, 44Y, 44C and 44M for connecting the recording heads 5a and 5b to the recording heads 0M are arranged.

In the non-printing inclination on the right side of the paper guide member 6 in the figure, the clogging caused by ink drying of the recording heads 5a and 5b during non-printing is prevented and the recording heads 5a and 5b are prevented.
A capping device 46 that applies a negative pressure to the recording heads 5a and 5b by a suction pump 45 is provided for the initial filling of ink into b and elimination of clogging. Further, the paper guide member 6 is provided with a support plate 6a having pores on the surface facing the paper in order to apply a negative pressure from the suction port 47a of the suction pump 47 to the paper to fix the paper. It is set up.

FIG. 3 shows the main tank 10 (10B,
10Y, 10C, 10M) is a perspective view showing a detailed structure. The main tank 10 is made of a flexible material having a volume changeable flexibility, and is formed in a bag shape having a size capable of flexibly following the change of the ink amount, for example, an airtight capacity of about 1000 cc. A connection port 10a that can be connected to the ink transport pipes 42B, 42Y, 42C, and 42M is provided on one short side, and the central portion on the other short side prevents unnecessary expansion. Is welded to
A gusset 10b is provided on the long side to expand the volume as much as possible.

As a constituent material of the main tank 10, in order to secure a gas barrier property, for example, two films with an aluminum foil as an intermediate layer, for example, a nylon film on the outside,
An aluminum laminate film with the inside sandwiched by polyethylene films can be used. Furthermore, silicon oxide is deposited on the surface of a polymer film such as polyethylene terephthalate (PET) or nylon, which has transparency and light transmission properties in addition to flexibility and air permeability, to form a silicon oxide layer. It is also possible to use a light transmissive film formed by laminating a polymer film such as polyethylene having excellent weldability.

FIGS. 4A and 4B show the sub-tank 2 described above.
It is a top view and a BB line sectional view showing a detailed structure of 0 (20B, 20Y, 20C, 20M). This sub tank 2
0 is an ink pack 21 in which ink is stored,
The ink pack 21 includes an adhesion preventing member 22 that prevents the inner surfaces of the ink pack 21 from adhering to each other, an ink amount detection unit 23 that detects the amount of ink in the ink pack 21, and a fixing plate 24 that fixes the ink pack 21.

FIG. 5 is a perspective view showing the detailed structure of the ink pack 21. The ink pack 21 is made of a flexible material having a volume changeable flexibility, and has a size capable of flexibly following a change in the ink amount, for example, 5 cc to 300.
It is formed into a bag having an airtight capacity of about cc. The ink transport pipes 4 are provided on the opposite sides, respectively.
2B, 42Y, 42C, 42M connectable inlet 21
a and ink supply tubes 44B, 44Y, 44C, 4
An outlet 21b that can be connected to 4M is provided.

As a constituent material of the ink pack 21, in order to secure a gas barrier property, for example, two films with an aluminum foil as an intermediate layer, for example, a nylon film on the outside,
An aluminum laminate film with the inside sandwiched by polyethylene films can be used. Furthermore, silicon oxide is deposited on the surface of a polymer film such as polyethylene terephthalate (PET) or nylon, which has transparency and light transmission properties in addition to flexibility and air permeability, to form a silicon oxide layer. It is also possible to use a light transmissive film formed by laminating a polymer film such as polyethylene having excellent weldability.

As shown in FIG. 4, the ink amount detecting means 23 is adhered to one surface side of the ink pack 21, and the other surface side of the ink pack 21 is adhered to the fixing plate 24. The ink amount detecting means 23 is the ink pack 2
Adhesive portion 23 formed in a substantially plate shape and adhered to one surface side of No. 1
a and a detection portion 23b integrally formed in a substantially plate shape under the adhesive portion 23a so as to be orthogonal to the surface of the adhesive portion 23a.

FIGS. 6A, 6B, 6C and 6D are as follows.
FIG. 5 is a side view showing a detailed structure of the adhesion preventing member 22, a plan view of one surface side, another side view, and a plan view of the other surface side. The adhesion preventing member 22 is formed of plastic or the like into a rectangular plate shape slightly smaller than the internal shape of the ink pack 21. Then, as shown in FIG. 6B, grooves 22a having a rectangular cross section are formed in a cross pattern on one surface side of the adhesion preventing member 22, and as shown in FIG. 6D, the adhesion preventing member 2 is formed.
On the other side of the second surface 2, a groove 22a having a rectangular cross section is formed in a cross shape.

FIGS. 7A and 7B are a side view and a plan view showing the disposition state of the ink pack 21 and the adhesion preventing member 22. The adhesion preventing member 22 is used for the ink pack 2
It is stored inside 1 in a free state. With such a configuration, since the ink pack 21 does not get caught in the adhesion preventing member 22 when the ink pack 21 expands or contracts due to the filling and consumption of the ink, it is possible to prevent the malfunction of the ink amount detecting means 23. Moreover, since the ink supplied from the main tank 10 flows into the ink pack 21 along the groove 22a, the ink pack 21 can be smoothly and initially filled.

FIGS. 8A and 8B are sectional views showing the operation of the ink amount detecting means 23. Ink amount detecting means 23
Switches 25a and 25b are arranged on both sides of the detection unit 23b in the direction of the arrow a in the figure, that is, on both sides in the direction in which the ink pack 21 expands and contracts in response to the fluctuation of the internal ink amount. The switch 25a is a detector 23b that is displaced when the ink pack 21 is completely contracted.
The switch is operated by being pressed by the button to detect that the ink amount in the ink pack 21 is in an Ink Low state, that is, the ink amount is in an almost empty state of, for example, 10 g or less.

The switch 25b is used for the ink pack 2
1 is a switch that is activated by being pushed by the detection unit 23b that is displaced when it fully expands, and the amount of ink in the ink pack 21 reaches the ink full (Ink F
It is adapted to detect that the ink is in a substantially full state of 20 g or more, for example. Then, the state in which the switches 25a and 25b are not operated, that is, the ink amount in the ink pack 21 is from the ink low state to the ink full state (InkFul).
l) It is set to be in normal use when it is in the state.

FIGS. 9A and 9B are a side view and a plan view showing another detailed structure of the ink pack. The ink pack 21 'includes the above-mentioned rectangular plate-like adhesion preventing member 22.
Is not provided, and the adhesion preventing member 2 having a semicircular convex cross section on one surface of the ink pack 21 to which the ink amount detecting means 23 is adhered.
2'is formed by, for example, press molding. In this way, since one surface of the ink pack 21 is deformed to form the adhesion preventing member 22 ', there is no need to prepare the above-mentioned rectangular plate-shaped adhesion preventing member 22 as a separate material, and
Since the adhesion preventing member 22 'can be formed at the same time when the ink pack 21' is formed, the sub-tank 20
The cost can be reduced.

As described above, the rectangular plate-shaped adhesion preventing member 2
As shown in FIG. 4, No. 2 is stored in the ink pack 21 in a free state, and the adhesion preventing member 22 'having a semicircular convex cross section has an ink amount as shown in FIGS. Since the adhesion part 23a of the detection means 23 and the one surface of the ink pack 21 'are formed so as to avoid the adhesion surface, neither the contact prevention members 22 nor 22' interfere with the detection part 23b of the ink amount detection means 23. . Therefore, the ink pack 22,
Since the amount of ink in 22 'can be constantly detected with high accuracy, it is possible to prevent printing failure due to insufficient ink supply.

With the above structure, as shown in FIG. 10, the main tank 10 (10B, 10Y, 10C,
10M), the connection port 10a has an ink transport pipe 42 (42
B, 42Y, 42C, 42M) and the sub-tank 20 (20B, 20Y, 20C, 20M) has an inlet 2
1a is connected to the ink transport pipe 42, and the outlet 21b is connected to the ink supply tube 44 (44B, 44Y, 44C, 44).
M).

A pressure detector 51 (51B, 51Y, 51C, 5) for detecting the pressure applied to the main tank 10.
1M), a solenoid valve 52 (52B, 52) for releasing pressure
Y, 52C, 52M), pressurizing pump 53, electromagnetic valve 4
3 (43B, 43Y, 43C, 43M), sub tank 2
The switches 25a and 25b and the suction pumps 45 and 47, which are activated by the displacement of the ink amount detection means 23 of 0, are electrically connected to the control device 50 and are connected to the main tank 10.
The amount of ink in the sub tank 20 and the inside of the sub tank 20 are checked, the suction pumps 45 and 47 and the pressurizing pump 53 are driven, and the opening and closing of the electromagnetic valves 43 and 52 are controlled. In addition, in FIG. 10, for convenience, the main tank 10, the sub tank 20, the pressurizing chamber 41, and the ink transport pipe 4 are illustrated.
2, the electromagnetic valve 43, the ink supply tube 44, etc. are not shown separately for each color ink, but only for one color.

An operation example of the initial filling in such a configuration will be described with reference to the flow charts of FIGS. 10 and 11 to 15. In the initial state, the electromagnetic valves 43 for all colors are closed. In addition, the subtanks 20 for all the colors contain air and the liquid to be delivered that enters during the assembly process. First, when the control device 50 receives an initial filling command from a host computer (not shown), the control device 50 discharges the air and the delivery liquid in each sub-tank 20 (step S1 in FIG. 11).

That is, the recording head 5 is moved to the non-printing area side and the recording head 5 is sealed by the capping device 46. Then, the suction pump 45 is operated to cause the negative pressure of the capping device 46 to act on each ink supply tube 44 and each sub-tank 20 via the recording head 5 to cap the air and the delivery liquid remaining in these members. It is discharged to the device 46.

The suction amount of the suction pump 45 at this time is not a fixed value, but is set to a variable value that varies depending on the ink amount in each sub tank 20. That is, it is determined whether or not the ink amount in each sub-tank 20 is, for example, 10 g or less in the Ink Low state (State A) (step S11 in FIG. 12). The suction amount is set to a small amount, for example, 1 g, and suction is performed until the state A is reached (step S1 in FIG. 12).
2). At this time, since the liquid to be delivered is contained in each sub-tank 20 instead of the ink, the determination is made based on the amount of the liquid to be delivered.

When the amount of liquid to be sent in each sub-tank 20 reaches the state A, the suction amount of the suction pump 45 is set to 1
A large amount of 00 g is set and suction is performed to bring each sub-tank 20 into a high negative pressure state, and each sub-tank 20 is crushed by the atmospheric pressure to completely discharge the air and the delivery liquid to the capping device 46 (step S13 in FIG. 12). ).

When the suction amount of the suction pump 45 is set to be considerably large, the suction amount may be set as a fixed value. Further, when the loop of steps S11 and S12 is repeated more than necessary due to a trouble, a threshold value of the number of loops is set in advance, and when the set number of times is exceeded, the process is forcibly proceeded to step S13. You may.

Next, the controller 50 controls each main tank 1
The ink in 0 is supplied to each sub tank 20 (step S2 in FIG. 11). That is, each electromagnetic valve 43 is opened to cause the ink in each main tank 10 to flow into each sub-tank 20 in the high negative pressure state (step S21 in FIG. 13). Then, it is determined whether or not the ink amount in each sub-tank 20 is in an Ink Low state (State A) to, for example, an ink full state (Ink Full) of 20 g or more (State C) (step S in FIG. 13).
22), if it is not in state A to state C (state B), for example, wait for 1 second (step S23 in FIG. 13).

As a result, the amount of ink in each sub-tank 20 gradually increases, and when the state B is reached, each electromagnetic valve 43
Is closed (step S24 in FIG. 13). It should be noted that in this embodiment, the pressurizing pump 53 operates to operate each main tank 1.
In a system that pressurizes 0 but does not pressurize each main tank 10, since each sub-tank 20 is in a high negative pressure state, this negative pressure primes each sub-tank 20 to transport each ink. The inside of the pipe 42 can be filled with ink, and each main tank 10 to each sub tank 2
Ink can be supplied to 0.

When the loop of steps S22 and S23 is repeated more than necessary due to a trouble, for example, a time which is considered to be sufficient for the ink amount in each sub tank 20 to reach the state B is set in advance. Alternatively, it may be set to forcibly advance to step S24 when the set time is exceeded. However, in this case, each main tank 1
Even if ink is not supplied from 0 to each sub-tank 20, the initial filling is continued. Therefore, in order to avoid it, for example, a fatal error (fault) or an ink end error (each The main tank 10 may be set so that there is no ink.

Here, for the ink supplied from each main tank 10 to each sub tank 20, each ink transport pipe 42 is used.
Since the air that was present inside is included, this air also needs to be discharged. Therefore, the control device 50 discharges the air and the ink in each sub tank 20 (step S3 in FIG. 11). That is, the suction pump 45 is operated to cause the negative pressure of the capping device 46 to act on each ink supply tube 44 and each sub-tank 20 via the recording head 5, and the air and ink in these members are discharged to the capping device 46. .

That is, it is determined whether the ink amount in each sub tank 20 is in the state A (step S in FIG. 12).
11) When not in the state A, the suction amount of the suction pump 45 is set to a small amount, for example, 1 g, and the suction is performed until the state A is reached (step S12 in FIG. 12). Then, when the amount of ink in each sub-tank 20 reaches the state A, the suction amount of the suction pump 45 is set to a large amount, for example, 100 g, and suction is performed to bring each sub-tank 20 into a high negative pressure state. Is crushed to completely discharge the air and ink to the capping device 46 (step S13 in FIG. 12).

Next, the controller 50 controls each main tank 1
The ink in 0 is supplied to each sub tank 20 (step S4 in FIG. 11). That is, each electromagnetic valve 43 is opened to cause the ink in each main tank 10 to flow into each sub-tank 20 in the high negative pressure state (step S21 in FIG. 13). Then, it is determined whether the ink amount in each sub-tank 20 is in the state B (step S in FIG. 13).
22), if it is not in the state B, for example, wait for 1 second (see FIG. 13).
Step S23).

When the amount of ink in each sub tank 20 reaches the state B, each electromagnetic valve 43 is closed (step S24 in FIG. 13). As a result, the air contained in the ink of each sub-tank 20 and contained in each ink transport pipe 42 can be completely discharged. Note that steps S3 and S4 may be repeated a plurality of times in order to more completely discharge the air contained in the ink in each sub-tank 20.

Here, if each electromagnetic valve 43 is opened when the inside of each sub-tank 20 is in a high negative pressure state, the ink rapidly flows from each main tank 10 into each sub-tank 20 and bubbles to cause degassing. There are cases. Therefore, the control device 50 discharges particularly bubbling ink, for example, 30% to 80%, and preferably 50% of the total amount of ink in the ink in each sub tank 20. That is, the suction pump 45 is operated to suck the ink in each sub-tank 20 and discharge it to the capping device 46 (step S5 in FIG. 11).

Next, the controller 50 controls each main tank 1
The ink in 0 is supplied to each sub tank 20 (step S6 in FIG. 11). That is, each electromagnetic valve 43 is opened to allow the ink in each main tank 10 to flow into each sub tank 20 (step S31 in FIG. 14). Then, it is judged whether or not the ink amount in each sub-tank 20 is in the state C (step S32 in FIG. 14), and if it is not in the state C, for example, wait for 1 second (step S33 in FIG. 14).

When the amount of ink in each sub tank 20 reaches the state C, each electromagnetic valve 43 is closed (step S34 in FIG. 14). It should be noted that in step S31 described above, since there is no negative pressure in each sub-tank 20, the problem of ink bubbling does not occur. As a result, the bubbling ink in each sub-tank 20 can be completely discharged, and the ink whose deaeration degree has been impaired can be diluted with the ink supplied until the state C is reached.

Here, in order to secure the print quality immediately after the initial filling, it is necessary to dissolve the air bubbles remaining in the stagnant portion of the flow in the recording head 5 into the ink, so that the ink with a high degree of degassing is used. Is required to flow to the recording head 5 by a constant amount.
Therefore, the control device 50 performs the initial filling of the recording head 5 (step S7 in FIG. 11). That is, the suction pump 4
5 is actuated to suck 50% of the total amount of ink in each sub-tank 20 and discharge it to the capping device 46 (step S41 in FIG. 15).

Then, the flushing operation of driving the recording head 5 to eject ink into the capping device 46 is performed (step S42 in FIG. 15). As a result, the fine air bubbles clinging around the actuator of the recording head 5 are separated and dissolved. In addition, at the time of flushing,
It is not necessary to seal the recording head 5 with the capping device 46, and the recording head 5 may be simply positioned on the capping device 46.

Next, the controller 50 supplies the ink in each main tank 10 to each sub-tank 20 in order to replenish the ink consumed by the initial filling of the recording head 5 (step S8 in FIG. 11). That is, each electromagnetic valve 43 is opened and each main tank 10 is connected to each sub tank 20.
The ink inside is made to flow in (step S31 in FIG. 14).
Then, it is determined whether the ink amount in each sub-tank 20 is in state C (step S32 in FIG. 14), and state C
If not, for example, wait for 1 second (step S3 in FIG. 14).
3). Then, the ink amount in each sub tank 20 is in the state C.
Then, the electromagnetic valves 43 are closed (step S34 in FIG. 14).

With the above, the initial filling process for each sub-tank 20 and the initial filling process for the recording head 5 are completed.
The steps S5 and S6 and the steps S7 and S8 may be performed as needed. Also,
In the above embodiment, the case where the present invention is applied to the ink jet printer 1 having one sub tank 20 for one main tank 10 has been described, but a plurality of sub tanks 20 (for one main tank 10 (described below) will be described. It can also be applied to an ink jet recording apparatus having a recording head 5).

FIG. 16 is a schematic diagram showing an ink jet recording apparatus having a plurality of sub tanks 20 (recording heads 5) for one main tank 10. The same components as those shown in FIG. 10 will be assigned the same reference numerals and explanations thereof will be omitted. This inkjet recording apparatus 100
Is a plurality of printers 101 having a sub tank 20,
It is provided with one main tank 10, a pressure detector 51 for detecting the pressure applied to the main tank 10, an electromagnetic valve 52 for releasing pressure, a pressurizing pump 53, and a system controller 55. The plurality of printers 101 are arranged with height differences.

Ink transport pipe 42 near each sub-tank 20
The electromagnetic valve 54 (54B, 54Y, 54C, 54
M) is provided. As a result, ink can be supplied from the main tank 10 only to the printer 101 that needs to supply ink to the sub tank 20. Further, each sub tank 20 is connected to the recording head 5 by an ink supply tube 44 via a damper 5c.

The system controller 55 controls the printer 101 a of each printer 101, the pressure detector 51, the electromagnetic valve 52 for releasing pressure, the pressurizing pump 53 and the electromagnetic valve 4.
3 is electrically connected to each of the printers 101 and the pressurizing pump 12, for checking the amount of ink in the main tank 10 and for controlling the opening and closing of the electromagnetic valves 43 and 52. Further, the control unit 101a of each printer 101 has a switch 25 that operates by the displacement of the electromagnetic valve 54 and the ink amount detection means 23 of the sub tank 20.
a, 25b electrically connected to the electromagnetic valve 54
It is designed to control opening and closing, check of ink remaining amount in the sub tank 20, and the like.

Note that, in FIG. 16, for convenience, the main tank 10, the sub tank 20, the pressurizing chamber 41, the ink transport pipe 42, the electromagnetic valve 43, the ink supply tube 44, and the like are not shown separately for each color ink. Actually, the main tank 10 and the sub-tank 20 are provided for each color and are connected to each other by the ink transport pipe 42 and the ink supply tube 44 for each color.

As described above, since the ink is supplied from one main tank 10 to the plurality of sub tanks 20,
One main tank 1 even with multiple printers 1
It is only necessary to replace 0, and work efficiency can be improved. In addition, the dynamic pressure in the ink transport pipe 42 between the main tank 10 and the sub tank 20 does not affect, and the recording head 5
Since only the dynamic pressure inside the ink supply tube 44 between the sub tank 20 and the sub tank 20 has an effect, the print quality is not deteriorated. Further, although the plurality of printers 1 are laid out with height differences, since the sub-tanks 20 are laid out so that the head difference between the sub-tank 20 corresponding to each printer 1 and the recording head 5 becomes constant, the sub-tank 20 It is possible to supply ink from the main tank 10 from
It is possible to secure print quality.

It should be noted that a plurality of main tanks 10 may be provided. In that case, when the remaining amount of ink in one main tank 10 becomes very small, it is possible to immediately switch to another main tank 10. While the main tank 10 is being used, it is possible to replace the main tank 10 in which the ink is running low with a new main tank 10 filled with ink.

Furthermore, even if a plurality of recording heads 5 are provided,
Static pressure, that is, a layout in the vertical direction with respect to the sub-tank 20, and a dynamic pressure, that is, a dynamic pressure generated in the ink supply tube 44 even if a plurality of recording heads 5 are printed at the same time, for example, a nozzle per head. Since there is no problem if the number of inks ejected per unit time or a small amount of time is satisfied, it is possible to increase the degree of freedom in design by a layout with a plurality of heads.

FIG. 17 is a diagram showing details of another form of the recording unit of the ink jet printer 1 of FIG. In addition,
The same components as those shown in FIG. 10 will be assigned the same reference numerals and explanations thereof will be omitted. The main tank 10 is provided with an ink remaining amount detection plate 11 on the surface thereof and has a pressure chamber 41 (41B,
1Y, 41C, 41M). Pressure chamber 41
Is a solenoid valve 48 (48) for adjusting the internal pressure arbitrarily.
B, 48Y, 48C, 48M) via suction pump 47
Of the discharge port 47b, and is connected to the atmosphere via the electromagnetic valve 49.

Then, the detector 12 for detecting the displacement of the ink remaining amount detecting plate 11 of the main tank 10 and the sub tank 20.
The switches 25a and 25b, the electromagnetic valves 43, 48 and 49, and the suction pumps 45 and 47, which are activated by the displacement of the ink amount detecting means 23, are electrically connected to the control device 50, and are arranged in the main tank 10. Each suction pump 4 such as checking the remaining amount of ink and the amount of ink in the sub tank 20
5, 47, etc., and each electromagnetic valve 43, 48, 49
It is designed to control the opening and closing of. In FIG. 10, for convenience, the main tank 10, the sub tank 20,
The pressurizing chamber 41, the ink transport tube 42, the electromagnetic valve 43, the ink supply tube 44, and the like are not shown for each ink of each color described above, but only for one color.

As described above, since the suction and the exhaust of the suction pump 47 are used to both fix the sheet and pressurize the main tank 10, the pressurizing pump 53 shown in FIGS. 10 and 16 is unnecessary. Therefore, the inkjet printer 1 can be downsized and the cost can be reduced.

In each of the above-described embodiments, the sub-tank 20 is described as having the adhesion preventing member 22, but the sub-tank without the adhesion preventing member 22 is also applicable. Further, in each of the above-described embodiments, the printer has been described as an example, but the present invention is not limited to this, and is applicable to a recording device having a sub tank, such as a facsimile device or a copying device.

[0063]

As described above, according to the ink filling method and the ink jet recording apparatus of the present invention, the flow path from the recording head to the opening / closing means via the sub ink tank by the first negative pressure action. The air in the flow path from the print head to the main ink tank can be discharged by the following negative pressure action. It is possible to eliminate the air present in the sub ink tank, improve the degassing degree of the ink filled in the sub ink tank, and improve the recording accuracy.

[Brief description of drawings]

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

FIG. 2 is a diagram showing details of a recording unit of the ink jet printer of FIG.

3 is a perspective view showing a detailed structure of a main tank of the ink jet printer of FIG.

4A and 4B are a plan view and a cross-sectional view taken along the line BB showing a detailed structure of a sub tank of the ink jet printer of FIG.

5 is a perspective view showing a detailed structure of an ink pack of the sub tank of FIG.

6 is a side view showing a detailed structure of a close contact prevention member of the sub tank of FIG. 4, a plan view of one surface side, another side view, and a plan view of the other surface side.

7A and 7B are a side view and a plan view showing an arrangement state of an ink pack of the sub-tank of FIG. 4 and the adhesion preventing member.

FIG. 8 is a cross-sectional view showing the operation of the ink amount detection means of the sub tank of FIG.

9A and 9B are a side view and a plan view showing another detailed structure of the ink pack of the sub tank of FIG.

10 is a diagram showing details of a recording unit of the ink jet printer of FIG.

11 is a flowchart showing an operation example of initial filling of the ink jet printer of FIG.

12 is a first flowchart showing a detailed operation example of FIG.

FIG. 13 is a second flowchart showing a detailed operation example of FIG. 11.

14 is a third flowchart showing a detailed operation example of FIG. 11. FIG.

15 is a fourth flowchart showing a detailed operation example of FIG.

FIG. 16 is a schematic configuration diagram showing an inkjet recording apparatus having a plurality of sub-tanks (recording heads) for one main tank to which the present invention is applicable.

FIG. 17 is a diagram showing details of another form of the recording unit of the ink jet printer of FIG. 1.

[Explanation of symbols]

1 Inkjet printer 2 frames 3 windows 4 carriage 5 recording head 6 Paper guide member 7 Operation panel 8 covers 9 Main tank storage 10 main tank 11 Ink remaining amount detection plate 20 sub tanks 21, 21 'ink pack 22, 22 'Adhesion prevention member 22a groove 23 Ink amount detecting means 23a adhesive part 23b detector 24 fixed plate 25a, 25b switch 41 Pressurization chamber 42 Ink transport pipe 43, 48, 54 Electromagnetic valve 44 ink supply tube 45, 47 suction pump 46 capping device 50 controller 51 Pressure detector 49, 52 solenoid valve for pressure relief 53 Pressurizing pump 55 System control unit 100 inkjet recording device 101 printer

   ─────────────────────────────────────────────────── ─── Continued front page    F-term (reference) 2C056 EA26 EB50 EC18 EC19 EC20                       EC32 FC02 JA03 JA13 KA08                       KB05 KB08 KB37 KC02 KC10                       KC14 KC18

Claims (9)

[Claims] 1. A main ink tank, which is connected to a pipe, for storing ink, an opening / closing means for opening / closing the pipe, a sub ink tank for temporarily storing the ink, and an ink drop. A method for initially filling the sub-ink tank with the ink from the main ink tank, comprising a recording head, wherein the opening / closing means is closed to apply a negative pressure to the recording head, The tank is crushed at atmospheric pressure to discharge the air in the sub ink tank, the opening / closing means is opened to allow the ink to flow from the main ink tank to the sub ink tank, and the opening / closing means is closed. A negative pressure is applied to the recording head to crush the sub ink tank at atmospheric pressure to discharge ink and air in the sub ink tank, The ink filling method wherein the open stage filled with the ink allowed to flow into the ink tank of the sub from the ink tank of the main. 2. After the stroke according to claim 1, the opening / closing unit is closed to suck and discharge a predetermined amount of ink in the ink in the sub ink tank, and the opening / closing unit is opened to open the main unit. The ink filling method, wherein the ink is caused to flow from the ink tank to the sub ink tank to be filled. 3. After completion of the stroke according to claim 1 or 2, the opening / closing means is closed to suck ink in the sub ink tank to pass the flow path between the sub ink tank and the recording head. And an ink filling method, wherein the ink is filled into the recording head by flowing. 4. A main ink tank, which is connected to a pipe and stores ink, an opening / closing means for opening and closing the pipe, a sub ink tank for temporarily storing the ink, and an ink drop. A method for initially filling the sub-ink tank with the ink from the main ink tank, comprising a recording head, wherein the opening / closing means is closed to apply a negative pressure to the recording head, The tank is crushed at atmospheric pressure to discharge the air in the sub ink tank, the opening / closing means is opened to allow the ink to flow from the main ink tank to the sub ink tank, and the opening / closing means is closed. Suctioning the ink in the sub ink tank and injecting it into the flow path between the sub ink tank and the recording head and the recording head to fill the ink. An ink filling method characterized by: 5. The opening / closing means is closed to apply a negative pressure to the recording head, and the sub-ink tank is crushed by the atmospheric pressure to discharge ink and air in the sub-ink tank. 2. A series of steps for opening and opening and filling the sub ink tank with the ink from the main ink tank are performed a plurality of times.
4. The ink filling method according to any one of 3 above. 6. The ink filling according to claim 1, wherein the main ink tank is arranged below the sub ink tank and is pressurized. Method. 7. The ink filling method according to claim 1, wherein the main ink tank is arranged above the sub ink tank. 8. The sub ink tank is made of a flexible material, and is provided with an adhesion preventing member for preventing adhesion of the flexible materials to each other. The ink filling method according to any one of claims. 9. An ink jet recording apparatus using the ink filling method according to claim 1. Description: