JP3584776B2 - Ink jet recording device - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an ink jet recording apparatus which is mounted on a carriage together with a recording head and includes a sub-tank for supplying ink to the recording head, and configured to supply ink from the main ink tank to the sub-tank via an ink supply path. Equipment related.
[0002]
[Prior art]
2. Description of the Related Art Ink jet recording apparatuses have been used in many types of printing including color printing in recent years because noise during printing is relatively small and small dots can be formed with 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 a paper feeding unit for moving the recording paper relatively to the recording head, Recording is performed by ejecting ink droplets onto the recording paper while moving the recording head in the width direction of the recording paper on the carriage.
[0003]
On a common carriage, for example, a black recording head that ejects black ink, and a color recording head that can eject yellow, cyan, and magenta inks are mounted. By changing the ink ejection ratio, full-color printing is possible.
[0004]
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 ink tank is loaded into a mounting apparatus (cartridge holder) arranged, for example, on a side of an apparatus body. Then, a sub-tank is arranged on a carriage on which the recording head is mounted, ink is supplied from the main ink tank to each sub-tank via an ink supply tube, and ink is further supplied from each sub-tank to the recording head. It is configured to supply.
[0005]
[Problems to be solved by the invention]
By the way, in the recording apparatus as described above, an ink supply tube is connected corresponding to each ink in order to supply ink from each main ink tank to each subtank. In a recording apparatus having a long scanning distance for performing printing on the paper surface, there is a problem that the ink supply tube gives resistance to the movement of the carriage.
[0006]
Therefore, when the remaining amount of ink in the sub tank is low, the carriage moves to the ink supply stage, and a recording device that supplies ink from each main ink tank to each sub tank via a connection mechanism at the corresponding position is provided. It has been proposed by the applicant. In this case, it is desired that each sub-tank be filled with an appropriate amount of ink so that the amount is substantially equal. In addition, in order to improve the throughput, the ink filling operation is performed in a short time. It is desirable to have a configuration that can be completed.
[0007]
The present invention has been made based on such a technical demand, and when supplying ink from an ink cartridge to each sub-tank, an air valve communicating with a pressure reducing pump as a negative pressure generating means is opened. It is an object of the present invention to provide a recording apparatus provided with a decompression control unit that puts the inside of a sub tank in a decompression state by setting the valve state.
[0008]
[Means for Solving the Problems]
In order to achieve the above object, an ink jet recording apparatus according to the present invention has a recording head mounted on a carriage and reciprocally driven in the width direction of recording paper, and a main ink mounted on the carriage together with the recording head. An ink jet recording apparatus comprising: a sub-tank receiving ink supply from a tank via an ink supply path and supplying ink to the recording head, wherein the ink is stored in the sub-tank and stored in the sub-tank. A floating member that floats up, and when the ink in the sub-tank becomes equal to or less than a predetermined value, the air valve communicating with the negative pressure generating means is opened by the movement of the float member to introduce ink into the sub-tank; When a certain amount of ink is filled in the float member, Pressure reduction control means for stopping the supply of ink of the air valve to the sub-tank as closed communicating with the negative pressure generator by dynamic A valve member provided with a valve opening communicating with the negative pressure generating means, and a seal member disposed on the float member to close or open the valve opening with movement of the float member. The valve member has a trapezoidal cross section in the vertical direction, and a valve opening communicating with the negative pressure generating means is formed in the center in the vertical direction, and the short side of the trapezoidal cross section is formed. In the above, the seal member is configured to abut, and the valve member is formed with a flexible thin film at a short side portion having a trapezoidal cross section. .
[0009]
In this case, it is preferable that the pressure reduction control means is configured to communicate with one negative pressure generation means via each air valve provided in a sub tank storing each ink. In this case, it is preferable that the ink outlet of the main ink tank is configured to be lower in the direction of gravity with respect to the ink supply port arranged in the sub-tank, or to have a negative pressure at the ink supply port. .
[0010]
In a preferred embodiment, the float member is arranged so as to be movable up and down in the direction of gravity about a support shaft arranged in the sub-tank. Further, the float member is preferably formed by one side surface and a peripheral side surface integrally formed with the one side surface, and is joined to a box-shaped member having an open portion on the other surface side, and an open portion of the box-shaped member. And a plate-shaped lid that closes.
[0011]
In a preferred embodiment, the float member has a quadrangular volume formed at a position separated from the support shaft when viewed in the horizontal direction, and the quadrangular volume near the support shaft. And a three-sided volume having a bottom surface substantially linearly formed on the side of the support shaft from the bottom surface of the support member.The distance between the center of rotation of the support shaft and the center of gravity of buoyancy by the float member is increased. You.
[0012]
Preferably, the float member has at least a pair of positioning pins projecting horizontally on both outer sides thereof to maintain a predetermined distance between the float member and the inner wall of the sub tank. In this case, it is desirable that the positioning pin is formed so as to maintain a distance of at least 1 mm or more between the float member and the inner wall of the sub tank.
[0013]
On the other hand, the air valve includes a valve member having a valve opening communicating with the negative pressure generating means, and a seal member disposed on the float member and closing or opening the valve opening with the movement of the float member. In this case, the valve member constituting the air valve is preferably formed of a soft material, and the seal member is formed of a hard material. As the valve member constituting the air valve, a member formed of a soft elastomer can be used.
[0014]
Further, it is desirable that the seal member constituting the air valve is disposed at an intermediate point between the buoyancy center of gravity of the float member and the support shaft, and the valve member has a trapezoidal vertical cross-sectional shape, and It is preferable that a valve opening communicating with the negative pressure generating means is formed in a central portion thereof in a vertical direction, and that a sealing member abuts on a short side portion having a trapezoidal cross section. It is also possible to suitably employ a valve in which a valve opening communicating with the negative pressure generating means is formed to have a triangular cross section at the long side of the trapezoidal cross section. Further, the valve member may suitably adopt a shape in which a flexible thin film is formed at a short side portion of a trapezoidal cross section.
[0015]
Further, it is preferable that the valve member is formed integrally with the inner peripheral surface of the annular fixing member, and the valve member is attached to the sub-tank via the fixing member. It is also preferable that the mounting portion and the mounting portion of the valve member are formed on the same molded member. Then, a configuration in which a cylindrical ink adhesion preventing rib is integrally formed on the molded member to which the valve member is attached so as to surround the valve member can also be suitably adopted.
[0016]
Further, in the sub-tank provided with each of the above-described configurations, when the buoyancy of the float member is maximized by filling the sub-tank with ink, the end surface of the valve member and the end surface of the seal member are substantially parallel to each other. It is preferable to be configured to abut in a state.
[0017]
Further, as the air valve, a flexible thin film body that forms a space portion by communicating with a negative pressure generating means, and a fixed amount of ink that is formed in a part of the flexible thin film body and fills a sub tank. An opening that is closed by a seal member disposed on the float member when the opening is closed, and the flexible thin film body contracted by closing the opening by the seal member allows the negative pressure generating means to be closed. A configuration in which the communication portion is sealed may be employed.
[0018]
According to the above configuration, when the ink in 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 unit is lowered, and the air valve communicating with the decompression pump as the negative pressure generation unit Is opened. As a result, the inside of the sub-tank is depressurized by the action of the decompression pump. Therefore, the sub-tank receives the negative pressure and the ink is supplied more quickly than the main ink tank.
[0019]
Then, when the ink is filled up to a predetermined liquid level in each sub-tank, the air valves arranged in the respective sub-tanks are closed to release the reduced pressure state. Thus, the supply of the ink to the sub tank is stopped in an appropriate filling state.
[0020]
In this case, as described above, the pressure reduction control means is configured to be communicated with one negative pressure generation means via the respective air valves provided in the sub tanks storing the respective inks. On the other hand, ink can be filled while applying a common negative pressure. Then, the air valves are sequentially closed in accordance with the remaining amount of ink in each sub-tank, and the filling of each of the inks is completed.
[0021]
BEST MODE FOR CARRYING OUT THE INVENTION
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 sectional view showing an example of a sub tank in an ink jet recording apparatus to which the present invention is applied. The sub-tank 1 is mounted on a carriage together with a connection mechanism 2 mounted thereon and a recording head described later, and is configured to be reciprocated in the width direction of recording paper (not shown). Then, it is configured such that ink can be supplied from the main ink tank via the connection mechanism 2 and ink can be supplied to the recording head.
[0022]
The sub-tank 1 includes a case 1a and a lid 1b that closes an upper part of the case 1a, thereby forming an ink storage chamber 1c whose inside is sealed. In the sub-tank 1, there is arranged a float member 3 which floats by the ink stored in the sub-tank. As will be described later in detail, the float member 3 is configured to be movable up and down in the direction of gravity with a support shaft 4 disposed horizontally in the sub tank 1 as a center of rotation.
[0023]
A seal member 5 is disposed above the float member 3. The seal member 5 floats with the ink filled in the sub tank 1 to form an air valve disposed above the sub tank 1. By contacting the valve member 6, a suction passage leading to a pressure reducing pump as a negative pressure generating means described later can be closed.
[0024]
The sub tank 1 is provided with an ink supply port 7 for receiving ink from a main ink tank, which will be described later, via the connection mechanism 2. The sub tank 1 has a recording head, which will be described later, via the connection mechanism 2. There is also provided an ink supply port 8 for supplying ink to the printer. Further, an air inlet 9 is arranged above the sub-tank 1 so that air can be introduced from the air inlet 9 in response to consumption of ink during printing.
[0025]
Although FIG. 1 shows the configuration of one sub-tank, a plurality of sub-tanks having the same configuration are provided in the vertical direction on the paper in correspondence with each ink to be handled.
[0026]
On the other hand, the connection mechanism 2 is provided with a common valve member 11 connected to the decompression pump via a suction space (hereinafter also referred to as a suction port) 10 communicating with the valve member 6. The suction space 10 is formed in a direction perpendicular to the paper surface so as to be transversely communicated with each of the sub-tanks, so that the suction space 10 is disposed on the ink supply stage via a common valve member 11. It is configured so that it can be connected to another connection mechanism (not shown). The valve member 11 is configured to open when it is connected to another connection mechanism arranged on the ink supply stage.
[0027]
A replenishing space 12 for feeding ink to the ink replenishing port 7 is formed in the connection mechanism 2 so as to correspond to each sub-tank 1, and via a valve member 13 arranged in each replenishing space 12. Thus, it is configured to be connectable to another connection mechanism (not shown) arranged on the ink supply stage. Note that each of the valve members 13 is also configured to open when connected to another connection mechanism arranged on the ink supply stage.
[0028]
In the connection mechanism 2, in an ink supply path from the ink supply port 8 to the recording head, ink supply valves 14 that are controlled to open and close are individually arranged corresponding to the respective sub-tanks. Further, in the connection mechanism 2, air introduction valves 15 which are opened and closed opposite to the above-mentioned air introduction ports 9 are individually arranged corresponding to the respective sub-tanks, and the air introduced through the air introduction valves 15 is provided. The introduction space 16 is formed so as to communicate transversely and is not shown in FIG. 1, but a part of the air introduction space 16 is open to the atmosphere.
[0029]
Between the sub-tank 1 and the connection mechanism 2, for example, as shown by the configuration of the ink supply port 8, a pipe 17 integrally extending from the sub-tank 1 side is formed in a concave portion 18 formed on the connection mechanism 2 side. It is connected so as to be press-fitted into the packing 19 arranged. This configuration is similarly applied to the ink supply port 7, the valve member 6, and the air introduction port 9 described above.
[0030]
In the embodiment shown in FIG. 1, a projection 20 protruding from one side wall of the sub tank 1 enters an engagement hole 21 formed in the connection mechanism 2 and is formed on the other side wall of the sub tank 1. The two are integrally connected to each other so that the engaging claw 23 formed on the connection mechanism 2 gets over the protrusion 22.
[0031]
FIG. 2 is a schematic diagram showing a basic configuration of one ink supply system that supplies ink from a ink cartridge serving as a main ink tank to a recording head via the above-described sub-tank. Note that, in each of the drawings after FIG. 2 described below, the portions corresponding to FIG. 1 are denoted by the same reference numerals, and accordingly, the description thereof will be appropriately omitted. Similarly, in each of the drawings after FIG. 2, the connection mechanism 2 shown in FIG. 1 and the connection mechanism on the ink supply stage side connected to this connection mechanism are omitted.
[0032]
Reference numeral 31 in FIG. 2 indicates a main ink tank, and this main ink tank 31 is loaded into, for example, a cartridge holder arranged on both outer sides of the recording apparatus. The ink is supplied to the sub-tank 1 mounted on the carriage via the ink supply path 32. Also, as shown in FIG. 1, the sub tank 1 is configured to supply ink to the recording head 33 via the ink supply valve 14. Furthermore, the sub-tank 1 is connected to a pressure reducing pump 35 as a negative pressure generating means via a common suction path 34 communicating with the valve member 6 disposed inside.
[0033]
As schematically shown in FIG. 2, in this configuration, the ink lead-out section 31a of the main ink tank 31 is positioned lower in the direction of gravity with respect to the ink supply port 7 arranged in the sub-tank, in other words, Both are arranged so that the supply port 7 has a negative pressure. With such a configuration, it is possible to prevent the leakage of the ink in the connection mechanism arranged on the ink supply stage.
[0034]
3 to 6 show the amount of ink stored in the sub-tank 1, the operation of the float member 3, and the joining relationship between the seal member 5 and the valve member 6 associated with the operation of the float member 3. FIG. 3 to 6, the description of the main ink tank 31 and the recording head 33 is omitted.
[0035]
First, FIG. 3 shows an ink end state in which the ink supply valve 14 is controlled to the open state, and the ink stored in the sub tank 1 is supplied to the recording head 33 side, so that the ink amount in the sub tank 1 is reduced. ing. In this state, the float member 3 is set down via the shaft 4. Although not shown in FIG. 3, in this state, the air introduction valve 15 shown in FIG. 1 is open.
[0036]
Next, FIG. 4 shows a state in which replenishment of ink into the sub tank 1 has been started. In this state, the sub tank 1 moves to the ink supply stage, the ink supply path 32 is connected to the ink supply port 7 via the connection mechanism 2, and the suction port of the valve member 6 34. In this state, the ink supply valve 14 extending from the sub tank 1 to the recording head 33 is closed, and the air introduction valve 15 is also closed.
[0037]
In the state shown in FIG. 4, since the seal member 5 arranged on the float member 3 is separated from the valve member 6, the inside of the sub tank 1 is reduced in pressure by the operation of the pressure reducing pump 35. Accordingly, ink is supplied from the main ink tank 31 to the sub tank 7 via the ink supply path 32.
[0038]
FIG. 5 shows a state in which ink is supplied from the main ink tank 31 into the sub tank 1 and the ink in the sub tank 1 is almost full. In this state, the float member 3 floats with the ink, and accordingly, the seal member 5 contacts the valve member 6 to close the air valve. At this time, the seal member 5 is sucked by the decompression pump 35 and comes into close contact with the valve member 6, and the decompression in the sub tank 1 is stopped. Therefore, replenishment of ink from the main ink tank 31 into the sub tank 1 is also stopped.
[0039]
Then, when all the sub-tanks are filled with ink, the connection mechanism arranged on the ink supply stage and the connection mechanism 2 arranged on the sub-tanks are released as shown in FIG. In this state, the ink supply valve 14 from the sub tank 1 to the recording head 33 is opened, and the air introduction valve 15 is also opened, and printing by the recording head 33 is started.
[0040]
7 and 8 show the configuration of the float member 3, wherein FIG. 7 is a side view and FIG. 8 is an exploded perspective view. The float member 3 has a box-shaped member 3c having a peripheral side surface 3b integrally formed on one side surface 3a and an open side on the other side, and a plate-shaped member joined to an open portion of the box-shaped member 3c and closed. 3d. With this configuration, molding with a synthetic resin can be facilitated, and the apparent specific gravity can be reduced.
[0041]
The float member 3 has positioning pins 3e to 3h formed on both outer sides thereof so as to protrude horizontally. The positioning pins 3e and 3f are arranged on the free end side of the float member 3 with respect to the support shaft 4 from the same location toward both outsides, and the positioning pins 3g and 3h are positioned on the support shaft 4 side of the float member 3. It is arranged from both sides from the same location.
[0042]
It is desirable that these pins 3e to 3h protrude from the side surfaces of the float member 3 by 1 mm or more, thereby acting to maintain a distance of at least 1 mm between the float member and the inner wall of the sub tank. This can solve the problem that the surface tension of the ink acts between the float member and the inner wall of the sub-tank to hinder the movement of the float member.
[0043]
Next, FIG. 9 is an enlarged view of the configuration of the above-described valve member 6, in which (A) is a perspective view and (B) is a central sectional view. FIG. 10 shows another embodiment of the valve member 6, and FIG. 11 shows another embodiment of the valve member 6 in a central sectional view. The valve member 6 shown in each of the above-described drawings is formed of a soft material, for example, a soft elastomer, and is configured to achieve close contact with the seal member 5 by the hard material disposed on the float member 3. Have been. The valve member 6 is integrally formed on the inner peripheral surface of the annular fixing member 41, and is attached to the sub tank 1 via the fixing member 41. The fixing member 41 may be a soft material.
[0044]
As shown in FIG. 9B, the valve member 6 according to the first embodiment has a trapezoidal cross section in the vertical direction, and a valve opening 6a is formed in the center in the vertical direction. At the same time, the seal member 5 is configured to abut on an end face of a short side portion having a trapezoidal cross section. With this configuration, the contact position of the seal member 5 made of a hard material can be made constant, and the sealing (valve closing) operation between the two can be reliably performed by the slight buoyancy of the float member 3. be able to.
[0045]
Further, as shown in FIG. 10, the valve member 6 according to the second embodiment is configured such that the valve opening 6a is expanded in a triangular cross section at the long side of the trapezoidal cross section. According to this configuration, the valve member 6 can further provide mechanical flexibility in addition to the flexibility of its material, and can obtain good sealing characteristics.
[0046]
Further, the valve member 6 according to the third embodiment has a configuration in which a flexible thin film member 6b is formed in a circumferential direction on a short side portion having a trapezoidal cross section as shown in FIG. According to this configuration, the valve member 6 can increase the seal area without increasing the load required for the seal, and can also seal with the seal member 5 by the depressurizing force of the depressurizing pump 35. More stable and good sealing characteristics can be obtained.
[0047]
Next, FIGS. 12A and 12B are enlarged views of the configuration of the lid 1b constituting the sub tank 1. FIG. 12A is a central sectional view, and FIG. 12B is a bottom view. The lid 1b is formed with a pair of mounting portions 1d for supporting the support shaft 4 of the float member 3 described above, and the mounting portion 1e of the valve member 6 is formed of the same molded member, that is, the lid. It is formed on the body 1b. As a result, the valve member 6 and the float member 3 are attached to the same lid, so that variations during assembly can be suppressed, and stable sealing characteristics can be obtained.
[0048]
Further, the lid 1b is formed with a tubular ink adhesion preventing rib 1f so as to surround the mounting portion 1e of the valve member 6, so that the ink is inserted into the valve opening 6a of the valve member 6 mounted on the mounting portion 1e. Is configured to be able to prevent the air valve from adhering, thereby ensuring the reliability of the operation of the air valve.
[0049]
On the other hand, FIG. 13 shows an ideal shape of the float member 3, and FIG. 13A shows a float member having the same shape as that shown in FIGS. 1 to 8, and FIGS. (C) shows the shape of the float member to be compared with this. That is, the shape shown in (B) shows an example in which the float portion is formed in a vertically long state, and the shape shown in (C) shows an example in which the float portion is formed in a horizontally long state. The portion indicated by reference numeral 3j indicates the buoyancy center of gravity of each float member, and the vertical width indicated by reference numeral 3k of each float member increases the buoyancy when the ink level rises by 1 mm. Indicates the amount.
[0050]
As shown in FIG. 13, when comparing the distance between the support shaft 4 and each buoyancy center of gravity 3j, Lb>La> Lc. Further, according to the shape shown in FIG. 3B, the distance Lb between the support shaft 4 and the buoyancy center 3j can be increased, so that when the ink is supplied and the buoyancy acts, the contact force of the seal member 5 on the valve member 6 is exerted. Is increased, and the sealing property between the two is improved. However, when the ink level rises by 1 mm, the degree of increase in buoyancy (vertical width indicated by reference numeral 3k) is small, and there is a problem that the ink level varies when replenishment is stopped.
[0051]
Further, according to the shape shown in (C), since the distance Lc between the support shaft 4 and the buoyancy center 3j is short, the contact force of the seal member 5 to the valve member 6 when the buoyancy works by supplying ink is small. It becomes smaller as compared with (A) and (B). However, the shape shown in (C) has a characteristic that the buoyancy increases when the ink level rises by 1 mm, so that the variation in the ink level when the ink supply is stopped can be suppressed to a small level. I have. Therefore, the shape shown in (A) which makes use of both the characteristics shown in (B) and (C) above is preferable.
[0052]
FIG. 14 shows a preferred arrangement when the float member 3 having the shape shown in FIG. 13A is used. That is, the float member 3 has a quadrangular volume 3m formed at a position separated from the support shaft 4 when viewed from the horizontal direction, and a bottom surface of the quadrangular volume near the support shaft 4. A three-sided volume 3n having a substantially linear bottom surface on the support shaft side. Thereby, the distance between the center of rotation of the support shaft 4 and the center of gravity of buoyancy 3j by the float member is made relatively large, and the amount of increase in buoyancy due to the rise in the ink level is made relatively large. Have been.
[0053]
The seal member 5 is disposed at an intermediate point between the buoyancy center of gravity 3j of the float member 3 and the support shaft 4, so that the contact force of the seal member 5 against the valve member 6 due to the buoyancy generated in the float member 3 is increased. It is configured.
[0054]
Further, according to the configuration shown in FIG. 14, when the liquid level of the ink reaches a height that covers the entire float member 3, the buoyancy of the float member 3 becomes maximum, and accordingly, the sealing member 5 contacts the valve member 6 with the buoyancy. When the contact force is maximized, the valve member 6 comes into contact with the seal member 5 with the deformation amount g.
[0055]
Here, when the upper surface of the sealing member 5, that is, when the sealing surface is horizontal without tilting, the sealing performance is best, when the upper surface of the float member 3 is horizontal, the valve member 6 are preferably set so as to overlap by the dimension g.
[0056]
Next, FIGS. 15 to 17 show another embodiment of the air valve portion communicating with the pressure reducing pump in order of operation. In this configuration, a flexible thin film member 52 which forms a space portion 51 in communication with the pressure reducing pump 35 side is disposed in the sub tank 1, and a part of the thin film member 52 is disposed on the float member 3. An opening member 53 closed by the closed seal member 5 is provided.
[0057]
Further, a first suction surface 54 with which the opening member 53 contacts is formed in the space 51 formed by the thin film member 52. In addition, the communication port 10 that has a trapezoidal vertical cross-section and is formed perpendicularly to the center of the communication port 10 and communicates with the decompression pump 35, and the thin film member 52 adheres closely to the short side of the trapezoidal cross-section Is also formed.
[0058]
As can be understood in the course of the operation shown in FIGS. 15 and 16, as the supply of ink into the sub-tank 1 progresses, the seal member 5 approaches the opening member 53. Then, when the ink is further filled, as shown in FIG. 16, the sealing member 5 causes the opening member 53 to abut on the first suction surface 54 while deforming the thin film member 52. Then, even if the opening member 53 and the first suction surface 54 are not completely sealed, the space 51 is depressurized by the operation of the decompression pump 35. Therefore, as shown in FIG. 17, the thin film 52 is immediately sucked into the space 51 side, and at the same time, the thin film 52 closes the second suction surface 55.
[0059]
By the above operation, the communication port 10 to the pressure reducing pump is sealed, the pressure reduction in the sub tank 1 is stopped, and the supply of ink is stopped. Therefore, according to the configuration shown in FIGS. 15 to 17, the load required to seal the communication port 10 may be a load sufficient to deform the flexible thin film member 52. Can be reduced, in other words, the float member 3 can be reduced. Further, since the flexible thin film 52 acts to seal the communication port to the pressure reducing pump, the valve closing action can be ensured.
[0060]
【The invention's effect】
As is apparent from the above description, according to the ink jet recording apparatus of the present invention, the float member floating by the ink stored in the sub tank and the air valve communicating with the negative pressure generating means by the movement of the float member are opened. Since the decompression control means for controlling the air pressure in the sub-tank in the valve or valve closed state is disposed, it is possible to quickly fill the sub-tank in the decompressed state with ink, thereby improving the throughput of the recording apparatus. Further, when the sub tank is filled with ink up to a predetermined liquid level, the ink filling operation can be reliably stopped by the action of the air valve, and the reliability of the ink supply operation can be improved. It becomes possible.
[0061]
In addition, by being configured to communicate with one negative pressure generating means via each air valve provided in the sub-tank storing each ink, the air is sequentially aired according to the residual amount of the ink in each sub-tank. Since the valves are closed and the filling of the ink with respect to each of them can be completed, the filling step of the ink can be efficiently executed.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view illustrating a configuration of a sub tank and a connection mechanism in an ink jet recording apparatus to which the present invention is applied.
FIG. 2 is a schematic diagram illustrating a configuration of an ink supply system from a main ink tank to a recording head.
FIG. 3 is a sectional view showing a state of an ink end in a sub tank interposed in the ink supply system shown in FIG. 2;
FIG. 4 is a cross-sectional view showing a state where ink is supplied to a sub tank.
FIG. 5 is a cross-sectional view showing a state in which the ink in the sub tank is full.
FIG. 6 is a cross-sectional view of the sub-tank showing a state where printing is started.
FIG. 7 is a side view showing a configuration of a float member housed in a sub tank.
FIG. 8 is an exploded perspective view showing the configuration of the float member.
FIG. 9 is an external view and a sectional view showing a first embodiment of the valve member mounted on the sub tank.
FIG. 10 is a cross-sectional view showing a second embodiment of the valve member.
FIG. 11 is a sectional view showing a third embodiment of the valve member.
FIG. 12 is an enlarged view showing a configuration of a lid constituting a sub tank.
FIG. 13 is a side view comparing the characteristics of each float member.
FIG. 14 is a cross-sectional view showing a preferred arrangement relationship of a float member in a sub tank.
FIG. 15 is a partial sectional view showing another embodiment of the air valve communicating with the negative pressure generating means.
FIG. 16 is a partial sectional view showing the operation of the air valve shown in FIG. 15;
FIG. 17 is a partial sectional view showing a state where the air valve shown in FIG. 15 is closed.
[Explanation of symbols]
1 sub tank
1b Subtank lid
1f Ink adhesion prevention rib
2 Connection mechanism
3 Float member
3f Positioning pin
3g positioning pin
3h positioning pin
4 Support shaft
5 Seal members
6. Valve member (air valve)
6a Valve opening
7 Ink supply port
8 Ink supply port
9 Air inlet
10 Suction space (suction port)
14 Ink supply valve
15 Air introduction valve
31 Main ink tank
31a Ink lead-out section
32 Ink supply path
33 Recording Head
34 Suction path
35 Pressure reducing pump (negative pressure generating means)
41 Valve fixing member
51 Space
52 Flexible thin film
53 Opening member
54 First suction surface
55 Second suction surface

Claims (10)

A recording head mounted on a carriage and reciprocally driven in the width direction of the recording paper; and a recording head mounted on the carriage together with the recording head, receiving ink from a main ink tank via an ink supply path, and supplying ink to the recording head. An ink jet recording apparatus comprising:
A float member housed in the sub-tank and floated by the ink stored in the sub-tank, and an air valve communicating with the negative pressure generating means by movement of the float member when the ink in the sub-tank becomes equal to or less than a predetermined value. Is opened to introduce ink into the sub-tank, and when the sub-tank is filled with a certain amount of ink, the air valve communicating with the negative pressure generating means by the movement of the float member is closed to set the air valve in the sub-tank. Having a pressure reduction control means for stopping the supply of ink to the
The air valve is constituted by a valve member having a valve opening communicating with the negative pressure generating means, and a seal member disposed on the float member to close or open the valve opening with the movement of the float member,
The valve member has a trapezoidal cross section in a vertical direction, and a valve opening communicating with the negative pressure generating means is formed in a central portion in a vertical direction, and the seal is formed at a short side of the trapezoidal cross section. The members are configured to abut,
An ink jet recording apparatus , wherein a flexible thin film is formed on a short side of the trapezoidal cross section of the valve member . 2. The ink jet recording apparatus according to claim 1, wherein the pressure reduction control unit is configured to communicate with one negative pressure generation unit via respective air valves provided in a sub tank storing each ink. 3. The ink outlet of the main ink tank is configured to have a lower position in the direction of gravity with respect to the ink supply port disposed in the sub tank, or to have a negative pressure at the ink supply port. 3. The ink jet recording apparatus according to 2. 4. The ink jet recording apparatus according to claim 1, wherein the float member is arranged so as to be movable up and down in a direction of gravity about a support shaft arranged in a subtank as a rotation center. 5. The float member is formed by one side surface and a peripheral side surface formed integrally with the one side surface, a box-shaped member having an open portion on the other surface, and a plate that is joined to the open portion of the box-shaped member and closed. The ink jet recording apparatus according to any one of claims 1 to 4, wherein the ink jet recording apparatus is constituted by a lid having a shape of a circle. The float member has a volume on four sides formed at a position separated from the support shaft when viewed in the horizontal direction, and a substantially straight line from the bottom surface of the quadrilateral volume to the support shaft side near the support shaft. 6. A three-sided volume body having a bottom surface formed in a shape, wherein the distance between the center of rotation of the support shaft and the center of gravity of buoyancy by the float member is increased. Inkjet recording device. The at least one pair of positioning pins, which protrude horizontally on both outer sides of the float member and maintain a predetermined distance between the float member and the inner wall of the sub-tank, are formed. 7. The ink jet recording apparatus according to any one of 6. 2. The ink jet recording apparatus according to claim 1 , wherein a seal member forming the air valve is disposed at an intermediate point between a buoyancy center of gravity of the float member and the support shaft. 3. 9. The ink jet recording apparatus according to claim 7 , wherein the mounting of the support shaft for supporting the float member and the mounting portion of the valve member are formed on the same molding member. 10. The ink jet recording apparatus according to claim 9 , wherein a cylindrical ink adhesion preventing rib is formed on the molding member to which the valve member is attached so as to surround the valve member.

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